JPS638159A - Paper conveyor - Google Patents

Abstract

PURPOSE:To keep off any slip and separation of paper as well as to secure a good picture in quality, by installing a paper guide, making the paper adhere to a sensitizer drum, movably up and down in a part before and behind the transfer corotion installed in correspondent to the sensitizer drum. CONSTITUTION:A front end of paper 2 is held by a gripper 5, conveying it in an arrow A direction by a chain 7, and a toner image is transferred onto it from a sensitizer drum 1 by a transfer corotron 10 at a part in contact with the sensitizer drum 1. Paper guides 11 and 13 are installed in front and in the rear of this transfer corotron 10, and when the gripper 5 on the paper 2 is passed through there, these paper guides 11 and 13 are made to go up by solenoids 10 and 12, thus the paper 2 is stuck close to the sensitizer drum 1. The transfer corotron 10 is also made to go up at the same time. The gripper 5 releases the paper 2 automatically when it comes to a part of a sprocket 8. With this constitution, a slip in the paper 2 and its separation are prevented from occurring, and a good quality image is transferred.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a paper conveyance device used in copying machines or laser printers, etc., and in particular, to a paper transport device configured to prevent rapid movement of paper in the image transfer area. The present invention relates to a paper conveying device formed by:

(Prior Art) In devices such as copying machines, a transport port-ra device is often used as a device for transporting paper. This conveyance roller device is composed of a drive roller and a binding roller, and is designed to convey paper while sandwiching it from above and below. Multiple sets of conveyance port-roller devices are installed in the paper conveyance path. , the paper is moved.

Separately, a chain is placed along the paper transport path,
Grippers are provided on the chain at predetermined intervals, the front end of the paper is held in a pinched state by the holder of the gripper, and the paper is prevented from moving as the chain moves,
A device is also used in which the paper is transported along a path from the paper tray through the image transfer section to the reading tray.

Gripper driven by a chain as described above
For example, there is a device using this as shown in FIG. In this device, a chain 7 is disposed along a paper conveyance path, and bi-neem transports 1 and 20 are provided at the paper discharge side end of the paper conveyance path.

The vacuum transport 20 is provided at the end of the paper transport path to transport the paper from the release part to the output tray when the paper 2 is released from the gripper 5. This is usually a suction device 2.
3 and a belt 21 are used.

Further, a transfer roller 1-ron 10 is provided corresponding to the image transfer portion of the photosensitive drum 1, and the transfer corotron 10
A paper guide 11 for pushing up the paper 2 toward the photoreceptor drum 1 is provided in the front part.

This Freon 1 to paper guide 11 is connected to the solenoid 12
When the gripper 5 passes the lower surface of the photoreceptor drum 1, the front paper guide 11 is lowered so as not to hinder the passage of the gripper. , when transferring the toner IS, push up the freon 1 to vapor guide 11,
The transfer corotron and paper 2 are brought into contact with the surface of the photosensitive drum 1.

In other words, in such a device, the reason why the paper guide is moved up and down is that the thickness of the gripper is larger than the distance between the transfer roller and the photoreceptor drum. Alternatively, such a structure is used to prevent collision with the paper guide.

(Problems to be solved by the invention) However, in the conventional device as described above,
After the gripper passes the bottom surface of the photoreceptor drum, the leading edge of the paper reaches Vacuum I/Lanceport 1 while the paper guide is pushed away and images 1 to 1 are being transferred. When the paper is attracted by the force suction device, a phenomenon may occur in which the leading edge of the paper is suddenly pulled.

Therefore, due to this action, the paper may be peeled off from the image transfer area or the surface of the photoreceptor drum may be scratched (
Unfavorable conditions such as smear (hereinafter referred to as smear) may occur. First, while the leading edge of the paper is moving at a constant speed along the chain, it is suddenly sucked by the vacuum transport, causing the paper to become curved, causing the paper to be stretched by that amount. By being given.

The occurrence of the above-mentioned smear also causes blurred areas in some parts of the copy, resulting in deterioration of the image quality of the bee.

