JPH0412468B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copy paper conveyance device for a copying machine that accurately conveys copy paper while preventing wheel marks caused by transferred toner from becoming large.

As a conventional copy paper conveying device for a copying machine, there is, for example, the one shown in FIG. Some machines are equipped with a drive roll 4 and a star wheel (idle) 5 provided between the drive roll 4 and the star wheel (idle) 5, with the transferred copy paper being held between the drive roll 4 and the star wheel 5.
The driving force is used to transport the image to the fixing section 3.

According to this copy paper conveying device for a copying machine, by making the diameter of the star wheel 5 as small as possible, the length l of the wheel mark shown in FIG.
(A and B show copy images made of transferred toner, and dotted line wheel marks made of transferred toner are formed in non-image areas) are made smaller.

However, according to the conventional copy paper conveying device for a copying machine, when the diameter of the star wheel 5 is made small, if the copy paper 6 curls at the leading edge, as shown in FIG. Since the copy paper 6 cannot be held properly between the two, there is a possibility that the copy paper cannot be transported properly.

The present invention has been made in view of the above,
In order to accurately convey the copy paper while preventing wheel marks caused by transferred toner from becoming large, a guide wheel is provided that has a diameter larger than the diameter of the conveyance wheel that contacts the transfer surface of the copy paper, and whose wheel surface does not contact the transfer surface. The present invention provides a copy paper conveyance device for a copying machine in which the conveyance wheel and the conveyance wheel are arranged side by side.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The copy paper conveying device for a copying machine according to the present invention will be described in detail below.

Figure 2 A, B, and C show an embodiment of the present invention,
A platen 11 and a console 12 are provided at the top of the copying machine main body 10. A document 13 is placed on the platen 11, and the console 12 includes a start switch, a magnification selection switch, and a magnification selection switch (not shown).
A copy number display section and the like are provided. Below the platen 11 are a lamp 14, mirrors 15, 16,
A scanning system consisting of a mirror lens 17 and a mirror lens 18 is provided, and a photosensitive drum 1 is also provided which is exposed to light through an exposure slit 19 by the scanning system. Around the photoreceptor drum 1, there is a charging section 20 that charges electricity prior to exposure, a developing section 21 that develops a latent image caused by exposure, a transfer section 2 that transfers the developed image onto copy paper, and a transfer section 2 that removes residual toner after transfer. A cleaner section 22 is provided for removal. Paper feed trays 23 and 24 are provided at the bottom of the copying machine main body 10 to feed paper by paper feed rolls 23a and 24a, and the above-mentioned drive wheel 4 is provided between the transfer section 2 and the fixing section 3. In addition to the star wheel 5, a guide wheel 25 is provided (supported by a support rod 26) which has a larger diameter than the star wheel 5 and has a wheel surface that does not contact the transfer surface of the copy paper. The copier mentioned above has a microcomputer of 27
The operation is controlled by This microcomputer 27 has an input interface for inputting sensor signals from various sensors provided in the main body 10 and operation signals from the console 12, a ROM for storing a program for processing input signals, and a ROM for processing signals based on the program. A CPU, a RAM that temporarily stores the CPU's signal processing results and data, and a console that outputs control signals based on the CPU's signal processing results.
2 and an output interface for controlling various control objects of the main body 10.

To explain the operation in the above configuration,
After placing the original 13 on the console 11 and selecting the copy paper size from the console 12, turning on the start switch (not shown) on the console 12, a series of operations (original scanning, charging, exposure, development, paper feeding, etc.), and is transferred to copy paper in the transfer section 2. Even if the leading edge of the copy paper is curled as shown in FIG.
It is fed into the gap between the star wheel 5 and the star wheel 5, is held between the two, and is transferred to the fixing section 3. The guide wheel 25 may be idle, but by driving it, the effect of guiding the copy paper can be enhanced.
In this case, since the diameter of the guide wheel 25 is often larger than the diameter of the drive wheel 4, the guide wheel 25 is guided by the rotational speed of the drive wheel 4 so that the circumferential speeds of the two are approximately equal to reduce the influence on the copy paper. It is preferable to reduce the rotational speed of the wheel 25 according to the ratio of the diameters.

As explained above, according to the copy paper conveyance device for a copying machine according to the present invention, the guide wheel has a diameter larger than the diameter of the conveyance wheel that contacts the transfer surface of the copy paper, and whose wheel surface does not contact the transfer surface. Since it is placed side by side with the conveyance wheel, the copy paper can be conveyed accurately while preventing wheel marks caused by transferred toner from becoming large.

[Brief explanation of drawings]

FIG. 1A is an explanatory diagram showing a conventional copy paper conveying device. FIG. 1B is an explanatory diagram showing wheel marks.
FIG. 2A is an explanatory diagram showing one embodiment of the present invention. Second
Figure B is an enlarged view of the main part of Figure 2 A. Figure 2C is a side view of Figure 2B. Explanation of symbols, 1... Photosensitive drum, 2... Transfer section, 3... Fixing section, 4... Drive wheel, 5
... Star wheel (conveyance wheel), 6 ... Copy paper, 10 ... Main body, 11 ... Platen, 1
2...Console, 13...Document, 14...Lamp, 15, 16, 17...Mirror, 18...Lens mirror, 19...Slit, 20...Charging section,
21...Developing section, 22...Cleaner section, 23,2
4... Paper feed tray, 25... Guide wheel, 26
...Support rod, 27...Microcontroller.

Claims (1)

[Scope of Claims] 1. A rotating member having a predetermined diameter and in contact with the transfer surface of the copy paper, and a drive that clamps the copy paper in the opposing gap between the rotating member and transports the copy paper in the ejection direction. In the copy paper conveying device including a roll, the rotating member has a diameter larger than the diameter and a circumferential surface that does not contact the transfer surface of the copy paper, and the circumferential surface guides the copy paper to the opposing gap. A copy paper conveyance device for a copying machine, characterized in that a guide rotation member is arranged side by side.