JPH0662223B2 - Transfer paper supply device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a transfer paper supply device in an image forming apparatus, and more particularly, to a transfer paper supply device in which a plurality of transfer paper storage units (cassettes, paper mounting tables) are provided in a vertical direction. It relates to the device.

(Prior Art) Conventionally, in an image forming apparatus such as a copying machine, transfer sheets are accumulated in a cassette or a tray and stored in the image forming apparatus, and are fed into the machine one by one by a sheet feeding device in accordance with a transfer operation. To be done. In such an image forming apparatus, the size and type of the transfer paper must be changed depending on the size and type of the original.

In order to reduce this work as much as possible, usually 6 types of transfer papers, such as A3, B4, A4, A4R, B5, B5R, etc., are always stored in a cassette or tray, and any transfer is performed. There is provided a transfer paper supply device that selects paper only by operating switches without replacing cassettes or trays (R means lateral feed). In this case, for example, there is a method in which a plurality of cassettes are provided separately from the main body, a single sheet feeding device is provided, and the selected cassette is moved to a position facing the sheet feeding position of the sheet feeding device. In the case of (1), all the cassettes are moved, the device becomes large in size, the driving force becomes large, and the cost becomes high.

It is also known that a plurality of sheet feeding devices each including a sheet feeding roller group are provided corresponding to a plurality of trays or cassettes.

However, this drawback is that the number of sheet feeders is required for the number of types of transfer sheets, so that the cost is high, and the amount of stored sheets or the number of cassette stages is reduced by the amount occupied by the sheet feeders.

By the way, conventionally, in order to keep the paper feed pressure constant with respect to the decrease of paper by sequentially feeding out the top paper of the stacked paper, the change in the relative position between the top paper and the paper feed mechanism becomes almost constant, The paper table is raised by a lifting arm. However, when a plurality of trays are provided, this raising mechanism is also required, and the number of trays or cassettes is ultimately limited from the viewpoint of cost and space. Of course, the mechanism is also complicated.

This conventional example will be described with reference to FIG.

Now, assuming that the peripheral surface of the roller 1 is in pressure contact with the uppermost sheet loaded only by the weight of the roller and the supporting arm 2, the inclination θ of the supporting arm 2 of the roller 1 increases as the loading amount decreases. , Axis 3
Since the rotational power factor received from the paper of the supporting arm 2 supporting the roller 1 around the paper changes, the pressing force of the roller 1 on the paper changes (the pressing force of the paper feeding roller greatly affects the paper feeding performance. If the number is too small, the paper cannot be fed or the paper feed amount is insufficient, and if the amount is too much, the multi-sheet is fed.

In order to make the fluctuation of the feeding pressure due to the fluctuation of θ almost constant,
Conventionally, for example, as shown in the figure, a lifting arm 4 or the like is placed at the tip of the transfer paper placing table, and at this time, the arm 4 is interlocked with the increase or decrease of the transfer paper loading amount, and the transfer paper storage unit is moved vertically. Then, when a transfer mechanism is used, the relative position of the transfer sheet with respect to the sheet feeding device constituted by the roller 1, the supporting arm 2 and the like can be adjusted by the vertical movement of the transfer sheet storage section regardless of the amount of the load. The paper feed pressure and the paper feed path are controlled so as to be constant. In the transfer paper supply device having the above-mentioned six kinds of transfer paper storage parts, if each of the transfer paper storage parts is equipped with a device such as the arm 4 which moves up and down, the arm 4 etc. is provided in each transfer paper storage part. Drive source is required, which is complicated in terms of mechanism and control, and the cost is high. In addition, a space such as an arm is required for each transfer paper storage unit, and the space between the transfer paper storage units must be increased by that amount, resulting in an increase in the size of the entire apparatus.

(Purpose) In order to eliminate the above-described problems of the conventional example, the present invention uses a single sheet feeding device that is movable, and a plurality of transfer sheet storage units (trays).
The purpose is to move the paper feeding device to the selected transfer paper storage unit and feed and convey the paper.

