JP2010045578A - Image reading apparatus, and image forming apparatus with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus capable of certainly removing paper powder or dust, or the like, adhered to a slit glass without making the load of a drive apparatus increase. <P>SOLUTION: An image reader 10 has a light irradiated to a document passing on a slit glass 13 and reads a document image, based on reflection light from the document. A cleaning rotating body 46 is arranged rotatably on the slit glass 13. The cleaning rotating body 46 has a rotating body 46a that rotates about a rotating center axis which is parallel to the slit glass 13. A first cleaning member 46b and a second cleaning member 46c are provided to the rotating body 46a. Each front end of the cleaning members contacts with the slit glass 13 and bows by the rotation of the rotating body 46a. Each of the first cleaning member 46b and the second cleaning member 46c is arranged, separating by a predetermined distance from each other, in the rotation direction of the rotating body 46a. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image reading apparatus that reads an image of a document and an image forming apparatus including the image reading apparatus.

  As an image reading apparatus that reads an image of an original, an original passing through a contact glass (slit glass) is irradiated with light from a linear light source disposed below the slit glass, and is based on reflected light from the original. With the sheet-through method of reading the image of the original and the original placed on the platen glass, the linear light source and reflecting mirror are slid along the lower surface of the platen glass, and the reflected light from the original is used as a line sensor. There is a mirror scan method that reads the image of the original by guiding it to the end. In a mirror scan type image reading apparatus, it is necessary to slide a linear light source along the lower surface of the platen glass, whereas in a sheet-through type image reading apparatus, an original passes through the slit glass. There is no need to slide the linear light source, the apparatus can be miniaturized, the cost can be reduced, and productivity can be improved. In addition, there is no possibility that noise is generated by sliding the linear light source. An image reading apparatus employing both types has also been developed.

  However, in the sheet-through type image reading apparatus, since the document passing over the slit glass is in sliding contact with the slit glass, there is a problem that paper dust of the document, surrounding dust, etc. are likely to adhere to the slit glass. When paper dust or dust adheres to the slit glass and becomes dirty, this stain was reproduced from the obtained image data in order to always read this dirt when reading a document, even if it is dotted. There is a problem in that streak-like noise is generated in the image in the document transport direction.

  Further, since information is usually written on various types of “paper”, the document is difficult to avoid the occurrence of paper dust in the sheet-through type image reading apparatus in which the document is in sliding contact with the slit glass. It is not easy to reliably prevent paper dust from adhering to the slit glass. In particular, depending on the type of “paper” used in the document, the environment in which it is used, etc., paper dust, dust, and the like may be easily generated. In such a situation, there is a need for a technique that reliably prevents the generation of streak noise in image data.

  Patent Document 1 discloses a sheet-through type image reading apparatus having a configuration for removing paper dust, dust and the like adhering to contact glass. FIG. 10 is a schematic configuration diagram of the image reading apparatus disclosed in Patent Document 1. In FIG. This image reading apparatus is configured to read document information by a reading sensor 82 having a document illuminating means 82a and a light receiving element 82b when a document transported by two pairs of transport rollers 81 and 83 passes over the contact glass 86. It has become. On the contact glass 86, a white roller 84 used for shading correction of the linear light source when reading document information is provided. The outer peripheral surface of the white roller 84 is a white reference surface for reading white reference information. One elastic member 84 a along the main scanning direction (longitudinal direction of the reading sensor 82) is provided on the outer peripheral portion of the white roller 84 over substantially the entire length of the contact glass 86.

  In the image reading apparatus having such a configuration, when the document passes over the contact glass 86, the white roller 84 is rotated to press the document passing over the contact glass 86 against the contact glass 86. . Further, when removing paper dust, dust and the like adhering to the surface of the contact glass 86, the white roller 84 is rotated while the document is not being conveyed. As a result, the elastic member 84a is slid in contact with the contact glass 86, and paper dust, dust and the like attached to the surface of the contact glass 86 are removed. The elastic member 84a is formed of a felt material, a foam material, a cloth or the like so that paper dust, dust and the like can be removed by being pressed against the surface of the contact glass 86.

Further, in Patent Document 1, as shown in FIG. 11, the elastic member 84 a provided on the white roller 84 is elastic so that it is flush with the outer peripheral surface of the white roller 84 when pressed against the contact glass 86. A configuration is also disclosed in which the member 84a is made of a material having a predetermined elasticity, and the white roller 84 is smoothly rotated even when the elastic member 84a is pressed against the contact glass 86.
JP 2000-270152 A

  In Patent Document 1, the white roller 84 is provided with one elastic member 84a along the main scanning direction, and the elastic member 84a is pressed against the contact glass 86 by the rotation of the white roller 84, so that the surface of the contact glass 86 Therefore, the rotational torque of the white roller 84 is increased, and there is a possibility that a large load is applied to a driving device such as a motor for rotating the white roller 84. Further, as shown in FIG. 11, in the configuration in which the elastic member 84a is deformed so as to be flush with the outer peripheral surface of the white roller 84, the elastic member 84a needs to be pressed against the contact glass 86 with a strong force. This also increases the rotational torque of the white roller 84.

  Furthermore, since the paper powder, dust, and the like are removed from the surface of the contact glass 86 by the single elastic member 84a, the paper powder, dust, etc. that have risen from the surface of the contact glass 86 return to the surface of the contact glass 86. May reattach. In this case, with one elastic member 84a, it is necessary to rotate the white roller 84 again in order to remove paper dust, dust, and the like reattached to the contact glass 86, and work efficiency is reduced. In order to prevent paper dust, dust and the like from flying up from the surface of the contact glass 86, a method of increasing the width of one elastic member 84a to further increase the contact area with the contact glass 86, or elasticity A method of strongly pressing the member 84a against the contact glass 86 is conceivable. However, in these cases, the rotational torque of the white roller 84 is further increased, and a large load is applied to the motor for rotating the white roller 84, so that it is necessary to use a larger motor. There is a risk that the apparatus will further increase in size.

  When the document passes over the contact glass 86, the white roller 84 is rotated to press the document against the contact glass 86, and an elastic member 84 a provided on the outer peripheral surface of the white roller 84 includes the document. Will be strongly pressed against. As a result, the conveyance speed of the document becomes unstable, the load on the driving device fluctuates, and there is a possibility that pitch unevenness occurs in the read image data.

  The present invention solves the above-mentioned conventional problems, and its object is to reduce the load on the driving device and to reliably remove paper dust, dust, etc. adhering to the contact glass, It is an object of the present invention to provide an image reading apparatus and an image forming apparatus including the same.

  In order to achieve the above-mentioned object, the present invention irradiates light that is radiated from a linear light source to a document that passes over the contact glass through a contact glass formed in a long plate shape along the linear light source. An image reading apparatus that reads an image of the document based on reflected light from the document, and includes a cleaning rotator that is rotatably disposed on the contact glass, and the cleaning rotator includes: A rotating body main body that is disposed along the contact glass over substantially the entire length of the contact glass and rotates in a non-contact state with the contact glass about a rotation center axis substantially parallel to the contact glass, and the rotating body main body A pair of cleaning members attached along the axial direction of the rotating body main body at a predetermined interval in the rotation direction of the rotating parts, and the pair of cleaning members are rotating directions of the rotating body main body A first cleaning member positioned on the flow side, and a second cleaning member positioned on the upstream side of the rotating body main body in the rotation direction, and the respective distal ends of the first cleaning member and the second cleaning member are The rotating body main body is bent in contact with the contact glass by rotation.

  An image forming apparatus according to the present invention includes the image reading device and an image forming unit that forms an image on a recording sheet based on image data read by the image reading device. To do.

  In the image reading apparatus of the present invention, a pair of cleaning members are attached to the rotating body main body rotating in a non-contact state with the contact glass at a predetermined interval with respect to the rotation direction. Since the contact glass is individually contacted and bent, the load applied to the driving device that rotates the rotating body main body is each when each cleaning member is in pressure contact with the contact glass. Will be distributed. In addition, the force that each cleaning member receives from the contact glass is such that when the pair of cleaning members are provided integrally with no gap in the rotational direction, the integrated cleaning member is bent. Therefore, it becomes smaller than the force received from the contact glass. As a result, it is possible to reduce the load applied to the driving device of the rotating body main body. In addition, even if paper dust, dust, etc. removed from the contact glass rises by the cleaning member arranged on the downstream side in the rotation direction of the cleaning rotating body, the cleaning rotating body rotates even if it adheres to the contact glass again. Since it can remove by the cleaning member arrange | positioned in the direction upstream, work efficiency and workability | operativity can be improved.

Preferably, after the first cleaning member comes into contact with the contact glass by the rotation of the rotating body body, the second cleaning member is moved before the first cleaning member cancels contact with the contact glass. The first cleaning member and the second cleaning member are arranged in a positional relationship in contact with the contact glass.
Preferably, each of the first cleaning member and the second cleaning member is a brush.

Preferably, the rotating body main body is a shaft body having a D-shaped cross section surrounded by a flat surface parallel to the rotation center axis and an outer peripheral surface around the rotation center axis. The first cleaning member and the second cleaning member are attached.
Preferably, a pressure contact force when the second cleaning member contacts the contact glass is larger than a pressure contact force when the first cleaning member contacts the contact glass.

  Preferably, the first cleaning member and the second cleaning member have the same length, and the first cleaning member is inclined at an angle α with respect to a straight line along a radial direction in the rotating body main body. The second cleaning member has an angle β with respect to a straight line along the radial direction in the rotary body main body (note that both α and β are relative to the straight line along the radial direction. The case where it is located on the downstream side in the rotation direction is +, the case where it is located on the upstream side is −, and it is inclined at α−β <0).

Preferably, each of the first cleaning member and the second cleaning member is substantially perpendicular to the flat surface of the rotating body main body.
Preferably, the first cleaning member is longer than the second cleaning member.
Preferably, the amount of bending when the second cleaning member comes into contact with the contact glass is larger than the amount of bending when the first cleaning member comes into contact with the contact glass.

Preferably, the outer peripheral surface of the rotating body main body is opposed to the contact glass at a predetermined interval when the document passes over the contact glass.
Preferably, the outer peripheral surface of the rotating body main body portion is a white reference surface.

  Preferably, the outer peripheral surface of the rotating body main body is opposed to the contact glass at a predetermined interval during shading correction of the linear light source.

Hereinafter, an embodiment of an image forming apparatus provided with an image reading apparatus according to the present invention will be described taking an MFP (Multi Function Peripheral) apparatus as an example.
FIG. 1 is a schematic diagram showing a configuration of an MFP apparatus according to the present embodiment. As shown in FIG. 1, the MFP apparatus includes an image reading apparatus 1, an image forming apparatus 2, and a paper feeding apparatus 3. The image reading apparatus 1 includes an image reading unit 10 having a slit glass 13 and a platen glass 16 provided on the upper surface, and an automatic document feeder (ADF) 40 provided above the image reading unit 10. I have.

  The automatic document transport unit 40 transports the documents placed on the document feed tray 40 a one by one onto the slit glass 13 of the image reading unit 10, and passes through the slit glass 13. The document that has passed over the slit glass 13 is discharged onto the document discharge tray 40b. The image reading unit 10 is a fluorescent lamp 11 that is a linear light source on the image surface of the document conveyed on the slit glass 13 by the automatic document conveyance unit 40 or the image surface of the document placed on the platen glass 16. The line sensor 12 is irradiated via the reduction optical system 15 with the reflected light from the image surface of the document. As a result, the line sensor 12 outputs image data corresponding to the document image. As the fluorescent lamp 11, a rare gas fluorescent lamp such as a xenon lamp, an external electrode fluorescent lamp, or the like is usually used.

The image forming apparatus 2 forms an image based on image data or the like output from the line sensor 12 of the image reading unit 10, and includes an intermediate transfer belt 22 and image forming units 23Y, 23M, 23C, and 23K. I have.
The image forming units 23Y, 23M, 23C, and 23K are arranged along the intermediate transfer belt 22, and respectively yellow (Y), magenta (M), cyan (C), and black (K) toner images. Form. Since the image forming units 23Y to 23K all have the same configuration, only the image forming unit 23K will be described, and thus other description will be given.

  The image forming unit 23K includes a photosensitive drum 24K, a charger 25K, an exposure device 26K, a developing device 27K, and a primary transfer roller 28K. The outer circumferential surface of the photosensitive drum 24K is uniformly charged by the charger 25K. The exposure device 26K emits a light beam toward the photosensitive drum 24K in response to a drive signal based on the image data generated by the image reading unit 10, and exposes and scans the surface of the charged photosensitive drum 24K. An electrostatic latent image is formed on 24K. The electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 24K is developed with toner by the developing device 27K, and the toner image is electrostatically transferred onto the intermediate transfer belt 22 by the primary transfer roller 28K. On the intermediate transfer belt 22, toner images of respective colors Y to K are superimposed and transferred to form a color toner image.

  In parallel with the formation of the color toner image, the sheet feeding device 3 feeds the recording sheets S one by one from any one of the plurality of sheet feeding cassettes 31 accommodated therein, and the secondary transfer roller 21 Transport to the provided secondary transfer position. The secondary transfer roller 21 electrostatically transfers the toner image on the intermediate transfer belt 22 onto the recording sheet S. The recording sheet S to which the toner image is transferred is melted and pressure-bonded to the recording sheet S by heating and pressurization in the fixing device 29 and then discharged onto the recording sheet tray 20a. Residual toner remaining on the intermediate transfer belt 22 without being transferred to the recording sheet S is removed by the cleaner 20b.

  FIG. 2 is a schematic configuration diagram of the image reading apparatus 1. The slit glass 13 provided on the upper surface of the image reading unit 10 has a long plate shape (slit shape) extending long in a direction (main scanning direction) perpendicular to the conveyance direction of the document conveyed by the automatic document conveyance unit 40. The image reading unit 10 is provided on the side portion on the upstream side in the document conveyance direction (sub-scanning direction). The platen glass 16 on which the document is placed is provided downstream of the slit glass 13 in the document transport direction (sub-scanning direction) with an appropriate interval from the slit glass 13.

  The document D placed on the document feed tray 40 a of the automatic document transport unit 40 is sent out from the document feed tray 40 a to the transport path 49 by the pickup roller 42 and transported to the separation roller pair 43. The separating roller pair 43 includes a separating roller 43a and a sheet feeding roller 43b. The separating roller pair 43 separates the document D conveyed between the separating roller 43a and the sheet feeding roller 43b one by one and forms a registration roller pair 44. Transport to. The registration roller pair 44 conveys one conveyed document D to a pre-reading roller pair 45 at a predetermined timing and at a predetermined timing.

  The pre-reading roller pair 45 conveys the document D toward the slit glass 13 at a predetermined timing and passes it over the surface of the slit glass 13. A cleaning rotator 46 is provided on the slit glass 13 to clean the surface of the slit glass 13 by being rotated at a timing when the document D is not conveyed. When the document D is conveyed by the pre-reading roller pair 45, the cleaning rotator 46 is in a non-contact state (the state shown in FIG. 2) in which a space is formed between the slit glass 13 and The document D passes through the space and is conveyed to the roller pair 47 after reading.

  The document D conveyed on the slit glass 13 by the pair of pre-reading rollers 45 is detected by the sensor 41 before reading, and the leading edge and the trailing edge of the document D are detected by the sensor 41 before reading. Thus, the image reading timing in the image reading unit 10, the rotation of the cleaning rotator 46, and the like are controlled. The pre-reading roller pair 45 and the post-reading roller pair 47 pass the document D over the slit glass 13 at a predetermined speed. After reading, the document D that has passed through the roller pair 47 is discharged onto the paper discharge tray 40 b by the paper discharge roller pair 48.

  Below the slit glass 13 provided in the image reading unit 10, a fluorescent lamp 11 as a linear light source is configured to be slidable in a direction indicated by an arrow A in a state along the main scanning direction. 18 is mounted. When reading the document D transported by the automatic document transport unit 40, the first slider 18 is in a state where the fluorescent lamp 11 is located at a predetermined sheet through position below the slit glass 13, as shown in FIG. Stopped. On the other hand, when reading the document on the platen glass 16, it is moved in the direction indicated by the arrow A in FIG.

  The reduction optical system 15 reflects the reflected light from the original passing through the slit glass 13 or the original placed on the platen glass 16 at a substantially right angle in the direction opposite to the direction indicated by the arrow A. And a pair of second mirror 15c and third mirror 15d that inverts the light reflected by the first mirror 15b in the direction of arrow A, and a pair of second mirror 15c and third mirror 15d in the direction of arrow A. A reduction lens 15e for reducing and projecting the inverted light onto the line sensor 12; The first mirror 15b is mounted on the first slider 18 together with the fluorescent lamp 11, and the second mirror 15c and the third mirror 15d are mounted on a second slider 19 configured to be slidable in the direction indicated by the arrow A. It is installed.

  The line sensor 12 is configured by mounting a CCD (Charge Coupled Device) having a plurality of photoelectric conversion elements arranged along the main scanning direction on a substrate. The line sensor 12 is in a state along the longitudinal direction of the fluorescent lamp 11 so that light irradiated from the fluorescent lamp 11 along the main scanning direction and reflected by the document is projected in a reduced state by the reduction optical system 15. Thus, it is disposed opposite to the third mirror 15d via the reduction lens 15e.

  When reading an image of a document placed on the platen glass 16, the first slider 18 is slid in the direction indicated by the arrow A along the lower surface of the platen glass 16, and the second slider 19 is The slider 18 is slid along the same direction at a speed of 1/2 following the slider 18. As a result, the image of the document placed on the platen glass 16 is read by the line sensor 12.

  FIG. 3 is a cross-sectional view illustrating a specific configuration of a main part in the image reading apparatus 1, and FIG. 4 is a schematic diagram illustrating a configuration of the cleaning rotating body 46. The cleaning rotator 46 disposed on the slit glass 13 includes a rotator main body 46a, which is a shaft disposed along the main scanning direction (corresponding to a direction perpendicular to the paper surface) above the slit glass 13, and a rotator. A first cleaning member 46b and a second cleaning member 46c attached to the main body 46a are provided.

  The rotating body main body 46a has, for example, a shape in which a part of a metal cylinder is cut out by a flat surface 46d parallel to the axis, and accordingly, the flat surface 46d parallel to the axis O and the shaft It has a D-shaped cross section surrounded by an outer peripheral surface 46e centered on the center O. The rotator main body 46a is rotated in the direction indicated by the arrow B in FIGS. 3 and 4 by a rotation drive device, for example, a stepping motor, with the axis O as the rotation center axis. The axis (rotation center axis) O of the rotator main body 46 a is disposed on the passage position (reading position) of light reflected by the document D passing on the slit glass 13 and guided to the line sensor 12.

  The outer peripheral surface 46e of the rotator main body 46a is brought into a facing state with a predetermined distance from the slit glass 13 by rotating the rotator main body 46a by a stepping motor. The outer peripheral surface 46e of the rotator main body 46a is in a state of facing the slit glass 13 so that a minimum interval of about 1 to 2 mm is left with respect to the slit glass 13. The outer peripheral surface 46e of the rotating body main body 46a is, for example, a white reference surface by attaching a white PET film, and the rotating body main body 46a performs the shading correction of the fluorescent lamp 11, and When the document D passes over the slit glass 13, the outer peripheral surface 46 e is rotationally driven so as to face the slit glass 13 and stopped. An outer peripheral surface position detection sensor (not shown) for detecting that the outer peripheral surface 46e of the rotating body main body 46a is opposed to the slit glass 13 is provided at one end in the longitudinal direction of the rotating body main body 46a. The rotation of the rotating body main body 46a is controlled based on the detection signal from the outer peripheral surface position detection sensor.

  For example, as shown in FIG. 4, the first cleaning member 46 b and the second cleaning member 46 c are flat surfaces 46 d that pass through the rotation center axis O of the rotating body main body 46 a with respect to the flat surface 46 d of the rotating body main body 46 a. Are attached to the flat surface 46d on both sides of the vertical line L so as to be substantially parallel to the vertical line L. The first cleaning member 46b is disposed on the downstream side in the rotation direction of the rotating body main body 46a with respect to the second cleaning member 46c. The 1st cleaning member 46b and the 2nd cleaning member 46c are comprised by the brush which will be in the state where each front-end | tip part contacted the surface of the slit glass 13 by rotation of the rotary body main body part 46a. Each brush is attached to the flat surface 46d of the rotator main body 46a with conductive fibers extending along the main scanning direction over substantially the entire length of the slit glass 13 with a constant width (for example, about 2 mm). ing.

  The length of the 1st cleaning member 46b and the 2nd cleaning member 46c is respectively larger than the space | interval with the surface of the slit glass 13 when the flat surface 46d of the rotary body main-body part 46a becomes parallel to the surface of the slit glass 13. The length is about 1.5 mm. Therefore, when the rotator main body 46a rotates, the respective front end portions slide on the surface of the slit glass 13, and as a result, the respective front end portions are bent as shown in FIG. Further, the interval between the first cleaning member 46b and the second cleaning member 46c is such that the first cleaning member 46b brought into contact with the slit glass 13 by the rotation of the rotating body main body 46a cancels the contact with the slit glass 13. The second cleaning member 46c is set so as to come into contact with the slit glass 13 before the operation.

  In the image reading apparatus 1 having such a configuration, when the shading correction of the fluorescent lamp 11 is performed before the image of the document is read, the outer peripheral surface 46e of the rotating body main body 46a in the cleaning rotating body 46 is formed on the slit glass 13. The rotating body main body 46a is rotated so as to face each other, and the outer peripheral surface 46e of the rotating body main body 46a is stopped in a state where a minimum interval of about 1 to 2 mm is formed between the slit glass 13. When the fluorescent lamp 11 is turned on in such a state, the light emitted from the fluorescent lamp 11 is reflected on the outer peripheral surface of the rotating body main body 46 a and projected onto the line sensor 12 via the reduction optical system 15. The The output of the line sensor 12 corresponds to the intensity of the reflected light from the outer peripheral surface 46e which is a white reference surface, and shading correction is performed so that the output is uniform in the longitudinal direction of the fluorescent lamp 11.

  When the image reading unit 10 reads an image of the document D transported by the automatic document transport unit 40, the outer peripheral surface 46e of the rotating body main body 46a of the cleaning rotating body 46 is the slit glass 13 as in the shading correction. The rotating body main body 46a is rotated so as to face the surface. As a result, a minimum interval of about 1 to 2 mm is formed between the outer peripheral surface 46e of the rotating body main body 46a and the slit glass 13. In this state, the fluorescent lamp 11 is turned on, and the document D passes over the slit glass 13. The document D passing over the slit glass 13 reflects the light emitted from the fluorescent lamp 11, and the reflected light is projected onto the line sensor 12 via the reduction optical system 15. As a result, the image on the image surface of the document D is read and image data corresponding to the image is obtained.

In this case, even if the document D is thin and made of a material that transmits light, the outer peripheral surface 46e of the rotating body main body 46a facing the slit glass 13 is a white reference surface. The transmitted light is reliably reflected by the outer peripheral surface 46e of the rotator main body 46a, and the attenuation of the intensity of the reflected light due to the light passing through the document D is suppressed.
In this way, when the pre-reading sensor 41 detects that the document D has passed over the slit glass 13 and image data on the image surface of one document D is obtained, the cleaning rotator 46 rotates. The body main body 46a is rotated once by the stepping motor. As shown in FIG. 5 (a), the first cleaning member 46b and the second cleaning member 46c are not in contact with the slit glass 13 as shown in FIG. Thus, only the 1st cleaning member 46b will be in the state which contacted the slit glass 13, and slides the slit glass 13 surface. The 1st cleaning member 46b comprised with the brush will be in the state which the front-end | tip part bent by contacting and sliding on the surface of the slit glass 13, and the paper powder, dust, etc. of the slit glass 13 surface bent. The first cleaning member 46b in the state is peeled off from the surface of the slit glass 13 by the tip of the first cleaning member 46b.

  Thereafter, the rotating body body 46a further rotates in the direction indicated by the arrow B, so that the second cleaning member 46c comes into contact with the slit glass 13 before the first cleaning member 46b cancels the contact with the slit glass 13. And begin to slide. Thereby, since the 1st cleaning member 46b and the 2nd cleaning member 46c contact the slit glass 13 simultaneously, as shown in FIG.5 (c), the 2nd comprised by the brush similarly to the 1st cleaning member 46b. When the cleaning member 46c comes into contact with the slit glass 13 and slides, the tip end portion is bent, and the remaining paper powder, dust, etc. that could not be separated by the first cleaning member 46b are removed from the surface of the slit glass 13. Is peeled off. Thereafter, the rotating body body 46a is further rotated, so that the first cleaning member 46b is not in contact with the slit glass 13. As a result, the bent state of the tip of the first cleaning member 46b is released, and paper dust, dust and the like peeled off from the surface of the slit glass 13 are removed from the surface of the slit glass 13.

  In this case, there is a possibility that paper dust, dust, and the like peeled off from the surface of the slit glass 13 may rise in the air and reattach to the surface of the slit glass 13. However, on the upstream side in the rotation direction of the rotating body main body 46a, the second cleaning member Since the surface of the slit glass 13 is slid in a state in which 46c is bent, paper dust, dust, and the like that have reattached to the surface of the slit glass 13 are peeled off from the surface of the slit glass 13 by the second cleaning member 46c. Taken. After that, the second cleaning member 46c does not come into contact with the surface of the slit glass 13 along with the rotation of the rotating body main body 46a, and when the bent state of the tip of the second cleaning member 46c is released, the surface of the slit glass 13 The paper powder, dust, etc. peeled from the surface are removed from the surface of the slit glass 13. Thereby, the surface of the slit glass 13 will be in the clean state in which paper dust, dust, etc. have not adhered.

  When the rotator main body 46a of the cleaning rotator 46 rotates once, the rotation of the rotator main body 46a is stopped. As a result, the outer peripheral surface 46e of the rotating body main body 46a is in a state of facing the slit glass 13, and then a new original D is conveyed onto the slit glass 13 so that an image on the image surface of the original D is obtained. Read. In this case, since the slit glass 13 is in a clean state in which paper dust, dust, and the like are not attached by the first cleaning member 46b and the second cleaning member 46c, the slit glass 13 becomes image data output from the line sensor 12. There is no risk of streaking noise. Thereafter, reading of an image on the image surface of the document D and cleaning of the surface of the slit glass 13 are repeated.

  As described above, since the pair of first cleaning member 46b and second cleaning member 46c are provided on the cleaning rotating body 46 at a predetermined interval in the rotation direction, the respective leading end portions are formed on the slit glass 13. It will be in the state where it pressed by the surface of each and bent. Therefore, a load applied to a driving device such as a stepping motor that rotationally drives the rotating body main body 46 a is dispersed when each of the first cleaning member 46 b and the second cleaning member 46 c is pressed against the slit glass 13. Moreover, since each of the first cleaning member 46b and the second cleaning member 46c is constituted by a brush and is bent by being pressed against the slit glass 13, each of the first cleaning member 46b and the second cleaning member 46c. As a result, the load on the drive device that rotates the rotating body main body 46a can be further reduced. Thereby, it is not necessary to increase the size of the driving device, and a small driving device can be used, and the entire image reading apparatus 1 can be reduced in size. Further, since the surface of the slit glass 13 is cleaned by bending the first cleaning member 46b and the second cleaning member 46c, it is necessary to strongly press the first cleaning member 46b and the second cleaning member 46c against the surface of the slit glass 13. The deformation of the first cleaning member 46b and the second cleaning member 46c can be suppressed, and the durability of each can be improved. Moreover, since each is comprised with the brush, there is no possibility that the slit glass 13 may be scraped.

  FIGS. 6A to 6C are schematic views for explaining the operation in the comparative example in which one cleaning member 46f is provided in the rotating body main body 46a of the cleaning rotating body 46. FIG. As shown in FIG. 6A, the cleaning member 46f is rotated from the state where it does not come into contact with the slit glass 13 as shown in FIG. It will be in the state of sliding in contact with the surface. The cleaning member 46 f constituted by the brush is in a state where the tip portion is bent by sliding on the surface of the slit glass 13, and peels off paper dust, dust and the like on the surface of the slit glass 13 from the surface of the slit glass 13. Thereafter, as shown in FIG. 6 (c), the cleaning member 46f eliminates the contact with the surface of the slit glass 13 and eliminates the bending state of the cleaning member 46f, whereby the paper powder peeled off from the surface of the slit glass 13; Dust and the like are swept from the surface of the slit glass 13.

  In this case, since only one cleaning member 46f is provided, there is a possibility that paper dust, dust, etc. adhering to the surface of the slit glass 13 may not be reliably removed, and it has been removed from the slit glass 13. There is a risk that paper dust, dust, etc. will rise and re-attach to the surface of the slit glass 13. On the other hand, in the configuration of the embodiment of the present invention in which two of the first cleaning member 46b and the second cleaning member 46c are provided, as described above, paper dust, dust, and the like attached to the surface of the slit glass 13 are removed. It can be removed reliably. Further, even if paper dust, dust, or the like that has risen from the surface of the slit glass 13 reattaches to the slit glass 13, the paper dust, dust, etc. that have reattached can be removed by the second cleaning member 46c. In particular, since the second cleaning member 46c comes into contact with the surface of the slit glass 13 before the first cleaning member 46b does not come into contact with the surface of the slit glass 13, paper dust, dust, etc. There is no possibility of scattering to the upstream side in the rotational direction of the cleaning member 46c, and this can also reliably remove paper dust, dust and the like from the surface of the slit glass 13.

  In the above embodiment, the first cleaning member 46b and the second cleaning member 46c of the cleaning rotator 46 are provided substantially perpendicular to the flat surface 46d of the rotator body 46a. Is not limited to such a configuration. For example, as shown in FIG. 7, the first cleaning member 46b is inclined with respect to a line R1 (hereinafter referred to as a radial line) R1 along the radial direction of the rotating body main body 46a. The second cleaning member 46c is inclined via the vertical line L of the rotating body main body 46a. An inclination angle β on the downstream side in the rotational direction of the rotating body main body 46a with respect to the radial line R2 that is symmetrical to the radial line R1 (however, the downstream side in the rotational direction of the rotating body main body 46a with respect to R2 It may be configured such that the position is located at +, the case located at the upper side is −, and the inclination is α−β <0).

  If α−β <0, the first cleaning member 46b and the second cleaning member 46c are separated from the slit glass 13 as shown in FIG. 8A by the rotation of the rotating body main body 46a. 8 (b), the first cleaning member 46b comes into contact with the slit glass 13 and slides. Thereafter, as shown in FIG. 8C, the second cleaning member 46 c comes into contact with the slit glass 13 and slides, and the first cleaning member 46 b does not come into contact with the slit glass 13 and enters the second state. 1 The bending state of the cleaning member 46b is released.

  In this case, the first cleaning member 46b is inclined at an angle α on the upstream side in the rotational direction of the rotating body main body 46a with respect to the radial line R1, whereas the second cleaning member 46c is in the radial line. Since it is inclined at an angle β (> α) with respect to R2, the second cleaning member 46c formed of a brush is pressed against the slit glass 13 more strongly than the first cleaning member 46b. Thereby, paper dust, dust, etc. adhering to the surface of the slit glass 13 can be reliably peeled from the surface of the slit glass 13 more reliably. Thereafter, when the second cleaning member 46c is not in contact with the surface of the slit glass 13 and the bent state of the tip is released, the paper powder, dust, etc. peeled from the surface of the slit glass 13 are removed. Removed from the surface.

  In the above embodiment, the first cleaning member 46b and the second cleaning member 46c have the same length. However, as shown in FIG. 9, the first cleaning member 46b is more than the second cleaning member 46c. It is good also as a structure to lengthen. In this case, the first cleaning member 46b is attached perpendicularly to the flat surface 46d along the radial line of the rotating body main body 46a, and the second cleaning member 46c is shorter than the first cleaning member 46b. The first cleaning member 46b is attached perpendicularly to the flat surface 46d at a predetermined interval. Then, the lengths of the first cleaning member 46b and the second cleaning member 46c are set so that the tip of the first cleaning member 46b and the tip of the second cleaning member 46c move on the same circle by the rotation of the rotating body main body 46a. With such a configuration, paper dust, dust and the like can be reliably removed from the surface of the slit glass 13.

  Moreover, in the said embodiment, although it was the structure which provides a pair of 1st cleaning member 46b and the 2nd cleaning member 46c in the rotary body 46 for cleaning, between the 1st cleaning member 46b and the 2nd cleaning member 46c, or One or more cleaning members may be provided outside each of the first cleaning member 46b and the second cleaning member 46c. Further, the first cleaning member 46b and the second cleaning member 46c are not limited to brushes, and an elastic body such as a rubber blade is used as long as the tip portion is bent by contact with the slit glass 13. May be. The shape of the rotating body main body 46a is not particularly limited, and may be a shaft body having a square cross section.

  Furthermore, although the outer peripheral surface of the rotator main body 46a is used in combination as a white reference surface for shading correction, the present invention is not limited to this. In addition, each time a document is read, the rotating body main body 46a is rotated once between the end of reading the previous document and before the next document is read. It is not limited. For example, a configuration may be adopted in which the rotating body main body 46a is rotated once before the reading of the first document is started, or the rotating body main body 46a is rotated once when the power is turned on.

  In the above embodiment, the MFP apparatus has been described as an image forming apparatus provided with an image reading apparatus. However, the present invention is not limited to this, and the present invention can also be applied to an image forming apparatus such as a copying machine or a facsimile. The image reading apparatus is not limited to the image forming apparatus, and may be an image reading apparatus having only an image reading function.

