JPH10120197A - Paper feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify structure and to improve workability of change of recording paper by furnishing a paper feeding roller provided on the side of a device main body and to feed the recording paper placed on a paper feeding main body and a pressurizing plate to push up the placed recording paper from below by providing a proper interval with the paper feeding roller on the side of the device main body. SOLUTION: A pressurizing plate 1 and a bottom part 9 of a device main body are engaged with each other at one point of an engagement part 10, and left and right arms of the pressurizing plate 1 are respectively made free to move vertically independently with the engagement part 10 as a fulcrum and made to constantly and uniformly make contact with recording paper. A spring 12 pushes up the pressurizing plate 1 by elastic force and press fits the recording paper on a paper feeding roller 6. A cover of a paper feeding cassette is opened, an end guide 16 is drawn out to the front, the recording paper is placed on a paper feeding cassette main body 8, the end guide 16 is pushed in, and a rear end of the recording paper is regulated. When a device main body is started by operating an operation part, motive power is transmitted to a shaft 4 from a driving source, the shaft 4 starts rotating and the recording paper is carried to a recording part by the paper feeding roller 6 and a conveying roller 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder for supplying recording paper to a recording unit such as a facsimile machine and a copying machine.

[0002]

2. Description of the Related Art Conventionally, a paper feeder used for a facsimile machine, a copying machine, or the like has a rectangular shape having a paper feed cassette main body and two pivot points for pressing the leading end of a recording paper to a paper feed roller. The configuration has a pressing plate and an elevating mechanism of the pressing plate, and a configuration in which a rectangular pressing plate and an elevating mechanism of the pressing plate are accommodated in the sheet cassette main body is adopted.

[0003]

However, as described above,
Integrating the pressing plate and the lifting / lowering mechanism of the pressing plate into the paper cassette main body has the disadvantage that the structure of the paper cassette becomes complicated due to the increase in the number of parts, and the recording and unloading work of the paper cassette is involved. Workability at the time of paper replacement also becomes worse. Furthermore, if the rectangular pressing plate is configured to rotate about two fulcrums, the pressing plate may not move up and down in a parallel left and right state due to manufacturing errors of components, aging, etc. As a result of the plate colliding against the recording paper, there is a disadvantage that the recording paper is fed obliquely. In addition, since an elastic body such as a spring provided on the back side of the pressing plate jumps up the pressing plate, the amount of recording paper placed on the pressing plate is small, and the distance between the pressing plate and the recording paper pressing claw is small. When is opened, an unpleasant impact sound and a contact noise are generated around the sheet feeding roller, and the accumulation of the impact may adversely affect the electronic components. The present invention has been made in view of such a problem, and an object of the present invention is to provide a sheet feeding device that can simplify the structure of a sheet feeding cassette and improve the workability of exchanging recording sheets. In addition, the recording paper is always properly pressed against the paper feed roller so that the recording paper is smoothly conveyed, and even when the amount of the recording paper is small, the pressing plate does not jump upward and no impact noise is generated. It is an object to provide a paper feeding device.

[0004]

According to one aspect of the present invention, there is provided a paper cassette main body, and a recording paper provided on the apparatus main body and mounted on the paper cassette main body. And a pressing plate provided on the main body of the apparatus at an appropriate distance from the paper feeding roller and configured to press up the loaded recording paper from below.

[0005] With such a configuration, since the pressing plate is not accommodated in the paper feeding cassette, a paper feeding device which can simplify the structure of the paper feeding cassette and improve the workability of exchanging the recording paper can be obtained.

[0006] The invention described in claim 2 is the invention according to claim 1.
In the paper feeder described above, the pressing plate is engaged with the apparatus main body at one point in the center position in the width direction of the recording paper, and is pressed upward by biasing means provided at symmetrical positions on the back surfaces of both ends of the pressing plate. Take the configuration that is energized.

With such a configuration, even when the accumulated error in the manufacturing accuracy of each part is large, both ends of the pressing plate are urged independently in the recording paper direction, and the pressure is evenly applied to the recording paper. Therefore, the recording paper can be properly conveyed, and the contact of the pressing plate with the recording paper, which occurs when the rotation fulcrum of the pressing plate is two points, and the skew of the recording paper that occurs as a result can be avoided. .

[0008] The invention described in claim 3 is the first invention.
Alternatively, in the paper feeding device according to claim 2, a cam interlocked with a paper feed roller, and the pressing plate is provided at both ends of the pressing plate in the width direction of the recording paper in pressure contact with the cam to move the pressing plate up and down by rotation of the cam. A cam receiver for moving the pressing plate, and alternately repeats a sheet feeding state in which the pressing plate is positioned above and a standby state in which the pressing plate is positioned below.

With this configuration, in the paper feeding state, when the paper feed roller conveys the recording paper, the pressing plate is released from the pressure contact by the cam and is provided with an elastic body such as a spring provided on the back side of the pressing plate. As the recording paper is displaced upward by the pressure and pressed against the paper feed roller, the recording paper can be properly conveyed. Further, in a standby state in which the paper is not fed, the cam pushes down the pressing plate and the pressing plate is displaced downward, so that operations such as replenishment and change of recording paper can be easily performed.

[0010] The invention described in claim 4 is the first invention.
4. The sheet feeding apparatus according to claim 3, further comprising a cam and a cam receiver, wherein a buffer portion is formed on an abutting surface thereof to suppress a sudden displacement of the pressing plate from a standby state to a paper feeding state. Take.

With this configuration, the pressing plate can be smoothly rotated upward, so that even if the amount of recording paper placed on the pressing plate is small, the pressing plate is provided on the back side of the pressing plate. It is possible to avoid a situation in which an elastic body such as a spring or the like suddenly displaces the pressing plate upward, and it is possible to prevent the generation of an impact sound between the pressing plate and the peripheral portion of the sheet feeding roller at that time. Adverse effects can also be avoided. The above-mentioned shock-absorbing part may appropriately change the shape of the cam or the cam receiver according to the torque of the motor serving as the driving source or the pressure of the urging means of the pressing plate. One or both may be changed.

The invention described in claim 5 is the first invention.
5. The paper feeding device according to claim 4, wherein a paper feeding roller formed in a sector shape in cross section and a cam are provided coaxially, and a rotation of the cam displaces a pressing plate gradually upward, so that the cam receives the cam receiving member. After the paper is separated from the recording paper, the paper feeding roller contacts the recording paper to feed the paper.

With this configuration, since the cam and the sector-shaped sheet feeding roller are provided coaxially, the two operations of sheet feeding and lifting and lowering of the pressing plate can be performed with a simple structure and with a single driving source. It can be carried out. Also, when the pressing plate comes to an appropriate position for pressing the paper feeding roller and the recording paper by the rotation of the cam, the paper feeding roller comes into contact with the recording paper and starts transporting the recording paper only when the paper is fed. Is always done properly.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below more specifically with reference to the drawings. FIG. 1 is an exploded perspective view of the sheet cassette of the present invention. 1 is a pressing plate having arms on the left and right, and 2 is a pair of cam receivers provided at both ends of the pressing plate 1 in the document width direction. The cam receiver 2 has a buffer 3 on the recording paper advancing direction side.
Are formed to have a smooth L-shaped slope. The cam receiver 2 is configured to contact the pair of cams 5 fixed to the shaft 4 so as to regulate the position of the pressing plate 1 as described later. Further, a paper feed roller 6 for feeding out recording paper is fixed to the shaft 4, and this paper feed roller 6 has a fan-shaped cross section so that one recording paper can be sent out in one rotation. ing.
The cam 5 and the paper feed roller 6 are fixed on the same shaft 4 so as to rotate without changing their positional relationship.
Further, a driving force is intermittently transmitted to the shaft 4 by a clutch (not shown), whereby the sheet feeding device alternately repeats a sheet feeding state and a standby state,
It is configured to convey the recording paper to the recording unit one by one.

The pressing plate 1 has a locking hole 7 and is locked at a single point by a screw 11 to a locking portion 10 provided on the bottom 9 of the apparatus main body in which the paper feed cassette main body 8 is installed.
1 can be turned up and down. Further, since the pressing plate 1 and the apparatus main body bottom portion 9 are engaged at one point of the locking portion 10, the left and right arms of the pressing plate 1 can independently move up and down with the locking portion 10 as a fulcrum. ing. Thus, the recording paper can always be evenly contacted.

Numeral 12 denotes a pair of springs provided for pushing up the pressing plate 1 by its elasticity and for pressing the recording paper against the paper feed roller 6. The upper end is connected to the lower surface of the pressing plate 1, and the lower end is the main body of the apparatus. It couples to a spring receiver 13 provided on the bottom 9. 14 is a conveying roller for conveying the recording paper, 15 is a recording paper pressing claw that regulates the position of the upper end of the recording paper, and 16 is an end guide that regulates the rear end of the recording paper. It is configured to be slidable back and forth so that work such as paper replenishment and replacement can be easily performed.

The operation of the paper feeder configured as described above will be described with reference to the drawings. First, the operator opens the cover of the sheet cassette (not shown), and
To the front. When the recording paper is placed on the paper cassette main body 8 and the end guide 16 is pushed in, the rear end of the recording paper is regulated by this. Next, when an operator operates an operation unit (not shown) to start the apparatus main body, power from a drive source (not shown) is transmitted to the shaft 4, and
The shaft 4 starts rotating, and the recording paper is transported by the paper feed roller 6 and the transport roller 14 to a recording unit (not shown).

A series of these operations will be described in more detail with reference to FIGS. 2 to 9 showing each state of the operations. 2 to 9 are main-portion cross-sectional views showing the operation state of the sheet feeding device of the present invention. FIG. 2 shows the standby state. In this state, the cam 5 comes into contact with the cam receiver 2 near the apex of the cam receiver 2 and presses the pressing plate 1 which is to be rotated upward by the elastic force from the spring 12. When an operator operates an operation unit (not shown) to start the apparatus, a clutch (not shown) is switched, so that the shaft 4
The driving force from the driving source is transmitted to the shaft 4, and the shaft 4 starts rotating.

FIG. 3 shows a state where the shaft 4 is rotated by 20 degrees. In this state, the cam 5 comes into contact with the cam receiver 2 at a position lower than the vertex of the buffer portion 3 of the cam receiver 2,
The pressing plate 1 rotates upward by 5 degrees by the elastic force of the spring 12, and lifts the recording paper.

Further, when the shaft 4 rotates, the state shown in FIG. 4 is obtained. FIG. 4 shows a state where the shaft 4 is rotated 27 degrees. As is apparent from the figure, since the cam 5 is located at the flat portion of the cam receiver 2, the lifting of the pressing plate 1 is temporarily stopped. In this state, the cam 5 abuts on the lowest portion of the buffer portion 3 in the cam receiver 2, so that the pressing plate 1 further rotates upward to lift the recording paper by 7.6 degrees.

By the above-described series of operations, the pressing plate 1 temporarily stops at the flat portion of the cam receiver 2 and then rises to the uppermost portion. Therefore, the pressing plate 1 rises smoothly and does not give an impact to the sheet feeding unit. That is,
The pressing position of the cam 5 and the cam receiver 2 gradually and in two stages in accordance with the rotation of the shaft 4 prevents the pressing plate 1 from being rapidly displaced upward by the elastic force of the spring 13. The pressing plate 1 moves up and down smoothly. Further, since the pressing plate 1 is supported at one point, both ends of the pressing plate 1 in the width direction of the document independently rise following the cam 5, so that the recording paper uniformly hits the paper feed roller 6. Touch

When the shaft 4 further rotates, the state shown in FIG. 5 is obtained. FIG. 5 shows a state where the shaft 4 is rotated by 60 degrees. In this state, the cam 5 comes into contact with the cam receiver 2 at one point, the pressing plate 1 rotates further upward, and the recording paper is lifted by 10 degrees.

Further, when the shaft 4 rotates, the state shown in FIG. 6 is obtained. FIG. 6 shows a state where the shaft 4 is rotated by 80 degrees. In this state, the cam receiver 2 is released from the resistance from the cam 2, the pressing plate 1 is rotated to the uppermost position, and the recording paper 1
Lifted up 1.5 degrees. Also, the paper feed roller 6
Is in the state immediately before trying to contact the recording paper.

Further, when the shaft 4 rotates, the state shown in FIG. 7 is obtained. FIG. 7 shows a state where the shaft 4 is rotated by 100 degrees. Here, the recording paper starts to be conveyed by the paper feed roller 6, but the recording paper is locked by the recording paper pressing claw 15 provided at the end of the apparatus main body bottom 9, and as shown in FIG. Since both ends bend momentarily and return to their original state, paper is always fed one by one.

It should be noted that the cam receiver 2 and the pressing plate 1 released from the resistance from the cam 5 once have a maximum of 11.5 mm as described above.
However, the pressure plate 1 is pressed downward again by the pressure of the paper feed roller 6, and the rotation angle of the pressing plate 1 is reduced from 11.5 degrees to 10 degrees.

Further, when the shaft 4 rotates, the state shown in FIG. 8 is obtained. FIG. 8 shows a state where the shaft 4 is rotated by 200 degrees. In this state, the paper feed roller 6 is located exactly at the midpoint of the distance that the paper feed roller 6 conveys the recording paper, and the pressing plate 1 is further pushed down by the paper feed roller 6,
It is in a state of being turned 9.5 degrees.

Further, when the shaft 4 rotates, the state shown in FIG. 9 is obtained. FIG. 9 shows a state where the shaft 4 is rotated by 230 degrees. In this state, the feeding of the recording paper by the paper feed roller 6 is completed, and the recording paper is transported by the transport roller 14. Further, since the cam 5 starts to apply pressure to the cam receiver 2, the pressing plate 1 starts to descend, and the pressing plate 1 is in a state of being rotated five degrees from a horizontal plane.

Further, when the shaft 4 rotates, it returns to the initial state as shown in FIG. Here, the driving force transmitted to the shaft 4 is stopped being transmitted by disengaging the clutch, and the shaft 4 stops rotating. Thereby, the cam 5
And the paper feed roller 6 stops in the standby state. The recording paper is further transported by a transport roller 14 to a recording unit (not shown), where data recording is performed.

[0029]

As is apparent from the above description, according to the first aspect of the present invention, since the pressing plate is not accommodated in the paper feeding cassette, the structure of the paper feeding cassette is simplified and the recording paper can be replaced. A sheet feeding device capable of improving workability can be obtained.

According to the second aspect of the present invention, even when the accumulated error in the manufacturing accuracy of each component is large, both ends of the pressing plate are urged independently in the direction of the recording paper to perform recording. Since the recording paper can be properly conveyed to apply an equal pressure to the paper, the pressing plate hits against the recording paper when the rotation fulcrum of the pressing plate is two points, and the resulting recording occurs. Paper skew can be avoided.

According to the third aspect of the present invention, in the paper feeding state, when the paper feeding roller conveys the recording paper, the pressing plate is released from the pressure contact by the cam and provided on the back side of the pressing plate. Since the recording paper is displaced upward by the pressure of the elastic body such as the spring and pressed against the paper feed roller, the recording paper can be properly conveyed. Further, in a standby state in which the paper is not fed, the cam pushes down the pressing plate and the pressing plate is displaced downward, so that operations such as replenishment and change of recording paper can be easily performed.

According to the fourth aspect of the present invention, since the pressing plate can be smoothly turned upward, even if the amount of recording paper placed on the pressing plate is small, It is possible to avoid a situation in which an elastic body such as a spring provided on the back side of the pressing plate suddenly displaces the pressing plate upward, thereby preventing the generation of an impulsive sound between the pressing plate and the peripheral portion of the sheet feeding roller. And adverse effects on electronic components can be avoided.

According to the fifth aspect of the present invention, since the cam and the sector-shaped sheet feeding roller are provided coaxially, the two operations of sheet feeding and lifting and lowering of the pressing plate can be performed with a simple structure. Moreover, it can be performed by a single drive source. Also, when the pressing plate comes to an appropriate position for pressing the paper feeding roller and the recording paper by the rotation of the cam, the paper feeding roller comes into contact with the recording paper and starts transporting the recording paper only when the paper is fed. Is always done properly.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of the entire sheet feeding device of the present invention.

FIG. 2 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 3 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 4 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 5 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 6 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 7 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 8 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

FIG. 9 is a sectional view of a main part showing an operation state of the sheet feeding device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressing plate 2 Cam receiver 3 Buffer part 4 Shaft 5 Cam 6 Paper feed roller 7 Lock hole 8 Paper cassette main body 10 Lock part 11 Screw 12 Spring 14 Transport roller 15 Recording paper pressing claw

Claims (5)

[Claims] 1. A paper feed cassette main body, a paper feed roller provided in the apparatus main body for feeding recording paper, and a paper feed roller provided in the apparatus main body at an appropriate distance from the paper feed roller. And a pressing plate for pushing up the recording paper from below. 2. A pressing plate is engaged with the apparatus main body at one central position in the width direction of the recording paper, and is urged upward by urging means provided at symmetrical positions on the back surfaces of both ends of the pressing plate. 2. The sheet feeding device according to claim 1, wherein: 3. A cam interlocking with a paper feed roller, and a cam receiver provided at both ends of the pressing plate in the width direction of the recording paper in pressure contact with the cam, and rotating the cam to move the pressing plate up and down. 3. The sheet feeding device according to claim 1, wherein the sheet feeding device includes a sheet feeding state in which the pressing plate is positioned upward and a standby state in which the pressing plate is positioned downward. 4. A buffer having a cam and a cam receiver, wherein a buffer portion for suppressing a sudden displacement of the pressing plate from a standby state to a paper feeding state is formed on an abutting surface thereof. The sheet feeding device according to claim 1. 5. A feed roller and a cam formed in a fan-shaped cross section are provided coaxially, and the pressing plate is gradually displaced upward by rotation of the cam. 5. The paper feeding device according to claim 1, wherein the paper roller feeds the paper in contact with the recording paper.