JPH0511232Y2 - - Google Patents

Description

[Detailed Description of the Invention] (A) Field of Industrial Application The present invention relates to a large-capacity paper feeding device that can store a large amount of paper and feed it one by one.

(B) Conventional technology In recent years, as image forming devices such as copying machines and printers have become faster, large-capacity paper feeders that can store a large amount of paper and feed it one sheet at a time have been developed in order to reduce the number of times paper needs to be replenished. Paper devices are becoming available. Such a large-capacity paper feeding device includes a paper storage section that can accommodate a large amount of paper by placing it on a paper mounting table, and a state in which the paper mounting table can be switched between a state in which paper can be fed and a state in which paper can be replenished. The apparatus is equipped with a paper mounting table driving means that can drive the paper table, and a paper feeding means that transports the paper from the paper storage section to the downstream side of the apparatus.

Then, a large amount of paper is placed on the paper loading table that is ready for paper replenishment, the sheet loading table driving means switches the sheet replenishing condition to the paper feeding possible condition, and then the sheet feeding means The paper is conveyed from the paper storage section to the downstream side of the apparatus, and the paper is always kept on standby so that it can be fed into the main body of the image forming apparatus in response to a copy signal from a copy operation.

(C) Problems that the invention aims to solve However, conventional large-capacity paper feeders are designed to accommodate A4 or B5 size paper, which is the most frequently used size. From the beginning, we did not plan to store such large-sized paper. However, some users desire to use B4 or A3 size paper by loading it into a large capacity paper feeder. Therefore, from the beginning, B4 or
It may be possible to design the paper assuming that it will store A3 large size paper, but such size paper is used less frequently, and even if the same number of sheets are stored, the larger size will increase the storage volume and weight. Since the paper is heavy, it is necessary to provide a paper mounting table driving means that can withstand the high load when large-sized paper is placed, which results in problems such as high cost and high power consumption.

Therefore, the present invention provides a large-capacity paper feeding device that uses a conventional paper loading table driving means with relatively low torque, and provides a space large enough to load and store large-sized paper, and also provides storage space for large-sized paper. It is an object of the present invention to provide a large-capacity paper feeding device that prevents a load exceeding an allowable range from being applied to a paper mounting table driving means by making it possible to limit the amount of paper loaded.

(D) Means for solving the problem The present invention provides a paper storage unit that can accommodate a large amount of paper by placing it on a paper loading table, and a state in which the paper loading table is in a state where paper can be fed and paper can be replenished. In a large-capacity paper feeding device that is equipped with a paper mounting table driving means that can be switched to a paper mounting table state and a paper feeding means that transports paper from a paper storage section to the downstream side of the apparatus, a large-sized sheet is placed on the paper mounting table. A large-capacity paper feeder characterized by having a removable auxiliary stand that has a space for placing paper and a height that limits the paper storage amount to a range that does not exceed the paper storage limit. It is.

(E) Effect Since a space is provided in the paper storage section in which large-sized paper can be placed and stored, even large-sized paper can be placed therein, and by the limiting means,
To prevent high loads from being applied to the paper loading table drive means,
The amount of paper stored is limited to a range that does not exceed the storage limit. Therefore, since only a load within the permissible range is applied to the paper loading table driving means, the drive for switching from the position where paper can be replenished to the position where paper can be fed is performed smoothly, and after that, the paper loading table is stopped. The paper is transported from the paper storage section to the downstream side of the apparatus by the transport means.

(F) Example Next, regarding the large capacity paper feeder according to the present invention,
A more detailed explanation will be given with reference to the drawings.

Referring to FIG. 3, a large-capacity paper feeding device, generally indicated by 6, has a paper storage section 11 and a paper storage section 11 that protrudes above the paper storage section 11 and is inserted into a cassette opening (not shown) to feed images of a copying machine or the like. It consists of a connecting part 25 that is connected to the forming device.

The paper storage section 11 includes a paper mounting table 12 on which the paper P is placed, and a paper mounting table driving means 13 that can switch the paper mounting table 12 between a state in which paper can be fed and a state in which paper can be replenished. is provided. The paper storage section 11 is provided with a space in which large-sized paper such as B4 and A3 can be placed and stored. Therefore, it is necessary that the surface on which the paper is placed has the same area as the large size paper, but this is necessary for both the paper placement table 12 and the paper placement surface 2 of the auxiliary table 1, which will be described later. Also, or
This is achieved because only the paper placement surface 2 of the auxiliary stand 1 has an area for large-sized paper.

