JPS6219633Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to an improvement of a paper feeding device for manually feeding sheet paper by an operator in, for example, an electrophotographic apparatus.

[Technical background of the invention]

Electrophotographic equipment is equipped with a paper feeder that allows the operator to manually feed sheets of non-standard size paper in addition to the automatic paper feeder from the paper cassette. However, in such devices, the following has conventionally been used to drive the paper feed roller.
In other words, a main motor that also drives the optical system, developing device, conveyance device, etc. is used as a drive source, and the drive from this main motor is transmitted using a chain and gears, and a coupling device consisting of a spring clutch or an electromagnetic clutch is also used. This is to drive the paper feed roller.

[Problems with background technology]

However, in this device, the drive is carried out via a number of transmission means such as chains and gears, as well as spring clutches or electromagnetic clutches.
There is a possibility that the reliability of the drive will be reduced, and
This has the disadvantage that it generates noise when the chain is driven by the gear, making it noisy when installed and used in an office or the like.

Also, since the paper feed roller always tries to feed the sheet paper at a constant speed after it has pinched the paper,
If the operator pulls on the trailing edge of the sheet during paper feeding, or delays the timing of releasing the sheet, the sheet may be damaged due to the tensile force exerted by the paper feed rollers if the sheet is weak or damaged. It also has the problem of being damaged. Furthermore, when performing a performance test on the paper feeding device during manufacturing, the paper feeding roller cannot be driven unless it is built into the housing and connected to the main motor, making it impossible to test the paper feeding device alone, which can lead to problems with manufacturing. It is also considered impossible to unitize the paper feeding device in order to simplify the process and the interior of the housing, or to improve maintenance.

[Purpose of invention]

This idea was developed based on the above circumstances, and although it has a relatively simple structure, it prevents noise during driving and improves the reliability of the drive. This paper feed system does not waste paper sheets or cause paper jams, improves reliability, and also allows the paper feed device to be integrated into a unit, simplifying the manufacturing process and improving maintenance. The purpose is to provide paper equipment.

[Summary of the idea]

This idea prevents noise by driving the paper feed roller with a pulse motor, and sets the drive torque within the self-starting range of the pulse motor and within the range where the tensile force of the paper feed roller does not damage the sheet paper. This prevents sheet paper from being damaged, improves reliability, and also enables unitization of the device and independent testing during manufacturing.

[Example of idea]

An embodiment of this invention will be described below with reference to FIG. A paper feed unit 10 provided on the side wall of the casing (not shown) can accommodate a lower paper feed cassette 11 and an upper paper feed cassette 12, and a flat manual feed guide plate 13 is attached to the top of the paper feed unit 10. There is. Above each paper feed cassette 11, 12,
A lower paper feed roller 17 and an upper paper feed roller 18 for taking out regular-sized sheets 14 and 15 are provided, and are driven by a first pulse motor 22 via a first transmission device 20 and a second transmission device 21, respectively. It's getting old. That is, the first transmission device 20 includes a gear 123 driven by the motor gear 122a of the first pulse motor 22, and a first one-way clutch 24 that drives the lower paper feed roller shaft 17a.
a gear 226 driven by the gear 123;
The second transmission device 21 includes a motor gear 12
Gear 327 and gear 4 sequentially driven by 2a
28 and a second one-way clutch 30 for driving the upper paper feed roller shaft 18a, and is comprised of a gear 531 driven by the gear 428. On the other hand, in front of the manual feed guide plate 13, a pair of paper feed rollers 33 are provided that pinch and convey various sheets of paper 32 that are manually fed by an operator.
The lower paper feed roller 33a is connected to the third transmission device 34.
Further, the upper paper feed roller 33b is driven by the second pulse motor 36 via the lower paper feed roller 33a.
be followed by. That is, the drive of the motor gear 236a of the second pulse motor 36 is transmitted via the third one-way clutch 37 to a gear 641 that drives the registration roller 38 and the pulley 140, and is further transmitted from the pulley 140 via the belt 42 to the gear 641 that drives the registration roller 38 and the drive of the motor gear 236a of the second pulse motor 36. It is adapted to be transmitted to a pulley 244 having a fourth one-way clutch 43 which drives the roller shaft 33b. However, here, the second
The driving torque of the pulse motor 36 is within the self-starting region and due to the tensile force of the paper feed roller 32, the sheet paper 3
2 is set within a range that will not be damaged.

