JPH0717282B2 - Cassette mounting device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cassette mounting device, and more particularly to a cassette mounting device for mounting a cassette on a sheet feeding portion of an image forming apparatus such as a copying machine.

[Conventional technology]

As shown in FIG. 6, the copy paper 10 stored in the cassette 8 is stacked on the intermediate plate 9. When the cassette guide (not shown) is attached to the main body, the lever 1 which is constantly pulled upward by the spring 3 at a position facing both sides of the cassette 8 is moved by the cams c on both sides of the cassette 8. Once pushed down to the bottom of the cassette 8. Thereafter, as shown in FIG. 7, the lever 1 is again pulled upward by the spring 3. Since the lever 1 and the pressure plate 2 are fixed to the shaft 5, the pressure plate 2 moves together with the lever 1. That is, when the lever 1 moves up and down by the cams c on both sides of the cassette 8, the lever 1 always moves up and down. Therefore, when the lever 1 is pulled upward beyond the cam c of the cassette 8, the pressure plate 2 also rotates upward (counterclockwise in the illustrated example). As a result, the intermediate plate 9 is lifted and the copy paper 10 on the intermediate plate 9 is pressed against the paper feed roller 7.

With such a structure, when the cassette 8 is taken in and out,
The lever 1 will always move up and down. Therefore, at this time, as the copy paper 10 decreases, the middle plate 9 rotates clockwise in the illustrated example, and approaches the paper feed roller 7. for that reason,
When the copy paper 10 is used up and the cassette 8 is pulled out for replenishment, the lever 1 moves to the cam c as shown in FIG.
Since it is located at the top of the, it requires considerable force when pulling out. That is, when the cassette was originally to be pulled out, it would be most difficult to pull out the cassette, which was a drawback. Lever 1 and pressure plate 2
This is because it increases as the copy paper 10 decreases.

[Object of the Invention]

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a cassette mounting device that facilitates mounting of the cassette.

[Means for solving problems]

In order to achieve the above object, a cassette mounting apparatus according to the present invention is a cassette mounting apparatus for mounting a cassette containing a sheet material in a sheet feeding section of an image forming apparatus including a sheet feeding unit for feeding a sheet material. A rotating member that rotates in response to an inserting operation of the cassette into the paper feeding unit, and the rotating member that is connected to the rotating member via an elastic member, and the cassette is interlocked with the rotation of the rotating member. A pressurizing member that lifts a sheet material inside and presses the sheet material against the sheet feeding means by the elastic force of the elastic member; and a sheet material provided on the rotating member and presses the sheet material by the elastic member onto the sheet feeding means. An engaging portion for engaging the cassette by a reaction force of the force to lock the cassette to the paper feeding portion.

[Action]

When the cassette is mounted, the rotating member rotates, and the pressing member presses the sheet material against the sheet feeding means via the elastic member. At this time, the rotating member engages with the cassette by the reaction force of the pressure contact force of the pressure member, and regulates the movement of the cassette. As a result, both the pressing operation of the sheet material and the paper feeding means and the locking operation of the cassette are performed in conjunction with the operation of pushing the cassette into the paper feeding unit.

Further, if the force for pressing the sheet material to the sheet feeding means by the pressing member is set to be substantially constant, the reaction force of the pressing force causes the engaging portion to engage with the cassette, so that the sheet material is loaded. It can be pulled out with almost constant force regardless of the amount.

〔Example〕

 Hereinafter, the present invention will be described based on the illustrated embodiments.

FIGS. 1 to 3 show an embodiment of the present invention, in which a lever 11 as a rotating member moves up and down by the cam surfaces on both sides of the cassette when the cassette is attached or detached. Reference numeral 12 is a pressure plate as a pressure member for pressing the intermediate plate 9, and is not directly fixed to the shaft 15. 13 is a pressure spring as an elastic member for pressing the pressure plate, 14 is a stopper on the shaft 15 that abuts against the pressure plate 12, 15 is a shaft fixed to the lever 11, and the pressure spring
It also serves as a rotation axis of the pressure plate 13 and the pressure plate 12. 16 is a shaft support plate that supports the shaft 15, 17 is a paper feed roller that constitutes a paper feed unit for feeding copy paper in the cassette 18, 18 is a cassette that stores copy paper, and 19 is a plate 12 The intermediate plate is pressed by the sheet feeding roller 17 so as to press the copy sheet against the sheet feeding roller 17, 10 is the copying sheet fed by the sheet feeding roller 17, and 20 is the sheet feeding roller 17 with the leading edge of the sheet smooth when the cassette is inserted. It is a guide roller that goes under.

The lever 11 and the shaft 15 move one-to-one (integrally). Pressure spring
One end of 13 is fixed to the shaft 15, and the other end of the spring 13 is applied to the pressure plate 12, and the pressure is applied in the direction of pushing up the pressure plate 12 (counterclockwise in the illustrated example). However,
The shaft 15 has a stopper 14 and the pressure plate has a stopper 14.
Since the pressure plate 12 is always pressed by the pressure spring 13, the lever 11 and the pressure plate 12 are stopped at a certain angle.

That is, when no force is applied to the lever 11 and the pressure plate 12 from the outside, the lever 11 and the pressure plate 12 rotate right by their own weight while maintaining a constant angle. This right rotation is suppressed by the lever 11 contacting the bent portion 16a of the shaft support plate 16. This state is shown in Fig. 1,
It is shown in FIG.

Here, as shown in FIG. 2, when the cassette 18 is inserted along a cassette guide (not shown), the end 11a is inserted into the cassette 1.
The lever 11 rotates (counterclockwise in the illustrated example) along the cam surfaces 21 on both sides of 8, and the pressure plate 12 that is pressed by the pressure spring 13 whose one end is fixed to the shaft 15 is also pressed. Rotate. The portion of the cassette 18 where the pressure plate 12 is located is cut out, and the pressure plate 12 directly pushes up the middle plate 19 when it rotates. Copy paper 10 is stacked on the middle plate 19,
At a certain position, the copy paper 10 contacts the paper feed roller 17 while being guided by the guide roller 20. Due to this contact, the pressure plate 12 is stopped, but the lever 11 is rotated along the cam surfaces 21 on both sides of the cassette as it is (at this time, the pressure spring 13 is further charged), and the cassette 18 is not shown. When it hits the par, the lever 11 is lifted to the upper end of the cassette 18. Then, the lever 11 falls into the recess 21a at the tip of the cassette to fix the cassette. Pressure plate 12
Since the counterclockwise force acts on the copy paper 10 via the pressure spring 13, the copy paper 10 is pressed against the paper feed roller 17 with a certain force.
Here, the pressure contact force is the angle between the lever 11 and the pressure plate 12 and the middle plate 19
The pressure spring 13 is designed to be substantially constant in consideration of the relationship of the amount of the copy paper 10 loaded. This hollow 21a
Together with the lever form the locking means of the cassette.

Therefore, when removing the cassette 18, it is necessary to remove the lever 11 from the recess 21a at the tip of the cassette for fixing the cassette, but the force pressing the lever 11 against the cassette 18 is the pressure plate. It is a reaction force of the force by which the pressure spring 13 lifts 12 and this force is almost constant regardless of the amount of paper. At that time, the amount of movement of the lever 11 to escape from the recess 21a may be small, and is constant regardless of the amount of copy paper 10. As a result, the force for pulling out the cassette 18 has no relation to the amount of the copy paper 10 and can be pulled out with a substantially constant force. In particular, the lever 11 is always at the same position regardless of the position of the middle plate, and by setting this position to the position shown in the figure (upper end of the cassette), the lever 11 can be pulled out with a weaker force than that of the configuration of the conventional example.

The above is a description of one embodiment according to the present invention, but the present invention is not limited to this embodiment.

For example, in the present embodiment, the torsion coil spring is used as the pressure spring, but the tension spring 31 may be used as shown in FIG. That is, any shape may be used as long as the lever and the pressure plate are pulled together.

Further, in this embodiment, the lever and the shaft are fixed, the pressure plate is free with respect to the shaft, and the rotation of the shaft is transmitted to the pressure plate by the spring. As shown in FIG. Fixed,
The lever 41 and the shaft 45 may be made free, and the rotation of the lever 41 may be transmitted to the shaft 45 via the spring 43. 44 is a stopper.

Further, in the present embodiment, the guide 20 is an idler roller, but it may be a smooth fixed guide.

As described above, according to the embodiment of the present invention, since the lever for pressing is dropped into the recess of the cam on the side surface of the cassette, it is possible to easily press the paper at the same time by simply inserting the cassette. It is possible to fix it.

Further, since the pressure spring is pulled on one shaft to apply pressure, the assembly to the main body is completed simply by screwing the shaft support plate. Therefore, the assemblability is also improved.

By providing a stopper between the lever and the pressure plate and applying pressure to the pressure plate from the beginning, even with a slight rotation angle of the lever,
It was possible to keep the applied pressure constant.

Further, since the guide is provided on the upstream side of the paper feed roller, when the paper is lifted by the pressure plate (during loading), the leading edge of the paper does not hit the paper feed roller and jam, and then the cassette is further loaded. This makes it possible to smoothly press the paper feed roller into contact.

〔The invention's effect〕

The cassette mounting device according to the present invention interlocks with the operation of pushing the cassette into the paper feeding portion, and performs both the pressure contact operation of the sheet material and the paper feeding means and the locking operation of the cassette.
Operability is improved, and the burden on the user can be reduced. Further, since the cassette is locked by using the rotating member for moving the pressing member for lifting the sheet material, it is not necessary to provide a special member for locking, and the cost can be reduced.

In addition, since the engaging part engages the cassette by the reaction force of the pressure contact force and performs the locking operation, the cassette can be pulled out with a substantially constant force regardless of the stacking amount of the sheet material, and the pulling out operation is easy. Becomes

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a cassette mounting device and a cassette according to the present invention, FIGS. 2 to 3 are front views for explaining the operation, and FIGS. 4 to 5 are other embodiments. And FIG. 6 to FIG. 8 are front views showing a conventional example. 11,41… Lever 12,42… Pressure plate 13,31,43… Pressure spring 14,44… Stopper 18… Cassette 19… Middle plate 21… Cam 21a… Cavity

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-57-166236 (JP, A) JP-A-55-16821 (JP, A) JP-A-61-60535 (JP, A) Actual development Sho-56- 92633 (JP, U) Actual development Sho 59-133541 (JP, U) Japanese Patent Sho 61-31013 (JP, B2)

Claims (2)

[Claims] 1. A cassette mounting device for mounting a cassette containing a sheet material in a paper feeding portion of an image forming apparatus equipped with a paper feeding means for feeding a sheet material, comprising: A rotating member that rotates in response to an inserting operation, and the rotating member is connected via an elastic member, and the sheet material in the cassette is lifted by interlocking with the rotation of the rotating member to raise the elastic member. A pressing member that presses the sheet material against the sheet feeding means by an elastic force; and a reaction force of a force that is provided on the rotating member and presses the sheet material against the sheet feeding means by the elastic member, and engages with the cassette. And an engaging portion for locking the cassette to the paper feeding portion, and a cassette mounting device. 2. The lock portion is provided at an end portion of the rotating member, and locks when the engaging portion falls into a recess provided in the cassette. The cassette mounting device according to the item.