JP2009267921A - Automatic document feeder and document scanner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic document feeder (ADF) and a document scanner in which image quality is prevented from being deteriorated by vibration and maintenance is easily performed. <P>SOLUTION: The ADF includes a second scanner unit 60, an inner guide 19, and a spring 18. The second scanner unit 60 has a scanner frame 12 for internally holding optical components and scans a document. The inner guide 19 is mounted on the scanner frame 12, covers at least a part of the outside of the scanner frame 12, and supports the scanner frame 12. The spring 18 is placed between the scanner frame 12 and the inner guide 19 so as to apply pressing force in such a direction that the scanner frame 12 and the inner guide 19 are separated. A separation preventive part 172 prevents the scanner frame 12 and the inner guide 19 from being separated by pressing force of the spring 18. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an automatic document feeder and a document reading apparatus including the automatic document feeder. Specifically, the present invention relates to a configuration for attaching a reading unit included in an automatic document feeder and a document reading device.

  Conventionally, a document can be read by both sides of a document only by conveying the document by an automatic document feeder (ADF, auto document feeder) and passing the document once through the document transport path from upstream to downstream (so-called one-pass). The device is known. The document reading apparatus having this configuration includes two scanner units for the front side and the back side in order to read both sides of the document with one pass. One of the two scanner units is provided on the ADF side, and the other is provided on the document reading apparatus main body side.

As this type of document reading apparatus, there is a structure disclosed in, for example, Patent Document 1. The document reading apparatus of Patent Document 1 includes a reduction optical system reading unit on the main body side and a contact optical system reading unit on the ADF side.
JP 2002-101259 A

  In the document reading apparatus configured as described above, since the reading unit provided in the ADF is installed in the vicinity of the document transport path, it is exposed to vibration during document transport. In particular, the vibration when the original is fed into the ADF is large, and from the viewpoint of preventing the reading image quality from being deteriorated, a configuration that transmits the vibration during the feeding to the reading unit as much as possible is required.

  In addition, since the reading unit provided in the ADF is arranged in a narrow document transport path, cleaning or replacement of parts during maintenance is not easy, and there is room for improvement in this respect.

  The present invention has been made in view of the above circumstances, and a main object of the present invention is to provide an automatic document feeder that prevents a deterioration in image quality due to the influence of vibration and facilitates maintenance work.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to an aspect of the present invention, an automatic document feeder having the following configuration is provided. That is, the automatic document feeder includes a document conveyance path for conveying a document, a reading unit, a support member, and an elastic member. The reading unit includes a frame for holding an optical component therein, and reads a document conveyed along the document conveyance path. The support member is attached to the frame, covers at least a part of the outside of the frame, and supports the frame. The elastic member is disposed between the frame and the support member so as to apply a pressing force in a direction in which the frame and the support member are separated.

  Thereby, even if the support member vibrates, it is buffered by the elastic member, so that the vibration transmitted to the frame can be reduced. Therefore, it is possible to prevent the reading quality of the document from being deteriorated due to vibration.

  In the automatic document feeder, the reading unit is preferably a reduction optical system reading unit.

  This makes it possible to exhibit the advantages of the reading unit of the reduction optical system, in which the reading accuracy is higher and the reading speed is higher than that of the reading unit of the contact optical system, while compensating for the disadvantage of the reduction optical system that is weak against vibration. Accordingly, it is possible to provide an automatic document feeder that realizes high reading quality.

  The automatic document feeder preferably includes a detachment preventing unit that prevents the frame and the support member from detaching due to the pressing force of the elastic member.

  Thereby, it can prevent that a flame | frame and a supporting member detach | leave by the pressing force of an elastic member, and can exhibit the buffering effect of the said vibration by the said elastic member appropriately.

  In the automatic document feeder, it is preferable that the separation preventing portions are provided in pairs.

  Thereby, it can prevent by the detachment prevention part that the attitude | position of a flame | frame leans excessively with respect to a supporting member.

  In the automatic document feeder, the separation preventing portion is formed at a position corresponding to the claw portion formed on one of the frame and the support member and on the other side, and contacts the claw portion. A possible contact portion.

  Accordingly, it is possible to obtain an effect of preventing the frame and the support member from being detached with a simple configuration. Further, since the support member and the frame can be detached without using a special tool or the like, maintenance work is facilitated.

  In the automatic document feeder, it is preferable that the support member is formed with a guide portion that constitutes a part of the document conveyance path and guides the conveyance of the document.

  As a result, the supporting member has both the role of supporting the frame and the role of guiding the document, so that the apparatus can be configured compactly, and the number of parts can be reduced to reduce the cost. In addition, since the supporting member guides the conveyance of the document, vibration generated by the conveyance of the document can be weakened by the buffering action of the elastic member. As a result, it is possible to prevent the reading quality from being deteriorated due to the vibration caused by the conveyance of the document.

  In the automatic document feeder, it is preferable that the frame and the support member are detachable.

  Accordingly, the support member and the frame can be attached and detached, and the frame is supported by the support member. Therefore, the reading unit can be easily removed by removing the frame from the support member during maintenance or the like. Therefore, maintainability is improved.

  In the automatic document feeder, the frame preferably includes a positioning unit for positioning the reading unit.

  Accordingly, the reading unit can be accurately positioned at the reading position of the document while preventing the influence of vibration transmission from the support member to the frame, so that the reading quality can be improved.

  According to another aspect of the present invention, there is provided a document reading apparatus including the automatic document feeder.

  Accordingly, it is possible to provide a document reading apparatus that prevents reading quality from being deteriorated due to vibration and realizes high reading accuracy.

  It is preferable that the original reading apparatus can read both sides of the original conveyed by the automatic original conveying apparatus in one pass.

  In other words, the reading unit disposed in the automatic document feeder provided in the document reading apparatus having this configuration is particularly suitable for applying the present invention because it is exposed to vibration during document transportation.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external perspective view of a copy facsimile multifunction device (multifunction device) 20 including an image scanner device 10 as a document reading device provided with an automatic document feeder 25 according to an embodiment of the present invention. FIG. 2 is a front sectional view showing the configuration of the automatic document feeder 25 and the image scanner device 10 of the present embodiment.

  A copy facsimile multifunction machine 20 shown in FIG. 1 includes an image scanner device 10 that functions as a book scanner and an auto document feed scanner on the upper part of the multifunction machine 20. In addition, the multifunction machine 20 includes an operation panel 77 for instructing the number of copies, a facsimile transmission destination, a document reading, and the like.

  Further, the multifunction machine 20 includes a main body 78 having an image forming unit that forms an image on a sheet as a recording medium, and a sheet feeding cassette 79 that sequentially supplies the sheet. The main body 78 includes a transmission / reception unit (not shown) for transmitting image data via a communication line.

  Next, the image scanner device 10 included in the multifunction machine 20 will be described with reference to FIG. As shown in FIG. 2, the image scanner device 10 includes a platen glass 22 and a document table cover 21. The document table cover 21 is provided with an automatic document feeder (auto document feeder, ADF) 25. In addition, the image scanner device 10 includes a first scanner unit 50 and a second scanner unit 60 for reading an image of a document.

  When the image scanner device 10 is used as an auto document feed scanner, the ADF 25 transports originals one by one. The image on the front side (first side) of the original is read by the first scanner unit 50, and the image on the back side (second side) of the original is read by the second scanner unit 60.

  On the other hand, when the image scanner device 10 is used as a book scanner, a user places a book document to be read on the platen glass 22 and presses it with the document table cover 21 so that the book document does not move. Secure to. In this state, the first scanner unit 50 can read the image of the document.

  As shown in FIG. 2, the ADF 25 provided in the document table cover 21 includes a document tray 23 provided above the document table cover 21 and a discharge tray 24 provided below the document tray 23. The ADF 25 includes an ADF main body portion 16 and a cover portion 11 that covers the upper side thereof. As shown in the front cross-sectional view of FIG. 3, the cover portion 11 can be rotated upward about the cover rotation shaft 43 and supported by the ADF main body portion 16 through the cover rotation shaft 43. ing.

  As shown in FIG. 2, a curved (U-shaped) document transport path 30 that connects the document tray 23 and the discharge tray 24 is formed inside the document table cover 21. With this configuration, the documents set on the document tray 23 are separated one by one, conveyed along the document conveyance path 30, and discharged to the discharge tray 24. An instruction to start reading a document can be given by the operation panel 77 shown in FIG.

  Next, the configuration of each part of the ADF 25 will be described in detail along the document conveyance path 30.

  As shown in FIG. 2, a pickup roller (feeding portion) 31 is disposed at a location where the document is supplied from the document tray 23 to the document transport path 30. A separation roller 32 is provided on the downstream side of the pickup roller 31, and a counter roller 37 is disposed to face the separation roller 32.

  The pickup roller 31 is configured to be rotatable about a shaft 45 of the separation roller 32 from a position indicated by a solid line in the drawing to a position indicated by a two-dot chain line. Under normal conditions, the pickup roller 31 is held at an upper position indicated by a solid line. On the other hand, when the original is fed, the pickup roller 31 is rotated downward to come into contact with the end of the uppermost original among the originals set on the original tray 23. With this configuration, when the pickup roller 31 is driven, the uppermost document on the document tray 23 is fed into the ADF 25.

  Further, an inner guide 19 is disposed so as to face the pickup roller 31. The inner guide 19 is disposed in a range from the pickup roller 31 to a registration roller 39 (described later) in the document conveyance path 30 and is formed as a guide portion that contacts the document being conveyed and guides the direction of the document. Yes. The inner guide 19 is supported by the support shaft 41 of the registration roller 39.

  The document is fed to the separation roller 32 by driving the pickup roller 31 and is nipped between the separation roller 32 and the opposing roller 37 disposed on the inner guide 19 side. The documents are separated one by one by a rotationally driven separation roller 32 and conveyed downstream of the document conveyance path 30.

  On the downstream side of the separation roller 32, a registration roller 39 provided on the inner guide 19 side and a counter roller that is paired with the registration roller 39 are disposed. The registration roller 39, together with the opposing roller, temporarily stops and loosens the leading side of the document conveyed by the separation roller 32, and conveys it downstream while removing the slackness after a predetermined time. Thereby, the skew of the original is corrected.

  A plurality of conveying rollers 33, 34, and 35 are provided on the downstream side of the registration roller 39. In addition, rollers are disposed so as to face the transport rollers 33, 34, and 35, respectively. The document conveyed downstream by the driving of the registration roller 39 is nipped by the conveyance rollers 33, 34, and 35 and the rollers facing them, and further conveyed downstream.

  A first document reading position 80 is set between the two conveying rollers 34 and 35, and a platen roller 29 is disposed at the first document reading position 80. A document passing through the first document reading position 80 is scanned and read by a first scanner unit 50 described later.

  The first scanner unit 50 will be described. The first scanner unit 50 is disposed on the main body 78 side, and is disposed below the ADF 25 and the platen glass 22. The first scanner unit 50 includes a light source 51, reflection mirrors 52, 53, 54, a condenser lens 55, and a charge coupled device (CCD) 56. The light source 51 irradiates light to the first document reading position 80 (or the platen glass 22) of the ADF 25, and the reflection mirrors 52, 53, and 54 reflect the reflected light from the document. The reflected light is converged by the condenser lens 55, and the converged light is configured to form an image at the CCD 56 portion.

  The light source 51 and the reflection mirror 52 of the first scanner unit 50 are configured to be movable. As described above, when the image scanner device 10 is used as a book scanner, the light source 51 and the reflection mirror 52 of the first scanner unit 50 are moved along the platen glass 22. As a result, the document placed on the platen glass 22 can be read.

  On the other hand, when the image scanner device 10 is used as an auto document feed scanner, the light source 51, the reflection mirror 52, and the like are moved to a position facing the first document reading position 80 as shown in FIG. Keep it. By driving the ADF 25 in this state, the first scanner unit 50 can scan and read the front side surface of the document that is transported through the document transport path 30 and passes the first document reading position 80.

  In the first scanner unit 50, the reflected light from the original is guided to the CCD 56 as described above to form an image, and the CCD 56 outputs an electrical signal corresponding to the image information of the original. This signal is appropriately converted and transmitted to the image forming unit provided in the multifunction device 20. Then, the transmitted image information is transferred to a sheet as a recording medium by the image forming unit, thereby realizing a copy function of the multifunction machine 20.

  In the document transport path 30, a second document reading position 90 is set on the downstream side of the first document reading position 80 (downstream of the transport roller 35). The back side of the document passing through the second document reading position 90 is scanned and read by a second scanner unit 60 described below.

  The second scanner unit (reading unit) 60 will be described. The second scanner unit 60 is installed inside the document conveyance path 30 so as to be in contact with the document conveyance path 30 configured in a U shape from the inside. The second scanner unit 60 includes a scanner frame (frame) 12 held inside the ADF 25. The scanner frame 12 is configured to support components and the like constituting the internal optical system and to cover and protect the outside.

  A reading glass (reading portion) 42 for reading the back side of the document is provided at the bottom of the scanner frame 12 (the portion in contact with the document conveyance path 30). The reading glass 42 is disposed at a position corresponding to the second document reading position 90.

  Further, a platen roller 38 is disposed in the ADF 25 main body so as to face the second document reading position 90 of the scanner frame 12. With this configuration, when the original conveyed by the conveying roller 35 reaches the platen roller 38, the original is scanned and read while being conveyed by the platen roller 38.

  Next, the scanner frame 12 will be described. The inner guide (support member) 19 is attached to the scanner frame 12. As described above, the inner guide 19 is supported by the support shaft 41, and the second scanner unit 60 is held at a predetermined position in the ADF 25 via the inner guide 19.

  A contact roller 40 is provided at the bottom of the scanner frame 12 so as to face the discharge roller 36. With this configuration, the document read by the second scanner unit 60 is nipped between the contact roller 40 and the discharge roller 36 and is guided to the discharge tray 24 by driving the discharge roller 36.

  Next, the reduction optical system configured in the second scanner unit 60 will be described. As shown in FIG. 2, the second scanner unit 60 includes a light source 61, reflection mirrors 62, 63, 64, 65, a condenser lens 67, and a charge coupled device (CCD) 57 as an image sensor. ing. These parts are all arranged inside the scanner frame 12.

  The light source 61 is disposed so as to face the reading glass 42, and can irradiate light to the second document reading position 90 through the reading glass 42. The reflection mirrors 62, 63, 64, 65 are configured to reflect the reflected light from the document so that it is further diffracted and guide it to the condenser lens 67. The condensing lens 67 converges the light to form an image on the portion of the CCD 57, and the CCD 57 outputs an electrical signal corresponding to the image information of the document, like the CCD 56 in the first scanner unit 50. This signal is also appropriately converted and transmitted to the image forming unit provided in the multifunction machine 20.

  The document whose contents on both the front and back sides are read at the two document reading positions as described above is conveyed by being nipped by the discharge roller 36 and the contact roller 40 and discharged to the discharge tray 24. In this way, the so-called one-pass type image scanner device 10 is configured, which allows double-sided scanning only by allowing the document to pass through the document transport path 30 once.

  Next, with reference to FIG. 4 etc., the structure of the 2nd scanner unit 60 and the inner guide 19 is demonstrated in detail. FIG. 4 is an external perspective view schematically showing the second scanner unit 60 and the inner guide 19 as viewed obliquely from above.

  As described above, the inner guide 19 is attached to the scanner frame 12. The inner guide 19 is made of resin, and as shown in FIG. 4, is configured in a cover shape so as to cover the upper side of the scanner frame 12 over a wide range.

  The upper surface of the inner guide 19 is formed as a guide portion 17 that guides a document to be conveyed. In the guide portion 17, the opposing roller 37 and the registration roller 39 are arranged.

  By attaching the scanner frame 12 of the second scanner unit 60 to the inner guide 19, the scanner frame 12 can rotate about the support shaft 41 together with the inner guide 19. That is, when a document is jammed, cleaned, or when parts are replaced, the second scanner unit 60 is rotated upward to open the document transport path 30 so that the jammed document can be removed. It is configured as follows. As a result, maintainability is improved.

  Hereinafter, this point will be specifically described. In a normal state, the scanner frame 12 is positioned inside the document conveyance path 30 as shown in FIG. The “horizontal posture” here means a posture parallel to the installation surface of the ADF 25 (image scanner device 10). That is, in the state shown in FIG. 2, the conveyance of the document supplied from the document tray 23 is arranged so as to be appropriately guided by the upper surface of the inner guide 19 attached to the scanner frame 12. In this state, the glass surface (reading surface) of the reading glass 42 faces directly downward, and the contact roller 40 is in a state where the original can be pressed between the discharge roller 36.

  When performing maintenance or the like on the second scanner unit 60, first, the cover unit 11 of the ADF 25 is rotated upward to lift up, and the cover unit 11 is opened as shown in FIG. To do. As a result, the nip between the registration roller 39 and the separation roller 32 is released, and the upstream half of the document conveyance path 30 is opened.

  Next, the scanner frame 12 is lifted to rotate from the position shown in FIG. 2 (closed position) about the support shaft 41 and pull upward to move to the position shown in FIG. 3 (open position). With this rotation, the contact roller 40 releases the contact with the discharge roller 36 and is separated from the document conveyance path 30. By rotating the scanner frame 12 to the open position in this manner, the bottom surface side of the scanner frame 12 can be exposed as shown in FIG. 3, and most of the downstream side of the document conveyance path 30 can be opened. .

  Further, as shown in FIG. 4, a positioning portion 59 is formed in the lower portion of the scanner frame 12. The positioning portion 59 is configured to be able to position the scanner frame 12 by contacting the shaft of the platen roller 38. With this configuration, when the original is read by rotating the scanner frame 12 to the closed position, the second scanner unit 60 can be held so as not to swing around the support shaft 41. Further, since the reading glass 42 can be accurately positioned with respect to the second original reading position 90, the original can be read appropriately.

  Next, a structure for attaching the scanner frame 12 to the inner guide 19 will be described. A spring 18 as an elastic member is disposed between the scanner frame 12 and the inner guide 19 as shown in FIG. The spring 18 is disposed at appropriate positions on the front side and the back side of the apparatus so as not to interfere with the optical axes of the optical components inside the scanner frame 12.

  Further, a plurality of separation preventing portions 172 to 175 are installed so as to connect the scanner frame 12 and the inner guide 19, thereby preventing the scanner frame 12 and the inner guide 19 from being separated.

  Next, the attachment structure of the scanner frame 12 to the inner guide 19 will be described in more detail with reference to FIGS. FIG. 5 is a front sectional view of the scanner frame 12 and the inner guide 19, and FIG. 6 is a side sectional view of the scanner frame 12 and the inner guide 19.

  As shown in FIG. 5, the spring 18 is disposed between the inner guide 19 and the scanner frame 12. The spring 18 is configured as a compression coil spring, and is arranged so as to apply a pressing force in such a direction that the inner guide 19 and the scanner frame 12 are separated from each other.

  More specifically, the inner guide 19 is formed with a spring mounting portion 191, and the scanner frame 12 is also formed with a spring mounting portion 121. The spring mounting portion 191 on the inner guide 19 side has, for example, a configuration in which a cylindrical member is formed at the tip of the cross rib. By fitting the cylindrical member inside the spring 18, the spring It is comprised so that 18 can be hold | maintained in a predetermined position and a predetermined direction. Further, the spring mounting portion 121 on the scanner frame 12 side is formed, for example, as a circular concave portion into which the spring 18 can be inserted, and is configured to hold the spring 18 in a predetermined position. With this configuration, the spring 18 is pressed and held in a predetermined position, and a pressing force in a direction in which the scanner frame 12 and the inner guide 19 are separated from each other can be applied to the scanner frame 12 and the inner guide 19.

  Further, the inner guide 19 and the scanner frame 12 are connected to each other via separation preventing portions 172 to 175 arranged at four locations, thereby preventing the scanner frame 12 from being separated from the inner guide 19. Yes.

  First, the two separation preventing portions 172 and 173 arranged on the right side surface of the scanner frame 12 (the surface on the side close to the document tray 23 and the discharge tray 24) will be described. These two detachment preventing portions 172 and 173 are disposed at positions that are paired with each other on the front side and the back side of the apparatus (one side and the other side in the document width direction). In the present specification, the “document width direction” means a direction orthogonal to the document thickness direction and orthogonal to the document conveyance direction. The separation preventing portion 172 includes a claw portion 122 formed integrally with the scanner frame 12 and a contact surface 192 formed on the inner guide 19. Similarly, the separation preventing portion 173 includes a claw portion 123 formed integrally with the scanner frame 12 and a contact surface 193 disposed on the inner guide 19.

  In the detachment preventing portion 172, as shown in FIG. 5, the claw portion 122 extends a part of the edge of the scanner frame 12 upward, and then has a flat protrusion with a rectangular cross section at the tip. It has a formed configuration. On the other hand, the inner guide 19 is formed with a rectangular through hole 182 formed in a substantially horizontal direction, and a contact surface 192 is formed at the lower edge of the through hole 182. The protruding portion of the claw portion 122 is inserted into the through hole 182 in a horizontal direction.

  Some play is formed between the claw portion 122 and the through hole 182, and the claw portion 122 is configured to move to some extent within the through hole 182. Accordingly, the scanner frame 12 can move relative to the inner guide 19 within the range of this play.

  In this configuration, when the scanner frame 12 is moved away from the inner guide 19 by the pressing force of the spring 18, the contact surface 192 eventually comes into contact with the claw portion 122 as shown in FIG. The movement of the scanner frame 12 is prevented. The claw portion 122 is configured to prevent the scanner frame 12 and the inner guide 19 from being separated (separated) vertically.

  Similarly to the above-described separation preventing portion 172, the opposite-side separation preventing portion 173 has a through hole 183 having a contact surface 193 formed in the lower edge portion, and the claw portion 123 moves to some extent in the through hole 183. Can do. Then, when the claw 123 is caught on the contact surface 193, the scanner frame 12 can be prevented from being detached from the inner guide 19.

  Next, the remaining two separation prevention units 174 and 175 will be described. The two separation preventing portions 174 and 175 are arranged in the vicinity of the end portion of the support shaft 41 of the registration roller 39 and in a paired position on the front side and the back side (one end and the other end in the document width direction) of the apparatus. Has been. The separation preventing part 174 includes a claw part 124 formed integrally with the scanner frame and a contact surface 194 formed on the inner guide 19. Similarly, the separation preventing portion 175 includes a claw portion 125 formed integrally with the scanner frame 12 and a contact surface 195 formed on the inner guide 19.

  In the separation preventing portion 174, the claw portion 124 is formed on the surface of the scanner frame 12 facing one end side in the document width direction, as shown in FIG. Further, the claw portion 124 is formed as a flat protruding portion having a rectangular cross section protruding horizontally. On the other hand, a claw storage portion 184 is integrally formed in the inner guide 19 at a position corresponding to the claw portion 124. The claw storage portion 184 is formed in a hollow rectangular tube shape, and the contact surface 194 is formed on the bottom thereof. A claw portion 124 is inserted horizontally in the claw storage portion 184.

  The claw storage portion 184 is formed in a vertically long shape so that the claw portion 124 can move to some extent within the claw storage portion 184. Accordingly, the scanner frame 12 can move relative to the inner guide 19 within the movable range of the claw portion 124.

  With this configuration, when the scanner frame 12 is moved away from the inner guide 19 by the pressing force of the spring 18, the contact surface 194 of the nail storage portion 184 eventually comes into contact with the nail portion 124, and a further scanner frame. 12 movements are blocked. The hook 124 is configured to prevent the scanner frame 12 and the inner guide 19 from being separated (separated) vertically.

  Similarly to the above-described detachment preventing unit 174, the detachment preventing unit 175 on the opposite side is formed with a claw storage unit 185 having a contact surface 195 formed on the bottom, and the claw unit 125 is inserted into this claw storage unit 185. The claw portion 125 can move to some extent along the claw storage portion 185. Then, when the claw portion 125 is caught on the contact surface 195, the scanner frame 12 can be prevented from being detached from the inner guide 19.

  As described above, in each of the separation preventing portions 172 to 175, the claw portions 122 to 125 are configured to be movable within a slight stroke range inside the through holes 182 and 183 or the claw storage portions 184 and 185. When the scanner frame 12 is positioned on the ADF main body 16 side by the positioning portion 59, the respective claw portions 122 to 125 are slightly separated from the contact surfaces 192 to 195 (floating state). Yes.

  Thereby, it is possible to effectively suppress the impact and vibration applied to the inner guide 19 from being transmitted to the scanner frame 12 side. That is, even when an impact and vibration due to document conveyance are applied to the inner guide 19, the vibration is not propagated to the scanner frame 12 via the separation preventing portions 172 to 175 (contact surfaces 192 to 195). Since the vibration of the inner guide 19 is always transmitted to the scanner frame 12 via the spring 18, the vibration is greatly buffered by the elasticity of the spring 18. As a result, it is possible to prevent vibration from being directly transmitted to the scanner frame 12 and to prevent deterioration in image quality.

  Further, as described above, when the document is fed, the pickup roller 31 rotates around the shaft 45 and contacts the end portion of the document set on the document tray 23. The impact at the time is particularly great among the vibrations generated when the document is conveyed. In this respect, in the present embodiment, the inner guide 19 is disposed so as to face the pickup roller 31 as described above, and the impact caused by the rotation is received by the inner guide 19. Thereby, it is possible to prevent a strong impact due to the retraction operation of the pickup roller 31 from being transmitted directly to the scanner frame 12 and to prevent deterioration of the image quality.

  Further, a plurality of the separation preventing portions 172 to 175 are formed, and each is paired. Specifically, the two separation preventing portions 172 and 173 are disposed substantially symmetrically so as to form a pair relationship on the front side and the back side (one end side and the other end side in the document width direction), respectively. The same applies to the two separation preventing portions 174 and 175. Since the separation preventing portions 172 to 175 are provided as a pair in this way, the scanner frame 12 is allowed to tilt with respect to the inner guide 19 within an angle range normally required for positioning. Can be prevented from tilting excessively.

  Further, as described above, the inner guide 19 is made of resin and is configured to be elastically deformed to some extent. Therefore, in a state where the scanner frame 12 is rotated to the open position in FIG. 3, the operator manually deforms the inner guide 19 to remove the claw portions 122 to 125, thereby removing the scanner frame 12 from the ADF 25. be able to. As described above, since the scanner frame 12 can be easily removed without using a tool or the like, maintenance such as cleaning of the second scanner unit 60 or replacement of parts is facilitated.

  As described above, the image scanner device 10 of the present embodiment includes the ADF 25, and can read both sides of a document conveyed by the ADF 25 in one pass. The ADF 25 of this embodiment is configured as follows. That is, the ADF 25 includes a document transport path 30 for transporting a document, a second scanner unit 60, an inner guide (support member) 19, and a spring (elastic member) 18. The second scanner unit 60 includes a scanner frame 12 that holds optical components therein, and reads a document that is transported through the document transport path 30. The inner guide 19 is attached to the scanner frame 12, covers at least a part of the outside of the scanner frame 12, and supports the scanner frame 12. The spring 18 is disposed between the scanner frame 12 and the inner guide 19 so as to apply a pressing force in a direction in which the scanner frame 12 and the inner guide 19 are separated.

  That is, the second scanner unit 60 disposed in the ADF 25 provided in the image scanner device 10 capable of reading both sides of the document with one pass is exposed to vibration during document transportation. In this regard, with the above configuration, even if the inner guide 19 vibrates, the vibration is buffered by the spring 18, so that the vibration transmitted to the scanner frame 12 can be reduced. Therefore, it is possible to prevent the reading quality of the document from being deteriorated due to vibration.

  In the ADF 25 of the present embodiment, the second scanner unit 60 is a reading unit of a reduction optical system.

  This makes it possible to exhibit the advantages of the reading unit of the reduction optical system, in which the reading accuracy is higher and the reading speed is higher than that of the reading unit of the contact optical system, while compensating for the disadvantage of the reduction optical system that is weak against vibration. Accordingly, it is possible to provide an automatic document feeder that realizes high reading quality.

  Further, in the ADF 25 of the present embodiment, the separation preventing portions 172 to 175 prevent the scanner frame 12 and the inner guide 19 from being separated by the pressing force of the spring 18.

  Thereby, it is possible to prevent the scanner frame 12 and the inner guide 19 from being detached, and to appropriately exhibit the vibration buffering effect by the spring 18.

  Further, in the ADF 25 of the present embodiment, the separation preventing units 172 to 175 are provided in pairs.

  As a result, the detachment preventing portions 172 to 175 can prevent the posture of the scanner frame 12 from being excessively inclined with respect to the inner guide 19.

  Further, in the ADF 25 of the present embodiment, the separation preventing portions 172 to 175 are formed so as to be able to contact the claw portions 122 to 125 formed on the scanner frame 12 and the claw portions 122 to 125 in the inner guide 19, respectively. Contact surfaces 192 to 195.

  Thereby, the effect of preventing separation of the inner guide 19 and the scanner frame 12 can be obtained with a simple configuration. Further, since the inner guide 19 and the scanner frame 12 can be detached without using a special tool or the like, maintenance work is facilitated.

  In the ADF 25 of the present embodiment, the inner guide 19 is formed with a guide portion 17 that constitutes a part of the document transport path 30 and guides the document transport.

  As a result, the inner guide 19 has both the role of supporting the scanner frame 12 and the role of guiding the document, so that the apparatus can be configured compactly, and the number of parts can be reduced to reduce the cost. Further, since the inner guide 19 guides the conveyance of the document, the vibration generated by the conveyance of the document can be weakened by the buffering action of the spring 18. As a result, it is possible to prevent the reading quality from being deteriorated due to the vibration caused by the conveyance of the document.

  In the ADF 25 of the present embodiment, the scanner frame 12 and the inner guide 19 are configured to be detachable.

  That is, the inner guide 19 and the scanner frame 12 are detachable, and the scanner frame 12 is supported by the inner guide 19. Accordingly, the second scanner unit 60 can be easily detached by removing the scanner frame 12 from the inner guide 19 during maintenance or the like. Therefore, maintainability is improved.

  In the ADF 25 of the present embodiment, the scanner frame 12 includes a positioning unit 59 that positions the second scanner unit 60.

  Thereby, the second scanner unit 60 can be accurately positioned at the reading position of the document while suppressing the influence of the vibration of the inner guide 19 by the spring 18, so that the reading quality can be improved.

  Although the preferred embodiment of the present invention has been described above, the above configuration can be changed as follows, for example.

  In the above-described embodiment, the configuration in which the scanner frame 12 is pressed downward from the inner guide 19 by the spring 18 is shown, but the configuration in which the scanner frame 12 is pressed upward from the inner guide 19 instead of or in addition to this. Can be changed. For example, in addition to the spring 18 described above, another spring (for example, a compression coil spring) can be disposed between the claw portion 124 and the contact surface 194 and between the claw portion 125 and the contact surface 195, respectively. . This another spring is arranged so as to separate the scanner frame 12 and the inner guide 19. With this configuration, the scanner frame 12 is pressed downward by the spring 18 and is pressed upward by the another spring. As described above, even when the scanner frame 12 is configured to be pressed in the vertical direction by the spring (elastic member), the vibration transmitted to the scanner frame 12 can be reduced by the buffering effect of the spring as in the above embodiment.

  As the elastic member, an appropriate elastic member such as a leaf spring can be used instead of the spring 18 which is a compression coil spring.

  The claw portion may be formed on the inner guide 19 side instead of the configuration formed on the scanner frame 12 side. In this case, by forming a contact surface (contact portion) on the scanner frame 12 side, the same effect as in the above embodiment can be obtained.

  The number, position, and the like at which the claw portion and the contact portion are formed are arbitrary, and can be formed at an appropriate position by an appropriate number. Moreover, the shape of a nail | claw part and a contact part is not restricted to said structure, If it is a shape which can achieve the effect of this invention, it can form in arbitrary shapes.

  In addition, the separation preventing portion can be changed to a configuration in which, for example, a screw is used instead of the configuration in which the claw portion and the contact portion are used as described above. However, from the standpoint of enabling the inner guide 19 and the scanner frame 12 to move relative to each other with a simple configuration and improving the maintainability by facilitating the removal of the scanner frame 12, the claw portion and the contact portion as described above. It is preferable that it is comprised by.

  The support member may not be configured as a guide portion that guides the document. For example, the document may be guided by a member independent of the scanner frame and the support member. According to this, it is possible to further prevent the vibration due to the conveyance of the document from being transmitted to the scanner frame. However, since the apparatus becomes larger in the vertical direction by providing another member, it is preferable that the support member also serves as the guide portion from the viewpoint of making the apparatus compact.

  The present invention can be applied not only to a reading unit of a reduction optical system but also to a reading unit of a contact optical system. However, since the reading unit of the reduction optical system is easily affected by vibration, it is particularly preferable to apply the present invention.

  The image scanner device 10 of the present invention can be applied to, for example, a copy machine, a facsimile machine, etc. instead of the copy facsimile multifunction machine 20.

  In the above embodiment, the image scanner device 10 is provided as a part of the multi-function device 20, but instead of this configuration, it can be configured as a single image scanner device.

1 is an external perspective view showing a state of a copy facsimile multifunction peripheral including an automatic document feeder and an image scanner according to an embodiment of the present invention. FIG. 2 is a front cross-sectional view illustrating configurations of an automatic document feeder and an image scanner device according to the present embodiment. FIG. 6 is a front sectional view showing a state when the second scanner unit and the inner guide are rotated. The external appearance perspective view which showed the schematic structure of the 2nd scanner unit and the inner guide. Front sectional drawing of a 2nd scanner unit and an inner guide. Side surface sectional drawing of a 2nd scanner unit and an inner guide.

Explanation of symbols

10 Image scanner device (document reading device)
12 Scanner frame (frame)
17 Guide part 18 Spring (elastic member)
19 Inner guide (support member)
25 ADF (Automatic Document Feeder)
31 Pickup roller (feeding part)
59 Positioning unit 60 Second scanner unit (reading unit)
90 Second document reading position (document reading position)
122, 123, 124, 125 Claw part 172, 173, 174, 175 Detachment prevention part 192, 193, 194, 195 Contact surface (contact part)

Claims (10)

A document transport path for transporting the document;
A reading unit that includes a frame that holds an optical component therein, and that reads a document conveyed through the document conveyance path;
A support member attached to the frame, covering at least a part of the outside of the frame, and supporting the frame;
An elastic member disposed between the frame and the support member so as to apply a pressing force in a direction to separate the frame and the support member;
An automatic document feeder characterized by comprising: The automatic document feeder according to claim 1,
An automatic document feeder, wherein the reading unit is a reading unit of a reduction optical system. The automatic document feeder according to claim 1 or 2,
An automatic document feeder comprising a separation preventing portion for preventing separation of the frame and the support member due to a pressing force of the elastic member. The automatic document feeder according to claim 3,
2. The automatic document feeder according to claim 1, wherein the separation preventing unit is provided in pairs. The automatic document feeder according to claim 3 or 4,
The separation prevention unit is
Claw portions formed on one of the frame and the support member;
On the other hand, a contact portion that is formed at a position corresponding to the claw portion and is capable of contacting the claw portion;
An automatic document feeder characterized by comprising: An automatic document feeder according to any one of claims 1 to 5,
An automatic document conveying apparatus, wherein the supporting member is formed with a guide portion that constitutes a part of the document conveying path and guides conveyance of the document. An automatic document feeder according to any one of claims 1 to 6,
An automatic document feeder, wherein the frame and the support member are detachable. An automatic document feeder according to any one of claims 1 to 7,
The automatic document feeder according to claim 1, wherein the frame includes a positioning portion for positioning the reading unit.   An original document reading apparatus comprising the automatic document feeder according to any one of claims 1 to 8. The document reading device according to claim 9,
An original reading apparatus capable of reading both sides of an original conveyed by the automatic original conveying apparatus in one pass.

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