JPS6221691B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning device for a rotating paper feeding member such as a paper feeding roller in a paper feeding device.

Electrophotographic copying machines, offset printing machines, and similar machines include a sheet feeder for feeding sheets, such as transfer sheets or printing sheets, to a destination location. This paper feeding device, for example, can be configured by stacking a large number of sheets on a paper feeding table, placing a paper feeding roller in contact with the upper surface of the uppermost sheet among these sheets, and rotating this roller. It is well known that a paper feeding system in which the topmost sheet is fed is already commonly used.

In the above-described sheet feeding system, the uppermost sheet is separated from the next sheet by the rotating action of the sheet feeding roller and the separating action by a suitable means such as a corner separator, and is sent to the destination position. In this case, the sheet is fed out by the friction between the paper feed roller and the sheet that is in contact with it. Conditions such as the smoothness and coefficient of friction of the circumferential surface of the sheet, and the state of dust adhesion greatly influence the reliable feeding of the sheet.
Even if the above-mentioned smoothness, coefficient of friction, etc. are taken into consideration from a design or workmanship perspective, it is difficult to prevent the adhesion of dust, etc.

This is a common problem in devices such as electrophotographic copying machines and offset printing machines that have this type of paper feeding device, but this point will be discussed below using a double-sided copying machine as an example. I'll decide. FIG. 1 shows an example of an electrophotographic copying machine capable of so-called double-sided copying, in which different copy images can be obtained on both the front and back sides of a single transfer sheet. In the figure, first, the peripheral surface of the photosensitive drum 1 rotating in the direction of the arrow is charged by the charging device 2, and an electrostatic latent image corresponding to the document on the document table 3 is formed by the exposure optical system. It is formed. This latent image is visualized by the developing device 4, and this image is further transferred onto the transfer sheet S sent out from the paper feed tray 5. After the transfer sheet S is fixed by the fixing roller 7, it is once placed on the intermediate paper feed table 8.

A copy image has already been formed on the front surface of the sheet S placed on the intermediate sheet feed tray 8 on the side of the sheet feed roller 9, and this sheet S is rotated in the direction of the arrow by the sheet feed roller 9. As a result, the sheet is sent toward the photoreceptor drum 1 via the intermediate sheet path 11. Then, a visible image on the circumferential surface of the drum corresponding to a different document is transferred to the back side of the transfer sheet S, and
After being fixed, the sheet S passes through the discharge path 12.
The paper is then discharged onto the paper discharge tray 13.

Here, the paper feeding action on the intermediate paper feeding table 8 is particularly problematic. That is, developing toner, dust, and fine paper particles that were originally attached to the transfer sheet adhere to the circumferential surface of the paper feed roller 9, and this causes slips between the sheet and the sheet, causing the paper to be fed. There is a risk that the action will not be performed smoothly. On the other hand, if these deposits adhere to the transfer sheet and are sent as they are to the transfer drum again, there is a risk that the copying function will be impaired. Regarding such defects, especially the former point, a common problem also occurs in the paper feed roller 6 on the lower side. Furthermore, this problem is common not only to electrophotographic copying machines having this type of paper feeding device, but also to offset printing machines and other devices.

An object of the present invention is to provide a peripheral surface of a rotating paper feeding member such as a paper feeding roller to ensure a smooth and reliable paper feeding action.
An object of the present invention is to provide a cleaning device that can be maintained in a clean state.

The present invention will be explained below with reference to illustrated embodiments.

Although FIG. 2 shows an embodiment of the apparatus of the present invention, for convenience, the paper feeding device 14 for intermediate paper of the double-sided copying machine shown in FIG. shall be applied. That is, in the figure, the paper feed roller 9 is placed with a predetermined pressure on the top surface of the topmost sheet among the plurality of sheets placed on the paper feed table 8, and is driven by a drive mechanism (not shown). It rotates by a predetermined angle in the direction of the arrow at the appropriate time and sends out the sheets one by one in the direction of the arrow. Note that the number of sheets on the paper feed table 8 may be one instead of a plurality. The paper feed roller 9 can move toward and away from the top surface of the sheet by swinging both supports 17 and 18 around a shaft 16, and comes into contact with the top surface of the sheet during paper feeding. At other times, it is separated from the sheet as shown by the imaginary line in FIG.

Above the paper feed roller 9, a cleaning member, ie, a cleaning belt 20 made of rubber, felt, cloth, or the like, is arranged parallel to the axial direction of the paper feed roller 9. The cleaning belt 20 is stretched between both pulleys 21 and 22, and a gear 24 is fixed on a shaft 23 to which one of the pulleys 22 is fixed. A cog belt 27 having rack-shaped teeth formed on the inside is stretched between the gear 24 and a gear 25 fixed to the shaft 26a of the drive motor 26. Here, as described above, during paper feeding, the paper feed roller 9 contacts the top surface of the sheet and rotates at a predetermined angle in the direction of the arrow to feed the sheet.
After completing this operation, both support arms 17, 18
is rotated counterclockwise about the shaft 16 in FIG.

The cleaning belt 20 is constantly rotated in the direction of the arrow by the drive action of the drive motor 26 via the cog belt 27, or the cleaning belt 20 starts rotating at the same time as the paper feed roller 9 comes into contact with the belt 20. . Therefore, at the same time as the paper feed roller 9 contacts the belt 20, the portion of the belt 20 that contacts the circumferential surface of the roller 9 moves in a direction perpendicular to the rotational direction of the roller 9 and moves toward the roller 9.
The sheet slides into contact with the peripheral surface of the sheet and attracts developing toner, dust, fine cut debris from the sheet, etc. adhering to the peripheral surface, thereby keeping the peripheral surface clean. In FIG. 2, the dust or developing toner may be collected by a separator 28 disposed at a position on the surface of the belt 20, and a cleaning agent supply device may be provided above the cleaning belt 20. Alternatively, a cleaning liquid such as alcohol or trichloride may be applied or dropped. Further, the cleaning belt 20 may have a configuration in which the surface portion of the belt made of a flexible material is treated with flocking to form a brush shape.

FIG. 4 shows another example of a paper feeding device, and while the conventional rotating paper feeding member is a paper feeding roller having a full circumferential surface, the rotating paper feeding member 37 of this device is It has a hook shape and has an arcuate partial circumferential surface 37a that is in contact with the upper surface of the sheet. Same member 3
7 has a predetermined width in the axial direction of the shaft 36 to which the base is fixed, and a plurality of the shafts 7 are arranged on the same shaft 36. Then, each rotation feeds out a sheet one by one, and when the sheet feeding operation is completed, it rotates to the position shown by the imaginary line, and during this rotation, it operates in the same way as the cleaning belt of the above-mentioned embodiment. By the constructed cleaning belt 38, the partial circumferential surface 3
7a is cleaned.

In this way, in the apparatus of the present invention, the circumferential surface of the rotating paper feeding member such as the paper feeding roller can be kept clean, so that the frictional feeding action of the sheet can be performed smoothly and reliably. In addition, these cleanings can be performed while the machine is running without stopping the machine, and if the cleaning process is incorporated into the machine's operation program, the cleaning can be done automatically and periodically. You can make it happen. Note that the present cleaning device may be kept in an operating state all the time, but it may also be operated intermittently, in which it is kept in an inoperative state all the time and becomes an operating state when a certain number of sheets have been fed. In addition, in each of the above-mentioned embodiments, a paper feeding device of a double-sided copying machine was applied.
Even ordinary single-sided copying machines are equipped with this type of paper feeding device and may be used to perform double-sided copying, so if this cleaning device is included, it will be extremely advantageous in ensuring more reliable paper feeding. It is.
Further, the present invention can also be applied to a printing paper feeding device used in an offset printing device, a plate feeding device for a sheet-like original plate, and the like. In addition, in the apparatus of the present invention, the rotary sheet feeding member, which is the object to be cleaned, is placed at a position where it contacts only the sheet during paper feeding, and at a position where it contacts only the cleaning member during cleaning.
The position of the rotating paper feeding member can be determined depending on the time of paper feeding and cleaning. During paper feeding, the rotating paper feeding member is kept in a position away from the cleaning member, so the rotating paper feeding member is No load is generated in the rotation of the paper feeding member.

As described above, according to the present invention, there is provided a cleaning device that can maintain the peripheral surface of a rotating paper feeding member such as a paper feeding roller in a clean state, so that the paper feeding operation can be made smooth and reliable.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an example of a double-sided copying machine equipped with a paper feeding device, which is an application example of the present invention, and FIG. 2 is a perspective view showing an example of a cleaning device for a paper feeding roller in the paper feeding device. FIG. 3 is a side view of the same apparatus as described above, and FIG. 4 is a side view of a cleaning device for a rotary paper feeding member in yet another paper feeding device. 9, 37... Rotating paper feeding member, 20, 38... Cleaning member.

Claims (1)

[Claims] 1. A rotary sheet feeding member having a full circumferential surface or a partial circumferential surface is provided, and a portion of the full circumferential surface or partial circumferential surface of the rotary sheet feeding member is applied to sheets stacked on a sheet feeding tray. In the paper feeding device, the sheet is fed by rotating the rotating paper feeding member, the paper feeding device is configured to feed the sheet by rotating the rotating paper feeding member, while the sheet is in sliding contact with the entire circumferential surface or a partial circumferential surface of the rotating paper feeding member. A cleaning member is provided which cleans the circumferential surface by continuously moving in a direction that makes contact with the circumferential surface different; A rotary paper feeding member characterized in that the rotating paper feeding member can be positioned in a position where it contacts only the sheet when paper is being fed and a position where it is in contact only with a cleaning member when cleaning, depending on the time of paper feeding and cleaning. cleaning equipment.