JPH045476Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> This invention relates to a paper feeding device for feeding paper from a paper cassette or the like to a processing device such as a copying machine.

<Summary of the invention> The paper feeding device of this invention attempts to simplify the device by returning the half-moon paper feeding roller to its home position by following the movement of the paper as it is pulled forward. It is something.

<Prior art and its disadvantages> In paper feeding devices such as copying machines and laser printers, paper stacked in a cassette or the like is fed by feeding the sheets one by one from the front of the upper end by rotating a paper feeding roller. ing. There are two types of paper feeding rollers: one with a normal circular cross section and one with a partially cut-out half-moon shape. Half-moon paper feed rollers having a half-moon cross-sectional shape are widely used because they are advantageous in terms of ease of attaching and removing cassettes, stabilization of paper feeding, and cost. However, when using a half-moon paper feeding roller, it is necessary to control the roller so that it returns to the home position where the notch is directly below every time one sheet of paper is fed.
For this reason, conventionally, the drive from the drive device was transmitted to the half-moon paper feed roller via a spring clutch, and the sleeve of this spring clutch was locked with a latch by the operation of a solenoid, resulting in a complicated structure. Furthermore, adjustment during assembly of the transmission mechanism was troublesome.

The structure and operation of a conventional paper feeding device will be described below with reference to FIGS. 6 to 10. A drive from a drive device (not shown) is transmitted to a drive input boss 1 as shown in FIG. 6, and is transmitted to a half-moon paper feed roller 3 via a spring clutch 2. The half-moon paper feed roller 3 is fixed to a rotating shaft 4. A clutch boss 5 of the spring clutch 2 is fitted onto this rotating shaft 4 and fixed with a screw 6. The clutch spring 7 is a torsion coil spring, and one end thereof is fixed to the clutch boss 5. The clutch sleeve 8 is fitted so as to cover the outer periphery of the clutch spring 7, and fixes the other end of the clutch spring 7. The drive input side boss 1 is connected to the rotation shaft 4
It is fitted between the boss part and the clutch spring 7.
It is inserted into the inner diameter of the other end. When the clutch spring 7 stops, the clutch sleeve 8 stops and the clutch boss 5
is wound in such a direction that it loosens when rotated in the direction of rotation of the half-moon paper feed roller 3. clutch sleeve 8
is provided with a protruding sleeve stopper 9 near one end of the outer periphery, and a flange 1 on the other end.
0, and sleeve external teeth 11 are formed inside a canopy formed at the outer peripheral end of this collar portion 10.
This flange portion 10 is provided with a portion that is not formed from the position where the sleeve stopper 9 of the clutch sleeve 8 is formed to the rear side in the rotational direction. One end of the latch 12 is locked to the sleeve stopper 9 of the clutch sleeve 8. The latch 12 is an actuating portion of a locking mechanism of the clutch sleeve 8, which is supported so as to be swingable about its center and whose other end is connected to the actuator of the solenoid 13. This latch 12 is connected to the solenoid 13.
When in the OFF state, one end is pulled by the spring 14 and is engaged with the sleeve stopper 8 of the clutch sleeve 8. Also, solenoid 13 is ON
Then, the other end of the latch 12 is pulled by the actuator, and the one end is released from the sleeve stopper 9 and is also engaged with the external sleeve teeth 11 of the flange 10.

In this conventional paper feeding device configured as described above, in a paper feeding standby state, as shown in FIGS. 7A and 7B, one end of the latch 12 is connected to the clutch sleeve 8.
The spring clutch 2 is engaged with the sleeve stopper 9, and the clutch spring 7 is loosened to cut off power transmission to the spring clutch 2. At this time, the half-moon paper feeding roller 3 has its cutout portion facing substantially downward and away from the upper end of the paper 16 loaded in the cassette 15. When the paper feeding operation starts, the solenoid 13 is energized for 0.1 seconds,
As one end of the latch 12 is lifted, the sleeve stopper 9 is released and the clutch sleeve 8 is released.
becomes free. Then, the clutch spring 7 closes and tightens the boss portion of the drive input side boss 1, and the driving force from the drive input side boss 1 is transmitted to the rotating shaft 4 via the clutch spring 7 and the clutch boss 5, as shown in FIG. As shown in A and B, the half-moon paper feed roller 3 starts rotating. Note that some parts of the flange 10 of the clutch sleeve 8 are not formed, so when the latch 12 is once released from the sleeve stopper 9, the latch 12 is removed from the flange 10.
The sleeve external teeth 11 are not locked. One of the top sheets of paper 16 is fed out by three rotations of the half-moon paper feed roller, and its tip reaches the paper stop roller 1.
7, 17, the solenoid 13 is energized and one end of the latch 12 is engaged with the sleeve external teeth 11, as shown in FIGS.
is stopped, the transmission of the spring clutch 2 is cut off, and the rotation of the half-moon paper feed roller 3 is stopped. In this state, the timing with the photoreceptor drum 18 is measured and the paper stop rollers 17, 17 start rotating and begin to feed the paper 16. As shown in FIGS. 10A and 10B, the solenoid 13 The power supply is cut off to release the latch 12 from the sleeve external teeth 11. Then, the spring clutch 2 is connected, and the half-moon paper feed roller 3 starts rotating again, and the latch 12
The sleeve stops when one end thereof locks the sleeve stopper 9 and returns to the state shown in FIGS. 7A and 7B.

In this manner, the conventional paper feeding device is configured such that the half-moon paper feeding roller 3 returns to the home position each time it feeds one sheet of paper 16. However, in such a configuration, the flange 1 of the clutch sleeve 8
0, the structure becomes complicated, and the clutch boss 5 is set so that the half-moon paper feed roller 3 is in its home position at the position where the latch 12 locks the sleeve stopper 9. When fixing to the rotating shaft 4 with the screws 6, the position must be adjusted, making the assembly work cumbersome.
Furthermore, the energization to the solenoid 13 is also 0.1 at first.
Since it is necessary to conduct electricity for two different periods, once for a second and then from when the leading edge of the paper 16 reaches the paper stop rollers 17 until the paper stop roller 17 starts rotating,
The control mechanism becomes complicated. For this reason, the conventional paper feeding device has the disadvantage that the structure is complicated and assembly work is troublesome.

<Purpose of the invention> This invention was created in view of the above circumstances, and it transmits the drive from the drive device to the half-moon paper feed roller via a spring clutch and one clutch, and also uses a locking function to transmit the drive from the drive device to the semicircular paper feed roller. It is an object of the present invention to provide a paper feeding device which has a simple structure and does not require assembly and adjustment by making it possible to stop a clutch sleeve at an appropriate position.

<Structure and Effects of the Invention> The paper feeding device of this invention is a paper feeding device that feeds stacked sheets one by one from the front of the upper end to the conveyance roller of a processing device by rotation of a half-moon feeding roller. The drive from the drive device is transmitted to the half-moon paper feed roller through a spring clutch that transmits rotation when the clutch sleeve rotates, and a one-way clutch that transmits rotation only in the drive direction. The clutch sleeve is characterized by being provided with a locking mechanism that releases the stopped state of the clutch sleeve only until the leading end reaches the conveying roller.

When the paper feeder of this invention is constructed as described above, the clutch sleeve is released from its stop at the start of paper feeding, and the spring clutch transmits the rotation of the drive device to the semicircular paper feed roller. This causes the half-moon paper feed roller to rotate, and paper begins to be fed. When the leading edge of the fed paper reaches the conveyance roller of the processing device, which is a standby position for timing adjustment, the clutch sleeve is stopped again by the locking mechanism.
The spring clutch no longer transmits rotation, and the paper stops with its leading edge in contact with the conveyance roller. This half-moon paper feed roller is in contact with the paper, and one side of the half-moon paper feed roller is resting on the clutch and is free to rotate in the paper feeding direction. Therefore,
When the paper moves in the paper feeding direction due to the rotation of the conveyance roller, the half-moon paper feeding roller rotates following the paper and stops at a home position where it no longer makes contact with the paper.

In this way, it is only necessary to release the stop of the clutch sleeve at the start of paper feeding and stop it again when the leading edge of the paper reaches the conveyance roller, so the mechanism of the clutch sleeve is extremely simple and the operation of the solenoid etc. can be controlled. The mechanism can also be simplified. Furthermore, the half-moon paper feed roller rotates following the paper and automatically returns to its home position.
Eliminates the need for position adjustment during assembly work.

<Embodiment> FIG. 1 is a schematic perspective view for explaining the structure of a paper feeding device which is an embodiment of this invention.

The paper feeding device of this embodiment includes a drive input side boss 1, a spring clutch 2, a one-side clutch 19, and a solenoid 1, which transmit the drive from a drive device (not shown).
3 and a latch 12, and a half-moon paper feed roller 3. The half-moon paper feeding roller 3 is attached to the rotating shaft 4 via a one-way clutch 19 fitted into the inner diameter portion. This one-way clutch 19 transmits only the rotation of the rotary shaft 4 in the driving direction to the half-moon paper feed roller 3. The drive input side boss 1 and the spring clutch 2 are attached to the rotating shaft 4 in the same manner as in the prior art. The clutch sleeve 8 of this spring clutch 2 has saw teeth 20 formed all over its outer circumference. The latch 12 is supported with its central portion as a fulcrum, has a claw portion 21 at one end, and is connected to the actuator of the solenoid 13 at the other end. This latch 12 is connected to the solenoid 1
3 is energized and the actuator operates, the claw portion 21
is caught in the saw teeth 22 of the clutch sleeve 8, stopping the rotation of the clutch sleeve 8, and the solenoid 1
When the saw blade 3 is not energized, the claw portion 21 is separated from the saw tooth 20 by a spring 14.

The operation of the paper feeding device of this embodiment configured as described above will be explained based on FIGS. 2 to 5. In the paper feeding standby state, as shown in FIGS. 2A and 2B, the claw portion 21 of the latch 12 engages the saw teeth 20 to stop the clutch sleeve 8 and cut off the transmission of the spring clutch 2, and the half-moon paper feeding roller 3 is stopped at home position. When paper feeding is started, the solenoid 13 is energized, the actuator is operated, the pawl 21 of the latch 12 is disengaged from the sawtooth 20, and the clutch sleeve 8 becomes free. Then, as shown in FIGS. 3A and 3B, the clutch spring 7 is tightened and tightens the boss portion of the drive input side boss 1, so that the transmission of the spring clutch 2 is connected and the half-moon paper feed roller 3 starts rotating. When the leading edge of the paper 16 reaches the paper stop rollers 17, 17 as shown in FIGS.
is caught in the saw teeth 20 and stops the clutch sleeve 8. Therefore, as shown in FIGS. 4A and 4B, the half-moon paper feed roller 3 also stops mid-rotation and waits for the paper stop rollers 17, 17 to start rotating. When the paper stop rollers 17, 17 start rotating in synchronization with the photosensitive drum 18, the paper 16 is drawn from the cassette 15 into the transfer section of the photosensitive drum 18. Then, as shown in FIGS. 5A and 5B, the half-moon paper feed roller 3 idles on one clutch 19 as the paper 16 is fed, and stops near the home position. , return to state B.

As explained above, in the paper feeding device of this embodiment, the half-moon paper feeding roller 3 returns to the home position due to the following action when the paper stop rollers 17, 17 pull in the paper 16. 2 position adjustment is completely unnecessary. When the half-moon paper feed roller 3 rotates to a position where the notch is downward, it no longer comes into contact with the paper 16, so it automatically stops at the home position. Furthermore, since the clutch sleeve 8 of the spring clutch 2 only needs to be provided with saw teeth 20 on its outer periphery, the structure is simple and can be manufactured at low cost. Additionally, the solenoid that activates the latch 12 is
One sheet feeding operation is completed by simply turning ON and turning OFF when the leading edge of the paper 16 reaches the paper stop roller 17, making the control mechanism extremely simple. Therefore, the paper feeding device of this embodiment has a simple structure and eliminates the need for troublesome assembly and adjustment, which can contribute to reducing the cost of the product.

[Brief explanation of drawings]

Fig. 1 is a schematic perspective view for explaining the structure of a paper feeding device which is an embodiment of this invention, Fig. 2A,
B to 5A and 5B are side views for explaining the operation of the paper feeder, FIG. 6 is a schematic perspective view for explaining the structure of the conventional paper feeder, and FIGS. 7A,
B to FIG. 10A and B are side views for explaining the operation of a conventional paper feeding device. 2...Spring clutch, 3...Half-moon paper feed roller, 8...Clutch sleeve, 12...Latch, 13...Solenoid, 16...Paper, 19...
...On the other hand, Kuratsuchi.

Claims (1)

[Scope of Claim for Utility Model Registration] In a paper feed device that feeds sheets one by one from the front of the upper end of a stack of sheets to a conveyance roller of a processing device by rotation of a half-moon feed roller, the drive from the drive device When the clutch sleeve rotates, the rotation is transmitted to the half-moon paper feed roller via a spring clutch that transmits rotation, and a one-way clutch that transmits rotation only in the driving direction. A paper feeding device characterized in that a locking mechanism is provided for releasing the stopped state of the clutch sleeve only between the clutch sleeves.