JP6037225B2 - Image reading apparatus and image forming apparatus - Google Patents

Description

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

  An image for reading an image by guiding the light of the light source reflected from the document surface on the contact glass to the image sensor while moving the traveling body including at least the light source along the document surface of the document on the contact glass in the sub-scanning direction. An image forming apparatus provided with a reading device is known (for example, Patent Documents 1 and 2).

  The traveling body and the imaging element are housed in a housing having an opening formed on the upper end surface, and the contact glass is attached to the housing and covers the opening.

FIG. 12 is a perspective view showing a housing 217 of the image reading apparatus under development by the present applicant, and FIG. 13 is a sectional view taken along the line DD in FIG.
The housing 217 includes a base member 210 having a bottom surface portion 210c. Further, the base member 210 has side portions 210a that rise vertically from both ends of the bottom surface portion 210c. Further, as shown in FIG. 13, the base member 210 has a rail surface portion 211a formed by being bent at a right angle from the upper end of the side surface portion 210a. A traveling body 239 is placed on the rail surface portion 211a. The housing 217 includes a substantially L-shaped support frame 230 including a placement surface portion 231 on which the contact glass 235 is placed, and a fixed surface portion 232 that vertically falls from the placement surface portion 231a. Yes.

  As shown in FIG. 12, the fixed surface portion 232 has three fastening portions 233a, 233b, and 233c that are recessed toward the side surface portion 210a of the base member 210 in the sub-scanning direction that is the longitudinal direction of the housing 217. ing. The height from the bottom face part 210c of the fastening part fastened with the side part 210a of each fastening part 233a-233c is the same height as shown by the chain line X in the figure.

  As shown in FIG. 13, the fixed surface portion 232 of the support frame 230 is fastened to the side surface portion 210 a of the base member 210 by bolts 150 and nuts 151, and the contact glass 235 is placed on the placement surface portion 231 of the support frame 230. Has been.

  In the image reading apparatus under development by the present applicant, the thickness of the base member 210 is reduced in order to reduce the weight of the apparatus. However, as a result of reducing the thickness of the base member 210, the following problems occurred.

FIG. 14 is a diagram for explaining a problem of the image reading apparatus under development.
As shown in FIG. 14, when a book document B such as a book having a certain number of pages is opened and an image is read, the document surface near the binding margin of the book document B is separated from the contact glass 235, and the book document B is near the binding margin. The image may not be read well. For this reason, the user may read the book document B by pressing it against the contact glass 235 so that the vicinity of the binding margin of the book document B is not separated from the contact glass 235. In this case, the placement surface portion 231 of the support frame 230 is pushed toward the inside of the housing. At this time, a force in the direction indicated by the arrow A in the figure is applied to the fastening portion T between the support frame 230 and the side surface portion 210a of the base member 210. As described above, in the image reading apparatus under development, the thickness of the base member 210 is reduced. Accordingly, the rigidity of the base member 210 is weak, and when a force in the direction indicated by the arrow A in the figure is applied to the fastening portion T between the support frame 230 and the side surface portion 210a of the base member 210, the side surface portion 210a of the base member 210 is deformed. As shown in FIG. 14, it will be bent in a mountain shape with the fastening point T as the apex. As a result, the placement surface portion 231 of the support frame 230 is inclined toward the inside of the housing, and the traveling body 239 that travels directly below the placement surface portion 231 during image reading collides with the placement surface portion 231 and can read the image. There is no problem.

  In addition, the mounting surface portion 231 of the support frame 230 is inclined toward the inside of the housing, so that the position of the contact glass 235 may move toward the inside of the housing. As a result, the distance from the original image of the contact glass 235 to the image sensor becomes short, and the subject is out of the focus range of the image sensor and the read image is out of focus.

  The present invention has been made in view of the above problems, and an object thereof is to provide an image reading apparatus and an image forming apparatus capable of suppressing the mounting surface portion from being inclined toward the inside of the housing.

  In order to achieve the above object, the invention according to claim 1 is reflected from the original surface on the transparent member while moving in the sub-scanning direction along the original surface of the original placed on the plate-like transparent member. In an image reading apparatus including a traveling body that guides light from a light source to an imaging device, and a housing that houses the imaging device and the traveling body, the housing includes a rectangular bottom surface portion and a vertical portion extending from the bottom surface portion. A support frame having a base member having a side surface rising on the surface, a mounting surface portion on which the transparent member is mounted, and a fixed surface portion that vertically falls from the mounting surface portion and is fixed to the side surface portion. Provided, and the side surface portion of the base member and the fixing surface portion of the support frame are fixed at a plurality of different positions in the vertical direction.

According to the present invention, since there are a plurality of fixing portions between the side surface portion of the base member and the fixing surface portion of the support frame in the vertical direction, the following effects can be obtained. That is, when the mounting surface portion of the support frame is pushed toward the inside of the housing, the force applied to the fixed portion is dispersed at a plurality of locations in the vertical direction. Thereby, the side part of the base member can be prevented from being bent outward as compared with an image reading apparatus under development in which the force applied to the fixed part is concentrated in one place in the vertical direction. Therefore, it is an effect that the mounting surface portion of the support frame can be prevented from tilting toward the inside of the housing.
Thereby, even if the thickness of the base member is reduced to reduce the weight of the apparatus, the traveling body can be prevented from hitting the placement surface portion, and the original image can be read. Further, it is possible to prevent the read image from being out of focus.

1 is an external perspective view of an entire copying machine as an image forming apparatus according to an embodiment. 1 is a schematic configuration diagram of a copying machine. The perspective view which shows a scanner. The enlarged block diagram which shows the internal structure of a scanner from the side. The perspective view which shows a moving mechanism. The perspective view which shows the internal structure of a scanner. The perspective view of a housing | casing. The front side view of a housing | casing. The perspective view seen from the A direction of FIG. The rear side view of a housing | casing. FIG. 8 is a cross-sectional view taken along the line B-B in FIG. 7 illustrating a state where a book document is placed on the contact glass and image reading is performed. The perspective view which shows the housing | casing of the image reading apparatus under development. DD sectional drawing of FIG. The figure explaining the subject of the image reading apparatus under development.

Hereinafter, an electrophotographic copying machine (hereinafter simply referred to as copying machine 11) will be described as an example of an embodiment of an image forming apparatus to which the present invention is applied (hereinafter referred to as Embodiment 1).
FIG. 1 is an external perspective view of an entire copying machine 11 as an image forming apparatus according to an embodiment.
In the copying machine 11, a scanner 16 serving as an image reading device is disposed on an upper part of an apparatus main body 15 in which an image forming unit 12, a fixing device 13, a recording medium conveying device 14, and the like are accommodated. Above the scanner 16, an automatic document feeder (ADF) 18 is provided as a document feeder. The ADF 18 is mounted on the scanner 16 so as to be freely opened and closed via a hinge mechanism.

FIG. 2 is a schematic configuration diagram of the copying machine 11.
In FIG. 2, a copying machine 11 as an image forming apparatus fixes an image forming unit 12 for forming a toner image on a recording medium and a toner image on the recording medium formed by the image forming unit 12 to the recording medium. The fixing device 13 is provided. Further, a recording medium conveyance device 14 for feeding the recording medium to the image forming unit 12 is provided.

  The image forming unit 12, the fixing device 13, and the recording medium conveyance device 14 are accommodated in the apparatus main body 15. Further, a scanner 16 that reads a document image and an automatic document feeder (hereinafter simply referred to as ADF) 18 having a pressure plate function as an opening / closing member that transports the document are disposed on the image forming unit 12.

  The ADF 18 includes a document placement table 20 on which a document bundle can be placed, a contact position where the document bundle is placed on the document placement table 20 and a contact position where the document bundle is sent out, and a separation position which is separated from the document bundle. A moving pickup roller 21 is provided. Further, a document transport unit comprising a paper feed belt 22, a reverse roller 23, and a transport roller pair 24 that separates the documents one by one from the document bundle sent out by the pickup roller 21 and transports them toward the slit glass 36 that is a reading position. 25. In addition, a document discharge unit 29 including a conveyance roller pair 27 and a discharge roller pair 28 for discharging the document, which has been read at the reading position, to the document discharge table 26 is provided.

  The paper discharge roller pair 28 includes a drive roller 28a, a driven roller 28b and a driven roller 28c that are in sliding contact with the drive roller 28a, and a switching claw 30 is provided in the vicinity of the paper discharge roller pair 28. . The switching claw 30 moves between the first switching position and the second switching position. When the switching claw 30 is switched to the first switching position, the driving roller 28a and the driven roller 28b The document is discharged to the document discharge table 26. When the switching claw 30 is switched to the second switching position, the document is conveyed to the switchback passage 31 by the driving roller 28a and the driven roller 28c.

  The switchback passage 31 is provided with a pair of switchback rollers 32 that can rotate forward and backward. The document conveyed to the switchback path 31 is conveyed rightward in FIG. 1 by the switchback roller pair 32, and then the switchback roller pair 32 is driven in reverse. Thereby, it is conveyed to the conveyance roller pair 24 via the re-conveyance path. For this reason, the document is reversed and conveyed to the reading position.

  Further, as is known per se, the scanner 16 includes a housing 17 that houses the optical system 34, and a contact glass 35 and a slit glass 36 that are fixedly disposed on the top of the housing 17. In the scanner 16, a document including a closed document or a book is placed on the contact glass 35, and the document P can be read by pressing the document P with the ADF 18. A document automatically conveyed by the ADF 18 is read at the reading position of the slit glass 36. The optical system 34 of the scanner 16 includes a first traveling body 39 having a light source 37 and a first mirror 38, and a second traveling body 42 having a second mirror 40 and a third mirror 41. The optical system 34 includes an imaging lens 43 and a CCD image sensor 44.

  The first traveling body 39 and the second traveling body 42 move to the right from the position shown in FIG. 1, and at this time, the original is illuminated by the light emitted from the light source 37. The reflected light is reflected in the order of the first mirror 38, the second mirror 40 and the third mirror 41, and then enters the CCD image sensor 44 through the imaging lens 43. In this way, the original image is formed on the CCD image sensor 44, whereby the original image is read.

  When the original is read by the ADF 18, the original traveling in the above-described procedure is read with the first traveling body 39 and the second traveling body 42 fixed to the position shown on the right side in FIG.

  A reflective guide plate 65 is provided on the slit glass 36. The reflective guide plate 65 constitutes a white reference for reading a document and reflects light from the light source 37. Further, a guide member 71 is provided between the contact glass 35 and the slit glass 36 so that the guide member 71 scoops up the document that has passed through the slit glass 36 and guides it toward the conveying roller pair 27. It has become.

The image forming unit 12 includes a process cartridge 10 (Y, M, C, BK) as a process unit. In these process cartridges 10 (Y, M, C, BK), an intermediate transfer belt 46 composed of an endless belt wound around a plurality of support rollers is disposed oppositely.
The suffixes Y, M, C, and BK attached to the four process cartridges 10 indicate the specifications for yellow, magenta, cyan, and black. Since the four process cartridges 10 (Y, M, C, and BK) have substantially the same configuration except that the colors of the toners to be used are different, the subscripts K, Y, M, and C are omitted below. I will explain.

  The process cartridge 10 unitarily supports a photosensitive member 45 as a latent image carrier, a charging member 47 as a charging unit, a developing device 49 as a developing unit, and a photosensitive member cleaning device as a cleaning unit. It becomes the composition which became. Each process cartridge 10 can be attached to and detached from the apparatus main body 15 by releasing a stopper (not shown).

  The photoconductor 45 rotates in the clockwise direction in the figure as indicated by the arrow in the figure. The charging member 47 is a roller-shaped charging roller, is in pressure contact with the surface of the photoconductor 45, and is rotated by the rotation of the photoconductor 45. At the time of image formation, a predetermined bias is applied to the charging member 47 by a high voltage power source (not shown) to charge the surface of the photoreceptor 45. The process cartridge 10 uses a roller-shaped charging member 47 that contacts the surface of the photoconductor 45 as a charging unit, but the charging unit is not limited to this, and a non-contact charging method such as corona charging is used. May be.

  The exposure device 48 exposes the surface of the photoconductor 45 on the basis of the image information of the original image read by the scanner 16 or image information input from an external device such as a personal computer, and the surface of the photoconductor 45 is statically exposed. An electrostatic latent image is formed. The exposure device 48 included in the image forming unit 12 uses a laser beam scanner system using a laser diode, but the exposure unit may have other configurations such as an LED array.

  The developing device 49 has a developing container 53 containing powdered toner, and the electrostatic latent image is visualized by the toner. The photoconductor cleaning device 55 cleans residual toner remaining on the surface of the photoconductor 45 that has passed through a position facing the intermediate transfer belt. The photoconductor cleaning device 55 includes a cleaning container that receives the toner removed from the photoconductor 45. The toner in the cleaning container is transported to a waste toner container (not shown) by the toner transport device.

  The four process cartridges 10 form toner images for the respective colors of yellow, cyan, magenta, and black on the photoreceptor 45, respectively. The four process cartridges 10 are arranged in parallel in the surface movement direction of the intermediate transfer belt 46, and transfer the toner images formed on the respective photoreceptors 45 so as to be superimposed on the intermediate transfer belt 46 in order. A visible image is formed on the belt 46.

  In FIG. 1, a primary transfer roller 50 as a primary transfer unit is disposed at a position facing each photoconductor 45 across the intermediate transfer belt 46. A primary transfer bias is applied to the primary transfer roller 50 by a high voltage power supply (not shown), and a primary transfer electric field is formed between the primary transfer roller 50 and the photosensitive member 45. By forming a primary transfer electric field between the photoconductor 45 and the primary transfer roller 50, the toner image formed on the surface of the photoconductor 45 is transferred to the surface of the intermediate transfer belt 46. One of a plurality of stretching rollers that stretch the intermediate transfer belt 46 is rotated by a drive motor (not shown), so that the intermediate transfer belt 46 moves in the direction of arrow A in the drawing. A full color image is formed on the surface of the intermediate transfer belt 46 by sequentially transferring the toner images of the respective colors on the surface of the intermediate transfer belt 46 moving on the surface.

  In this way, the superimposed toner image transferred onto the intermediate transfer belt 46 is secondarily transferred onto the recording medium by the action of the secondary transfer roller 56. The transfer residual toner adhering to the intermediate transfer belt 46 after the transfer is removed by the belt cleaning device 52. The cleaning container of the cleaning device 52 also stores toner, and the toner is conveyed to a waste toner container (not shown).

  Further, the recording medium transport device 14 is disposed below the four process cartridges 10. The recording medium transport device 14 has a paper feed cassette 57 that stores a recording medium S made of transfer paper, resin sheet, or the like. Further, the sheet feeding roller 58 that contacts the uppermost recording medium S of the recording medium bundle housed in the sheet feeding cassette and a registration roller pair 59 are provided. The uppermost recording medium S is sent out in the direction of arrow B in FIG. The sent recording medium S is fed between the intermediate transfer belt 46 and the secondary transfer roller 56 disposed opposite to the intermediate transfer belt 46 at a predetermined timing by the rotation of the registration roller pair 59.

  When the recording medium S passes between the intermediate transfer belt 46 and the secondary transfer roller 56, a transfer voltage is applied to the secondary transfer roller 56, so that the superimposed toner image on the intermediate transfer belt 46 is recorded on the recording medium. Secondary transfer. In this way, a toner image is formed on the recording medium by the image forming means 12.

  The recording medium on which the toner image is formed passes through the fixing device 13, and at this time, the toner image on the recording medium formed by the image forming unit 12 is fixed on the recording medium. The recording medium S on which the image is fixed by the fixing device 13 is discharged onto the recording medium discharge stand 61 by the discharge roller pair 60.

  The recording medium discharge table 61 is formed between the apparatus main body 15 that houses the image forming means 12 and the scanner 16. In the present embodiment, the in-body discharge type copier 11 is opened between the apparatus main body 15 and the scanner on the downstream side in the discharge direction of the recording medium S by the discharge roller pair 60.

  A switching lever 62 is provided on the upstream side of the paper discharge roller pair 60, and this switching lever 62 is used when copying on the back surface of the recording medium S and when copying on the front surface of the recording medium S is completed. It can be switched to the reversing passage 63 side.

  That is, when the rear end of the recording medium S is sandwiched between the paper discharge roller pair 60, the paper discharge roller pair 60 is driven in reverse, and the switching lever 62 is switched to a position communicating with the reverse passage 63. It is conveyed toward the reversing passage 63. A reversing roller pair 64 is provided in the reversing path 63, and the recording medium conveyed through the reversing path 63 by the reversing roller pair 64 is conveyed again to the secondary transfer roller 56 side.

  FIG. 3 is a perspective view showing the scanner 16. Although not shown in the drawing for the sake of convenience, an ADF 18 (not shown) is mounted on the scanner 16 and supported by a hinge so as to be swingable, thereby opening and closing the upper surface of the scanner 16. It is possible. A contact glass 35 and a slit glass 36 as transparent members are provided on the upper surface of the scanner 16.

  FIG. 4 is an enlarged configuration diagram showing the internal configuration of the scanner 16 from the side. As shown in the figure, the housing 17 of the scanner 16 houses a first traveling body 39 as a first moving body and a second traveling body 42 as a second moving body. An image forming lens 43, a CCD (Charge Coupled Device) image sensor 44 as an image sensor, and the like are also housed.

  The first traveling body 39 moves along the surface of the contact glass 35 while holding the light source 37 and the first mirror 38. At this time, light emitted from the light source 37 is irradiated toward the image reading target surface of the document D via the contact glass 35, and the reading light reflected by the image reading target surface is received by the first mirror 38.

  The second traveling body 42 moves along the surface of the contact glass 35 with a predetermined distance from the first traveling body 39 while holding the second mirror 40 and the third mirror 41. Yes. Then, the reading light transmitted from the first mirror 38 of the first traveling body 39 is sequentially reflected by the second mirror 40 and the third mirror 41 and then incident on the imaging lens 43. The reading light incident on the imaging lens 43 is imaged on the light receiving surface of the CCD image sensor 44 and read as an image. Note that while the first traveling body 39 travels the distance L, the second traveling body 42 travels the distance L / 2. Thereby, the optical path length of the optical system 34 is kept constant.

  When a sheet document is automatically read continuously, the document is conveyed onto the slit glass 36 by the ADF 18, and a reflected light image passing through the slit glass 36 is formed on the CCD image sensor 44. At that time, the first traveling body 39 and the second traveling body 42 are fixed, and the image of the conveyed sheet original is read. On the other hand, when reading a book document such as a book having a certain number of pages, the ADF 18 is opened once and the book document is set on the contact glass 35. Thereafter, by closing the ADF 18, the book document can be pressed by the pressure plate portion 101 (see FIG. 1) provided on the ADF 18. These reading operations are started by pressing a start key provided on the operation unit 102 shown in FIG.

  FIG. 5 is a perspective view showing a moving mechanism for moving the first traveling body 39 and the second traveling body 42 of the scanner 16. In the figure, a first traveling body 39 that holds a light source 37 and a first mirror 38 is attached to a drive wire 171. The drive wire 171 is stretched between idle pulleys 179a and 179B, and is wound around a pulley 172 that is rotatably fixed to the second traveling body 42 and a wire pulley 175 that is fixed to the drive shaft. ing. The drive shaft 174 is connected to a drive motor 178 via a timing pulley 176 and a timing belt 177. When the wire pulley 175 as a drive transmission member of the drive shaft 174 is rotationally driven by the drive motor 178, the drive wire 171 is driven to move the first traveling body 39 at a predetermined speed v, and the second pulley 172 is provided. The traveling body moves at a speed of v / 2.

  One end of the movable range of the first traveling body 39 in the sub-scanning direction is a home position as a standby position of the first traveling body 39. When the first traveling body 39 is at a position slightly advanced to the other end side from the home position, the first traveling body 39 is detected by the position sensor 173. A position shifted by a predetermined distance from the position by the position sensor 173 is the home position. In the scanner 16, a stepping motor is used as the drive motor 178 described above. The number of drive pulses for the stepping motor and the moving distance of the first traveling body 39 are strictly correlated. Therefore, the position of the first traveling body 39 in the sub-scanning direction can be accurately grasped from the number of drive pulses for the drive motor 178 from the time when the first traveling body 39 is detected by the position sensor 173.

FIG. 6 is an exploded perspective view showing an outline of the housing 17 of the scanner 16.
As shown in FIG. 6, the housing 17 includes a base member 110 having a bottom surface portion 110c formed by bending a sheet metal, and side plates 140a fixed to both ends of the base member 110 in the sub-scanning direction (longitudinal direction). 140b. The housing 17 also includes support frames 130a and 130b that support the contact glass 35, a rail member 120 for the second traveling body 42 to travel, and the like.

  The base member 110 is formed by bending a sheet metal, and includes a rectangular bottom surface portion 110c and side surface portions 110a and 110b rising vertically from both ends in the main scanning direction (short direction) of the bottom surface portion 110c. . Further, the base member 110 has side plate fixing portions 110d and 110e that rise vertically from both ends of the bottom surface portion 110c in the sub-scanning direction (longitudinal direction). The base member 110 includes first rail surface portions 111a and 111b for the first traveling body 39 to travel. The first rail surface portions 111a and 111b are formed by bending 90 ° from the upper ends of the side surface portions 110a and 110b to the outside of the housing.

  The side plates 140a and 140b disposed at both ends of the casing 17 in the sub-scanning direction (longitudinal direction) are known to the side plate fixing portions 110d and 110e and the side surface portions 110a and 110b of the base member 110 such as screws, caulking, and welding. It is fixed by the method.

  The rail member 120 for the second traveling body 42 to travel has a square pipe shape, near both ends in the main scanning direction (short direction) of the base member 110, and both ends in the main scanning direction (short direction) of the side plates 140a and 140b. It is fixed in the vicinity by a known method such as screw, caulking, or welding.

  The support frames 130a and 130b provided on the front side and the rear side of the casing that supports the contact glass 35 are formed by bending a sheet metal and have an L-shaped cross section. Each support frame 130a, 130b has placement surface portions 131a, 131b on which the contact glass 35 is placed. In addition, the mounting surface portions 131a and 131b have fixing surface portions 132a and 132b for fixing to the side surface portions 110a and 110b of the base member 110 formed by being bent at right angles from the outer ends in the main scanning direction. Yes.

  In the present embodiment, the support frame 130 is provided and placed on a member different from the base member 110 provided with the first rail surface portion 111a on which the first traveling body 39 travels and the rail member 120 on which the second traveling body travels. Surface portions 131a and 131b were provided. Thereby, for example, when the light source 37 held by the first traveling body 39 has reached the end of its life and the light source 37 held by the first traveling body 39 or the first traveling body 39 is replaced, the support frames 130a and 130b are removed from the casing 17. Remove and work. Thereby, the mounting surface portions 131a and 131b do not interfere with the work. Accordingly, the replacement work of the first traveling body 39 and the light source can be easily performed.

  In this embodiment, in order to reduce the weight of the apparatus, the base member 110 is thinner than the rail member 120 and the support frames 130a and 130b. However, by reducing the thickness of the base member 110, the rigidity of the housing 17 is reduced. If the casing 17 has low rigidity, the casing 17 may be twisted or bent when the scanner 16 is carried, such as when it is attached to the image forming apparatus. As described above, when the housing 17 is twisted or bent, the positional accuracy of the members housed in the housing 17 is deteriorated, and the quality of the read image may be deteriorated.

  For this reason, in this embodiment, the rail member 120 is formed into a square pipe shape and is reinforced by the rail member 120. Thereby, even if the thickness of the base member 110 is reduced, the housing 17 can be prevented from being twisted or bent. In the present embodiment, the thickness of the base member 110 is 0.6 mm.

FIG. 7 is a perspective view of the housing 17.
As shown in FIG. 7, first to third front fastening portions recessed at the front side surface portion 110 a side of the base member 110 by drawing at three places in the sub-scanning direction of the front fixed surface portion 132 a of the front support frame 130 a. 133a, 134a, 135a.

FIG. 8 is a front side view of the housing 17.
As shown in FIG. 8, a reference member 160 is provided between the slit glass 36 and the contact glass 35 for abutting the original and positioning the original when placing the original on the contact glass 35. It has been. The first front fastening portion 133a on one end side in the sub-scanning direction of the front support frame 130a (upstream side in the moving body moving direction when reading an image) is provided near the reference member 160. Further, the second front side fastening portion 134a is provided at the center in the sub-scanning direction of the front side support frame 130a. Further, the third front side fastening portion 135a is provided near the other end portion in the sub-scanning direction (downstream side in the traveling body moving direction at the time of image reading).

  The first front side fastening portion 133a and the second front side fastening portion 134a are provided with two through holes in the vertical direction in the drawing and through holes through which the bolts 150 pass, and are fastened at two vertical directions. On the other hand, the third front side fastening portion 135a is provided with a through hole (not shown) through which the bolt 150 passes, and is fastened at one place in the vertical direction.

  The front support frame 130a is fixed to the base member 110 as follows. That is, the bolt 150 is inserted into a through hole (not shown) of each fastening portion 133a, 134a, 135a and a through hole (not shown) provided in the front side surface portion 110a of the base member 110. Then, a nut 151 is screwed into a bolt 150 penetrating into the housing from a through hole (not shown) of the front side surface portion 110a of the base member 110, and the front support frame 130a is fastened to the front side surface portion 110a of the base member 110. .

FIG. 9 is a perspective view seen from the direction A in FIG.
As shown in FIG. 9, first to third recesses are also formed on the rear side surface 110b side of the base member 110 by drawing processing at three places in the sub-scanning direction of the rear fixed surface portion 132b of the rear support frame 130b. It has rear side fastening parts 133b, 134b, 135b.

FIG. 10 is a rear side view of the housing 17.
As shown in FIG. 10, the first rear side fastening portion 133b on one end side in the sub-scanning direction of the rear support frame 130b (upstream side in the moving body moving direction when reading an image) is also near the reference member 160, just like the front side. Is provided. In addition, the second rear side fastening portion 134b is also provided at the center portion in the sub-scanning direction, like the front side. Further, the third rear side fastening portion 135b is also provided in the vicinity of the other end portion in the sub-scanning direction (downstream side in the traveling body moving direction at the time of image reading) similarly to the front side.

  The first rear side fastening part 133b is provided with a through hole (not shown) through which the bolt 150 passes through one place at the upper part and two places at the lower part. The second rear side fastening part 134b and the third rear side fastening part 135b are One through hole is provided. The through hole provided in the upper part of the first rear side fastening portion 133b is provided at the same height as the through hole of the second rear side fastening portion 134b and the through hole of the third rear side fastening portion 135b.

  The rear support frame 130b is also fixed to the rear side surface portion 110b of the base member 110 in the same manner as the front support frame 130a. That is, the bolts 150 are inserted into through holes (not shown) of the respective fastening parts 133b, 134b, 135b and through holes (not shown) provided in the rear side surface part 110b of the base member 110. Then, the nut 151 is screwed into the bolt 150 penetrating into the housing from the through hole of the rear side surface portion 110b of the base member 110, and the rear support frame 130b is fastened to the rear side surface portion 110b of the base member 110. .

FIG. 11 is a cross-sectional view taken along the line B-B in FIG. 7 showing how the book original B is placed on the contact glass 35 and image reading is performed.
When reading an image by opening a book document B such as a book having a certain number of pages, the document surface near the binding margin of the book document B may be separated from the contact glass 35 and the image near the binding margin may not be read satisfactorily. is there. For this reason, the user may read the book document B by pressing it against the contact glass 35 so that the vicinity of the binding margin of the book document B is not separated from the contact glass 35. In this case, the placement surface portion 131a of the front support frame 130a is pushed toward the inside of the housing. At this time, a force is applied in the outer direction (right direction in the drawing) of the housing 17 at a fastening portion (a portion sandwiched between the bolt 150 and the nut 151) between the front support frame 130a and the front side surface portion 110a of the base member 110.

In the present embodiment, as described above, the thickness of the base member 110 is reduced for weight reduction, the rigidity of the front side surface portion 110a is weak, and deformation such as bending is likely to occur.

  As shown in FIG. 12, when the number of fixing points is one in the vertical direction, the force is concentrated on the fixing point. As a result, as shown in FIG. 14, the front side surface portion 110a bends in a mountain shape with the fixed portion as the apex, and the placement surface portion 131a is inclined toward the inside of the housing. As a result, when the book document image is read, the first traveling body 39 may collide with the placement surface portion 131a, and the image reading may not be performed. Further, the contact glass 35 moves to the inside of the housing, and the distance between the CCD image sensor 44 and the document surface approaches. As a result, the CCD image sensor 44 is out of focus and there is a possibility that a read image is out of focus.

  The book document B is abutted against the reference member 160 shown in FIG. 8 and positioned and placed at the end of the contact glass 35 on the slit glass 36 side. Accordingly, since the pressing force of the user is applied in the vicinity of the reference member 160, the force is concentrated on the fastening portion of the first front side fastening portion 133a arranged near the reference member 160. Further, the central portion in the sub-scanning direction of the front side surface portion 110a is more easily bent than the end portion to which the side plate 140 is fixed. Therefore, when the user presses the book document B against the contact glass 35, the portion between the vicinity of the reference member 160 of the front side surface portion 110a and the central portion in the sub-scanning direction is most easily bent. For this reason, as shown by the two-dot chain line in FIG. 8, the placement surface portion 131a is inclined more toward the inside of the housing than the end portion in the center portion in the sub-scanning direction.

  For this reason, in this embodiment, the 1st front side fastening part 133a and the 2nd front side fastening part 134a are being fixed to two places up and down. Thereby, as shown in FIG. 11, the force added to a fastening location is disperse | distributed to an up-down direction. As a result, even if the thickness of the base member 110 is reduced and the rigidity of the front side surface portion 110a is weak, it is possible to suppress the front side surface portion 110a from bending outward due to the force applied to the fixed portion. Thereby, it can suppress that the mounting surface part 131a of the front side support frame 130a inclines to the housing | casing 17 inner side. As a result, it is possible to suppress the first traveling body 39 from colliding with the placement surface portion 131a when reading the image of the book document B.

  In addition, the front side surface portion 110a is fixed at two locations from the vicinity of the reference member 160 of the front side surface portion 110a that is easily bent when the user presses the book document B against the contact glass 35 to the center portion in the sub-scanning direction. Can be effectively suppressed.

  The rigidity of the rear side surface portion 110b is also reduced due to the thinning of the base member 110. When the user presses the book document B against the contact glass, the placement surface portion 131b of the rear support frame 130b is also inside the casing. There is a risk of tilting to the side. For this reason, as shown in FIGS. 9 and 10, the first fastening portions 133b of the rear support frame 130b are fastened to the rear side surface portion 110b at two locations in the vertical direction. Therefore, also in the rear support frame 130b, when the user presses the book document B against the contact glass 35, the force applied to the fastening portion is dispersed in two places in the vertical direction, and the rear side surface portion 110b is prevented from being bent. can do. Thereby, it is possible to suppress the placement surface portion 131b of the rear support frame 130b from inclining toward the inside of the housing, and the first traveling body 39 hits the placement surface portion 131b when reading the image of the book document B. Can be suppressed. In addition, the back side is also fixed at two places in the vertical direction between the vicinity of the reference member 160 where the back side surface portion 110b is easily bent and the center portion in the sub scanning direction when the user presses the book document B against the contact glass 35. ing. Thereby, when the user presses the book document B against the contact glass 35, it is possible to effectively suppress the rear side surface portion 110b from being bent.

  Moreover, in this embodiment, although the fastening location was provided in two places up and down, you may provide three or more fastening locations in an up-down direction.

  In the present embodiment, the differential mirror method is used in which the second traveling body that holds the first traveling body, the second mirror, and the third mirror is traveled to read the document image, but the light source, the mirror, and the imaging element are retained. It is also possible to read the original by moving the unit. In the present embodiment, a CCD image sensor is used as the image sensor, but a document image may be read using a contact image sensor (CIS).

What has been described above is an example, and the present invention has a specific effect for each of the following aspects.
(Aspect 1)
The light of the light source 37 reflected from the original surface on the transparent member while moving in the sub-scanning direction along the original surface of the original placed on a plate-like transparent member such as the contact glass 35 is applied to the CCD image sensor 44 or the like. In an image reading apparatus such as a scanner 16 that includes a traveling body such as a first traveling body 39 and a second traveling body 42 that are guided to an image sensor, and a housing 17 that houses the image sensor and the traveling body, the housing 17 includes: A base member 110 having a rectangular bottom surface portion 110c and side surface portions 110a and 110b rising vertically from the bottom surface portion 110c, mounting surface portions 131a and 131b for mounting a transparent member, and the mounting surface portion 131a. , 131b, and support frames 130a and 130b having fixed surface portions 132a and 132b fixed to the side surface portions 110a and 110b. Side portion 110a of over scan members 110, 110b and the support frame 130a, 130b of the fixing surface 132a, and 132b, and fixed with a plurality of different positions in the vertical direction.
By providing such a configuration, as described in the embodiment, it is possible to suppress the placement surface portions 131a and 131b of the support frames 130a and 130b from being inclined toward the inside of the housing.

(Aspect 2)
Further, in (Aspect 1), from the vicinity of the document reference position for positioning the document when placing the document on a transparent member such as the contact glass 35 to the central portion of the housing in the sub-scanning direction. The side surface portions 110a and 110b of the base member 110 and the fixing surface portions 132a and 132b of the support frames 130a and 130b are fixed at a plurality of different positions in the vertical direction.
With such a configuration, as described in the embodiment, it is possible to effectively suppress the placement surface portions 131a and 131b of the support frames 130a and 130b from being inclined toward the inside of the housing.

(Aspect 3)
In addition, document transport means such as ADF 18 for transporting the document to a reading position for reading the document image is provided.
With such a configuration, a book document or the like can be pressed against a transparent member such as the contact glass 35 to read an image, and a sheet document can be read using a document conveying unit such as the ADF 18.

(Aspect 4)
An image forming apparatus including an image reading unit such as a scanner 16 that reads an image on a document surface and an image forming unit that forms an image on a recording medium S based on image information read by the image reading unit. As the reading unit, any one of (Aspect 1) to (Aspect 3) image reading apparatus was used.
With such a configuration, the book document can be reliably copied.

11: Copier 12: Image forming means 16: Scanner 17: Housing 18: ADF
34: optical system 35: contact glass 37: light source 38 first mirror 39: first traveling body 40: second mirror 41: third mirror 42: second traveling body 43: imaging lens 44: CCD image sensor 110: base Member 110a: Front side surface portion 110b: Rear side surface portion 110c: Bottom surface portion 111a, 111b: First rail surface portion 120: Rail member 130a: Front side support frame 130b: Rear side support frame 131a, 131b: Placement surface portion 132a: Front side fixed Surface portion 132b: rear fixed surface portion 133a: first front side fastening portion 133b: first rear side fastening portion 134a: second front side fastening portion 134b; second rear side fastening portion 135a: third front side fastening portion 135b: third rear side Fastening portion 150: bolt 151: nut 160: reference member

Japanese Patent No. 3789287 Japanese Patent No. 3375032

Claims (4)

A traveling body for guiding the light of the light source reflected from the document surface on the transparent member to the image sensor while moving in the sub-scanning direction along the document surface of the document placed on the plate-shaped transparent member;
In an image reading apparatus including the imaging element and a housing that houses the traveling body,
The housing includes a base member having a rectangular bottom surface portion and a side surface portion vertically rising from the bottom surface portion, a mounting surface portion on which the transparent member is mounted, and a vertical surface from the mounting surface portion. A support frame having a fixed surface portion that is lowered and fixed to the side surface portion;
An image reading apparatus characterized in that a side surface portion of the base member and a fixed surface portion of the support frame are fixed at a plurality of different positions in the vertical direction. The image reading apparatus according to claim 1.
The side surface portion of the base member and the support frame between the vicinity of the document reference position for aligning the document when the document is placed on the transparent member and the central portion in the sub-scanning direction of the housing An image reading apparatus characterized in that fixing to the fixed surface portion is performed at a plurality of positions that are different from each other in the vertical direction. The image reading apparatus according to claim 1 or 2,
An image reading apparatus comprising an original conveying means for conveying an original to a reading position for reading an original image. An image reading unit for reading an image on a document surface;
An image forming apparatus comprising: an image forming unit that forms an image on a recording medium based on image information read by the image reading unit;
An image forming apparatus using the image reading apparatus according to claim 1 as the image reading unit.

Images