JPH0592832A - Paper sheet conveying device and image forming apparatus including the conveying device - Google Patents

Abstract

(57) [Summary] [Purpose] Due to the use of forming members in the bearing,
Ground the roller shaft, which cannot be grounded at the bearing, to prevent malfunctions such as static electricity. [Structure] Shaft 103c of pickup roller 103
Since the malfunction occurs due to the accumulation of static electricity on the separation roller 1 that is already grounded to the device frame 127.
No. 04 shaft 104c is connected to the shaft 104c of the pickup roller 103 by the leaf spring 300.
Was grounded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conveying device for conveying paper sheets and an image forming apparatus equipped with this conveying device.

[0002]

2. Description of the Related Art A sheet conveying apparatus of this type includes a pickup roller for taking in a sheet and a separating roller for separating the sheets taken by the pickup roller one by one. The pickup roller and the separation roller are mounted on a conductive shaft. The shaft of the separation roller is rotatably attached to a conductive bearing portion and grounded so as to release static electricity generated when a paper sheet or the like is conveyed. By the way, the pickup roll
The roller and its shaft are provided so as to be movable up and down so as to remove the jammed document when the document is taken in. Therefore, the shaft of the pickup roller cannot be grounded.

Further, there is one in which a shaft of a separation roller is provided so as to be vertically movable so that a jammed document can be removed more easily. In this case, the shaft of the separation roller is provided. Can not even be grounded.

Further, in recent years, a forming member which is advantageous in terms of price and performance such as noise is often used as the bearing portion. Also in this case, the pickup roller shaft and the separation roller shaft cannot be grounded.

[0005]

However, if the pickup roller shaft and the separation roller shaft cannot be grounded, the static electricity generated when a paper sheet or the like is conveyed affects the control system, and the conveying device is It causes a malfunction.

Therefore, in the present invention, static electricity affects the control system even when the first and second roller shafts are movably provided and the forming member is used as the bearing portion. It is an object of the present invention to provide a paper sheet transporting device that does not include such a sheet.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides first and second rollers for conveying paper sheets, and mounting the first and second rollers, It is provided with first and second conductive shafts, one of which is grounded, and a conductive connecting member that connects these first and second conductive shafts, and also conveys paper sheets. And first and second rollers, first and second electrically conductive shafts for attaching the first and second rollers, and electrically conductive connections for connecting the first and second rollers. And a grounding means for grounding the connection member, and further has an image carrier for carrying an image and first and second rollers. An original conveying means for conveying an original to a predetermined position by a roller, and the first means.
And first and second electrically conductive shafts, one of which is grounded and the other of which is connected to the first and second rollers.
And a conductive connecting member for connecting the second conductive shaft, and image forming means for forming an image on the image carrier from the image of the original document conveyed to a predetermined position by the original document conveying means. It is characterized by

[0008]

The static electricity accumulated in one of the grounded shafts of the first and second rollers is released from the conductive connecting member through the shaft of the other roller. Also,
The static electricity accumulated on the first and second roller shafts is released from the conductive connecting member through the grounding means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment shown in FIGS. FIG. 1 is an external perspective view showing the overall configuration of a unit of a double-sided automatic electronic copying machine as an image forming apparatus according to the present invention, and FIG. 2 is a schematic vertical sectional front view thereof.

Reference numeral 60 in the figure denotes a document stacking table on which a document G in an automatic document feeding unit 3 to be described later is stacked. This document stacking table 60 is attached to the copying apparatus main body 4 of the copying apparatus unit 1.

The automatic document feeding unit 3 is adjacent to the separation unit 100, which constitutes a separation unit for feeding, separating and conveying the documents G stacked on the document stacking table 60. It is composed of a transport unit 200 that constitutes the document transport means. The separation unit 100 is
Documents to be conveyed are stacked on the document stacking table 60 to separate and reverse the documents. The transport unit 200 is provided with the document G discharged from the separation unit 100.
Is conveyed to the exposure position on the original placing table 5 of the copying apparatus unit 1, and the original G after completion of copying is ejected and placed on the original ejecting stand 201. The separation unit 100 and the transport unit 200 are independent of each other, and the transport unit 200 can be opened and closed in order to eliminate a document jam and facilitate a copy operation of a thick document such as a book. .. Further, the separation unit 100 corresponds to the copying apparatus body 4 of the copying apparatus unit 1.
Installed on top.

That is, as shown in detail in FIG. 3, the separation unit 100 constituting the above-mentioned automatic document feeding unit 3 is provided in the copying apparatus main body 4 of the copying apparatus unit 1 and the original stacking table 60 is provided at one end side. The stepped base 101 to be mounted is fixed via a mounting bracket 102, and a pickup roller 103 as a first roller and a second roller as a second roller are provided on the base 101 on the downstream side of the document stacking table 60. A separation roller 104 and a paper feed roller 105 paired with the separation roller 104 are provided, and the uppermost document G stacked on the document stacking table 60 is taken out one by one by the pickup roller 103 and conveyed to the separation roller 104. To do. A first aligning roller pair 106 is provided on the downstream side of the separation roller 104 and the paper feed roller 105 so that the original G separated by the separation roller 104 is conveyed further downstream.

A second aligning roller pair 107 is provided on the downstream side of the above-mentioned first aligning roller pair 106, and the second aligning roller pair 107 is the first aligning roller pair 107. Aligning roller pair 106
The original G conveyed from the sheet or the original G conveyed from an inversion bus mechanism which will be described later is conveyed to the side of the conveying unit 200, and the inverted sheet bus mechanism 11 is provided at the upper position thereof.
0 is provided.

The reversing paper bus mechanism 110 is provided with outer paper guides 111, 112 forming a curved paper bus path for guiding and reversing a document conveyed from a paper bus mechanism of a conveyance unit 200 described later. 113 and three inner paper guides 114, 115, 115b,
Each of these paper guides 111 to 115b is composed of three sets of conveying roller pairs 116 to 118 provided on a curved paper bus path. Each of the paper guides 111 to 115b is divided in order to improve the document jamming process and the assembling property, and each of the three pairs of transport rollers 116 to 118 has a curved paper bus transport performance. It is arranged to be sure.

Further, a gate 120 is provided on the downstream side of the above-mentioned second aligning roller pair 107, and the gate 120 conveys the paper from the separating unit 100 to the conveying unit 200 described later and the original. Paper conveyance from the conveyance unit 200 to the separation unit 100 side at the time of reversing can be switched and guided.

Further, reference numeral 121 in the drawing indicates whether or not a document is stacked on the document stacking table 60 to detect the separation unit 1.
00 to control the operation of the pickup roller 1
Document detection means provided in the same phase as 03. 122
Is a separation roller 104 that separates and feeds the originals one by one.
Is a document detection sensor installed on the conveyance path between the pair of the sheet feeding roller 105 and the first aligning roller pair 106. Reference numerals 123 and 124 denote first and first document jam detecting means installed separately on the conveying path between the first and second aligning roller pairs 106 and 107, respectively. The first document jam detecting means 123 is adapted to detect a jam of the document conveyed from the paper feed roller 105 and the first aligning roller, a document width, a document length, etc. The second document jam detecting unit 124 is configured to detect jam of the document conveyed from the first aligning roller pair 106 and jam of the document conveyed from the reversing paper bus mechanism 110.

In the figure, reference numeral 125 denotes a third document jam detecting means installed on the curved paper bus path of the reversing paper bus mechanism 110 for detecting jamming of the document to be reversed. And the separating roller 10
4. On the stepped base 101 upstream of the sheet feeding roller 105, there is provided a friction member 126 for imparting a braking action to the conveyance of the leading edge of the document G, as shown in FIG.
Reference numeral 6 is for preventing the document set on the document stacking table 60 from being fed in by multiple sheets of the separation / paper feed roller pair 104 and 105 due to the pick-up of the pickup roller 103.

Further, a document near the last document is picked up by the pickup roller 103, so that the separation / feed roller 10
As shown in FIG. 5, a friction member 126b is provided on the stepped base 101 directly below the pickup roller 103 to provide a brake for the conveyance of the lowermost original G in order to prevent the feeding of multiple originals to the Nos. 4 and 105. Is provided. The base 101 is built up so that the document does not hit the end surfaces of the friction members 126 and 126b.