(Structure) Hereinafter, the structure of the present invention will be described based on the illustrated embodiments.

FIG. 2 is an explanatory view showing a paper feed pressure adjusting mechanism according to the present invention. Reference numeral 7 is a paper feed device, and the call roller 16 is placed on the uppermost paper of the transfer paper stack P on the tray 11 by its own weight. There is.

The sheet feeding device 7 is movable in the vertical direction. As a means for keeping the sheet feeding pressure constant, the entire sheet feeding device 7 descends as shown by the arrow in FIG. In addition, the relative position between the uppermost paper and the paper feeding device 7 is kept constant. Thus, even if a plurality of transfer paper storage units are provided, a mechanism for moving each transfer paper storage unit up and down by a lifting arm or the like is unnecessary, and therefore, the drive source is only the vertical movement drive of the paper feeding device. Does not become complicated and saves space,
An inexpensive device can be provided.

FIG. 3 is a side view showing the entire transfer paper supply device 6 according to the present invention.

This is an example in which the copying machine main body 5 and the transfer paper supply device 6 are used as separate bodies in combination.

In the embodiment, the transfer paper supply device 6 is provided with six trays 11 and can store six kinds of transfer papers P. The tray 11 is engaged by a cam 13 on the tray receiver 12 so as to be movable in the CD direction in the figure, and the tray receiver 12 is mounted on the main body frame of the transfer paper feeding device 6 via the rail member 14. In the figure, it is engaged so that it can be pulled out in the front direction.

The cam 13 is selectively driven by a clutch not shown in the drawing. The sheet feeding device 7 is vertically movably engaged with the main body frame via a guide member, and the motor 9 drives the wire 8
Move up and down through.

When the paper is jammed or the like, the paper feeding device 7 is opened together with the conveyance path as shown by the alternate long and short dash line with B as a fulcrum, whereby the transfer paper inside the machine can be removed.

Next, details of the sheet feeding device 7 in this embodiment will be described.

FIG. 4 is a schematic side view of the paper feed / transport unit.

The sheet feeding device 7 is composed of a calling roller 16, a driving roller 17, a separation roller 18, rollers of a pair of conveying rollers 19 and 20, a guide plate 15, an arm 21 side plate 22, and the like through a guide member not shown in the drawing. , Is engaged with the main body frame so as to be vertically movable, and is vertically moved by a motor 9 via a wire 8.

The fed transfer paper P is turned around at the same time as being separated in the paper feeding device 7, and is transported by the transport belt 10.
In the embodiment, the separation roller 18 is shown, but in addition,
A friction pad system or the like is also conceivable.

FIG. 5 is a partially enlarged perspective view of the paper feeding device 7 described above.

In order to support the drive roller 17 and the transport roller 20,
A side plate 22 is provided, and the sensor 2 is mounted on the guide plate.
3 is provided. On the other hand, the calling roller 16 and the driving roller 1
A shield plate 24 is provided on the arm 21 between the sensors 7 and 7 and is combined with the sensor 23. As shown in the figure, the arm 21 is rotatable about the axis of the drive roller 17 within a certain angle range θ, and the calling roller 16 is the weight of the arm 21.
Also, the uppermost paper is in contact with the additional weight or the torque generated by the spring.

Then, in order to make the paper feeding pressure constant, the arm 21 is controlled so as to exist within a constant angular range θ ₁ (θ ₁ <θ) at the time of paper feeding.

Next, the operation of this embodiment will be described.

Tray 1 selected by operating switch (not shown)
The sheet feeding device 7 moves to 1 (transfer sheet storage section) and starts sheet feeding. As the number of transfer sheets decreases, the calling roller 16 in contact with the uppermost sheet, the arm 21 and the shielding plate 24 attached thereto gradually rotate downward. However, arm 2 up to a certain amount, that is, out of the θ ₁ range
When 1 rotates, the light or magnetic line of force in the sensor 23, which was blocked by the shield plate 24 this time, is released by the rotation of the shield plate 24, and the wire 8 or the like is released by the electrical signal accompanying the release. A command for lowering the entire sheet feeding device 7 works via the above. As a result, the relative position of the sheet feeding device 7 with respect to the tray 11 is lowered, the arm 21 exists in the θ ₁ range, and the arm 21 rotates upward to a position where the shield plate 24 blocks the inside of the sensor 23. To do.

By repeating the above operation, the arm 21 can be controlled to be within the constant angle range θ ₁ regardless of the number of transfer sheets, that is, the sheet feeding pressure can be maintained within the constant range. . Here, if the vertical movement driving source for maintaining the relative position of the paper feeding device 7 and the vertical movement driving source for paper selection are the same, a space saving is not required so that a low cost paper feeding device can be realized.

In this embodiment described above, the sensor 23 has been described as a photo interrupt sensor using light or a sensor using magnetic force, but in addition to this, a mechanical switch is provided on the side plate 22,
It can also be controlled by providing the arm 21 with a member for pushing the actuator.

(Effects) The present invention is as described above, and according to the present invention, since the single sheet feeding device is movable with respect to a plurality of transfer sheet storage portions, the sheet feeding device is configured to feed each of the conventional storage portions. The device equipped with the device has increased the size in the height direction and increased the cost due to the increase in the number of storage steps, but the space and cost are very small, and more storage units than the conventional ones. Can be provided. Further, compared to moving the entire transfer paper storage unit, it requires less space and driving force. Furthermore, compared to the mechanism that moves each transfer paper storage unit up and down to keep the paper feeding pressure constant, the paper feeding pressure can be kept constant by the vertical movement of only the paper feeding device, which saves space and cost. There is also an effect that it can be completed.

[Brief description of drawings]

FIG. 1 is a simplified side view showing a paper feed pressure adjusting mechanism according to a conventional example, FIG. 2 is a simplified side view showing a paper feed pressure adjusting mechanism according to the present invention, and FIG. 3 is related to one embodiment of the present invention. FIG. 4 is a side view showing the entire transfer paper feeding device, FIG. 4 is a side view of a main portion thereof, and FIG. 5 is an external perspective view of the same. 7: paper feeding device, 11: transfer paper storage (tray), 1
6 ... Calling roller, 17 ... Drive roller, 18 ...
Separation roller.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-161842 (JP, A) JPK 57-48835 (JP, Y2) JPK 58-3792 (JP, Y2)

Claims (2)

[Claims] 1. A transfer sheet feeding device for a copying machine, in which a plurality of transfer sheet accommodating sections are stacked substantially horizontally, wherein the transfer sheet accommodating section is provided at a position facing a front end of the transfer sheet accommodating section group in the transfer sheet conveying direction. A sheet feeding device including at least rollers that sequentially feed the transfer paper stored in the paper storage unit from the uppermost sheet; and moving the paper feeding device up and down in a direction substantially perpendicular to the installation direction of the transfer paper storage unit, A sheet feeding device moving unit that is positioned at one selected transfer sheet storage unit position; and the sheet feeding device moving unit is lowered as the number of sheets stacked in the transfer sheet storage unit decreases so that the stacked sheet Control means for controlling the paper feeding device moving means so as to keep the relative position to the uppermost paper substantially constant; transfer paper storage portion moving means for moving the transfer paper storage portion to the paper feeding device side; It should be almost perpendicular to the transfer paper transport direction in the paper storage section. Transfer sheet supply apparatus characterized by comprising a transfer sheet accommodating portion movable means to allow movement of the direction. 2. The roller according to claim 1, wherein the roller is swung via an arm, and the relative position of the sheet feeding device is controlled by detecting an angle change of the swung arm. A transfer paper supply device characterized by: