JP2009118413A - Original reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an original reading apparatus capable of preventing shock on a reading section when an openable reading section is closed. <P>SOLUTION: The original reading apparatus includes: an original conveying passage for conveying an original; a scanner unit disposed on the original conveying passage to read a first surface of an original; and a second scanner unit 60 of a reduction optical system to be disposed on the original conveying passage to read a second surface of an original. The original reading apparatus is also provided with a rear surface scanner frame 12 for retaining the second scanner unit 60. The image reading apparatus includes an opening/closing mechanism and the rear surface scanner frame 12 can rotate between a usage position in reading an original and an exposure position at which a reading portion of the second scanner unit 60 is exposed, with the opening/closing mechanism. The original reading apparatus is further provided with a braking member 14. The braking member 14 contacts the rear surface scanner frame 12 when the rear surface scanner frame 12 is rotated to the usage position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a document reading apparatus, and more particularly to a document reading apparatus having a double-sided reading function.

  2. Description of the Related Art Conventionally, there is known a document reading apparatus that includes a reading unit for reading a front surface and a reading unit for reading a back surface, and has a double-sided reading function that can read both sides of a document at once. In such a document reading apparatus, the first reading unit may be configured by a reduction optical system using an image sensor such as a CCD, and the second reading unit may also be configured by a reduction optical system such as a CCD.

Patent Document 1 discloses a document reading apparatus in which both a first reading unit and a second reading unit are configured by a reduction optical system. The document reading device disclosed in Patent Document 1 has been transported by a document feeding unit that transports a document along a document transport path, a first image reading unit that reads an image on the first surface of the transported document, and the like. Second image reading means for reading an image on the second side of the document. The first and second image reading means are image reading means of a reduction optical system including a light source, a mirror, a lens, and an image sensor. With this configuration, the second image reading unit is unitized so that the light source, the mirror, the lens, and the image sensor form one assembly, and is detachably mounted as one unit on the document feeding unit.
JP 2006-253914 A

  When the original is read by the original reading device, the original may be jammed inside the automatic document feeder. In this case, it is necessary to remove the jammed original. In addition, it is necessary to periodically clean the inside in order to prevent proper reading from being prevented from being carried out due to dust such as paper dust and dust on the conveyed document adhering to the reading portion of the reading unit.

  In this regard, in a double-sided reading type image reading apparatus such as Patent Document 1, it is often difficult to remove and clean a jammed document because the second image reading unit is in the way. In the configuration of Patent Document 1, it is possible to remove the second image reading unit from the original conveying apparatus as a unit, but an operation such as removing a screw is necessary, and there is room for improvement from the viewpoint of maintenance efficiency. there were.

  Here, as one method for solving the above-described problem, it is conceivable to provide an automatic document feeder with an opening / closing mechanism. For example, the second reading unit is held by a holding member such as a frame, and the frame can be rotated. According to this configuration, by opening and closing the entire reading unit together with the frame by the opening / closing mechanism, the inside of the apparatus can be accessed, and the jammed document can be easily removed and cleaned.

  However, in the case of a document reading apparatus provided with such an opening / closing mechanism, although maintenance becomes easy, it is conceivable that the user closes the frame with a strong momentum when returning the reading unit to the original position after maintenance. Further, in the case of performing maintenance by opening the frame upward, when the maintenance is completed and the frame is closed, the frame further increases the downward force due to gravity.

  If the frame is returned vigorously and collides with the main body, a large impact is generated on the reading unit attached to the frame. Due to this impact, there is a possibility that the mirror, CCD, and the like constituting the reading unit are displaced from the normal position, and reading cannot be appropriately performed. Although it is conceivable to provide a damper or the like to prevent an impact when closing the holding member, installation of the damper is costly.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a document reading apparatus capable of easily maintaining the periphery of a reading unit and preventing an impact on the reading unit.

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 a first aspect of the present invention, a document reading apparatus having the following configuration is provided. That is, the document reading apparatus includes a document transport path for transporting a document, a first reading unit for reading the first surface of the document, and a reduction optical system for reading the second surface of the document. A second reading unit. The document reading device includes a frame, an opening / closing mechanism, and a brake member. The frame holds the second reading unit. The opening / closing mechanism rotates the frame between a use position for reading a document and an exposure position at which a reading portion of the second reading unit is exposed. The brake member is arranged to contact the frame when the frame is rotated to the use position.

  In this specification, “contact with the frame” includes not only the case where the brake member directly contacts the frame but also the case where the brake member contacts another part fixed to the frame.

  Thereby, even when the frame is pivoted vigorously from the exposure position to the use position, the brake member comes into contact with the frame and the frictional resistance acts, so that the pivoting momentum can be weakened. Therefore, since the shock generated when the frame reaches the use position can be buffered, it is possible to prevent the components constituting the reduction optical system of the second reading unit from being displaced and cannot be read accurately, thereby improving maintainability. . In addition, the cost can be reduced because of the simple configuration in which the brake member is arranged.

  The document reading apparatus preferably has the following configuration. That is, the document reading apparatus has an elongated contact portion that protrudes from an end portion of the frame. And the said brake member is arrange | positioned so that this contact part may be contacted.

  Thereby, the structure for shock buffering can be arranged in a compact space. Moreover, the frictional force generated when the frame is rotated can be easily controlled by appropriately setting the contour of the contact portion.

  In the document reading apparatus, it is preferable that the contact portion is separated from the brake member when the frame is in the use position.

  Thereby, since a frictional force does not generate | occur | produce when positioning a flame | frame to a use position, positioning can be performed smoothly. Therefore, the reading position by the second reading unit can be accurately adjusted to a predetermined position, and reading can be performed appropriately.

  In the document reading apparatus, it is preferable that the contact portion is configured to be separated from the brake member during a part of the rotation stroke of the frame including the end portion on the use position side. .

  Thereby, since the frictional resistance by the brake member does not work when the frame starts to rotate from the use position, it is possible to prevent the user from feeling caught when the frame is rotated from the use position. Therefore, the frame can be smoothly rotated to the exposure position.

  In the document reading apparatus, it is preferable that the contact portion is separated from the brake member in a part of strokes including the end portion on the exposed position side in the rotation stroke of the frame.

  Thereby, since the frictional resistance by the brake member does not work when the frame starts to rotate from the exposed position, it is possible to prevent the user from feeling caught when the frame is rotated from the exposed position. Therefore, the frame can be smoothly rotated to the use position.

  In the document reading apparatus, it is preferable that the brake member has a roller shape.

  As a result, the frictional force can be gradually increased from the start of contact of the brake member with the frame. Therefore, the frame can be smoothly rotated and the occurrence of an impact can be further suppressed.

  The document reading apparatus preferably has the following configuration. In other words, the document reading apparatus includes a reading roller disposed to face the second reading unit. The brake member is disposed coaxially with the reading roller.

  Thereby, the reading roller and the brake member can be arranged in a compact space. Accordingly, it is possible to reduce the size of the document reading apparatus.

  In the document reading apparatus, it is preferable that the brake member is formed of an elastic member.

  Thereby, an impact can be relieved more effectively by the elasticity with which a brake member is provided.

  The document reading apparatus preferably has the following configuration. That is, the document reading apparatus includes a one-way clutch connected to the brake member. The one-way clutch allows the brake member to rotate when the frame rotates from the use position to the exposed position, and prevents the brake member from rotating in the opposite direction.

  Accordingly, when the frame is rotated from the use position to the exposure position, the brake member rotates according to the rotation of the frame, so that the frame can be opened smoothly. Further, when the frame is rotated from the exposure position to the use position, the brake member is locked in rotation by the one-way clutch, so that frictional resistance acts on the frame. Therefore, the opening / closing operation can be performed efficiently, and the impact generated by the rotation can be prevented.

  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 peripheral (multifunction peripheral) 20 including an image scanner 10 as an original reading apparatus according to an embodiment of the present invention. As shown in FIG. 1, the copy facsimile multifunction machine 20 includes an image scanner device 10 that functions as a book scanner and an auto document feed scanner. The copy facsimile multifunction machine 20 includes an operation panel 77 for instructing the number of copies, a facsimile transmission destination, a document reading, and the like, a main body 78 including an image forming unit for forming an image on a sheet as a recording medium, and the like. A paper feed cassette 79 for sequentially feeding the paper. 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. FIG. 2 is a front sectional view of the image scanner device 10. 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. The image scanner device 10 also includes a scanner unit (first reading unit) 50 and a second scanner unit (second reading 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 document is read by the scanner unit 50, and the image on the back side (second side) 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 scanner unit 50 can read the original image.

  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.

  As shown in FIG. 2, a curved 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 curved 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 omitted in FIG.

  Next, a detailed configuration of each part of the ADF 25 will be described 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. The pickup roller 31 feeds the uppermost document on the document tray 23 and conveys it toward the downstream separation roller 32. The separation roller 32 rotates while nipping the document with the opposing roller 37 to separate the documents one by one and further conveys the document downstream.

  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 document passing through the first document reading position 80 is scanned and read by a scanner unit 50 described below. A platen roller 29 is disposed at the first document reading position 80.

  The scanner unit 50 will be described. The scanner unit 50 is disposed on the main body 78 side, and is disposed below the ADF 25 and the platen glass 22. The 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 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 scanner unit 50 are moved along the platen glass 22. As a result, the document placed on the platen glass 22 can be scanned.

  On the other hand, when the image scanner device 10 is used as an auto document feed scanner (when an original is read using the ADF 25), the light source 51, the reflection mirror 52, and the like are arranged at the first original reading position 80 as shown in FIG. Move to a position opposite to and keep it stationary. By driving the ADF 25 in this state, the 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 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 60 is installed inside the document conveyance path 30 so as to be in contact with the document conveyance path 30 configured in a curved shape. The ADF 25 includes a back scanner frame 12, and the second scanner unit 60 is held in the ADF 25 by the back scanner frame 12. The back scanner frame 12 is configured to cover the second scanner unit 60, and a reading glass 42 for reading the back side of the document is provided at the bottom (portion in contact with the document transport path 30). The reading glass 42 is disposed at a position corresponding to the second document reading position 90.

  The back scanner frame 12 is hermetically sealed, and the components of the second scanner unit 60 are disposed therein. Similar to the scanner unit 50, 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. The light source 61 irradiates the second original reading position 90 with light through the reading glass 42, and the reflected light from the original is reflected by the reflecting mirrors 62, 63, 64, 65 and further converged by the condenser lens 67. The image is formed on the CCD 57 portion. Similar to the CCD 56 in the scanner unit 50, the CCD 57 outputs an electrical signal corresponding to the image information of the document. This signal is also appropriately converted and transmitted to the image forming unit provided in the multifunction machine 20.

  Further, a platen roller (reading roller) 38 is disposed in the ADF 25 main body so as to face the second document reading position 90 of the back 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.

  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 the discharge roller 36 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, a configuration for opening and closing the back scanner frame 12 will be described with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view of the ADF 25 with the cover portion 11 open. FIG. 4 is a cross-sectional perspective view showing a state in which the back scanner frame 12 is opened.

  The ADF 25 includes an ADF main body portion 16 and a cover portion 11 that covers the upper side thereof. The cover part 11 is supported by the ADF main body part 16 via a cover rotation shaft 40. Further, the back scanner frame 12 provided in the ADF 25 is provided with a back scanner rotation shaft 41 for rotating the back scanner frame 12 coaxially with the registration roller 39. The back scanner rotation shaft 41 constitutes a hinge mechanism (open / close mechanism) for opening and closing the back scanner frame 12.

  In order to perform maintenance or the like with the above configuration, first, the cover unit 11 is turned upward to lift the cover unit 11 so that the cover unit 11 is opened as shown in FIG. Next, the back scanner frame 12 in the closed position (use position) is rotated upward to lift. As described above, as shown by the chain line in FIG. 3 or FIG. 4, the reading glass 42 and the like can be exposed by pulling the back scanner frame 12 upward to the open position (exposure position). By rotating the entire second scanner unit 60 in this way, the document conveyance path 30 can be widely exposed, and a large work space for maintenance or the like can be secured.

  As shown in FIG. 4, a brake member 14 is provided at the shaft end of the platen roller 38 on the rear side (right side in FIG. 4). The brake member 14 is formed in a columnar shape, and the diameter thereof is configured to be larger than the diameter of the platen roller 38. The brake member 14 is disposed slightly outside in the width direction with respect to the main body of the back scanner frame 12. Note that the brake member 14 is configured as an elastic member formed of urethane rubber, and is integrally formed with the platen roller 38 in the present embodiment.

  The back scanner frame 12 includes a contact portion 13 that protrudes toward the brake member 14. As shown in FIG. 3 and the like, the contact portion 13 is a circle along the lower edge of the back scanner frame 12 from the end on the first document reading position 80 side of the back scanner frame 12 to the vicinity of the second document reading position 90. It is elongated in an arc shape. In the present embodiment, the contact portion 13 is integrally formed with the back scanner frame 12.

  Next, an operation for rotating the back scanner frame 12 from the exposed position to the use position in FIG. 4 will be described with reference to FIGS. FIG. 5 is a cross-sectional view of the main part showing the positional relationship between the contact portion 13 and the brake member 14 in an exposed state where the back scanner frame 12 is opened. FIG. 6 is a cross-sectional view of the main part showing a state in which the contact portion 13 and the brake member 14 are in contact with each other. FIG. 7 is a cross-sectional view of the main part showing the positional relationship between the contact portion 13 and the brake member 14 in the vicinity of the second document reading position 90.

  When the back scanner frame 12 is set to the exposed position, as shown in FIG. 5, the contact portion 13 and the brake member 14 are in a separated state without contacting each other. In this state, the user performs, for example, maintenance for cleaning the reading glass 42. After the completion of this work, the user pushes the back scanner frame 12 down by hand in order to return to the use position shown in FIG. The back scanner frame 12 rotates downward about the back scanner rotation shaft 41 described above.

  When the back scanner frame 12 rotates downward, the contact portion 13 comes into contact with the brake member 14 as shown in FIG. The brake member 14 is provided so as to rotate integrally with the platen roller 38 as described above. When the ADF 25 is not driven, the brake member 14 (and the platen roller 38) is rotated by a lock mechanism (not shown). Locked not to. Therefore, a frictional resistance against the rotation of the back scanner frame 12 is generated at the contact portion between the contact portion 13 and the brake member 14.

  This frictional force can weaken the momentum at which the back scanner frame 12 is closed. That is, for example, when the user closes the back scanner frame 12 after maintenance work, the back scanner frame 12 may rotate with a strong momentum. In particular, in the configuration in which the use position is lower than the exposure position as shown in FIG. 3, when the back scanner frame 12 is rotated from the exposure position to the use position, it acts on the back scanner frame 12 and the second scanner unit 60. The momentum of rotation is strengthened by the gravity. However, in the configuration of the present embodiment, even in such a case, the brake member 14 comes into contact with the contact portion 13 and frictional resistance acts, so that the rotational speed of the back scanner frame 12 can be reduced.

  When the back scanner frame 12 further rotates downward and reaches just before the use position, the contact portion 13 is separated from the brake member 14 as shown in FIG. 7, and the frictional resistance by the brake member 14 is released. . Thereafter, the second scanner unit 60 is positioned at a predetermined position by the back scanner frame 12 coming into contact with a stopper (not shown). As a result, the back scanner frame 12 returns to the use position. Since the momentum of the back scanner frame 12 is weakened by the frictional resistance, a large impact does not occur when the back scanner frame 12 contacts the stopper.

  Thereafter, by further closing the cover portion 11, the ADF 25 can be used again. When the back scanner frame 12 is in the use position, the contact portion 13 is separated from the brake member 14, so that the platen roller 38 integrally formed with the brake member 14 freely rotates and conveys the document. Can do.

  As described above, the image scanner device (document reading device) 10 provided in the multifunction machine 20 of the present embodiment is configured as follows. That is, the image scanner device 10 includes a document transport path 30 for transporting a document, a scanner unit 50 for reading the front surface (first surface) of the document, and a back surface (second surface) of the document. A second scanner unit 60. The second scanner unit 60 is configured to read image information by a reduction optical system including a light source 61, reflection mirrors 62, 63, 64, 65, a condenser lens 67, and a CCD 57. In addition, the image scanner device 10 includes a back scanner frame 12 that holds the second scanner unit 60, an opening / closing mechanism for the back scanner frame 12, and a brake member 14. The opening / closing mechanism is provided between the use position (the position indicated by the solid line in FIG. 3) when reading the original and the exposed position (the position indicated by the chain line in FIG. 3) where the reading portion of the second scanner unit 60 is exposed. Rotate with. The brake member 14 is disposed so as to contact the back scanner frame 12 when the back scanner frame 12 is rotated to the use position.

  With this configuration, even when the back scanner frame 12 is vigorously rotated from the exposed position to the use position, the brake member 14 contacts the back scanner frame 12 as shown in FIG. Can weaken the momentum. Therefore, an impact generated when the back scanner frame 12 reaches the use position can be buffered. As a result, it is possible to prevent a state in which the reflection mirrors 62, 63, 64, 65 and the CCD 57 constituting the second scanner unit 60 are misaligned and reading cannot be performed accurately, thereby improving maintainability. Moreover, since it is a simple structure provided with the brake member 14, cost can be reduced.

  In the present embodiment, the image scanner device 10 has an elongated contact portion 13 that protrudes from an end portion of the back scanner frame 12. And the brake member 14 is arrange | positioned so that this contact part 13 may be contacted.

  With this configuration, a configuration for shock buffering can be arranged in a compact space. Further, by appropriately setting the contour of the contact portion 13, the strength of the frictional force generated when the back scanner frame 12 is rotated, the rotation stroke section where the frictional force is generated, and the like can be easily controlled.

  In the present embodiment, the contact portion 13 is configured to be separated from the brake member 14 when the back scanner frame 12 is in the use position.

  With this configuration, since the brake member 14 does not come into contact when the back scanner frame 12 is closed, the back scanner frame 12 can be reliably positioned at the use position. Therefore, the reading position by the second scanner unit 60 can be accurately adjusted to a predetermined position, and reading can be performed appropriately.

  Further, in the present embodiment, the contact portion 13 is configured to be separated from the brake member 14 as shown in FIG. 7 in a part of the rotation stroke in the back scanner frame 12 including the end portion on the use position side. Is done.

  With this configuration, since the frictional resistance does not work when the back scanner frame 12 in the use position starts to be opened for maintenance or the like, the user can smoothly expose the back scanner frame 12 to the exposed position without feeling unnecessary catching. Can be rotated.

  Further, in the present embodiment, the contact portion 13 is configured to be separated from the brake member 14 as shown in FIG. 5 in a part of strokes including the end portion on the exposed position side in the rotation stroke of the back scanner frame 12. Is done.

  With this configuration, as shown in FIG. 5, since the frictional resistance by the brake member 14 does not work when the user starts to close the back scanner frame 12 in the exposed position, the user does not feel unnecessary catching. The scanner frame 12 can be smoothly rotated to the use position.

  In the present embodiment, the brake member 14 is configured in a roller shape.

  As described above, since the brake member 14 has a roller shape, the contact of the back scanner frame 12 with the contact portion 13 can be started smoothly. Accordingly, since the frictional resistance can be increased gently, the back scanner frame 12 can be smoothly rotated and the occurrence of impact can be further suppressed.

  Further, the image scanner device 10 according to the present embodiment includes a platen roller 38 disposed to face the second scanner unit 60. The brake member 14 is disposed coaxially with the platen roller 38.

  With this configuration, the platen roller 38 and the brake member 14 can be arranged in a compact space. Therefore, it is possible to reduce the size of the image scanner device 10.

  Further, in the image scanner device 10 of the present embodiment, the brake member 14 is formed of urethane rubber that is an elastic member.