(Object of the Invention) The present invention solves the above-mentioned drawbacks of the conventionally used devices. Even when the leading edge of the paper is pulled by the suction force of the vacuum transport, the paper does not suddenly touch the paper. The purpose is to provide a device that can prevent movement from occurring.

(Means and effects for solving the problems) The paper conveyance device of the present invention is driven by a chain and is composed of a gripper for holding the front end of the paper and conveying it, and a vacuum transport. In the device that
This device is characterized in that paper guides are provided at the front and rear portions of a transfer corotron provided corresponding to the photosensitive drum to bring the paper into close contact with the surface of the photosensitive drum.

In the paper conveyance device of the present invention, the transfer roller (
~Front paper guides on the front and rear parts of Ron 17
- a paper guide is provided, and the paper is securely brought into close contact with the surface of the photoreceptor drum by the two paper guides;
In addition to transferring the toner image, the paper is reliably held in close contact with the surface of the photosensitive drum even when it is sucked by the vacuum 1 to transport.

Therefore, smear does not occur in the image transferred to the paper, and the image quality of the copy is prevented from deteriorating.
It becomes possible to obtain clear copies.

<Example> According to the illustrated example, a paper conveyance device 2I (
The L configuration will be explained.

As shown in FIGS. 1 and 2, in an apparatus such as a copying machine that transfers an L-sheet image onto a sheet of paper to form a bead, the apparatus of the present invention has a transfer unit of 1 tron 10. A front paper guide 1 to a paper guide 11 and a rear paper guide 13 are provided in the front and rear parts, and these paper guides are respectively moved up and down by solenoids 12 and 17I.
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The front paper guide 11 and the rear paper guide 13 are formed as long members in the width direction of the paper 10, as shown in FIG. Press the entire area toward the bottom surface to ensure that it comes into close contact with the image transfer area.

Furthermore, in this embodiment, the transfer corotron 10 is
It is mounted on a vertical movement device (not shown) so that it is held up when images 1 to 1 are transferred, and is lowered when the gripper 5 passes through.

In the case of the present invention, the conveyance device disposed along the paper conveyance path of a copying machine includes grippers 5 provided on a chain 7 at predetermined intervals, and holders attached to the grippers 5 at predetermined intervals. 6 and hang it on the boulder 6 so that it can hold the leading edge of the paper. With the gripper 5 holding the tip of the M10, the chain 7 is moved along the paper conveyance path as it is driven by the sprocket 8 or another sprocket.

Further, a device for releasing the gripping state by the holder 6 is provided at the end of the paper conveyance path, that is, at the sprocket 1-8 in the embodiment, and when the gripper 5 reaches the sprocket 80, , the paper is automatically released.

The bucket comb 1 to transport 20 of the present invention use a device having the same configuration as the bucket comb transport that has been used conventionally, and a fan 23 etc. is installed inside the bar 4-comb chamber. A suction force generating device is provided, and suction holes 22 are provided at predetermined intervals on the top surface of the chamber.
is formed, and air is sucked through the suction hole 22.

Furthermore, on the upper surface of the chamber, there are multiple bells 1 to 21.
．． 21... are arranged, and the belt 21 is driven at the same speed as the chain 7.

Then, the paper 2 held by the gripper 5 is sucked and conveyed together with the chain, and at the release point of the holder 6,
After the conveyance state by the gripper is released, the vacuum transport 20 continues conveying the paper and moves the paper toward the discharge tray.

Next, the operation of the paper conveyance device of the present invention will be explained.

The paper 2 supplied from a paper feed device such as a paper tray is driven by a chain 7 and transported with its leading end held by a gripper 5. Then, the toner image passes through the lower surface of the photoreceptor drum 1 in a state in which the timing coincides with the toner image formed on the surface of the photoreceptor drum 1.

In that case, transfer roller] ~ Ron 10. The front paper guide 1 to the paper guide 11 and the rear paper guide 13 are each waiting in a lowered state by a solenoid so that they do not obstruct the passage of the gripper 5.

