Note: Descriptions are shown in the official language in which they were submitted.
1;~89584
MEDIA RECEIVING UNIT
BACKGROUND OF THE INVENTION
This application is a division of copending Canadian Patent
Application Serial No. 507,388 Filed April 23, 1986.
1. Field of the Invention
The present invention relates to a media receiving
unit for receiving printed media (sheets of paper) discharged
from a printer, a copying machine, etc.
2. Description of the Related Art
Generally, recorded media (printed papers)
discharged from a printing machine such as a printer and a
copying machine are accumulated with the printing thereon
facing upward in a receiver of a media receiving unit disposed
under the printing machine.
This method is advantageous when monitoring whether
or not the printing conditions of the papers are proper, but
is disadvantageous in the papers which have been printed
sequentially are piled up in a reversed sequence in the
receiver.
To overcome this disadvantage, some prior art
mechanisms have been proposed by which the sequence of papers
discharged from the printing machine is reversed. These prior
art mechanisms, however, cannot effect this reversal of the
paper at a low cost. Therefore, there is still required the
provision of a compact mechanism which will properly effect
the reversal of papers at a low cost.
SUMMARY OF THE INVENTION
It is feature of an embodiment of the present
invention to provide a media receiving unit which is compact
and can properly reverse the printed media (papers) received
from a printer, copying machine, etc.
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In accordance with an embodiment of the present
invention there is provided a media receiving unit comprising:
a media reception means for receiving sequentially one upon
another a plurality of sheet media which are discharged from
discharging means of a media processing apparatus at a
discharge speed VO, the media reception means comprising a
mechanism for reversing the media and electrical driving means
for driving the media reversing mechanism means for
detachably mounting the media reception means to the media
processing apparatus; and a connector for supplying electrical
power from the electrical driving means to the media
processing apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
Features of the present invention will become apparent
from the following description with reference to the
accompanying drawings, in which:
Fig. 1 is a cross-sectional view showing an embodiment;
Fig. 2 is a front view showing the embodiment shown in
Fig. l;
Fig. 3 is a view for explaining the operation of the
present invention;
Fig. 4 is a view showing the constitution of the
embodiment;
Fig. 5 is a side view showing an essential part of
another embodiment;
Figs. 6 are views showing the overall constitution of the
embodiment shown in Fig. 5, wherein Fig. 6(A) is a front view,
Fig. 6(B) a plan view, and Fig. 6(C) a side view;
Fig. 7 is a block diagram showing the embodiment shown in
Figs. 6;
Fig. 8 is a perspective view showing still another
embodiment;
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Fig. 9 is a view showing dimensions of the embodiment
shown in Fig. 8;
Fig. 10 is a view showing the constitution of still
another embodiment;
Fig. 11 is a circuit diagram showing the embodiment shown
in Fig. 10;
Fig. 12 is a view for explaining the operation of the
circuit shown in Fig. 11;
Fig. 13 is a view showing the constitution of still
another embodiment;
Fig. 14 is a perspective view showing still another
embodiment;
Fig. 15 is an exploded perspective view showing the
embodiment shown in Fig. 14;
Fig. 16tA) and (B) are views for explaining the operation
of the embodiment shown in Fig. 14;
Fig. 17 is a view showing the constitution of still
another embodiment;
Fig. 18 is a time chart showing the embodiment shown in
Fig. 17;
Fig. 19 is a circuit diagram showing the embodiment shown
in Fig. 17; and
Fig. 20 (A), (B), (C), and (D) are views for explaining
prior arts.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before describing the preferred embodiments of the
present invention, an explanation will be given of the prior
art for reference purposes.
Figure 20 (A) shows a printer 1 to which the present
invention is applicable. In the printer 1, papers 4 are set
in a paper cassette 2, picked up one by one by a pick roller
3, and sent by a feed roller 5 to a photo-sensitive drum 7,
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where an image on the drum 7 is transferred to the paper 4 by
a transferring device 6. The image on the paper 4 is then
fixed by a fixing device 8, and the paper 4 is discharged
outside the printer 1 by a discharge roller 9.
Figure 20(A) shows an example of a prior art mechanism
for reversing papers. In this example, a wheel 12 having
rubber fins 13 is rotated by a motor (not shown). The rubber
fins 13 touch a reverse side (opposite side of a printed side)
of the paper 4 to turn the paper 4 over and place it in a
stacker 11.
Figure 20(B) shows another prior art mechanism for
reversing papers. A tray 14 for receiving papers is provided
under a printer 1. A paper 4 is fed by feed rollers 15 along
reversing guides 16 and 17 which turn the paper 4 over and
send it into the tray 14 in which the paper 4 is piled.
Figure 20(C) shows still another prior art mechanism for
reversing papers. A switchback means 19 comprising feed
rollers 20 which are reversibly driven turns a paper 4 over to
pile the paper 4 in a stacker 18.
Figure 20(D) shows still another prior art mechanism for
reversing papers and receiving the papers in a media receiver
21, in which a collecting wheel 22 comprising linear nails 23
fitted to a rotary shaft 24 is used. The collecting wheel 22
is disposed in the middle of a paper guide 25. A paper 4
discharged from a discharge roller 9 is received by one of the
nails 23, and the discharge force of the paper 4 causes the
collecting wheel 22 to turn. The paper 4 then abuts against a
stopper 26 of the media receiver 21, and is received in the
media receiver 21 in a reversed state.
The prior art reversing mechanism shown in Fig. 20(A),
which makes use of gravity, needs a large installation space
because the media receiver 11 must be arranged below the
discharge roller 9. Further, the mechanism has a drawback in
that the reversing operation by gravity may not be surely
performed, accurately if the paper 4 is curled.
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performed, accurately if the paper 4 is curled.
The prior art reversing mechanism shown in Fig. 20(B) is
disadvantageous in that the mechanism is bulky, because it
requires a number of components such as the rollers 15 and
guides 16 and 17.
In the prior art reversing mechanism shown in Fig. 20(C),
a second paper is fed only after the completion of feeding of
a first paper so that the timing of paper discharge is limited
and process is slow.
If the paper 4 is curled in the prior art reversing
mechanism shown in Fig. 20(D), the discharge force of the
paper 4 is weakened and the collecting wheel 22 is not turned
by this force. Further, if the size of the paper 4 is large,
the rear end of paper 4 is not released from the discharge
roller 9 when the paper leading end abuts against the
stoppers, therefore the paper 4 is not received in the media
receiver 21.
The present invention has been developed in order to
overcome the above drawbacks of the prior art and provides a
media receiving unit provided with a rotary drum which is
disposed in front of a media discharge port of a printing
machine and equipped with flexible sheets, in which a paper is
reversed by the resiliency of the flexible sheets.
Figure 1 is a cross-sectional view and Fig. 2 is a front
view of an embodiment of the present invention. Figure 3 is a
view for explaining the operation of the embodiment. A rotary
drum 27 is connected with a step motor M through a shaft 33.
The step motor M is fixed to one side of a recording apparatus
1 and driven in response to a rotation control signal sent
from a controlling portion (not shown).
A paper 4 is discharged with a feeding speed of VO from a
discharge roller 9 arranged in the recording apparatus 1. The
rotary drum 27 shown in Fig. 1 is in a standby state waiting
for the paper 4 to be discharged, and at this position,
flexible sheets 28-1 and 28-2 made of polyester film and fixed
to the rotary drum 27 are opened by an angle 8 to receive the
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paper 4 therebetween. The flexible sheets 28-1 and 28-2 are
fixed to rotary drum 27 by screws 30 through a fitting 29.
A separation stopper 32 is disposed under the rotary drum
27 in such a manner that the stopper 32 extends on both sides
and beyond the circumference of the rotary drum 27 toward a
shaft 33. The paper 4 is stopped by the stopper 32 and
dropped in a stacker 31. The recording apparatus 1 is
provided with a motor 34 for rotating the discharge roller 9.
A encoder E for detecting the standby position of the rotary
drum 27 is fixed to the shaft 33. A detection hole which
emits a signal detected by a photosensor F is formed on the
encoder E to detect a standby state.
The paper 4 discharged from the discharge roller 9 is
reversed as shown in Figs. 3(A) to (D) and described later.
Usually, a sensor is disposed between a fixing device of the
recording apparatus 1 and the discharge roller 9 to detect the
passage of a paper. According to a detection signal of the
sensor, the rotary drum 27 is rotated after maintaining a
standby state for a predetermined period of time.
The length of upper flexible sheet 28-1 may by made
shorter than that of the lower flexible sheet 28-2 to ensure
that the paper 4 slips easily between them. In this
embodiment, the length of the flexible sheet 28-1 is 50 mm to
100 mm.
The rotary drum 27 is rotated at a circumferential speed
of about 0.8Vo which is slower than the discharge speed VO of
paper 4. As a result, the paper 4 is fed between the flexible
sheets 28-1 and 28-2 and bent as shown in Fig. 3(B), and the
spring force of flexible sheet 28-2 then reverses the paper 4.
To this end, the length of the lower flexible sheet 29-2 is
made 150 mm or more to reverse the paper 4 by the resiliency
of the flexible sheet 28-2 irrespective of the unstable nature
of the paper 4.
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The sequence of reversal of the paper 4, which is
discharged from the recording apparatus 1 by the discharge
roller 9 and reversed and received by the media receiving
unit, will now be described with reference to Figs. 3(A) to
(D).
Figure 3(A) shows a state wherein the paper 4 has just
been discharged from the discharge roller 9. The rotary drum
27 is in a standby (stop) state just before starting to
rotate. This state is set by stopping the motor M according
to a detection signal from a position sensor (not shown) which
detects the position of the rotary drum 27. The flexible
sheets 28-1 and 28-2 are arranged in such a manner that the
paper 4 is easily introduced therebetween.
Figure 3(B) shows a state in which the paper 4 has been
inserted between the flexible sheets 28-1 and 28-2, and the
rotary drum 27 has started to rotate.
The revolutional speed of the rotary drum 27 is about 0.8
V, which is slower than the discharge speed VO of the paper 4
discharged from the discharge roller 9. Accordingly, as
shown, in Fig. 3(B), the paper 4 is bent between the discharge
roller 9 and the rotary drum 27. During this situation, the
flexible sheet 28-2 is forced to bent convexly backward by the
paper 4.
Then, as shown in Fig. 3(C), the rear end of the paper 4
is flipped by the elastic restoring force of the flexible
sheet 28-2 in accordance with the rotation of the drum 27.
Then, the paper 4 is reversed as shown in Fig. 3(D). The
longer the length of flexible sheet 28-2, the better the
reversal of the paper 4 caused by the resiliency of the
flexible sheet 28-2, irrespective of the unstable nature of
paper 4. The front end of the paper 4 then abuts against the
stopper 32 and is released from the flexible sheets 28-1 and
28-2 and received in the stacker 31.
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Figure 4 is a perspective view showing another embodiment
according to the present invention, in which a paper 4 fed
between the flexible sheets 28-1 and 28-2 are securely held
and completely reversed.
In Fig. 4, one end of the flexible sheets (films) 28-2 is
fitted to a rotary drum 27'. A bar 35 is disposed in such a
manner that the bar 35 can move radially relative to and in
the vicinity of the periphery of rotary drum 27'. Projections
a of the bar 35 engage with grooves b formed on the rotary
drum 27'. Springs 36 are provided on both sides of the rotary
drum 27' to press the bar 35 against the rotary drum 27'. The
other flexible sheets 28-1 are fixed to an inner side of the
bar 35 in such a manner that one end of the flexible sheets
28-1 is in contact with the flexible sheets 28-2. The
flexible sheets 28-1 may be fixed to the rotary drum 27'
instead of the bar 35.
Shafts 33 extending outwardly from both sides of the
rotary drum 27' are rotatably supported by side plates d, and
cams 37 are fixed to the side plates d. The cams 37 push the
bar 35 upward when the flexible sheets 28-1 and 28-2 are
located at upper positions to easily receive the paper 4
between the flexible sheets 28-1 and 28-2. According to the
rotation of the rotary drum 27', the bar 35 is lowered due to
the action of cams 37 and securely holds the paper 4. When
the rotary drum 27' rotates further, the paper 4 is reversed,
and the bar 35 is pushed upward by the cam 37. The paper 4 is
then released from the bar 35. Separation stoppers 32 are
disposed to separate and release the paper 4 into a stacker 31
located below the rotary drum 27'. Recessed c are formed on
the bar 35 to avoid interference of the bar 35 with the
stoppers 32.
Figure 5 shows an arrangement of still another embodiment
according to the present invention. Pairs of flexible sheets
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128-1 and 128-2, and 128'-1 and 128'-2 are fixed at
diametrically opposed positions on a rotary drum 127. The
front ends of each pair of flexible sheets are aligned with
each other, and a presser bar 135 corresponding to the bar 35
shown in Fig. 4 is provided at each of these front ends. A
discharge roller 109 is arranged in a printer (not shown) to
discharge a printed paper 104 in a direction indicated by an
arrow Y. The rotary drum 127 is driven by a motor Ml for
rotation in a direction indicated by an arrow Z. A bar member
150 for detecting a rotational position of the rotary drum 127
is fixed to the rotary drum 127. As in the previous
embodiment, the paper 104 is held between one of the pairs of
flexible sheets, reversed, and then received in a stacker 131.
The stacker 131 can be reciprocated along an axis of rotation
(perpendicular to the plane of Fig. 5) of the rotary drum 127
by a motor M2 for offset driving. Thus, the stacker 131 can
be moved to sort the printed papers according to the document.
A photosensor Sl for detecting papers is disposed
adjacent to the discharge roller 109 of the printer, and a
photosensor S2 is used to detect whether or not the stacker
131 is full of paper. A microswitch S3 for detecting a home
position detects that one (in this case, 128-1 and 128-2) of
the pairs of flexible sheets 128-1 and 128-2, and 128'-1 and
128'-2 of the rotary drum 127 has reached a position
(indicated by a continuous line) at which it can for receive
the paper 104; microswitch S4 for detecting a standby position
detects that one of the pairs of flexible sheets has reached a
position (indicated by a dash line) which is thirty degrees
before the home position; switch S5 detects a normal position
of the stacker 131; and a switch S6 detects an offset position
of the stacker 131.
The operation of the embodiment shown in Fig. 5 will now
be described. The rotary drum 127 is in an optional position
before it is energized. When the motor Ml is driven, the drum
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127 is rotated in a direction indicated by the arrow Z and
stopped at the home position if the bar member 150 reaches the
switch S3. The stacker 131 is set to the normal position
according to the drive of motor M2. When the printed paper
104 is transported, the sensor Sl detects a passage of the
front end of the paper 104. After the detection of the front
end of the paper 104, and after the elapse of time during
which the front end of paper 104 reaches a chuck portion (a
position where the presser bar 135 is located) of the flexible
sheets in the home position, the motor Ml starts to rotate.
The timinq of the drive of motor Ml is calculated in advance
according to a distance between the sensor Sl and the chuck
portion of flexible sheets and a discharge speed of a paper.
On this occasion, the rotation speed of the drum 127 is set to
be slower than the discharge speed of a paper 104 caused by
the discharge roller 109.
If the paper 104 is long, the rotary drum 127 is rotated
by 150 tG reach the standby position indicated by a dash line
before the sensor Sl detects and rear end of the paper 104,
and the sensor S4 detects that the standby position is
attained and stops the rotation of motor M1. At this standby
position, the rear end of paper 104 is continuously discharged
from the discharge roller 109 while the front end of paper 104
is held and stopped. After the detection of the rear end of
paper 104 by the sensor Sl and after the elapse of time during
which the rear end of the paper 104 travels from the sensor S
to the discharge roller 109, namely, when the paper 104 is
released from the discharge roller 109, the motor Ml is again
driven to flip the rear end portion of the paper 104 by the
resiliency of lower flexible sheet 128-2 while holding the
front end of the paper 104 to reverse the paper 104. In this
occasion, the motor Ml is driven faster than a normal speed.
The presser bar 135 is then released by the cam means
described before, and the front end of the paper 104 abuts
against stoppers in the same manner as in the previous
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embodiment and is separated from the flexible sheets 128-1 and
128-2 to drop in the stacker 131. The other pair of flexible
sheets 128'-1 and 128'-2 then comes to the home position that
is detected by the sensor S3 to stop the rotation of motor M
until the next paper is discharged.
If the paper 104 is short, the sensor Sl detects the rear
end of paper 104 before the sensor S4 detects that the drum
127 reaches the standby position. Namely, that before the drum
127 is rotated by 150, the rear end of paper 104 is
discharged from the discharge roller 109. In this case,
similar to the previous case the motor Ml is rotated with an
accelerated speed after the detection of the rear end of paper
104 by the sensor Sl and after the elapse of time during which
the rear end of paper 104 travels from the sensor Sl to the
discharge roller 109. In this case, however, the motor Ml is
not stopped at the standby position but continuously rotated
until the other pair of flexible sheets comes to the home
position.
When a stacker offset instruction is generated to sort
printed papers for each document unit and pile them in the
stacker 131, the stacker 131 is moved by the motor M2. The
sensors S5 and S6 detect a position of the stacker 131 to be
moved and stop the motor M2 at a predetermined position. This
document collating operation will be described later. If the
photosensor S2 comprising a light emitting element and
photosensitive element detects that the stacker 131 is full of
papers, a print termination signal is generated, and the
printing operation and the reversing operation are stopped
after the paper being discharged from the discharge roller 109
is reversed and received in the stacker 131.
Figure 6 are overall views of the reversing mechanism
having the constitution mentioned above, in which Fig. 6(A) is
a front view, Fig 6(B) a plan view, and Fig. 6(C) a side view.
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Two pairs of flexible sheet pairs 128 and 128' are provided at
each of three locations along the rotary drum 127. The sheet
pairs 128 and 128' comprise upper short flexible sheets 128-1
and 128'-1 respectively, and lower long flexible sheets 128-2
and 128'-2 respectively. With respect to flexible sheet pairs
128 and 128', two presser bars 135 are oppositely provided on
the periphery of and along the drum 127. Both ends of each
presser bar 135 are pulled by springs 136 toward a shaft 133
of the drum 127, and the shaft 133 is supported by frames 153.
Cams 137 similar to the cams shown in Fig. 4 are fixed to the
frames 153, and cam followers 154 provided at ends of the
presser bars 135 slide on the cams 137. The rotary drum 127
is driven by a motor Ml which is connected to the shaft 133
through a reduction gear 152 and a belt 151. Annular grooves
150 are formed on the rotary drum 127 between the positions at
which the flexible sheets are fitted. Separation stoppers
(not shown) similar to those shown in the previous embodiment
are disposed in the annular grooves.
The shapes of the flexible sheets in the home position
are shown in Fig. 6(C). As shown in the figure, the lower
long flexible sheet 128-2 is bent along the rotary drum 127
and does not project outward, so that a space for arranging
the flexible sheets does not need to be increased even if the
length of each flexible sheet is elongated. The numeral 155
represents a paper guide frame. The side frame 153 has a bent
lever 156 which is provided with a shaft 162 to attach the
reversing mechanism to a printer. The lever 156 is pulled
upward by a spring 159 and keeps a horizontal position due to
a stopper (not shown). A tapered face 157 is formed at the
front end of the bent lever 156, and recess 158 is formed on a
back side of the tapered face 157. Rollers 160 slide on a
guide rail (not shown) of the printer. A connector 161 is
provided under the paper guide frame 155. The connector 161
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is for connecting power lines, signal lines, etc., of the
reversing mechanism with the printer. The media receiving unit
including such a reversing mechanism is constructed solidly as
a single unit and fitted to the printer. To attach the media
receiving unit to the printer, the media receiving unit is
engaged in a direction indicated by an arrow X shown in Fig.
6(C) with the printer. At this moment, the rollers 160 slide
on the guide rail (not shown) of the printer, and the tapered
face 157 of the bent lever 156 abuts against a pin (not shown)
fixed to the printer. The bent lever 156 is then pushed
downward by the pin, and the pin enters the recess 158 to be
locked therein. In order to release the lock, an end 163 of
the lever 156 is pulled to lower the recess 158. The
connector 161 is aligned with a connector (not shown) of the
printer in advance so that they may be coupled together
according to the above attaching process.
Figure 7 shows a circuit diagram for controlling the
reversing operation mentioned above. The numeral 1 represents
the printer, and 100 the reversing mechanism. A circuit 101
for controlling the operation of printer 1 is connected with a
microprocessor unit (MPU) 102 for controlling the reversing
operation. The numerals 103, 104, and 105 represent driving
circuits, and 106 a receiver circuit. The MPU 102
incorporates RAMs, ROMs, I/O ports, timers, etc., and controls
the operation of the motor Ml and M2 according to printing
signals and signals from the sensors Sl to S6 to reverse the
printed papers and control the movement of a stacker.
Figure 8 is a perspective view showing still another
embodiment according to the present invention. In this
embodiment, the stacker 231 has a modified shape. A
projection 200 is formed on the stacker 231 and is located in
such a manner that it will be positioned within a front half
of a paper 204 which is reversed and received in the stacker
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231. Due to the projection 200, a rear end of the paper 204,
particularly when the paper 204 is long, will not be folder
toward a front end thereof after the paper 204 is reversed.
The paper 204 is flipped backward by an inertial force of the
reversing action and dropped along a slanted surface on a back
side of the projection 200 so that the reversing and receiving
operations of the paper 204 will be securely carried out. If
an edge of the paper 204 will be securely carried out. If an
edge of the paper 204 is aligned with a reference edge, which
will be one side edge (a right side edge in the embodiment
shown in Fig. 8) of a discharge port of a printer, the
projection 200 may be formed in a ridge like shape which does
not run in parallel with a rotation shaft 233 of a rotary drum
227 for reversing a paper. This shape of the projection 200
realizes a correct reversing operation with respect to
particularly a large size paper.
If the size of a paper is "B4", the dimensions of stacker
shown in Fig. 9 are suitable. In Fig. 9, the numeral 214
represents a separation stopper, 202 a printer, and 209 a
discharge roller. Dimensions in the figure are in
millimeters.
Figure 10 is a view showing another constitution of a
stacker-full detection sensor in the media receiving unit
according to the present invention. A motor Ml for driving a
rotary drum 327 is provided with an encoder 350 for
controlling the operation of a motor Ml. The encoder 350 has
a plurality of through holes (not shown) arranged
concentrically, and a photosensor S2 comprising a light
emitting element 351 and a photosensitive element 352 is
disposed corresponding to the positions of the through holes.
Since the flexible sheets 328 provided on the rotary drum 327
slide on the top of the paper 304 stacked in a stacker 331,
resistance to the rotation the drum 327 will be increased to
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decrease the rotating speed thereof if the number of paper is
increased to heighten the overall height of the papers. As a
result, the rotating speed of the encoder 350 is decreased to
decrease the number of through holes (the number of pulses)
counted by the sensor S2 for a predetermined period of time.
If the counted number is zero, this signifies that the unit is
in a jammed state.
Figure 11 shows a detection circuit of the embodiment
shown in Fig. 10. Figure 12 is a time chart showing a normal
rotation state, a stack full state, and a jammed state in the
circuit shown in Fig. 11. The sensor S2 and a reference pulse
generating circuit 410 are connected to a counter 413 via an
AND circuit 412. A reset circuit 411 is also connected to the
counter 413. The marks (a), (e), and (h) shown in Fig. 12
represent pulse detection signals generated by the encoder and
the sensor S2. The signal (a) indicated the normal rotation
state, (e) the stack full state, and (h) the jammed state.
The marks (b), (f) and (i) represent reference pulses, and the
marks (c), (g), (j) represent the counter outputs
corresponding to the above three states respectively. In this
example, the counter output (c) of count number N=6 indicates
the normal rotation. In the output (g), the count number N
decreases gradually, and in the counter output (j), the count
number is N=0 due to jamming. The mark (d) represents reset
pulses which are inverted signals of the reference pulses.
Figure 13 shows an engaging state of connectors where the
media receiving unit according to the present invention is
unitized in one body and attached to a printer. A connector
501 is fixed to a frame 500 of the media receiving unit. The
media receiving unit is fitted to a printer 502 in a direction
indicated by an arrow P, and, at the same time, the connector
501 is coupled with a connector 503 provided on the printer
502. The numeral 504 represents a stacker, 505 a rotary
drum, and 506 a discharge roller.
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Figure 14 shows still another embodiment according to the
present invention. In this embodiment, printed papers are
sorted for ever document and accumulated in a tray (stacker).
As shown in Fig. 14, a tray 600 is movable in directions
indicated by an arrow Q in parallel with a rotation shaft 602
of a rotary drum 601 so that printed paper 603 to be
discharged will be piled up in the tray 600 at predetermined
positions.
Figure 15 shows the constitution of a tray ~oving
mechanism. Under the tray 600 of the reversing mechanism, a
support base 625 and a back plate 626 are assembled in one
body, and a guide pin 627 and a rack 628 are provided on the
back side of tray 600. If the tray 600 is made of resin, the
guide pin 627 and the rack 628 may be formed integrally
therewith. On the support base 625, a rail 629 for sliding
the tray 600 and holes 630 and 631 for horizontal positioning
are provided. A gap between the width of rack 628 and the
width of hole 630 is 0.2 to 0.5 mm. The back plate 626 is
attached to the reverse side of support base 625, and a
connector 620 fitted to the back plate 626 engages with a
connector on the printer side. The connector 620 is connected
to a control circuit 632, which cause a motor M2 633 to move
the tray 600 by the engagement between a pinion 634 and the
rack 628. The numerals 635 and 636 represent fitting screws.
Figures 16(A) and (B) describe the reciprocating movement
of tray 600. In the figures, a paper 603 discharged from a
discharge port 613 of a recording apparatus 612 is reversed by
a rotary drum 601 of the reversing mechanism, and is piled up
in the tray 600. Whenever a document is changed, the motor
633 is driven according to a signal from the apparatus 612 to
move the tray 600 so that the papers will be sorted for each
document and piled up in the tray 600. The movement of tray
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600 is detected by limit switches S5 and S6 similar to the
sensors S5 and S6 described in the embodiment shown in Fig. 5.
Figure 17 shows still another embodiment according to the
present invention. As shown in Fig. 17, a media receiving
mechanism of the embodiment comprises a photosensor DS for
detecting a medium 701 discharged from a discharge roller 702
of a printer 710; a cam 706 fitted to a rotation shaft 707 of
a drum 703; and a pair of cam switches SWl and SW2 which are
turned ON and OFF by the cam 706. A standby position T is set
in front of (i.e., in the figure, on the left side of) a
stopper 705 for separating discharged papers. At the position
T, the modes of operation of the drum 703 and chuck 704 are
decided after a front end of the medium 701 reaches a point
just before the stopper 705.
If the medium 701 is not detected by the photosensor DS
when the front end of medium 701 is just before the stopper
705, namely, if the medium 701 has been completely discharged,
the drum 703 continues to rotate irrespective of the standby
position T, and the chuck 704 releases the medium 701. On the
other hand, if the medium 701 is detected by the photosensor
DS, namely, if the medium 701 is not yet completely
discharged, the drum 703 is stopped temporarily at the standby
position T, and the chuck 704 continues to hold the medium 701
until the medium 701 is completely discharged.
In the latter case, the front end of medium 701 is kept
at the point just before the stopper 705 until the rear end of
medium 701 is discharged, and once the discharge is completed,
the front end of medium 701 is released so that a misreversal
can not occur.
The operation of the above embodiment will be described
with reference to Fig. 18 which is an operation timing chart,
and Fig. 19 which shows an example of a circuit of the
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embodiment. Marks used in the following description
correspond to the mark shown in Figs. 17 to 19.
(1) The photosensor DS detects a passage of the front
end of medium 701 at the time tl. At the timing t2 after the
elapse of time t after the time tl, a delay circuit 750
outputs a chuck driving signal CDS and a motor driving signal
MDS. According to the signals, the medium 701 is held, and
the drum 7Q3 starts to rotate.
(2) In the case of a short medium I, the light shielded
by the medium I is released at the timing t3 to cause the
output of photosensor DS to become 0 (low). Under these
conditions, even if the drum 703 is rotated to close the cam
switch SW2, the rotation of motor M is not stopped but
continued up to the timing t5 when the cam switch SWl is
closed.
(3) In the case of a long medium II, the inverted output
of sensor DS is 1 (high) because the light is shielded by the
medium II when the output of the cam switch SW2 becomes 1
(high) at the timing t4. As a result, a motor stopping signal
MSS is output through an AND gate and OR gate to temporarily
stop the motor.
(4) Under these conditions, only the medium 701 is
advanced. When the sensor DS detects a passage of the rear
end of the medium 701 at the timing t6, the motor stopping
signal MSS becomes 0 (low) to restart the motor M. The motor M
is rotated up to the timing t7 when the switch SWl is turned
ON. At the timing t7, the chuck 704 is released
simultaneously to complete the reversing operation of the
medium 701.
