JPH10329958A - Paper feeding cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeding cassette in which shock noise can be reduced when a proper braking force is applied to a bottom plate lowering by its self-weight. SOLUTION: When a paper feeding cassette 6 is pulled out from a copying device for supplying recording paper 9, connection between a fixed driving shaft 11 in a lifting lever 10 lifting a bottom plate 8 and a joint part for a lifting motor is released, so that the bottom plate 8 starts to turn downward because of its self-weight. The bottom plate 8 starting to lower is brought into contact with a spring 17, which is arranged on the front end side of a bottom face 7a, and the lowering speed of the bottom plate 8 is suppressed. Therefore, the spring 17 applies a proper braking force to the bottom plate 8 lowering by its self-weight, and as a result, a shock noise due to a collision between the bottom plate 8 and the bottom face 7a in a main body case 7 can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed cassette, and more particularly, to reducing the impact noise between the bottom surface of the main body case and the bottom plate when the bottom plate on which the paper is placed is lowered by its own weight in the main body case. Paper cassette.

[0002]

2. Description of the Related Art In an image forming apparatus such as a facsimile machine, a copying machine, and a printer, a plurality of sheets (recording sheets) are stored in a sheet cassette, and sheets are fed one by one from a sheet cassette by a sheet feeding roller. It is sent out and recorded.

In this paper feed cassette, in particular, in a paper feeder in which paper to be stored is separated from the uppermost paper by a paper feed roller one by one and fed, a bottom plate for pushing up the recording paper into the paper feed cassette and a bottom plate A lifting mechanism is provided to raise the bottom plate upward, and the recording paper is brought into contact with the paper feed roller by the bottom plate which is raised upward by the raising mechanism, and the uppermost recording paper is sent out one by one by the paper feed roller. I have.

[0004] Such a paper feed cassette is pulled out from an image forming apparatus such as a printer when replenishing paper, or the like. When pulling out the paper feed cassette from the image forming apparatus, the paper feed roller and the bottom plate or the bottom plate are removed. In order to prevent the recording sheets from interfering with each other and to facilitate the supply of the recording sheets to the sheet cassette, when the sheet cassette is pulled out from the image forming apparatus, the bottom plate is raised by the lifting mechanism. The force is released and the bottom plate descends by its own weight.

However, in the conventional paper cassette, the bottom plate simply descends by its own weight. When the bottom plate descends to the bottom surface of the paper cassette, the bottom surface of the paper cassette main body collides with the bottom plate. There was a problem that sound was generated. The impact noise varies depending on the number of sheets that can be placed in the sheet cassette and the number of sheets placed on the bottom plate when the sheet cassette is pulled out. Among the sheet cassettes that can be stored, a sheet cassette that can store 500 sheets has a higher impact sound, and the smaller the number of sheets already placed, the larger the sound. That is, the larger the distance between the bottom surface and the bottom plate of the paper feed cassette main body (the higher the height of the bottom plate), the higher the impact noise tends to be.

In view of the above, conventionally, there has been proposed a sheet placing apparatus which reduces the impact noise caused by the sheet placing plate colliding with the bottom surface of the sheet conveying device which is the main body case when the sheet placing plate as the bottom plate is lowered. (Japanese Unexamined Patent Publication No. 8-1274)
No. 34).

In this sheet mounting apparatus, a sheet mounting plate is lifted by a wire rope, and the wire rope is wound around a winding winch fixed to a winding shaft. Then, rotate this take-up winch, take up and rewind the wire rope, raise and lower the sheet mounting plate, connect the brake damper to the take-up shaft, cut off the brake damper, and An oil damper that is sequentially connected in accordance with the rotation of the toothless gear is used to apply a braking force to the lowering of the sheet mounting plate by using the oil damper to reduce the impact noise.

[0008]

However, in such a conventional paper feed cassette, a brake damper having a toothless gear and an oil damper is used to apply a braking force to the lowering of the bottom plate due to its own weight. In order to apply an appropriate braking force to the lowering of the bottom plate due to its own weight, a plurality of oil dampers must be used, resulting in a problem that the mechanism becomes large and the cost increases.

Therefore, the invention according to claim 1 is characterized in that the bottom plate acts between the bottom surface of the main body case of the sheet cassette and the bottom surface of the bottom plate descending by its own weight in the main body case and acts on the bottom surface side of the bottom plate. By arranging a predetermined elastic member that suppresses the descent speed, a simple and small mechanism applies an appropriate braking force to the descent caused by the weight of the bottom plate, and reduces the impact noise caused by the impact between the bottom plate and the bottom surface of the main body case. It is an object of the present invention to provide a sheet cassette that can be appropriately and inexpensively reduced.

According to a second aspect of the present invention, as the elastic member,
By using a spring, with a smaller and simpler mechanism, a proper braking force is applied to the lowering of the bottom plate due to its own weight, and the impact sound due to the impact between the bottom plate and the bottom of the main body case is more appropriate. It is another object of the present invention to provide a paper cassette which can be reduced at a low cost.

According to a third aspect of the present invention, the bottom plate acts between the side surface of the bottom plate and the side surface of the main case of the paper feed cassette in which the bottom plate descends by its own weight to reduce the lowering speed of the bottom plate. By arranging a predetermined friction member that suppresses, a simple and small mechanism applies an appropriate braking force to the descent due to the weight of the bottom plate, and the impulsive sound due to the impact between the bottom plate and the bottom surface of the main body case is appropriately reduced. It is another object of the present invention to provide a sheet cassette which can be reduced at a low cost.

[0012]

According to a first aspect of the present invention, a bottom plate on which a plurality of sheets are placed is raised in a main body case by a lifting force applied from a predetermined lifting mechanism. When the sheets placed on the bottom plate are separated and conveyed one by one by a feed roller and the lifting force of the bottom plate by the lifting mechanism is released, the bottom plate weighs itself within the main body case. A predetermined elastic member that acts on the bottom surface side of the bottom plate to suppress the lowering speed of the bottom plate is disposed between the bottom surface of the main body case and the bottom surface of the bottom plate. By having
The above objective has been achieved.

According to the above construction, the bottom plate acts on the bottom surface of the bottom plate between the bottom surface of the main case and the bottom surface of the bottom plate of the paper feed cassette in which the bottom plate descends by its own weight, thereby suppressing the lowering speed of the bottom plate. Since a predetermined elastic member is arranged,
An appropriate braking force can be applied to the lowering of the bottom plate due to its own weight by a simple and small mechanism, and the impact noise caused by the impact between the bottom plate and the bottom surface of the main body case can be appropriately reduced at low cost.

In this case, for example, the elastic member may be a spring.

According to the above configuration, since the spring is used as the elastic member, an appropriate braking force can be applied to the lowering of the bottom plate due to its own weight with an even smaller and simpler mechanism. The impact sound caused by the impact between the bottom plate and the bottom surface of the main body case can be more appropriately and inexpensively reduced.

According to a third aspect of the present invention, the bottom plate on which a plurality of sheets are placed rises in the main body case by a lifting force applied from a predetermined lifting mechanism, and is moved by a paper feeding roller. A sheet cassette in which the sheets placed on the bottom plate are separated and conveyed one by one, and when the lifting force of the bottom plate by the lifting mechanism is released, the bottom plate descends in the main body case by its own weight. A predetermined friction member that acts on a side surface of the bottom plate and suppresses a lowering speed of the bottom plate is provided between a side surface of the main body case and a side surface of the bottom plate. Have achieved.

According to the above configuration, the bottom plate acts on the side surface of the bottom plate between the side surface of the main case and the side surface of the bottom plate of the sheet cassette where the bottom plate descends by its own weight, thereby suppressing the lowering speed of the bottom plate. Since a predetermined friction member is provided, it is possible to apply an appropriate braking force to the descent by the weight of the bottom plate by a simple and small-sized mechanism, and to appropriately apply the impact sound due to the impact between the bottom plate and the bottom of the main body case And can be reduced at low cost.

[0018]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 3 show a first embodiment of a paper feed cassette according to the present invention, and this embodiment is applied to a paper feed cassette of a copying apparatus.

FIG. 1 is an overall perspective view of a copying apparatus 1 to which a first embodiment of a paper feed cassette according to the present invention is applied. In FIG. 1, a copying machine 1 has a document table 2 and a document discharge table 3 provided with an ADF (automatic document feeder) on the upper part, an operation display section 4 on the front upper part, and a recording paper on the side. A paper discharge tray 5 is provided, and a paper feed cassette 6 is detachably attached to a lower part of the front by pulling out and pushing the paper drawer forward as shown by arrows Fa and Fb.

As shown in FIG. 2, the paper feed cassette 6 has a bottom plate 8 housed in a substantially rectangular main body case 7.
A plurality of recording papers 9 are placed on the bottom plate 8. The bottom plate 8
As shown in FIG. 3, a pair of hinge portions 8a and 8b which are bent upward at both end portions are provided.
8b, it is rotatably attached to the side wall of the main body case 7.

On the bottom surface 7a of the main body case 7 below the bottom plate 8, a lifting lever 10 is provided.
Is fixed to the tip of the drive shaft 11. Drive shaft 11
As shown in FIG. 3, a drive pin 12 extending in a direction perpendicular to the drive shaft 11 is fixed to a base end of the drive pin 12. Linked to

When the paper feed cassette 6 is pulled out of the copying apparatus 1, it is pulled out in the direction of arrow Fa shown in FIG. 3, and at this time, the connection between the drive pin 12 and the connection portion 14 of the lifting motor 13 is released. The paper cassette 6 is
When mounted on the copying apparatus 1, the arrow Fb shown in FIG.
, And at this time, the drive pin 12 and the connecting portion 14 of the lifting motor 13 are connected.

The ascending motor 13 is driven to rotate in a state where the drive pin 12 is connected to the connecting portion 14, to drive the drive pin 12, and to rotate the drive shaft 11 to which the drive pin 12 is fixed. When the drive shaft 11 is rotationally driven, the drive shaft 1
The lifting lever 10 fixed to 1 is rotated clockwise in FIG.

As described above, the lifting lever 10 is connected to the bottom plate 8.
When the ascending motor 13 rotates clockwise in FIG. 2, the bottom plate 8 is connected to the hinge portions 8 a and 8.
The free end of the bottom plate 8 is turned around the center b in the direction of moving the free end upward.

The lifting lever 10, the driving shaft 11, the driving pin 12, the lifting motor 13 and the connecting portion 14 function as a lifting mechanism.

A pair of claw members 15 a and 15 b are provided at both ends of the upper end of the main body case 7 of the paper feed cassette 6 (left side in FIG. 2), and are mounted on the bottom plate 8. When the bottom plate 8 is rotated upward by the rotation of the lifting lever 10, the leading end of the recording paper 9 rises in accordance with the rotation of the bottom plate 8, and both sides of the leading end of the recording paper 9 are moved. The ends engage the claw members 15a, 15b. Claw members 15a, 15b
Engages both ends of the recording paper 9 to separate the recording paper 9 one by one.

In the storage section of the sheet feeding cassette 6 of the copying apparatus 1, a sheet feeding roller 16 is provided at a substantially intermediate position between the claw members 15a and 15b.
The paper feed roller 16 is in contact with the leading end of the uppermost recording paper 9 of the recording paper 9 pushed upward by the bottom plate 8. The paper feed roller 16 is rotated clockwise in FIG. 2 by a drive motor (not shown) to separate the recording paper 9 on the bottom plate 8 together with the claw members 15a and 15b one by one from the recording paper 9 on the uppermost stage. Send out.

The bottom surface 7a of the main body case 7 of the paper feed cassette 6
A pair of coil-shaped springs (elastic members) 17 is disposed on the distal end side of the bottom plate 8.
Abuts on the bottom plate 8 when descends due to its own weight,
The lowering speed of the bottom plate 8 is suppressed, and collision between the bottom plate 8 and the bottom surface 7a of the main body case 7 is prevented. That is, the paper cassette 6
Is pulled out of the copying apparatus 1, the driving pin 12 is released from the connection with the connecting portion 14, the ascending lever 10 can freely rotate, and the bottom plate 8 has its own weight as shown by an arrow in FIG. As a result, it pivots (downs) around the hinges 8a and 8b. At this time, the bottom plate 8 is
7, and thereafter, the lowering speed is suppressed by the elasticity of the spring 17, and the lowering is performed smoothly, so that the collision with the bottom surface 7 a is prevented.

Next, the operation of the present embodiment will be described. It is characterized in that an appropriate braking force is applied to the bottom plate 8 descending by its own weight by a spring 17 to reduce an impact sound caused by a collision between the bottom 8 and the bottom surface 7a of the main body case 7.

That is, when the recording paper 9 is set on the bottom plate 8 of the paper feeding cassette 6 and is pushed in the direction indicated by the arrow Fb in FIG. Is connected to the connecting part 14 of the Copier 1
Detects that the paper feed cassette 6 is attached,
3 is driven to rotate, and the drive pin 12 connected to the connection portion 14 of the lifting motor 13 is driven to rotate.

When the drive pin 12 is rotated, the drive shaft 11 rotates, and the lift lever 10 fixed to the drive shaft 11 rotates clockwise in FIG. A lifting lever 10 disposed below pushes the bottom plate 8 upward. When the bottom plate 8 is pushed up, the hinge portion 8a,
The recording paper 9 on the bottom plate 8 is pushed upward by the upward rotation of the bottom plate 8, and both ends of the recording paper 9 are clawed. Member 15
a, 15b, and feed rollers 16
Abuts. When the recording paper 9 abuts the paper feed roller at a predetermined pressure, the copying apparatus 1 stops driving the ascent motor 13.

When the paper feed roller 16 is rotated in this state, the recording paper 9 on the bottom plate 8 is moved to the paper feed roller 16 and the claw member 15.
According to a and 15b, the recording paper 9 at the uppermost stage is separated and sent out one by one.

The paper feed cassette 6 is pulled out of the copying apparatus 1 when the recording paper 9 is replenished or the like.
When pulled out in the direction indicated by a, the connection between the connecting portion 14 of the lifting motor 13 and the drive pin 12 is released. Connecting part 1
When the connection between the drive pin 4 and the drive pin 12 is released, the lift lever 10 is fixed to the drive shaft 11 to which the drive pin 12 is fixed, so that it can rotate freely and is urged upward by the lift lever 10. The bottom plate 8, which has been lifted, loses the urging force (lifting force) of the lifting lever 10 and its own weight causes the bottom plate 8 shown in FIG.
As shown by the middle arrow, rotation starts downward.

The bottom plate 8 that has started descending attempts to collide with the bottom surface 7a of the main body case 7, but a pair of springs 17 is fixed to the tip of the bottom surface 7a.
Abuts on the spring 17 and its descending speed is suppressed. Therefore, the bottom plate 8 descending by its own weight is provided with an appropriate braking force by the spring 8 having an inexpensive and simple configuration, so that the impact sound caused by the collision between the bottom plate 8 and the bottom surface 7a of the main body case 7 is appropriately and inexpensively. Can be reduced.

In the above embodiment, the coil-shaped spring 17 is used as the elastic member. However, the elastic member is not limited to the coil-shaped spring 17 and a braking force suitable for lowering the bottom plate 8 is used. May be anything as long as it gives, for example, for example,
It may be a rubber material or the like having a predetermined elasticity.

FIG. 4 is a diagram showing a second embodiment of the paper feed cassette of the present invention. In this embodiment, the lowering speed of the bottom plate is suppressed by a friction member.

This embodiment is applied to the same copying apparatus and paper feed cassette as those in the first embodiment. In the description of the present embodiment, the first embodiment is different from the first embodiment. The same components are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 4 is a perspective view of a main part of a paper feed cassette 20 to which a second embodiment of the paper feed cassette of the present invention is applied, and the paper feed cassette 20 has a bottom plate 8 housed in a main body case 7. Have been. The bottom plate 8 is housed in the main body case 7 so as to be rotatable around the hinges 8a, 8b via the hinges 8a, 8b.

Although not shown, an ascending lever 10 is provided between the bottom plate 8 and the bottom surface 7a of the main body case 7, as in the first embodiment. In the same manner as in the first embodiment, it is detachably connected to a connecting portion 14 of a lift motor 13 via a drive shaft 11 and a drive pin 12 (not shown).

The sheet cassette 20 is provided with a pair of claw members 15a and 15b at the upper end on the tip side.
In the copying apparatus 1 in which the paper feed cassette 20 is mounted, a paper feed roller 16 that contacts the recording paper 9 in the paper feed cassette 20 is provided.

The paper feed cassette 20 is provided on the inner surface at the distal end of the side walls 7 b and 7 c of the main body case 7.
The flocking pads (friction members) 21a and 21b are fixed over a predetermined width from the upper end portions of the b and 7c to the substantially bottom surface 7a, and the flocking pads 21a and 21b are attached to the bottom plate 8 respectively.
To contact the bottom plate 8 with contact resistance.

Therefore, when the paper feed cassette 20 of the present embodiment is pulled out of the copying apparatus 1 at the time of replenishment of the recording paper 9 or the like, the connection of the ascending motor 13 is performed in the same manner as in the first embodiment. When the connection between the portion 14 and the drive pin 12 is released, the urging force (elevating force) of the elevating lever 10 is lost, and the bottom plate 8 starts rotating (falling) downward by its own weight.

The bottom plate 8 which has started to descend comes into contact with a pair of flocking pads 21a, 21b fixed on both sides 7a, 7b of the main body case 7 at both sides thereof.
Due to the contact resistances a and 21b, the descending speed is suppressed. Accordingly, the bottom plate 8 descending by its own weight is provided with an appropriate braking force by the inexpensive and simple flocking pads 21a and 21b, and the bottom plate 8 and the bottom surface 7 of the main body case 7
The impact noise caused by the collision with a can be reduced appropriately and inexpensively.

In this case, when the flocking direction of the flocking pads 21a and 21b is directed upward, the contact resistance is small when the bottom plate 8 is turned upward by the lifting lever 10, and the contact resistance is low when the bottom plate 8 is lowered. The resistance can be increased, the load on the ascending motor 13 can be reduced, and the bottom plate 8 can be given an appropriate contact resistance to reduce the impact sound caused by the collision between the bottom plate 8 and the bottom surface 7a of the main body case 7. , Can be reduced at low cost.

In the above embodiment, the flocked pads 21a and 21b are used as the friction members. However, the friction members are not limited to the flocked pads 21a and 21b. Give resistance,
Any member may be used as long as the lowering speed of the bottom plate 8 can be appropriately suppressed.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

For example, in each of the above-described embodiments, the case where the present invention is applied to the paper feed cassettes 6 and 20 of the copying apparatus 1 has been described. However, the present invention is not limited to this, and may be, for example, a printer or a facsimile machine.

[0049]

According to the sheet cassette of the present invention, the bottom plate is lowered by its own weight in the main body case, between the bottom surface of the main case and the bottom surface of the bottom plate. Since a predetermined elastic member that suppresses the lowering speed of the bottom plate by acting on the bottom plate is provided, an appropriate braking force can be applied to the lowering of the bottom plate by its own weight by a simple and small-sized mechanism. It is possible to appropriately and inexpensively reduce the impact noise caused by the impact with the bottom surface of the case.

According to the paper feed cassette of the second aspect of the present invention, since the spring is used as the elastic member,
With a smaller and simpler mechanism, it is possible to apply an appropriate braking force to the lowering of the bottom plate due to its own weight, and it is possible to more appropriately and inexpensively reduce the impact noise caused by the impact between the bottom plate and the bottom of the main body case. Can be reduced.

According to the third aspect of the invention, the bottom plate acts on the side surface of the bottom plate between the side surface of the bottom case and the side surface of the bottom case of the paper supply cassette in which the bottom plate descends by its own weight in the main body case. Since a predetermined friction member that suppresses the lowering speed of the bottom plate is provided, an appropriate braking force can be applied to the lowering of the bottom plate by its own weight by a simple and small mechanism, and the bottom plate and the bottom surface of the main body case are provided. Thus, the impact sound caused by the impact can be appropriately and inexpensively reduced.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a copying apparatus to which a sheet cassette to which a sheet cassette according to a first embodiment of the present invention is applied is mounted.

FIG. 2 is a side sectional view of a main part of the paper feed cassette of FIG.

FIG. 3 is a perspective view of a main part of the sheet cassette of FIG. 1;

FIG. 4 is a perspective view of a main part of a paper feed cassette to which a second embodiment of the paper feed cassette of the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier 6 Paper feed cassette 7 Main body case 7a Bottom surface 7b, 7c Side wall 8 Bottom plate 8a, 8b Hinge part 9 Recording paper 10 Lifting lever 11 Drive shaft 12 Drive pin 13 Lifting motor 14 Connection part 15a, 15b Claw member 16 Feeding roller 17 Spring 20 Paper cassette 21a, 21b Flocked pad

Claims (3)

[Claims] 1. A bottom plate on which a plurality of sheets are placed rises in a main body case by a lifting force applied from a predetermined lifting mechanism, and the paper sheet placed on the bottom plate by a paper feed roller. Are separated and conveyed one by one, and when the lifting force of the bottom plate by the lifting mechanism is released, the bottom plate descends by its own weight in the main body case. Between the bottom plate and the bottom plate,
A sheet feeding cassette, wherein a predetermined elastic member which acts on a bottom surface side of the bottom plate to suppress a lowering speed of the bottom plate is provided. 2. The sheet feeding cassette according to claim 1, wherein said elastic member is a spring. 3. A bottom plate on which a plurality of sheets are placed rises in the main body case by a lifting force applied from a predetermined lifting mechanism, and the sheet placed on the bottom plate by a paper feed roller. Are separated and conveyed one by one, and when the lifting force of the bottom plate by the lifting mechanism is released, the bottom plate is a paper feed cassette that descends by its own weight in the main body case. Between the side of the bottom plate,
A paper cassette, wherein a predetermined friction member acting on a side surface of the bottom plate to suppress a lowering speed of the bottom plate is provided.