By the way, the pickup roller 103 is
Are two plane portions 103a orthogonal to each other. 6 to 9, as shown in FIGS. 6 to 9, when the document G is set on the document stacking table 60, the lowered state (standby position) is maintained to suppress the leading end setting surface of the document G, The document setting phase is determined (see FIG. 6). When the copy button on the operation panel 6 is pressed in this state, the pickup roller 103, the paper feed roller 105, and the paper feed roller 1
As soon as the separation roller 104 rotated by the rotation of 05 rotates in the direction of the arrow, and the flat portion 103a is brought into contact with the original by the rotation of the pickup roller 103 and sent to the separation roller 104 (see FIG. 7). The pick-up roller 103 rises to stop the pick-up operation, while the paper feed roller 105 continues to rotate to ensure that only one taken-out uppermost document G reaches the first aligning roller pair 106. Send out (see FIG. 8). At this time, the separation roller 104 is performing normal rotation, stop, or reverse rotation. In this way, when the document G is sent to the first aligning roller pair 106, the first
The aligning roller pair 106 is rotated to feed the original document to the transport unit 200, which will be described later, and the pickup roller 103, which is the ascending first roller, starts to descend again to take out the next original document. Yes (see FIG. 9).

On the other hand, the transfer unit 200 is shown in FIG.
2, a paper bus mechanism 210 is provided, and the paper bus mechanism 210 conveys the original conveyed from the separation unit 100 to the exposure position on the original placing table 5 of the copying apparatus unit 1 and. The original after copying is conveyed to the original discharge table 201 side, or is conveyed to the reverse sheet bus mechanism 110 of the separation unit 100 in the reverse direction, and the conveying belt 211 is driven by a drive system (not shown). First and second belt rollers 212
213 and 213, four sets of pressing rollers 214 to 217 for surely bringing the conveyor belt 211 into contact with the document placing table 5 of the copying apparatus unit 1, and the document G after the copying is finished to the document discharging table 201 side. A paper guide 218 that forms a discharge path so as to guide the paper guide 2
And a discharge roller 219 that conveys and collects the document on the discharge path by the document discharge tray 201 side. Further, reference numeral 220 in the drawing denotes an original stopper for stopping the original conveyed by the conveyor belt 211 at the exposure start position on the original table 5 of the predetermined copying apparatus unit 1. An exposure unit 30 is provided on the upper side of the apparatus body 4. The exposure means 30 is provided with first and second carriages 33 and 37 that run along the original glass 5.

A light source 31 and a first mirror 32 are arranged on the first carriage 33. Second and third mirrors 35 and 36 are arranged on the second carriage 37.

A lens 34 is provided in the optical path of the reflected light of the third mirror 35, and the light passing through this lens 34 is the fourth, fifth and sixth mirrors 38, 39, 41. An image is formed on the photosensitive drum 12 via. Around the peripheral portion of the photosensitive drum 12, along the rotation direction thereof, a charging charger 13, an exposure unit 14, a developing device 15, a transfer / separation charger-16, 17, a cleaning device 18, and a charge eliminating charger are sequentially installed. 19 are provided.

Further, a conveyance path 21 for the paper P is provided in the lower part of the apparatus main body 1. On the introduction side of the transport path 21, the upper and lower paper feed cassettes 7, 8 or
A separating / conveying roller 20 ... For separating and conveying the sheets P taken in from a sheet feeding feeder 9 described later one by one is provided.

In the conveying path 21, an aligning roller 24, the transfer / separation chargers 16, 17, a conveying belt 23, a fixing device 25, and a discharging roller 26 are arranged along the conveying direction of the sheet P. Are arranged.

On the other hand, inside the carriage 2, there is provided a paper conveying means 50 used for forming an image on both sides of the paper P or for forming an image on one side by superimposing. Further, a paper feed feeder 9 for continuously feeding a large number of sheets P is provided on one side of the carriage 2.

Next, the operation of the above-described automatic document feeder according to the present invention will be described. First, when copying a single-sided document,
When the document G is set on the document stacking table 60 of the separation unit 100, this "document present" state is the document detection means 1
21 is detected. In this state, when the copy button on the operation panel 6 of the copying apparatus unit 1 is pressed, the pickup roller 103 of the separation unit 100 causes the original stacking table 6
The uppermost original document G stacked on 0 is picked up and sent to the separation / paper feed rollers 104 and 105. Then, the originals G are separated one by one by the rotation of the separation / paper feed rollers 104 and 105. It is sent to the downstream side.

Then, the original document G is placed in front of the first aligning roller pair 106, and the original document detection sensor 12 is installed.
2 is detected, after a certain period of time, the first and second
The pair of aligning rollers 106 and 107 starts rotating and sends the original to the transport unit 200 side. At this time, the first and second aligning roller pairs 106,
In synchronization with 107, the conveyance belt 211 of the conveyance unit 200 is driven, and the document sent from the separation unit 100 is driven by the conveyance belt 211 to be placed on the document stacking table 5 of the copying apparatus unit 1. The original is conveyed and stopped by the original stopper 220 at a predetermined exposure start position on the original table 5 of the copying apparatus unit 1.

The original G stopped at the exposure start position is irradiated with light from the exposure lamp 31, and the reflected light from the original G is reflected by the lens 34 through the first to third mirrors 32, 35 and 36. To the fourth lens after passing through this lens 34.
~ An image is formed on the peripheral surface of the photoconductor 12 via the sixth mirrors 38, 39, 41 to form an electrostatic latent image. This electrostatic latent image is sent to the developing device 15, where it is visualized by supplying a developer. This visible image is the paper feed cassette 7,
8 or a sheet supplied from the sheet feeding feeder 9 is transferred by the transfer charger 16. The paper on which this image has been transferred is exposed to the photosensitive drum 12 by the action of the peeling charger 17.
The sheet is separated from the sheet and is conveyed by traveling of the conveyor belt 23. This sheet is sent to the fixing device 25, where the transferred image is fixed. The paper on which this image is fixed is the output roller 2
The sheet is discharged onto the sheet discharge tray 22 via 6.

Then, the end of the copying process is judged by the signal from the copying apparatus unit 1, and when the copying operation is completed, the above-mentioned transport belt 21 is again carried out.
1 is driven, and the document table 5 of the copying apparatus unit 1 is driven.
The original document in the stationary state is discharged onto the document discharge table 201 via the paper guide 218 and the discharge roller 219 and accumulated, whereby a normal document copy is performed.

Further, in the case of a two-sided copy of an original, when the copying of the first side of the original is completed after being conveyed as in the case of the above-described one-sided original copy, the gate 120 on the separation unit 100 side switches a solenoid (not shown). At the same time that the conveyor belt 211 is released by driving, the conveyor belt 211 is driven in the opposite direction to separate the document.
Is reversed and conveyed to the reversing paper bus mechanism 110 constituting the above, the original passes on the curved paper bus path of the reversing paper bus mechanism 110, and the leading edge thereof is detected by the second original jam detecting unit 124. Then, the conveyor belt 211 is driven in the forward direction again after a lapse of a certain time in synchronization with this detection operation, and the second aligning roller pair 10 is driven.
7 starts to rotate and conveys the original document onto the original document loading table 5 of the copying apparatus unit 1, and thus the second surface, which is the back surface of the original document, is again loaded by the original document stopper 220 with the original document loading of the copying apparatus unit 1. The second copying process is performed by stopping at a predetermined exposure start position on the table 5, and when the first surface of the original is copied, the second stop process is stopped at the exposure start position. The original is re-inverted again to make a copy.

Although the automatic document feeding unit 3 uses many conveying means as described above, here, the pickup roller 103 and the separating roller 104, which are the sheet feeding portion of the separating unit 100, are used. The invention is concerned. FIG. 11 is a detailed view thereof.

In the figure, 103 and 104 are the pickup roller and the separation roller, each of which is a conductive first roller.
Pickup roller shaft 103 as a shaft of
c and the separation roller shaft 104 as the second shaft
It is arranged at both ends of c.

The separating roller shaft 104c is shown in FIG.
As shown in, the lower end of the leaf spring 126 is contacted so that the resistance to rotation is small. The upper end of the leaf spring 126 is fixed to the conductive frame 127, so that the separation roller shaft 104c is grounded.

By the way, the pickup roller 103
The pickup roller shaft 103c is provided so as to be movable up and down so as to clear the jam of the document, and is not grounded.

When a large number of originals G are continuously passed through the separation unit 100, electricity generated by friction between the originals G and the pickup roller 103 is accumulated on the pickup roller shaft 103c, and the static electricity is generated. When jumping to the frame 127, there is a problem that the control system is affected and the automatic document feeding unit 3 malfunctions.

Therefore, in the present embodiment, as shown in FIG. 12, the pick-up roller shaft 103c and the separation roller shaft 104c are made of a conductive material having a length so as to reduce the influence on the rotation. They are connected by a conductive leaf spring 300 (see FIG. 12) formed in a substantially S-shape as a connecting member.

Therefore, the static electricity accumulated on the pickup roller shaft 103c is the conductive leaf spring 300, the separating roller shaft 104c, and the conductive leaf spring 12.
6 is released to the conductive frame 127 via 6, and the malfunction of the automatic document feeding unit is prevented.

The present invention is not limited to the above embodiment,
When the pickup roller 103 and the separation roller 104 are both movable up and down due to a jammed document, it is difficult to prevent static electricity as described above. Therefore, as shown in FIG. You may ground by fixing one end part of the conductor wire 302 which comprises a grounding means by screwing or fitting, and fixing the other end part to the said conductive frame 127.

Further, according to the present invention, as shown in FIG. 13, when only the pickup roller 103 moves up and down for clearing the jam of the document, instead of the above-mentioned conductive leaf spring 300, a coil spring for pulling with an appropriate weight is used. The pickup roller 103 may be grounded by hooking 301 between the pickup roller shaft 103a and the separation roller shaft 104c like the leaf spring 300.

[0040]

As described above, according to the present invention, static electricity accumulated on one of the shafts of the first and second rollers is transferred to the shaft of the other roller through the conductive connecting member. The static electricity that flows and escapes, and the static electricity accumulated on the first and second shafts escapes from the conductive connecting member via the grounding means.

Therefore, even if the first and second rollers are provided so as to be movable up and down, and the molding member is used as the bearing portion, the control system is controlled by the static electricity generated when the paper sheet is conveyed. This has the effect of preventing malfunction.

[Brief description of drawings]

FIG. 1 is a perspective view showing an image forming apparatus which is an embodiment of the present invention.

FIG. 2 is a vertical sectional view showing the image forming apparatus of FIG.

3 is a cross-sectional view showing a sheet feeding unit of the image forming apparatus of FIG.

FIG. 4 is a cross-sectional view showing a document stacking unit of the paper feeding unit of FIG.

5 is a cross-sectional view showing a document stacking unit of the paper feeding unit of FIG.

FIG. 6 is an explanatory view showing a paper take-out operation by a pickup roller of the paper feed section of FIG.

FIG. 7 is an explanatory view showing a paper take-out operation by a pickup roller of the paper feed section of FIG.

FIG. 8 is an explanatory view showing a sheet taking-out operation by a pickup roller of the sheet feeding section of FIG.

FIG. 9 is an explanatory view showing a sheet taking-out operation by a pickup roller of the sheet feeding section of FIG.

10 is a vertical cross-sectional view showing a transport unit of the image forming apparatus in FIG.

11 is a perspective view showing a mounting structure of a pickup roller and a separation roller of the paper feeding unit of FIG.

12 is a side view showing a state in which the shaft of the pickup roller of FIG. 11 and the shaft of the separation roller are connected by a connecting member.

FIG. 13 is a side view showing a first other embodiment of the present invention.

FIG. 14 is a side view showing a second embodiment of the present invention.

[Explanation of symbols]

103c ... 1st shaft, 104c ... 2nd shaft, G ... Original document (paper sheet), 103 ... Pickup roll (first roller), 104 ... Separation roller (second roll)
La), 300 ... Leaf spring (connecting member), 302 ... Conductive wire (grounding means).

Claims (3)

[Claims] 1. A first and second roller for conveying paper sheets.
And a first and second electrically conductive shaft to which the first and second rollers are attached and one of which is grounded, and an electrically conductive layer which connects the first and second electrically conductive shafts. And a flexible connection member. 2. A first and second roll for conveying paper sheets.
La, first and second electrically conductive shafts to which these first and second rollers are attached, electrically conductive connecting members for connecting these first and second rollers, and this connecting member And a grounding unit for grounding the paper sheet. 3. An image carrier for carrying an image, and first and second rollers, wherein the first and second rollers are provided.
A document transporting means for transporting a document to a predetermined position by means of a roller, first and second conductive shafts to which one of the first and second rollers is attached and one of which is grounded, A conductive connecting member for connecting the first and second conductive shafts; an image forming means for forming an image on the image carrier from an image of the original document conveyed to a predetermined position by the original document conveying means; An image forming apparatus comprising: