JP4123710B2 - Paper feeder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technology of a paper feeding device that feeds paper to a recording portion thereof in an image reading device such as a copy / facsimile copying machine, and more particularly, to a flapper attached to a multi-manual feed portion so as to be vertically rotatable. The present invention relates to a lifting mechanism.
[0002]
[Prior art]
In an image reading apparatus such as a copy / facsimile copier, usually, a plurality of stages of paper feed cassettes are provided in the lower part thereof, and sheets of different sizes are set in the respective paper feed cassettes. In addition to the paper feed cassette, a multi manual feed section is provided on one side of the apparatus, and a paper of a desired size can be inserted into the multi manual feed section. The sheet is fed from the recording section to the recording section.
A flapper for loading paper is pivotally supported in the multi-manual feed section, and a pickup roller is disposed above the flapper. Further, a biasing means such as a spring is interposed between the flapper and the bottom surface of the paper feed cassette, whereby the flapper is biased upward so that the paper placed on the flapper hits the pickup roller. It is supposed to touch.
The pickup roller and the separation pad constitute a paper separation mechanism.
[0003]
Thus, when a plurality of sheets are fed to the recording unit at a time, the sheets set on the flapper are separated one by one by the pickup roller and the separation pad and fed to the recording unit. It was.
In the case of using the separation pad method as described above, if the flapper is kept pressed down, it is easy to set the recording paper, and the pickup roller is rotated in order to automatically push down the flapper. A cam is attached to the fulcrum shaft, and the surface of the cam that rotates eccentrically and has the maximum distance from the pivot fulcrum shaft is brought into contact with the flapper and pushed downward.
[0004]
Conventionally, a flapper made of sheet metal has been configured such that its side surface is bent and bent into an “L” shape, and the cam is in contact with the horizontal plane. Alternatively, a stand is protruded on the side surface of the flapper, a roller is pivotally supported by the stand, and the cam is in contact with the roller.
In this way, the surface having the maximum distance from the rotation fulcrum shaft of the cam rotates to the lowest position in the rotation locus, and the surface comes into contact with the horizontal surface or the roller where the flapper is bent. It was pushed down to a predetermined position against the push-up force due to the like.
[0005]
[Problems to be solved by the invention]
However, if the cam contact portion of the flapper is formed by bending the side surface of the flapper, the processing is simple and certainly advantageous in terms of cost, but dust or the like accumulates on the horizontal surface where the flapper is bent. In addition, the frictional resistance between the horizontal surface and the cam increases, and the slidability of the cam decreases. As a result, when the pickup roller is rotated, for example, when the paper is fed, the cam feels to be lightly caught on the horizontal surface, and a large rotational torque is required for the rotational axis of the pickup roller. When the rotational torque transmitted to is insufficient, the motor causes a step-out phenomenon, and each roller stops.
[0006]
Therefore, as in the latter case of the prior art, a structure is provided in which a roller is provided on the side surface of the flapper and a cam is brought into contact with the roller. In this case, dust or the like is not easily accumulated by the rotation of the roller. However, attaching the roller leads to an increase in cost, and it takes time to assemble the roller, resulting in a new problem.
[0007]
In the present invention, in view of the problems of the above two prior arts, a flapper in a sheet feeding device has a structure in which dust and the like are hardly collected at the cam contact portion in the flapper while suppressing the cost increase of the device as much as possible. It is an object to improve the lifting mechanism.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the present invention uses the following means.
That is, as described in claim 1, a flapper for placing a plurality of sheets;
A pick-up roller that sequentially feeds the sheets stacked on the flapper from the uppermost sheet;
Biasing means for biasing the flapper upward;
A cam attached to the rotation shaft of the pickup roller, a rotation locking plate provided so as to rotate integrally with the outer surface of the cam, and a claw portion provided at one place on the outer periphery, and a cylindrical shape protruding from the flapper A cam mechanism that separates and contacts the flapper and the pickup roller,
A locking plate that has a claw portion that engages and disengages with the claw portion of the rotary locking plate at the front end, and is sucked and released by the solenoid;
Comprising
In the cam mechanism, when the solenoid is energized, the locking plate is lowered, the claw portion of the locking plate is engaged with the claw portion of the rotation locking plate, and the distance from the rotation shaft The surface of the cam where the maximum value comes into contact with the shaft .
[0009]
Further, as described in claim 2, a manual feed door that can be opened and closed is provided on the front surface of the apparatus,
The solenoid is energized by opening the manual feed door .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment according to the present invention will be described with reference to a copy / facsimile multifunction peripheral.
1 is a perspective view of a copier / facsimile multifunction peripheral, FIG. 2 is a perspective view of a flapper 11, FIG. 3 is a side sectional view of a multi-manual feeder 1 showing a lowered state of the flapper 11, and FIG. FIG. 5 is a side view showing a state in which the cam 14 is locked.
[0011]
In the following description, the front / rear and left / right directions of each structure will be described with the direction indicated by the arrow in FIG. 1 (the handle side of the paper feed trays 4T and 4B in the case of a copy / facsimile multifunction peripheral) as the front. Further, the front, rear, left, and right directions in other drawings are also the same as those in FIG.
[0012]
As shown in FIG. 1, the copy / facsimile multifunction peripheral is configured by arranging a reading unit 3 above a recording unit 2.
The reading unit 3 is used as a flatbed type scanner that scans a reading device provided in the reading table 6 and reads a stationary document or the like, and also fixes the position of the reading device so that the document is pressed against the document. 7 is configured to be used as a sheet feed type scanner that performs reading while feeding to an automatic document feeder (ADF) 8 attached to one end of the document feeder 7.
[0013]
Below the recording unit 2, paper feed cassettes 4T and 4B are arranged in two upper and lower stages (or a plurality of stages). In the paper feed cassettes 4T and 4B, papers having different paper sizes are accumulated and stored, and the paper is fed out from either one of the paper feed cassettes 4T and 4B and fed to the recording unit 2, After recording on the sheet, the recorded sheet is discharged to the discharge tray 5 and accumulated.
[0014]
In addition to the paper feed cassettes 4T and 4B, a manual feed door 10 is provided on the front surface of the apparatus. The manual feed door 10 is opened and a sheet of a desired size is inserted into the multi manual feed section 1 therein. It is possible to feed the paper from the multi-manual feed unit 1 to the recording unit 2 as well.
[0015]
Next, the multi manual feed section 1 will be described.
As shown in FIGS. 1 to 4, the manual feed door 10 provided on the front surface of the apparatus is configured to be openable and closable, and the upper surface of the manual feed door 10 is used as a tray as a sheet mounting table when the manual feed door 10 is opened. You can also.
A multi manual feed section 1 is provided in a space from the opening of the manual feed door 10 to the back side thereof, and the multi manual feed section 1 is provided with a paper feed mechanism shown below.
[0016]
A flapper 11 on which paper is placed is disposed on the back side of the multi-manual feed unit 1, and pin portions 11a and 11a protruding on both side surfaces thereof are pivotally supported on the apparatus main body side so as to be vertically rotatable. It is configured. A rear end side of the flapper 11 is biased upward by a biasing means such as a spring 12, and a pickup roller 13 is disposed at an upper position on the rear end side of the flapper 11. The rear end center and the pickup roller 13 are in contact with each other.
[0017]
The pickup roller 13 is a roller for feeding the paper placed on the flapper 11, and its rotation fulcrum shaft 13 a is horizontally mounted in a space formed from the opening of the manual feed door 10 toward the back side. It is pivotally supported. A gear, a clutch (not shown) and the like are provided around one end of the rotation fulcrum shaft 13a, and in addition, a fan-like cam 14 is provided.
[0018]
Here, the cam 14 is fixedly attached to the rotation fulcrum shaft 13a, and, as shown in FIGS. 2 and 5, the outer surface of the cam 14 has a claw portion at one place on the outer periphery thereof. A “6” -shaped rotation locking board 16 provided with 16 a is provided in a side view, and is configured to rotate integrally with the cam 14.
Reference numeral 17 denotes a locking plate that is sucked and released by a solenoid 18, and a claw portion 17 a that engages with and disengages from the claw portion 16 a of the rotary locking plate 16 is formed at the front end portion thereof.
[0019]
As shown in FIGS. 2 and 3, a shaft 15 is protruded from the rear side surface of the flapper 11 at a position facing the cam 14 in the vertical direction, and the outer peripheral surface 15a of the shaft 15 and the cam 14 are rotated. The surface (outer peripheral surface) is configured to abut.
[0020]
The shaft 15 is integrally attached to or formed on the flapper 11 so as to improve the strength surface, and further, the outer peripheral surface 15a of the shaft 15 is surface-treated so as to reduce the friction coefficient, or a cylindrical shape. The outer surface 15a of the shaft 15 may be formed into a curved surface, for example, to make the contact with the cam 14 smooth and reduce the sliding resistance.
[0021]
The cam 14 has a region having a relatively long distance from the rotation fulcrum shaft 13a and a short region. As a result, the cam 14 rotates eccentrically. When the surface 14a having the maximum distance is at the lowermost position in the rotation trajectory, the surface 14a abuts against the shaft 15 of the flapper 11, so that the flapper 11 has a predetermined position against the pushing force of the spring 12. Pushed down.
[0022]
However, in this state, the flapper 11 tries to rise by the restoring force of the spring 12, the cam 14 is pushed obliquely upward, and the surface 14a of the cam 14 naturally escapes from the flapper 11, as shown in FIG. The cam 14 is rotated halfway to return the flapper 11 to the raised state.
[0023]
Therefore, as shown in FIG. 5, the solenoid 18 is energized, the locking plate 17 is lowered, the claw portion 17a is engaged with the claw portion 16a of the rotary locking plate 16, and the cam 14 runs around. Accordingly, the flapper 11 is stably held at a predetermined pressing position, and the sheets stacked on the upper surface thereof are kept in a non-contact state with respect to the pickup roller 13.
[0024]
For example, if the circuit is assembled so that the solenoid 18 is energized when the manual door 10 is opened, and the flapper 11 is kept pressed down, a sheet of paper can be fed to the multi manual feed section 1. Easy to set and workability is improved.
[0025]
In the present invention, since the passive body of the cam 14 is constituted by the shaft 15 as described above, dust or the like hardly accumulates on the surface of the shaft 15, so that the contact between the shaft 15 and the cam 14 is also smooth. Thus, maintainability is improved.
Further, the shaft 15 can be easily attached to the flapper 11 and can improve the assemblability. Further, the shaft 15 can be configured at a lower cost than the case where a roller is used for the contact portion with the cam 14, and the cost can be reduced. Can be achieved.
[0026]
【The invention's effect】
The present invention is configured as described above in the sheet feeding device, and thus has the following effects.
That is, as in claim 1, a flapper for placing a plurality of sheets, a pickup roller for feeding the sheets stacked on the flapper in order from the uppermost sheet, and an urging force for upwardly pushing the flapper Biasing means, a cam attached to the rotation shaft of the pickup roller, a rotation locking plate provided with a claw portion at one outer periphery provided to rotate integrally on the outer side surface of the cam, and a protrusion on the flapper A cylindrical shaft, a cam mechanism that separates and contacts the flapper and the pickup roller, and a claw portion that engages and disengages the claw portion of the rotary locking plate at the front end, and a solenoid A locking plate that is sucked and released by suction, and the cam mechanism is lowered when the solenoid is energized, and the claw portion of the locking plate is rotated and locked. Engage with the claws of the board As well as the by the plane of the cam the distance from the rotation axis becomes maximum is brought into contact with the shaft, to prevent Nigemawari cam, flapper stably held at a predetermined depressed position, on its upper surface The stacked paper can be kept in a non-contact state with respect to the pickup roller.
In addition, dust or the like hardly accumulates on the surface of the shaft that is the passive body of the cam , and maintenance can be improved.
Furthermore, compared to the case where a roller is used for the abutting portion with the cam, it can be configured at a lower cost, the cost can be reduced, troubles such as breakage are less likely to occur, and the shaft is easily attached to the flapper. Therefore, the assembling property can be improved.
[0027]
According to another aspect of the present invention, a manual feed door that can be opened and closed is provided on the front side of the apparatus , and the solenoid is energized by opening the manual feed door so that the flapper is kept pressed down. Therefore, it is easy to set paper and workability is improved.
[Brief description of the drawings]
FIG. 1 is a perspective view of a copy / facsimile multifunction peripheral.
FIG. 2 is a perspective view of a flapper 11;
FIG. 3 is a side sectional view of the multi-manual feed portion 1 showing a lowered state of the flapper 11;
FIG. 4 is a side cross-sectional view of the multi-manual feed portion 1 showing a raised state of the flapper 11;
FIG. 5 is a side view showing a locked state of the cam 14;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Paper feeder 10T Paper cassette 10B Paper cassette 11 Flapper 13 Pickup roller 13a Rotation fulcrum shaft 14 Cam 14a Surface 15 Shaft 15a Outer peripheral surface

Claims (2)

A flapper for placing a plurality of sheets;
A pick-up roller that sequentially feeds the sheets stacked on the flapper from the uppermost sheet;
Biasing means for biasing the flapper upward;
A cam attached to the rotation shaft of the pickup roller, a rotation locking plate provided so as to rotate integrally with the outer surface of the cam, and a claw portion provided at one place on the outer periphery, and a cylindrical shape protruding from the flapper A cam mechanism that separates and contacts the flapper and the pickup roller,
A locking plate that has a claw portion that engages and disengages with the claw portion of the rotary locking plate at the front end, and is sucked and released by a solenoid;
Comprising
In the cam mechanism, when the solenoid is energized, the locking plate is lowered, the claw portion of the locking plate is engaged with the claw portion of the rotation locking plate, and the distance from the rotation shaft The surface of the cam where the maximum is in contact with the shaft,
A paper feeder characterized by that. A manual feed door that can be opened and closed is provided on the front of the device.
The solenoid is energized by opening the manual feed door.
The paper feeding device according to claim 1.

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