JPH03172238A - Paper form delivery device of paper feeder - Google Patents

Abstract

PURPOSE:To surely separate double-fed paper forms by providing a drive-control means which drive-controls a pickup member in such a way that the pickup member is rotated, when a paper form is delivered, and a paper form contact part is detached from a paper form staying in a paper form storage part and placed in a refuge-taking posture when the paper form is not delivered. CONSTITUTION:When a paper form is delivered, a pickup member 20 is rotated by a drive-control means. Then the paper form contact part 22 of the pick up member 20 is brought into contact with the upper face of the paper form in a paper form storage part 4 and elastically deformed. When the pickup member 20 is further rotated from this condition, a paper form 35 is taken out from the paper form storage part 4 and fed to the side of a conveying roller 30 and a reverse roller 31 by repulsive force and friction force of its elastic deformation part. At the time of delivery of this paper form, the reverse roller 31 is reversely rotated in the case of double-feeding the paper, and double-fed paper form 36 tends to be returned to the side of the paper storage part 4. Then, the paper form contact part 22 of the pickup member is detached from the paper form in the paper form storage part 4 by the drive-control means, so that the double-fed paper form 36 is returned to the side of its storage part.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has a paper feeding device, in particular, a conveyance roller and a reverse roller, and prevents double feeding of paper from a paper storage section to a paper receiving section. The present invention relates to a paper feeding device of a paper feeding device for feeding paper.

[Conventional technology]

For example, an image processing apparatus such as a copying machine or a laser printer is provided with a paper feeding device for supplying paper to an image forming section. As this paper feeding device, FRR (Fe
ed and Reverse Roller)
method has been adopted.

This FRR type paper feeding device consists of a conveyance roller for conveying the paper in the paper storage section to the image forming section, a reverse roller arranged opposite to the roller surface of the conveyance roller, and a reverse roller arranged above the paper in the paper storage section. It includes a rotatably provided pickup roller.

The reverse roller rotates as a result of the conveyance roller when the paper is conveyed, and rotates in the same direction as the conveyance roller when the sheets are double-fed to separate the double-fed sheets and prevent double-feeding of the sheets to the image forming section. Further, the pickup roller takes out the paper from the paper storage section and supplies it to the transport roller and the reverse port. This pickup roller is rotatably attached to the tip of the pickup arm. The pick amp arm fits into the rotation groove and is rotatable.

When feeding paper, the pickup arm is rotated by the rotation mechanism, and the pickup roller is brought into contact with the paper in the paper storage section. Then, rotate the pickup roller,
The paper is sent out. The paper that has been sent out is held between a conveyance roller and a reverse roller, and is sent out further forward. After the paper is supplied, the pick amplifier arm is rotated to retract the pickup roller above the paper storage section.

Here, if multiple sheets of paper are sent out at once by the pink up roller, one of them on the conveyance roller side
Only one sheet of paper is sent forward by a conveyance roller, and the remaining sheets are sent back to the paper storage section by a reverse throw. At this time, since the pickup roller is already in the retracted position, the paper is smoothly fed back by the reverse roller. This makes it possible to reliably separate the multi-fed sheets when the sheets are multi-fed during paper supply.

[Problem to be solved by the invention]

The conventional configuration requires a pickup arm and its rotation mechanism, resulting in a complicated structure. Furthermore, since the pickup roller and the pickup arm have relatively large inertia, they may not be able to sufficiently follow the copying speed of a high-speed image processing apparatus.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet feeding device that can reliably separate double-fed sheets with a simple mechanism and that can fully meet high-speed specifications.

[Means to solve the problem]

A paper feeding device according to the present invention is a paper feeding device of a paper feeding device that has a conveyance roller and a reverse roller and supplies paper from a paper storage section to a paper receiving section while preventing double feeding of paper. be. This paper feeding device includes a pickup member capable of rotating 1 iJ and a drive control means.

) The pick-up member 111 has a protruding paper abutting part made of an elastic member, and is used to take out the paper from the paper storage section and feed the paper to the transport roller and reverse roller side. The drive control means is a means for driving and controlling the pickup member so that it rotates when paper is fed out, and the paper contacting portion is in a retracted position away from the paper in the paper storage unit when paper is not fed out.

[Effect]

In the paper feeding device according to the present invention, the pickup member is rotated by the drive control means when feeding the paper. Then, the paper contacting portion of the pickup member comes into contact with the paper in the paper storage unit and is elastically deformed.

When the pickup member further rotates from this state, the repulsive force and frictional force of the elastically deformed portion removes the paper from the paper storage section, and the paper is sent toward the transport roller and reverse roller. Then, the paper is supplied to the paper receiving section by the conveyance roller and the reverse roller.

After the paper is sent out, the paper contacting portion of the pickup member assumes a retracted position away from the paper in the paper storage section under the control of the drive control means.

If the sheets are fed in duplicate when the sheets are sent out, the reverse roller rotates in the opposite direction, and the duplicated sheets are about to be returned to the paper storage section. At this time, the paper contacting portion of the pickup member is separated from the paper in the paper storage section. Therefore, the double-fed sheets can smoothly return to the sheet storage section.

In this way, double-fed sheets can be reliably separated using a simple mechanism. Further, since the inertia of the pickup member can be reduced, it is possible to sufficiently correspond to high-speed specifications.

〔Example〕

FIG. 2 shows the overall configuration of a copying machine employing an embodiment of the present invention.

The copying machine main body 1 is composed of an upper main body 1a and a lower main body 1b, and the upper main body 1a can be opened and closed around a hinge portion 18.

A document table 2 is fixed to the top surface of the copying machine main body l.
A document presser 3 is attached to the upper part of the document table 2 so as to be openable and closable. A paper feed cassette 4 is removably attached to the right side of the copying machine main body 1. Further, on the left side, there is installed a paper discharge tray 6 from which copied sheets are discharged.

Inside the copying machine main body 1, an optical system 7 for reading image information of a document is provided on the upper side la of the main body. The optical system 7 includes a light source, a mirror lens, and the like. Further, a photosensitive drum 8 on which an electrostatic latent image is formed on the surface of the photosensitive drum 8 is arranged at the center inside the lower part 1b of the main body. Around the photoreceptor drum 8, there are a charging device 9 that charges the photoreceptor drum 8 to a predetermined charge, a developing device 101 that develops an electrostatic latent image, a transfer device 11 that transfers a toner image onto a sheet of paper, and a photoreceptor. A paper separation device ff12 for separating paper from the drum 8 and a cleaning device 13 for removing toner from the photosensitive drum 8 are arranged in this order. A paper feed conveyance path 14 for conveying paper is provided between the paper feed cassette 4 and an image forming section constituted by the photosensitive drum 8 and the like.

Further, a paper discharge transport path 15 is provided downstream of the image forming section in the paper transport direction. A fixing device 16 for fixing the transferred image on the transported paper and a paper ejection roller 17 are provided between the paper ejection transport path 15 and the paper ejection tray 6.

Between the paper feed cassette 4 and the paper feed conveyance path 14, a conveyance roller 30 for conveying the paper in the paper feed cassette 4 to the paper feed conveyance path 14 side, and a paper weight roller 30 disposed opposite to the conveyance roller 30 are provided. A reverse roller 31 is provided to prevent feeding. Further, a rotatable pickup member 20 is provided above the front end (left end in the drawing) of the paper feed cassette 4 for feeding out the paper from the paper feed cassette 4 to the transport roller 30 and reverse roller 31 side.

As shown in FIG. 1, the pickup member 20 has a horizontal shaft 21 provided above the paper feed cassette 4 at a predetermined interval.
and a flat sheet contacting portion 22 provided on the outer periphery of the horizontal shaft 21 on substantially the same plane. The horizontal axis 21 is
It is designed to be rotated in the direction of the arrow by a drive motor (not shown). The pair of paper contact portions 22 are made of an elastic member (for example, silicone rubber) having a high coefficient of friction.

Further, the conveyance roller 30 is configured to be rotationally driven in the direction of the arrow by a drive motor (not shown) via a clutch mechanism (not shown). The reverse roller 31 is attached to a shaft 32 parallel to the rotation axis of the conveyance roller 30.

This shaft 32 is rotatable in the direction of the arrow and can be moved up and down a certain amount. An arm 33 is in contact with the shaft 32 from below. The arm 33 is rotatable around a fulcrum 37, and a coil spring 34 is attached to its lower end. Due to the spring force of this coil spring 34, the arm 33 rotates around a fulcrum 37 and pushes up the shaft 32. Thereby, the reverse roller 31 can contact the conveyance roller 30 with a predetermined pressure. Further, the shaft 32 of the reverse roller 31 has a third
A torque limiter 40 as shown in the figure is provided.

In FIG. 3, the clockwise arrow direction corresponds to the direction of rotation of the shaft 32. The reverse roller 31 is the roller part 3
1a, and a protrusion 31b formed at one end thereof. A limiter spring 41 is fitted into this protrusion 31b. The limiter spring 41 is made of a wire rod twisted in the direction shown in the drawing. A limiter boss 42 is engaged with the limiter spring 41 from the side. This limiter boss 42 has a boss portion 44 that fits into the limiter spring 41.
and a pin 45 that can be engaged with one end 41a of the wire rod of the limiter spring 41. The limiter spring 41 is housed within the limiter collar 43.

Further, this copying machine has a control section 50 as shown in FIG. The control unit 50 includes a microcomputer including a CPU, ROM, RAM, and the like. The control section 50 is connected to a keyboard 51 disposed on the front side of the upper end surface of the main body upper part 1a (FIG. 2) and other input sections.

Also connected to the control section 50 are a drive motor 52 for the transport roller and reverse roller, a drive motor 53 for the pickup member, and other output sections.

Next, the operation of the above embodiment will be described with reference to FIGS. 5A and 5B showing control operations by the control section 50.

When the main switch (not shown) is turned on, initial settings such as setting the number of copies to 1 are performed in step S1 of FIG. 5A.Next, in step S2, it is determined whether or not the print key has been pressed. do. If the print key is not pressed, the process moves to step S3. In step S3, a subroutine corresponding to the other person's key is executed, and when the process is completed, the process returns to step S2.

If the print key is pressed here, the program moves from step S2 to step S4 in FIG. 5B.

In step S4, the drive motor 52 of the conveyance roller 30 and reverse roller 31 is driven, and the conveyance roller 30 and shaft 32 begin to rotate in the direction of the arrow in FIG. The rotation of the shaft 32 causes the limiter boss 42 fixed to the shaft 32 to rotate in the direction of the arrow in FIG. Then, the pin 45 of the limiter boss 42 presses one end 41a of the wire of the limiter spring 41 in the direction of expanding the diameter. On the other hand, as described above, the roller surface of the reverse roller 31 is in pressure contact with the roller surface of the conveyance roller 30, and a large load is applied to the reverse roller 31 in the direction opposite to the rotational direction of the hinge boss 42.

Therefore, the torque limiter 40 slips, and the reverse roller 31 rotates following the conveyance roller 30 regardless of the rotation of the limiter boss 42.

Next, the process moves to step S5. In step S5, the drive motor 53 is driven to rotate the pick amplifier member 20. Note that the drive time of the drive motor 53 is preset to the time required for the paper taken out from the paper storage section 4 to be sent between the nip between the conveyance roller 30 and the reverse roller 31. The rotation of the pickup member 20 causes the pickup member 2 to rotate as shown in FIG. 6A.
The paper contact portion 22 of No. 0 contacts the paper 35 of the paper feed cassette 4 and is elastically deformed. When the pickup member 20 is further rotated from this state, the paper is sent forward (to the left in the figure) due to the repulsive force and frictional force of this elastically deformed portion.

The fed paper 35 is fed between the nip between the rotating conveyor [1-ra 30 and reverse roller 31]. At this time, if only one sheet of paper 35 is fed, the transport roller 30 transfers the paper 35 to the reverse roller 3.
I is held in a driven rotation state. As a result, the paper 35 is conveyed toward the paper feed conveyance path 14 (FIG. 2) through the nip. When the process in step S5 is finished, step S6
to move to. In step S6, as shown in FIG. 6B, the pickup member 20 is stopped in a retracted position substantially parallel to the paper 35. In this way, the paper feeding operation is completed.

Next, a case will be described in which sheets are fed multiple times during sheet feeding as shown in FIG. 6A. As shown in FIG. 6B, the paper 35
When the paper 36 that is double-fed is sent between the nip between the transport roller 30 and the reverse roller 31, the paper 3
Since the friction coefficient between 5 and 36 is relatively small, it becomes difficult for the reverse roller 31 to follow the conveyance roller 30, and the torque limiter 40 is engaged. That is, reverse roller 3
1 is driven by a limiter boss 42 via a limiter spring 41 (FIG. 3). As a result, the reverse roller 31 rotates in the direction of the arrow in FIG. 6B (clockwise), and the double-fed sheets 36 are returned to the sheet feeding cassette 4 side. At this time, as described above, the pickup member 20 is placed in the retracted position away from the paper 35. Therefore, the pickup member 20 does not get in the way of the paper 36 when the paper 36 that has been multi-fed is returned.

In this way, by using a simple mechanism, the double fed paper 3
6 can be easily separated from the paper 35. Also,
Since the inertia of the pickup member 20 is relatively small, even when the copying speed is high, it can sufficiently follow the copying speed.

When the process in step S6 is completed, the process moves to step S7. In step S7, development and transfer are performed.

The remaining copying operations such as fixing and fixing are then performed. When all copying operations are completed, the process returns to the main routine of FIG. 5A.

[Other Examples]

(a) In the embodiment described above, the pickup member 20 has two paper contact portions 22, but the application of the present invention is not limited to this.

For example, it may have three or more paper contact parts 22, and the paper contact parts 22 are not limited to those having a rectangular cross section, but may have, for example, a semicircular cross section. You can.

The torque limiter attached to the reverse roller 31 does not have to be of a coil spring type, but may be of a so-called powder type using magnetic powder as a medium, for example.

[Effects of the Invention] According to the paper feeding device according to the present invention, since the pickup member having the paper contacting portion is placed in a retracted position away from the paper in the paper storage unit when the paper is not delivered, double-fed paper can be removed. Separation can be reliably performed with a simple mechanism. Moreover, it can fully correspond to high-speed specifications.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a paper feeding device employing a paper feeding device according to an embodiment of the present invention, FIG. 2 is a schematic vertical cross-sectional view of a copying machine employing an embodiment of the present invention, and FIG. 1 is a perspective exploded view showing the internal structure of the torque limiter, FIG. 4 is a button configuration diagram of the control section, and FIGS. 5A and 5!
The chart, FIG. 6, and FIG. 611 are diagrams for explaining the operation of the 11:1 embodiment. 4...Paper feed cassette, 20...Pickup member,
22...Paper contact portion, 30...Transporting 1-ra, 31
... Reverse roller, 50... Control section.

Claims (1)

[Claims] (1) A paper feeding device of a paper feeding device, which has a conveyance roller and a reverse roller, and is configured to supply paper from a paper storage section to a paper feeding section while preventing double feeding of paper, from an elastic member. a rotatable pickup member having a protruding paper abutting part for taking out the paper from the paper storage section and sending the paper to the transport roller and the reverse roller side; so that the paper contacting section is in a retracted position away from the paper in the paper storage section,
A paper feeding device for a paper feeding device, comprising: drive control means for controlling drive of the pickup member.