Next, we will discuss the effect. After turning on the power, first, when the operator manually feeds the sheet paper 32, the second pulse motor 36 is rotated in the direction of the arrow s when the operator indicates manual paper feeding on the control panel (not shown). motor gear 236
a, gear 641, pulley 140, belt 42,
Pulley 244 rotates lower paper feed roller 33a in the direction of arrow t via fourth one-way clutch 43. As a result, the paper feed roller 33 is enabled to feed paper, while the registration roller 38 is kept stationary without being transmitted with the drive of the second pulse motor 36 by the third one-way clutch 37. Then, when the operator feeds the sheet paper 32 between the paper feed rollers 33 along the manual feed guide plate 13, the sheet paper 32
is fed in the direction of arrow u. However, at this time, since the driving torque of the lower paper feed roller 33a by the second pulse motor 36 is set within a range that does not damage the sheet paper 32, the operator may pull the rear end of the sheet paper 32 during paper feeding. If the torque increases due to slippage, the second pulse motor 36 will step out and the paper feed roller 33 will stop before the sheet paper 32 is damaged. However, after this, the operator releases the sheet paper 32 and the second pulse motor 3
When the torque of 6 is returned to the original drive torque, the rotation of the pulse motor 36 is automatically demodulated and the rotation of the paper feed roller 33 is changed because the drive torque is set within the self-starting range of the pulse motor 36. will be restarted and paper feeding will continue. Then, the fed sheet paper 32 is temporarily stopped by registration rollers 38, and its leading edge is aligned. During this time, the rotation of the second pulse motor 36 is switched in the direction opposite to the arrow s, and while the lower paper feed roller 33a is stopped, the registration roller 38 is driven via the motor gear 36a, the gear 641, and the third one-way clutch 37. do. As a result, the registration roller 38 moves the sheet paper 3
After conveying the sheet paper 32 in the direction of arrow w, the second pulse motor 36 is stopped to stand still, and feeding of the sheet paper 32 is completed.

Next, the case where paper is fed from the lower paper feed cassette 11, for example, will be described. When the operator selects the lower paper feed cassette 11 on the control panel (not shown) and turns on the print button (not shown), the first pulse motor 22 is rotated in the direction of the arrow x, and the motor gear 122a and the gear The lower paper feed roller 17 is rotated in the direction of arrow y via the 123 gear 226 and the first one-way clutch 24. As a result, the sheet paper 14 is taken out from the lower paper feed cassette 11 and temporarily stopped by the registration rollers 38. During this time, the first pulse motor 22 is stopped and the second pulse motor 36 is rotated in the direction opposite to the direction of the arrow s, thereby driving the registration roller 38. And the registration roller 38 is connected to the sheet paper 14.
After conveying the sheet paper 14 in the direction of the arrow w, the second pulse motor 36 is stopped to stand still, and feeding of the sheet paper 14 is completed.

Furthermore, when feeding sheet paper 15 from the upper paper feed cassette 12, operate the control panel (not shown) to rotate the first pulse motor 22 in the direction opposite to the direction of the arrow x, and rotate the upper paper feed roller 18. It will be driven.

With this configuration, when an operator manually feeds paper, there is no need to drive the paper feed roller by the main motor via a chain, spring clutch, etc. as in the past, and noise during drive is prevented, and the drive reliability is improved. Furthermore, even if the operator pulls on the sheet paper 32 during manual paper feeding, the sheet paper 32 will not be damaged, and even if the paper feed roller 33 is stopped to prevent damage, the paper will be removed as soon as the operator takes his hand off. Paper feeding is restarted, and it is possible to prevent sheet paper from being wasted and the operability is not impaired. Further, due to its structure, the paper feed roller 33 and the registration roller 38 can be driven independently from other optical devices, developing devices, etc., and it is also possible to test the paper feed section 10 alone and to make it into a unit.

Note that this invention is not limited to the above-mentioned embodiments and can be modified in various ways; for example, the drive source for driving the manual paper feed roller may be a pulse motor dedicated to the paper feed roller, rather than being used also as the drive source for the registration roller. Alternatively, the drive source may also be used as the drive source for the upper paper feed roller or the lower paper feed roller. Furthermore, the number and size of paper feed cassettes in the paper feed section are also arbitrary.

As explained above, according to this invention, by using a pulse motor to drive the manual feed roller independently from other optical devices, the chain, spring clutch, or electromagnetic clutch that was conventionally used as a drive transmission means can be used. etc., and the number of drive transmission means is reduced, which improves the reliability of the drive, prevents the noise generated by the chain, etc., and also makes it easier to unitize the paper feed section and test it independently. This also makes it possible to improve manufacturing and maintenance efficiency, as well as simplifying the internal structure of the housing. In particular, since the drive torque of the pulse motor is set within the self-starting range without damaging the sheet paper, there is no waste of sheet paper, and if the torque increases, the pulse motor will step out to prevent damage. Even if this happens, the pulse motor will be demodulated immediately once the torque returns to its original value, so operability will not be impaired. Further, as shown in the embodiment, if the pulse motor is also used as a drive source for a registration roller or the like, the number of drive sources can be reduced and costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of this invention. 10...Paper feed unit, 11...Lower paper feed cassette,
12... Upper paper feed cassette, 13... Manual feed guide plate, 17... Lower paper feed roller, 18... Upper paper feed roller, 22... Second pulse motor, 32...
... Sheet paper, 33 ... Paper feed roller, 36 ... Second
pulse motor.

Claims (1)

[Claims for Utility Model Registration] A paper feed roller 33 that pinches and conveys the sheet paper 32 that is manually inserted from the outside of the casing; a pulse motor 36 that steps out the roller 33 and automatically demodulates the paper feed roller 33 by restoring the driving torque;
A paper feeding device comprising: