Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
BACKGROUND OF THE INVENTION 1 3 2 2 4 1 3
Field of the Invention
This invention relates generally to a cassette tape
recording and/or reproducing apparatus, and more particularly to
a cassette tape recording and/or reproducing apparatus, such as a
cassette tape video recorder or the like, which is capable of
selectively loading either of a large-sized tape cassette and a
small-sized tape cassette.
Description of the Prlor Art
In cassette tape recording and/or reproducing apparatus,
such as a cassette tape video recorder (hereinafter described in
"VTR"), a pair of right and left position reference pins and a
pair of right and left height reference pins are provided on a
chassis in the apparatus, and the bottom plate of a tape cassette
loaded in the apparatus is engaged with these pins so as to put
the tape cassette in its horizontally and vertically exact
position by the former pins and in its vertically exact position
by the latter pins. And generally, the front side part of the
bottom plate near the side of an openlng for tape-loadiny is
engaged with the position reference pins, and the right and left
corners on the rear side of the bottom wall that are the opposite
side for the opening are engaged with the respective height
reference pins. :
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In the meantime, the recent VTR is often so constructed
as to be able to record on or reproduce from the tape cassette of
more than two kinds selectively loaded therein, the spaces
between a pair of right and left reels of which are different
from one another, s~lch as the large-sixed cassette and the
small-sized cassette.
In the VTR of this sort, a pair of right and left reel
bases are automatically moved so as to make the space between the
reel bases coincide with the space between the reels of the
loaded cassette, such as the large-sized cassette or the
small-sized cassette, and generally, the reel bases are moved
together with the reel motors which drive the reel bases.
~ owever, if the height xeference pins of the VTR
engaging with the corner portions on the rear side of the
small-sized cassette, are carelessly projected from the chassis,
the height reference pins are to beset the paths of the reel
basses and reel motors.
In order to overcome the above problem, provided in the
VTR of this sort is only one height reference pin engaged with
the small-siæed cassette at the center of the rear side of lts
bottom plate but the height reference pin provided like that
makes lt difficult to provide~ a guide for making the center line
with respec to the width of the smali-sized cassette colncide
: with that of the cassette holder, the guide ~eing requisite while
the:small-sized cassette is lnserted in~ a oassette holder of the
VTR o
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Furthermore, the height reference pin is generally engaged
with the corner portion of the bottom plate of the cassette for the
reason why the corner portion is rigid enough to obtain the exact
positioning of the cassette. On the contrary, the center portion
on the side of the bottom plate is not rigid enough and apt to be
deformed when the height reference pin is engaged therewith, 90 it
is difficult to obtain the exact positioning of the cassette.
Where a pair of height reference pins of the VTR engaging with
corner portions on a rear side of a small-sized cassette are
provided so as not to impede the movement of the reel bases, if the
reel of a large-sized tape cassette is very large in diameter
compared with that of the small-sized tape cassette, the large-
sized tape cassette is supported by the height reference pins at
portions near a pair of reel base insertion holes where are not
rigid enough to keep the shape, with the result that the support of
the large-sized tape cassette becomes unstable. Thus, it is
difficult to obtain the exact positioning of the large-sized tape
~assette.
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OBJECTS AND SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to
provide a tape cassette capable to be loaded in an exact position
of a cassette tape recording and/or reproducing apparatus which
selectively loads a large-sized tape cassette and a small-sized
tape cassette whose center-to~center spaces between reels differ
from each other.
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In accordance with an aspect of this invention, a tape
cassette which is the large one of at least a large-sized tape
cassette and a small-sized tape cassette, whose center-to-center
spaces between a pair of right and left reels differ from each
other and each capable of being selectively loaded in a cassette
tape recording and/or reproducing apparatus, said tape cassette
comprises a pair of right and left positioning holes provided in
the bottom face thereof and engaged with a pair of right and left
position reference pins disposed within said apparatus in order to
put itself in its horizontally and vertically exact position, and
a pair of right and left recesses provided in said bottom face in
order to prevent itself from contact with a pair of height
reference pins disposed within said apparatus to put the small-
sized tape cassette in its vertically exact position.
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BRIEF DESCRIPTION OF THE DRAWINGS.
Figure 1 is a plane view of mobile bases disposed in a
cassette tape recording and/or reproducing apparatus according to
a first embodiment of this invantion
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Figure 2 is an elevation view, partly broken away and in
s~ction, of a large-sized tape cassette mounted on the mobil
bases of Figure l;
Figure 3 is a side viewl partly broken away and in
section, of the large-sized tape cassette loaded in the cassette
tape recording and/or reproducing apparatus of Figure l;
Figure 4 is an elevation view, partly broken away and in
section, of a large-sized tape cassette mounted on mobile bases
disposed in a cassette tape recording and/or reproducing
apparatus according to a second embodiment of this invention;
Figure 5 is a side view, partly broken away and in
section, of the large si~ed tape cassette loaded in the casse~te
tape recording and/or reproducing apparatus of Figure 4; and
Figure 6 is a bottom view of the large-sized tape
cassette of Figure 5.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Refexring to the drawings in detail, a VTR capable of
selectively loading a large-sized tape cassette and a small-sized
tape cassette, embodying the present invention will be described.
Figures 1 to 3 of the drawings show the fixst embodiment
of this invention. As shown in Figures 1 and 2, a pair of right
and left mobile bases 3 are movable in directlon of arrows a and
b each along a pair of guide ralls 5 whi~h are horizontally
disposed on a chassis 4. A pair of right and left reel bases 1
and a pair of reel motors 2 or driving the reel bases 1 are
mounted on the mobile bases 3 Further, a pair of right and left
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position reference pins 8 and a pair of right and left height
reference pins 9 each used in common for positioning the
large-sized tape cassette 6 and the small-sized tape cassette 7
are secured to the chassis 4 and the pair of right and left
mobile bases 3, respectively.
When the large-sized tape cassette 6 is selectively
loaded in the VTR, the reel bases 1 and the height reference pins
9 are moved in advance in the direction of arrow a by the movile
bases 3, and the bottom plate 6a of the large-sized tape cassette
6 is made to come in contact wi~h the upper end faces 8a and 9a
of the position reference pins 8 and the height reference pins 9.
At the same time, the reel bases 1 are fitted into a pair of
right and left reel base insertion holes 10 disposed in the
bottom plate 6a, so that the spindles la projected from the reel
bases 1 are engaged with a pair of right and left reels 11 in the
cassette 6~
Also when the small-sized tape cassette 7 is loaded in
the VTR, the reel bases 1 and the heiyht reference plns 9 are
moved in advance in the direction of arrow b by the mobile bases
3, and the bottom plate o~ the small-sized cassette 7 ls made to
come in contact with the upper end faces 8a and 9a of the
position reference pins 8 and the height reference pins:9. At
the same time, the spindles la of the reel bases 1 are engaged
with a pair of r~ght and left reels in the cassette 7.
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When the upper end faces 8a of the position reference
pins 8 come in contact with the bottom plate of the cassette 6, 7,
small-sized positioning pins 8b projected from the center of the
upper end faces 8a are engaged with a pair of right and left
positioning holes 12 provided in the bottom plate of the cassette
6, 7 near the front face 6b, 7~ thereof, so that the front part
of the cassette 6, 7 is put in its horizontally and vertically
exact position.
Simllarly, when the upper end faces 9a of the height
reference pins 9 come in contact with the right and left corners
of the bottom plate near the rear face 6c, 7c of the cassette 6,
7, the rear part of the cassette 6, 7 is put in its vertically
exact position.
Thus, without regard for the large-siz~d tape cassette 6
or the small-sized tape cassette 7, the bottom face, the front
face and the plane equidistant form the right and left reels of
the cassette 6, 7 are placed in normal bottom face position Pl,
normal front face position P2 and normal equidistance plane
position P3, respectively~
As illustrated in Figure 31 the cassette 6, 7 is
selectively inserted in a:cassette holder 16 through a cassette
insertion opening 15 disposed ln the front panel 14 of the VTR.
Thereafter, the cassetteholder 16 is horizontally wi~hdrawn in
direction o~ arrow c and then vertically lowere:d~in dire~tlon of
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arrow d along three L-shaped grooves 17. Thus, the cassette 6, 7
is placed on the upper end bases 8a and 9a and pressed against
them from above by a cassette push plate 18 so as to locate the
cassette 6, 7 in its exact position.
In the meantime, when the large-sized cassette 6 is much
larger than the small-sized cassette 7 as shown in Figure 1, the
height reference pins 9 moved by the mobile hases 3 support the
large-sized cassette 6 at the bottom face near the reel base
insertion holes 10 as shown in Figures 2 and 3.
On the other hand, the reel 11 in the large-sized tape
cassette 6 is very large in diameter, around which a long magnet
tape is wound, so that the bottom face 6a near the holes 10 of
the large-sized tape cassette 6 is apt to be deformed downwards
due to the weight of two reels 11 and its low rigidity caused by
the existence of the reel base insertion holes 10.
Therefore, the large-sized tape cassette 6 supported by
the helght reference pins 9 as mentioned abave is put in a
position higher by height h than the normal bottom face position
P as shown in Figures 2 and 3, so that the exact positioning of
the large-sized cassette 6 becomes difficult~ Further, the
laxge-sized cassette 6 supported both at the front side and near
the reel base insertion holes 10 of the bottom face 6a by the
four xeference pins 8 and 9 is apt to be unstable. The larger
the cassette 6 is, the more the cassette 6 is unstable,
particularly at the side near the rear face 6C of the cassette 5.
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To overcome such problems, a pair of right and left
height reference pins 21, the space between which is large, are
projected from the chassis 4 at the rear sides of the height
reference pins 9, in other words, in relations that the position
reference pins 8 and height reference pins 21 are disposed on
opposite sides to the height reference pins 9 as indicated in
chain-dotted lines in Figure 1 to 3, and thereby, the right and
left corner portions 22 of the bottom face 6a near the rear face
6c of the large-sized cassette 6 are stably supported.
However, as the bottom face 6a of the large-sized
cassette 6 is not 50 accurate ln its flatness and the heights of
the six reference pins - two position reference pins 8 and four
height reference pins 9 and 21 - generally differ a little from
one another, so the large-si2ed cassette 6 is unstably supported
on these six reference pins 8, 9 and 21.
. It seems to overcome the above problem to make the
height reference pins 9 lower downwards when the large-siæed
cassete 6 is loaded, but it must lead to making the construction~
of the apparatus complex and the manufacture thereof much
difficult.
Now, the second embodiment of this invention will be
described on reference to Figures 4 to 6 to:overcome the problem.
In the following description, the same parts of the consturction
~as those shown in Figures 1 to 3 are denoted by the same
reference numerals to make no explanation thereof.
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As shown in Figure 6, the large- ized cassette 6
indicated in solid lines is much larger than the small-sized
cassette 7 indicated in chain-dotted lines.
The position reference pins 8 used in common for positioning the
large-sized cassette 6 and the small-sized cassette 7 are fixed
to the chassis 4. ~he height reference pins 9 for positioning
the small~sized casRette 7 are fixed to the mobile base 3, and
the height reference pins 21 for positioning the large-sized
cassette 6 are fixed to the chassis 4. The former height
reference pins 9 may be fixed to the chassis 4 lest they should
interfere with the movements of the mobile bases 3.
Provided near the reel hase insertion holes 10 in the
bottom face 6a of the large-sized cassette 6 are a pair of right
and left recesses 23, the inner diameters of which are larger
than the outer diameters of the height reference pins 9, and
these recesses 23 come just over the height reference pins 9 when
the mobile bases 3 are moved in the direction of arrow a in
Figure 1 so as to make them fit for the large-sized cassette 6.
~ Thus, the bottom base 6a of the large-sized cassette 6
does not come in contact with the height reference pins 9 for
positioning the small-sized cassette 7 owing to the recesses 23,
when the bottom base 6a comes in contact wlth the upper end faces
8a of the position referencepins 8 near the front face 6b o~ the
cassette 6 and with the upper faces 21a o~ the height reference
pins 21 at the right and left corner portlons 22 near the rear
face 6c of the cassette 6.
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That is, as the large-sized cassette 6 is supported by
not six but four reference pins position reference pins 8 and
height reference pins 21 - and that at the corner portions 22 of
the bottom face 6a near the rear face 6c thereof, the stability
of the cassette 6 is much improved, and further, the bottom face
6a thereof is exactly put in the normal bottom face position Pl.
And the same may be said of the small-sized cassette 7, because
the cassette 7 is supported only by the position reference pins 8
and helght reference pins 9 in the same manner as mentioned in
the first embodiment.
Having described illustrative embodiment of this
invention with reference to the accompanying dxawings, it is to
be understood that the invention is not limited to those precise
embodiments, 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.
And this invention can be applied not only to the VTR
but also to the various kinds of cassette tape recorder and data
processing device.
The apparatus of this invention has the pair of position
reference pins 8 used in common for the large-sized tape cassetté
6 and the small-sized tape cassette 7,: and two pairs of height
reference pins - the pins 21 used for the large-sized tape
cassette 6 and the pins 9 used for the small-sized tape cassette
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7. Therefore, whether the cassette 6, 7 is large or small, the
front portion of the cassette 6, 7 selectively loaded in the
apparatus is put in its accurate horizontal and vertical position
by the help of the position reference pins 8 which support the
right and left portions near the front face 6b, 7b of the
cassette 6, 7 and the rear portion of the cassette 6, 7 is put in
an accurate vertical positlon by the help of the respective
height reference pins 9, 21 whlch support the right and le~t
corner portions 22 near the rear face 6c, 7c of the cassette 6,
7, so that the bottom face 6a, the front face 6b, 7b and the
central plane equidistant from the pair of reels 11 of the
cassette 6, 7 are exactly put in the respective predetermined
normal face or plane positions Pl, P2 and P3.Particularly, in
case of the second embodiment, the large-sized cassette 6 loaded
in the apparatus is made to be out o~ contact with the height
reference pins 9 for positloning the small-sized cassette 7, only
with the pair of recesses 23 simply disposed near the reel base
insertion holes 10 thereof. In other words, it is unnecessary to
adopt such a very complex
constructin as to lower the pair of height reference pins 9 when
the large-sized tape cassette 6 is loaded, so as to prevent the
large-sized cassette 6 from oontact with the pair of helght
reference pins 9. Further, the large-sized tape cas-~ette 6 is
positioned with much accuracy without beiny lnfluenced by the
defonmatlon of the bottom face 6a near the~reel base insertion
holes 10 thereof, so that the accuracy of recording and
reproducing of the large-sized cassette 6 is much improved.
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