To explain in more detail the paper mounting table driving means 13, the paper mounting table driving means 13 includes a forward/reverse motor 14, a drive transmission gear 15 meshing with the output shaft 14a of the forward/reverse motor, and a drive transmission gear 15.
The drive sprocket 16 is coaxial with a drive gear meshing with the drive gear, and drive sprockets 17, 18, 19 are driven from the drive sprocket 16 via a drive chain 20. Drive sprockets 18 and 19 are mounted coaxially and are driven to rotate in the same direction. One end 20a of the drive chain 20 is fixed at the upper right part of the paper storage section 11 in the drawing, and is wound around the drive sprocket 17 via the drive sprocket 18, and further connected to the drive sprocket 19 via the drive sprocket 16.
The other end 20b is fixed to the lower right portion of the paper storage section 11 in the figure. Since a driving sprocket 18 is attached to the paper mounting table 12, the paper mounting table 12 moves up and down as the forward/reverse rotation motor 14 rotates.

At the upper part of the paper storage section 11, there is a paper mounting table 12.
is driven upward by the paper loading table driving means 13, and the paper P
A detection means 29 for detecting the upper surface of the paper P and a detection means 30 for detecting that the paper P is running out are provided. The detection means 29 and 30 are, for example, photo interrupter type detection means, and include actuators 29a and 30a and shielding plates 29b and 30b.
and optical sensors 29c and 30c. Then, the paper mounting table 12 is driven upward by the paper mounting table driving means 13, and the upper surface of the paper P is detected by the detection means 29.
When the actuator 29a contacts the actuator 29a and rotates clockwise, the shielding plate 2
9b blocks the light emitted from the light emitter of the optical sensor 29c, and based on the signal, the rotational drive of the motor 14 is stopped. Even when the paper P is fed and the amount of paper decreases, the detection means 29 is configured so that the top surface of the paper always comes into contact with the paper feed roller 21, which will be described later.
The paper mounting table driving means 13 moves the paper mounting table 1 until the optical sensor 29c detects the shielding plate 29b.
2 is always driven upward and stopped. Also,
The detection means 30 is configured to insert an actuator 3 into a hole provided on the paper mounting table 12 when the paper P runs out.
0a fits into the shielding plate 30b and connects it to the optical sensor 3.
When 0c is no longer detected, it is determined that there is no paper.

Above the paper storage section 11 and the connecting section 25, a paper feed roller 21, a feed roller 22, and guide plates 23 and 24 for guiding the paper to be conveyed are further provided as paper feeding means. Further, a sensor 28 is provided on the downstream side of the feed roller 22, and a sensor 27 is provided on the downstream side of the guide plate 24. Furthermore, a connection detection means 26 is provided at the tip of the connection part 25.
is inserted into the cassette opening, the connection detection means 26 detects the connection, and based on the detection signal, the paper feed roller 21 is driven to rotate, transporting the paper P, and the leading edge of the paper P touches the feed roller 22. When the paper P reaches the paper P, the feed roller 22 is driven to rotate, and when the leading edge of the paper P is detected by the sensor 27, the feed roller 22 is stopped. Connecting part 2
5 is inserted into the cassette opening, the paper feed roller 39 provided on the main body side of the image forming apparatus faces the upper part of the connecting portion 25. Therefore, the paper P is always inserted into the paper feed roller 39. It is supplied so that it is in contact with the Then, when the paper feed roller 39 is rotationally driven based on the image formation start signal, the paper P enters the main body of the image forming apparatus, and accordingly, the rear end of the paper P separates from the sensor 28, and the sensor 28
It will be in the OFF state. Then, the paper feed roller 21 in the large-capacity paper feed device 6 starts rotating, and when the leading edge of the next paper P reaches the feed roller 22, the rotation is stopped. Then, when the rear end of the previous paper P leaves the sensor 27, the feed roller 22 rotates and the paper P is conveyed until it reaches the position of the sensor 27. Thereafter, the sheets are fed one by one in the same manner.

The upper surface of the paper storage section 11 has a rotatable lid 3.
1, and the upstream side of the paper storage section 11 is
It consists of a door 36 that can be opened and closed, and when replenishing paper P, by opening this door 36,
Paper can be replenished. Lid body 31 and door 3
6 are formed with protrusions 31a and 36a, respectively. When the lid body 31 is closed, the protrusion 31
A rotatable lever member 32 is provided at the position where a is in contact with the lever member 32, and an actuator 34a of the sensor 34 is provided at a position where it can be pressed by the tip of the lever member 32. Also, when the door 36 is closed, the door 3
A rotatable lever 35 is provided at a position where the protrusion 36a of No. 6 abuts, and a sensor 34 is fixed to the lever 35. And the sensor 34 is
It is set to be in the ON state only when the lid body 31 and door 36 are closed. and sensor 34
Based on the ON signal of
is controlled to drive the paper mounting table 12 upward in order to make it ready for paper feeding. Further, when the sensor 34 is in the OFF state, the paper mounting table 12 is
The paper mounting table driving means 13 drives the table downward to make it possible to replenish paper.

Note that casters 3 are provided at the bottom of the large-capacity paper feeder 6 to facilitate movement of the large-capacity paper feeder 6.
8 and 38, and an overturn prevention member 37 for preventing the large capacity feeding device 6 from overturning.

In the case of the above-mentioned large-capacity paper feeder 6, the motor 14
Since the torque is relatively small, if large-sized sheets are placed until the paper storage space in the height direction is exhausted, too much load will be applied to the sheet mounting table driving means 13. In the experiment, when motor 14 with a torque of 0.6 kgcm was used, A4 size paper was
The paper table 12 loaded with 2,500 sheets (approximately 10 kg) could be easily driven, but
2500 sheets (approximately 15 kg), 2500 sheets of A3 size paper (approximately 20
It was difficult to drive the paper table 12 on which the weight (kg) was placed.

Therefore, a limiting means is required to limit the amount of paper stored. Therefore, referring to FIG. 1, the limiting means according to the present invention will be described next. The restricting means 1 is composed of an auxiliary stand that can be detachably attached to the large-capacity paper feeder 6, and has a box shape having a paper placement surface 2, side surfaces 3, 4, and a bottom surface 5. .

The paper placement surface 2 is set to an area that allows large-sized paper to be stored. Therefore, even if the paper placement table 12 only has an area where a frequently used size of paper can be placed, it is possible to store and use large-sized paper by using the auxiliary table 1. Furthermore, a friction member 8 is provided on the upper surface of the paper placement surface 2 at a position downstream in the paper transport direction when the auxiliary table 1 is placed on the large-capacity paper feeder 6, for preventing double feeding of paper. Furthermore, a hole 7 is formed on the upper surface of the paper placement surface 2, and the paper P placed on the paper placement surface 2 is prevented from being pulled out.
When the paper runs out, the actuator 30a of the detection means 30 (see FIG. 3) fits into the hole 7, making it possible to detect that the paper has run out.

The height of the sides 3 and 4 is such that the auxiliary stand 1 is the same as the paper storage section 1.
1, the paper storage amount, that is, the weight, is set to a value that limits the storage limit amount. In the experiment,
When using auxiliary stand 1 with a height of 8.5 cm, the paper was
It can hold 1,500 sheets, and if it is B4 size paper, it will weigh about 9 kg. Since the weight of the auxiliary stand 1 was set to approximately 0.75 kg, the paper loading stand 12
The total weight of the apparatus could be suppressed to 9.75 kg, that is, approximately 10 kg, and the paper mounting table driving means 13 could be driven smoothly. As is clear from the above, it is desirable that the weight of the auxiliary table 1 be as light as possible in order to reduce the load on the sheet loading table driving means 13.

Further, the bottom surface 5 is provided with a locking piece 9 on the downstream side and a locking piece 10 in the middle, so that the auxiliary table 1 can be locked on the paper mounting table 12. When the auxiliary stand 1 is used as a limiting means in this manner, the load applied to the paper mounting stand driving means 13 can be kept within an allowable range with a relatively simple configuration.

FIG. 2 is a perspective view showing a state in which the door 36 of the large-capacity paper feeder 6 is opened. In addition, the protrusion 36 of the door 36
Regarding a, it is omitted for convenience. In the paper storage section 11, the paper mounting table 12 is in a state where paper can be supplied, and the paper mounting table 12 is provided with a plurality of long grooves 40, and a size regulating plate 41 is fitted into the long grooves 40. There is. The auxiliary stand 1 is mounted by being placed on the paper mounting stand 12, as shown by the two-dot chain line. At this time, the locking piece 10
is engaged with the long groove 40, and the locking piece 9 is engaged with the downstream end of the paper mounting table 12, so that the auxiliary table 1 can be placed in a predetermined position. The locking piece 10 is
The door 36 side contacts the rear end of the long groove 40,
The auxiliary stand 1 is prevented from leaning toward the door 36 side,
The friction member 8 provided on the auxiliary stand 1 is configured to be in a position facing the paper feed roller 21 in a state where paper can be fed. The locking piece 9 prevents the auxiliary stand 1 from being placed on the paper loading table 12 in a biased manner toward the upstream side of the paper storage section 11, and prevents the auxiliary stand 1 from coming into contact with the front wall of the paper storage section 11. It allows you to move up and down without any movement.