  With this configuration, the impact can be more effectively mitigated by the elasticity of the brake member 14.

  Next, a modification in which a one-way clutch is connected to the brake member 14 will be described with reference to FIGS. FIG. 8 is a cross-sectional view of the main part showing a state in which the back scanner frame 12 is rotated downward in the present modification. FIG. 9 is a cross-sectional view of the main part showing a state in which the back scanner frame 12 is rotated upward. In addition, since this modified example has the same configuration except that the one-way clutch 15 is connected to the brake member 14, the same or similar members as those in the above embodiment are denoted by the same reference numerals in the drawings and the description thereof is omitted. .

  In the modification shown in FIG. 8, the brake member 14 is not integrally formed with the platen roller 38 and is a separate part. The brake member 14 is attached to the main body portion 16 of the ADF 25 via a one-way clutch 15. The brake member 14 and the one-way clutch 15 are arranged so that the platen roller 38 and the axis coincide with each other.

  The one-way clutch 15 is engaged and locked (blocked) when the roller-like brake member 14 attempts to rotate counterclockwise when viewed from the front of the image scanner device 10 shown in FIG. Further, the one-way clutch 15 releases the engagement and freely rotates when the brake member 14 tries to rotate clockwise. In addition, about the structure of the one-way clutch 15, well-known things, such as a structure provided with the nail | claw for a reverse rotation prevention with a gear, a structure provided with a cam, are applicable.

  As shown in FIG. 8, when the back scanner frame 12 rotates downward, the back scanner frame 12 tries to rotate the brake member 14 counterclockwise via the contact portion 13. However, since the one-way clutch 15 is configured to lock the counterclockwise rotation, the brake member 14 does not rotate. Therefore, a frictional force is generated between the brake member 14 and the contact portion 13 in a direction against the rotation of the back scanner frame 12. As a result, the impact when returning the back scanner frame 12 from the exposure position to the use position can be mitigated.

  On the other hand, as shown in FIG. 9, when the back scanner frame 12 rotates upward, the back scanner frame 12 tries to rotate the brake member 14 clockwise via the contact portion 13. Since the one-way clutch 15 does not lock the rotation with respect to the clockwise rotation, the brake member 14 rotates according to the rotation of the back scanner frame 12, and almost no frictional force is generated. Therefore, the back scanner frame 12 can be smoothly rotated from the use position to the exposure position.

  As described above, the image scanner device 10 according to this modification includes the one-way clutch 15 connected to the brake member 14. The one-way clutch 15 allows the brake member 14 to rotate when the back scanner frame 12 rotates from the use position to the exposed position, and prevents the brake member 14 from rotating in the opposite direction.

  With this configuration, when the back scanner frame 12 is rotated from the use position to the exposed position, the brake member 14 rotates according to the rotation of the back scanner frame 12, so that the back scanner frame 12 can be opened smoothly. Further, when the back scanner frame 12 is rotated from the exposure position to the use position, the brake member 14 has a frictional resistance acting on the back scanner frame 12 because the rotation of the brake member 14 is locked by the one-way clutch 15. Therefore, the opening / closing operation can be performed efficiently, and the impact generated by the rotation can be prevented.

  Although the preferred embodiment of the present invention has been described above, the above configuration can be further modified as follows.

  In the above embodiment, the brake member 14 is provided only at one end of the platen roller 38. Instead of this configuration, the brake member 14 is attached to both ends of the platen roller 38. You can also. Further, the brake member can be arranged at a position away from the platen roller 38.

  In the above embodiment, the brake member 14 contacts the contact portion 13 and absorbs the impact. Instead of this configuration, the brake member directly contacts the bottom surface of the back scanner frame and rotates the back scanner frame 12. It can also be configured to weaken the momentum of movement. Further, for example, the brake member can be arranged so as to be in contact with the side surface of the back scanner frame. Also with this configuration, it is possible to prevent an impact applied to the back scanner frame 12.

  The platen roller 38 and the brake member 14 which are integrally formed in the above embodiment can be configured as separate parts. The brake member 14 is not limited to the cylindrical shape as in the above-described embodiment, and can be appropriately changed according to circumstances such as a sector shape and a square shape.

  The contact portion 13 can be changed to a configuration in which a contact portion as a separate part is fixed to the back scanner frame instead of being integrally formed with the back scanner frame 12.

  In the above embodiment, the roller-like brake member 14 is brought into contact with the back scanner frame 12 (contact portion 13), and frictional resistance is generated at the contact portion. Instead of this configuration, a pinion is used as the brake member. Can be adopted. In this case, an arc-shaped rack is installed on the back scanner frame 12 side so as to mesh with the pinion, and a friction plate or a torque limiter is provided on the pinion so that resistance to rotation is generated, whereby the back scanner frame is configured. The momentum of 12 rotations can be weakened.

  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.

1 is an external perspective view showing a state of a multifunction machine including an image scanner device according to an embodiment of the present invention. 1 is a front cross-sectional view illustrating a configuration of an image scanner device according to an embodiment. FIG. 3 is a cross-sectional view of a main part showing the automatic document feeder in a state where a cover is opened. The cross-sectional perspective view which showed the state which the back scanner frame lifted. The principal part sectional drawing which shows a mode that a back surface scanner frame exists in an exposure position, and the contact part is spaced apart from the brake member. The principal part sectional view showing the state where the back scanner frame rotated from the exposure position and the contact part and the brake member contacted. FIG. 7 is a cross-sectional view of an essential part showing a state in which the back scanner frame is further rotated from the state of FIG. The principal part sectional drawing which shows a mode that a back surface scanner frame rotates from an exposure position to a use position in a modification. The principal part sectional drawing which shows a mode that a back surface scanner frame rotates from a use position to an exposure position in a modification.

Explanation of symbols

10 Image scanner device (document reading device)
DESCRIPTION OF SYMBOLS 11 Cover part 12 Back surface scanner frame 13 Contact part 14 Brake member 15 One-way clutch 20 Copy facsimile multifunction machine 23 Document tray 24 Discharge tray 25 Automatic document feeder (ADF)
30 Document transport path 31 Pickup roller 32 Separating roller 33, 34, 35 Transport roller 38 Platen roller (reading roller)
50 Scanner unit (first reading unit)
56,57 Charge-coupled device (CCD)
60 Second scanner unit (second reading unit)
61 Light source 62, 63, 64, 65 Reflection mirror 67 Condensing lens

Claims (9)

A document transport path for transporting the document;
A first reading unit for reading the first surface of the document;
A second reading unit of a reduction optical system for reading the second surface of the original;
A frame for holding the second reading unit;
An opening / closing mechanism for rotating the frame between a use position for reading a document and an exposure position at which a reading portion of the second reading unit is exposed;
A brake member arranged to contact the frame when rotating the frame to the use position;
An original reading apparatus comprising: The document reading device according to claim 1,
Having an elongated contact portion protruding from an end of the frame;
The document reading device, wherein the brake member is disposed so as to contact the contact portion. The document reading device according to claim 2,
The document reading device, wherein the contact portion is separated from the brake member when the frame is in the use position. The document reading apparatus according to claim 2 or 3,
The document reading apparatus according to claim 1, wherein the contact portion is separated from the brake member in a part of strokes including the end portion on the use position side in the rotation stroke of the frame. A document reading device according to any one of claims 2 to 4,
The document reader according to claim 1, wherein the contact portion is separated from the brake member in a part of strokes including the end portion on the exposed position side of the rotation stroke of the frame. A document reading apparatus according to any one of claims 1 to 5,
The document reading device, wherein the brake member has a roller shape. The document reading device according to any one of claims 1 to 6,
A reading roller disposed opposite to the second reading unit;
The document reading device, wherein the brake member is arranged coaxially with the reading roller. The document reading device according to any one of claims 1 to 7,
The document reading device, wherein the brake member is formed of an elastic member. The document reading device according to any one of claims 6 to 8,
A one-way clutch connected to the brake member;
The one-way clutch allows rotation of the brake member when the frame rotates from the use position to the exposed position, and prevents rotation of the brake member in the opposite direction. .

Images