  The present invention can reliably remove paper dust, dust, and the like adhering to the contact glass without increasing the size of the drive device in an image reading apparatus that reads an image of a document passing over the contact glass.

1 is a schematic configuration diagram of an MFP apparatus which is an example of an image forming apparatus provided with an image reading apparatus according to the present invention. 1 is a schematic configuration diagram of an image reading apparatus according to an embodiment of the present invention. It is sectional drawing which shows the specific structure of the principal part in the image reading apparatus. It is sectional drawing which shows schematic structure of the rotary body for cleaning provided in the image reading apparatus. (A)-(c) is each operation | movement explanatory drawing of the rotary body for cleaning. (A)-(c) is operation | movement explanatory drawing of the rotary body for cleaning of a comparative example, respectively. It is sectional drawing which shows schematic structure in the other example of the rotary body for cleaning provided in the image reading apparatus. (A)-(c) is operation | movement explanatory drawing of the rotary body for cleaning, respectively. It is sectional drawing which shows schematic structure of the other example of the rotary body for cleaning. It is sectional drawing which shows schematic structure in the conventional image reading apparatus. It is sectional drawing which shows schematic structure of the principal part of the other example in the conventional image reading apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image reading apparatus 2 Image forming apparatus 3 Paper feeder 10 Image reading part 11 Fluorescent lamp 12 Line sensor 13 Slit glass 15 Reduction optical system 18 First slider 19 Second slider 40 Automatic document conveyance part 45 Pre-reading roller pair 46 For cleaning Rotating body 46a Rotating body main body 46b First cleaning member 46c Second cleaning member 46d Flat surface 46e Outer peripheral surface 47 Post-reading roller pair

Claims (13)

Based on the reflected light from the original by irradiating the light irradiated from the linear light source to the original passing through the contact glass through the contact glass formed in a long plate shape along the linear light source. An image reading device for reading an image of the original,
A cleaning rotator disposed rotatably on the contact glass;
The cleaning rotator is
A rotating body main body that is disposed along the contact glass over substantially the entire length of the contact glass and rotates in a non-contact state with the contact glass about a rotation center axis substantially parallel to the contact glass;
A pair of cleaning members attached along the axial direction of the rotating body main body with a predetermined interval in the rotating direction of the rotating body main body;
Have
The pair of cleaning members are a first cleaning member located on the downstream side in the rotation direction of the rotating body main body and a second cleaning member located on the upstream side in the rotation direction of the rotating body main body,
The image reading apparatus according to claim 1, wherein respective distal end portions of the first cleaning member and the second cleaning member are bent in contact with the contact glass by rotation of the rotating body main body portion.   After the first cleaning member comes into contact with the contact glass by the rotation of the rotating body main body, the second cleaning member is brought into contact with the contact glass before the first cleaning member cancels contact with the contact glass. The image reading apparatus according to claim 1, wherein the first cleaning member and the second cleaning member are arranged in a positional relationship in contact with each other.   The image reading apparatus according to claim 1, wherein each of the first cleaning member and the second cleaning member is a brush.   The rotating body main body is a shaft body having a D-shaped cross section surrounded by a flat surface parallel to the rotation center axis and an outer peripheral surface having the rotation center axis as a center. The image reading apparatus according to claim 1, wherein a cleaning member and the second cleaning member are attached.   The pressure contact force when the second cleaning member contacts the contact glass is larger than the pressure contact force when the first cleaning member contacts the contact glass. The image reading apparatus according to any one of the above. The first cleaning member and the second cleaning member have the same length,
The first cleaning member is inclined at an angle α with respect to a straight line along the radial direction of the rotating body main body, and the second cleaning member is relative to a straight line along the radial direction of the rotating body main body. An angle β (provided that both α and β are positioned on the downstream side in the rotational direction of the rotating body main body with respect to the straight line along the radial direction as +, and when positioned on the upstream side, − , Α−β <0), and the image reading apparatus according to claim 4.   The image reading apparatus according to claim 4, wherein each of the first cleaning member and the second cleaning member is substantially perpendicular to the flat surface of the rotating body main body.   The image reading apparatus according to claim 7, wherein the first cleaning member is longer than the second cleaning member.   The amount of bending when the second cleaning member comes into contact with the contact glass is larger than the amount of bending when the first cleaning member comes into contact with the contact glass. Image reading apparatus.   5. The image reading according to claim 4, wherein the outer peripheral surface of the rotating body main body is opposed to the contact glass at a predetermined interval when the document passes over the contact glass. apparatus.   The image reading apparatus according to claim 10, wherein the outer peripheral surface of the rotating body main body is a white reference surface.   The image reading apparatus according to claim 11, wherein the outer peripheral surface of the rotating body main body is opposed to the contact glass at a predetermined interval during shading correction of the linear light source. An image reading apparatus according to any one of claims 1 to 12,
An image forming unit that forms an image on a recording sheet based on image data read by the image reading device;
An image forming apparatus comprising:

Images