Note: Descriptions are shown in the official language in which they were submitted.
BAc~GRouND O~ THE IN~I~NTION
Field of the Invention
. . _ .
This invention relates generally to a magnetic
recording and/or reproducing apparatus, such as, a video
tape recorder (VTR), and, more particularly, is directed
to an improved apparatus for effecting automatic loading
and/or unloading of the tape in a VTR.
Existing video tape recording and reproducing
apparatus generally comprises a tape guide drum having a
rotary magnetic head assembly associated therewith to
record or reproduce video signals on or from a magnetic
tape which is usually wound on supply and take-up reels
contained in a cassette. In preparing such a video tape
recording and reproducing apparatus for operation, the
tape extending between the supply and take-up reels must
be withdrawn from the cassette and wrapped about at least
a portion of the circumference of the tape guide drum for
guiding thereby with respect to the rotary magnetic head
assembly, and the withdrawn tape has to be positioned
between a rotated capstan and a pinch roller so that the
tape can be longitudinally driven by cooperation of the
capstan and pinch roller and by suitable rotation of the
take-up reel.
One existing type of automatic tape loading
and unloading apparatus is disclosed in U.S. Patent No.
3,821,805, having a common assignee herewith, but it is
~:lt;4089
inherent in such apparatus that the same cannot be embodied
in a compact VTR.
A proposed arrangement of an automatic tape
loading and/or unloading apparatus suitable for a compact
C~n~
VTR is disclosed in~ Patent Application Serial No.
~S2,76~ 27
15/"J~I, filed May ~, 1980, and also having a common
assignee herewith. In such tape loading and/or unloading
apparatus, there are provided a feed or supply side tape
guide for wrapping tape withdrawn from an operatively
positioned cassette helically about the peripheral surface
of the tape guide drum, and a take-up side tape guide
which is moved in a direction opposite to that of the
feed or supply side tape guide with the tape guide drum
therebetween. Although the foregoing arrangement makes it
possible to provide an automatic tape loading and/or
unloading apparatus which can be incorporated in a
relatively compact VTR, there are a number of disadvantages,
in that the structures for establishing the path of movement
of the feed or su?ply side tape guide and for driving
the same are undesirably compiicated, and further in that
the configuration of the path of movement of the feed
side tape guide is restricted by various factors so that
the optimum path for obtaining smooth movement of the
tape guide and smooth guiding of the tape at the completion
of loading is not attainable.
OB~ECTS AND SUMMARY OF THE INVENTION
Accordingly, it is an object of this invention
to provide an automatic tape loading and unloading apparatus
for a VTR which avoids the above described problems
_3_
~64VH9
associated with existing apparatus of that type.
More particularly, it is an object of this
invention to provide an automatic tape loading and
unloading apparatus which can be incorporated in an
extremely compact VTR.
Another object of the invention is to provide
an automatic tape loading and unloading apparatus, as
aforesaid, which is relatively simple in construction,
and which performs the tape loading and unloading opera-
tions in a smooth manner while avoiding uneven or
concentrated stressing of the tape.
Still another object of the invention is to
provide an automatic tape loading and unloading apparatus,
as a~oresaid,and which, at the completion of a tape
loading operation, guides the tape by means of securely
located and stabilized guide elements so as to avoid
vibration of the tape during recording and reproducing
operations of the associated VTR.
In accordance with an aspect of this invention,in
a cassette-type tape recording and/or reproducing apparatus
or VTR having a tape guide drum with at least one rotary
transducer or head moved in a circular path substantially
coinciding with the circumference of the guide drum,
and a holder spaced from the guide drum for receiving a
cassette and locating the latter in an operative position
at which a plane passing through the tape in the cassette
is inclined in respect to a plane of rota~ion of the
rotary transducer; an automatic tape loading and unloading
apparatus is provided with tape engaging means,such as,
~ ~64~9
a substantially erect tape guiding element mounted on a
movable base, for withdrawing tape from a cassette in
the operative position and wrapping the withdrawn tape
about at least a portion of the circumference of the
guide drum, means, such as, a track member along which
the movable base of the tape engaging means is slidable,
for guiding the tape engaging means in a path extending
from a first position adjacent a cassette in the operative
position to a second position spaced substantially from
said first position and at which the engaged tape is
wrapped about said circumference of the guide drum,
with at least a portion of such path leading to said
second position being inclined relative to the plane of
rotation of the rotary transducer so that the tape
wrapped on the circumference of the guide drum is
arranged substantially helically in respect to the guide
drum, driving means, such as, a rotatable drive ring, for
effecting movements of the tape engaging means between
its first and second positions, such driving means being
movable in a plane substantially parallel to the plane
passing through the tape in the operatively positioned
cassette, and connecting means extending between the
driving means and the tape engaging means, for example,
in the form of a connecting rod assembly pivotally
connected at its opposite ends to the drive ring and to
the movable base of the tape engaging means, and through
which said driving means moving in said plane of movement
thereof can effect movements of said tape engaging means
in said path between said first and second positions.
~164QH9
Further, in a preferred embodiment of the
invention, additional tape guiding elements are mounted
at spaced apart locations on the driving means for
movement with the latter between initial and operative
positions corresponding to the disposition of the tape
engaging means in the first and second positions,
respectively, thereof, with each of the tape guiding
elements being individually movable relative to the
driving means between a supine condition and a substan-
tially erect condition, and with guide means being
operable on the tape guiding elements for disposing each
of the latter in its supine condition at the respective
initial position, and for moving each tape guiding element
to its erect condition in moving with the driving means
to the operative position of the respective tape guiding
element.
In accordance with another aspect of this
invention, the automatic tape loading and unloading
apparatus further includes second tape engaging means
for withdrawing tape from the operatively positioned
cassette and leading the withdrawn tape adjacent a rotated
capstan of the VTR, and means for guiding the second
tape engaging means in a path lying in a plane parallel
with the plane of movement of the driving means and
extending from a first position adjacent the operatively
positioned cassette to a second position at which the
engaged tape is led adjacent the capstan, with the
driving means being operative for effecting movements of
the second tape engaging means between its first and
J.164~8g
second positions simultaneously with the movements of the
first mentioned tape engaging means between the first and
second positions of the latter.
The above, and other ob3ects, features and
advantages of the invention, will be apparent in the
following detailed description of an illustrative
embodiment thereof which is to be read in connection
with the accompanying drawings.
~64Q89
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic plan view illustrating
the guided path of a magnetic tape in a VTR having a
tape loading apparatus according to an embodiment of this
invention, and showing the tape in its loaded state;
Fig. 2 is a schematic side elevational view
of the VTR at the tape feeding side thereof;
Fig 3 is a schematic side elevational view of
the VTR at the tape take-up side thereof;
Fig. 4 is a schematic rear elevational view of
the VTR with the tape in its loaded state;
Fig. 5 is a top plan view, which is partly
cut away and in section, of the VTR having a tape loading
apparatus according to an embodiment of the invention,
and which shows the relative dispositions of the major
components of such tape loading apparatus with the tape
in its loaded state;
Fig. 6 is a perspective view of a guide assembly
included in a feed side loading unit of the tape loading
apparatus according to this invention;
Fig. 7 is a plan view of the guide assembly of
Fig. 6;
Fig. 8 is a plan view of a drive ring
included in the feed side loading unit and which is disposed
below the guide assembly of Fig. 7;
Fig. 9 is an elevational view, partly in section,
and developed in a flat plane for showing the feed side
loading unit of the tape loading apparatus upon the
completion of a tape loading operation;
Fig. 10 is a developed view similar to that of
Fig. 9, but showing the feed side loading unit upon the
completion of a tape unloading operation;
Fig. 11 is an exploded perspective view of the
elements making up a movable base portion of the feed
side loading unit;
Fig. 12 is a perspective view of the assembled
movable base portion which is shown disposed near to its
operative position;
Fig. 13 is a plan view of the movable base
portion in its operative position;
Fig. 14 is a sectional view taken along the line
XIV-XIV on Fig. 13;
Fig. 15 is an enlarged sectional view taken along
the line XV-XV on Fig. 13;
Fig. 16 is a plan view of a connecting rod
assembly included in the feed side loading unit for
connecting the movable base portion of Figs. 11-15 with
the drive ring of Fig. 8;
Fig. 17 is a sectional view taken along the line
XVII-XVII on Fig. 16;
Fig. 18 is a perspective view of one of a
plurality of collapsible tape guiding elements included
in the feed side loading unit, and which is shown in an
erect position;
Fig. 19 is a plan view of the tape guiding
element of Fig. 18, but shown in a collapsed or supine
position;
_g_
4~89
Fig. 20 is a sectional view taken along the
line XX-XX on Fig. 19, and showing the tape guiding
element in various positions thereof;
Fig. 21 is a partially cut away perspective
view showing a control guide by which movements of the
collapsible tape guiding elements of the feed side
loading unit are controlled, particularly in the region
of a tape cassette;
Fig. 22 is an enlarged, fragmentary plan view,
which is partially cut away for showing details of the
control guide of Fig. 21;
Fig. 23 is a fragmentary sectional view taken
along the line XXIII-XXIII on Fig. 22;
Fig. 24 is a fragmentary sectional view taken
along the line XXIV-XXIV on Fig. 22;
Fig. 25 is a perspective view of a positioning
plate assembly by which the collapsible tape guiding
elements of the feed side loading unit are securely
maintained in their operative positions;
Fig. 26 is an elevational view, partly in
section, and developed on a flat plane of the tape guiding
elements of the feed side loading unit when moving to,
and at their respective operative positions;
Fig. 27 is a plan view of a detecting device for
detecting the end or completion of a tape loading
operation of the apparatus according to this invention;
Fig. 28 is a plan view of a detecting device for
detecting the end or completion of an unloading operation
of the apparatus;
-10-
;4~89
Fig. 29 is a perspective view of a movable base
assembly included in a take-up side loading unit of the
tape loading apparatus according to an embodiment of this
invention;
Fig. 30 is a plan view of the movable base
assembly of the take-up side loading unit;
Fig. 31 is a sectional view taken along the
line XXXI-XXXI on Fig. 30;
Fig. 32 is a fragmentary enlarged plan view of
a locking mechanism which cooperates with the movable
base assembly of the take-up side loading unit in the
operative position of such assembly;
Fig. 33 is a sectional view taken along the
line XXXIII~XXXIII on Fig. 32;
Fig. 34 is a plan view of a pinch roller
pressing unit which cooperates with a pinch roller of the
take-up side loading unit;
Fig. 35 is a perspective view of the pinch
roller pressing unit;
Figs. 36, 37 and 38 are plan views, partly
cut away and in section, and showing parts of the pinch
roller pressing unit of Fig. 34 in different phases of
its operating cycle;
Fig. 39 is a partially cut away perspective
view of a driving unit included in the tape loading
apparatus according to this invention;
~i6~
Fig. 40 is a plan view showing principal elements
of the driving unit;
Fig. 41 is a plan view of a head shielding
tape guiding assembly on which the tape is slidable upon
opening of a cassette lid during movement of the cassette
to its operative position;
Fig. 42 is a front elevational view of the
tape guiding assembly shown on Fig. 41;
Figs. 43 and 44 are side elevational views of
the tape guiding assembly of Figs. 41 and 42 and
illustrating the operation thereof in cooperation with
a cassette shown in section during the movement of such
cassette to its operative or loaded position;
Fig. 45 is a perspective view of a tension
detecting unit included in the VTR havinga tape loading
apparatus according to this invention;
Figs. 46 and 47 are plan views of the tension
detecting unit when the tape loading apparatus according
to this invention is in other than its fully tape loaded
condition, and in such fully tape loaded condition,
respectively;
Fig. 48 is a perspective view of a cassette
holder locking unit included in the VTR having a tape
loading apparatus according to this invention;
Figs. 4~ and 50 are partially cut away side
elevational views showing a portion of the cassette
holder locking unit conditioned for locking the cassette
-12-
~64~89
holder in its lowered or operative position, and for
releasing the cassette holder, respectively;
Fig. 51 is a plan view of a tape pressing unit
mounted on a guide drum of the VTR having a tape loading
apparatus according to this invention;
Fig. 52 is a front view of the tape pressing
unit of Fig. 51, and showing how the same maintains the
tape in contact with a guiding ledge on the drum;
Fig. 53 is a sectional ~iew taken along the
line LIII-LIII on Fig. 52;
Fig. 54 is a plan view showing an additional
arrangement for controlling the angular position of one
of the collapsible tape guiding elements as the latter
is moved toward its operative position;
Fig. 55 is a sectional view taken along the
line LV-LV on Fig. 54; and
Fig. 56 is a sectional view taken along the
line LVI-LVI on Fig. 54.
DESCRIPTION OF A PREFERRED EMBODIMEN_
A tape loading apparatus according to one
embodiment of the present invention, as incorporated in
a magnetic recording and/or reproducing apparatus,
particularly, a helical type VTR, will initially be
described in a brief or outline manner with reference to
Figs. 1-4. Such VTR employs interchangeable tape cassettes,
one of which is indicated at 1 and shown to include
supply and take-up reels 2 and 3 rotatably arranged side-
by-side within the cassette 1. A magnetic tape 4 is
~64Q`8~
wound on reels 2 and 3 and extends therebetween about
suitable guides lb and lc in the cassette so that a run
4' of the tape 4 will extend along one side la of the
generally rectangular cassette 1 when the latter is not
in use. The VTR includes the usual cassette loading
mechanism (not shown) which is movable to receive the
cassette 1 in an elevated position and then dispose the
cassette in an operative horizontal position close to
a horizontal chassis 5 of the VTR. In such operative
horizontal position of cassette 1, the reels 2 and 3 are
engaged with a feed reel mount 6 and a take-up reel mount
7 disposed on chassis 5. During movement of cassette 1
to its inoperative position on chassis 5, a lid 9 of
cassette 1 is opened upwardly to uncover a front opening
8 of the cassette extending along the side la thereof,
and hence to expose the run 4' of the tape. Further, the
cassette 1 is shown to have a cut out 10 formed in its
underside ld and communicating with the front opening 8.
The VTR of Figs. 1-4 is further shown to include
a rotary head drum 13 disposed in an inclined manner on
chassis ; in front of the operatively positioned cassette 1
and having one or more rotary magnetic heads (not shown
on Figs. 1-4) by which video signals can be recorded on
and/or reproduced from the magnetic tape 4 when the
latter is wrapped helically about at least a portion of
the periphery of drum 13. The tape loading apparatus
according to this invention generally comprises a feed side
-14-
loading unit or mechanism 14 engageable with the tape
run 4' in the operatively positioned cassette 1 and
operative, in a loading operation, for drawing the tape
from cassette 1 generally near the side of the latter
housing the supply reel 2, and a take-up side loading
unit or mechanism 15 also engageable with the tape run
4' and being operative, during a loading operation, to
withdraw the tape from the portion of cassette l housing
take-up reel 3. The feed side loading unit 14 generally
includes four movable tape guiding elements 16, 17, 18
and 19 which occupy the positions shown in ~ull lines
on Fig. 1 at the completion of a tape loading operation,
and are movable thereto from their respective initial
or inoperative positions indicated in broken lines at
16', 17', 18' and 19', respectively. The take-up side
loading unit 15 is shown to include one movable tape
guiding element 20 which, at the completion ofa tape
loading operation, occupies the position shown in full
lines on Fig. 1, and also a pinch roller 21 which is in
following relation to the tape guiding element 20 during
movement of the tape guiding element 20 and pinch roller
21 to their positionsshown in full lines on Fig. 1 from
their initial or inoperative positions indicated in broken
lines at 20' and 21', respectively. The tape guiding
elements 16 and 17 of feed side loading unit 14, and the
tape guiding element 20 and pinch roller 21 of take-up
side loading unit 15 are substantially erect in their
-15-
~1~i4~89
inoperative or initial positions indicated at 16', 17',
20' and 21', respectively, as well as in the positions
occupied thereby at the completion of a loading operation.
However, the tape guiding elements 18 and 19 of feed
side loading unit 14 are collapsible so as to occupy
substantially supine initial positions, as at 18' and
19', and to be erected or raised for guiding action on
the tape 4 in the course oftheloading operatio~ as here-
inafter described in detail.
Suitably mounted above chassis 5 are a capstan
23 located to be adjacent pinch roller 21 in the operative
position of the latter, a fixed tape guide 24a located
to lead a run 4b of the tape between pinch roller 21 and
capstan 23 to movable tape guide 20 in the operative
position of the latter, and a fixed tape guide 24b located
to lead the tape from tape guide 20 back to the guide lc
in cassette 1 at the take-up side of the latter. Also
suitably mounted above chassis 5 are tape guides 25 and
26 fixedly located adjacent drum 13 for leading the tape
tangentially to and from the peripheral surface of drum 13
at points which are approximately diammetrically opposed
so that the tape will be wrapped about a little more than
a 180 angular extent of the drum, as at 4a. A full width
erase head 27 is mounted on chassis 5 so as to engage the
tape at the completion of a tape loading operation between
guiding element 16 and fixed tape guide 25 for erasing all
signals previously recorded on the tape, that is, any
video signals recorded in oblique tracks, any audio signals
-16-
~:16~Q89
recorded in one or more respective tracks extending long-
itudinally along one edge portion of the tape, and any
control or CTL signals recorded in a track extending
longitudinally along the opposite edge of the tape.
An audio erase head 28 and a combined head 29 for recording
and reproducing audio signals and for recording and
reproducing CTL signals are also suitably mounted above
chassis 5 for engagement with the tape 4 between guides
26 and 24a upon the completion of a tape loading
operation. The head 28 is selectively employed to erase
only recorded audio signals, for example, when it is
desired to edit or change the audio associated with
recorded video, and the head 29, which is disposed down-
stream relative to the erase head 28, considered in the
direction of movement of tape 4 during recording and
reproducing operations of the VTR, is employed for
recording and reproducing the audio signals and/.or for
recording and reproducing the CTL signals utilized in the
ù~ual servo mechanisms of the VTR. Further, at the
completion of a loading operation, a tension detecting
pin 30 engages the tape between guiding element 19 of
the feed side loading unit 14 and the guide lb at the
respective side of cassette 1 for detecting the tension
in the t~pe being unwound from supply reel 2 and, as
hereinafter described, for correspondingly varying the
resistance to turning of the supply reel so as to maintain
a substantially constant tension.
-17-
i.164g~89
As previously noted, upon the completion of an
unloading operation of the tape loading apparatus
according to this invention, the various movable tape
guiding elements are in the positions indicated in
broken lines at 16'-20' and the pinch roller is in the
position indicated in broken lines at 21', with tape
guiding elements 18' and 19' being supine. With the
movabl.e tape guiding elements 16'-20' and the pinch roller
21' being thus positioned, a cassette 1 is brought down
from above to its horizontal operative or loaded position,
with the result that the tape guiding elements 16', 17'
and 20' and the pinch roller 21' project upwardly
~hrough the cut out 10 at the bottom of the cassette 1
and are positioned in back, or at the inside of run 4'
of the tape in the cassette.
After the cassette 1 has been disposed in its
loaded or operative position, a tape loading operation
may be initiated to cause tape guiding elements 16-19 of
feed side loading unit 14 to move in a generally clockwise
direction about drum 13 from the previously described
initial positionsindicated at 16'-19'. In synchronism
with such movement of tape guiding elements 16-19, the
movable tape guiding element 20 and pinch roller 21 of
the take-up side loading unit 15 are moved in a generally
counterclockwise direction about drum 13 from their
initial positions indicated at 20' and 21'. In the course
of such movements, the tape 4 in cassette 1 is engaged
successively by guiding elements 16-19 at the tape feed
1~6~
side, and by guiding element 20, at the take-up side,
whereby loops of the tape 4 are drawn out from the
front opening 8 of the cassette 1 at the left-hand and
right-hand portions of such opening, as viewed on Fig. 1.
It will be appreciated that, in moving from their
initial positions indicated in broken lines at 18' and
19' on Fig. 1, the collapsible tape guiding elements
18 and 19 are maintained in their supine or collapsed
conditions, as hereinafter described in detail, so as
to move, in succession, under heads 28 and 29 and under
the tape being drawn out by movable tape guiding element
20 for entry into the operatively positioned cassette 1,
whereupon, the tape guiding elements 18 and 19 are made
to rise in succession to increasingly erect orientations
for engagement with the tape extending between guide la
in the cassette and movable guiding element 16.
As is particularly apparent on Figs. 2 and 4,
as the tape guiding elements 16 and 17 of feed side
loading unit 14 are drawn out from the front opening 8
of cassette l and move in a clockwise direction about
drum 13, such tape guiding elements 16 and 17 initially
move in a curved path lying in a horizontal plane, that
is, a plane parallel to the underside ld of cassette 1,
and then the arcuate path of tape guiding elements 16
and 17 is inclined upwardly until, at the completion of
a loading operation, the tape guiding element 16, in its
final or operative position, is substantially elevated
in respect to chassis 5 and disposes the tape engaged
thereby near to the upper portion of drum 13, as shown
particularly on Fig. 4. lhus, the tape 4 being drawn
out of cassette 1 past guide lb in the latter, is initially
withdrawn substantially horizontally fromthe front opening
8 and is then wound or wrapped gradually against the
peripheral surface of drum 13 while being lifted or
raised gradually in the axial direction of the drum, that
is, from the lower portion to the upper portion of the
latter. On the other hand, and as clearly shown on
Figs. 3 and 4, the tape guiding element 20 of take-up
side loading unit 15 moves in an arcuate path lying in a
horizontal plane so that, at the take-up side of cassette
1, the tape 4 is withdrawn from the front opening 8 in
the horizontal direction.
When the tape guiding elements16-20 and pinch
roller 21 have attained their respective operative
positions indicated in full lines on Fig. 1, the loading
of the tape 4 on drum 13 is completed. At the completion
of the tape loading operation, the tape 4 extending from
supply reel 2 of ca~sette 1 passes fullwidth erase head 27
and then is wrapped helically, as indicated at 4a, on the
peripheral surface of drum 13 for an angular extent of
180 + ~, and the tape extending from drum 13 runs
horizontally past audio erase head 28, combined CTL and
audio recording and reproducing head 29 and capstan 23
before being guided back to take-up reel 3. Further, in
the course of the loading operation, the tension detecting
pin 30 is moved from its inoperative or initial position,
indicated in broken lines at 30', to its operative position
-20-
~64~B9
shown in full lines on Fig. l. After completion of the
loading operation, a recording or reproducing mode of the
VTR may be established, for example, in response to
actuation of a corresponding push-button (not shown), so
as to bring pinch roller 21 into pressure contact with
capstan 23, as shown in broken lines on Fig. 1, whereby
the tape is driven between rotated capstan 23 and pinch
roller 21, Thus, the driven tape is unwound from supply
or feed reel 2 and passes full width erase head 27 prior
to moving about the periphery of drum 13 and then passing
heads 28 and 29 before being rewound on take-up reel 3.
In the recording mode of the VTR, head 27 is made operative
to erase any signals previously recorded on the tape,
whereupon the rotary head or heads associated with drum
13 record video signals in oblique tracks on the tape
and head 29 records associated audio signals and CTL
signals in the respective longitudinal tracks. In the
reproducing mode of the VTR, the full width erase head 27
is made inoperative and the rotary head or heads associated
with drum 13 reproduce the video signals, while head 29
reproduces the associated audio and CTL signals. Upon
the completion of a recording or reproducing operation of
the VTR, an eject push-button (not shown) may be
actuated to cause the return of tape guidin~, elements
16-20 and pinch roller 21 to their respective initial
positions, whereby the tape 4 is unloaded from drum
13 and returned to cassette 1 to permit ejection of
89
the latter.
In addition to the loading units 14 and 15 which
effect the previously described movements of the respective
tape guiding elements, the tape loading apparatus according
to this invention preferably also comprises the following
components which will now be described with reference to
Fig. 5. More particularly, a rising motion guide 33 is
shown to be located on chassis 5 so as to extend upwardly
into the cutout 10 in the bottom of the operatively
positioned cassette 1, and such guide 33 is adapted to
control the rising or upward swinging movements of the
tape guiding elements 18 and 19 as the latter move under
the front portion of cassette 1 and into contact with
the tape 4 being withdrawn from the latter. As the tape
guiding elements 18 and 19 near their respective opera-
tive positions, such elements 18 and 19 are respectively
engaged by positioned plates 34 and 35 which positively
establish the orientations of the operatively positioned
guiding elements 18 and 19. At one side of drum 13, a
driving unit 36 is mounted on cassette 5 for driving
both loading units 14 and 15. Adjacent driving unit 36
there is disposed a pinch roller pressing unit
37 which is operative in the recording or reproducing
mode of the VTR to press pinch roller 21 against
rotated capstan 23 with the tape 4 therebetween
for driving the tape. ~lead shielding tape guides 38 and
39 are mounted above heads 28 and 29 and the fixed tape
guide 26 and are slidably engageable by the tape in
i~6~
cassette 1 to prevent hang up of the tape thereon during
loading of the cassette, as hereinafter described in
detail. A tension detector 40 is associated with the
tension detecting pin 30, and a cassette holder locking
unit 41 is provided to prevent removal of a cassette
from its operative position other than upon completion
of a tape loading operation.
Referring now to Figs. 6 and 7, it will be seen
that the feed side loading unit 14 comprises a guide
track member 44 which may be molded from a synthetic
resin and is mounted on chassis 5. Guide track member
44 is generally of inverted U-shaped cross section so as
to have arcuate outer and inner side walls 44a and 44b
(Figs. 6 and 21) between which there extends a curving
top wall 45 having a similarly curving slot 46 extending
therealong. The curved guide track member 44 extends in
a clockwise direction, as viewed from above, about drum
13 from a position below the cut out 10 in the underside
of an operatively positioned cassette. As is particularly
evident in the developed view of Fig. 9, an initial end
portion 45a of the top wall 45 of track member 44, that
is, the end portion thereof which extends from under an
operatively positioned cassette, is horizontal and in
relatively close proximity to the chassis 5. The
remaining portion 45_ of top wall 45 extendind from
approximately the operative position of tape guiding
element 19 is inclined gently upward to the end of track
member 44 which is remote from the operatively positioned
il64~89
cassette 1. Adjacent to the end of track member 44 which
is remote from the operatively positioned cassette 1, a
metal guide plate 47 is rigidly supported on posts 48
extending from chassis 5 so as to dispose plate 47 in
flush and similarly inclined relation to the adjacent
end portion 45b of wall 45. The guide plate 47 is formed
with a guide slot 49 opening at one end of plate 47 in
registry with the slot 46 of guide track member 44.
A circular drive ring 51 (Fig. 8) which is
eccentric in respect to drum 13 is rotatable on chassis
between the outer and inner side walls 44a and 44b of
guide track member 44 (Fig. 21). Ring 51 is supported
for such rotation in a horizontal plane, for example, by
means of three equally spaced apart flanged guide rollers
52 (Fig. 8) rotatably mounted on chassis 5. A substantial
portion of the outer periphery of ring 51 is formed with
teeth to define a peripheral gear 53 through which ring
51 may be turned, as hereinafter described in detail, for
providing a tape loading or unloading operation of the
apparatus. As shown particularly on Figs. 7 and 10, for
the purpose of maintaining tape guiding elements 1~ and
19 substantially supine when in their inoperative positions
and when moving toward and away fromsuch positions, a relatively
thin guide depressing plate 54, for example, of stainless
steel, which is laterally curved, extends.substantially
horizontally in relatively close proximity to chassis 5
above ring 51 from approximately the loca~ion of guide
plate 47 to approximately the end of guide track member 44
-24-
~64~89
extending under cassette 1.
Referring now to Figs. 11-15, it will be seen
that the movable tape guiding elements 16 and 17 are
mounted on a movable base portion 56 which is adapted
to be moved along the upper wall surface 45 of track
member 44 while being guided by slot 46 thereof. The
movable base portion 56 is shown to include an upper
block 59 adapted to slide on the upper surface of wall
45 and plate 47 and being formed with a depending, integral
projection 58 which is laterally curves so as to be
received in, and movable along slots 46 and 49. Movable
base portion 56 further includes a lower block 61 adapted
to be disposed at the under side of wall 45 and secured
to projection 58 by means of set screws 60. A relatively
thick guide supporting metal plate 62 has one end portion
secured between projection 58 and lower block 61 by means
of the set screws 60. The other or free end portion of
plate 62 projects longitudinally beyond blocks 59 and 61
so as to be cantilevered and somewhat resilient, and a
supporting shaft 63 is suitably secured at its lower end
in such free end portion of plate 62 and projects upwardly
therefrom. A helical compression spring 64 extends around
the lower end portion of shaft 63 below a cupped hub
65a of a lower flange member 65. A sleeve 66 is slidable
on shaft 63 above flange member 65, and an upper flange
member 67 has a hub 67a formed with a threaded bore 68 which
is screwed on a threaded upper end portion 69 of shaft 63
so that hub 67a axially abuts the adjacent end of sleeve 6fi.
-
-25-
~164`~89
Upper flange member 67 further has a central, reduced
diameter bore 70 which is threaded and opens into threaded
bore 68 to receive a locking screw 71 adapted to press
axially against the upper end of shaft 63. The tape
guiding element 16 is shown to be constituted by a roller
72 which is rotatable on sleeve 66 between the upper
and lower flange members 67 and 65. Preferably, and
as shown particularly on Fig. 14, roller 72 includes a
relatively thick cylindrical central portion 73 having
an axial length slightly smaller than that of sleeve 66
and closely engaging the latter with upper and lower
shoulders of cylindrical portions 73 being adapted to
oppose or confront the cup-shaped hub 65a of lower
flange member 65 and the hub 67a of upper flange member
67 for axially locating roller 72. Further, a slot or
groove 74 is formed diametlically in the upper surface
of upper flange member 67 for receiving a screw driver
or similar tool by which upper flange member 67 may be
rotated relative to shaft 63.
It will be appreciated that the above described
construction for constituting tape guiding element 16
and mounting the latter on movable base portion 56 forms
a height adjusting unit 75 for element 16. More particu-
larly, turning of upper flange member 67 relative to
shaft 63 will, by reason of threads 69, cause vertical
movement of flange member 67. Since spring 64 continuously
urges lower flange member 65 and sleeve 66 upwardly
-26-
~i64~89
against upper flange member 67, the described vertical
movement of the latter will cause adjustments of the
height of tape guiding element 16 in the direction of
arrow A on Fig. 14. After such adjustment has been
effected, lock screw 71 may be tightened against the
upper end of shaft 63 for securing upper flange member
67 in its adjusted position.
A threaded hole 77 is formed centrally in an
end portion of upper block 59 which overlies the canti-
levered or free end portion of guide supporting plate
62, and an adjusting screw 78 is threadably inserted in
such hole 77 from above to engage, at its lower end,
with the upper surface of plate 62. Preferably, the
lower surface of the projection 58 of upper block 59
has a bevel or inclination 79 at the end thereof from
which plate 62 extends, and the corresponding end portion
of lower block 61 has a notch 80 to which an inclined
end surface 81 extends so that the inclined end surfaces
79 and 81 and the notch 80 will permit flexing of the
free end portion of plate 62, as indicated by the broken
lines on Fig. 14.
It will be understood that the mounting of tape
guiding element 16 on movable base portion 56 by way of
cantilevered plate 62 and the screw 78 acting against
such plate 62 provides a tilt adjusting unit 82. More
particularly, by adjusting screw 78, the free end portion
of guide supporting plate 62 is flexed or deflected in
the vertical direction within the space provided between
~64Q89
inclined surfaces 79 and 81, with the result that shaft
63 of guiding ele~ent 16 is angularly deflected or tilted
in the direction of the arrow B on Fig. 14.
The tape guiding element 17 is shown to be
constituted by a guide pin which is fixed in respect to
an extension 59a of upper block 59 at the end of the
latter remote from guiding element 16. The guide pin
constituting element 17 is seen to be inclined at a
predetermined angle so as to slightly converge upwardly
in respect to the axis of element 16.
As shown particularly on Fig. 11, the lower
block 61 has protuberances 84a and 84_ formed integrally
with its upper surface adjacent the opposite ends of
its outer side portion, considered in respect to the
curvature of track member 44, and a similar protuberance
84c extends from the upper surface of block 61 in
lateral alignment with protuberance 84a, but adjacent
the inner side of block 61. Thus, when movable base
portion 56 is moved on to guide plate 47, protuberances
84a and 84_ and protuberance 84c are adapted to engage
the underside of plate 47 at opposite sides of slot 49,
particularly if base portion 56 is then urged upwardly
relative to plate 47. Further, as shown particularly on
Figs. 14 and 15, the end portions of lower block 61 at
opposite sides of notch 80 therein are inclined to form
a pair of upwardly slanting faces 85, and a lock pin 86
is mounted below guide plate 47 so as to extend transversely
in respect to slot 49.
-28-
Q~39
The protuberances 84a - 84c, inclined faces 85
~qnd pin 86 combine to provide a locking or securing
mechanism 87 by which tape guiding elements16 and 17 are
securely positioned when moved to their respective
operative positions.
More particularly, when movable base portion 56
is moved along slot 49 in the direction of arrow C on
Fig. 13 and approaches its operative position there
illustrated, both inclined faces 85 of lower block 61
move onto pin 86, as is shown on Fig. 15. Thus, during
the final increment of movement of movable base portion
56 to its operative position, the engagement of inclined
faces 85 with pin 86 provides a wedge effect by which the
final movement of lower block 61, as indicated by the
arrow D on Fig. 15, has an upwardly directed component
by which the three protuberances 84a - 84c are pressed
against, or urged into biting contact with the lower
surface of guide plate 47 at the opposite sides of slot
49. Consequently, in the operative position of movable
base portion 56, the latter is rigidly secured to the
fixed guide plate 47 for stable positioning of tape guiding
elements 16 and 17.
Referring now to Figs. 16 and 17, it will be
seen that movable base portion 56 is connected to drive
ring 51 by a connecting rod assembly 89 which is inclined
therebetween. Connecting rod assembly 89 is shown to
include a rod 90 and cylinder 91 which may be both molded
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i~64~g
from a suitable synthetic resin, with the cylinder 91
having an axial bore 92 open at one end for slidably
receiving an end portion of rod 90. A pair of triangular
projections 93 are formed on such end portion of rod 90
at diametrically opposed locations so as to be slidable
in respective diametrically opposed slots 94 extending
axially in cylinder 91. Diametrically opposed slits 95
are also formed axially in cylinder 91 extending from the
end of the latter at which bore 92 opens, and such slits
95 are angularly displaced by 90 from the slots 94.
The projections 93 on rod 90 are in the form of right
triangles so as to define slanting faces directed toward
the free end of rod 90 and faces at right angles to the
axis of rod 90 which are directed away from the free end
of the latter. By reason of such configuration of
projections 93 and the slits 95 in cylinder 91, rod 90
can be forced axially into cylinder 91 with the open end
portion of cylinder 91 being elastically expanded by
projections 93 until the latter snap into slots 94. There-
after, the faces of projections 93 extending at right
angles to the axis of rod 90 will prevent the axially
separation of the latter from cylinder 91. At the end of
rod 90 remote from the end portion thereof slidable in
cylinder 91, rod 90 is provided with an integral flange
96, and a helical compression spring 97 is provided on
rod 90 between flange 96 and the open end surface of
cylinder 91 for yieldably urging rod 90 to its extended
position relati~e to cylinder 91 in which projections 93
-30-
89
engage ends of slots 94 for preventing removal of rod 90
from cylinder 91, as shown on Fig. 17.
Extending from the end of rod 90 having flange
96 thereon is a terminal portion having lugs 98 extending
laterally from its opposite sides, with each lug 98
having the cross sectional configuration of a circle
with diametrically opposed flattened faces e~tending
parallel to the axis of rod 90. Such projections 98 are
rotatable in circular seats 100 formed in a bracket 99
secured on ring 51. The circular seats 100 open upwardly
through narrowed passages lOOa of a width tl greater
than the width of each projection 98 between the flat
faces of the latter. Thus, if rod 90 is initially
disposed in a vertical position, as indicated in broken
lines at 90' on Fig. 17, projections 98 can pass through
passages lOOa for installation in circular seats 100.
Thereafter, when rod 90 is inclined, projections 98 are
rotatably retained in seats 100.
The end of cylinder 91 remote from the opening
of its bore 92 has a ball 101 formed integrally therewith
to be received in a socket 102 provided at the end of
lower block 61 of movable base portion 56 remote from
notch or cut out 80. Thus, a ball-and-socket joint 103
is provided for connecting rod assembly 89 .o movable
base portion 56. Preferably, as shown particularly on
Fig. ll, the end of lower body or block 61 provided with
socket 102 may be longitudinally split, ~hat is, formed
with a lateral portion 104 which is detachably secured to
~164~89
the remainder of lower block 61 by a screw 105 Thus,
screw 105 can be loosened to permit the insertion or
removal of ball 101 in socket 102.
Referring now to Figs. 18-20, it will be seen
that the collapsible tape guiding elements 18 and 19 are
similar and each include an elongated guide pin 106 which
is pivotally mounted, at one end, in a mounting bracket
107 suitably secured on drive ring 51. More particularly,
and as is shown for the tape guiding element 18, the
elongated guide pin 106 is formed integrally, at one end,
with a laterally directed pivot pin 108 which is rotatable
in ears 107a on one end of mounting bracket 107. The
axis of pivot pin 108 extends generally across the width
of drive ring 51 so that guide pin 106 is swingable
between a substantially horizontal or supine inoperative
position (Fig. 19) in which pin 106 extends generally
along the upper surface of ring 51, and a substantially
erect position (Fig. 18), The pivoted end portion of pin
106 further has an anchor pin 109 projecting from one
side thereof at a distance from pivot pin 108, and a
helical tension spring 111 extends between anchor pin 109
and a lug 110 on ring 51 for continuously urging guide
pin 106 in the clockwise direction, as viewed on Fig. 20,
that is, to its erect position. Further, a lug 114 acting
as a stop is formed on guide pin 106 adjacent the pivoted
end portion thereof and is engageable with the upper
surface of a positîoning leaf spring 112 for limiting
the pivoting movement of guide pin 106 under the urging
-32-
~6~
of spring 111. As shown particularly on Fig. 20, one end
portion of leaf spring 112 is secured by a screw 113 on
~mounting bracket 107, and the remainder of leaf spring
112 extends over a recess 107b of the mounting bracket
so that the end 112a of spring 112 engageable by lug 114
can flex downwardly under the urging of guide pin 106.
Further, an adjusting screw 115 extends through leaf
spring 112 and is screwed into a tapped hole in bracket
107 for adjusting the position of the free end 112a of
spring 112 at which lug 114 first comes into contact
therewith during pivoting of guide pin 106 in the direction
toward its erect position.
In other words, screw 115 acting on spring 112
makes it possible to adjust the inclination of the guide
pin 104 in its raised position shown with full lines on
Fig. 20.
So long as collapsible tape guiding elements
18 and 19 are in their respective initial or original
positions indicated at 18' and 19' on Fig. 1, such guiding
elements are disposed under depressing plate 54 (Figs. 6
and 7) and are thereby held down so as to be nearly
horizontally disposed against the force of the related
springsll, as shown on Fig. 10. At the commencement of
the loading operation, in which ring 51 is turned in the
clockwise direction as viewed on Fig. 8, the corresponding
movements of guiding elements 18 and 19 cause the latter
to move successively out from under depressing plate 54
at the end 54a of the latter ~Fig. 7).
:~6~89
The swinging movements of guiding elements 18
and 19 under the urging of the respective sprin~s 111
after moving out from under the end 54a of depressing
plate 54 are controlled by rising motion guide 33. As
shown particularly on Figs. 21 and 22, guide 33 is
desirably molded of a synthetic resin or the like so as
to have a substantially triangular planform with
depending skirts or walls 33a and 33b depending from
the sides of guide 33, at the relatively wide end portion
of the latter (Fig. 23), for defining a passage 117 there-
between through which guiding elements 18 and 19 can
move in succession. The underside of guide 33 which
forms the ceiling of passage 117 is formed with an
arcuate guide groove 118 therein (Figs. 21-24) for
guiding the free or tip ends 18a and l9a of guiding
elements 18 and 19, respectively, during movements of
the latter through passage 117. A cushioning member or
pad 119, for example, of an elastomeric synthetic resin,
is secured, as by adhesive, in the end portion of guide
groove 118 which is adjacent the relatively wide end
of rising guide 33.
When a cassette 1 is moved, from above, to its
operative position above chassis 5, guide 33 enters the
cassette, from below through cut out 10 of the cassette,
and is disposed at the inside of tape 4, as shown on
Figs. 22 and 23. When ring 51 is turned in the clockwise
direction, as viewed on Fig. 8, for initiating a tape
loading operation, the collapsible tape guiding elements
-34-
#9
:L8 and 19 move from their respective original positions
:indicated at 18' and 19' on Fig 1 and move in succession
:in the direction of the arrow E on Fig. 22 so as to
successively pass under tape 4 and enter the cassette 1
through cut out 10 thereof. Un~il the tip ends 18a and
l9a of guiding elements 18 and 19 have passed under tape
4, the elements 18 and 19 are maintained in their
respective supine positions by depressing plate 54, as
shown on Fig. 10. However, as the tip end 18a or l9a of
the guiding element 18 or 19, respectively, passes
under tape 4, the guiding element 18 or 19 moves out
from under depressing plate 54 at the end 54a of the
latter, whereupon, the respective guiding element 18 or
19 i8 free to be swung upwardly within cassette 1 at
the inside of tape 4 by the force of the respective
spring 111. In the course of this initial upward swinging
movement of guiding element 18 or 19, the respective
tip end 18a or l9a initially strikes the lower surface
of the cushion or pad 119 which absorbs the shock, and
then the tip end 18a or l9a moves into guide groove 118.
Until the tip ends 18a and l9a of guiding elements 18
and 19 move successively out of guide groove 118, the
height and moving locus of such tip end 18a or l9a is
positively controlled by guide 33. As each of the tip
ends 18a and l9a moves out of guide groove 118, the
respective guiding element 18 or 19 is free to be raised
by the respective spring 111 to the risen or erected
position, for example, as indicated at 18 on Fig. 20,
in which the lug or stop 114 comes into engagement with
-35-
~64~
adjusted leaf spring 112. In such risen or erected position,
the guiding elements 18 and l9 successively come into
engagement with tape 4 at the inside of the loop being
formed in the tape during the withdrawal of the latter
from the cassette by guiding elements 16 and 17. It will
be seen that the position where the tip ends 18a and l9a
of guiding elements 1~ and 19 successively exit from
guide groove 118, and thus are free to rise, is located
adjacent the front opening 8 of the operatively positioned
cassette 1, so that the tip ends 18a and l9a can safely
pass under the end edge 9a of the opened cassette lid 9
(Figs. 21 and 23) and avoid the possibility of accidentally
engaging such edge 9a with the guiding elements 18 and
19 at the time when the latter are being erected or swung
upwardly.
Referring now to Figs. 25 and 26, it will be
seen that the positioning plates 34 and 35 for guiding
elements 18 and 19, respectively, are horizontally fixed
to the upper end portion of a mounting block 121 by means
of screws 122 and 123. The mounting block 121 is suitably
secured on chassis 5, and positioning plates 34 and 35 are
angularly fixed relative to each other and relative to
mounting bl~ck or support 121 by means of positioning pins
124 and 125, which may be molded integrally with
mounting block 121,and which are received in holes 126
and 127, respectively, formed in positioning plates 34
and 35. The positioning plates 34 and 35 have end portions
extending over the path of travel of drive ring 51 and
formed with notches 128 and 129, respectively, which open
-36-
~64~9
generally tangentially in respect to ring 51 in the
direction opposed to the direction of turning of ring Sl
for effecting a loading operation.
As shown on Fig. 26, positioning plates 34
and 35 are supported at different heights or elevations
hl3 and hl4 above ring 51 so that, during a loading
operation, the guiding element 18, in its so-called risen
position determined by the engagement of its stop or
lug 114 with the respective adjusted leaf spring 112,
may move under positioning plate 35 and then engage its
end or tip portion 18a in notch 128 of positioning plate
34. More particularly, as shown on Fig. 26, the leaf
springs 112 associated with guiding elements 18 and 19
are adjusted so that such guiding elements, upon being
released from guide 33 and thus free to be swung upwardly
to their respective risen positions shown in dot-dash
lines at 18 and 19, will have their free ends ortip ends
18a and 19a at the heights hlo and hll above ring 51.
As shown, the height hlo is smaller than the height h
by the distance hl2. Further, positioning plate 34 is
~ounted so that its height hl3 above ring 51 is somewhat
smaller than the height hlo, while the other positioning
plate 35 is mounted so that its height hl4 above ring 51
is greater than the height hlo and somewhat smaller than
the height hll.
It will be appreciated that, during a tape
loading operation initiated by rotation of ring 51 in
the clockwise direction as viewed on Fig. 8, the tape
guiding elements 18 and 19, after emerging from under
4~
guide 33, extend upwardly through slot 46 of track
member 44 and are maintained in their risen conditions,
indicated in dot-dash lines at 18 and 19 on Fig. 26
while moving horizontally in the direction of the arrow F
toward their respective operative positions. Thus,
guiding element 18 in its risen condition or state
moves under positioning plate 35 and, as guiding elements
18 and 19 near their respective operative positions,
their respective tip or free ends 18a and l9a are
received in notches 128 and 129, respectively, of
positioning plates 34 and 35 and abut against the closed
ends 128a and 129a of the respective notches. After
such abutment of tip ends 18a and l9a against the closed
ends 128a and 129a of the respective notches, ring 51
undergoes a final increment of movement in the direction
of arrow F on Fig. 26. During this final increment of
movement of ring 51, corresponding movements ofthe tip
or free end portions 18a and l9a of guiding elements 18
and 19 are prevented and, therefore, guiding elements 18
and 19 are pivoted about their respective pivot pins 108
in the clockwise direction, as viewed on Fig. 26. When
the movement of ring 51 in the direction of arrow F has
ended, the operatively positioned guiding elements 18
and 1~ are in precisely predetermined respective angular
positions relative to chassis 5, as indicated in solid
lines on Fig. 26. It will be apparent that, such
pivotal movements of guiding elements 18 and 19 to their
operative positions as a result of the final increment of
-38-
89
rotation of ring 51 are resisted by the respective leaf
springs 112. Thus, for example, as shown on Fig. 20,
when guiding element 18 is moved from its risen position
shown in full lines to its operative position indicated
in dotted lines at 18" on Fig. 20, leaf spring 112 has
its free end 112a flexed or deflec~ed downwardly to the
position indicated in dotted lines. Accordingly, at the
completion of the movement of ring 51, each of guiding
elements 18 and 19 is firmly and stably secured in its
respective operative position by the spring 112 acting
resiliently against the stop or lug 114 at the lower end
of the guiding element 18 or 19, and by the positioning
plate 34 or 35 acting against the upper or tip end 18a
or l9a of the guiding element.
Referring now to Fig. 27, it will be seen that,
when drive ring 51 attain~- its final position at the
completion of its rotation in the direction of the arrow
G for effecting a loading operation, a lever 132 which is
pivoted on a pin 133 secured to chassis 5 is effective
to detect the completion of the loading operation and to
secure ring 51 in its respective position. More particu-
larly, lever 132 is shown to be biased in the clockwise
direction, as viewed on Fig. 27, by means of a helical
tension spring connected between one end of lever 132 and
chassis 5. The opposite end of lever 132 carries a
rotatable roller 135 which is urged at all times against
the periphery 136 of ring 51 by the action of spring 134
on lever 132. A switch 137 for detecting the end of a
-39-
~64~89
loading operation is mounted on chassis 5 adjacent lever
132, and an operating lever 138 is pivoted at a fulcrum
139 and confronts an actuator 137a of switch 137. A
tension spring 140 is connected between operating lever
138 and chassis 5 and urges lever 138 in the direction
to engage its free end portion 138a with a lug 141 on
lever 132. Drive ring 51 has a locking detent or recess
142 in its periphery at a location to receive roller 135
when ring Sl is in its final position upon the completion
of a tape loading operation. In any other position of
ring 51, roller rides on the peripheral surface of ring
51 and, accordingly, pivots ~ever 132 in the counterclockwise
direction against the force of spring 134 from the
position shown in full lines on Fig. 27, to the position
indicated in broken lines at 132'. Pivoting of lever
132 to the position indicated at 132' causes lug 141 to
act on operating lever 138 for pivoting the latter in the
clockwise direction about fulcrum 139, whereby actuator
137a of detecting switch 137 is extended to turn OFF the
switch. On the other hand, when ring 51 is turned in the
direction of the arrow G on Fig. 27 and reaches the
position shown in full lines at the completion of a
loading operation, the engagement of roller 135 in detent
142 locks ring 51 in such position, and the resulting
pivoting of lever 132 in the clockwise direction by spring
134 moves lug 141 away from operating lever 138 so that
spring 140 can cause the latter to depress actuator 137a
-40-
~16~#9
and thereby turn ON detecting switch 137. Thus, switch
137 detects the completion of a tape loading operation.
It will be seen that, at the side of detent 142 extending
in the direction G of the rotation of ring 51 for a
tape loading operation, ring 51 has an inclined ramp 142a
extending from the bottom of detent or recess 142 to the
outer periphery of the ring. Thus, when drive ring 51 is
turned in the direction opposite to that indicated by
the arrow G on Fig. 27 from the position shown in full
lines on that view, that is, when ring 51 is turned in the
counterclockwise direction for initiating a tape unloading
operation, roller 135 ascends the inclined ramp 142a to
again ride on the outer periphery of ring 51, whereby
lever 132 i8 again pivoted to the position indicated in
broken lines at 132' and detecting switch 137 is turned OFF.
Referring now to Fig. 28, it will be seen that,
in order to detect the completion of a tape unloading
operation of the apparatus according to this invention,
a lever 144 is pivotally mounted on a pivot 145 which is
carried by track member 44 near to the path of movement
of base portion 56 when the guiding elements 16 and 17
thereon are near their initial positions indicated at 16'
and 17' on Fig. 1. A tension spring 146 is connected
between lever 144 and an anchor on track member 44 for
urging lever 144 in the clockwise direction. A detecting
switch 147 is mounted on chassis 5 below detectin~ lever
144 and has its actuator 147a confronted by an operating
lever 148 which is pivoted at one end on a fulcrum 149
~164~?8g
and urged by a spring 150 to depress actuator 147a and
to engage the free end 148a of lever 148 with a pin 151
depending from one end of detecting lever 144. The
opposite end portion 144a of lever 144 has a pin 152
depending therefro~ and engaging slidably in an arcuate
slot 153 formed in track member 144 so as to limit the
pivotal movement of lever 144. Further, as shown on
Fig. 28, a protuberance 154 extends from the inside edge
portion of upper block 59 of movable base portion 56 and
is positioned to be engaged by the end 144a of detecting
lever 144 when movable base portion 56 and guiding
elements 16 and 17 thereon are in their respective initial
positions shown in full lines on Fig. 28. When protuber-
ance 154 engages lever 144, the latter is turned in the
counterclockwise direction against the force of spring
146 so as to move pin 151 away from operating lever 148,
as shown in full lines on Fig. 28, with the result that
actuator 147a is depressed to turn ON detecting switch
147. However, as indicated with dot-dash lines at 154'
and at 154" on Fig. 28, at the moment when movable base
portion 56 is moved either in the direction of the arrow
I or the arrow H, respectively, from its position shown
in full lines, protuberance 154 moves away from end 144a
of detecting lever 144 and, as a result thereof, spring
146 pivots lever 144 in the clockwise direction so that
pin 151 acts against operating lever 148 to move the latter
away from actuator 147a and thereby turn OFF detecting
switch 147.
-42-
4~89
~ eferring now to Figs. 29-31, it will be seen
that tape guiding element 20 and pinch roller 21 of the
take-up side loading unit 15 are mounted on a movable
base 157 which is adapted to be moved horizontally in
an arcuate path on chassis 5. Movable base 157 is
desirably comprised of elongated, laterally curved lower
and upper slide plates 158 and 159. Lower slide plate
158 is guided by a plurality of slide guides 160 which
are desirably molded from a synthetic resin or the like
and fixedly mounted on chassis 5 at spaced apart
locations along the inner and outer margins of the
desired arcuate path of travel of plate 158. Upper slide
plate 159 is disposed horizontally above slide plate 58
iIl parallel with the latter and has a pair of elongated
arcuate apertures 163 and 164 at spaced apart locations
along plate 159 to slidably receive guide pins 161 and
162, respectively, extending from lower slide plate 158.
Thus, upper slide plate 159 can move longitudinally to
a limited extent relative to lower slide plate 158.
Upper slide plate 159 is urged in the direction of the
arrow J on Fig. 30 relative to lower slide plate 158 by
means of a helical tension spring 166 which is received
in an elongated cut out 167 in upper plate 159 and
connected, at its ends, to upper slide plate 159 and to
an anchor pin 165 extending from lower slide plate 158.
The longitudinal movement of upper slide plate 159
relative to lower slide plate 158 in the direction of
arrow J under the urging of spring 166 is limited by the
-~3-
~16'i~S19
engagement of ends of elongated apertures 163 and 164 with
the respective pins 161 and 162 A rack 168 is formed
along the inner longitudinal edge of upper slide plate
159 so that movable base 157 may be longitudinally
driven, as hereinafter described in detail.
The tape guiding element 20 includes a rotatable
roller 170 which corresponds to the roller 72 of the
movable tape guiding element 16, and which is similarly
rotatably mounted on a supporting shaft 171 by means of
a height adjusting unit 172 of essentially the same
construction as the height adjusting unit 75 for element
16 which has been previously described in detail with
reference to Fig. 14. The supporting shaft 171 for roller
170 of tape guiding element 20 is mounted in an erect or
perpendicular position on lower slide plate 158 near to
to the end of upper slide plate 159 which has slot 163
therein.
Pinch roller 21 is shown to be rotatably mounted
on a supporting shaft 175 which extends vertically
between upper and lower end portionsor arms 174aand 174b ofa
substantially U-shaped pinch roller supporting lever 174.
Supporting lever 174 is pivotally mounted on a vertical
pivot shaft 176 extending from an end portion of lower
slide plate 158. A torsion spring 177 is provided around
shaft 176 to urge pinch roller supporting lever 174 to
pivot in the clockwise direction, as viewed on Fig. 30,
and such pivotal movement of lever 174 is suitably
restricted, for example, by the abutment of lower end
of the shaft 175 with a stop or projection 178 formed on
-44-
11t~i4~?~1g
the upper surface of slide plate 158. If movable tape
guiding element 20 and pinch roller 21 are in their
initial or original positions indicated in broken lines
at 20' and 21' on Fig. 1, upper slide plate 159 may be
moved longitudinally in the direction of arrow K on
Fig. 30, as will be hereinafter described in detail,
with the result that lower slide plate 158 is similarly
pulled by spring 166 so as to move horizontally on
chassis 5 in the path defined by guides 160. Thus,
guiding element 20 and pinch roller 21 are moved to their
operative positions shown in full lines on Fig. 1.
When movable base 157 is returned in the direction of
arrow J in the course of a tape unloading operation, the
ends of apertures 163 and 164 of plate 159 abut guide
pins 161 and 162, respectively, whereby lower slide plate
158 is correspondingly moved for returning guiding
element 20 and pinch roller 21 to their initial or
original positions.
Referring now to Figs. 32 and 33, it will be
seen that the head of guide pin 161 is formed with a
conical top surface 180, and that a locking plate 181 is
supported, at its opposite sides, on posts 182 extending
upwardly from chassis 5 so that plate 181 will span the
path of movable base 157 adjacent the position of pin
161 at the completion of a tape loading operation. The
locking plate 181 has an inclined portion 183 extending
centrally therefrom so as to be engageable by the conical
surface 180 on the head of guide pin 161. The inclined
portion 183 of plate 181 and the conical head surface
180 on guide pin 161 cooperate to provide a locking
-45-
~64~39
mechanism 184 ~y which tape guiding element 20 is
securely and stably located in its operative position
shown on Fig. 1. More particularly, when movable base
157 is moved in the direction of arrow K to its
operative position in the course of a tape loading
operation, the conical head surface 180 of guide pin
161 engages the lower surface of the inclined portion
183 of plate 181 to provide a wedge effect by which
plates 159 and 158 are made to bear downwardly against
each other and against the bearing surfaces on guides
160. In this case, the driving force in the direction
of the arrow K on upper slide plate 159 is transmitted
to lower slide plate 158 through spring 166 which is
placed under tension and thereby provides a continuing
force by which the conical head surface 180 of guide
pin 161 maintains bearing contact with inclined portion
183 of plate 181.
As shown on Figs. 34, 37 and 38, in the operative
position of movable base 157, pinch roller 21 is disposed
adjacent to capstan 23 and also adjacent to pinch roller
pressing unit 37 which is operative, in the recording
or reproducing mode of the VTR, to press pinch roller 21
against rotated capstan 23 with the tape 4 therebetween
for driving the tape. In the illustrated embodiment,
pressing unit 37 is shown to include upper and lower
pressing levers 186 and 187 pivotally mounted, at one
end, on a shaft 188 which extends upwardly from chassis
5. The levers 186 and 187 have upper and lower rollers
189 and 190, respectively, rotatably mounted thereon, and
vertically disposed so as to be at the same heights above
-46-
~164~9
chassis S as the upper and lower arms 174a and 174b,
respectively, of the pinch roller supporting lever 174.
The free ends of pressing levers 186 and 187 are
connected by a vertical pin 191 on which there is
pivoted a first toggle link 192. The toggle link 192
is, in turn, connected with a second toggle link 193
by means of a connecting pin 194. A limiter arm 195
(Figs. 34-38) is connected, intermediate its ends, with
toggle link 193 by means of a pivot pin 196, and is
pivotally supported on a fixed base 197 extending from
chassis 5 by means of a pivot pin 198 engaging one end
of arm 195. The limiter arm 195 is urged to pivot in
the counterclockwise direction, as viewed on Figs. 34
and 36-38, by a helical tension spring 200 which is
connected between the end of arm 195 remote from pivot
pin 198 and a spring force adjusting plate 199 which,
as shown particularly on Fig. 34, is adjustably mounted
on locking plate 181. As particularly shown on Fig. 36,
the adjustable mounting of plate 199 may be effected
by providing such plate with elongated slots 199a which
receive a pin 199b and a screw l99c extending from
locking plate 181. Thus, screw l99c may be loosened
to permit displacement of plate 199 in the direction for
either increasing or decreasing the tension of spring
200. The pivotal movement of limiter arm 195 by spring
200 is restricted by the abutment of arm 195 with a
stop or projection 201 formed on plate 199. Thus, the
described adjustment of plate 199 also determines the
initial or rest position of limiter arm 195.
-47-
A solenoid 202 (Figs. 5 and 34) is mounted on
chassis 5 through a plurality of supporting posts 203
(Fig. 34), and has an armature 204 pivotally connected,
as at 205, to one end of a link 206 which has its
other end pivotally connected to the pin 194 between
toggle links 192 and 193. Solenoid 202 is of the
type in which armature 204 is normally extended longi-
tudinally by means of a helical compression spring 207,
and such armature is retracted or drawn into the
housing of solenoid 202 against the force of spring 207
only when the solenoid 202 is energized.
When movable base 157 is in its original
position, as shown on Fig. 36, lower pressing roller
190 of unit 37 bears against the outside edge of upper
slide plate 159, that is, the edge opposite to rack
168, and upper and lower pressing levers 186 and 187
are thereby urged in the clockwise direction as viewed
on Fig. 36. When movable base 157 is moved to its
operative position, as shown on Fig. 37, lower pressing
roller 190 moves off upper slide plate 159 and the
upper and lower rollers 189 and 190 come into contact
with the upper and lower arms 174a and 174b of pinch
roller supporting lever 174. Thereafter, when solenoid
202 is energized for establishing the recording or
reproducing mode of the VTR, armature 204 is retracted
so that connecting link 206 pulls pivot pin 194 in the
direction of the arrow L on Fig. 34 and, accordingly,
toggle links 192 and 193 are urged in the directions of
-48-
4~9
the arrows M and N, respectively. Thus, upper and lower
pressing levers 186 and 187 are pivoted in the direction
of the arrow O and the respective rollers 189 and 190
act against the upper and lower arms 174a and 174b for
pivoting pinch roller supporting lever 174 in the
direction of the arrow Q against the force of torslon
spring 177 with the result that pinch roller 21 is
brought into contact with capstan 23 with the tape ~
therebetween. After such contact of pinch roller 21 with
capstan 23 has been established, further movement of
pivot pin 194 in the direction of arrow L is accompanied
by pivoting of limiter arm 195 in the direction of the
arrow P, that is, so as to move arm 195 away from stop
201 against the force of spring 200. Accordingly, the
adjusted tension of spring 200 determines the pressure
with which pinch roller 21 is urged against capstan 23
with the tape 4 therebetween during a recording or repro-
ducing operation.
~ rnen solenoid 202 is de-energized to halt a
recording or reproducing operation, spring 2~7 is
effective to extend armature 204 with the result that
connecting link 206 moves pivot pin 194 in the direction
counter to the direction of arrow L on Fig. 34, whereby
pressing levers 186 and 187 are turned in the clockwise
direction from the position shown on Figs. 34 and 38 to
the position shown on Fig. 37, with the result that pinch
roller supporting lever 174 is turned by torsion spring
177 (Figs. 29 and 31) for moving pinch roller 21 away
from capstan 23. Thereafter, if movable base 157 is
-49-
returned to its original position, lower roller 190 is
again engaged by the outer side of slide plate 159 so
that upper and lower pressing rollers 189 and 190 are
separated from pinch roller supporting lever 174.
By reason of the inclusion in pinch roller
pressing unit 37 of the toggle mechanism constituted
by toggle links 192 and 193 and -.he connecting link 206,
pinch roller 21 can be strongly pressed against capstan
23 even if a relatively small solenoid 2~2 providing a
correspondingly weak retracting force on its armature 204
is employed for minimizing the power requirements thereof.
Furthermore, although the upper and lower pressing
levers 186 and 187 are mounted on a common shaft 188,
such levers are capable of slight angular displacements
relative to each other. Thus, in the operative
condition of pressing unit 37 (Fig. 38), upper and lower
rollers 189 and 190 are able to independently act against
the upper and lower arms 174a and 174b, respectively,
of pinch roller supporting lever 174 for urging pinch
roller 21 into contact with capstan 23 with a uniform
pressure therebetween at the top and bottom of the pinch
roller.
Referring now to Figs. 39 and 40, it will be
seen that, in the illustrated embodiment of the invention,
the driving unit 36 for driving both the feed side
loading unit 14 and the take up side loading unit 15
includeq driving gears 211 and 212 which are suitably
rotatably mounted on chassis 5 between ring 51 and
movable base 157, and which respectively mesh with and
-50-
1164~9
drive the peripheral gear 53 of ring 51 and the rack
168 on upper slide plate 159. A pinion 213 is
rotatable coaxially with gear 211 and meshes with an
idler gear 214 which is integral, or rotatably coupled
with a coaxial gear 215 meshing with gear 212. Gears
213, 214 and 215 provide a reduction gearing for
transmitting the rotation of driving gear 211 to driving
gear 212. A reversible electric motor 216 is mounted
on chassis 5 and has its shaft 217 rotatably coupled
by a belt and pully transmission 219 with an idler
shaft 220a which is, in turn, rotatably coupled through
a reduction gear transmission 220 with a drive shaft
220b. Finally, a gear 218 secured on drive shaft 220b
meshes with gear 211.
It will be apparent that, when motor 216 is
operated, gear 218 is driven in one direction or the
other by way of belt and pully transmission 219 and gear
transmission 220 so that driving gear 211 is driven in
mesh with gear 53 on ring 51 for effecting a tape loading
or unloading operation by feed side loading unit 14,
while simultaneously the other driving gear 212 is driven
at a reduced speed in mesh with gear 168 on movable
base 157 for similarly effecting a tape loading or
unloading operation of take-up side loading unit 15.
More particularly, in response to forward rotation of
motor 216, both gears 211 and 212 are rotated in the
direction of arrows R on Fig. 40 so as to rotate ring
51 in the clockwise direction on Fig. 8 and, at the
same ~ime, to move base 157 in the direction of the
-51-
~1~4~
arrow K on Fig. 30, whereby a tape loading operation is
performed by units 14 and 15. It will be appreciated
from a consideration of Fig. 1 that, in the course of
a tape loading operation, the tape guiding elements 16
and 17 of feed side loading unit 14 move a substantially
greater distance from their initial positions to their
operative positions than do the tape guiding element 20
and pinch roller 21 of take-up side loading unit 15.
Therefore, driving gear 211 is rotated at a substantially
greater speed than driving gear 212, for example, gears
213-215 may provide a 4:1 reduction ratio from gear 211
to gear 212 so that ring 51 is moved at a speed four
times the speed of movement of movable base 157. The
completion of the tape loading operation is detected by
detecting switch 137 (Fig. 27) which is effective to
halt the operation of motor 216.
When it is desired to provide a tape unloading
operation, motor 216 is operated in the reverse direction
so that driving gears 211 and 212 are both rotated in the
direction of arrows S on Fig. 40, with the result that
ring 51 is turned in the counterclockwise direction as
viewed on Fig. 8 and, at the same time, movable base 157
is moved in the direction of the arrow J on Fig. 30,
thereby to cause tape unloading operation by units 14 and
15.
The completion of a tape unloading operation is
detected by switch 147 (Fig. 28). Preferably, when
movable base portion 56 of feed side loading unit 14
has been moved back in the direction of the arrow H to
the position where its protuberance 154 acts on detecting
lever 144 to turn ON detecting switch 147, the operation
of motor 216 in the reverse direction is continued.
However, when the protuberance reaches the position
shown in broken lines at 154", that is, when detecting
switch 147 is turned OFF after having been first turned
ON, the direction of rotation of motor 216 is changed
over from reverse to forward, so that movable base
portion 56 is now moved in the direction of the arrow I.
When the protuberance 154 again reaches the position
shown in full lines on Fig. 28, and at which protuberance
154 acts on lever 144 to again turn ON switch 147,
the operation of motor 216 is halted. It will be
appreciated that the foregoing operations of motor 216
can be achieved with a suitable control circuit (not
shown) which is triggered when switch 147 is first
turned ON during reverse operation of motor 216, so as
to cause change-over of motor 216 to forward operation
a predetermined time thereafter, and which finally halts
the operation of motor 216 the next time switch 147 is
turned ON, with the driving circuit for motor 216 then
remaining in the condition for forward operation of the
motor. Of course, at the completion of the tape unloading
operation, movable base 157 of the take-up side loading
unit 15 also undergoes a very small movement, for example,
of three or four mm, beyond its original position in the
reverse direction, and then a corresponding small movement
in the forward direction to its original position.
-53-
1.~64~39
Referring now to Figs. 41-44, it will be seen
that a substantially horizontal supporting plate Z24 is
mounted on the upper ends of tape guides 24a and 26 and
of a support rod 223 which extends upwardly from chassis
5. At one end portion of supporting plate 224, a head
mounting plate 225 is mounted thereon so as to be
adjustable in the horizontal direction. The audio
erase head 28 and the combined audio and CTL recording
and reproducing head 29 are suspended from head mounting
plate 225 by way of a head adjusting plate 226 so as to
permit adjustment of the height and azimuth of the heads
28 and 29. The head shielding tape guides 38 and 39
formed, for example, of a sythetic resin, are respectively
attached to the upper portion of head mounting plate
225 and to the upper portion of supporting plate 224 in
the vicinity of tape guide 26. Dowels 227 and 228
projecting integrally from the lower surfaces of guides
38 and 39 are engaged in holes 229 and 230 formed in
head mounting plate 225 and in supporting plate 224,
respectively, for positioning guides 38 and 39 which
are then secured by means of screws 231 and 232. At the
sides of guides 38 and 39 which face toward the operatively
positioned cassette 1, guides 38 and 39 are formed with
inclined faces 233 and 234, respectively, down which
the tape 4 can slide. The lower edges or margins of
these inclined faces 233 and 234 are either flush with,
or overhang the edge 224a at the corresponding side of
supporting plate 224. A plurality of holes 235 are
formed vertically in guides 38 and 39 to permit tools,
-54-
~6~39
such as a screw driver or the like, to be inserted
therein for effecting various adjustments of heads 28
and 29 and of tape guide 26 following the mounting of
guides 38 and 39.
When a cassette 1 is brought down horizontally
to its loaded or operative position, as known hereto-
fore, the lower edge 9a of its lid 9 is brought into
contact, at one side of the lid, with a lid raising
element 236 which is suitably mounted on chassis 5, as
shown in Fig. 43. Therefore, in the course of the
downward movement of cassette 1, element 236 raises
lid 9 to its opened position, as shown on Fig. 44. It
will be appreciated that the lid 9 is at least partially
opened before the downward movement of cassette 1 to
its operative or loaded position is completed 30 that,
if the tape run 4' indicated in broken lines on Fig. 1
is loose, the inherent elasticity of the tape will cause
the latter to be urged against the inner surface of
lid 9 and, as the lid 9 is opened to a certain extent,
the tape 4 may spring out through the front opening 8
of the cassette. In the absence of guides 38 and 39,
if the tape 4 springs out of cassette 1 before the
movement of the latter to its loaded or operative
position is completed, the tape may become entangled
with the heads 28 and 29 or guide 26 with serious damage
to the tape resulting therefrom.
However, by reason of the presence of guides
38 and 39, if the tape 4 springs from the opening 8 of
a casse~te 1 during the opening of lid 9 in response to
-55-
~164~9
the downward movement of the cassette to its operative
or loaded position, such accidentially released tape
will slide down the inclined faces 233 and 234 and be
pushed back toward cassette 1. Thus, even if the
tape accidentally springs out of cassette 1, the
er.tangling of the tape with heads 28 and 29 or tape
guide 26 is avoided to prevent damage to the tape.
Furthermore, as is known and shown on Figs. 43 and 44,
a tape presser 238 of substantially inverted L-shaped
cross section is formed integrally with the body or
housing 237 of cassette 1 so as to be disposed inside
front lid 9 with the tape 4 therebetween in the closed
position of the lid. Therefore, if at the time of the
cassette loading operation the tape 4 is deflected back
toward cassette 1 by guides 38 and 39, such deflected
tape will abut against tape presser 238 and thereby be
prevented from moving too deeply into cassette 1.
Consequently, as a cassette 1 is moved horizontally
downward to its loaded or operative position, the run
4' of tape 4 is inserted safely and smoothly into a very
narrow gap, for example, as indicated at 239 on Fig. 41,
defined between the rising motion guide 33 and the tape
guide 26. Further, the presence of the guides 38 and 39
for slidably guiding the tape 4 during the loading of
the cassette 1 makes it possible to make relatively
small the gap 12 (Fig. 2) between the front face la of
the loaded or operatively positioned cassette 1 and the
drum 13.
-56-
~64~t'39
Referring now to Figs. 45-47, it will be seen
that the tension detector 40 includes a tension detecting
lever 242 pivotally mounted intermediate its ends on a
movable base 243 by means of a vertical pivot pin 244,
and having the tension detecting pin 30 depending from
one ènd of lever 242. Movable base 243 is pivotally
mounted on a vertical pivot pin 245 which is mounted on
chassis 5 and is offset relative to pivot pin 244. Base
243 is biased in the counterclockwise direction, as
viewed on Fig. 46, by means of a helical tension spring
246 which extends between a tab 246a struck from movable
base 243 and an anchor pin 246b secured to chassis 5
(Fig. 45). A projection 247 at one side of one end of
movable base 243 adjacent the bottom of the latter is
adapted to abut against an end portion 248 of the lever
132 which detects the completion of a loading operation.
Thus, when drive ring 51 is in any position other than
that corresponding to the completion of a tape loading
operation, for example, as on Fig. 46, roller 135 rides
on the periphery 136 of ring 51 and the resulting position
of lever 132 causes its end portion 248 to act against
projection or abutment 247 for angularly displacing
movable base 243 in the clockwise direction to the
position shown on Fig. 46 against the force of spring 246.
However, at the completion of a tape loading operation,
at which time roller 135 on lever 132 engages in recess
142 of ring 51, as on Fig. 47, end portion 248 of lever
132 moves away from projection or abutment 247 and spring
246 angularly displaces movable base 243 to the position
-57-
shown on Fig. 47. The tension detecting lever 242 is
pivotally biased in the counterclockwise direction, as
viewed on Fig. 46, with respect to movable base 243 by
means of a helical tension spring 249 stretched between
detecting lever 242 and movable base 243. A pin 250
depending from tension detecting lever 242 is loosely
engaged in a hole 251 formed in movable base 243 for
limiting the angular range of displacement of detecting
lever 242 relative to movable base 243. The spring 249
is designed to be much weaker than the spring 246.
The end of tension detecting lever 242 remote
from pin 30 carries a permanent magnet 252 which is
in close proximity to a magneto-resistance sensor 253
provided on a printed circuit board 254 carried by the
adjacent end portion of movable base 243, The opposite
end portion of movable base 243 carries a balancer 255
for balancing the magneto-resistance sensor 253.
In the VTR to which the tape loading apparatus
according to this invention is shown applied, the reel
mounts 6 and 7 are driven directly by respective
independently controlled motors (not shown), that is,
the rotating shaft of each reel mount is integral with
the respective motor shaft. The tension detector 40 is
inten~ed to electrically detect the tension in the tape
4 between the supply or feed reel 2 and drum 13 while
the tape is being driven at a substantially constant
speed in the recording or reproducing mode of the VTR.
When a change in the tape tension is detected, tension
~164~89
~detector 40 correspondingly controls the rotational speed
of the motor associated with feed reel mount 6 for
thereby maintaining the back tension of the tape at
a constant value.
In the unloaded condition of the apparatus
according to this invention, that is, at the completion
of a tape unloading operation thereof, detector 40 is
in the condition shown on Fig. 46. As previously noted,
in such condition, roller 135 of lever 132 engages the
outer peripheral surface 136 of ring 51 so that projection
247 of movable base 243 is displaced by end portion 248
of lever 132 for pivoting movable base 243 in the clock-
wise direction against the force of spring 246. Thus,
tension detecting lever 242 is maintained in a stand-by
or non-operative position in which the depending tension
detecting pin 30 is spaced sufficiently from the loading
path of tape 4 so as to avoid any interference with the
loadin~ operation by feed side loading unit 14.
Upon the completion of the loading operation,
tension detector 40 assumes the condition shown on
Fig. 47, that is, roller 135 on lever 132 enters detent
142 and, as a result, spring 246 can pivot movable base
243 in the counterclockwise direction and tension
detecting lever 242 is moved to its operative position
shown in full lines on Fig. 7, and in which tension
detecting pin 30 is brought into contact with tape 4
between guide pin lb in cassette 1 and tape guiding
element 19.
_59_
~64~19
In such operative state of tension detector 40,
as tape 4 is moved longitudinally at a constant speed in
the recording or reproducing mode of the VTR, tension
detecting pin 30 is moved within the range indicated
between the positions of the pin shown in broken lines
at 30' and 30" in accordance with changes in the tape
tension. More particularly, as the tape tension is
reduced, lever 242 is pivoted counterclockwise by spring
249 and pin 30 is thereby moved to the position indicated
at 30". Conversely, if the tape tension is increased~
tension detecting lever 242 is pivoted in the clockwise
direction against the force of spring 249 and tension
detecting pin 30 is thereby moved to the position indi-
c~ted at 30', It will be appreciated that the described
pivotal movements of tension detecting lever 242 relative
to base 243 will cause corresponding movements of magnet
252 in respect to magneto-resistance sensor 253, with
the result that the extent of the pivotal movement of
tension detecting lever 242, and hence the change in
tape tension, is electrically detected by sensor 253.
As earlier noted, the rotational speed of the driving
motor for the feed reel mount 6 is controlled on the basis
of an output of magneto-resistance sensor 253 so as to
maintain a constant tension in the tape.
As also earlier noted, at the commencement of a
tape unloading operation, roller 135 rolls up the inclined
ramp 142_ onto the outer periphery 136 of ring 51,
whereby lever 132 is returned to the position shown
-60-
~i4~t~9
on Fig. 46 for causing pivoting of movable base 243 in the
clockwise direction and thereby causing tension detecting
lever 242 to assume its stand-by or non-operative position
where pin 30 is substantially disengaged from the tape
for avoiding any interference with the tape unloading
operation.
It will be seen that, in the above described
tension detector 40, it is possible to provide a large
angular movement of tension detecting lever 242 between
its inoperative or stand-by position (Fig. 46) and its
operative position (Fig. 47), so as to ensure that tension
detector 40 will not interfere, in any way, with the
tape loading or unloading operations. However, such
large angular displacements of lever 242 between its
inoperative and operative positions does not involve
correspondingly large displacements of magnet 252 relative
to magneto-resistance sensor 253. Therefore, with
tension detecting lever 242 disposed in its operative
positions as a result of movement of base 243 to its
operative position, variations in the tension in the
tape 4 engaged withpin 30 cause correspondingly small
displacements of magnet 252 relative to sensor 253 so
that the tape tension variations can be very accurately
sensed or detected. Thus, the described arrangement of
tension detector 40 accommodates the desirably high
sensitivity of magneto-resistance sensor 253 ~hich can
correctly and accurately detect the amount of movement
of magnet 252 relative to sensor 253 only when such movement
is within a relatively small range.
4~ 9
Referring now to Figs. 48-50, it will be seen
that, as is well known, a cassette 1 to be employed in
the VTR is inserted into a cassette holder 258 in an
elevated position of the latter, whereupon the holder
258 is moved downwardly, while being maintained horizon-
tally, for moving the cassette 1 therein onto reel
mounts 6 and 7 from above. As shown, a substantially
hook-shaped keeper 259 depends from one side of cassette
holder 258 and, during the downward movement of cassette
holder 258 to its operative position, keeper 259 extends
downwardly through an opening 260 in chassis 5 (Figs. 49
and 50). The keeper 259 forms part of the cassette
holder locking unit 41 which further includes a latching
lever 261 pivotally mounted, at its lower end, on a
pivot shaft 262 which is suitably carried by chassis 5.
latching roller 263 is rotatably mounted on a shaft
270 carried by the upper end portion of latching lever
261 and is adapted to engage in a recess 264 of keeper
259 when locking unit 41 is in its engaged condition
(Fig. 49). A slide plate 265 is mounted for longitudinal
sliding along the inner surface of an adjacent side wall
of chassis 5, for example, by means of an elongated slot
266 in slide plate 265 which slidably receives pivot
shaft 262 extending from such side wall of the chassis,
and further by means of a projection 267 extending from
the side wall of the chassis and engaged in another
elongated slot 268 in slide plate 265. Latching lever
261 is urged to pivot in the counterclockwise direction,
-62-
as viewed on Fig. 49, by a helical tension spring 269
connected between lever 261 and chassis 5. One end of
shaft 270 is engagable by a projection of 271 extending
upwardly from an end portion of slide plate 265 for
restricting the counterclockwise pivoting of lever 261
by spring 269. Sliding of plate 265 toward the left,
as viewed on Fig. 49, under the influence of spring
269 acting on lever 261 is limited by the engagement
of one end of elongated aperture 268 with the guiding
projection 267.
As shown particularly on Fig. 48, an elongated
slide 272 extends laterally under chassis 5 and is
slidably mounted in respect to the latter. Slide 272 has
one end 272a extending adjacent to the original or
initial position of movable base 157 for engagement by
an end 273 for lower slide plate 158. The opposite end
272b of slide 272 is connected by a pivot pin 276 with
one arm 275a of a bell crank 275. The bell crank 275 is
mounted, between its arms 275a and 275b, on a pivot pin
274 carried by chassis 5 for swinging in a horizontal
plane below the chassis. The free end portion of arm
275b of the bell crank 275 is accommodated between spaced
projections 277 and 278 and projecting upwardly from the
end portion of slide plate 265 remote from projection 271.
The cassette holder locking unit 41 operates
as follows:
Starting with cassette holder 258 in its elevated
or cassette-receiving position and with loading units 14
-63-
4QF~9
and 15 in their initial positions indicated at 14' and
15' on Fig. l, it will be seen that latch lever 261 and
slide plate 265 occupy the positions shown in full lines
on Figs. 48 and 49. When a cassette 1 is inserted in the
elevated holder 258 and the latter is moved downwardly
to its operative position, an inclined edge 279 on
keeper 259 acts against roller 263 to temporarily angu-
larly displace lever 261 in the clockwise direction, as
viewed on Fig. 49, until keeper 259 is disposed under
roller 263, whereupon spring 269 is operative to return
lever 261 in the counterclockwise direction for engaging
roller 263 in recess 264, as shown in full lines on
Fig. 49. With roller 263 thus engaged in recess 264 of
keeper 259, cassette holder 258 with a cassette therein
is locked in its operative position.
In response to movement of cassette holder 258
to its lowered or operative position, a suitable detecting
switch (not shown) mounted on chassis 5 may be turned ON
for automatically initiating a tape loading operation of
the apparatus according to this invention. On the other
hand, actuation of an eject push-button (not shown) may
be effective to initiate a tape unloading operation of
the apparatus.
At the completion of the tape unloading operation,
movable base 157 of take-up side loading unit 15 moves
in the direction of the arrow J on Fig. 48 to the position
indicated at Pl, at which position end 273 of lower slide
plate 158 abuts against the adjacent end 272a of slide 272
-64-
~164~
and pushes the latter longitudinally in the direction of
the arrow V to the position indicated in broken lines at
272'. As a result of the foregoing, bell crank 275 is
angularly displaced in the direction of the arrow W to
the position indicated in broken lines at 275' on Fig. 48,
which causes slide plate 265 to be longitudinally dis-
placed in the direction of the arrow X to the position
shown in full lines on Fig. 50. Such longitudinal
displacement of plate 265 causes its projection 271 to
act against shaft 270 for pivoting lever 261 in the
direction of the arrow T, whereby roller 263 is disengaged
from recess 264 of keeper 259 for unlocking cassette
holder 258. Upon unlocking of cassette holder 258, the
latter is returned upwardly to its elevated position at
which the cassette 1 is ejected from the holder, as is
well known
Immediately after roller 263 has been disengaged
from recess 264 to release keeper 259 and permit the
initiation of upward movement of holder 258, movable base
157 of loading unit 15 is moved in the direction of the
arrow K on Fig. 48 through a small distance llo, for
example, of 3-4 mm, as previously described, before finally
coming to rest in its initial or stop position P2. When
movable base 157 comes to rest at the position P2, slide
272, bell crank 275 and slide plate 265 are all free to
be returned to the positions shown in full lines on Fig. 48,
and spring 269 is effective to return lever 261 and
roller 263 in the direction of the arrow U on Fig. 50
to the positions indicated in broken lines. With roller 263
4~9
and latch lever 261 thus positioned, locking device 41
is again in condition to lock holder 258 when the latter
is again lowered to its operative position. It will be
appreciated from the foregoing, that the releasing of
cassette holder locking unit 41 and the return thereof
to its operative condition are made responsive to
movements of the movable base 157 of loading unit 15
through a relatively simple mechanism constituted by
slide plate 265, bell crank 275 and slide 272.
Referring now to Figs. 51-53, it will be seen
that the guide drum 13 of a VTR provided with a tape
loading apparatus according to this invention desirably
has a tape pressing unit 282 mounted thereon. As is
well known, drum 13 may include a lower stationary drum
portion 283, an upper stationary drum portion 284 and
an intermediate rotary drum portion 285 having a rotary
magnetic head 286 attached to its peripheral surface to
extend outwardly through a circumferential gap between
the stationary drum portions 283 and 284 for recording or
reproducing video signals on the tape 4 when the latter
is wrapped or wound helically about the periphery of
drum 13. In order to precisely establish the helical path
of the tape 4 on the peripheral surface of drllm 13, lower
stationary drum portion 282 is provided, on its outer
peripheral surface, with an inclined guiding ledge 288
against which the lower longitudinal edge 287 of tape 4
is urged by the downward pressing action of unit 282 on
the upper longitudinal edge 289 of the tape.
-66-
The illustrated tape pressing unit 282 is shown
to comprise a pair of tape pressing elements 290a and
290b which are desirably molded from a suitable synthetic
resin, and which are accommodated in respective slits
292a and 292b of a holder 291 rixed on top of upper
stationary drum portion 284 so that outer end portions
of elements 290a and 290b project over edge 289 of the
tape wrapped on drum 13. Holder 291 is formed with internal
ridges 293 which are received in corresponding recesses
294 provided in the lower edges of pressing elements 290a
and 290b adjacent the inner ends of the latter, and such
ridges 293 define fulcrums about which tape pressing
elements 290a and 290b can pivot in respective substantially
vertical planes. A horizontal pin 295 is mounted within
holder 291 at a location between pressing elements 290a
and 290b, and a torsion spring 296 is wound around such
pin 295 and has legs 296a and 296b which are engaged, at
their ends, in recesses 297 formed in the upper edges of
elements 290a and 290b at locations spaced outwardly from
recesses 294. The legs 296a and 296b of spring 296 act
downwardly on pressing elements 290a and 290b so that the
latter are pivotally biased in the counterclockwise
direction, as viewed on Fig. 53. Further, as shown on
Fig. 53, each of the pressing elements 290a and 290b has
a beveled corner at the bottom of its outer end portion so
that, when the tape 4 is being wrapped about the outer
peripheral surface of dru~ 13 during a ta~e loading
operation, the upper longitudinal edge 289 of the tape
acts against such beveled corner of each of the pressing
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elements 290a and 290b for deflecting the latter upwardly
and thereby ensuring that, at the conclusion of the tape
loading operation, the lower edges of both pressing
elements will engage, and act downwardly upon edge 289.
It will be apparent that, thereafter, the pressing elements
290a and 290b will exert relatively light elastically
applied pressures downwardly on tape edge 289 at locations
spaced apart along the latter so that the lower
longitudinal edge 287 of the tape will accurately conform
to the guiding ledge 288, that is, will not float away
from the latter, as the tape is being longitudinally
advanced or driven during a recording or reproducing
operation.
Referring now to Figs. 54-56, it will be seen
that, in addition to the rising motion guide 33 and the
guide depressing plate 54 for controlling the swinging
movements of collapsible tape guiding elements 18 and 19
during tape loading and unloading operations, the apparatus
according to this invention is further preferably provided
with an arcuate guide plate 300 which is operative to
control the rate at which guiding elements 18 and l9 rise
when being drawn out of the cassette 1 while in engagement
with the tape 4 in the course of a tape loading operation
and, conversely, for controlling the rate at which tape
guiding elements 18 and 19 are successively swung downwardly
as the same enter the cassette 1 in the course of a tape
unloading operation. More particularly, the arcuate guide
plate 300, which may be suitably mounted under top wall 45
4~9
of track member 44, has an effective arcuate outer edge
portion 301 formed along one end portion of guide plate
300, and being followed by an arcuate cut out 302. The
edge portion 301 of guide plate 300 which extends radially
outward beyond the edge of the latter defined by cut out
302 forms a cam surface which rises gradually in the
direction of the arrow Z on Figs. 54 and 56 to the end
edge 304 at which cut out 302 commences. Each of tape
guiding elements 18 and 19 has a follower pin 303 directed
laterally therefrom so as to be engagable from below with
the cam surface defined by edge portion 301 of plate 300.
In the course of a tape loading operation of
the apparatus, during which drive ring 51 is turned in the
direction of the arrow Z on Fig. 54, and as each of the
tape guiding elements 18 and 19 exits from rising motion
guide 33, the upward swinging motion of such ~uiding
element by its respective spring 111 is controlled by the
engagement of the respective follower pin 303 under edge
portion 301 of guide plate 300. Due to the upward,
gradual inclination of edge portion 301, each of guiding
elements 18 and 19 is gradually raised as it moves out
of cassette 1 in engagement with the tape 4 being with-
drawn from the cassette. As the follower pin 303 of each
of the guiding elements 18 and 19 moves out from under
edge portion 301 at the end edge 304 thereof, such follower
pin can move upwardly in cut out 302 and, therefore, the
respective spring 111 can raise the guiding element 18 or
19 to the respective raised position, for example, as shown
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in broken lines on Fig. 26, and as determined by the
engagement of stop 114 with spring 112. Thereafter,
each of the guiding elements 18 and 19 is moved further
in such raised state until attaining the respective
operative position, as shown in full lines on Fig. 26,
and at which the inclination of the guiding element
18 or 19 is determined by the respective positioning
plate 34 or 35.
Conversely, in the course of a tape unloading
operation during which ring 51 is turned in the direction
of the arrow Y on Fig. 54, the follower pin 303 of each
of the guiding elements 19 and 18, in succession, comes
under edge portion 301 of guide plate 300 at the end
edge 304, as shown on Fig 56, and thereafter the down-
ward inclination of such edge portion 301 causes gradual
downward swinging of the guiding element 18 or 19 as the
latter moves into the cassette 1 and is finally depressed
by guide 33 and then by depressing plate 54.
It will be appreciated that the above described
guide plate 300 represents a very simple structure by
which the swinging movements of tape guiding elements 18
and 19 can be safely and smoothly controlled, particularly
when moving out of and back into cassette 1 in the course
o~ the tape loading and unloading operations, respectively.
Although it is believed that the operation of
the tape loading apparatus according to this invention
will be apparent from the earlier detailed descriptions of
the several components thereof, the operation of the
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~ 164~
tape loading apparatus, as a whole, will be summari~ed
as follows:
Starting with loading units 14 and 15 in their
initial or inoperative positions, as indicated at 14'
and 15' on Fig. 1, and assuming that the placement of
a cassette 1 in holder 258 and the downward movement of
the latter to its operative position will initiate
operation of motor 216 in the direction for turning
gears 211 and 212 in the direction of the arrows R on
Fig. 40 for initiating the tape loading operation, as
previously mentioned, drive ring 51 is thereby turned
in the clockwise direction, as viewed on Fig. 8 with the
result that connecting rod 89 pushes movable base 56
along track member 44. In the course of such movement
of base 56 along track member 44, tape guiding elements
16 and 17 are moved from the original or initial positions
indicated at 16' and 17' on Fig. 1, whereby the tape 4
is withdrawn from the feed side of cassette 1 and wrapped
about drum 13, as shown in full lines on Figs. 1-4. The
described turning of ring 51 in the course of the loading
operation further causes tape guiding elements 18 and 19,
while in their collapsed or supine conditions, to pass
under the tape 4 within cassette 1, and then to successively
rise and engage the tape at the inside of the latter
within the cassette, with such rising motion of elements
18 and 19 being determined by guides 33 and 300, and
with the tape guiding elements 18 and 19 being finally
moved to their respective operative positions shown in
full lines on Fig. 1. In the course of such movements
~64~ 9
of tape guiding elements 16 and 17 to their operative
positions, ring 51 is turned in a horizontal plane on
chassis 5 while the movable base 56 carrying guiding
elements 16 and 17 is moved along a curved path which
is not parallel to the circular path of travel of ring
51, but rather is gradually raised along the inclination
of top wall 45 of track member 44. During the tape
loading operation, the driving force of ring 51 is
transmitted to movable base 56 by way of spring 97 of
connecting rod assembly 89 which accommodates the
different paths of travel of ring 51 and of movable base
56 by relative actual movements of rod 90 and cylinder
91, and by pivoting of ball 101 in socket 102, at one
end of the connecting rod assembly, and further by
pivoting of projections 98 in circular seats 100 a~ the
opposite end of rod assembly 89. By reason of the
foregoing, connecting rod assembly 89 can effect extremely
smooth movement of base S6 along the upwardly inclined
portion of track member 44, while being driven from the
ring 51 turning in a horizontal plane. It will be
appreciated that the path of movement of movable base
56 on track member 44 can be selected independently of
the horizontal path of movement of ring 51 so that the
ring can be easily driven, while the path of the tape
guiding elements 16 and 17 on movable base 56 achieves
the optimum conditions for handling of the tape 4 during
the loading operation. More particularly, the end portion
45a of the top wall 45 of track member 44 which is adjacent
to the operatively positioned cassette 1 can be arranged
horizontal, as previously described, so that the base 56
moves horizontally along such portion 45a with the result
that tape guiding element 16 contacts the run 4' of the
tape in cassette 1 with the axis of guiding element 16
at right angles to the longitudinal median of the tape
and parallel to the surface of the tape. By reason of
such engagement of element 16 with the tape, the latter
can be drawn out from cassette 1 extremely safely and
smoothly, and the exertion of excess force on the tape 4,
such as would result from twisting of the tape, can be
avoided.
As tape guiding elements 16 and 17 near their
operative positions shown in full lines on Fig. 1,
movable base 56 rides onto guide plate 47 and inclined
faces 85 of lower block 61 engage locking pin 86 to
provide a wedge effect so that, in the final operative
positions of guiding elements 16 and 17, the compressive
force of spring 97 in connecting rod assembly 89 urges
the protuberances 84a - 84c tightly against the under-
surface of guide plate 47 for stable positioning of guide
elements 16 and 17.
Simultaneously with the arrival of tape guiding
elements 16 and 17at their operative positions, as
described above, tape guiding elements 18 and 19 also
attain their operative positions shown in full lines on
Fig. 1 and are there securely positioned at predetermined
angles by the respective positioning plates 34 and 35.
Upon the described movements of tape guiding elements 16-19
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~ ~6~ 9
to their respective operative positions, roller 135 on
lever 132 engages in notch 142 of ring 51 for locking
ring 51 in the corresponding position and for causing
switch 137 to detect the end of the tape loading operation.
Upon the completion of the tape loading
operation, the height adjusting unit 75 and the tilt
adjusting unit 82 for tape guiding element 16 can be
conveniently adjusted to ensure that the guiding element
16, in its operative position, has its axis at right
angles to the longitudinal median of the tape and parallel
to the surface of the tape which extends therefrom past
the erasing head 27 and the guide 25 to the peripheral
surface of drum 13.
Simultaneously with the turning of ring 51 by
gear 211 for effecting the tape loading operation of feed
side loading unit 14, gear 212 of drive unit 36, being
rotated in the direction of the arrow R on Fig. 40, drives
upper plate 159 of movable base 157 in the direction of
arrow K on Fig. 30 for effecting the tape loading operation
of take-up side loading unit 15. The movement of plate
159 in the direction of arrow K is transmitted through
spring 166 to lower plate 158 which is correspondingly
moved in the arcuate path lying in a horizontal plane
and being determined by guides 160. Thus, tape guiding
element 20 and pinch roller 21 are moved horizontally
with lower plate 158 from their original positions indicated
in broken lines at 20' and 21' on Fig. 1 to their operative
positions shown in full lines on Fig. 1, whereby loading
of the take-up side of the tape is effected. When tape
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;4~
guiding element 20 and pinch roller 21 attain their
operative positions shown in full lines on Fig. l,the
conical head surface 180 of guide pin 161 engages the
lower surface of inclined portion 183 of plate 181 to
provide the wedge effect under the continued urging of
spring 166, and by which movable base 157 is fixed and
the tape guiding element 20 thereon is securely and
stably located in its operative position. In such oper-
ative position of tape guiding element 20, its height
adjusting unit 172 can be conveniently adjusted to
ensure that its axis is at a predetermined angle perpen-
dicular to the longitudinal median of the tape guided
thereby and further is parallel to the face of the tape
which extends thereto from the peripheral surface of
drum 13 by way of guide 26, heads 28 and 29 and guide
24a.
Upon completion of the tape loading operation
of unit 15, pinch roller 21 is disposed adjacent capstan
23 so that, upon energization of solenoid 202, pinch
roller pressing unit 37 is effective to urge pinch roller
20 against capstan 23 with a predetermined contact pressure
therebetween which is substantially uniform along the
axial length of the pinch roller, and therefore across
the width of the tape 4.
As earlier noted, actuation of an eject push-
button (not shown) may be effective to initiate a tape
unloading operation of the apparatus by causing motor
216 of drive unit 36 to operate in the direction for
rotating gears 211 and 212 in the directions of the arrows
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~6~ 9
S on Fig. 40. Such rotation of gear 211 causes turning
of ring 51 in the counterclockwise direction, as viewed
on Fig. 8, and connecting rod assembly 89 provides
corresponding movement of movable base 56 from guide
plate 47 along track member 44 so as to move tape guiding
elements 16 and 17 back to their original or inoperative
positions shown in broken lines at 16 and 17 on Fig. 1.
The turning of ring 51 in the counterclockwise direction
further causes tape guiding elements 18 and 19 to be
returned to their respective original positions shown
in broken lines at 18' and 19' on Fig. 1. In transmitting
the movement of ring 51 to movable base 56 during the
tape unloading operation, projections 93 on rod 90 are
engaged against ends of the respective apertures 94 of
cylinder 91 for directly transmitting the pull of rod
90 to cylinder 91. As movable base 56 moves along track
member 44 and attains the horizontal end portion 45a of
top wall 45, connécting rod assembly 89 is gradually
returned from its inclined position, at the completion
of the tape loading operation (Fig. 9), to its substan-
tially horizontal position at the completion of the tape
unloading operation (Fig. 10).
During the tape unloading operation of unit 14,
tape guiding elements 19 and 18 are successively acted
upon by guides 300 and 33 and by guide depressing plate
54 so that such guiding elements 18 and 19 are brought
down to nearly horizontal positions against the force of
the respective springs 111 and are maintained substantially
supine under plate 54.
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When the tape guiding elements 16-19 have
reached their respective original positions indicated
in broken lines at 16'-19' on Fig. 1, the unloading of
the tape by unit 14 is completed and protuberance 154
acts on lever 144 so that the completion of unloading
is detected by switch 147.
Simultaneously with the unloading operation
of unit 14, the rotation of gear 212 in the direction of
the arrow S on Fig. 40 causes movement of upper plate
159 of movable base 157 in the direction of the arrow J
on Fig. 30. During such movement of upper plate 159,
ends of slots 163 and 164 engage guide pins 161 and 162
to cause corresponding movement of lower plate 158
horizontally in the arcuate path defined by guides 160.
Thus, tape guiding element 20 and pinch roller 21 are
moved back to their original positions indicated in
broken lines at 20' and 21' on Fig. 1, and at which the
tape unloading operation of the take-up side unit 15
is also Gompleted.
Since the driving unit 36 employs a single
motor 216 for driving both loading units 14 and 15, it
will be apparent that both of the loading units 14 and
15 are advanced or returned along their respective
paths of motion, by forward or reverse rotation,
respectively, of motor 216 in complete synchronism with
each other so that the relative timing of the loading
units 14 and 15 cannot be disturbed during successive
loading and unloading operations.
~16~9
It is also to be appreciated that, upon the
completion of a loading operation, all of the tape
guiding elements 16-20 of loading units 14 and 15 are
accurately and~securely positioned so that the tape
4 is securely guided without vibration thereof during
a recording or reproducing operation to ensure the
performance of such operations with a high de~ree of
accuracy.
The fact that tape guiding elements 18 and
19 of feed side loading unit 14 are disposed nearly
horizontally under depressing plate 54 in the completely
unloaded state of the apparatus and, at the initial
portion of a tape loading operation, such guiding elements
18 and 19 pass under the tape run 4' (Fig. 1) and then
rise to engage the tape, makes itpossible to provide a
relatively small gap between the lower edge of tape run
4' in the operatively positioned cassette and the chassis
5, that is, the gap hl (Fig. 2) between the underside
ld of the operatively positioned cassette 1 and the
chassis 5 can be quite small. Further, since tape
guiding elements 18 and l9 are supine and drawn under
depressing plate 54 in the completely unloaded state of
the apparatus, only tape guiding elements 16, 17 and 20
and pinch roller 21 need to extend into the cutout 10 at
the bottom of the operatively positioned cassette 1 at
the time when the latter is moved downwardly to its
operative position. Such tape guiding elements 16, 17
and 20 and pinch roller 21 can be reliably positioned
so they do not strike against each other or come into
accidental contact with the tape during the movement of
the cassette to its operative position.
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Since the movable base 56 carrying tape guiding
elements 16 and 17 is only connected to drive ring 51 by
means of the connecting rod assembly 89, and the tape
guiding elements 18 and 19 are pivoted on ring 51 for
swinging between their supine and erected positions, ring
51 can be simply rotated in a horizontal plane, while
tape guiding elements 16 and 17 are moved along a pre-
determined inclined path which is most desirable for the
tape loading operation and for the smooth transport of
the loaded tape. Moreover, the path of movement of
tape guiding elements 16 and 17 can be selected to
minimize its maximum height h4 (Fig. 2) above chassis 5
and to maintain such he~ght approximately within the
height h3 necessary for the cassette 1 in its operative
position which includes the height h2 by which the
cassette lid 9 projects above the remainder of the
cassette in its opened position. Consequently, a VTR
having a tape loading apparatus according to this
invention may be provided with a very small height so
as to constitute a so-called thin VTR.
It will also be appreciated that the operation
of the take-up side loading unit 15 is simplified by
reason of the fact that its base 157 is merelv moved
horizontally on the chassis 5. Since the range of move-
ments of the base 57 is very small, the width Wl
(Fig. 4) of the tape loading apparatus according to this
invention can be minimized, for example, so as to be
completely within the width W2 of the cassette 1 and,
consequently, it is possible to provide a VTR whose
width is very small.
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~ 164~ a9
Finally, by reason of the previously described
arrangement and operation of the loading units 14 and 15
according to this invention, the overall dimension 11 of
the tape loading apparatus in the fore and aft direction,
and the gap 12 required between the front of the operatively
positioned cassette 1 and the guide drum 13 may be
relatively small so that it is also possible to provide
a VTR having a very small dimension in the corresponding
direction. In other words, a VTR having a tape loading
apparatus according to this invention may be made very
compact.
Although an embodiment of this invention has
been described in detail herein with reference to the
accompanying drawings, it is to be understood that the
invention is not limited to that precise embodiment, and
that various changes and modifications may be effected
therein by one skilled in the art without departing from
the scope or spirit of the invention as defined in the
appended claims.
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