JPH07232833A - Paper feed tray device for image forming device - Google Patents

Abstract

PURPOSE:To enable paper feed action without lifting up the paper sheets and without swinging a pickup roller, etc., largely when a tray is fit in a paper feed part by forming the height of a front frame of the paper feed tray lower than that of the paper sheets at its max. accommodation. CONSTITUTION:A front frame 15 disposed on the paper feed side of a paper feed tray 10 is made up at a height lower than that of max. accommodation time of paper sheets and shutter pieces 20, 20a are slidably mounted against the front frame 15. An actuating arm member 25 for moving the shutter pieces up and down is arranged therein and the shutter pieces are moved downward on the way of action for fitting the tray in a paper feed part so as to form a front opening 17 widely. Thereby, paper feed action can be started without lowering a pickup roller largely and without performing any action for lifting the paper sheets in the tray when the paper sheets are delivered out by the pickup roller 3 of a paper feed device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed tray which is mounted on a paper feed section of an image forming apparatus and used for feeding paper, and more particularly, the height of a front frame of the tray is set to a maximum for accommodating paper. The present invention relates to a paper feed tray device of an image forming apparatus that is configured to be lower than the height so that a paper feeding operation can be performed in a state where the paper is not raised when the paper is delivered.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic copying machine or a laser beam printer, a plurality of paper feed trays are arranged in a paper feed section and sheets of different sizes are accommodated in the paper feed trays. In addition, it is configured such that a paper of a size corresponding to the size of a document can be fed. The sheet feeding tray arranged in the sheet feeding unit is configured as shown in, for example, Japanese Patent Laid-Open No. 2-276736, Japanese Utility Model Laid-Open No. 64-26646, and the like in order to raise the sheet in the tray. The bottom plate member is disposed on the paper feed unit main body, and a lifting arm member for raising the bottom plate member is provided in the sheet feeding unit main body. Then, with the paper feed tray attached to the paper feed unit of the image forming apparatus, the bottom plate member is raised by the push-up arm member to press the paper against the feed roller member of the paper feed device and rotate the roller member. Thus, the paper can be sent out.

As a sheet feeding device arranged in the sheet feeding portion of the image forming apparatus corresponding to the sheet feeding tray, for example, a device having a structure as shown in FIG. 6 is used. The example shown in FIG. 6 is disclosed in Japanese Unexamined Patent Publication No. 3-192036, in which the pickup roller 3 arranged corresponding to the paper feeding portion of the paper feed tray 10c and the paper arranged downstream thereof. The sheet feeding device 1 is configured by combining the sorting device 5. The pickup roller 3 as the paper feed roller member is provided with a swing arm 4 with respect to a shaft 6a of a paper feed roller 6 which constitutes the paper sorting device 5.
It is swingably supported via a. When the paper is sent out from the paper feed tray 10c, the swing arm 4a is used.
Is oscillated counterclockwise about the shaft 6a, and the pickup roller 3 is rotated while pressing it onto the paper so that the paper is fed toward the paper separating device 5. In the sheet separating device 5, a sheet feeding roller 6 rotating in the sheet feeding direction and a retard roller 7 rotating in the sheet returning direction are arranged to face each other, and two or more sheets are fed between the rollers in a double-feed state. In this case, only the upper paper is sent out by the paper feed roller 6, and the lower paper is returned by the retard roller toward the tray side.

The pick-up roller 3 provided in the paper feeding device swings an arm 4a by driving means (not shown) during the operation of feeding the paper from the paper feeding tray 10c.
Is provided to release the state where the pickup roller 3 is pressed against the paper. The pickup roller does not interfere with the operation of pressing the paper when the paper is fed out by the paper separating device and the conveying roller device arranged downstream of the paper separating device. Further, the bottom plate member 12 that supports the paper inside the paper feed tray is swingably provided via a hinge portion provided at a predetermined position of the bottom frame 11 of the paper feed tray 10c, and is provided in the image forming apparatus. The bottom plate member 12 is raised by the push-up arm member 9 which is disposed on the paper portion and is supported by the drive shaft 9a. Then, the bottom plate member 12 is lifted by the push-up arm member 9 so that the upper surface of the paper is maintained at a constant height, and the bottom plate member is gradually lifted while following the paper feeding operation. The upper surface of the roller can be brought into contact with the pickup roller at a constant pressure.

[0005]

However, in the conventional paper feed tray as described above, the height of the front frame of the tray is set in accordance with the maximum number of sheets of paper that can be accommodated. When feeding the paper, it is necessary to raise the paper by the bottom plate member so that the upper surface of the paper projects higher than the front frame. Further, it is necessary to lower the pickup roller provided in the sheet feeding device when the sheet is fed, and then hold the pickup roller in a position where the pickup roller is raised. A space for moving the pickup roller up and down is required in the upper part of the paper feed section of the paper feed tray corresponding to the vertical movement interval H of the pickup roller, and a swing for supporting the pickup roller is required. A drive mechanism for the moving arm is provided along with the sheet feeding device. Therefore, in the conventional sheet feeding device, when a plurality of sheet feeding trays are arranged in a stack in the sheet feeding unit of the image forming apparatus in order to arrange a large margin above the sheet feeding unit of the sheet feeding tray. Requires an extra space between the upper and lower paper feed trays, which limits the number of sheets that can be stored in the paper feed unit.

Further, in the conventional paper feeding tray, it is necessary to set a large distance for raising the paper with respect to the paper feeding device arranged at the upper part, so that the swinging range of the push-up arm member can be increased. The drive mechanism is installed.
Therefore, in order to set the swing range of the push-up arm member to be large, it is necessary to provide a large space corresponding to the push-up arm member, and it is necessary to provide a marginal portion also at the lower part of the paper feed tray. To be done. Therefore, when the conventional paper feed trays are arranged in a stack to form a paper feed unit, there is a problem that the number of sheets of paper that can be accommodated is limited because an extra space is provided above and below the tray body. However, there is a drawback that it hinders downsizing of devices such as electrophotographic copying machines.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional paper feed trays. The front frame of the tray is configured to have a height lower than the maximum storage height of paper, and a large quantity of paper is stored. By configuring so that the paper feeding operation can be performed without raising the bottom plate member, and by lowering the height at which the bottom plate member is raised even when the paper feed amount is small, the space available above and below the tray can be reduced. It is an object of the present invention to provide a device that enables downsizing of the configuration of the paper feeding unit.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a bottom plate member for stacking sheets is provided so as to be vertically movable in a sheet storage portion of a tray.
A device configured to press a sheet against a feed roller member of a sheet feeding device arranged corresponding to the sheet feeding side of the tray and to feed the sheet while separating the sheet by a sheet separating device arranged downstream of the feeding roller. Regarding In the present invention, the front frame of the paper feeding tray in the paper feeding direction is configured to be lower than the maximum height of accommodating paper, and the bottom plate member is raised with the paper feeding tray set in the paper feeding unit of the image forming apparatus. It is configured so that the paper can be sent out without it.

Further, in the present invention, a shutter member for restricting a front end portion of the sheet in the sheet feeding direction is arranged with respect to the front frame of the sheet feeding tray at a position corresponding to the maximum storage height of the sheet in the tray. Along with this, means for retracting the shutter member in the height direction with respect to the front frame is provided, and the shutter member regulates the front end of the paper by the operation of mounting the paper feed tray in the paper feed unit of the image forming apparatus. Release the state,
It is possible to provide a driving unit that regulates the front end portion of the sheet by the shutter member when the sheet feeding tray is removed from the sheet feeding unit. Further, in the present invention, a driving means for retracting the shutter member with respect to the front frame is provided in an operating arm member that is movable back and forth in the mounting direction of the tray with respect to the sheet feeding portion, and in the movement of the operating arm member. A member configured to follow the shutter member up and down to move up and down, and is provided with a means for urging the operating arm member to the front side in the mounting direction of the tray, and a member for locking the leading end of the operating arm member in the paper feed tray. Can be placed.

