U.S. patent number 3,919,972 [Application Number 05/256,125] was granted by the patent office on 1975-11-18 for automatic cut sheet feeding unit.
This patent grant is currently assigned to Canon Kabushiki Kaisha. Invention is credited to Hiroyuki Hattori, Toshihide Iida, Shigehiro Komori, Koichi Miyamoto, Hisashi Sakamaki, Kazumi Umezawa.
United States Patent |
3,919,972 |
Komori , et al. |
November 18, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
Automatic cut sheet feeding unit
Abstract
An automatic cut sheet feeding device provided with a cut sheet
box with an open top. The box is provided with a separation pawl
facing the inside and located on each end of the upper side of the
sheet feeding lateral side, the separation pawls being mounted to
allow the box to move vertically to some degree. The bottom surface
of the box body is inserted into the space between the lower side
and the bottom surface of the arm in order to limit the separation
pawls from moving over a certain degree. By said arrangement, the
device can feed the cut sheets effectively into the copying device
automatically, without requiring an additional guide etc., even
when the number of sheets has been reduced.
Inventors: |
Komori; Shigehiro (Yokohama,
JA), Sakamaki; Hisashi (Yokohama, JA),
Hattori; Hiroyuki (Mitaka, JA), Iida; Toshihide
(Tokyo, JA), Miyamoto; Koichi (Tokyo, JA),
Umezawa; Kazumi (Yokohama, JA) |
Assignee: |
Canon Kabushiki Kaisha (Tokyo,
JA)
|
Family
ID: |
26379883 |
Appl.
No.: |
05/256,125 |
Filed: |
May 23, 1972 |
Foreign Application Priority Data
|
|
|
|
|
Jun 4, 1971 [JA] |
|
|
46-46702 |
Jun 8, 1971 [JA] |
|
|
46-40415 |
|
Current U.S.
Class: |
271/118; 271/160;
271/169; 271/127; 271/162; 271/170 |
Current CPC
Class: |
G03B
27/586 (20130101); G03G 15/6502 (20130101); G03G
15/6517 (20130101); B65H 1/12 (20130101) |
Current International
Class: |
B65H
1/12 (20060101); G03G 15/00 (20060101); G03B
27/58 (20060101); B65H 001/12 (); B65H
003/56 () |
Field of
Search: |
;271/39,61,62R,86,118,126,127,145,147,162,160,171,170,169
;206/57R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Blunk; Evon C.
Assistant Examiner: Stoner, Jr.; Bruce H.
Attorney, Agent or Firm: Fitzpatrick, Cella, Harper &
Scinto
Claims
We claim:
1. An automatic cut sheet feeding unit comprising in
combination,
a box type body, said box type body comprising
a separation pawl on top of each forward corner section thereof,
the separation pawl being movable between a fixed upper and
variable lower positions relative to the box type body,
an intermediate plate which carries a stack of cut sheets and is
accommodated in the box type body,
spring means between the box type body and the intermediate plate
and used to press the cut sheets loaded on the intermediate plate
against the bottom face of the separation pawls in the fixed upper
position,
a feed roller mounted to be movable between a position out of
contact with the stack, in which position the spring means urges
the stack against the pawl and forces the pawl to its fixed upper
position and a feeding position in pressure contact with the stack
and below the upper fixed position of the pawl so that the pawl
rests against the stack by its own weight,
said feed roller, on receiving a feed signal, feeding the cut
sheets loaded on the intermediate plate,
and means to drive and control the feed roller.
2. An automatic cut sheet feeding unit as set forth in claim 1,
wherein the spring means is installed at the end of the paper
feeding side between the intermediate plate and the box type
body.
3. An automatic cut sheet feeding unit as set forth in claim 1,
wherein the spring means is installed in between the box type body
and the intermediate plate to push up the intermediate plate
horizontally.
4. An automatic cut sheet feeding unit as set forth in claim 1,
wherein the box type body possesses a fixed lid and movable lid
and, means mounting said box type body and its movable lid on a
copying device for said movable lid to serve as a tray for the
copied paper.
5. An automatic cut sheet feeding unit as set forth in claim 1,
wherein the box type body so composed as to be provided with a side
presser on each lateral side when facing the paper feeding
direction and a spring used to place the side pressers in positions
spaced by a distance narrower than the width of the cut sheet, and
the side pressers have a slope at the upper section thereof so as
to allow the cut sheets to be inserted and loaded
automatically.
6. An automatic cut sheet feeding unit comprising in
combination:
a box type body,
a separation pawl adjacent each forward corner section thereof and
free to move substantially, vertically relative to said box type
body,
an intermediate plate accommodated in the box type body for
carrying cut sheets thereon, said separation pawls bearing against
the upper surface of the cut sheets with a constant pressure,
resilient means operative against said intermediate plate to urge
said plate in a direction to press the uppermost of the cut sheets
loaded on the intermediate plate towards a discharge position,
a feed roller mounted above the cut sheets to cooperate with said
resilient means to exert a pressure upon the upper surface of the
cut sheets at the discharge position,
said feed roller operative upon receiving a feed signal, to feed
the uppermost cut sheet loaded on the intermediate plate, and
means to drive and control said feed roller.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an automatic cut sheet feeding unit used
in electrophotographic or various other copying devices or in
simple printers. This invention includes, further, the improvement
of cassette means used in the automatic cut sheet feeding
device.
2. Description of the Prior Art
The transfer paper for transfer type copying devices, and the
photosensitive paper used in electrofax systems, as well as the
printing paper used in simple printers are considered as cut
sheets. Heretofore, it was common practice to automatically feed
such sheets by positioning them in a cassette and then loading the
cassette in the unit. In some cases, a cut sheet box which
corresponds to the cassette was permanently mounted on this
unit.
An object of this invention is to provide a mechanism to dispense
paper, one sheet at a time, assuredly and smoothly from such a cut
sheet box.
This invention is directed to a device which automatically feeds
the above-mentioned cut sheets effectively into a copying device
etc. and does not require an auxiliary guide etc. even when the
number of sheets has been reduced. The device feeds the sheet
extremely smoothly at all times, and allows the cut sheets and
cassette to be easily loaded.
SUMMARY OF THE INVENTION
In order to attain the above-mentioned object, a cut sheet box with
an open top is provided with a separation pawl facing the inside
and located on each end of the upper side of the sheet feeding
lateral side. The separation pawls are mounted to the cut sheet box
in such a manner as to allow the box to move vertically to some
degree.
In order to realize these functions, the sheet feeding lateral side
of the cut sheet box is made separately from the box body, and arms
are provided on both ends at right angles respectively, and the
sheet feeding lateral side is loosely mounted on the box body. A
separation pawl is provided facing inward on each end of the upper
side of the sheet feeding lateral side, the lower side thereof
being bent along the bottom lower surface of the box body, and the
bottom surface of the box body being inserted into the space
between the lower side and the bottom surface of the arm in order
to prevent the separation pawls from moving over a certain degree.
However, this invention does not require the separation of the
sheet feeding side of the cut sheet box, and, allows the separation
pawls to be provided with a stopper, which controls the sheet
position of the sheet feeding side.
An intermediate plate, which is smaller than the inside of the box
body, is inserted into the box body and, between the intermediate
plate and the bottom springs are provided, which are strong enough
to push up, by way of the intermediate plate, a specified number of
cut sheets, even when the number of sheets is reduced by
consumption, and to press the sheets against the separation pawls
with the proper force.
This invention offers several embodiments for the cassette
mentioned above.
Although there are embodiments in which the feed roller is always
placed on the top sheet in the cassette, the following description
is directed to an embodiment wherein the feed roller rotates and
depresses the sheet only at feeding time.
The feed roller is supported by an arm provided with a shaft, and
is positioned by the force of a spring etc. at a position spaced
apart from the paper surface in the cassette box. The feed roller
may rotate continuously or just at the time of feeding the
sheet.
Upon receiving the feed signal, the arm rotates a certain angle and
the feed roller is pressed on the upper surface of the stacked
sheets. The latter position of this feed roller is always constant,
and is set in such a way that the lowest surface of the feed roller
is slightly lower than the natural position which the uppermost
sheet reaches when the stack of sheets is pushed up by the springs.
Accordingly, the separation pawls are always in position to press
the sheets by their own weight regardless of the height of the
stacked sheets. In other words, the separating action is always the
same even when the number of sheets is reduced and thus the feeding
of a single sheet is performed with assurance.
As mentioned above, because in this invention the paper feeding
position is invariable regardless of the amount of paper, the feed
guide can be made smaller. Because the separation pawls press the
paper with a constant pressure due to their own weight, separation
is assured.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross section of an embodiment of the
invented cassette in a state filled with cut sheets;
FIG. 2 is a longitudinal cross section of the same cassette as
shown in FIG. 1, but the number of the cut sheets has been
reduced;
FIG. 3 is a perspective view of the cassette box of FIGS. 1 and
2;
FIGS. 4 and 5 are longitudinal cross sections of another embodiment
of the cassette means wherein the filing condition of cut sheets
has been gradually reduced by consumption;
FIG. 6 is a perspective view of the said cassette box of FIGS. 4
and 5;
FIG. 7 is a longitudinal cross section of an embodiment of the
invented automatic cut sheet feeding unit shown in a feeding
state;
FIG. 8 is a longitudinal cross section of one portion of said unit
in a state of rest;
FIG. 9 is a perspective view, and
FIG. 10 is a plan view of the cassette box;
FIGS. 11 and 12 are longitudinal cross sections of one portion of a
copying device mounted with cassette means according to another
embodiment;
FIG. 13 is an end view of the device of FIGS. 11 and 12;
FIG. 14 is an enlarged view of the rail section of the body of the
copying device and cassette means;
FIG. 15 is a side view of a cassette for large sized paper (for
example, size A3);
FIG. 16 is a plan view of the cassette of FIG. 15;
FIG. 17 is an enlarged perspective view of the hinge section of the
fixed lid of the cassette;
FIG. 18 is an enlarged perspective view of the engaging section of
said fixed lid and the cassette;
FIG. 19 is a side view of a cassette for small sized paper (for
example, size A4);
FIG. 20 is a plan view of the cassette of FIG. 19 with the lid
removed;
FIG. 21 is a perspective view showing the relationship between the
cassette load signalling element and the switch on the main
unit;
FIG. 22 is a plan view of another embodiment of cassette means;
FIGS. 23 and 24 are the sectional views taken along the line
indicated at IV--IV in FIG. 22;
FIG. 25 is a sectional view taken along the line indicated at
VI--VI of FIG. 23; and
FIG. 26 is a perspective view of the embodiment of FIG. 22.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Several embodiments of this invention will be described in detail
hereafter with reference to the drawings. The embodiments will be
described following the steps of improvement.
In the drawings, 1 is a cassette acceptor contained in a copying
device, 2 is a cassette box which is mounted on the acceptor 1 by
preferably three legs 3 which are detachably mounted on means 4.
The inside of the cassette box 2 must have dimensions, including
proper margins, corresponding to the dimensions of cut sheet P and
must be deeper than the thickness of the stack of a predetermined
number of cut sheets.
An intermediate plate 5 is inserted into the box 2 in such a way as
to allow the plate to move freely in the vertical direction. Spring
6 is provided between the front bottom surface of the plate taken
in the feeding direction, and the box 2 to make the front end
corners of cut sheet P, loaded on the intermediate plate, push
against the separation pawls 7 located on the front corners. The
lid 8 of the cassette box 2 which, after being loaded on the
copying device, is opened at the front lid 8.sub.1 through the
hinge 9 to permit positioning the feed roller 10 in respect of the
sheet seizing roller 11. Moreover, a rotary supporting point 12 is
provided on the back of the rear end of the intermediate plate, as
required.
In the above-mentioned configuration, a predetermined number of cut
sheets are loaded into the cassette box 2 between the separation
pawl 7 and the intermediate plate 5, and are compressed by the
spring 6. When this cassette box 2 is set at the predetermined
position of the acceptor 1 of the copying device as shown in FIG.
2, the separation pawl 7 on the front end takes a predetermined
position in respect of the seizing rollers 11, and the feed roller
10 also makes contact with the top cut sheet P with a predetermined
pressure.
In this case, the mutual relationships between the separation pawl
7, the spring 6, and the feed roller 10 is almost constant and the
force W given to the separation pawl 7 can be maintained almost
constant all the time, regardless of the stack thickness of the cut
sheet P, if the design is made to satisfy the formula ##EQU1##
where C.sub.p = weight per unit load thickness when the maximum
specified number of sheets are loaded and C.sub.w = spring
constant. The free length L.sub.o of the spring 6 is given by
##EQU2## where W.sub.10 = weight of the feed roller 10, W.sub.5 =
weight of the intermediate plate, and L.sub.V = length of the
compressed spring when no cut sheet is loaded.
Therefore, when the feed roller 10 rotates upon receiving a feed
signal, the uppermost cut sheet P is sent out and the separation
pawl 7 prevents two or more sheets from being sent out. When the
cut sheets are gradually reduced in number by consumption, the
intermediate plate 5 is pushed up at the front side first by the
spring 6 thereby pivoting around the rear end supporting point 12.
Thus, regardless of the reduction in the number of cut sheets P,
because the pressing force against the separation pawl 7 is
designed to be almost constant as mentioned above, automatic
feeding of the final sheet is made under the same conditions as the
feeding of the first sheet.
Because the intermediate plate 5 inclines around the rear
supporting point 12, with an increase in its inclination as the
sheets are consumed the gap between its front end and the front
wall 2.sub.1 of the cassette box becomes wider and the area by
which the top sheet P makes contact with the separation pawl 7
becomes narrower. This may disturb the paper feeding and may delay
the feed timing by the amount of the gap.
In order to avoid such dangers, it is desirable to bend the rear
end of the intermediate plate 5 upwardly in an L shape of suitable
dimension so that the upper edge of the L shaped bent section
5.sub.1 descends along the rear wall of the cassette box 2 and
slides the intermediate plate 5 forwardly when the intermediate
plate inclines.
Because the cassette device according to the invention maintains
the cassette box immobile in the body of the copying device, the
upward force of the cut sheets against the separation pawl on the
cassette box caused by the spring acting on the intermediate plate,
is always constant, regardless of the decrease in the supply of cut
sheets:
1. The cassette box is assuredly fixed to the body of the copying
device and, because the fixing method is simple and sure, no
compulsive force is applied to the separation pawls 7 by vibration
or by carelessly pushing the box or by placing something on it, and
the position of the cassette box in not altered.
In other words, the cassette means is very stable as compared to
conventional, known configurations in which the intermediate plate
for carrying the cut sheets is suspended by the support provided on
the body of the copying device and the cassette box itself is made
to move down, gradually;
2. Because the leading end of the cut sheet is always dispensed
from the same position, the cassette can be placed immediately
before the seizing rollers 11 and thus obviate the need for an
auxiliary guide;
3. Even in the case where the cassette is removed from the copying
device, the leading ends of the cut sheets are left seized by the
separation pawls and never get out of place;
4. The pressing force applied to the separation pawls is suitably
chosen and kept almost constant even when the number of cut sheets
has been reduced. Thus the feeding condition is always
constant.
In another embodiment of the invention, the intermediate plate for
carrying the cut sheets is pushed up by springs near its four
corners. This enables the maximum number of cut sheets loaded in
the cassette to be drastically increased.
The configuration is such that the cassette box, which is inserted
in and detached from a fixed position in the copying device, is
formed to have an approximate inner capacity corresponding to the
external form of the cut sheets to be loaded. An intermediate plate
is used to carry the cut sheets, and by pushing up the intermediate
plate near its four corners with springs the cut sheets are pressed
against the lower face of the separation pawls provided at the
front corners of the cassette box and, simultaneously, the cut
sheets are pressed against the ascent stopper, provided on the side
wall of the rear end of the cassette box, with a force insufficient
to disturb the paper feeding. By means of the action of the feed
roller, the top positioned cut sheet is fed over the separation
pawl. As the number of cut sheets increases due to consumption, the
intermediate plate is pushed up so as to always maintain uniform
contact pressure between the cut sheets and the separation
pawls.
However, instead of using the two push-up springs at the rear end,
one push-up spring positioned at the center can be used.
This invention will be described in more detail with reference to
the embodiment shown in FIGS. 4 through 6, in which, 1 is the
cassette holder in the copying device, 2 is the cassette box which
can be detachably set on the receiver 4 of the holder 1 by three or
four legs, in its correct position. The inside of the cassette box
2 has suitable dimensions with proper margins corresponding to the
length and width of the cut sheets P and is made deeper than the
thickness of the stack of a predetermined number of cut sheets
which are to be loaded. The intermediate plate 5 is placed in the
box 2 so as to be free to move vertically, and the spring 6 is
provided between the under surface of the front part of the
intermediate plate, taken in the feeding direction, and the box 2,
and simultaneously the spring 6' is provided at the rear to press
the front end corners of cut sheets up to the separation pawls 7 on
the front corners of the cassette box. At this time, the rear end
part of the cut sheets is prevented by the ascent stopper 13 from
moving up through the cassette box. The cassette box 2 has a lid 8.
A front lid 8.sub.1 is opened by means of a hinge 9, after the box
has been loaded in the copying device, to provide access for the
feed roller 10 to the top cut sheet. There is also provided sheet
seizing roller 11.
In the above-mentioned configuration, a predetermined number of cut
sheets P are loaded into the cassette box 2 between the separation
pawls 7, the ascent stopper 13 and the intermediate plate by
compressing the springs 6 and 6'.
When this cassette box 2 is set to the fixed position on the holder
1 of the copying device as shown in FIG. 5, the separation pawls 7
at its front end take a predetermined position relative to the
seizing rollers 11 and the feed roller 10 also makes contact with
the top positioned cut sheet P with a predetermined pressure.
In this case, the mutual relationship between the separation pawls
7, spring 6, and feed roller 10 is almost settled, and by designing
the relationship so as to satisfy the formula ##EQU3## where
C.sub.p = the weight per unit load thickness when the maximum
predetermined number of sheets are loaded and C.sub.w = the spring
constant, the force W which is applied to the separation pawl can
be always maintained substantially constant, regardless of the load
thickness of cut sheets P. The free length L.sub.o of the spring 6
is given by ##EQU4## where W.sub.10 = weight of the feed roller 10,
W = weight of the intermediate plate, and L.sub.V = length of the
compressed spring when no cut sheets are present. Similarly, by
designing the relationship so that ##EQU5## where C.sub.W ' =
spring constant of the spring 6', the force W' applied to the
ascent stopper 13 can be maintained almost constant. However, these
calculations were made by assuming that the spring 6 and feed
roller 10 are sufficiently close to the leading end of the cut
sheet and that the spring 6' is also sufficiently close to the rear
end of the cut sheet.
When the feed roller 10 rotates upon receiving a feed signal, the
cut sheet P at the highest position is sent out and the separation
pawls prevents additional cut sheets from being sent out. When the
number of cut sheets decreases gradually due to consumption, the
intermediate plate 5 is pushed up by the springs 6 and 6'. And,
because the pressing forces against the separation pawls 7 and
ascent stopper 13 are designed to be almost constant and
independent of the reduction in the cut sheets P, automatic feeding
is performed under the same conditions down to the last sheet.
Thus, the cassette device of this invention keeps the cassette box
set on the body of the copying device immobile and presses the cut
sheets against the separation pawls and ascent stopper of the
cassette box by gradually pushing up the intermediate plate, which
is placed in the cassette box, and always maintains constant
pressing forces, independent of the reduction in the number of cut
sheets.
Another embodiment is shown in FIGS. 7 through 10. The top side of
the container box 2 is open, and the feeding side, lateral side
45.sub.2, is made separately from the body of the box. Arms
45.sub.5 are provided at right angles at both ends of the lateral
side 45.sub.2, and it is loosely mounted to the body of the box
through shafts 45.sub.4. A separation pawl 45 is provided on each
end of the upper side of the lateral side 45.sub.2, facing
inwardly, and the lower side 45.sub.5 is bent along the lower
surface of the bottom of the body 2 and the bottom 2.sub.1 of the
body is inserted into the space between the lower side 45.sub.5 and
the bottom of the arm 45.sub.3 to prevent the separation pawls 45
from moving beyond a certain degree. Ascent stopper 13 of the sheet
is provided at the corner of the rear end (on the opposite side
from the feeding side) of the box body 2.
An intermediate plate 43, which is slightly smaller in demensions
than the inside dimensions of the box body, is placed in the box 2,
and a flat spring (or a coil spring) 44 is provided between the
intermediate plate and the bottom 2.sub.1. The spring 44 is of
sufficient strength to push up a predetermined number of sheets of
paper P via the intermediate plate 43 and to press the paper P
against the separation pawls 45 and ascent stopper 13 with a
suitable force, even when the amount of paper has been reduced by
consumption. In this case the bent edge 45.sub.3 of the bottom of
the lateral side 45.sub.2 is in contact with the back of the bottom
2.sub.1 of the body, as shown in FIG. 8. When the number of sheets
loaded and contained is small, it is only necessary to push up the
feeding side of the intermediate plate 43 to incline plate, leaving
its rear end in contact with the bottom 2.sub.1 of the box.
The feed roller 46 is supported by the arm 134 which is provided
with a shaft 120. The arm 134 is coupled to the feed lever 133 by,
for example, a pin 134 mounted in a elongated hole 133.sub.1. The
roller 46 is positioned spaced apart from the paper face in the box
by the spring 134.sub.2 and rotates either continuously or rotates
only at the time of feeding the paper.
When, by the feed signal, the shaft 131 and lever 133 rotate
clockwise by a fixed angle, the arm 134 rotates counterclockwise by
a fixed angle to press the roller 46 against the upper face of the
loaded paper P. The lower position of the roller 46 is always
constant and, at this time, the lower end face of the roller is so
set as to be slightly below the natural position of the
top-positioned copying paper P which has been pushed up by the
spring 44. Therefore, the roller 46 first makes contact with the
uppermost copying paper and then comes down to the predetermined
position by pressing down the copying paper, against the spring 44,
and feeds the paper by its own rotation.
During this time, the separation pawls 45 go down around the shaft
45.sub.4 caused by the weight of the entire lateral side 45.sub.2,
with the descent of the copying paper P, and further, since the
hole on the box body, which corresponds to the shaft 45.sub.4 is
oblong in the vertical direction (oval hole), the separation pawls
on both ends make contact with the copying paper P without being
forced, and accordingly the separation pawls 14 press the copying
paper P by their own weight. Therefore the separating action is
always the same even when the amount of the paper has been reduced
and thus the paper is fed assuredly, one sheet at a time.
Because this invention has the above-mentioned configuration, the
dispensing position of the copying paper is invariable regardless
of the amount of the paper, and the feed guides 48.sub.1 and
48.sub.2 can be made small and compact.
As the separation pawls 45 press the paper with a constant pressure
due to their own weight regardless of the amount of the paper, the
separating action is effected without fail. The configuration, in
which the spring 44 pushes up the paper when the amount of copying
paper has been reduced, serves only to compensate for the change in
the height of the upper surface of the copying paper.
The device of the present invention is simple and stable as
compared with the prior art devices in which the paper was
supported by an intermediate plate and, as the paper decreased the
body of the box was lowered.
In the drawing, 8 and 8.sub.1 show a lid for preventing dust and
light from entering into the cassette. At time of use, the snatch
lid 8.sub.1 is opened and can be made to serve as the tray for
copied paper coming from the main unit.
Next, a cassette means which also serves as a tray will be
described, referring to FIGS. 11 through 21.
FIG. 11 shows a small-sized cassette means 2 is mounted on the body
1 of a copying device. FIG. 12 shows a large-sized cassette means 2
mounted on the body of a copying device. As shown in the left end
view FIG. 13, and the partially magnified end view in FIG. 4, the
cassette 2 is provided with a rail-shaped projection 21 on the
front and rear surfaces and is guided by the rail 154 when being
mounted or detached. The lid of the cassette 2 is divided into two
parts, a fixed lid 8 and a movable lid 8.sub.1, both lids being
coupled by means of a hinge 9. When the movable lid 8.sub.1 is
opened and reversed and placed on the fixed lid 8, a part of the
movable lid projects rearwardly from the cassette 2 to form a copy
tray, as shown in FIGS. 15 and 16. The free end bent edge 81' of
the movable lid 8.sub.1 serves as a lid covering the lateral side
of the cassette and as a copy stopper when the lid is converted to
a tray.
In FIG. 16, two lids 8 and 8.sub.1 are overlayed at portion l,
which is opened when the movable lid 8.sub.1 is opened, and there
the feed roller 46 acts on the sheet P. The distance between the
copy discharge port 62 of the copying device body 15 and the
stopper 8.sub.1 ' of the copy tray is determined by the position of
the hinge 9 of the movable hinge 81 for each size of cassette to
correspond to the length of each size of copying paper.
In FIGS. 11 and 12 where there is a big difference in height
between the positions of the discharge port 62 and the cassette 2,
an auxiliary tray 14 is attached to the body of copying device to
form a copy tray together with the lid tray 81. To make use of the
auxiliary tray 8 in such a way that it can be removed when part 62
and lid 8.sub.1 are positioned close to each other is an effective
means in the design, because it offers a great deal of freedom in
the layout of the cassette.
FIG. 18 shown a projection 8.sub.11 and mating groove 2.sub.11
which are used to hinge the fixed lid 8 to the cassette 2. Thus,
the lid 8 is fixed to the cassette by 8.sub.11, 2.sub.11, and the
front bent edge 8.sub.1. When the cassette 2 is mounted in its
predetermined position on the body 15, the cam 2.sub.2 on the back
of the cassette pushes the switch MS19 on the body and transmits a
load signal. Holes 43.sub.1 and 2.sub.4 penetrate through the
intermediate plate 43 and the bottom plate of the cassette and, by
the function of photoelectric unit 155 and 156, a signal is issued
when the cassette is empty of copying paper. On the back of the
cassette for sizes A4 or less, a cam 2.sub.3 (FIGS. 19 and 20) is
provided which serves to change-over the machine cycle to A4 copy
cycle by depressing the switches MS13 and MS16. On the back of the
cassettes larger than that for size A4, no such cam acting on the
above-mentioned switches MS13 and MS16 is present (FIGS. 15 and 16)
and the machine operates in an A3 copy cycle. In the drawing, 46 is
the feed roller, and 45 in FIG. 20 is the sheet separation
pawl.
Next, an example of a cassette will be described in which the feed
side lateral side 46.sub.2 of the cassette 2 is made separately
from the box of the cassette body, and a separation pawl 45 is
provided on each upper end of the lateral side 46.sub.2. The side
46.sub.2 is made to move vertically with respect to the body box by
means of the arm 45.sub.3 and shaft 45.sub.6, so that, when the
loaded paper P is pushed down to a predetermined position by the
feed roller 46, the separation 45 and the lateral side 46.sub.2
follow the paper P by virtue of their own weight.
Another embodiment of the invention is shown in FIGS. 22 through
25. Although the cassette is so designed that the paper load in the
cassette is pushed down a certain degree by the feed roller, the
separation pawl also lowers itself by its own weight, and by the
joint action of the revolution of the feed roller and the
separation pawl, one sheet of paper is separated and sent out to
the body. However, in order to assure the one sheet separation, an
auxiliary means is provided in practical use. In this invention,
the lateral side parallel to the feed direction is lightly pressed
by using sponging plastic etc. This is called the side presser 17.
In order to be sure to press the side of the paper, the
above-mentioned side presser 17 is positioned inside the paper
width at its free position.
The paper pressing part of each of the pair of side pressers shown
in FIG. 25 receives the force from the spring 18 to improve the
effect when the paper is loaded. In FIG. 25 the side presser 17 is
pressed by the spring to the position shown by an alternate long
and two short dashes line. At this time, the interval between the
pair of side presser 17 is narrower than the paper width and the
upper section 16 of the side presser is inclined. Due to this
inclination, the side presser 17 receives a force opposite to the
force of spring 18 and is moved in the direction of the arrow when
the paper is loaded from above the side presser 17. When the paper
loading is finished, presser presses the lateral side of the paper
with assurance by the force of the spring. Accordingly, there is no
need of moving the side presser by hand when loading paper and,
thus, the merit of the cassette system is fully displayed.
* * * * *