JP5024677B2 - Automatic document feeder and document reader - Google Patents

Description

  The present invention relates to an automatic document feeder and a document reading apparatus including the automatic document feeder. More specifically, the present invention relates to a configuration for pressing a roller shaft arranged in the vicinity of a reading unit of a reduction optical system provided in the automatic document feeder and the document reading device.

  2. Description of the Related Art Conventionally, there has been known an original reading apparatus provided with an automatic original conveying apparatus (auto document feeder, ADF) capable of conveying an original along a predetermined curved original conveying path and reading both sides of the original. . In this type of ADF, a reading unit may be arranged inside the document transport path.

A document reading apparatus provided with the above ADF is disclosed in, for example, Patent Document 1. In the document reading device described in Patent Document 1, a reading unit (first reading unit) including a contact image sensor is arranged inside an ADF unit, and one side of a document can be read by the reading unit. . A plurality of transport rollers are provided in the vicinity of the reading unit.
Japanese Patent Laid-Open No. 10-126659

  The ADF configured as disclosed in Patent Document 1 may have a configuration in which a contact roller (nip roller) for pressing and nipping a document passing near the reading unit is provided on the reading unit side. The contact roller needs to be urged with a sufficient pressing force to nip the original.

  By the way, as a document reading method, two methods called a reduction optical system and a contact optical system are known. In general, the reduction optical system reading method is advantageous in terms of image quality because of its deep depth of field, and therefore, for example, a reduction optical system is often used in a higher-level document reader. ing.

  On the other hand, a reduction optical system reader needs to include a plurality of mirrors, a condensing lens, and optical components such as a CCD in order to ensure a sufficient optical path length. Normally, these optical components are attached to a frame. However, when the frame is distorted by an external force, the optical axis of the optical component is also distorted, leading to a decrease in image quality.

  When the ADF including the reduction optical system reading unit is provided with the contact roller, a load (pressing reaction force) applied to the contact roller is applied to the frame, and the frame is distorted. This distortion of the frame hardly causes a problem in the reading unit of the close-contact optical system as shown in Patent Document 1, but causes the deterioration of the image quality as described above in the reading unit of the reduction optical system.

  The present invention has been made in view of the above circumstances, and a main object thereof is to provide an automatic document feeder in which the optical axis does not shift due to a load from a roller.

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, a reduction optical system reading unit, and a support member. The document transport path is configured to be curved in order to transport a document. The reading unit of the reduction optical system is disposed inside the document conveyance path. The reading unit includes a frame that supports an internal optical component, a roller shaft is disposed so as to have play with respect to the frame, and a contact roller that can contact the document is supported by the roller shaft. is there. The support member will covering at least a portion of an outer side of the reading unit. The support member includes an elastic member for pressing the roller shaft in a direction in which the contact roller is pressed against a document passing through the document conveyance path, and an elastic member mounting portion to which the elastic member is mounted. The support member is supported by a support shaft. The frame is attached to the support member so that the frame can rotate about the support shaft together with the support member. The frame includes a positioning unit for positioning the frame at a position where the document can be read. And when the said frame is positioned by the said positioning part, it will be in the state which floated from the said supporting member.

  Thereby, the support member receives a load applied to the contact roller when the document is conveyed, and a configuration in which no load is applied to the frame side can be realized. Accordingly, it is possible to prevent the frame from being distorted by the load from the contact roller and the optical axis of the internal optical component from being displaced. As a result, it is possible to provide an automatic document feeder that realizes a good reading accuracy because the optical axis is hardly displaced even though it is a reduction optical system.

  In the automatic document feeder, it is preferable that the support member is a guide member that constitutes a part of the document conveyance path and guides the document to be conveyed.

  As a result, the document being conveyed can be guided and smoothly fed. Further, since the support member also serves as a guide member, the configuration of the apparatus can be simplified.

  In the automatic document feeder, the support member includes a roller shaft support portion that can be supported by contacting a part of the roller shaft in order to prevent the roller shaft from being pulled out by being pressed by the elastic member. It is preferable to provide.

  Thereby, it is possible to prevent the roller shaft from coming off due to the pressing force of the elastic member. Further, since the support member includes the roller shaft support portion, it is possible to prevent the pressing force of the elastic member from being applied to the frame side. For this reason, it can prevent that the optical axis of the optical component inside a flame | frame shifts | deviates.

  In the automatic document feeder, it is preferable that the elastic member and the elastic member mounting portion are disposed outside the frame.

  Thereby, an elastic member, an elastic member attaching part, a support member, and a frame can be rationally arranged without interfering with each other. Further, since the elastic member can be arranged so as not to disturb the optical axis of the reading unit, the reading unit can be downsized.

  In the automatic document feeder, it is preferable that at least both ends of the roller shaft are pressed by the elastic member.

  Thereby, a roller axis | shaft can be pressed uniformly with sufficient balance.

  In the automatic document feeder, it is preferable that the frame includes a restricting member that restricts the contact roller from moving in the axial direction of the roller shaft.

  Thereby, it is possible to prevent the contact roller from being displaced in the axial direction. In addition, since almost no load is applied in the axial direction of the roller shaft, the frame will not be distorted by the load from the contact roller even if a regulating member is provided on the frame side. Further, since the movement of the contact roller is restricted by the restriction member provided in the frame on which the roller shaft is disposed, the reading unit can be configured compactly.

  In the automatic document feeder, it is preferable that the support member is formed with a rotation preventing portion that restricts rotation of the roller shaft.

  Thereby, since it can prevent that a roller axis | shaft rotates, a roller axis | shaft can be favorably pressed by an elastic member.

  In the automatic document feeder, it is preferable that the contact roller is disposed downstream of the document reading position of the reading unit in the document conveying direction.

  Thereby, the original conveyed to the downstream side of the original reading position of the reading unit can be conveyed by the contact roller.

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

  As a result, it is possible to provide a reduction optical system document reading apparatus that is less likely to cause optical axis misalignment and has high reading accuracy.

  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 equipped with an automatic document feeder 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 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. Yes.

  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 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.

  With this configuration, when the pickup roller 31 is driven, the uppermost document on the document tray 23 is fed into the ADF 25. 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. 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 and a counter roller that is paired with the registration roller 39 are arranged. 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 after a predetermined time, conveys it downstream while removing the slack. 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 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. As described above, the scanner frame 12 is held in the ADF 25. A contact roller 40 is disposed at the bottom of the scanner frame 12 and downstream of the reading glass 42. The contact roller 40 is rotatably supported by a roller shaft 46 and is disposed 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.

  A concave portion 58 for arranging the contact roller 40 and the roller shaft 46 is formed in an elongated shape in the axial direction of the roller shaft 46 at the bottom of the scanner frame 12. The scanner frame 12 is provided with a path guide (regulating member) 45 for guiding the document while covering the recess 58 so that the document being conveyed is not caught in the recess 58. The recess 58 is formed so as to have sufficient play with respect to the roller shaft 46, and is configured so that the roller shaft 46 does not contact the scanner frame 12 main body and the path guide 45 during document conveyance. Yes.

  Further, an inner guide 19 that constitutes a part of the curved document transport path 30 and guides the direction of the document is attached to the scanner frame 12 provided in the second scanner unit 60. The inner guide 19 is disposed in a range from the pickup roller 31 to the registration roller 39 in the document conveyance path 30. The inner guide 19 is disposed below the pickup roller 31 and the separation roller 32 and is supported by the support shaft 41 of the registration roller 39.

  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, a so-called one-pass ADF 25 is configured, which allows double-sided reading by allowing a document to pass through the document transport path 30 only 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 below.

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

  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 the original is jammed, the original can be removed by rotating the second scanner unit 60 upward to open the original conveyance path 30. As a result, maintainability is improved.

  This will be specifically described below. That is, the scanner frame 12 is positioned inside the document conveyance path 30 as shown in FIG. 2 in a normal state, and is in a substantially horizontal posture. 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.

  As shown in FIG. 4, the second scanner unit 60 includes a plurality of contact rollers 40 arranged in the width direction of the document (the axial direction of the roller shaft 46). In the present specification, the “document width direction” means a direction orthogonal to the document thickness direction and orthogonal to the document conveyance direction. As described above, the contact roller 40 is rotatably supported by the roller shaft 46. A path guide 45 is provided so as to cover the roller shaft 46.

  A cutout 451 is formed in the path guide 45 at a position corresponding to the position where the contact roller 40 is disposed. The width of the notch 451 is slightly larger than the width of the contact roller 40, and a part of the surface of the contact roller 40 is exposed from the notch 451 to the bottom of the second scanner unit 60. With this configuration, the contact roller 40 can be prevented from being displaced in the axial direction of the roller shaft 46 by the notch 451. Therefore, it can be said that the path guide 45 functions as a regulating member that regulates the position of the contact roller 40.

  Next, the support structure of the roller shaft 46 will be described with reference to FIG. FIG. 5 is a schematic longitudinal sectional view of the second scanner unit 60 and the inner guide 19.

  As shown in FIG. 5, the inner guide 19 extends downward from the horizontal portion 196 that covers the upper side of the scanner frame 12 and from both ends of the horizontal portion 196 in the document width direction (end portions on the front side and the back side of the apparatus). And a vertical portion 197. The vertical portion 197 is formed so as to cover only a part of both sides of the scanner frame 12 in the document width direction. Further, both ends of the roller shaft 46 in the longitudinal direction are inserted from the inside in the vicinity of the lower end of the vertical portion 197, respectively.

  A spring mounting portion (elastic member mounting portion) 191 and a roller shaft support portion 192 are formed in each vertical portion 197 of the inner guide 19. In addition, a scanner frame support surface 193 is formed on the vertical portion 197 at an appropriate position.

  The scanner frame 12 has a protrusion 121 at a position corresponding to the scanner frame support surface 193. The projection 121 is configured to project outward from the scanner frame 12 in the document width direction (the front side and the back side of the apparatus). The projection 121 comes into contact with the scanner frame support surface 193 so that the scanner frame 12 It can be supported inside the guide 19. However, when the scanner frame 12 is positioned by the positioning portion 59, the protrusion 121 is slightly lifted from the scanner frame support surface 193 as shown in FIG.

  The spring attachment portion 191 is configured to be able to attach a spring 18 as an elastic member. Specifically, the spring 18 is configured as a compression coil spring, and the spring mounting portion 191 is formed as a columnar protrusion protruding in the axial direction of the spring 18 so as to be inserted into the spring 18. . Thereby, the spring 18 can be held at a predetermined position and in a predetermined direction.

  The spring 18 held by the spring mounting portion 191 is configured to press both ends of the roller shaft 46 downward. Thereby, the contact roller 40 can be urged with a predetermined pressing force. Accordingly, the original can be held between the contact roller 40 and the discharge roller 36 with a predetermined nip force, and the original can be reliably discharged to the discharge tray 24 by driving the discharge roller 36.

  With the configuration as described above, the pressing reaction force from the discharge roller 36 is applied upward to the contact roller 40, and almost all of this upward load is received by the spring mounting portion 191 via the spring 18. It is done. That is, all the upward load from the contact roller 40 is applied to the inner guide 19, and no load is applied to the scanner frame 12. Thereby, it becomes possible to suppress the distortion of the scanner frame 12 due to the load from the contact roller 40 side, and it is possible to maintain high document reading accuracy.

  The roller shaft support portion 192 is formed at a position facing the spring mounting portion 191, and is configured to be able to support the roller shaft 46 by contacting the end portion of the roller shaft 46. . With this configuration, at the time of normal reading, the roller shaft 46 resists the pressing force of the spring 18 by the upward load (pressing reaction force) applied from the discharge roller 36 to the contact roller 40, and the roller shaft support portion 192. It is in a state of floating from. On the other hand, in the open position shown in FIG. 3, the contact between the contact roller 40 and the discharge roller 36 is released, so that no pressing reaction force is applied to the discharge roller 36, and the roller shaft 46 is pressed by the spring 18. To move away from the scanner frame 12. However, since both ends of the roller shaft 46 are received by the roller shaft support portion 192, the roller shaft 46 can be prevented from being detached from the scanner frame 12. In addition, since the roller shaft support portion 192 is formed on the inner guide 19 side, the pressing force of the spring 18 is not applied to the scanner frame 12, so that the scanner frame 12 can be prevented from being distorted.

  Next, a configuration in the vicinity of the roller shaft support portion 192 will be described in detail with reference to FIG. FIG. 6 is a front sectional view of an essential part of the inner guide 19.

  As described above, since the plurality of contact rollers 40 are supported so as to be rotatable relative to the roller shaft 46, the roller shaft 46 itself does not need to rotate. In consideration of this point, in the present embodiment, as shown in FIG. 6, the end of the roller shaft 46 is notched in a flat shape to form a notch 461, and the cross section thereof is formed in a D-shape. Yes. The roller shaft support portion 192 is formed with a rotation preventing portion 194. The rotation preventing portion 194 contacts the surface of the notch 461 so that the rotation of the roller shaft 46 can be prevented. By thus supporting the roller shaft 46 so as not to rotate, the roller shaft 46 can be stably pressed by the spring 18. Further, it is possible to prevent abnormal noise from being generated at the contact portion between the roller shaft 46 and the spring 18 and to improve the quietness.

  As described above, the ADF 25 included in the image scanner device 10 of the present embodiment includes the document conveyance path 30, the second scanner unit 60 of the reduction optical system, and the inner guide 19. The document transport path 30 is configured to be curved in order to transport a document. The second scanner unit 60 is disposed inside the document conveyance path 30. The second scanner unit 60 includes a scanner frame 12 that supports internal optical components, a roller shaft 46 is disposed so as to have play with respect to the scanner frame 12, and the contact roller 40 that can contact the document is the roller. The structure is supported by the shaft 46. The inner guide 19 covers a part of the outside of the second scanner unit 60 and supports the second scanner unit 60. The inner guide 19 includes a spring 18 for pressing the roller shaft 46 in a direction in which the contact roller 40 is pressed against the document passing through the document conveyance path 30 and a spring mounting portion 191 to which the spring 18 is attached.

  Thereby, the inner guide 19 receives a load applied to the contact roller 40 when the document is conveyed, and a configuration in which no load is applied to the scanner frame 12 can be realized. Therefore, it is possible to prevent the scanner frame 12 from being distorted by the load from the contact roller 40 and the optical axis of the internal optical component from being displaced. As a result, it is possible to provide the ADF 25 that realizes good reading accuracy because the optical axis is hardly displaced even though it is a reduction optical system.

  In the ADF 25 of the present embodiment, the inner guide 19 constitutes a part of the document conveyance path 30 and is configured as a guide member that guides the document to be conveyed.

  As a result, the document being conveyed can be guided and smoothly fed. Further, the inner guide 19 serves both as a member for pressing the roller shaft 46 and as a guide member, whereby the configuration of the apparatus can be simplified.

  In the ADF 25 of the present embodiment, the inner guide 19 is a roller shaft support portion 192 that can be supported by contacting a part of the roller shaft 46 in order to prevent the roller shaft 46 pressed by the spring 18 from coming off. It has.

  Thereby, it is possible to prevent the roller shaft 46 from coming off due to the pressing force of the spring 18. Further, since the inner guide 19 includes the roller shaft support portion 192, it is possible to prevent the pressing force of the spring 18 from being applied to the scanner frame 12 side. For this reason, it is possible to prevent the optical axes of the optical components inside the scanner frame 12 from being displaced.

  Further, in the ADF 25 of the present embodiment, the spring 18 and the spring mounting portion 191 are arranged outside the scanner frame 12.

  Thereby, the spring 18, the spring mounting portion 191, the inner guide 19, and the scanner frame 12 can be rationally arranged without interfering with each other. Further, since the spring 18 can be disposed so as not to disturb the optical axis of the second scanner unit 60, the second scanner unit 60 can be reduced in size.

  Further, in the ADF 25 of this embodiment, both ends of the roller shaft 46 are pressed by the spring 18.

  Thereby, the roller shaft 46 can be pressed evenly with good balance.

  In the ADF 25 of the present embodiment, the scanner frame 12 includes a path guide 45 that restricts the contact roller 40 from moving in the axial direction of the roller shaft 46.

  Thereby, it is possible to prevent the contact roller 40 from being displaced in the axial direction. Further, since almost no load is applied in the axial direction of the roller shaft 46, the scanner frame 12 is not distorted by the load from the contact roller 40 even if a restricting member is provided on the scanner frame 12 side. Further, since the movement of the contact roller 40 is restricted by the restriction member provided in the scanner frame 12 on which the roller shaft 46 is disposed, the second scanner unit 60 can be configured compactly.

  Further, in the ADF 25 of the present embodiment, the inner guide 19 is formed with a rotation preventing portion 194 that restricts the rotation of the roller shaft 46.

  Thereby, since it can prevent that the roller axis | shaft 46 rotates, it can press favorably with the spring 18. FIG.

  Further, in the ADF 25 of the present embodiment, the contact roller 40 is disposed downstream of the second document reading position 90 of the second scanner unit 60 in the document conveyance direction.

  As a result, the original conveyed to the downstream side of the second original reading position 90 of the second scanner unit 60 can be conveyed by the contact roller 40.

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

  As a method of fixing the scanner frame 12 to the inner guide 19, an appropriate method such as screwing can be used in addition to the above configuration.

  As an elastic member, it replaces with the structure which uses the spring 18 which is a compression coil spring as mentioned above, For example, suitable elastic members, such as a leaf | plate spring, can be used.

  In the above configuration, the support member is configured as the inner guide 19 that configures the document conveyance path, but is not limited thereto. That is, it is sufficient that the load from the roller shaft 46 is received by a member different from the scanner frame 12, and it is not always necessary to receive the load by a member constituting the document transport path. Therefore, instead of the configuration in which the support member (inner guide 19) is configured as a cover that covers the scanner frame 12 over a wide range and guides the document as described above, the support member is provided only on the side surface of the scanner frame 12, for example. Can be changed to configuration.

  The configuration for preventing the rotation of the roller shaft 46 is not limited to the above configuration. For example, it can change to the structure fixed by tightening the edge part of the roller shaft 46 with a screw | thread.

  The spring mounting portion 191 can be constituted by, for example, a columnar cross rib instead of a columnar protrusion. Further, the spring mounting portion 191 can be changed to, for example, a circular concave portion into which the spring 18 can be inserted.

  For example, the image scanner device 10 of the present invention can be applied to a copy machine, a facsimile machine, and the like, 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 copy facsimile multifunction machine including an automatic document feeder and an image scanner according to an embodiment of the present invention. 1 is a front cross-sectional view illustrating configurations of an automatic document feeder and an image scanner according to an 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. The typical longitudinal section of the 2nd scanner unit and an inner guide. The front sectional view which expanded the neighborhood of a roller axis support part.

Explanation of symbols

10 Image scanner device (document reading device)
12 Scanner frame (frame)
18 Spring (elastic member)
19 Inner guide (support member)
25 ADF (Automatic Document Feeder)
40 Contact roller 45 Path guide (regulating member)
46 Roller shaft 60 Second scanner unit (reading unit)
90 Second document reading position (document reading position)
191 Spring mounting part (elastic member mounting part)
192 Roller shaft support part 194 Non-rotating part

Claims (9)

A curved document transport path for transporting a document;
The document transport path having a frame for supporting an internal optical component, a roller shaft disposed so as to have play with respect to the frame, and a contact roller capable of contacting the document supported by the roller shaft A reading unit of a reduction optical system disposed inside
Covers at least a portion of an outer side of the reading unit, prior to SL and the elastic member for pressing the roller shaft the contact roller in a direction to press the document passing through the document conveying path, an elastic member attached to the elastic member is attached part have a, a support member supporting configurations to support shaft,
Equipped with a,
The frame is
It is attached to the support member so that it can rotate around the support shaft together with the support member,
A positioning unit for positioning the frame at a position where the document can be read;
An automatic document feeder, wherein the automatic document feeder is in a state of being lifted from the support member when positioned by the positioning unit. The automatic document feeder according to claim 1,
The automatic document feeder, wherein the support member is a guide member that forms part of the document feeding path and guides the document to be fed. The automatic document feeder according to claim 1 or 2,
The automatic support member includes a roller shaft support portion that can be supported by contacting a part of the roller shaft in order to prevent the roller shaft from being pulled out by being pressed by the elastic member. Document transport device. An automatic document feeder according to any one of claims 1 to 3,
The automatic document feeder, wherein the elastic member and the elastic member mounting portion are arranged outside the frame. An automatic document feeder according to any one of claims 1 to 4,
An automatic document feeder, wherein at least both ends of the roller shaft are pressed by the elastic member. An automatic document feeder according to any one of claims 1 to 5,
The automatic document feeder according to claim 1, wherein the frame includes a restricting member that restricts the contact roller from moving in the axial direction of the roller shaft. An automatic document feeder according to any one of claims 1 to 6,
The automatic document feeder according to claim 1, wherein the support member is formed with a rotation preventing portion for restricting rotation of the roller shaft. An automatic document feeder according to any one of claims 1 to 7,
The automatic document feeder, wherein the contact roller is disposed downstream of the document reading position of the reading unit in the document conveying direction.   An original document reading apparatus comprising the automatic document feeder according to any one of claims 1 to 8.

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