JPS5851858B2 - Sheet feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a feeding device for feeding sheets such as paper in a copying machine, etc., and is capable of accurately and easily detecting jamming.

Conventionally, sheet jamming detection devices have several detection sections such as microswitches, and when a sheet passes through the detection sections, a timer is activated, and if the sheet does not pass the next detection section after a certain period of time, the timer is activated. This caused a time-up, which was judged to be jamming, and operations such as sheet feeding were stopped.

However, in this case, even if jamming occurs, it cannot be detected until a certain period of time has elapsed, and countermeasures may be delayed, causing the jamming to progress and damage the device.

Also, if jamming occurs after passing through the detection section,
Jamming is not detected.

In addition, if a long sheet is fed, the jamming detection method described above cannot detect it at all.

The present invention eliminates the above-mentioned drawbacks and provides a device for accurately detecting the occurrence of jamming, and an embodiment thereof will be described below.

In the drawings, 1 is a side plate, and 2 and 3 are bearings attached to the side plate 1, which receive rollers 4 and 5.

The roller 4 is pressed against the roller 5 by a presser plate 6 and a presser spring 7.

Reference numeral 8 denotes a drive gear, which is connected to a drive source such as a motor (not shown) via a clutch or the like.

9 is a driven gear, 10 is a friction plate fixed to roller 5,
Since the driven gear 9 and the friction plate 11 are held down by the friction plate pressing spring 12, the driven gear 9 and the friction plate 10.1
1, a frictional force is generated between the two.

The driving force transmitted to the driven gear 9 by this frictional force is transmitted to the roller 5, and the sheet 13 sandwiched between the rollers 4 and 5 is conveyed.

14 is a circular plate with a hole attached to the shaft end of the roller 5, and rotates together with the roller 5.

Reference numeral 15 denotes a light emitter/receiver provided across the disc 14. When the sheet 13 is being conveyed normally, the rollers 4 and 5 rotate at a specified number of rotations, so from the light emitter/receiver 15, It is configured to generate a signal with a specified period.

16 is a screw for adjusting the frictional force of the friction plates 10 and 11.

In the apparatus configured as described above, if the sheet 13 jams, a large load will be applied to the roller 5, and if the load exceeds a certain level, the driven gear 9 and the friction plate 10.
1, and the roller 5 stops rotating.

Therefore, the disk 14 also stops rotating, and the light emitter/receiver 15 no longer generates a signal with a specified period.

In this way, when a signal with a specified period is not emitted from the light emitter/receiver 15, it is determined that jamming has occurred, and the jamming is indicated by stopping the device and displaying the display.

The friction force between the driven gear 9 and the friction plates 10.11 may be appropriately adjusted and set using the adjustment screw 16.

Although the rotation detector consisting of the light emitter/receiver 15 and the disk 14 described in the above embodiment uses light, there is also a magnetic rotation detection method using a magnet and a reed switch or a Hall element. You can also use a container.

As is clear from the above embodiments, the present invention has the effect of reliably detecting jamming because jamming is detected by the rotation of the roller that conveys the sheet.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a sheet feeding device according to an embodiment of the present invention, and FIG. 2 is a front view of the main parts thereof. 4.5...roller, 9...driven gear,
10, 11... Friction plate, 12... Pressing spring, 14... Disc plate, 15... Light emitter/receiver, 16... screw.

Claims (1)

[Claims] 1 a first roller supported rotatably; a second roller pressed against the first roller by a presser spring;
Pressing the driven gear against the friction plate via a first friction plate fixed to the first roller, a driven gear rotatably supported by the first roller, and a second friction plate. A spring member, a drive gear that meshes with the driven gear, a drive source that drives the drive gear, a disc having a plurality of holes formed therein and attached to the roller, and a disc provided between the discs. A sheet feeding device comprising a light emitter and receiver.