JP2011235979A - Paper carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper carrying device suppressing the noise generated when a carried paper bumps against or rubs a guide member as much as possible.SOLUTION: The paper carrying device includes: the guide member 40 configuring a paper carrying passage 33; retaining members 50 retaining the guide member 40; and elastic members 60 interposed between the guide member 40 and the retaining members 50. The guide member 40 is disposed at the position where the carried paper bumps and latched onto the retaining members 50, in a state biased by the elastic force of the elastic members 60 toward the inside of the paper carrying passage 33, and by coming off stoppers 41.

Description

  The present invention relates to a sheet conveying apparatus, and more particularly to a sheet conveying apparatus in an electrophotographic image forming apparatus such as a copying machine or a printer.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus such as a copying machine or a printer, noise is generated when a sheet collides with or rubs against a guide member constituting a conveyance path when the sheet is conveyed by a pair of conveyance rollers. There is a problem. Further, when the sheet passes through the pair of conveyance rollers, the rear end portion of the sheet hits the guide member by a reaction force that returns from the bent state to the original, which causes noise.

  In order to eliminate such noise caused by the conveyance of the paper, in Patent Document 1, an elastic member such as a film is disposed on the downstream side in the conveyance direction of the guide member, and the trailing edge of the paper is utilized by utilizing the bending of the elastic member. It is described that the noise caused by the collision is reduced. In recent years, with the speed of printing processing, the conveyance of paper has been accelerated, the demand for quietness of the apparatus is high, and the reduction of noise associated with the conveyance of paper that can occur in various states is required.

JP 2006-69768 A

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a paper transport apparatus that can suppress as much as possible the noise that occurs when the transported paper collides with a guide member or rubs.

In order to achieve the above object, a paper conveying apparatus according to an aspect of the present invention is provided.
A guide member constituting a paper transport path;
A holding member for holding the guide member;
An elastic member interposed between the guide member and the holding member;
With
The guide member having the elastic member interposed between the holding member and the holding member is disposed at a position where the conveyed paper collides;
It is characterized by.

  In the paper transport device, when the leading end or the rear end of the transported paper collides with or rubs against the guide member, the guide member is held by the holding member via the elastic member. The force is absorbed by the elastic member, and the generation of noise is suppressed.

  According to the present invention, it is possible to suppress as much as possible noise when the conveyed paper collides with or slides on the guide member.

1 is a schematic configuration diagram illustrating an image forming apparatus provided with a sheet conveying device according to the present invention. 1 shows a sheet conveying apparatus according to a first embodiment, in which (A) is a schematic sectional view in a vertical direction, and (B) is an XX sectional view of (A). FIG. 6 is a schematic elevation view illustrating a sheet conveying apparatus according to a second embodiment. It is a top view which shows the principal part of the paper conveying apparatus which is 3rd Example. It is a perspective view which shows the principal part of the paper conveying apparatus which is the said 3rd Example. It is sectional drawing which shows the principal part of the paper conveying apparatus which is 4th Example. It is a perspective view which shows the principal part of the paper conveying apparatus which is the said 4th Example.

  Hereinafter, embodiments of a sheet conveying device according to the present invention will be described with reference to the accompanying drawings. In addition, in each figure, the code | symbol which shows the same member and part is used in common. Each drawing showing the embodiment is schematically drawn for convenience of explanation, and the thickness of the member does not follow the actual dimensional ratio.

(Schematic configuration of image forming apparatus, see FIG. 1)
First, a schematic configuration of an image forming apparatus provided with a sheet conveying device according to the present invention will be described with reference to FIG. This image forming apparatus is an electrophotographic color printer and is configured to form an image of four colors (Y: yellow, M: magenta, C: cyan, K: black) by a so-called tandem method. is there. An image is formed at each image forming station 101 and is combined on the intermediate transfer belt 112. In FIG. 1, the letters Y, M, C, and K attached to the reference numerals mean members for yellow, magenta, cyan, and black, respectively.

  The outline of each image forming station 101 will be described. A laser scanning optical device 110 is arranged including a photosensitive drum 102, a developing device 103, and the like. A light beam emitted from the laser scanning optical device 110 irradiates each photosensitive drum 102 to form an image of each color. On the other hand, an intermediate transfer belt 112 is stretched endlessly immediately above the image forming station 101 and is installed so as to be rotatable in the direction of arrow A. In addition, in the lower stage of the image forming apparatus, automatic paper feeders 130 that feed stacked sheets one by one are installed in three stages.

  The image data is input to an image processing unit (not shown) as image data for each YMCK from an image reading device (scanner) 125 provided with the automatic document feeder 120 or a computer, and based on the driving image data generated there. The laser scanning optical device 110 is driven to form an electrostatic latent image on each photosensitive drum 102 and then developed. Such an electrophotographic process is well known and will not be described.

  The toner images formed on the respective photosensitive drums 102 are sequentially primary-transferred onto an intermediate transfer belt 112 that is rotationally driven in the direction of arrow A by an electric field applied from a primary transfer charger (not shown), and four color images are formed. Images are synthesized. On the other hand, the sheets are fed one by one from one of the sheet feeding sections 130, and the composite image is secondarily transferred from the intermediate transfer belt 112 by the electric field applied from the secondary transfer roller 113. Thereafter, the sheet is conveyed to the fixing device 115 where the toner is heated and fixed, and is discharged from the discharge roller pair 116 to the tray unit 140.

  A paper feed roller 31 and a separation roller 32 are disposed in the paper feed unit 130, respectively, and one sheet picked up by the rollers 31 and 32 is sent to the transport path 33. The fed paper is transported upward by the transport roller pair 34 along the transport path 35 arranged in the vertical direction, transported further upward by the transport roller pair 36, and sent to the secondary transfer section. Hereinafter, the configuration of the transport path 33 will be described as an example. Here, for convenience, the rollers 31 and 32 are referred to as an upstream roller pair, and the transport roller pair 34 is referred to as a downstream roller pair.

(See the first embodiment, FIG. 2)
As shown in FIGS. 2A and 2B, the sheet conveying apparatus according to the first embodiment is configured such that the guide member 40 is attached to the holding member 50 via the elastic member 60 in the vertical direction along the conveying path 33. Is. The elastic member 60 is made of rubber, foam material, or the like, and is adhered to the guide member 40 or the holding member 50. The attachment positions of the elastic member 60 are the four corner portions of the guide member 40. Alternatively, the elastic member 60 may be attached to the upper and lower end portions of the guide member 40 and the full width portion orthogonal to the transport direction of the paper S.

  Further, the retaining portion 41 projecting from the guide member 40 passes through the hole 52 of the projecting piece 51 of the holding member 50, and the elastic member 60 is sandwiched between the guide member 40 and the projecting piece 51. Thus, the guide member 40 is locked to the holding member 50 at the position shown in FIG.

  In the above configuration, the leading edge of the sheet S sent from the upstream roller pair 31 and 32 to the conveyance path 33 collides with a substantially intermediate position in the height direction of the guide member 40. When the guide member 40 is fixed, a collision sound due to the leading edge of the paper S is generated. However, in the first embodiment, the guide member 40 is slightly retracted in the direction of the arrow B by the elasticity of the elastic member 60 due to the collision of the paper S, and the impact force and vibration are absorbed by the elastic member 60, though not all of them. As a result, noise (such as collision noise and rubbing noise) is suppressed.

  In this type of transport device, the transport speed (rotational speed) of the downstream roller pair 34 is set slower than the transport speed (rotational speed) of the upstream roller pairs 31 and 32. This is to prevent the downstream roller pair 34 from pulling the paper S. Therefore, the sheet S is bent as shown by S ′ in FIG. In this state, when the trailing edge of the sheet S is separated from the upstream roller pair 31, 32, the trailing edge (flexible portion S ′) of the sheet S is repelled and strikes the guide member 40. The impact at this time is also absorbed by the elastic member 60, and noise is suppressed.

(Refer to the second embodiment, FIG. 3)
As shown in FIG. 3, the sheet conveying apparatus according to the second embodiment is configured such that a support shaft 42 provided on a guide member 40 is rotatably attached to a holding member, and the guide member 40 swings around the support shaft 42 as a fulcrum. Is possible. An elastic member 60 is attached to the upper and lower portions of the guide member 40, and the elastic member 60 is sandwiched between the protruding piece 53 of the holding member and the guide member 40. The support shaft 42 is disposed in the vicinity of the position where the leading edge of the sheet S sent to the transport path 33 from the upstream roller pair 31 and 32 collides.

  In the above configuration, the guide member 40 slightly swings in the direction of the arrow C (or the direction opposite to the arrow C) with the support shaft 42 as a fulcrum by the elasticity of the elastic member 60 when the conveyed paper S collides or rubs. The impact force and vibration are absorbed by the elastic member 60, but not all of them, and noise (such as collision noise and rubbing noise) is suppressed. In particular, in the second embodiment, the support shaft 42 is disposed in the vicinity of the position where the leading edge of the paper S sent to the transport path 33 collides, and therefore the guide member 40 is not shaken due to the collision of the leading edge of the paper S. Thus, the sheet S can be guided in a stable state. The elastic member 60 and the protruding piece 53 provided below the guide member 40 are arranged on both sides of the transport path 33 and out of the transport area of the paper S, and do not interfere with the transported paper S. Absent.

(Refer to the third embodiment, FIGS. 4 and 5)
The sheet conveying apparatus according to the third embodiment basically has the same configuration as that of the first embodiment, and as shown in FIGS. 4 and 5, restricting portions 54 and 55 that restrict the movement of the guide member 40. Is provided on the holding member 50. That is, the guide member 40 and the elastic member 60 are sandwiched at the offset positions by the restricting portions 54 and 55 protruding from the holding member 50, and the movement of the guide member 40 for suppressing noise due to elastic deformation of the elastic member 60 is restricted. I have to.

(Refer to the fourth embodiment, FIGS. 6 and 7)
In the paper conveying apparatus according to the fourth embodiment, the guide member 40 is positioned and fixed to the holding member 50 via the elastic member 60. That is, as shown in FIGS. 6 and 7, an elastic member 60 is interposed between the protruding piece 43 of the guide member 40 and the holding member 50, and a screw 56 is screwed to the protruding piece 43 from the holding member 50 side. Yes.

  In the above configuration, when the paper collides and rubs against the guide member 40, the impact force and vibration are absorbed by the elastic member 60, but not all of them, and noise (such as collision sound and rubbing sound) is suppressed.

(Other examples)
The paper conveying device according to the present invention is not limited to the above embodiment, and can be variously modified within the range of the paper.

  For example, in addition to being arranged in the paper feeding unit, the paper conveying device may be a paper conveying unit in another part of the image forming apparatus, or a paper conveying unit of a finisher device that performs stapling or folding processing. .

  As described above, the present invention is useful for a sheet conveying apparatus, and is particularly excellent in that noise when a conveyed sheet collides with a guide member or is rubbed can be suppressed as much as possible.

31, 32 ... Upstream roller pair 33 ... Conveying path 34 ... Downstream roller pair 40 ... Guide member 41 ... Retaining part 42 ... Support shaft 50 ... Holding member 54,55 ... Regulator 56 ... Screw

Claims (5)

A guide member constituting a paper transport path;
A holding member for holding the guide member;
An elastic member interposed between the guide member and the holding member;
With
The guide member having the elastic member interposed between the holding member and the holding member is disposed at a position where the conveyed paper collides;
A paper conveying device characterized by the above. The guide member is biased to the inside of the paper transport path by the elastic force of the elastic member and is locked to the holding member by a retaining portion;
The sheet conveying apparatus according to claim 1. The guide member is slidably held by the holding member with a shaft portion as a fulcrum,
The shaft portion is disposed in the vicinity of the position where the leading edge of the conveyed paper collides,
The sheet conveying apparatus according to claim 1.   The paper conveying apparatus according to claim 1, wherein the holding member includes a restricting portion that restricts movement of the guide member.   The sheet conveying apparatus according to claim 1, wherein the guide member is positioned and fixed to the holding member via the elastic member.

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