When the gripper 5 has finished passing the lower surface of the photosensitive drum 1, the solenoid is applied by the output from the control device or the detection device, and the transfer column 10. Front paper guide 11, rear paper guide 13
-4, the paper 2 is brought into contact with the surface of the photosensitive drum 10, and the toner image is transferred by discharge from the transfer corotron.

When the gripper 5 reaches the upper surface of the vacuum transformer 1-20 during the above-described transfer, the leading end of the paper 2 is attracted by the vacuum transformer, and its front end is rapidly pulled.

However, in the paper conveyance device of the present invention, the number of pages
= - Bar guides are installed on both sides of the transfer corotron 10, and even if the paper 2 is sucked by the vacuum transport 20 due to the frictional resistance between the paper 2 and the rear paper guide [! After the paper 2 has advanced some 41 steps without coming off the drum surface or slipping, the natural slack of the paper causes it to come into contact with the bell 21 and carry out its conveyance.

Therefore, in the apparatus of the present invention, even if the paper is sucked by the vacuum transport 20, the speed of the paper can be prevented from increasing instantaneously, and the image quality of the copy can be prevented from deteriorating.

Furthermore, in the apparatus of the present invention, instead of moving the transfer corotron, front paper guide, and rear paper guide up and down separately as described above, as shown in FIG. It is also possible to use In this case, a front paper guide 11 and a rear paper guide 13 are provided on both sides of a strip 11 and a corotron 10 provided corresponding to the center of the lower surface of the photoreceptor drum.
These are provided on a frame 15, and the frame 15 is moved up and down simultaneously by a solenoid 16.

Therefore, when the device shown in FIG. 3 is used, it is possible to reduce the number of actuating members, making it easier to control their operations.

In the above-described embodiments of the present invention, the paper guide may be a member formed by curving a plate-like member as shown in FIG. 1, or a cylindrical member as shown in FIG. However, it is necessary to use a member that allows the coefficient of friction of the paper to be set to an appropriate value and that does not cause sudden movement of the paper even when the paper is sucked by a vacuum transport. Specifically, the perbar guide is made of synthetic resin such as vinyl chloride.

Furthermore, as a driving member for vertically moving the transfer corotron, front paper guide, and rear paper guide, other driving devices can be used in addition to the above-mentioned mutual direction type solenoids. , its drive is by commands of the copier control station, or
A sensor installed at a predetermined location on the paper conveyance path detects the passage of the gripper, and the detection can be performed based on the output.

(Effects of the Invention) Since the paper conveying device of the present invention has the above-described configuration, when the paper is sucked by the vacuum transport, the speed of paper movement is prevented from increasing rapidly. In particular, since the toner image transfer section 4 does not cause the paper to peel off or slip, it is possible to obtain copies of good image quality without smearing.

In addition, in the paper conveying device of the present invention, the paper guides provided on both sides of the transfer corotron set the paper in good contact with the photoreceptor drum, so that the paper is in good contact with the photoreceptor drum. Contact with the drum is ensured, and the toner image can be transferred accurately.

[Brief explanation of drawings]

FIG. 1 is a side view showing the configuration of a paper conveying device according to the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a side view showing the configuration of another embodiment of the present invention, and FIG. 4 is a conventional FIG. 2 is a side view showing the configuration of a paper conveyance device that is more commonly used. Reference numerals in the figure 1...Photosensitive drum, 2...Paper, 5
...Gripper-16...Holder, 7
...Chain, 8...Sprocket,
10...Transfer corotron, 11...Front paper guide, 12...Solenoid,
13... Rear paper guide, 14...
... Solenoid, 15 ... Frame, 20 ...
... Hakim transport, 21 ... Belt, 22 ... Suction hole, 23 ... Fan.

Claims (1)

[Claims] In a conveyance device that is driven by a chain and is composed of a gripper for holding and conveying the front edge of paper, and a vacuum transport, the front and rear of the transfer corotron provided corresponding to the photoreceptor drum are A paper conveying device characterized in that a paper guide is provided in a portion of the paper guide for bringing the paper into close contact with the surface of a photoreceptor drum.