JP2009234771A - Paper feeder and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder and an image forming apparatus capable of performing effective cleaning for various paper, by performing the cleaning such as a pickup roller even in paper feeding operation. <P>SOLUTION: The paper feeder has the pickup roller 42, a paper feeding roller 44, a separation roller 18 and a cleaning roller 45. In the cleaning roller 45, roller parts 45a and 45b are juxtaposed on a rotary shaft 60. The cleaning roller 45 contacts with the separation roller 18, and rotates by being driven by rotation of the separation roller 18 by frictional force with the separation roller 18. The cleaning roller 45 can move in parallel to the arrow X direction (in the axial direction of the pickup roller 42, the paper feeding roller 44 and the separation roller 18). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a paper feeding device such as a copying machine, a facsimile machine, and a printer, and an image forming apparatus.

  In general, a paper feeding device such as a copying machine or a printer has a pickup roller that feeds a stack of sheets stacked in a cassette into a main body, and a paper feed that is rotationally driven in the transport direction to separate and transport the sheets one by one. A roller and a separation roller for separating the paper are provided. Each of these rollers conveys the sheet using friction generated between the rollers. However, when paper dust or the like of the paper adheres to the roller surface, the friction resistance between the paper and the roller decreases, and the roller may not be able to carry the paper.

  As a measure for preventing such problems, Patent Document 1 discloses that paper powder or the like adhered to the surface of the separation roller by rotating the separation roller after temporarily separating the separation roller from the paper feed roller. A technique for removing by a cleaning member is described. Patent Document 2 describes a technique for removing paper dust adhering to the surfaces of a paper feed roller and a separation roller by bringing a cleaning member into contact with the paper feed roller and the separation roller.

JP 7-215510 A Japanese Patent Laid-Open No. 3-128732

  However, the conventional paper feeding device using the above technology needs to be cleaned as needed when paper with a lot of paper dust is passed through, and paper dust removal is not in time if the paper is regularly cleaned. Furthermore, the technique of Patent Document 1 has a problem that the paper feeding operation must be interrupted during cleaning. Further, even though it is paper dust, paper dust having various characteristics is generated depending on the type of paper, and there is a limit to removing it with a certain cleaning means.

  SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a paper feeding device and an image forming apparatus that can clean a pickup roller and the like even during a paper feeding operation and can perform effective cleaning on various papers. That is.

  The invention according to claim 1 is a paper feed device that separates the uppermost paper from the paper stacked in the paper feed cassette and transports the paper in the paper transport direction, the pickup roller for guiding the paper to the paper separator, A paper feed roller and a separation roller for paper feed separation, and a cleaning member for contacting the at least one of the pickup roller, the paper feed roller, and the separation roller to remove deposits on the roller. The sheet feeding device is characterized in that the member is movable in parallel with respect to the axial direction of the pickup roller, the sheet feeding roller, and the separation roller.

  According to the first aspect of the present invention, since the cleaning member that is movable in parallel with respect to the axial direction of the pickup roller, the sheet feeding roller, and the separation roller is provided, the cleaning member is moved in parallel during the sheet feeding operation, so that the pickup roller, etc. The point of contact with can be shifted. As a result, the portion of the cleaning member from which the paper dust adhering to the surface of the pickup roller or the like has been removed is separated from the pickup roller or the like. In place of this, the portion that has not been in contact so far comes into contact with the pickup roller or the like, and the paper dust adhering to the surface of the pickup roller or the like is removed without interrupting the paper feeding operation. On the other hand, at the portion of the cleaning member that has been in contact with the pickup roller so far, the paper dust and the like attached thereto is removed using a cleaning blade or the like during the paper feeding operation, and the cleaning member surface is cleaned.

  The invention according to claim 2 is an invention dependent on the invention according to claim 1, wherein the cleaning member is a roller in which a plurality of roller portions made of different materials are coaxially arranged side by side. It is a paper device.

  For example, paper dust has various characteristics depending on the type of paper. Therefore, according to the second aspect of the present invention, by using a cleaning roller in which a plurality of roller portions made of different materials are coaxially arranged, the roller portions are switched in accordance with the type of paper. That is, paper dust and the like are efficiently removed by moving the cleaning roller in parallel and switching to a material of a roller portion suitable for paper dust having various characteristics depending on the type of paper.

  The invention according to claim 3 is an invention dependent on the invention according to claim 1, characterized in that the cleaning member is a roller in which a plurality of roller portions charged at different potentials are coaxially arranged side by side. This is a paper feeding device.

  Depending on the type of paper, the configuration of the apparatus, and the like, paper dust may be charged to a positive potential or charged to a negative potential. Therefore, in the invention of claim 3, by using a cleaning roller in which a plurality of roller portions charged at different potentials are arranged in parallel, the roller portions are switched in accordance with the charged potential of the paper dust. That is, by moving the cleaning roller in parallel and switching to a roller portion having a charging potential opposite to the charging potential of the paper dust, the paper dust is attracted to the cleaning roller to efficiently remove the paper dust.

  The invention according to claim 4 is an invention dependent on the invention according to any one of claims 1 to 3, comprising a cleaning blade for contacting the cleaning member and removing deposits on the cleaning member. A sheet feeding device.

  In the invention of claim 4, since the cleaning blade is provided, the deposit on the cleaning member can be reliably removed by the cleaning blade.

  According to a fifth aspect of the present invention, there is provided an image forming apparatus comprising the paper feeding device according to any one of the first to fourth aspects.

  According to the fifth aspect of the present invention, the pickup roller and the like are cleaned even during the paper feeding operation by providing a cleaning member that can move in parallel with the axial direction of the pickup roller, paper feed roller, and separation roller. It becomes possible to carry out effective cleaning for a simple sheet. Therefore, a small sheet feeding device having a simple configuration and low manufacturing cost is obtained.

  According to the present invention, by providing a cleaning member that can move in parallel with the axial direction of the pickup roller, the paper feed roller, and the separation roller, the pickup roller and the like are cleaned even during the paper feeding operation, A paper feeding device and an image forming apparatus capable of performing effective cleaning on the paper are obtained.

  The above-described object, other objects, features, and advantages of the present invention will become more apparent from the following description of the best mode for carrying out the invention with reference to the drawings.

(Image forming device)
FIG. 1 is a schematic configuration diagram showing an image forming apparatus 1 including a paper feeding device according to the present invention.

  The photosensitive drum 24 disposed in the central portion of the image forming apparatus 1 is driven at a predetermined speed in a clockwise direction indicated by an arrow in the figure by a driving unit. In the vicinity of the outer periphery of the photosensitive drum 24, a charger 32, a developing unit 22, a transfer roller 23, and a rubbing member 30 are provided. The surface of the photosensitive drum 24 is charged by a charger 32. A laser scanning unit 26 is disposed on the downstream side of the charger 32 in the rotation direction of the photosensitive drum 24. The laser beam L emitted from the laser scanning unit 26 is irradiated onto the photosensitive drum 24 through the reflection mirror 28 to form an electrostatic latent image.

  On the upstream side of the laser scanning unit 26, a developing device 22 is disposed. The developing device 22 is for applying black toner to the photosensitive drum 24. A toner cartridge 20 is disposed with respect to the developing device 22.

  A transfer roller 23 is disposed on the downstream side of the developing device 22. Further, a rubbing member 30 for removing the toner remaining on the photosensitive drum 24 is disposed on the downstream side of the transfer roller 23.

  On the other hand, the pickup roller 42 pulls out the paper P as a recording material from the paper feed cassette 2 in synchronization with the black toner image, and feeds it through the separation roller 18 and the paper feed roller 44. The toner image formed on the photosensitive drum 24 is transferred to the paper P and is carried into the fixing device 46. The paper P to which the toner image has been transferred is fixed by the fixing device 46, discharged as a printed matter outside the apparatus, and stacked on the paper discharge tray 50.

(First paper feeder)
Next, the first paper feeding device will be described with reference to FIGS. 2 is a schematic configuration diagram of each roller of the sheet feeding device, FIG. 3 is a schematic configuration diagram of a parallel movement mechanism of a cleaning roller (cleaning member), and FIG. 4 is a schematic configuration for explaining the operation of the cleaning roller. FIG.

  The paper feed cassette 2 of the paper feed device has a box shape with four walls surrounded by walls, and the paper P is accommodated therein. A pickup roller 42, a paper feed roller 44, a separation roller 18, and a cleaning roller 45 are provided above the top side in the paper transport direction of the paper feed device. The pickup roller 42 and the paper feed roller 44 can be driven to rotate in the paper transport direction by a motor mounted in the image forming apparatus main body. The separation roller 18 is in contact with the paper feed roller 44 by the elastic force of a coil spring (not shown), and since the frictional force with the paper feed roller 44 is greater than the braking force of the braking means, the paper feed roller. It rotates following the rotational drive of 44.

  The cleaning roller 45 has roller portions 45a and 45b arranged in parallel with an interval in the axial direction of the rotary shaft 60. The cleaning roller 45 is in contact with the separation roller 18 and rotates following the rotation of the separation roller 18 by the frictional force with the separation roller 18. The cleaning roller 45 is movable in the direction of the arrow X (in the axial direction of the pickup roller 42, the paper feed roller 44, and the separation roller 18). That is, as shown in FIG. 3, the drive motor 62 causes the worm gear 64 to rotate clockwise or counterclockwise. This rotational force is transmitted to the worm gear 68 via the idle gear 66. Since the worm gear 68 receives a force in a direction in which the idle gear 66 tries to rotate, the rotation shaft 60 of the cleaning roller 45 connected to the worm gear 68 translates in the direction of the arrow X. The number of roller portions is not necessarily limited to two, and the number is arbitrary.

Next, the operation of this paper feeder will be described.
When the paper feed cassette 2 is mounted on the image forming apparatus 1, the uppermost part of the paper P stacked in the paper feed cassette 2 comes into contact with the pickup roller 42. When the main body of the image forming apparatus receives a paper feed command, the motor of the main body of the image forming apparatus is driven, and the driving force is transmitted to the pickup roller 42, the paper feed roller 44, the separation motor 18 and the cleaning roller 45. , 18, 45 are rotationally driven.

  Thereafter, the pick-up roller 42, the paper feed roller 44, and the separation motor 18 separate the uppermost paper P from the paper P stacked in the paper feed cassette 2 and transport it in the paper transport direction. Paper dust or the like adhering to the surface of the separation roller 18 as the paper P is conveyed is removed by the roller portion 45 a of the cleaning roller 45 that is in contact with the separation roller 18.

  When the paper feeding operation elapses for a predetermined time, the motor 62 is driven to move the cleaning roller 45 in parallel as shown in FIG. 4, and the roller portion 45a that contacts the separation roller 18 is switched to the roller portion 45b. That is, the roller portion 45 a that has removed the paper dust adhering to the surface of the separation roller 18 is separated from the separation roller 18. Instead, the roller portion 45b that has not been in contact with the roller contacts the separation roller 18 and removes the paper dust adhering to the surface of the separation roller 18 without interrupting the paper feeding operation. On the other hand, the roller portion 45a that has been in contact with the separation roller 18 until now is freed of paper dust and the like adhering to the surface by using a cleaning blade or the like (not shown) during the paper feeding operation. The surface is cleaned.

  In this way, the image forming apparatus 1 including the paper feeding device that can perform the cleaning of the separation roller 18 even during the paper feeding operation only by providing the cleaning roller 45 that is movable in parallel with the axial direction of the separation roller 18. Is obtained.

(Second paper feeder)
Next, the second paper feeding device will be described with reference to FIG. FIG. 5 is a schematic configuration diagram of each roller of the second sheet feeding device. The same parts and portions as those of the first paper feeding device are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the second paper feeding device, the roller unit 45a and the roller unit 45b are made of different materials. For example, paper dust has various characteristics depending on the type of paper. Therefore, in the second paper feeding device, the two roller parts 45a and 45b of different materials (differing in hardness, wear degree, etc.) are used as the cleaning roller 45 arranged in parallel and spaced apart from each other. The roller part 45a and the roller part 45b are switched correspondingly. That is, paper dust and the like can be efficiently removed by moving the cleaning roller 45 in parallel and switching to roller portions 45 and 45b suitable for paper dust having various characteristics depending on the type of paper.

  Alternatively, the roller unit 45a and the roller unit 45b are switched corresponding to the destination (cold region, extreme heat region, wet region, etc.). That is, paper dust and the like can be efficiently removed by moving the cleaning roller 45 in parallel and switching to the roller portions 45 and 45b suitable for the environment of the destination.

  Further, paper dust may be charged to a positive potential or charged to a negative potential depending on the type of paper, the configuration of the apparatus, and the like. Accordingly, the two roller portions 45a and 45b charged at different potentials are used as the cleaning roller 45 that is coaxially arranged in parallel, so that the roller portion 45a and the roller portion 45b are switched in accordance with the charged potential of the paper dust. That is, by moving the cleaning roller 45 in parallel and switching to a roller portion 45a (or roller portion 45b) having a charging potential opposite to the charging potential of the paper dust, the paper dust is attracted to the cleaning roller 45 and the paper dust or the like Removal can be performed efficiently. For example, when nylon resin is used as the material for the roller portion, the roller portion is charged to a positive potential. Further, when a polyester resin is used as the material for the roller portion, the roller portion is charged to a negative potential.

  Further, the paper feeding device includes a cleaning blade 70 that contacts the cleaning roller 45 and removes deposits on the cleaning roller 45. Therefore, even during the paper feeding operation, paper dust or the like on the surfaces of the roller portions 45 a and 45 b of the cleaning roller 45 can be reliably removed by the cleaning blade 70.

  The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the gist. For example, the cleaning member may be a brush or the like in addition to the roller. In the present embodiment, the cleaning roller 45 that is in contact with the separation roller 18 to which paper dust or the like is most likely to adhere is described as a representative example, but the present invention is not limited to this. Even if the cleaning roller 45 is in contact with the pickup roller 42 or the paper feed roller 44, the same effect can be obtained.

1 is a schematic configuration diagram illustrating an image forming apparatus according to the present invention. It is a schematic block diagram of each roller of the 1st paper feeder which concerns on this invention. It is a schematic block diagram of the parallel displacement mechanism of a cleaning roller. It is a schematic block diagram for demonstrating operation | movement of a cleaning roller. It is a schematic block diagram which shows the 2nd sheet feeding apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Paper feed cassette 18 Separation roller 42 Pickup roller 44 Paper feed roller 45 Cleaning roller 45a, 45b Roller part 70 Cleaning blade

Claims (5)

A paper feeding device that separates the top paper from the paper stacked in a paper feeding cassette and transports it in the paper transport direction,
A pick-up roller for guiding to the paper separating section;
A paper feed roller and a separation roller for feeding and separating paper;
A cleaning member that contacts at least one of the pickup roller, the paper feed roller, and the separation roller to remove deposits on the roller, and
The sheet feeding device, wherein the cleaning member is movable in parallel with respect to an axial direction of the pickup roller, the sheet feeding roller, and the separation roller.   The sheet feeding device according to claim 1, wherein the cleaning member is a roller in which a plurality of roller portions made of different materials are coaxially arranged.   The sheet feeding device according to claim 1, wherein the cleaning member is a roller in which a plurality of roller portions charged at different potentials are coaxially arranged.   The sheet feeding device according to claim 1, further comprising a cleaning blade that contacts the cleaning member to remove deposits on the cleaning member.   An image forming apparatus comprising the paper feeding device according to claim 1.

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