[0010]

As described above, the shutter member is provided so as to be vertically retractable with respect to the front frame of the paper feed tray, and the actuating arm member movable in the tray attaching / detaching direction is arranged to drive the shutter member. However, an operation member for the operation arm member is provided on the rear side of the paper feeding unit. Then, by moving the operation arm member in the direction of pushing back by the operation of mounting the tray, and by lowering the shutter member in conjunction with the operation arm member, a large opening is formed in the upper part of the front frame and the paper is raised. The pick-up roller can start the feeding operation even without it. Further, in the paper feeding device arranged in the paper feeding portion corresponding to the paper feeding tray of the present invention, it is not necessary to provide a mechanism for moving the pickup roller up and down, and the paper is only slightly raised by the bottom plate member, It is possible to carry out the feeding operation, and it is not necessary to provide a large space above the tray corresponding to the paper feeding device. Further, in the tray of the present invention, since a large opening is provided on the front side, it is not necessary to set a large interval for raising the paper, and no extra space is provided in the lower part of the tray. A sheet of paper can be accommodated, and the device can be downsized.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sheet feeding tray device of an image forming apparatus of the present invention will be described with reference to the illustrated example. In the example shown in FIG. 1, in the paper feed tray 10 of the present invention, as in the case of the conventional tray, a frame body corresponding to the maximum accommodating height of paper is arranged around the paper accommodating portion, and the paper P A bottom plate member 12 on which the is mounted is swingably provided on the bottom frame 11. Also,
In the example shown in FIG. 1, the front frame 15 arranged to regulate the front end portion of the sheet in the sheet feeding direction is configured to project lower than the other side frames, and with respect to the front frame 15. The shutter member 16 is provided slidably in the vertical direction. When replenishing the paper feed tray 10 with paper or the like, the shutter member 16 is held in the raised position in a state where the paper feed tray is pulled out from the paper feed unit of the image forming apparatus, and other side frames are held. I am trying to maintain the same height.

Further, when the paper feed tray 10 is mounted in the paper feed section of the image forming apparatus, as shown in FIG.
The shutter member 16 descends along the front frame 15, and a front opening 17 is formed in the front portion of the tray on the sheet feeding side so that the operation of feeding the sheet can be accommodated. In the paper feeding unit of the image forming apparatus in which the tray is mounted, like the conventional paper feeding device, the pickup roller 3 arranged corresponding to the leading end of the tray on the paper feeding side, the paper separating device 5, and A push-up arm member 9 for pushing up the bottom plate member 12 is arranged. Then, each operating member arranged in the paper feeding device performs an operation in accordance with the timing of each operation via a unit that receives a driving force from the paper feeding unit main body. In the paper feeding device, the pickup roller 3 is driven in association with the drive shaft 6a of the paper feeding roller of the paper separating device. The pickup roller 3 is picked up via the support link 4 from the drive shaft 6a of the paper feeding roller 6. 3, a mechanism that supports the drive roller 3 and transmits the drive to the pickup roller is configured. Further, the retard roller 7 is the drive shaft 7
Drive is performed via a torque limiter 8 between a and
When the sheet is fed while being separated, the retard roller can be rotated in the sheet feeding direction according to the friction between the sheet and the retard roller 7.

As shown in FIG. 1, in the paper feed tray 10 in which the shutter member 16 is movable up and down with respect to the front frame 15, as shown in FIG. Accordingly, a mechanism for automatically lowering the shutter member 16 can be configured. And the paper feed tray 1
When a large amount of paper is stored in 0, it is possible to feed the paper through the front opening without raising it. In the state shown in FIG. 2, when the paper feed tray is attached to the paper feed portion, the shutter member 16 automatically descends to form the front opening 17, so that the pickup roller 3 is only pressed against the upper surface of the paper. Then, it becomes possible to start the operation of feeding the paper. Therefore, the paper feeding operation can be continued without raising the bottom plate member 12 until the height of the paper stored in the tray reaches a predetermined position with respect to the upper surface of the front frame 15, for example. After that, it is possible to raise the push-up arm member 9 via the drive shaft 9a so that the sheet feeding operation can be performed while gradually raising the sheet.

Further, in the paper feeding apparatus of the present invention, the pickup roller 3 is arranged at a fixed position with respect to the support frame 2, the paper feeding tray 10 is mounted, and then the bottom plate member 12 is used by using the push-up arm member 9. Is raised and the upper surface of the paper is pressed against the pickup roller 3, so that the paper feeding operation can be performed. As described above, when the pickup roller 3 is arranged at the fixed position, a mechanism for moving the pickup roller 3 up and down is not required, so that it is possible to simplify the mechanism of the sheet feeding device. It is possible to reduce the thickness of the paper feeding device arranged above the paper feeding side of the tray. Then, when the paper is sent out by the pickup roller 3 arranged at the fixed position, the pickup roller 3 of the pickup roller 3 is formed with a very small gap with respect to the maximum storage height of the paper stored in the paper feed tray 10. The position can be set. Therefore, by configuring the shutter member 16 to be movable up and down with respect to the front frame 15, it is possible to easily perform the operation of feeding the paper from the paper feeding tray without setting a large interval for raising the paper. become.

As described above, when the shutter member 16 is provided so as to be vertically movable in correspondence with the front frame of the paper feed tray, the shutter member is vertically moved as shown in FIGS. 3 to 5, respectively. The mechanism can be configured. In the example shown in FIG. 3, the shutter pieces 20 and 20a are used as the shutter members to be projected and retracted in the upper portion of the front frame 15, and the front opening 17 of the tray is closed by raising the shutter pieces. The case where a mechanism that can form the front opening 17 by lowering the shutter piece is provided is shown. In the example shown in FIG. 3, the paper feed tray 10 is provided with a handle 13 at a position corresponding to the front side of the image forming apparatus, and the paper feed tray is attached to and detached from the paper feed unit using the handle 13. Constitutes a means.

A plurality of guide members 28, 28a are arranged on the front frame 15 of the paper feed tray, and an operating arm member 25 guided by the guide members is provided. The tip portion 25a of the above is urged by a spring 29 so as to project. When the actuating arm member 25 is arranged on the outer surface of the front frame 15 of the tray on the side of the paper storage portion, the guide members 23 and 24 for guiding the shutter piece in the vertical movement direction are projected to the outside of the front frame. To be provided. In addition, the operating arm member 2
When arranging 5 on the outside of the tray (outer surface in the sheet feeding direction), the distal end of the operating arm member is arranged so as to project to the rear side from the opening provided in the side plate of the tray. Further, the distal end portion 25a of the actuating arm member 25 is configured to project from the distal end portion on the rear side (insertion direction) of the tray by a predetermined length. Then, the tip end portion 25a of the operation arm member 25 may come into contact with a wall member or a convex member provided in the paper feeding unit main body during the operation of mounting the paper feeding tray in the paper feeding unit of the image forming apparatus. Thus, the operation arm member 25 is retracted to the front side.

Projecting members 26, 26a are arranged on the upper side of the actuating arm member 25 at a predetermined interval, and the projecting members are formed corresponding to the projecting and retracting heights of the shutter pieces 20, 20a. On the other hand, inclined surfaces are formed on both sides in the moving direction of the actuating arm member so that, as will be described later, the action of vertically guiding the shutter piece with respect to the leg member can be performed well. Further, the shutter pieces 20 and 20a arranged so as to be movable up and down with respect to the front frame 15 are
It is provided so as to be guided in the vertical movement direction by the guide members 23 and 23a provided in the above and the guide members 24 and 24a. Further, leg members 21 and 21a are provided so as to project below the shutter pieces 20 and 20a, and the lower portion of the leg member is placed on the convex members 26 and 26a provided on the operation arm member 25. It is provided in a ready state.
Then, the leg member is pressed against the convex member by the own weight of the shutter piece, and the operation arm member moves the shutter piece up and down in accordance with the movement in the length direction by the operation of attaching and detaching the paper feed tray. Be able to do it. In addition,
In the example shown in FIG. 3, the pickup roller 3 arranged in the paper feeding section corresponding to the paper feeding tray can be arranged with a very small gap to the side frame of the tray. When installing or removing the paper tray, make sure that the rollers do not touch the side frames.

In the paper feed tray 10 shown in FIG.
When it is mounted in the paper feed unit of the image forming apparatus, the front end portion 25a of the operation arm member 25 is opposed to the regulating member on the rear side of the paper feed unit.
Are contacted with each other and the paper feed tray is further inserted, so that the operation arm member 25 slides in the width direction with respect to the front frame. By the movement of the operation arm member, the lower end of the leg member of the shutter piece slides on the slope from the upper part of the convex member to lower the shutter piece.
20a descends along a guide member provided on the front frame 15,
The upper surface of the shutter piece is at the same height as the upper surface of the front frame 15, and the front opening 17 is formed wide. Further, when pulling out the paper feed tray from the paper feed section, the restriction effect on the tip end portion of the operation arm member 25 is released, so the spring 2 arranged with respect to the operation arm member 25 is released.
9, the actuating arm member 25 is moved to the right side in the figure, so that the convex member provided on the actuating arm member moves with respect to the leg member and pushes up the shutter piece, so that the shutter piece opens the front opening. The closing operation is performed automatically. Therefore, the front opening corresponding to the front frame is not formed when the paper tray is pulled out to replenish the paper or when the paper is stored in the paper tray. The paper can be stored in a stable state.

[0019]

Second Embodiment In addition to the example shown in FIG. 3, the paper feed tray of the present invention has shutter pieces 30, 30a as shown in FIG.
It is also possible to configure the paper feed tray 10a provided with. In the example shown in FIG. 4, the paper feed tray 10
Shutter pieces 30 and 30a are swingably provided to the front frame 15 of a via support shafts 34 and 34a, respectively. Then, the upper surface of the shutter piece is formed in an arc shape so that the front opening 17 can be opened in a state where the shutter piece is swung clockwise at a small angle. The shape of the arc formed on the upper surface of the shutter pieces 30 and 30a is formed corresponding to the angle at which the shutter pieces swing through the support shafts 34 and 34a. When the tip end of the upper side of the piece is set at almost the same height as the other side frame of the tray and the shutter piece is swung, the upper surface of the shutter piece is the front frame 15.
It should be held at almost the same position as the height of.

In the shutter pieces 30, 30a, long leg members 31, 31a are provided so as to project downward, and the leg members have elongated holes 32, 32a.
And the pin members 33 and 33a provided on the operating arm member 35 are engaged with the elongated holes. Therefore,
The shutter pieces 30 and 30a are swung following the movement of the operating arm member in the lengthwise direction, and the tip end of the shutter piece performs an operation of closing the front opening and an operation of opening the front opening. Thus, the elongated holes formed in the leg members of the shutter piece can respond to the change in the engagement position of the pin members 33 and 33a in response to the movement of the operation arm member. The operating arm member 35 is shown in FIG.
Similarly to the above case, it can be provided so as to be movable along an arbitrary surface inside and outside the front frame 15, and the arrangement positions of the pin member, the leg member and the like are set according to the arrangement state of the operating arm member 35. It

The actuating arm member 35 arranged corresponding to the leg member of the shutter piece has long holes 36, 3 in the length direction.
6a is provided, and the pin members 37, 37a provided on the front frame 15 are engaged with the elongated holes to guide the movement of the operating arm member in the longitudinal direction. The elongated holes 36, 36a provided in the operating arm member are formed according to the moving distance of the operating arm member, and the operating arm member is set as an elongated hole with respect to the pin member provided in the front frame. Be able to move only a distance. Further, the tip end member 35a of the operating arm member 35 is provided so as to project toward the rear side of the tray by a predetermined length, and a spring 39 is provided between the front frame and the predetermined position of the operating arm member. , So that the protruding state of the operating arm member toward the rear side is maintained.

When the shutter piece constructed as described above is used, the tip end portion 35a of the operating arm member is moved to the rear side of the sheet feeding section during the operation of mounting the sheet feeding tray 10a in the sheet feeding section. Engage with the arranged regulating member. Then, by further continuing the operation of inserting the tray, the operating arm member 35 is relatively moved in the direction opposite to the moving direction of the tray. Following the operation of moving the operation arm member 35 with respect to the front frame, the pin members 33 and 33a provided on the operation arm member support the shutter piece through the long holes provided on the leg member of the shutter piece. Since it is swung clockwise through the shafts 34 and 34a, the projecting portion of the shutter piece is lowered to a position lower than the upper surface of the front frame 15 so that the front opening 17 can be formed.
Therefore, also in the paper feed tray shown in FIG. 4, the operation of inserting the paper feed tray 10a into the paper feed unit of the image forming apparatus lowers the shutter piece located above the front frame 15 to lower the paper. The front opening for sending out can be set to a large size to accommodate the paper feeding operation.
Further, when the paper feed tray is pulled out from the paper feed section, the shutter piece is swung in the direction of closing the front opening by the force of the spring 39, and when the paper is replenished, the paper is fed in the tray in the paper feed direction. It prevents the sheets from being stored in an unstable state by popping out from the front side.

[0023]

[Embodiment 3] Besides constructing the paper feed tray as shown in FIGS. 3 and 4, in the present invention, as shown in FIG. 5, a mechanism for opening and closing the shutter piece by using a link mechanism. It is possible to configure the paper feed tray 10b provided with. In the paper feed tray 10b, the shutter pieces 40, 4
0a is arranged so as to be vertically movable, and is guided by the pin members 43 and 43a to the front frame 15 through the long holes 42 and 42a provided in the leg members 41 and 41a of the shutter piece. Further, the operation arm member 45 provided so as to be movable in the width direction of the front frame is the pin member 4 provided so as to project from the front frame.
7 and 47a are provided so as to be guided through the long holes 46 and 46a. Then, the tip end portion 45 of the operating arm member urged to the rear side of the tray by the spring 49.
As in the case of the actuating arm member of the above-described embodiment, a is held at a position projecting to the rear side of the tray by a predetermined length. Further, the actuating arm member 45 is provided with projecting arms 48 and 48a projecting upward by a predetermined length, and a link member 50 is provided between the projecting arm 48 and the lower portion of the leg member 41. The link member 50 is provided with a support shaft 50b at the center thereof, and the support shafts 51 and 52 are slidably connected by sliding the support shafts 51 and 52 with respect to the long holes at both ends. Similar to the case of the shutter piece 40, the upper end of the protruding arm 48a and the lower end of the leg member 41a of the shutter piece 40a are connected to the shutter piece 40a by using a link member 50a.

By configuring the shutter piece moving means as described above, in the paper feed tray 10b of the present invention,
Similar to the case of the previous embodiment, the operation arm member is moved in opposition to the insertion direction by the operation of inserting the operation arm member in the sheet feeding portion of the image forming apparatus. Then, by the movement of the operating arm member 45 relative to the front frame,
In the shutter piece 40 on the right side of the drawing, the distance between the protruding arm 48 and the leg member 41 is narrowed, the link member 50 swings counterclockwise via the upper support shaft 51, and the leg member via the support shaft 52. The operation of pulling down 41 is performed. Therefore, the leg member 41 moves the shutter piece 40 downward while the elongated hole 42 is guided along the pin member 43, and the upper surface of the shutter piece 40 reaches substantially the same height as the upper surface of the front frame 15. By being lowered, the front opening 17 is formed on the upper side of the front frame, and it is possible to correspond to the operation of feeding the paper.
In the other shutter piece 40a, the leg member 41a is moved downward via the pin member 43a by using the projecting arm 48a and the link member 50a provided on the actuating arm member, which corresponds to the operation of opening the front opening. be able to.

As described above, by the operation of mounting the paper feed tray 10b in the paper feed section of the image forming apparatus, an opening is formed in the upper portion of the front frame 15 of the paper feed tray so that the paper is not raised significantly. Be able to perform the action of feeding the paper. Further, when the paper feed tray is pulled out from the paper feed section, the operating arm member 45 is moved in the rear direction of the tray by the spring following the pulling operation, so that the operating arm member 45 is moved relative to the front frame. Moved to the right side of the figure. Then, the protruding arms 48, 48a provided integrally with the operating arm member are separated from the leg member,
The projecting arm rotates clockwise through the upper support shaft to move the shutter pieces 40, 40a upward, thereby closing the front opening. Therefore, even when the shutter piece as shown in the paper feed tray 10b is arranged, the front frame arranged on the paper feed side of the tray is configured to be low and the shutter piece is retracted from the front opening. It becomes possible to do.

Incidentally, with respect to the paper feed tray of the present invention,
When the shutter member is arranged so as to be retractable along the front frame, and the shutter member is composed of a plurality of shutter pieces, the front opening is opened in accordance with the operation of attaching / detaching the paper feed tray to / from the paper feed unit. It can be opened and closed. Further, in each of the embodiments of the shutter piece, the shape and the like of the upper end portion of the shutter piece body can be arbitrarily configured, and in order to perform operations such as vertical movement and swing of the shutter piece. In addition, it is possible to provide a guide member or the like arranged with respect to the shutter piece in combination with a mechanism used for guiding conventional general members other than the illustrated members.

[0027]

As described above, in the paper feed tray device of the image forming apparatus of the present invention, the shutter member is provided so as to be vertically retractable with respect to the front frame of the paper feed tray to drive the shutter member. It is also possible to arrange an operating arm member that is movable in the attachment / detachment direction of the tray, and to provide an operating member for the operating arm member on the rear side of the paper feeding unit. Then, the operation arm member is moved in the direction to be pushed back by the operation of mounting the paper feed tray on the paper feed unit of the image forming apparatus main body, and the shutter member is lowered in conjunction with the operation arm member, so that the upper portion of the front frame is moved. Even if a large opening is formed and the paper is not raised, the pickup roller can start the paper feeding operation. Further, in the paper feeding device arranged in the paper feeding section corresponding to the paper feeding tray of the present invention, it is not necessary to provide a mechanism for moving the pickup roller up and down, and the paper is only slightly raised by the bottom plate member,
The paper can be fed out, and it is not necessary to provide a large space above the tray corresponding to the paper feeding device. Further, in the tray of the present invention, since a large opening is provided on the front side, it is not necessary to set a large interval for raising the paper, and no extra space is provided in the lower part of the tray. A sheet of paper can be accommodated, and the device can be downsized.

[Brief description of drawings]

FIG. 1 is a side view of a paper feed tray of the present invention.

FIG. 2 is an explanatory diagram showing a state in which the paper feed tray of the present invention is attached to a paper feed unit.

FIG. 3 is an explanatory diagram of a paper feed tray of the present invention.

FIG. 4 is an explanatory diagram of a second embodiment of a shutter piece provided in the paper feed tray of the present invention.

FIG. 5 is an explanatory diagram of a third embodiment of a shutter piece provided in the paper feed tray of the present invention.

FIG. 6 is an explanatory diagram showing a configuration of a conventional paper feed tray and a paper feed mechanism.

[Explanation of symbols]

1 paper feeding device, 3 pickup rollers, 5
Paper sorting device, 6 paper feed roller, 7 retard roller, 9 push-up arm member, 10 paper feed tray, 12 bottom plate member, 15 front frame, 16
Shutter member, 17 front opening, 20 ・ 30 ・
40 shutter pieces, 21 leg members, 25/35
.45 working arm members, 28 guide members, 2
9.39.49 springs, 48 protruding arms, 50 link members.

Claims (3)

[Claims] 1. A bottom plate member for stacking sheets is provided so as to be vertically movable in a sheet storage portion of a tray, and the sheet is pressed by a feed roller member of a sheet feeding device arranged corresponding to the sheet feeding side of the tray to feed the sheet. In an apparatus configured to supply a sheet while separating the sheet by a sheet separating device arranged in a downstream portion of the roller, a front frame of the sheet feeding direction of the sheet feeding tray is configured to be lower than a maximum accommodating height of the sheet, A sheet feeding tray device of an image forming apparatus, wherein the sheet feeding tray is set in a sheet feeding section of the image forming apparatus, and the sheet can be fed out without raising a bottom plate member. 2. A shutter member for restricting a front end of a sheet in the sheet feeding direction is arranged at a position corresponding to a maximum storage height of the sheet in the tray with respect to a front frame of the sheet feeding tray, and the shutter member. Is provided in the height direction with respect to the front frame, and the state in which the shutter member regulates the front end of the sheet is released by the operation of mounting the sheet feeding tray in the sheet feeding section of the image forming apparatus, 2. The paper feed tray device for an image forming apparatus according to claim 1, further comprising drive means for restricting the front end of the paper by a shutter member when the paper feed tray is removed from the paper feed section. 3. A driving means for moving the shutter member in and out of the front frame, the operating arm member being movable back and forth in the mounting direction of the tray with respect to the sheet feeding portion, and following the movement of the operating arm member. The shutter member is moved up and down to provide a means for urging the operating arm member to the front side in the mounting direction of the tray, and a member for locking the tip of the operating arm member is arranged in the paper feed tray. The sheet feeding tray device of the image forming apparatus according to claim 1, wherein