JP2010210749A - Image reader and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reader equipped with a light emitting part in which a plurality of light emitting members are arranged in a main scanning direction, and a light guide body, which is capable of suppressing uneven intensity of light that enters a reading part, and an image forming apparatus equipped with the image reader. <P>SOLUTION: The image reader 300 comprises a light emitting part 501 having a plurality of light emitting members arranged at a predetermined interval in a main scanning direction Y such that the light emitting surface faces a document G side, and a light guide body 505 disposed between the light emitting part 501 and the document G, having a light entrance part 400 disposed on the light emitting part 501 side and a light exit part 410 disposed on the document G side. In the light guide body 505, the distance between the light entrance part 400 and the light exit part 410 in a first light guide part 508 located on an edge part side in the main scanning direction Y, and the distance between the light entrance part 400 and the light exit part 410 in a second light guide part 509 located in the central part in the main scanning direction Y are different. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image reading apparatus and an image forming apparatus including the image reading apparatus.

  Conventionally, as an image reading apparatus that reads an image of a document, an illumination unit that irradiates light on the document, a mirror that reflects light from the document to form an optical path, an imaging lens that forms an image of a light beam from the document, 2. Description of the Related Art An image reading apparatus including a CCD (Charge-Coupled Device) that reads an image of an original image formed by an imaging lens is known.

  In addition to tubular light-emitting members such as fluorescent lamps and xenon tubes, light-emitting members such as LEDs (Light-Emitting Diodes) are used as the light-emitting units that constitute the illumination unit. For example, an image reading apparatus is known in which an illumination unit is configured by arranging a plurality of LEDs in the main scanning direction.

In the illuminating unit in which a plurality of LEDs are arranged in the main scanning direction, there is a problem that the light amount on the end side in the main scanning direction is smaller than the light amount in the central part. In this regard, for example, an image reading apparatus is proposed in which LEDs having different light distribution characteristics from the central portion are arranged on the end side in the main scanning direction so as to increase the amount of light on the end side in the main scanning direction. (For example, refer to Patent Document 1).
In order to effectively use light from a plurality of LEDs, an image reading apparatus having a light guide that guides light from the plurality of LEDs to the document side has been proposed (for example, see Patent Document 2).

JP 2004-177851 A JP 2008-35036 A

  However, in the case of an illumination unit in which a plurality of types of LEDs having different light distribution characteristics are arranged, there is a problem that costs increase. Moreover, since it becomes an illumination part which superimposes the light from LED from which a light distribution characteristic differs, the light distribution nonuniformity (light quantity nonuniformity) may arise. Further, in the image reading apparatus of Patent Document 2, the light guide has no device for uneven light distribution (uneven light amount).

SUMMARY OF THE INVENTION An object of the present invention is to provide an image reading apparatus capable of suppressing unevenness in the amount of light incident on a reading section in an image reading apparatus including a light emitting section and a light guide that arrange a plurality of light emitting members in the main scanning direction. And
Another object of the present invention is to provide an image forming apparatus including the image reading apparatus.

  The present invention provides a light emitting unit having a plurality of light emitting members arranged at predetermined intervals in the main scanning direction so that the light emitting surface faces the document side, and is disposed between the light emitting unit and the document, and the light emitting unit A light guide having a light incident portion disposed on the side and a light exit portion disposed on the document side, wherein the light incident portion in the first light guide portion located on the end side in the main scanning direction A light guide having a different distance from the light exit portion and a distance between the light entrance portion and the light exit portion in the second light guide portion located in the center in the main scanning direction, and a light flux from the original Are arranged at the imaging position of the imaging lens, the imaging lens for imaging the light beam reflected by the one or more mirrors, and the imaging lens. A reading unit that reads an image of the document based on image formation by a lens. That relates to an image reading apparatus.

  Moreover, it is preferable that the said light guide is the concave shape in which the said light entrance part is dented in the said light emission part side in the said center part.

  Moreover, it is preferable that the light guide is hollow and has a concave shape in which the light exit portion is recessed toward the light incident portion in the center portion.

  Further, it is preferable that the light guide has a solid shape having a light-transmitting member and has a convex shape in which the light output portion projects toward the document side at the central portion.

  The present invention provides a light emitting unit having a plurality of light emitting members arranged at predetermined intervals in the main scanning direction so that the light emitting surface faces the document side, and is disposed between the light emitting unit and the document, and the light emitting unit A light incident portion disposed on the side, a light exit portion disposed on the document side, a first light guide portion located on the end side in the main scanning direction, and a second light guide located in the center portion in the main scanning direction. A light part, a hollow part formed so as to connect the light incident part and the light exit part and long in the main scanning direction, and a first light reflecting part having a predetermined light reflectance formed on the inner surface of the hollow part. And the distance between the light incident part and the light exit part in the first part corresponding to the first light guide part, the light incident part in the second part corresponding to the second light guide part, and the A hollow light guide having a first light reflecting portion having a different distance from the light emitting portion, and a light flux from the original. One or a plurality of mirrors that project light to form an optical path; an imaging lens that forms an image of a light beam reflected by the one or more mirrors; and an imaging lens disposed at an imaging position of the imaging lens, The present invention relates to an image reading apparatus including a reading unit that reads an image of the document based on the image formed by the above.

  In the first light reflecting portion, the distance between the light incident portion and the light exit portion in the second portion is shorter than the distance between the light entrance portion and the light exit portion in the first portion. It is preferable to be formed as follows.

  Further, the light guide has a second light reflection having a light reflectance lower than that of the first light reflection portion on the light incident portion side and / or the light exit portion side of the second portion on the inner surface of the hollow portion. It is preferable to have a part.

  The light guide has a substantially uniform distance between the light incident portion and the light exit portion in the main scanning direction, and the second light reflecting portion is the light incident on the first light reflecting portion. It is preferable to arrange on the part side.

  The present invention provides a light emitting unit having a plurality of light emitting members arranged at predetermined intervals in the main scanning direction so that the light emitting surface faces the document side, and is disposed between the light emitting unit and the document, and the light emitting unit A light incident portion disposed on the side, a light exit portion disposed on the document side, a first light guide portion located on the end side in the main scanning direction, and a second light guide located in the center portion in the main scanning direction. A light transmitting portion formed of a light transmitting member formed so as to connect the light portion, the light incident portion, and the light exiting portion, and is long in the main scanning direction, and corresponds to the second light guide portion. A solid light guide having a light transmissive portion having a light transmittance of the two transmissive portions lower than the light transmittance of the first transmissive portion corresponding to the first light guide portion, and reflecting the light flux from the document An image of one or more mirrors that form an optical path and the light beam reflected by the one or more mirrors. An imaging lens, are arranged at an imaging position of the imaging lens, an image reading apparatus and a reading section to read an image of the document on the basis of imaging by the imaging lens.

  The present invention provides an image carrier on which an electrostatic latent image is formed on the surface based on image information relating to the image of the original read by the image reading device, and an electrostatic latent image formed on the image carrier. A developing unit that develops the toner image, a transfer unit that directly or indirectly transfers the toner image formed on the image carrier to a predetermined sheet, and the toner that is transferred to the predetermined sheet by the transfer unit The present invention relates to an image forming apparatus including a fixing unit that fixes an image.

According to the present invention, in an image reading apparatus including a light emitting unit and a light guide that array a plurality of light emitting members in the main scanning direction, an image reading apparatus capable of suppressing light amount unevenness of light entering the reading unit is provided. Can do.
In addition, according to the present invention, an image forming apparatus including the image reading apparatus can be provided.

2 is a diagram for explaining the arrangement of each component of the copier 1. FIG. 3 is a schematic plan view showing an internal structure of a reading unit 301 of the image reading apparatus 300. FIG. FIG. 3 is a view of the image reading apparatus 300 shown in FIG. 2 as viewed from the direction of an arrow S. It is the elements on larger scale of the light guide 505 shown in FIG. It is a perspective view of the LED unit 503 shown in FIG. FIG. 6 is a diagram illustrating a case where a light guide body 505 is arranged with a light incident section 400 facing a plurality of LEDs 501 and a light exit section 410 facing a document G. It is a figure which shows the light quantity distribution in the main scanning direction Y when not arrange | positioning a light guide. It is the elements on larger scale which show light guide 505A. It is the elements on larger scale which show the light guide 505B. It is the elements on larger scale which show light guide 505C. It is the elements on larger scale explaining light guide 505D which has a transparent member and is formed in solid. It is the elements on larger scale which show the light guide 505E which has a light-transmitting member and is formed in a solid shape. It is the elements on larger scale which show the light guide 505F which has a light-transmitting member and is formed in a solid shape.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 6B.
With reference to FIG. 1, the overall structure of a copier 1 as an image forming apparatus in the present embodiment will be described. FIG. 1 is a diagram for explaining the arrangement of each component of the copier 1.

  As shown in FIG. 1, a copying machine 1 as an image forming apparatus includes an image reading device 300 arranged on the upper side of the copying machine 1 and image information from the image reading device 300 arranged on the lower side of the copying machine 1. And an apparatus main body M that forms a toner image on a sheet T as a sheet-like transfer material.

The image reading apparatus 300 will be described.
As shown in FIG. 1, the image reading apparatus 300 includes a lid member 70 and a reading unit 301 that reads an image of a document G.
The lid member 70 is connected to the reading unit 301 so as to be opened and closed by a connecting unit (not shown). The lid member 70 has a function of protecting a reading surface 302A described later.

  The reading unit 301 includes a reading surface 302A, an illumination unit 340 including a light source disposed in the internal space 304, a plurality of mirrors 321, 322, and 323, and a first frame 311 that moves in a direction parallel to the reading surface 302A. And the second frame 312, the imaging lens 357, the CCD 358 as reading means, and a CCD substrate that performs predetermined processing on the image data read by the CCD 358 and outputs the image data to the apparatus main body M side. 361.

The reading surface 302A is formed along the upper surface in the vertical direction of the contact glass 302 on which the document G is placed.
The illumination unit 340 and the mirror 321 described above are accommodated in the first frame 311. The mirrors 322 and 323 are accommodated in the second frame 312.

  In the internal space 304 of the reading unit 301, the plurality of mirrors 321, 322, and 323 form an optical path H for allowing light from the original G to enter the imaging lens 357. In addition, the first frame 311 moves at a constant speed A in the sub-scanning direction X, and the second frame 312 moves at a constant speed A / 2 in the sub-scanning direction X. The length of H is kept constant. Thereby, the image of the original G placed on the reading surface 302A is read.

The apparatus main body M will be described.
The apparatus main body M is configured to form a predetermined toner image on the paper T based on predetermined image information, and to feed the paper T to the image forming unit and to discharge the paper T on which the toner image is formed. And a paper supply / discharge unit.

  As shown in FIG. 1, the image forming unit includes photosensitive drums 2a, 2b, 2c, and 2d as image carriers (photosensitive members), charging units 10a, 10b, 10c, and 10d, and a laser scanner as an exposure unit. Units 4a, 4b, 4c, 4d, developing devices 16a, 16b, 16c, 16d, toner cartridges 5a, 5b, 5c, 5d, toner supply units 6a, 6b, 6c, 6d, and drum cleaning units 11a, 11b 11c, 11d, static eliminators 12a, 12b, 12c, 12d, intermediate transfer belt 7, primary transfer rollers 37a, 37b, 37c, 37d, secondary transfer roller 8, counter roller 18 and fixing unit 9.

  As shown in FIG. 1, the paper feed / discharge unit includes a paper feed cassette 52, a manual paper feed unit 64, a conveyance path L for paper T, a registration roller pair 80, a first paper discharge unit 50 a, and a second paper feed unit. A paper discharge unit 50b. As will be described later, the transport path L includes a first transport path L1, a second transport path L2, a third transport path L3, a manual transport path La, a return transport path Lb, and a post-processing transport path Lc. Is a collection of

Hereinafter, each configuration of the image forming unit and the paper supply / discharge unit will be described in detail.
First, the image forming unit will be described.
In the image forming unit, charging by the charging units 10a, 10b, 10c, and 10d in order from the upstream side to the downstream side with respect to the respective surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, and the laser scanner units 4a, 4b, 4c, 4d exposure, development devices 16a, 16b, 16c, 16d development, intermediate transfer belt 7 and primary transfer rollers 37a, 37b, 37c, 37d primary transfer, static eliminators 12a, 12b, 12c, 12d And cleaning by the drum cleaning units 11a, 11b, 11c, and 11d.
In the image forming unit, secondary transfer by the intermediate transfer belt 7, the secondary transfer roller 8 and the counter roller 18, and fixing by the fixing unit 9 are performed.

  Each of the photosensitive drums 2a, 2b, 2c, and 2d is formed of a cylindrical member and functions as a photosensitive member or an image carrier. Each of the photosensitive drums 2 a, 2 b, 2 c, and 2 d is disposed so as to be rotatable in the direction of an arrow about an axis that extends in a direction orthogonal to the traveling direction of the intermediate transfer belt 7. An electrostatic latent image is formed on the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d.

  Each of the charging units 10a, 10b, 10c, and 10d is disposed to face the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d. Each of the charging units 10a, 10b, 10c, and 10d uniformly charges the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d negatively (minus polarity) or positively (plus polarity).

  The laser scanner units 4a, 4b, 4c, and 4d function as exposure units, and are spaced apart from the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d. Each of the laser scanner units 4a, 4b, 4c, and 4d includes a laser light source (not shown), a polygon mirror, a polygon mirror driving motor, and the like.

  Each of the laser scanner units 4a, 4b, 4c, and 4d scans and exposes the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d based on image information related to the image read by the reading unit 301. Scanning exposure is performed by each of the laser scanner units 4a, 4b, 4c, and 4d, so that charges charged on the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d are removed. Thereby, electrostatic latent images are formed on the respective surfaces of the photosensitive drums 2a, 2b, 2c, and 2d.

  The developing devices 16a, 16b, 16c, and 16d are provided corresponding to the photosensitive drums 2a, 2b, 2c, and 2d, respectively, and are disposed to face the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d. Each of the developing devices 16a, 16b, 16c, and 16d develops a color toner image by attaching toner of each color to the electrostatic latent images formed on the photosensitive drums 2a, 2b, 2c, and 2d (photosensitive drums). A toner image is formed on the surface). Each of the developing devices 16a, 16b, 16c, and 16d corresponds to four toner colors of yellow, cyan, magenta, and black. Each of the developing devices 16a, 16b, 16c, and 16d includes a developing roller that can be disposed opposite to the surface of the photosensitive drums 2a, 2b, 2c, and 2d, a stirring roller for stirring toner, and the like.

  Each of the toner cartridges 5a, 5b, 5c, and 5d is provided corresponding to each of the developing devices 16a, 16b, 16c, and 16d, and each color toner supplied to each of the developing devices 16a, 16b, 16c, and 16d. To accommodate. Each of the toner cartridges 5a, 5b, 5c, and 5d accommodates yellow toner, cyan toner, magenta toner, and black toner.

  The toner supply units 6a, 6b, 6c, and 6d are provided corresponding to the toner cartridges 5a, 5b, 5c, and 5d and the developing devices 16a, 16b, 16c, and 16d, respectively. The toners of the respective colors accommodated in 5d are supplied to the developing devices 16a, 16b, 16c, and 16d, respectively.

  The toner images of the respective colors developed on the photosensitive drums 2a, 2b, 2c, and 2d are sequentially transferred to the intermediate transfer belt 7. The intermediate transfer belt 7 is stretched around a driven roller 35, a counter roller 18 including a driving roller, a tension roller 36, and the like. Since the tension roller 36 biases the intermediate transfer belt 7 from the inside to the outside, a predetermined tension is applied to the intermediate transfer belt 7.

  Primary transfer rollers 37a, 37b, 37c, and 37d are arranged to face each other on the side opposite to the photosensitive drums 2a, 2b, 2c, and 2d with the intermediate transfer belt 7 interposed therebetween.

  A predetermined portion of the intermediate transfer belt 7 is sandwiched between the primary transfer rollers 37a, 37b, 37c, and 37d and the photosensitive drums 2a, 2b, 2c, and 2d, respectively. The predetermined portion thus sandwiched is pressed against the surface of each of the photosensitive drums 2a, 2b, 2c, and 2d. Primary transfer nips N1a, N1b, N1c, and N1d are formed between the photosensitive drums 2a, 2b, 2c, and 2d and the primary transfer rollers 37a, 37b, 37c, and 37d, respectively. In the primary transfer nips N1a, N1b, N1c, and N1d, the respective color toner images developed on the photosensitive drums 2a, 2b, 2c, and 2d are sequentially transferred to the intermediate transfer belt 7. As a result, a full-color toner image is formed on the intermediate transfer belt 7.

  The primary transfer rollers 37a, 37b, 37c, and 37d are respectively transferred to the intermediate transfer belt 7 with the respective color toner images developed on the photosensitive drums 2a, 2b, 2c, and 2d by a voltage application unit (not shown). The primary transfer bias is applied.

  The static eliminators 12a, 12b, 12c, and 12d are arranged to face the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, respectively. The static eliminators 12a, 12b, 12c, and 12d respectively irradiate the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d to irradiate light, and the photosensitive drums 2a, 2b, and 2c after the primary transfer is performed. 2d, each surface is neutralized (charge is removed).

  The drum cleaning units 11a, 11b, 11c, and 11d are disposed to face the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, respectively. Each of the drum cleaning units 11a, 11b, 11c, and 11d removes toner and adhering matter remaining on the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d, and conveys the removed toner to a predetermined recovery mechanism. And collect.

  The secondary transfer roller 8 secondarily transfers the toner image primarily transferred to the intermediate transfer belt 7 onto the paper T. A secondary transfer bias for transferring the toner image formed on the intermediate transfer belt 7 to the paper T is applied to the secondary transfer roller 8 by a voltage application unit (not shown).

  The secondary transfer roller 8 is brought into contact with and separated from the intermediate transfer belt 7. Specifically, the secondary transfer roller 8 is configured to be movable between a contact position where the secondary transfer roller 8 is in contact with the intermediate transfer belt 7 and a spaced position where the secondary transfer roller 8 is separated from the intermediate transfer belt 7. Specifically, the secondary transfer roller 8 is moved to the contact position when the toner image primarily transferred onto the surface of the intermediate transfer belt 7 is secondarily transferred to the paper T, and is separated from the other position. Moved to.

  A counter roller 18 is disposed on the side of the intermediate transfer belt 7 that faces the secondary transfer roller 8. A predetermined portion of the intermediate transfer belt 7 is sandwiched between the secondary transfer roller 8 and the opposing roller 18. Then, the paper T is pressed against the outer surface of the intermediate transfer belt 7 (the surface on which the toner image is primarily transferred). A secondary transfer nip N <b> 2 is formed between the secondary transfer roller 8 and the opposing roller 18. The toner image primarily transferred to the intermediate transfer belt 7 is secondarily transferred to the paper T in the secondary transfer nip N2.

  The fixing unit 9 melts and fixes each color toner constituting the toner image secondarily transferred to the paper T to the paper T. The fixing unit 9 includes a heating roller 9a heated by a heater and a pressure roller 9b pressed against the heating roller 9a. The heating roller 9a and the pressure roller 9b convey the paper T onto which the toner image is secondarily transferred so as to sandwich the paper T. When the paper T is conveyed so as to be sandwiched between the heating roller 9a and the pressure roller 9b, the toner transferred onto the paper T is melted and fixed on the paper T.

Next, the paper supply / discharge unit will be described.
As shown in FIG. 1, in the lower part of the apparatus main body M, two paper feed cassettes 52 that store paper T are arranged in an up-down direction. The paper feed cassette 52 is configured to be pulled out from the housing of the apparatus main body M in the horizontal direction. In the paper feed cassette 52, a placement plate 60 on which the paper T is placed is disposed. In the paper feed cassette 52, the paper T is stored in a state of being stacked on the placement plate 60. The paper T placed on the placement plate 60 is sent out to the transport path L by the cassette paper feed unit 51 arranged at the end of the paper feed cassette 52 on the paper feed side (the left end in FIG. 1). The cassette paper feed unit 51 includes a double feed prevention mechanism including a forward feed roller 61 for taking out the paper T on the placement plate 60 and a paper feed roller pair 63 for feeding the paper T to the transport path L one by one. Prepare.

  A manual paper feed unit 64 is provided on the right side surface (right side in FIG. 1) of the apparatus main body M. The manual paper feed unit 64 is provided mainly for supplying the apparatus main body M with a paper T of a size and type different from the paper T set in the paper feed cassette 52. The manual paper feed unit 64 includes a manual feed tray 65 that forms a part of the apparatus main body M in the closed state, and a paper feed roller 66. The lower end of the manual feed tray 65 is attached to the vicinity of the paper feed roller 66 so as to be rotatable (openable and closable). The paper T is placed on the open manual feed tray 65. The manual paper feed unit 64 feeds the paper T placed on the open manual feed tray 65 to the manual feed path La.

  A first paper discharge unit 50 a and a second paper discharge unit 50 b are provided on the upper side of the apparatus main body M. The first paper discharge unit 50a and the second paper discharge unit 50b discharge the paper T to the outside of the apparatus main body M. Details of the first paper discharge unit 50a and the second paper discharge unit 50b will be described later.

  The conveyance path L for conveying the paper T includes a first conveyance path L1 from the cassette paper feeding unit 51 to the secondary transfer roller 8, a second conveyance path L2 from the secondary transfer roller 8 to the fixing unit 9, and a fixing unit. 9 to the first paper discharge section 50a, the manual conveyance path La for joining the paper supplied from the manual paper feed section 64 to the first conveyance path L1, and the third conveyance path L3 on the upstream side. The paper transported from the upstream side to the downstream side is reversed and returned to the first transport path L1, and the paper transported from the upstream side to the downstream side of the third transport path L3 is sent to the post-processing device (not shown). And a post-processing conveyance path Lc for conveyance.

Moreover, the 1st junction part P1 and the 2nd junction part P2 are provided in the middle of the 1st conveyance path L1. A first branch portion Q1 is provided in the middle of the third transport path L3.
The first joining part P1 is a joining part where the manual feed path La joins the first transport path L1. The second junction P2 is a junction where the return conveyance path Lb merges with the first conveyance path L1.
The first branch portion Q1 is a branch portion where the post-processing transport path Lc branches from the third transport path L3. A rectifying member 58 is provided in the first branch portion Q1. The rectifying member 58 rectifies the transport direction of the paper T carried out from the fixing unit 9 to the third transport path L3 toward the first paper discharge section 50a or the post-processing transport path Lc toward the second paper discharge section 50b ( Switch).

  In the middle of the first transport path L1 (specifically, between the second joining portion P2 and the secondary transfer roller 8), a sensor for detecting the paper T and correction of the skew (oblique paper feeding) of the paper T In addition, a registration roller pair 80 for adjusting the timing with the toner image is disposed. The sensor is disposed immediately before (on the upstream side) the registration roller pair 80 in the transport direction of the paper T. The registration roller pair 80 conveys the paper T by performing the above-described correction and timing adjustment based on the detection signal information from the sensor.

  The return conveyance path Lb is a conveyance path that is provided so that the opposite surface (non-printing surface) to the surface that has already been printed faces the photosensitive drum 2 when performing duplex printing on the paper T. According to the return transport path Lb, the paper T transported from the first branching section Q1 to the paper discharge section 50 is turned upside down and returned to the first transport path L1 and arranged upstream of the secondary transfer roller 8. It can be conveyed to the upstream side of the pair of registration rollers 80. A predetermined toner image is transferred onto the non-printing surface by the photosensitive drum 2 on the paper T that has been turned upside down by the return conveyance path Lb.

  A first paper discharge unit 50a is formed at the end of the third transport path L3. The first paper discharge unit 50 a is disposed on the upper side of the apparatus main body M. The first paper discharge unit 50a is open toward the right side surface of the apparatus main body M (the right side in FIG. 1, the manual paper feed unit 64 side). The first paper discharge unit 50a discharges the paper T transported through the third transport path L3 to the outside of the apparatus main body M.

  On the opening side of the first paper discharge section 50a, a paper discharge stacking section M1 is formed. The paper discharge stacking unit M1 is formed on the upper surface (outer surface) of the apparatus main body M. The paper discharge stacking unit M1 is a part formed by the upper surface of the apparatus main body M being depressed downward. The bottom surface of the paper discharge stacking unit M1 constitutes part of the top surface of the apparatus main body M. In the paper discharge stacking unit M1, sheets T onto which a predetermined toner image is transferred and discharged from the first paper discharge unit 50a are stacked and stacked.

A second paper discharge unit 50b is formed at the end of the post-processing conveyance path Lc. The second paper discharge unit 50b is disposed on the upper side of the apparatus main body M. The second paper discharge section 50b opens toward the left side of the apparatus main body M (left side in FIG. 1, the side to which the post-processing apparatus is connected). The second paper discharge unit 50b discharges the paper T conveyed through the post-processing conveyance path Lc to the outside of the apparatus main body M.
A post-processing device (not shown) is connected to the opening side of the second paper discharge unit 50b. The post-processing device performs post-processing (stapling, punching, etc.) of paper ejected from the image forming apparatus (copy machine 1).
A paper detection sensor is disposed at a predetermined position on each conveyance path.

Next, a paper jam (JAM) in the main transport path L1 to L3 (the first transport path L1, the second transport path L2, and the third transport path L3 are collectively referred to as “main transport path” hereinafter) and the return transport path Lb. A structure for eliminating the problem will be briefly described.
As shown in FIG. 1, on the left side surface (left side in FIG. 1) of the apparatus main body M, main conveyance paths L1 to L3 and a return conveyance path Lb are arranged in parallel so as to mainly extend in the vertical direction. A cover body 40 is provided on the left side of the apparatus body M (left side in FIG. 1) so as to form a part of the side surface of the apparatus body M. The cover body 40 is connected to the apparatus main body M via a fulcrum shaft 43 at the lower end thereof. The fulcrum shaft 43 is disposed along the direction in which the axial direction crosses the main transport paths L1 to L3 and the return transport path Lb. The cover body 40 is configured to be rotatable between a closed position (position shown in FIG. 1) and an open position (not shown) with the fulcrum shaft 43 as a center.

  The cover body 40 includes a first cover portion 41 that is rotatably connected to the apparatus main body M by a fulcrum shaft 43, and a second cover portion 42 that is rotatably connected to the apparatus main body M by the same fulcrum shaft 43. It consists of and. The first cover portion 41 is located on the outer side (side surface side) of the apparatus main body M than the second cover portion 42. In FIG. 1, the hatched portion with the left-down dashed line is the first cover portion 41, and the hatched portion with the right-down dashed line is the second cover portion 42.

In the state where the cover body 40 is located at the closed position, the outer surface side of the first cover portion 41 forms a part of the outer surface (side surface) of the apparatus main body M.
Further, in the state where the cover body 40 is located at the closed position, the inner surface side (the apparatus main body M side) of the second cover portion 42 forms a part of the main transport paths L1 to L3.
Further, in a state where the cover body 40 is located at the closed position, the inner surface side of the first cover portion 41 and the outer surface side of the second cover portion 42 form at least a part of the return conveyance path Lb. That is, the return conveyance path Lb is formed between the first cover part 41 and the second cover part 42.

  The copying machine 1 of the present embodiment includes the cover body 40 having such a configuration, so that when a paper jam (JAM) occurs in the main transport paths L1 to L3, the cover body 40 is closed as shown in FIG. By rotating from the position to an open position (not shown) to open the main transport paths L1 to L3, it is possible to process paper jammed in the main transport paths L1 to L3. On the other hand, when a paper jam occurs in the return conveyance path Lb, the cover body 40 is rotated to the open position, and then the second cover portion 42 is moved to the apparatus main body M side (right side in FIG. ) To open the return conveyance path Lb, the paper jammed in the return conveyance path Lb can be processed.

Next, the reading unit 301 constituting the image reading apparatus 300 will be described with reference to FIGS. 2 to 6B.
FIG. 2 is a schematic plan view showing the internal structure of the reading unit 301 of the image reading apparatus 300. FIG. 3 is a view of the image reading apparatus 300 shown in FIG. 4 is a partially enlarged view of the light guide 505 shown in FIG. FIG. 5 is a perspective view of the LED unit 503 shown in FIG. FIG. 6A is a diagram illustrating a case where the light guide 505 is disposed so that the light incident portion 400 faces the plurality of LEDs 501 and the light exit portion 410 faces the document G. FIG. 6B is a diagram illustrating a light amount distribution in the main scanning direction Y when no light guide is disposed.

  2 and 3, the reading unit 301 includes a contact glass 335 on which the document G is placed, a pair of guide rails 345, a drive shaft 350 to which a drive pulley 351 is attached, and a driven pulley 352. An attached support shaft 353, an illumination unit 347 as illumination means, a mirror unit 349, an imaging lens 357, a CCD 358 as reading means, and an optical sensor 362 are provided.

  As illustrated in FIG. 2, the reading unit 301 includes a contact glass 335 that is disposed on the upper surface (front side in FIG. 2) and on which the document G is placed. The contact glass 335 is disposed substantially parallel to the horizontal plane when the copier 1 is disposed in a normal state.

  As shown in FIG. 2, the pair of guide rails 345 are disposed between the side surfaces 306 a and 306 b (left and right in FIG. 2) of the reading unit 301. The pair of guide rails 345 are installed in parallel with the above-described contact glass 335 (see FIG. 3). An illumination unit 347 and a mirror unit 349 are movably mounted on the pair of guide rails 345.

  As shown in FIG. 2, the drive shaft 350 is disposed on the side surface 306 a side so as to be orthogonal to the guide rail 345. The drive shaft 350 is driven forward or reversely by a drive motor (not shown). A drive pulley 351 having a large diameter portion and a small diameter portion is attached to both ends of the drive shaft 350 and outside the guide rail 345 in the main scanning direction Y.

  As shown in FIG. 2, the support shaft 353 is disposed on the side surface 306 b side so as to be orthogonal to the guide rail 345. A driven pulley 352 having the same diameter as the drive pulley 351 is attached to both ends of the support shaft 353 and outside the guide rail 345 in the main scanning direction Y.

A driving wire 354 a is stretched over the large diameter portions of the driving pulley 351 and the driven pulley 352. The lighting unit 347 is fixed to the driving wire 354a.
A drive wire 354 b is stretched over the small diameter portions of the drive pulley 351 and the driven pulley 352. The mirror unit 349 is fixed to the drive wire 354b.

  As the drive shaft 350 is rotated by the drive motor, the drive wires 354a and 354b are rotated. By rotating the drive wires 354a and 354b, the illumination unit 347 and the mirror unit 349 are moved along the guide rail 345 in the sub-scanning direction X (the left-right direction in FIGS. 2 and 3). The diameter ratio between the large diameter portion and the small diameter portion in the drive pulley 351 and the driven pulley 352 is 2: 1. Therefore, the ratio of the moving distance between the illumination unit 347 and the mirror unit 349 is 2: 1.

  In the present embodiment, a configuration in which the ratio of the moving distance between the illumination unit 347 and the mirror unit 349 is 2: 1 is realized by using the driving pulley 351 and the driven pulley 352 having the large diameter portion and the small diameter portion. However, it is not limited to this. For example, by providing a moving pulley on the mirror unit 349 and fixing the lighting unit 347 to a driving wire or the like, the ratio of the moving distance between the lighting unit 347 and the mirror unit 349 can be increased using the principle of the moving pulley. A configuration of 2: 1 can also be realized.

  Here, two contacts 355 are provided at portions of the illumination unit 347 and the mirror unit 349 that are in contact with the upper surface of the guide rail 345. The contact surface of each contact 355 with the guide rail 345 is spherical. Thereby, the illumination unit 347 and the mirror unit 349 are smoothly moved in the sub-scanning direction X.

  As shown in FIG. 2, an ISU base 356 that is a member that supports the imaging lens 357, the CCD 358, and the like is attached to the side surface 306a side of the bottom surface of the reading unit 301. An imaging lens 357 and a CCD 358 as a reading unit are attached to the upper surface of the ISU base 356 in a predetermined positional relationship.

  As shown in FIG. 2, the imaging lens 357 is installed on a lens support 359 that is fixed to the ISU base 356. The lens support base 359 is disposed such that its position can be adjusted by a guide member 360 disposed on the CCD 358 side. The imaging lens 357 is disposed at the approximate center in the sub-scanning direction X of the reading unit 301. The imaging lens 357 is disposed on the end side opposite to the original G side in the optical path H (see FIG. 3). The imaging lens 357 forms an image of the incident light beam H4 (see FIG. 3) at a predetermined position. That is, the imaging lens 357 forms an image of the original G at a predetermined position.

  As shown in FIG. 2, the CCD 358 is mounted on a CCD substrate 361 disposed on the back surface of the guide member 360. The CCD 358 is disposed at an image forming position in the image forming lens 357. The light beam from the imaging lens 357 is incident on the CCD 358 through the opening window 360 a formed near the center of the guide member 360. The optical axis of the light beam incident on the CCD 358 is corrected by finely adjusting the position of the guide member 360.

  The optical sensor 362 is disposed on the ISU base 356. The optical sensor 362 detects the size of the document (left and right direction in FIG. 2) depending on whether or not the reflected light from the document G placed on the contact glass 335 is received.

  As illustrated in FIG. 3, the illumination unit 347 includes an illumination unit 340 as a light emitting unit, a first mirror 321, and a first frame body 311 that houses the illumination unit 340 and the first mirror 321.

  The illumination unit 340 includes an LED unit 503 to which a plurality of LEDs 501 as light emitting units are attached, and a light guide body 505 that is disposed in proximity to or in contact with the plurality of LEDs 501. The illumination unit 340 will be described in detail later.

  The first mirror 321 is disposed on the lower side in the thickness direction Z of the illumination unit 347. The first mirror 321 is arranged so that the reflection surface faces the document G and the second mirror 322 side. The first mirror 321 reflects the light beam H 1 from the document to the second mirror 322.

  The first frame body 311 is fixed to a drive wire 354a (see FIG. 2) that spans over the large diameter portions of the drive pulley 351 and the driven pulley 352 (see FIG. 2). The first frame 311 is moved in the sub-scanning direction X along the guide rail 345 by rotating the driving wires 354a and 354b.

  As shown in FIG. 3, the mirror unit 349 includes a second mirror 322, a third mirror 323, and a second frame 312 that accommodates the second mirror 322 and the third mirror 323.

  The second mirror 322 is disposed on the upper side in the thickness direction Z of the second frame 312. The second mirror 322 is arranged so that the reflection surface faces the first mirror 321 and the third mirror 323 side. The second mirror 322 reflects the light beam H2 from the first mirror 321 to the third mirror 323 side.

  The third mirror 323 is disposed on the lower side in the thickness direction Z of the second frame 312. The third mirror 323 is arranged so that the reflection surface faces the second mirror 322 and the imaging lens 357 side. The third mirror 323 reflects the light beam H3 from the second mirror 322 to the imaging lens 357 side.

Here, the illumination unit 340 will be described in detail with reference to FIGS.
As shown in FIG. 4, the illumination unit 340 includes an LED unit 503 to which a plurality of LEDs 501 are attached, and a light guide 505.

  As shown in FIG. 4, each of the plurality of LEDs 501 is attached to a plate-like member 502 (see FIG. 3) so as to be separated from each other. Each of the plurality of LEDs 501 is arranged at regular intervals in the main scanning direction Y so that the light emitting surface faces the document side. Each of the plurality of LEDs 501 is attached to an attachment member 510 (see FIG. 3). Each of the plurality of LEDs 501 emits light applied to the document G.

  As shown in FIG. 4, the light guide 505 is disposed such that one end 505a faces the LED unit 503 side where the plurality of LEDs 501 are disposed, and the other end 505b faces the contact glass 335 side. The light guide 505 has a light incident part 400 formed on the one end 505a side and a light exit part 410 formed on the other end 505b side.

  The light entrance unit 400 is disposed to face the plurality of LEDs 501. Light from the plurality of LEDs 501 enters the light incident portion 400 toward the inside of the light guide 505. The light exit unit 410 is disposed to face the document G. The light exit unit 410 emits the light incident on the light entrance unit 400 toward the document G side.

  As shown in FIG. 4, the light guide 505 of the first embodiment has a hollow portion 506 that is formed so as to connect the light entrance portion 400 and the light exit portion 410. The light guide 505 is a hollow light guide. The light incident portion 400 is a rectangular opening that is long in the main scanning direction Y. The light incident part 400 (opening part) is disposed to face the plurality of LEDs 501. The light exit portion 410 is a rectangular opening that is long in the main scanning direction Y. The light exit portion 410 (opening portion) is disposed to face the original G.

  The light guide 505 is a light guide plate portion that is long in the main scanning direction Y, and connects the two main light guide plate portions 507a and 507a that are disposed to face each other, and the end portions of the main light guide plate portion 507a. It has two sub light guide plate portions 507b and 507b arranged to face each other. The main light guide plate portion 507a has a substantially rectangular shape that is long in the main scanning direction Y. The light guide 505 is configured as a hollow frame having an opening as the light entrance 400 and an opening as the light exit 410.

  The hollow portion 506 is formed by the inner surfaces of the four light guide plate portions 507a, 507a, 507b, and 507b. The light guide 505 has a light reflecting surface formed on the inner surfaces of the four light guide plate portions 507a, 507a, 507b, and 507b constituting the hollow portion 506. For example, the light reflection surface is configured by providing a metal reflection film on the inner surfaces of four light guide plate portions 507a, 507a, 507b, and 507b.

  The inner surfaces (light reflecting surfaces) of the light guide plate portions 507a and 507b have a predetermined light reflectance. The light beam incident from the light incident part 400 side of the light guide 505 travels straight while light diffusion is suppressed by the light guide plate parts 507a and 507b. A part of the light beam incident from the light incident part 400 side is emitted from the light output part 410 side as a uniform light beam as a whole while being reflected and collected by the inner surfaces of the light guide plate parts 507a and 507b.

  The light guide 505 includes a first light guide 508 located on the end side in the main scanning direction Y and a second light guide 509 located in the center in the main scanning direction Y. The light guide 505 has a distance between the light incident part 400 and the light output part 410 in the first light guide part 508 and a distance between the light incident part 400 and the light output part 410 in the second light guide part 509. Configured differently.

  Specifically, as shown in FIG. 4, the main light plate portion 507 a of the first embodiment has a concave shape in which the end portion on the light incident portion 400 side is recessed toward the light exit portion 410 side in the central portion in the main scanning direction Y. It is formed. The main light guide plate portion 507a is formed in a concave shape in which the depression distance gradually increases from the end in the main scanning direction Y toward the center.

  The inner surfaces of the four light guide plate portions 507a, 507a, 507b, and 507b constituting the hollow portion 506 have a first light reflecting portion 600 having a predetermined light reflectance. The first light reflection unit 600 includes a first part 601 corresponding to the first light guide part 508 and a second part 602 corresponding to the second light guide part 509.

  In the first light reflecting unit 600, the distance between the light entering unit 400 and the light emitting unit 410 in the second part 602 is shorter than the distance between the light entering unit 400 and the light emitting unit 410 in the first part 601. Formed as follows. Specifically, as described above, the light guide 505 is formed in a concave shape in which the light incident portion 400 is recessed in the center portion in the main scanning direction Y. For this reason, the light incident portion 400 of the light guide 505 is disposed in the center portion in the main scanning direction Y so as to be separated from the plurality of LEDs 501 serving as light emitting portions. Further, the light incident portion 400 of the light guide 505 increases in distance from the plurality of LEDs 501 as it approaches the central portion in the main scanning direction Y.

Next, the operation of the image reading apparatus 300 according to this embodiment will be described.
First, the lid member 70 (see FIG. 1) is opened, and the document G is placed on the reading surface 302A (see FIG. 3). When the optical sensor 362 (see FIG. 3) detects that a document is placed on the reading surface 302A, the illumination unit 347 and the mirror unit 349 (see FIG. 3) are connected to the side surface 306a of the internal space 304 (see FIG. 3). 3).

  Next, the lid member 70 is closed. Then, by pressing a start switch (not shown), the copying machine 1 is instructed to duplicate the image of the original G. By pressing the start switch, the image reading apparatus 300 starts reading an image of the original G.

  Specifically, first, a plurality of LEDs 501 (see FIG. 3) are turned on. Light from the plurality of LEDs 501 that have been lit is incident on the inside of the light guide 505 from the light incident part 400. In this case, in the central portion of the light incident portion 400 in the main scanning direction Y, the light incident portion 400 is separated from the plurality of LEDs 501, so that part of the light is diffused and is not incident on the light incident portion 400. Further, on the end side in the main scanning direction Y of the light incident part 400, the distance from the plurality of LEDs 501 is smaller than the central part, so that more light than the light incident at the central part is incident on the light incident part 400. Is incident. Therefore, the amount of light incident from the light incident portion 400 in the central portion in the main scanning direction Y is small, and the amount of light incident from the light incident portion 400 on the end side in the main scanning direction Y is large.

  The light incident from the light incident part 400 is emitted from the light exit part 410 while being condensed as a whole. The light quantity distribution of the light H01 emitted from the light exit part 410 has a small light quantity at the center in the main scanning direction Y and a large quantity of light at the end side, similarly to the light quantity distribution of the light quantity incident from the light incident part 400. (See FIG. 6A). The light H01 emitted from the light exit unit 410 is directed toward the original G and is directly irradiated onto the original G. The original G is irradiated with line-shaped light extending in the main scanning direction Y. Accordingly, the amount of light irradiated on the surface of the original G can be increased in the main scanning direction Y because the amount of light on the edge side in the main scanning direction Y can be larger than the amount of light in the central portion. A light amount distribution can be obtained.

  Each of the illumination unit 347 and the mirror unit 349 is moved in the sub-scanning direction X while the original G is irradiated with light. Each of the illumination unit 347 and the mirror unit 349 moves while keeping the optical path length in the optical path H constant.

  The light beam from the original G is reflected by the first mirror 321, the second mirror 322, and the third mirror 323, and then enters the imaging lens 357 (see FIG. 3).

  The imaging lens 357 forms an image of the original G. In general, the amount of light that has passed through the imaging lens 357 decreases on the end side due to the lens characteristics of the imaging lens 357. In the present embodiment, the amount of light incident on the imaging lens 357 is larger on the end side than on the center in the main scanning direction Y. Therefore, the variation between the end portion side and the central portion is reduced by the reduction of the light amount on the end portion side of the light passing through the imaging lens 357. In this way, variation in the amount of light is suppressed. The CCD 358 arranged at the image formation position reads the image of the original G as image information based on the image formed on the CCD 358 after passing through the opening window 360a of the guide member 360 (see FIG. 3).

  Image information read by the CCD 358 is output to the CCD substrate 361. The image information output to the CCD substrate 361 is output to the apparatus main body M via a predetermined circuit board (see FIG. 3).

  In the apparatus main body M, the input image information is input to an image formation control unit (not shown). The image formation control unit controls the photosensitive drum 2 as an image carrier constituting the image formation unit, the charging units 10a to 10d, the laser scanner units 4a to 4d, the developing devices 16a to 16d, and the like based on the image information. . A predetermined toner image is formed on the photosensitive drum 2 based on the image information (see FIG. 1).

  The same image as the image of the original G is transferred to the paper T conveyed to the primary transfer nips N1a, N1b, N1c, and N1d formed by the photosensitive drum 2 via the conveyance path L based on the image information. . The paper T on which the image is formed is discharged from the first paper discharge unit 50a and the second paper discharge unit 50b to the outside of the apparatus main body M (see FIG. 1).

  According to the present embodiment, the light guide 505 includes the distance between the light entrance 400 and the light exit 410 in the first light guide 508 and the distance between the light entrance 400 and the light exit 410 in the second light guide 509. The distance is configured to be different. In addition, the distance between the light entering part 400 and the light exiting part 410 in the first part 601 of the first light reflecting part 600 and the distance between the light entering part 400 and the light exiting part 410 in the second part 602 are different. Configured as follows. Accordingly, the amount of light radiated on the surface of the original G can be less than the amount of light at the central portion in the main scanning direction Y. Therefore, it is possible to suppress variations in the amount of light due to a decrease in the amount of light at the end of the image read by the imaging lens 357. Then, unevenness in the amount of light entering the CCD 358 can be suppressed. As a result, luminance unevenness (brightness unevenness) in an image read by the CCD 358 can be suppressed.

  Further, according to the present embodiment, the light guide 505 is formed in a concave shape in which the light incident portion 400 is recessed toward the light exit portion 410 at the center portion in the main scanning direction Y. Accordingly, since the amount of light on the end side in the main scanning direction Y can be increased compared to the central portion, a good light amount distribution in the main scanning direction Y can be obtained. Then, unevenness in the amount of light entering the CCD 358 can be suppressed. As a result, luminance unevenness (brightness unevenness) in an image read by the CCD 358 can be suppressed.

  Further, according to the present embodiment, the light guide 505 has a good light quantity distribution in the main scanning direction Y only by making the light incident part 400 recessed in the central part in the main scanning direction Y and recessed in the light exiting part 410 side. Can be obtained. According to the light guide 505 of the present embodiment, it is possible to obtain an image reading apparatus (image forming apparatus) that suppresses unevenness in the amount of light entering the CCD 358 while suppressing costs.

A specific example of the light amount distribution in the main scanning direction Y will be described as shown in FIGS. 6A and 6B.
According to the present embodiment, as shown in FIG. 6A, the amount of light on the end side in the main scanning direction Y can be increased as compared with the central portion, so that a good light amount distribution in the main scanning direction Y can be obtained. it can. On the other hand, as shown in FIG. 6B, when the light guide is not arranged, the light amount distribution in the main scanning direction Y is smaller in the main scanning direction Y than the center portion. A good light quantity distribution cannot be obtained in the main scanning direction Y.
As shown in FIG. 6A, by increasing the light amount distribution in the main scanning direction Y on the end side compared to the center portion, variation in the light amount due to the decrease in the light amount at the end portion in the image read by the imaging lens 357 is suppressed. .

  Next, the copier according to the second embodiment will be described with reference to FIG. FIG. 7 is a partially enlarged view showing the light guide 505A. The copying machine according to the second embodiment is the same except that the light exiting portion 410 of the light guide 505 is recessed to the light entering portion 400 side and the light entering portion 400 is not recessed to the light exiting portion 410 side. The configuration is the same as that of the copier 1 in the embodiment.

  As shown in FIG. 7, in the second embodiment, the leading light plate portion 507a of the light guide 505A has a shape in which the end portion on the light exiting portion 410 side is recessed toward the light incident portion 400 side in the central portion in the main scanning direction Y. It is. The main light guide plate portion 507a is configured to have a shape in which the depression distance gradually decreases from the central portion in the main scanning direction Y toward the end portion.

Next, the operation of the copier in this embodiment will be described.
According to the present embodiment, the light guide 505A is formed in a concave shape in which the light exiting portion 410 is recessed toward the light incident portion 400 in the central portion in the main scanning direction Y. The amount of light incident from the light incident portion 400 decreases on the light exit portion 410 side. Accordingly, the amount of light on the end side in the main scanning direction Y can be increased as compared with the central portion, so that the light amount distribution on the original G surface of the light H01 in the main scanning direction Y can be adjusted favorably.

  According to this embodiment, the same effect as that of the first embodiment can be obtained.

  Next, the copier according to the third embodiment will be described with reference to FIG. FIG. 8 is a partially enlarged view showing the light guide 505B. Here, the copier in the third embodiment has the same configuration as the copier 1 in the first embodiment except for the light guide 505B. Hereinafter, only the light guide 505B different from the copier 1 in the first embodiment will be described, and description of other components will be omitted.

  As shown in FIG. 8, the light guide body 505 </ b> B has a hollow portion 506 that is formed so as to connect the light entrance portion 400 and the light exit portion 410. The light guide 505B is a hollow light guide. The light guide 505B is different from the first embodiment in that the distance between the light incident part 400 and the light output part 410 is substantially uniform in the main scanning direction Y in the main scanning direction Y. In other words, the light guide 505B is not configured in a concave shape in which the light incident part 400 is recessed toward the light output part 410.

  The light guide 505B includes a second light reflecting portion 603 having a light reflectance lower than that of the first light reflecting portion 600. The second light reflecting portion 603 is disposed on the inner surface of the hollow portion 506 on the light incident portion 400 side of the second portion 602 of the first light reflecting portion 600. The first light reflecting unit 600 is configured such that the distance between the light entering part 400 and the light exiting part 410 in the second part 602 is shorter than the distance between the light entering part 400 and the light exiting part 410 in the first part 601. Placed in. The first light reflecting portion 600 is arranged such that the distance between the light incident portion 400 and the light exiting portion 410 in the second portion 602 is short, and the distance gradually increases toward the second portion 602. That is, the second light reflecting portion 603 has a shape in which the area is large at the center portion in the main scanning direction Y and the area gradually decreases toward the end side.

  For example, on the inner surface of the hollow portion 506, the portion formed by pasting black or gray paint or a black or gray sheet is the second light reflecting portion 603, and other black or gray paint or black or gray The portion where the sheet is not attached is the first light reflecting portion 600.

Next, the operation of the copier in this embodiment will be described.
According to the present embodiment, since the light reflectance of the second part 602 is lower than the light reflectance of the first part 601, the amount of light incident from the light incident part 400 at the central part in the main scanning direction Y is In the light output part 410 side, it decreases. Accordingly, the amount of light on the end side in the main scanning direction Y can be increased as compared with the central portion, so that the light amount distribution on the original G surface of the light H01 in the main scanning direction Y can be adjusted favorably.

  According to this embodiment, the same effect as that of the first embodiment can be obtained.

  Next, the copier according to the fourth embodiment will be described with reference to FIG. FIG. 9 is a partially enlarged view showing the light guide 505C. The copier in the fourth embodiment has the same configuration as that of the copier 1 in the third embodiment except for the position where the second light reflection unit 603 is disposed.

  As illustrated in FIG. 9, the second light reflecting unit 603 of the fourth embodiment is disposed on the light output unit 410 side in the first light reflecting unit 600. The first light reflecting unit 600 is configured such that the distance between the light entering part 400 and the light exiting part 410 in the second part 602 is shorter than the distance between the light entering part 400 and the light exiting part 410 in the first part 601. Placed in. The first light reflecting portion 600 is arranged such that the distance between the light incident portion 400 and the light exiting portion 410 in the second portion 602 is short, and the distance gradually increases toward the second portion 602. That is, the second light reflecting portion 603 has a shape in which the area is large at the center portion in the main scanning direction Y and the area gradually decreases toward the end side.

Next, the operation of the copier in this embodiment will be described.
According to the present embodiment, since the second light reflecting unit 603 is disposed on the light exiting unit 410 side in the first light reflecting unit 600, the amount of light received from the light entering unit 400 at the center in the main scanning direction Y. Decreases on the light output part 410 side. Therefore, the amount of light on the end side in the main scanning direction Y can be increased as compared with the central portion, so that a good light amount distribution in the main scanning direction Y can be obtained.

  According to this embodiment, the same effect as that of the third embodiment can be obtained.

  Next, the copier according to the fifth embodiment will be described with reference to FIG. FIG. 10 is a partially enlarged view illustrating a light guide body 505D having a light-transmitting member and formed in a solid shape. Here, the copier in the fifth embodiment has the same configuration as that of the copier 1 in the first embodiment except that the light guide 505D is formed of a light transmissive member in a solid shape. Hereinafter, only the light guide 505D different from the copier 1 in the first embodiment will be described, and description of other components will be omitted.

  As shown in FIG. 10, the light guide 505 </ b> D of the fifth embodiment is a solid light guide having a light-transmitting member formed so as to connect the light incident part 400 and the light output part 410. The light guide 505D has a substantially rectangular parallelepiped shape that is long in the main scanning direction Y. The light incident portion 400 is a rectangular light incident surface that is long in the main scanning direction Y. The light incident part 400 (light incident surface) is disposed to face the plurality of LEDs 501. The light exit portion 410 is a rectangular light exit surface that is long in the main scanning direction Y. The light exit unit 410 (light exit surface) is disposed to face the original G.

  For example, the light guide 505D is configured in a block shape by disposing a member having high light reflectivity around an acrylic resin having light transmittance. Examples of the member disposed around the light-transmitting acrylic resin include a milky white resin and a metal reflection film.

  The inner surface (light reflecting surface) of the light guide 505D has a predetermined light reflectance. The light beam incident from the light incident portion 400 side of the light guide 505 travels straight while light diffusion is suppressed by the light guide 505D. A part of the light beam incident from the light incident part 400 side is emitted from the light output part 410 side as a uniform light beam as a whole while being reflected and collected by the inner surface of the light guide 505D.

  The light guide 505D of the fifth embodiment includes a first light guide 508 located on the end side in the main scanning direction Y and a second light guide 509 located in the center in the main scanning direction Y. The light guide 505D has a distance between the light incident part 400 and the light output part 410 in the first light guide part 508 and a distance between the light incident part 400 and the light output part 410 in the second light guide part 509. Configured differently.

  Specifically, as shown in FIG. 10, the light guide 505 </ b> D is formed in a concave shape in which the light incident portion 400 is recessed toward the light exit portion 410 in the central portion in the main scanning direction Y. For this reason, the light incident portion 400 of the light guide 505 is disposed in the center portion in the main scanning direction Y so as to be separated from the plurality of LEDs 501 serving as light emitting portions. Further, the light incident portion 400 of the light guide 505 increases in distance from the plurality of LEDs 501 as it approaches the central portion in the main scanning direction Y. The light guide 505D is formed in a concave shape in which the depression distance gradually increases from the end in the main scanning direction Y toward the center.

Next, the operation of the copier in this embodiment will be described.
According to the present embodiment, the light guide 505D is formed in a concave shape in which the light incident part 400 is recessed toward the light exit part 410 in the central part in the main scanning direction Y. The amount of light incident from the light unit 400 decreases on the light output unit 410 side. Therefore, the amount of light on the end side in the main scanning direction Y can be increased as compared with the central portion, so that a good light amount distribution in the main scanning direction Y can be obtained.

  According to this embodiment, the same effect as that of the first embodiment can be obtained.

  Further, according to the present embodiment, since the light incident part 400 has a concave curved shape, the desired shape in the main scanning direction Y can be obtained by appropriately adjusting the concave curved shape of the light incident part 400. A light amount distribution can be obtained.

  Next, the copier according to the sixth embodiment will be described with reference to FIG. FIG. 11 is a partially enlarged view showing a light guide 505E having a light-transmitting member and formed in a solid shape. The copying machine according to the 60th embodiment is the same as the copying machine 1 according to the fifth embodiment, except that the light exiting part 410 has a convex shape projecting toward the original G, and the light incident part 400 is not recessed toward the light exiting part 410. It has the same configuration as.

  As shown in FIG. 11, the light guide body 505E of the sixth embodiment is formed in a convex shape in which the light output section 410 protrudes toward the original G side at the center in the main scanning direction Y. The light guide 505E is formed in a convex curved shape in which the protruding distance gradually decreases from the center to the end in the main scanning direction Y.

Next, the operation of the copier in this embodiment will be described.
According to the present embodiment, the light guide 505E has a convex curved shape in which the light exit portion 410 protrudes toward the original G side at the center portion in the main scanning direction Y. The light incident from the light source is refracted toward the end in the main scanning direction Y by the light output unit 410 and is diffused radially to output light. For this reason, the amount of light on the original G surface is small at the center in the main scanning direction Y and large at the end in the main scanning direction Y. Therefore, a good light amount distribution can be obtained in the main scanning direction Y.

  According to this embodiment, the same effect as that of the fifth embodiment can be obtained.

  Next, the copier according to the seventh embodiment will be described with reference to FIG. FIG. 12 is a partially enlarged view showing a light guide 505F having a light-transmitting member and formed in a solid shape. Here, the copier in the seventh embodiment has the same configuration as the copier 1 in the fifth embodiment except for the light guide 505D. Hereinafter, only the light guide 505F different from the copier 1 in the fifth embodiment will be described, and description of other components will be omitted.

  As illustrated in FIG. 12, the light guide 505 </ b> F is a solid light guide having a light transmissive member, similar to the light guide 505 </ b> D of the fifth embodiment. The light guide 505F has a rectangular parallelepiped shape that is long in the main scanning direction Y. The light guide 505F is different from the light guide 505D of the fifth embodiment in that the light entrance 400 (light entrance surface) and the light exit 410 (light exit surface) of the light guide 505F are formed in a planar shape.

  The light guide 505 </ b> F includes a first transmission part 610 corresponding to the first light guide part 508 and a second transmission part 611 corresponding to the second light guide part 509. The light transmittance of the second transmission part 611 is configured to be lower than the light transmittance of the first transmission part 610. The second transmission part 611 is disposed on the light incident part 400 side in the first transmission part 610. The second transmissive portion 611 is arranged so that the thickness of the second light guide portion 509 is thick and gradually becomes thinner toward the first light guide portion 508.

  The light guide 505F is formed integrally with the first transmission part 610 and the second transmission part 611, for example, by two-color molding using light-transmitting resin materials having different light transmittances.

Next, the operation of the copier in this embodiment will be described.
According to the present embodiment, the light guide 505F is arranged so that the second transmission part 611 configured to be lower than the transmittance of the first transmission part 610 corresponds to the second light guide part 509. In the central portion in the main scanning direction Y, the amount of light incident from the light incident unit 400 decreases in the light output unit 410. For this reason, the amount of light on the original G surface is small at the center in the main scanning direction Y and large at the end in the main scanning direction Y. Therefore, the amount of light on the end side in the main scanning direction Y can be increased compared to the central portion. Therefore, a good light amount distribution can be obtained in the main scanning direction Y.

  According to this embodiment, the same effect as that of the fifth embodiment can be obtained.

  As mentioned above, although 1st Embodiment to 7th Embodiment was described as a suitable embodiment, this invention can be implemented with a various form, without being limited to embodiment mentioned above. For example, in the present embodiment, the copying machine 1 is described as an image forming apparatus, and the copying machine includes a color copying machine and a monochrome copying machine. In addition, the present invention is not limited to this, and a printer, a facsimile, and a multifunction machine of these may be used.

  Moreover, in 1st Embodiment and 2nd Embodiment, although the light guide 505 or 505A is made into the concave shape into which the light-incidence part 400 or the light-emitting part 410 becomes depressed, Furthermore, the light-incidence part 400 and the light-emitting part 410 become depressed. It may be configured with a concave shape.

  In the fifth and sixth embodiments, the light guide 505D or 505E has a concave shape in which the light incident portion 400 is recessed or a convex shape in which the light output portion 410 protrudes. A concave shape and a convex shape from which the light output part 410 protrudes may be provided.

  Further, in the seventh embodiment, the light guide 505F has the second transmission part 611 disposed on the light incident part 400 side, but is not limited thereto, and the second transmission part 611 includes the light incident part 400 and the light emission part. What is necessary is just to be arrange | positioned between the parts 410. FIG. For example, the second transmission unit 611 may be disposed on the light output unit 410 side.

  In the first to seventh embodiments, the image reading apparatus 300 is formed integrally with the apparatus main body M. However, the image reading apparatus 300 is not limited to this, and is configured by a separate housing from the apparatus main body M. May be. For example, the image reading apparatus 300 may be configured to be detachable from the apparatus main body M.

  In the first to seventh embodiments, the image reading apparatus 300 constitutes a part of the copying machine 1 as an image forming apparatus. The apparatus used as may be sufficient.

  Moreover, in 1st Embodiment to 7th Embodiment, although LED501 was demonstrated as a light emission part, it is not limited to this. For example, an organic EL (Organic Electro-Luminescence), an optical fiber, or various lamps can be used as the light emitting unit.

  DESCRIPTION OF SYMBOLS 1 ... Copy machine (image forming apparatus), 2a, 2b, 2c, 2d ... Photosensitive drum (image carrier), 16 ... Developing device, 300 ... Image reader, 321 ... First mirror (mirror) ) 322... 2nd mirror (mirror) 323... 3rd mirror (mirror) 340 .. Illumination unit 357... Imaging lens 358... CCD (reading means) 400. , 410... Light emitting part, 501... LED (light emitting part), 505, 505 A, 505 B, 505 C, 505 D, 505 E. , 600... First light reflecting portion, 601... First portion, 602... Second portion, 603... Second light reflecting portion, 610... First transmitting portion, 611. ...... Original, H ... Optical path, N ... Transfer nip (transfer part), X ... Sub-scanning direction, Y ... main scanning direction

Claims (10)

A light emitting unit having a plurality of light emitting members arranged at predetermined intervals in the main scanning direction so that the light emitting surface faces the document side;
A light guide body disposed between the light emitting section and the original and having a light incident section disposed on the light emitting section side and a light exit section disposed on the document side, and is an end portion in the main scanning direction The distance between the light incident part and the light exit part in the first light guide part located on the side, and the light incident part and the light exit part in the second light guide part located in the center part in the main scanning direction A light guide with a different distance between,
One or more mirrors that reflect the light flux from the original to form an optical path;
An imaging lens that forms an image of the light beam reflected by the one or more mirrors;
An image reading apparatus comprising: a reading unit that is disposed at an image forming position of the image forming lens and reads an image of the document based on image formation by the image forming lens. The light guide is
The image reading apparatus according to claim 1, wherein the light incident portion has a concave shape that is recessed toward the light exit portion in the central portion. 3. The image reading apparatus according to claim 1, wherein the light guide has a hollow shape and has a concave shape in which the light exit portion is recessed toward the light incident portion in the central portion. 3. The image reading apparatus according to claim 1, wherein the light guide has a solid shape having a light transmissive member, and has a convex shape in which the light output portion protrudes toward the document in the central portion. A light emitting unit having a plurality of light emitting members arranged at predetermined intervals in the main scanning direction so that the light emitting surface faces the document side;
Arranged between the light emitting part and the original,
A light incident portion disposed on the light emitting portion side;
A light emitting portion disposed on the document side;
A first light guide portion located on the end side in the main scanning direction;
A second light guide portion located in a central portion in the main scanning direction;
A hollow part formed so as to connect the light incident part and the light outgoing part and long in the main scanning direction;
A first light reflecting part having a predetermined light reflectance formed on the inner surface of the hollow part, between the light incident part and the light exit part in the first part corresponding to the first light guide part A hollow light guide having a distance and a first light reflecting portion having a different distance between the light incident portion and the light exit portion in the second portion corresponding to the second light guide portion;
One or more mirrors that reflect the light flux from the original to form an optical path;
An imaging lens that forms an image of the light beam reflected by the one or more mirrors;
An image reading apparatus comprising: a reading unit that is disposed at an image forming position of the image forming lens and reads an image of the document based on image formation by the image forming lens. The first light reflecting portion is configured such that a distance between the light incident portion and the light outgoing portion in the second portion is shorter than a distance between the light incident portion and the light outgoing portion in the first portion. The image reading apparatus according to claim 5, wherein The light guide includes a second light reflecting portion having a light reflectance lower than that of the first light reflecting portion on the light incident portion side and / or the light exit portion side of the second portion on the inner surface of the hollow portion. The image reading apparatus according to claim 5 or 6. The light guide has a substantially uniform distance between the light entrance and the light exit in the main scanning direction,
The image reading apparatus according to claim 7, wherein the second light reflecting unit is disposed on the light incident unit side of the first light reflecting unit. A light emitting unit having a plurality of light emitting members arranged at predetermined intervals in the main scanning direction so that the light emitting surface faces the document side;
Arranged between the light emitting part and the original,
A light incident portion disposed on the light emitting portion side;
A light emitting portion disposed on the document side;
A first light guide portion located on the end side in the main scanning direction;
A second light guide portion located in a central portion in the main scanning direction;
A light transmissive portion formed of a light transmissive member that is formed so as to connect the light incident portion and the light outgoing portion and that is long in the main scanning direction, and includes a second transmissive portion corresponding to the second light guide portion. A solid light guide having a light transmission portion whose light transmittance is lower than the light transmittance of the first transmission portion corresponding to the first light guide portion;
One or more mirrors that reflect the light flux from the original to form an optical path;
An imaging lens that forms an image of the light beam reflected by the one or more mirrors;
An image reading apparatus comprising: a reading unit that is disposed at an image forming position of the image forming lens and reads an image of the document based on image formation by the image forming lens. An image reading apparatus according to any one of claims 1 to 9,
An image carrier on which an electrostatic latent image is formed on the surface based on image information relating to an image of the original read by the image reading device;
A developing device for developing a toner image on the electrostatic latent image formed on the image carrier;
A transfer unit that directly or indirectly transfers a toner image formed on the image carrier to a predetermined sheet;
An image forming apparatus comprising: a fixing unit that fixes the toner image transferred to the predetermined sheet by the transfer unit.

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