Next, the operation of the large capacity paper feeder 6 according to the present invention will be described.

First, when replenishing large size paper P, open door 3.
Open 6. Then, the protrusion 36a is separated from the lever 35, and as the lever 35 rotates, the sensor 34 is turned off, and the sensor 34 is turned off.
Based on the signal, the forward/reverse rotation motor 14 of the paper mounting table driving means 13 is reversely rotated. Then, paper loading table 1
2 moves downward and shifts from a state in which paper feeding is possible to a state in which paper replenishment is possible. And paper mounting table 1
2 is completely lowered, the size regulating plate 41 is set according to the size of the paper, and furthermore, the auxiliary stand 1 serving as the paper storage amount limiting means is placed on the paper mounting table 12. Then, a large size paper P is placed on the paper placement surface 2 of this auxiliary stand 1. At this time, paper P
The amount of paper that can be accommodated in the paper storage section 11 is limited by the height of the auxiliary table 1. Therefore, the amount of paper that can be stored can be suppressed below the limit amount. There is no risk of high load being applied.

When the door 36 is closed after placing the paper, the sensor 3
4 is turned on, and the forward/reverse rotation motor 14 of the paper mounting table driving means 13 is rotated in the normal direction. The paper mounting table driving means 13 is driven until the upper part of the paper P is detected by the sensor 29, and the state shifts to a state where the paper can be fed. Thereafter, when the large-capacity paper feeding device 6 is attached to the image forming apparatus, the connection detection means 26 detects the connection, and the paper feeding roller 21 is rotationally driven. The paper P is guided to the feed roller 22 by the guide plate 23, and is conveyed by the rotation of the feed roller 22 until the leading edge of the paper P is detected by the sensor 27, and then the paper P is stopped. Then, so that paper can be fed in accordance with the image formation start signal,
Leave the paper waiting.

When using a relatively small size paper that is frequently used, such as A4 or B5, the paper P is placed directly on the paper mounting table 12 without using the auxiliary table 1.

Although the above embodiment has been explained using experimental data, the experimental data includes the number of sheets of paper to be placed, the weight of the paper mounting table 12 and the auxiliary table 1, and the transfer from the motor 14 to the paper placing table 12. It goes without saying that it is not limited to the above experimental data since it varies depending on the loss of drive torque during the process of transmitting the drive.

(G) Effect of the invention As described above, the large-capacity paper feeding device according to the invention includes a limiting means for limiting the amount of paper stored within a range that does not exceed the storage limit when large-sized paper is stored in the paper storage section. , it is possible to prevent loads exceeding the permissible range from being applied to the paper loading table driving means, and it is possible to provide a low-cost, large-capacity paper feeding device with low power consumption, which is a unique practical feature. It has the desired effect.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view showing a limiting means applied to the large-capacity paper feeder according to the present invention, Fig. 2 is a perspective view showing the state in which the limiting means is placed on the large-capacity paper feeder, and Fig. 3 is a cross-sectional view of the large-capacity paper feeder according to the present invention. 1: limiting means (auxiliary stand), 6: large-capacity paper feeder, 11: paper storage section, 12: paper placement stand, 13: paper placement stand driving means, 21, 22:
...Paper feeding means.

Claims (1)

[Scope of Utility Model Registration Claim] A paper storage unit that can accommodate a large amount of paper by placing it on a paper stack, and the paper stack can be switched between a state where paper can be fed and a state where paper can be replenished. In a large-capacity paper feeding device equipped with a paper mounting table driving means and a paper feeding means for transporting paper from a paper storage section to the downstream side of the apparatus, a large-sized paper is placed on the paper mounting table. 1. A large-capacity paper feeding device characterized by having a removable auxiliary stand that has a space for storing paper and a height that limits the amount of paper stored within a range that does not exceed the storage limit of paper.