JP2007306054A - Image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus capable of preventing deterioration in the read accuracy of an image by allowing the vibration of a drive motor to hardly deliver to a carriage. <P>SOLUTION: The image reading apparatus including guide rails 11, 11, the carriage movably supported along the guide rails 11, 11, and the drive motor for driving the carriage, includes: a cover chassis 30 for configuring a chassis part and side wall parts of the image reading apparatus; and a frame member 70 integrally provided with the guide rails 11, 11 as separate components, a motor fitting part 34 fitting the drive motor is provided to a side of the cover chassis 30 and a fitting fixing part 80 fitting and fixing the frame member 70 to the cover chassis 30 is arranged at position apart from the motor fitting part 34 so as to attain a configuration whereby the vibration of the drive motor is hardly delivered to the carriage. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image reading apparatus that scans and reads an image of a document on a platen glass with a carriage movably supported along a guide rail.

An image reading apparatus included in a scanner, a facsimile, a copying machine, or the like includes a carriage on which a light source and a reflection mirror are mounted, as shown in Patent Document 1, and an image of an original placed on a platen glass by the carriage. The original image is read by scanning and guiding the scanned image to an imaging unit such as a CCD. This image reading apparatus is provided with a guide rail that supports the carriage so as to be movable below the platen glass, and a drive motor that drives the carriage.
JP 2001-42453 A

  In a conventional image reading apparatus, the guide rail is formed integrally with a frame member that constitutes a chassis portion of the image reading apparatus. A drive motor for driving the carriage is fixedly attached to the frame member. However, if the drive motor is fixed to the frame member formed integrally with the guide rail, when the carriage is moved, the vibration of the drive motor is transmitted to the carriage via the guide rail, and the carriage vibrates. There has been a problem that the image reading accuracy is lowered.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an image reading apparatus capable of preventing a reduction in image reading accuracy by making it difficult for vibration of a drive motor to be transmitted to a carriage. There is to do.

  In order to solve the above-mentioned problems, the invention according to claim 1 of the present application reads a document image on a platen glass supported by a guide rail installed below the platen glass and movably along the guide rail. In an image reading apparatus including a carriage for scanning and a drive motor for driving the carriage, a cover chassis constituting a chassis part and a side wall part of the image reading apparatus, and a frame member integrally provided with the guide rail Are provided as separate parts, and a motor mounting portion for mounting the drive motor is provided on the cover chassis side.

  The invention according to claim 2 of the present application is the image reading apparatus according to claim 1, wherein an attachment fixing portion for attaching and fixing the frame member to the cover chassis is provided near or at one end near the middle portion of the guide rail. And the motor mounting portion is provided at a position disposed in the vicinity of the other end portion of the guide rail on the cover chassis.

  According to a third aspect of the present invention, in the image reading apparatus according to the first aspect, the guide rail includes a pair of guide rails installed in parallel at a predetermined interval, and the frame member is attached to the cover chassis. An attachment fixing portion to be attached and fixed is provided in the vicinity of one guide rail, and the motor attachment portion is provided at a position arranged in the vicinity of the other guide rail on the cover chassis. .

  According to a fourth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the motor mounting portion is arranged at one corner provided with a document setting reference position on the platen glass. It arrange | positions in the vicinity of corners other than a part, It is characterized by the above-mentioned.

  According to the invention described in claim 1 of the present application, the cover chassis constituting the chassis part and the side wall part of the image reading apparatus and the frame member formed integrally with the guide rail are provided as separate parts, and the drive motor is provided. Since the motor mounting part to be mounted is provided on the cover chassis side, when the carriage is moved, the vibration of the drive motor mounted on the cover chassis is less likely to be transmitted to the carriage carried on the guide rail. Can be prevented.

  According to the invention described in claim 2 of the present application, the mounting fixing portion is provided in the vicinity of the middle portion of the guide rail or in the vicinity of one end portion, and the motor mounting portion is in the vicinity of the other end portion of the guide rail on the cover chassis. Since the mounting fixing portion is located away from the motor mounting portion, the vibration of the drive motor transmitted from the cover chassis side to the frame member side via the mounting fixing portion can be reduced. A decrease in image reading accuracy can be prevented.

  According to the invention described in claim 3 of the present application, the mounting fixing portion is provided in the vicinity of one guide rail, and the motor mounting portion is provided in a position arranged in the vicinity of the other guide rail on the cover chassis. Therefore, the mounting and fixing portion is located away from the motor mounting portion, and the vibration of the drive motor transmitted from the cover chassis side to the frame member side through the mounting and fixing portion can be reduced, thereby preventing deterioration in image reading accuracy. be able to.

  According to the invention described in claim 4 of the present application, the motor mounting portion is disposed in the vicinity of the other corners other than the one corner provided with the document setting reference position on the platen glass. Is located away from the motor mounting portion, and the vibration of the drive motor transmitted to the original placed in alignment with the original setting reference position can be reduced, so that the reading accuracy of the image can be prevented from being lowered. In particular, when reading a small-size document, the document is placed at a position sufficiently away from the drive motor, so that the vibration of the drive motor transmitted to the document is further reduced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing an image forming apparatus including an image reading apparatus according to an embodiment of the present invention. First, a schematic overall configuration of the image forming apparatus will be described with reference to FIG. The image forming apparatus according to the present invention may be any of a copier, a facsimile machine, a printer, or a so-called multifunction machine having these functions as long as the image forming apparatus includes an image reading device. The image forming apparatus 1 shown in FIG. 1 includes a recording unit 2 installed on the lower side and a reading unit 3 installed on the upper side. The recording unit 2 includes a recording device 4, a paper feed cassette 5, and a recording paper discharge tray 6. The paper stored in the paper feed cassette 5 is fed to the recording device 4. After recording, the paper is discharged to the recording paper discharge tray 6.

  The reading unit 3 scans and reads an image of an original, an operation panel 7 attached to a side wall portion on the front side of the image reading device 10, and one side of the image reading device 10 on the upper side. And a document presser cover 8 attached so as to be openable and closable by a hinge mechanism that does not. An automatic paper feeder (ADF device) 20 that automatically feeds a document is attached to one end of the document pressing cover 8.

  FIG. 2 is a side sectional view showing the detailed configuration of the image reading apparatus 10 and the automatic paper feeder 20. The automatic paper feeder 20 includes a document tray 21 on which a plurality of documents are stacked and held, a laterally U-shaped transport path 22, a paper discharge tray 23 on which the transported documents are stacked and held, and a document on the document tray 21. Pick-up roller 24 and paper feed roller 25 for feeding the paper to the conveyance path 22, a conveyance roller 26 for conveying the document by nipping the conveyance path 22, a discharge roller 27 provided near the exit of the conveyance path 22, and a reading position And a CIS reading unit 28 having a contact image sensor (hereinafter referred to as “CIS”) that reads an image of a document at P2.

  FIG. 3 is a schematic plan view showing the configuration of the image reading apparatus 10. As shown in FIGS. 2 and 3, in the image reading device 10, each component is arranged on a cover chassis 30 that constitutes a chassis portion and a side wall portion of the image reading device 10. The cover chassis 30 is made of synthetic resin, and includes a substantially rectangular flat plate-like chassis portion (bottom surface portion) 31 and a side wall portion 32 that stands up around the outer periphery of the chassis portion 31. The inside is a carriage storage portion 33. As shown in FIG. 2, an upper cover 40 that covers the upper portion of the carriage storage portion 33 is attached, and a platen glass 41 is installed on the upper surface portion 40 a of the upper cover 40. In addition, illustration of the upper cover 40 is abbreviate | omitted in FIG. On the other hand, a pair of guide rails 11, 11 whose longitudinal direction extends in the left-right direction are laid in parallel on the front side and the back side inside the carriage storage portion 33. A full rate carriage 12 and a half rate carriage 15 which are supported at both ends by the guide rails 11 and 11 are installed. These are movable in the left-right direction along the guide rails 11 and 11 in the carriage housing portion 33.

  The guide rails 11 and 11 have a substantially rectangular cross-sectional shape protruding upward from the chassis portion 31 of the carriage storage portion 33, and the upper surfaces thereof are planar sliding surfaces 11a and 11a. The full-rate carriage 12 includes a main body portion 12a having both ends thereof mounted on the sliding surfaces 11a and 11a of the guide rails 11 and 11, a light source lamp 13 and a reflection mirror 14 mounted on the main body portion 12a. Yes. The half-rate carriage 15 includes a main body portion 15a, a flat plate-like support member 16 attached to the main body portion 15a and mounted on the sliding surfaces 11a, 11a of the guide rails 11, 11. A pair of reflecting mirrors 17 and 17 are provided on the upper side and the lower side of the support member 16. An imaging unit 18 and an inverter device 19 are installed in the carriage storage unit 33. The imaging unit 18 is a CCD imaging unit including an imaging lens 18a that converges incident reflected light, and a CCD image sensor (photoelectric element) 18b that converts an optical image generated by the convergent light into image data. The inverter device 19 is a device for stabilizing the irradiation light of the light source lamp 13. On the other hand, reference numeral 80 shown in FIG. 3 is an attachment fixing portion for attaching and fixing a frame member 70 described below, in which the guide rails 11 and 11 are integrally provided, to the cover chassis 30. As shown in the figure, the mounting and fixing portion 80 has one guide rail 11 (the right end portion 11b is disposed adjacent to the motor mounting portion 34) on the back side in the carriage housing portion 33. 11) in the vicinity of the intermediate portion (both side portions) and in the vicinity of the left end portion 11c (both side portions), in the vicinity of the intermediate portion of the other guide rail 11 disposed on the near side in the carriage storage portion 33, and the right end portion 11b. It is provided in the vicinity (both sides) of the left end portion 11c.

  A belt drive mechanism 50 is installed inside the guide rails 11 and 11. As shown in FIG. 3, the belt drive mechanism 50 is installed at drive pulleys 51 and 51 installed at the inner positions of the right end portions 11b and 11b of the guide rails 11 and 11, and at the inner positions of the left end portions 11c and 11c. Driven pulleys 53 and 53 are provided, and endless belts 56 and 56 are wound between the drive pulleys 51 and 51 and the driven pulleys 53 and 53. The drive pulleys 52 and 52 installed at the inner positions of the right end portions 11b and 11b of the guide rails 11 and 11 and the driven pulleys 54 and 54 installed at the inner positions of the left end portions 11c and 11c are provided. Endless belts 57 and 57 are wound between 52 and 52 and driven pulleys 54 and 54. One belt 56, 56 is fixed to the full rate carriage 12, and the other belt 57, 57 is fixed to the half rate carriage 15. The drive pulleys 51, 51 and the drive pulleys 52, 52 are all attached to a drive shaft 58, the driven pulleys 53, 53 are attached to a rotating shaft 64, and the driven pulleys 54, 54 are attached to a rotating shaft 65.

  On the other hand, a motor mounting portion 34 that is separated from the carriage storage portion 33 by a side wall portion 32 is provided outside the carriage storage portion 33 on the cover chassis 30 and at the right end portion on the back side of the image reading apparatus 10. . A drive motor 60 is attached to the motor attachment portion 34 via a plate-like support member 61 and fixed by screws. On the other hand, one end of the drive shaft 58 protrudes into the motor mounting portion 34, a pulley 59 attached to the drive shaft 58 protruding into the motor mounting portion 34, and a pulley 62 attached to the rotary shaft 60a of the drive motor 60. Between them, a transmission belt 63 is stretched over and the rotation of the drive motor 60 is transmitted to the drive pulleys 51 and 51 and the drive pulleys 52 and 52. The ratio of the diameters of the drive pulley 51 and the drive pulley 52 is approximately ½. Thus, the scanning speed and scanning distance of the half-rate carriage 15 with respect to the scanning speed and scanning distance of the full rate carriage 12 are both set to be approximately ½.

  By the circumferential movement of the belts 56 and 57 driven by the drive motor 60, the full rate carriage 12 and the half rate carriage 15 move from the left end to the right direction along the guide rails 11 and 11 in the carriage housing portion 33. At that time, as shown in FIG. 2, the original on the platen glass 41 is irradiated with light from the light source lamp 13 of the full-rate carriage 12, and the reflected light from the original is sequentially reflected by the reflection mirrors 14, 17, and 17. By being guided to the image unit 18, the image of the document is read.

  When the image reading apparatus 10 configured as described above reads a document image as a flatbed scanner, the document pressing cover 8 is closed and the document placed on the platen glass 41 is pressed and fixed. In this state, the original image is read by the image reading apparatus 10. On the other hand, when reading an original image using the automatic paper feeder 20, the original fed from the original tray 21 to the conveyance path 22 is reversed so as to make a U-turn from above to below along the conveyance path 22. Then, when reaching the reading position P1 and passing through the reading position P1, the image reading apparatus 10 in which the full-rate carriage 12 and the half-rate carriage 15 are aligned with the reading position P1 reads the image on the front side of the document. . Further, when the original is transported through the transport path 22 and passes the reading position P2, the image on the back side of the original is read by the CIS reading unit 28. Thereafter, the paper is discharged to the paper discharge tray 23.

  Here, the configuration of the exterior parts of the image reading apparatus 10 and the mounting structure of the drive motor 60 will be described. FIG. 4 is an exploded perspective view of an exterior part of the image reading apparatus 10. As shown in the figure, the exterior component of the image reading apparatus 10 includes a cover chassis 30, an upper cover 40, and a frame member 70 attached to the lower surface side of the cover chassis 30. The cover chassis 30 is a molded product made of a synthetic resin, and is integrally formed of a chassis component installed at the bottom of the image reading apparatus, which has been a separate part, and an exterior cover part surrounding the side of the image reading apparatus. It is. The chassis 31 in the carriage housing 33 is provided with openings 31 a and 31 a for inserting and arranging the guide rails 11, an opening 31 b for installing the imaging unit 18, and the inverter device 19. For this purpose, an opening 31c is formed. Further, a screw hole 80a that opens to the lower surface side of the chassis portion 31 is provided at a position corresponding to the attachment fixing portion 80 on the side of the openings 31a and 31a. A motor mounting portion 34 is formed at the right end of the cover chassis 30 on the back side, and an operation panel installation portion 35 is formed on the front side.

  The upper cover 40 is a molded product of synthetic resin, and includes a flat upper surface portion 40a and a side wall portion 40b formed on the outer periphery of the lower surface side of the upper surface portion 40a, and an opening 40c is formed in the center portion. A platen glass 41 is installed in the opening 40c. The platen glass 41 has a rectangular shape, and a document setting reference position A for aligning the corner of the document to be placed is provided at one corner. The document setting reference position A is located at the left end portion on the back side of the image reading device 10 when the upper cover 40 is attached to the image reading device 10.

  The frame member 70 is a metal sheet metal member, and is integrally formed by connecting opposite inner side surfaces of the guide rails 11 and 11 arranged in parallel at a predetermined interval by a plate-like support portion 71. A flange portion 72 is formed at the lower end of each guide rail 11, 11, and a screw insertion hole 80 b is formed at a position corresponding to the mounting fixing portion 80 of the flange portion 72. The mounting fixing portion 80 is configured by the screw hole 80 a of the cover chassis 30 and the screw insertion hole 80 b of the frame member 70. The frame member 70 is installed on the lower surface side of the cover chassis 30, and is fixed to the cover chassis 30 integrally by fixing screws (not shown) inserted through the screw insertion holes 80 b into the screw holes 80 a of the cover chassis 30. . In this state, the guide rails 11 and 11 are inserted into the openings 31 a and 31 a from the lower side and protrude into the carriage storage portion 33. Further, the upper surface of the support portion 71 is exposed to the opening portion 31b and the opening portion 31c, and the imaging unit 18 and the inverter device 19 are installed on the exposed support portion 71.

  The image reading apparatus 10 includes a cover chassis 30 that constitutes a chassis part and a side wall part of the image reading apparatus 10, and a frame member 70 that is integrally attached with the guide rails 11 and 11 as separate parts, and is driven. A motor mounting portion 34 for mounting the motor 60 is provided on the cover chassis 30 side. Thereby, when scanning an image, the vibration of the drive motor 60 is not easily transmitted to the full-rate carriage 12 and the half-rate carriage 15 carried on the guide rails 11, 11, so that the reading accuracy of the image can be prevented from being lowered.

  Further, the motor mounting portion 34 is provided at a position disposed in the vicinity of the right end portion 11b of the one guide rail 11 on the cover chassis 30, and the mounting fixing portion 80 for mounting the frame member 70 to the cover chassis 30 is provided. By providing the guide rail 11 in the vicinity of the middle portion or in the vicinity of the left end portion 11 c, the mounting fixing portion 80 is arranged at a position away from the motor mounting portion 34. Thereby, the vibration of the drive motor 60 transmitted from the cover chassis 30 side to the frame member 70 side via the attachment fixing portion 80 is reduced. Further, the mounting and fixing portion 80 is also provided in the vicinity of the guide rail 11 on the near side of the carriage housing portion 33, but this mounting and fixing portion 80 is also disposed at a position away from the motor mounting portion 34. The vibration of the drive motor 60 transmitted from the cover chassis 30 side to the frame member 70 side via the mounting fixing portion 80 is also reduced. As a result, the vibration of the drive motor 60 is less likely to be transmitted to the full rate carriage 12 and the half rate carriage 15, so that it is possible to prevent the image reading accuracy from being lowered.

  Further, the motor mounting portion 34 is disposed in the vicinity (lower side) of the right corner portion on the back side of the image reading apparatus 10 that is one corner portion on the opposite side to the corner portion where the document setting reference position A of the platen glass 41 is provided. As a result, the document placed in alignment with the document setting reference position A is arranged at a position away from the drive motor 60, so that the vibration of the drive motor 60 transmitted to the document can be reduced and the image reading accuracy can be reduced. Can be prevented. In particular, when reading a small-size document, the document aligned with the document setting reference position A is placed at a position sufficiently away from the drive motor 60, so that the vibration of the drive motor 60 transmitted to the document is reduced. .

  Further, in the image reading apparatus 10 of the above-described embodiment, since the imaging unit 18 is attached to the support portion 71 of the frame member 70, the vibration of the drive motor 60 is not easily transmitted to the imaging unit 18. This also prevents a decrease in image reading accuracy. In addition, the full-rate carriage 12, the half-rate carriage 15, the imaging unit 18, the inverter device 19, and the like, which are precision parts that are easily affected by vibration, are mounted on the frame member 70 side, resulting in vibration of the drive motor 60. It is possible to reduce the failure of the component parts of the image reading apparatus 10 to be performed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims, the specification, and the drawings. Is possible. It should be noted that any shape, structure, and material not directly described in the specification and drawings are within the scope of the technical idea of the present invention as long as the effects and advantages of the present invention are exhibited. For example, the specific shapes of the cover chassis 30 and the frame member 70 are not limited to those shown in the above embodiment. In particular, the position of the motor mounting portion 34 of the cover chassis 30 is not limited to the position shown in the above-described embodiment, and may be in the vicinity of a corner other than the corner where the document setting reference position A of the platen glass 41 is provided. The image reading device 10 may be disposed in the vicinity of the left corner on the near side of the image reading device 10 or in the vicinity of the right corner on the near side of the image reading device 10.

  Further, the position of the attachment fixing portion 80 for attaching and fixing the frame member 70 to the cover chassis 30 is not limited to the position shown in the above embodiment, and a full-rate carriage in which the vibration of the drive motor 60 is carried on the guide rails 11 and 11. 12 and the half-rate carriage 15 may be provided at other positions as long as they are provided at positions away from the motor mounting portion 34 so that they are not easily transmitted to the half-rate carriage 15. In the above-described embodiment, the mounting fixing portion 80 is provided in the vicinity of one guide rail 11 in which the right end portion 11 b is disposed adjacent to the motor mounting portion 34 and both of the other guide rails 11. However, in addition to this, the attachment fixing portion 80 may be provided only in the vicinity of one of the guide rails 11. Further, the full-rate carriage 12 and the half-rate carriage 15 are not limited to those equipped with the light source lamp 13 and the reflection mirrors 14, 17, and 17 as in the above embodiment. It is also possible to use a camera equipped with an imaging unit.

1 is a perspective view illustrating an overall configuration of an image forming apparatus including an image reading apparatus according to an embodiment of the present invention. 2 is a side cross-sectional view illustrating configurations of an image reading device and an automatic paper feeder. FIG. 1 is a schematic plan view showing a configuration of an image reading apparatus. It is a disassembled perspective view which shows the exterior components of an image reading apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Image reading apparatus 11, 11 Guide rail 12 Full-rate carriage 15 Half-rate carriage 18 Imaging unit 19 Inverter apparatus 20 Automatic paper feeder 30 Cover chassis 31 Chassis part 32 Side wall part 33 Carriage storage part 34 Motor attachment part 35 Operation panel installation part 40 Upper cover 41 Platen glass 50 Belt drive mechanism 60 Drive motor 61 Support member 70 Frame member 71 Support part 72 Flange part 80 Fixing part 80a Screw hole 80b Screw insertion hole A Document setting reference position

Claims (4)

An image provided with a guide rail installed under the platen glass, a carriage that is movably supported along the guide rail and that reads and scans an image of a document on the platen glass, and a drive motor that drives the carriage In the reading device,
A cover chassis that constitutes a chassis part and a side wall part of the image reading device, and a frame member that is integrally provided with the guide rail are provided as separate parts, respectively.
An image reading apparatus, wherein a motor mounting portion for mounting the drive motor is provided on the cover chassis side. The image reading apparatus according to claim 1,
An attachment fixing portion for attaching and fixing the frame member to the cover chassis is provided in the vicinity of the middle portion of the guide rail or in the vicinity of one end portion thereof, and the motor attachment portion is provided on the guide rail on the cover chassis. An image reading apparatus provided at a position disposed in the vicinity of the other end. The image reading apparatus according to claim 1,
The guide rail comprises a pair of guide rails installed in parallel at a predetermined interval,
An attachment fixing portion for attaching and fixing the frame member to the cover chassis is provided in the vicinity of one guide rail, and the motor attachment portion is disposed at a position arranged in the vicinity of the other guide rail on the cover chassis. An image reading apparatus characterized by being provided. The image reading apparatus according to any one of claims 1 to 3,
An image reading apparatus, wherein the motor mounting portion is arranged in the vicinity of a corner other than the one corner provided with the document setting reference position on the platen glass.

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