JP2012129668A - Document feeder and image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate cleaning of a glass without using a dedicated cleaning member while minimizing a lifting amount of an ADF.SOLUTION: An ADF 2 is provided so as to be openable and closable with respect to an image reader. The ADF 2 comprises: reading means to read a fed document image (optical box 172); a contact glass 171 provided to be movable in a feed direction of a document and having a facing position facing the reading means to which a fed document contacts; an opening/closing guide 181 movable between a guide position to which a document is guided to contact the glass 171 and an open position forming an opening 190 retreated from the glass 171; and a movement cam 182 which reciprocates the glass 171 in the feed direction of a document. The glass 171 is provided so as to be movable by the movement cam 182 in the feed direction of a document between the facing position and a cleaning position on a side of the opening of the guide 181 moved to the open position.

Description

  The present invention relates to an original conveying apparatus that is provided so as to be openable and closable with respect to an image reading apparatus such as a scanner, a copier, or a facsimile machine and conveys an original to the image reading apparatus.

  2. Description of the Related Art Conventionally, some image forming apparatuses such as digital copying machines are provided with a document conveying device (hereinafter referred to as ADF (Auto Document Feeder)). When copying a document in the ADF with the digital copying machine provided with the ADF, the reading device provided below the ADF is moved to a predetermined reading position and stopped. Thereafter, light is emitted from the lamp unit, the original is transported along the contact glass at the reading position, the original is scanned, the reflected light is detected by the reading device, and the image (front surface) is read.

  Further, a reading device is also provided in the ADF, and after the surface of the original is read by a reading device provided below the ADF, the back surface (image) of the original is read by the reading device in the ADF. A copy image is obtained by processing in the printer unit based on the detected data (read image data).

  In the conventional ADF, in order to prevent deterioration of the read image such as color misregistration and image blurring, there is a lead roller for nipping and conveying the document whose surface is read immediately after reading, and the back surface of the back surface in the conveyance direction is downstream. A back side reader for reading is disposed. For this reason, the back side reading glass and the back side reading glass that is in contact with the document conveyed at the position opposite to the back side reading device are arranged in a deep position.

  Further, the surface of the glass also serves as a guide surface for guiding the document to be conveyed. Since the document slides, fine dust or the like may adhere to it. For this reason, it is necessary to clean the glass at the back position as described above.

  In the conventional ADF disclosed in Patent Document 1, a dedicated glass cleaning member for cleaning the back side reading glass at the above-described back position is provided to facilitate cleaning.

JP 2008-199214 A

  However, in the above-described prior art, a dedicated cleaning member is required to clean the glass. Therefore, when there is no dedicated cleaning member, the workability of cleaning the glass may be greatly deteriorated. Further, when cleaning the glass described above, it is necessary to open a conveyance guide for conveying the document on the glass, so that the ADF itself is lifted high in order to secure a space for widening the conveyance guide ( It was necessary to open it a lot).

  In view of the above problems, an object of the present invention is to provide a document conveying device that can easily clean a glass without using a dedicated cleaning member, minimizing the lifting amount of ADF. It is.

  In order to achieve the above object, the present invention is an original conveying device that is provided so as to be openable and closable with respect to an image reading apparatus that reads an image on one side of an original, Conveying means, a reading means for reading an image on the other side of the document conveyed by the conveying means, and a movably provided document along the conveying direction of the document, the conveyed document being opposed to the reading means It can be moved to a contact glass that is in contact with the contact glass, a guide position that guides the document so as to be in contact with the contact glass, and an open position that is retracted from the contact glass to form an opening. And a contact glass moving means for reciprocating the contact glass along a document conveying direction. The glass sheet is provided so as to be movable by the contact glass moving means to the cleaning position on the opening side of the guide means moved to the facing position and the opening position along the document conveying direction. And

  According to the present invention, since the contact glass is moved to the cleaning position on the opening side of the opened guide means, the contact glass can be easily reached, and the amount of opening the device can be reduced without using a dedicated cleaning member. Minimize and easily clean the contact glass.

1 is a schematic front sectional view of an image reading device. It is a schematic front sectional view showing a drive system of the image reading apparatus. It is a block diagram of an image reading device It is a principal part schematic sectional drawing explaining the image reading part vicinity. It is a principal part schematic sectional drawing explaining the glass movement of an image reading apparatus. 1 is a schematic front sectional view of an image reading device. It is a principal part schematic sectional drawing explaining the glass movement of an image reading apparatus. It is a model top view explaining the drive transmission part of an image reading apparatus. It is a figure which shows the state which opened ADF.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions. Therefore, unless specifically stated otherwise, the scope of the present invention is not intended to be limited thereto.

[First Embodiment]
The image reading apparatus according to the first embodiment will be described below. Here, a scanner provided with an openable / closable original conveying apparatus for conveying an original is illustrated as an image reading apparatus.

  As shown in FIG. 1, the image reading apparatus includes a reader unit 150 and an ADF 2. The reader unit 150 is an image reading unit (first reading unit) that reads an image on one side (front surface) of a document. An ADF (abbreviation of Auto Document Feeder) 2 is a document transport device that supplies sheet-like documents to the reader unit 150 one by one. Further, the ADF 2 includes image reading means (second reading means) inside. An original on which an image on one surface (front surface) is read by the reader unit 150 is not reversed by the image reading means (second reading means) provided inside the ADF 2 even if the original conveyed by the ADF 2 is not reversed. The (back side) image is read. Hereinafter, the reader unit 150 and the ADF 2 will be described in order.

[Reader part]
As shown in FIG. 1, the reader unit 150 includes a lamp 152 that emits light to the image surface of the document D, a mirror 153 that guides reflected light from the document D irradiated by the lamp 152 to a lens 157, and a reading sensor. CCD (charge coupled device) 158 and the like. These lamp 152, mirror 153, and CCD 158 are attached to an optical box (reading unit) 159. The optical box 159 is coupled to a motor (not shown) via a wire (not shown), and reciprocates in parallel with the document table glass 3 by the rotational drive of the motor. The motor rotates forward and backward with reference to the position of the position sensor that detects the home position of the optical box 159 to reciprocate the optical box 159. Therefore, the optical box 159 optically scans the document on the platen glass 3.

  The motor is a stepping motor. An encoder (not shown) is connected to this motor. This encoder can detect how many pulses the optical box 159 has moved. Therefore, the reader unit 150 can grasp the position of the optical box 159 by the encoder pulse from the position sensor and the encoder.

  The reflected light from the document is guided to the lens 157 by the mirror 153 and is condensed on the CCD 158 by the lens 157. The CCD 158 photoelectrically converts the reflected light reflecting the document information and outputs it as an electrical image signal to a printer unit (not shown) to form an image on a sheet of recording paper or the like as a recording target, or as data Accumulate in memory.

  The reader unit 150 reads a document in one of a fixed reading mode (original table glass document reading mode) and a flow reading mode (ADF document reading mode) selected by the user. The fixed reading mode is a mode in which a user places a document on the platen glass 3 and reads the document while moving the optical box 159 in the sub-scanning direction. The flow reading mode is a mode in which a sheet-like document is passed through the first contact glass (sheet guide) 161 above the optical box 159 stopped at the document reading position 160 by the ADF 2 to read the document.

  The ADF 2 is provided in the reader unit 150 so as to be opened and closed. In the fixed reading mode, the user lifts the front side of the ADF 2 to open the upper surface of the reader unit 150 and places the document on the exposed document glass 3. FIG. 9 is an explanatory diagram showing a state when the ADF 2 is opened with respect to the reader unit 150. The ADF 2 is connected to the reader unit 150 so as to be rotatable (openable and closable) by a hinge 77 provided on the back side.

[Document Feeder (ADF)]
The ADF 2 includes a document tray unit, a document separation unit, a document transport unit, a first reading unit, a second reading unit, a drive system, a sensor, and a control circuit. Hereinafter, each part will be described.

(Original tray)
As shown in FIG. 1, the document tray 4 can stack a plurality of documents D. On the document tray 4, a pair of width direction regulating plates 19 that regulate the ends in the width direction orthogonal to the document feeding direction are arranged so as to be slidable in the document width direction. The width direction regulating plate 19 regulates the width direction of the document D stacked on the document tray 4 so that the document can be supplied with the position in the width direction aligned when the document is supplied.

(Original separation section)
As shown in FIG. 1, a document supply roller 5 is disposed above the document tray 4. The document supply roller 5 rotates as the separation conveyance roller 8 rotates and supplies the document into the ADF. The document supply roller 5 is usually retracted to the upper position (solid line position in the figure), which is the home position, so as not to disturb the document when the document is placed on the document tray 4. When the supply of the document starts, the document supply roller 5 descends from the solid line position in the drawing to the broken line position and comes into contact with the upper surface of the document D. Since the document supply roller 5 is pivotally supported by an arm (not shown), the document supply roller 5 moves up and down as the arm swings.

  The separation pad 6 is disposed to face the separation conveyance roller 8 and is in pressure contact with the separation conveyance roller 8. For the separation pad 6, a friction member such as rubber whose friction is slightly smaller than that of the separation conveyance roller 8 is used. The separation pad 6 is configured to separate the documents D supplied by the document supply roller 5 in cooperation with the separation conveying roller 8 one by one.

(Original transport section)
The separating / conveying roller 8 often varies in conveying speed when separating documents. For this reason, the drawing roller 49 pulls out the originals separated by the separating and conveying rollers one by one and feeds them to the registration roller 12 at a stable speed. The registration roller 12 and the registration driven roller 11 are configured to straighten the direction of the original when the original sent by the drawing roller 49 is inclined.

  The first lead roller pair 32 as the first transport means includes the first lead roller 22 and the first lead driven roller 14, and transports the document toward the first contact glass 161. Further, the second lead roller pair 33 as the second conveying means is constituted by the second lead roller 23 and the second lead driven roller 16, and the document is discharged from the first contact glass 161 and also on the second contact glass 171. It is designed to be transported towards. The original conveyed by the original discharge roller pair 18 is discharged to the discharge tray 10 outside the ADF conveyance path.

  Between the first contact glass 161 and the second lead driven roller 16, a jump table 162 for scooping up the sheet from the first contact glass 161 is disposed. When the document passes through the first contact glass 161, an image on one surface (front surface) can be read by the reader unit (first reading unit) 150.

  Further, when the document passes through the second contact glass 171, an image on the other surface (back surface) can be read by the second reading means provided in the ADF 2. The second reading unit is configured by an optical box 172 having substantially the same configuration as the optical box 159 provided in the reader unit 150. Like the optical box 159, the optical box 172 includes a lamp, a mirror, a lens, a CCD, and the like.

  The second reading unit optically scans the original when the original passes through the second contact glass 171 in the same manner as when the original passes through the first contact glass 161, and converts the original image into an electrical image signal. The data is converted and output to a printer (not shown) or stored in a memory. In the reading operation (second flow reading mode) performed by the second reading unit, the surface of the document is read mainly by the reading operation (first flow reading mode) performed by the first reading unit (reader unit 150). Immediately after that, it is used to read the back side of the document. By providing this second flow reading mode, it is possible to read both sides of a document to be conveyed to a minimum.

(First reading unit)
The platen roller 24 is disposed at a position facing the first contact glass 161 for flow reading and immediately above the first reading position 160. The platen roller 24 is driven by a read motor 53 (see FIG. 2). The platen roller 24 prevents the document from being lifted or ramped at the reading position 160, thereby realizing stable reading of the document. The platen roller 24 is disposed with a predetermined gap with respect to the first contact glass 161.

(Second reading unit)
Similarly to the first reading unit, in the second reading unit, the platen roller 173 is disposed at a position opposite to the second reading position 170 of the second contact glass 171. The platen roller 173 is driven by a read motor 53 (see FIG. 2) and is disposed with a predetermined gap from the contact glass 171 and contributes to stable image reading.

(Drive system)
FIG. 2 is a diagram showing a drive system having motors and solenoids for driving the rollers and the like. The separation solenoid 57 moves the document supply roller 5 up and down. The separation solenoid 57 is configured to lift and hold the document supply roller 5 in the upper position (solid line position in the figure) which is the home position. The separation solenoid 57 holds the document supply roller 5 at a position that does not interfere with the document when the document is set on the document tray 4. Further, the separation solenoid 57 lowers the document supply roller 5 when the document supply of the ADF 2 is started, and presses the document supply roller 5 against the uppermost document on the document tray 4.

  Stepping motors are used for the separation motor 51, the read motor 53, and the document discharge motor 50. The separation motor 51 rotates the separation conveyance roller 8, the document supply roller 5, and the drawing roller 49 in the conveyance direction. The read motor 53 is configured to rotate the registration roller 12, the first lead roller 22, the first platen roller 24, the second lead roller 23, and the second platen roller 173. These rollers 12, 22, 24, 23, and 173 are driving rollers, and convey the document at a document reading speed. The document discharge motor 50 rotates the document discharge roller pair 18.

(Sensor)
As shown in FIG. 2, the document tray 4 is provided with a document set detection sensor 40 that is a transmissive optical sensor that detects that the document D is placed on the document tray 4. Further, at the lower part of the document tray 4, a document width detection for detecting the position of the width direction regulating plate 19 and detecting the width dimension (length in the direction orthogonal to the transport direction) of the document D placed on the document tray 4. A sensor 44 (see FIG. 3) is provided. Between the separation conveyance roller 8 and the registration driven roller 11, a registration sensor 7 which is a transmission type optical sensor for detecting a document is provided. The registration sensor 7 detects the leading edge of the separated and fed document and measures the timing for controlling the amount of abutment (loop amount) against the registration roller pair 11 and 12 for correcting the skew of the sheet. Used for.

  In the vicinity of the first lead roller 22, a first lead sensor (position detection sensor) 13 which is a reflection type optical sensor for detecting a document is provided. The first read sensor 13 detects the leading edge (downstream end) of the document and generates a reference signal for measuring the image reading start timing in the reader unit 150. Further, in the vicinity of the second lead roller 23, a second lead sensor 20 which is a reflection type optical sensor for detecting a document is provided. Similar to the first lead sensor, the second read sensor 20 issues a reference signal for measuring the image reading start timing of the second reading means. On the upstream side of the document discharge roller pair 18, a document discharge sensor 17, which is a transmissive optical sensor for detecting a document, is provided. The document discharge sensor 17 is used to measure the document discharge timing.

(Control circuit)
FIG. 3 is a block diagram of an ADF control circuit. The control circuit is configured around a microprocessor (hereinafter referred to as “CPU”, control means) 54. Various load drive circuits and sensors are connected to the input / output port of the CPU 54. Although not shown, the control circuit includes a RAM backed up by a battery and a ROM storing control sequence software.

  The separation motor 51, the read motor 53, and the document discharge motor 50 are driven by respective stepping motor drivers. Each driver is supplied with a phase excitation signal and a motor current control signal from the CPU 54. The separation solenoid 57 is driven by a driver, is connected to an input / output port of the CPU 54, and controls operation based on a signal of the CPU 54.

  Various sensors such as the registration sensor 7, the document set detection sensor 40, the first lead sensor 13, the second lead sensor 20, the document discharge sensor 17, and the document width detection sensor 44 are connected to an input port of the CPU 54. These sensors monitor the behavior of the document and the behavior of the movable part in the apparatus.

(Description of ADF operation)
The document set detection sensor 40 detects whether or not the document D is placed on the document tray 4. If a document is placed, the document width detection sensor 44 on the document tray 4 detects the document size. Further, the separation solenoid 57 lowers the document supply roller 5. The document supply roller 5 contacts the uppermost document and feeds the document between the separation conveyance roller 8 and the separation pad 6.

  When a plurality of documents D supplied from the document tray 4 overlap, the separation conveyance roller 8 and the separation pad 6 separate the documents one by one and convey them to the registration roller pairs 11 and 12. The registration roller pair 11, 12 corrects the document straight when the document is skewed, and conveys the document to the nip between the first lead roller 22 and the first lead driven roller 14 by the first registration roller 12.

  The first lead roller 22 and the first lead follower roller 14 hold the original with a predetermined original holding force and rotate to pass through the gap between the first contact glass 161 and the platen roller 24, so that the second lead roller 23 and the second lead driven roller 16 are fed into the nip. The reader unit (first reading unit) 150 is an optical box 159 stopped at the first reading position 160, and scans a document passing through the gap between the first contact glass 161 and the platen roller 24, thereby causing one image surface to be scanned. Read. Further, immediately after that, the other image surface is read by scanning the document passing through the gap between the second contact glass 171 and the platen roller 173 with the optical box 172 constituting the second reading means fixed in the document conveying device. .

(Operation of contact glass)
The operation of the contact glass 171 in the second reading unit will be described with reference to FIG. In order to perform stable image reading with the ADF in the second flow reading mode, it is necessary to perform so-called shading that corrects sensitivity deterioration of the document illumination lamp and the CCD sensor every predetermined period. In the second reading unit, a white reference plate (white reference unit) 175 for shading is pasted on the side of the document conveying surface of the contact glass 171 in order to perform correction including factors such as glass transmittance. The white reference plate 175 is provided on the upstream side in the document conveyance direction with respect to the position of the contact glass 171 facing the optical box 172 constituting the second reading unit. For this reason, when performing shading, the contact glass 171 is moved downstream in the document conveying direction (in the direction of arrow B) as shown in FIG. 4A, and the white reference plate 175 is moved as shown in FIG. It is positioned at a position facing the second reading means (reading position 170).

  In order to scoop up the document that has contacted the contact glass again into the transport guide during document transport, when the document tip reaches the glass edge, a jump trapezoid is formed from the surface below the document contact surface. Need to lift. If the white reference plate 175 of the contact glass 171 is pasted on the downstream side in the conveyance direction with respect to the reading position 170, the conveyed document is a step between the white reference plate 175 and the glass 171 as shown in FIG. Will cause a conveyance failure. For this reason, as shown in FIG. 4A, the white reference plate 175 is attached to the upstream side of the contact glass 171 in the transport direction so as not to affect the document transport.

  Therefore, as described above, when shading is performed, the contact glass 171 is moved downstream in the document transport direction (in the direction of arrow B) from the position when reading the document image shown in FIG. It has moved to the shading position shown in FIG. That is, the contact glass 171 performs shading at a position where the conveyed document is deeper than the reading position.

  As shown in FIG. 5, the contact glass 171 is held by a glass holder 183 that is urged by a spring 185 in the direction of arrow C (upstream in the document conveying direction). A glass shading moving cam 186 provided on the reading opening / closing guide 181 is in contact with the glass holder 183.

  Here, the reading opening / closing guide 181 will be described. The reading opening / closing guide 181 is guide means for guiding the document so as to face the contact glass 171 so as to face the contact glass 171. The reading opening / closing guide 181 is provided so as to be rotatable around a rotation center on one side in the document conveying direction via a facing position facing the optical box 172 constituting the second reading means. Here, the reading opening / closing guide 181 is exemplified as having a rotation center in the vicinity of the discharge roller, which is on the downstream side in the document conveying direction with respect to the facing position.

  The reading open / close guide 181 moves around the center of rotation near the discharge roller to a guide position for guiding the document so as to contact the contact glass 171 and an open position for retracting from the contact glass 171 to form an opening. It is possible. Specifically, as shown in FIG. 5, the reading opening / closing guide 181 has a closed position (see FIG. 5A) where the moving cam 186 contacts the glass holder 183, and the contact between the moving cam 186 and the glass holder 183. It can be moved to an open position (see FIG. 5B) where the contact is released. The moving cam 186 is configured so that the driving force from the lead motor 53 is transmitted via the one-way clutch.

  Since the original is not conveyed when the contact glass 171 is moved, the contact glass 171 is usually moved by using a read motor 53 that rotates a lead roller. Here, at the time of reading and conveying a document, a one-way clutch provided in a drive transmission path from the motor 53 acts to prevent transmission of driving to move the contact glass 171. When the contact glass 171 is moved, the lead motor 53 is rotated (reversed) in the direction opposite to the conveying direction, and the contact glass 171 is moved to a position for shading while the roller is also reversed. That is, as shown in FIG. 5, the glass shading moving cam 186 provided on the reading opening / closing guide 181 is configured to rotate only when the read motor 53 rotates in the direction opposite to the document conveying direction. Following the rotation of the moving cam 186, the contact glass 171 moves from the reading position shown in FIG. 4A to the shading position shown in FIG. 4B, and also moves from the shading position to the reading position. That is, following the rotation of the moving cam 186, the contact glass 171 reciprocates between the reading position and the shading position along the document conveyance direction.

  Since the document is conveyed while being in contact with the contact glass 171, dust and paper dust on the document may drop and adhere, or dirt on the document may be transferred. If dust adheres to the contact glass 171 or gets dirty, it will appear as a black streak when the document is read and must be cleaned. The contact glass 161 of the first reading unit may also become dusty or dirty. However, since the contact glass 161 is easily dewed if the ADF 2 is lifted around the hinge portion (hinge 77) (see FIG. 9), cleaning is easy.

  On the other hand, when cleaning the contact glass 171 of the second reading unit, first, the ADF 2 is opened with respect to the reader unit 150 so as to lift up (see FIG. 9). Thereafter, as shown in FIG. 6, the reading opening / closing guide 181 having the rotation center near the discharge roller is moved from the document guide position to the opening position where the opening 190 is formed by retracting from the contact glass 171. Open and clean. The reading open / close guide 181 is integrally provided with a second lead roller 23, a second lead driven roller 16, and a second platen roller 173. Therefore, the second contact glass 171 is exposed by opening the reading opening / closing guide 181 as shown in FIG.

  FIG. 6 shows the operation of the contact glass 171 during glass cleaning. As shown in FIG. 6, the reading opening / closing guide 181 has a protrusion (holding portion) 184 for holding the contact glass 171 at a facing position (solid line position in the figure) facing the second reading means. A protrusion 184 protruding from the reading opening / closing guide 181 is in contact with the glass holder 183 holding the contact glass 171 located at the position shown in FIG. 7A, and the movement of the glass holder 183 in the direction of arrow C is restricted. It is a stopper to do. The projection 184 holds the glass holder 183 at the position shown in FIG. 7A, and the contact glass 171 held by the glass holder 183 is held at the solid line position (guide position for guiding the document) shown in FIG. The Further, as shown in FIG. 5B, the shading movement cam 186 is configured integrally with the reading opening / closing guide 181.

  As shown in FIG. 6, by opening the reading opening / closing guide 181, the protrusion 184 as a stopper is released from the glass holder 183 and released by the protrusion 184, and the shading movement cam 186 is integrated with the reading opening / closing guide 181. Evacuate to. Therefore, the glass holder 183 moves in the direction of arrow C shown in FIG. 7A by the urging force of the spring 185, and abuts against the glass cleaning moving cam 182 as shown in FIG. 7B. The glass cleaning movement cam 182 is contact glass moving means for reciprocating the contact glass 171 along the document conveyance direction. By rotating the glass cleaning moving cam 182, the contact glass 171 moves from the position shown in FIG. 7B to the position shown in FIG. 7C. That is, the contact glass 171 moves from the reading position (solid line position shown in FIG. 6) to the cleaning position (broken line position shown in FIG. 6) near the contact glass 161 on the opening 190 side.

  The second lead roller pair 33 positioned between the contact glass 171 and the contact glass 161 is retracted together with the reading opening / closing guide 181 by rotating the reading opening / closing guide 181 to the open position. Therefore, by rotating the glass cleaning moving cam 182, the contact glass 171 can be moved to the vicinity of the contact glass 161 on the upstream side in the document transport direction, which is the opening side (the dotted line position in FIG. 6).

  The vicinity of the contact glass 161 serving as the first reading unit is an area where the reading opening / closing guide 181 is opened to the maximum, so that even if the opening angle of the reading opening / closing guide 181 is small, sufficient to put a hand to clean the contact glass 171 Space is reserved. Even if the opening angle of the reading opening / closing guide 181 is small, the contact glass 171 can be cleaned, that is, the amount of lifting of the ADF 2 is small, and the operability during glass cleaning is improved.

  When the glass cleaning moving cam 182 is further rotated, the glass holder 183 is returned to the reading position (solid line position shown in FIG. 6) which is a predetermined position, and when the reading opening / closing guide 181 is closed, the contact glass 171 is again moved to the predetermined reading position. Return to.

  Here, the glass cleaning movement cam 182 is configured to rotate when the lead motor 53 rotates. However, as described above, the glass cleaning movement cam 182 contacts the glass holder 183 only when the reading opening / closing guide 181 is open, and the glass cleaning movement cam 182 does not contact the glass holder 183 when the reading opening / closing guide 181 is closed. It has been released (separated). Therefore, the rotation of the glass cleaning movement cam 182 is involved in the movement of the contact glass 171 only when the reading opening / closing guide 181 is open. That is, during a normal image reading operation, the contact glass 171 is not moved by the glass cleaning moving cam 182 even if the lead motor 53 is rotating.

  Then, the glass cleaning movement cam 182 is rotated by using a jam processing dial 92 (see FIG. 8) as an operation unit for rotating each roller in order to handle a paper jam. .

  FIG. 8 is a schematic diagram for explaining a drive transmission unit that transmits the drive from the read motor 53 to each roller.

  The motor gear 53 a of the read motor 53 meshes with a lead roller gear 22 a provided on the lead roller 22 shaft and a platen roller gear 24 a provided on the platen roller 24 shaft. A gear 90 is provided on the side of the platen roller 24 opposite to the platen roller gear 24a. The gear 90 meshes with a dial gear 91 that rotates integrally with the jam handling dial 92.

  The platen roller gear 24 a meshes with the first idle gear 93, and the first idle gear 93 meshes with the second lead roller gear 23 a provided on the shaft of the second lead roller 23. The second lead roller gear 23 a meshes with the second idle gear 94, and the second idle gear 94 meshes with a cam gear 95 provided on the shaft of the glass cleaning moving cam 182.

  Although not shown in FIG. 8, the drive transmission unit (drive transmission path) is configured so that the drive from the lead motor 53 is also transmitted to the roller shafts of the registration roller 12 and the platen roller 173. .

  The cam gear 95 meshes with a cam gear 96 for transmitting driving to a shading moving cam 186 for moving the contact glass 171 to the shading position. As described above, when the document is normally conveyed, the one-way clutch built in the cam gear 96 acts, and the drive is not transmitted to the shading moving cam 186. On the other hand, the driving force is transmitted to the shading movement cam 186 by rotating the lead motor 53 in the direction opposite to that during document conveyance. Due to the transmission of the driving force from the read motor 53, the contact glass 171 is moved to the upstream side in the document conveying direction and positioned at the shading position. By using the drive system in this way, a simpler configuration can be achieved.

  Here, the jam processing dial 92 as an operation unit is an operation dial operated by the user for jam processing. The jam processing dial 92 is connected to a glass cleaning moving cam 182 as shown in FIG.

  When the user rotates the jam handling dial 92, each roller driven by the read motor 53 rotates. That is, at the time of jam processing, by operating the jam processing dial 92 and rotating each roller, the document staying on the transport path can be moved to a position where it can be easily removed from the transport path.

  Here, since the glass cleaning movement cam 182 is incorporated in the drive system driven by the lead motor 53, the glass cleaning movement cam 182 rotates with each roller when the user rotates the jam processing dial 92. It has become.

  However, the glass cleaning movement cam 182 engages with the glass holder 183 that supports the contact glass 171 only when the reading opening / closing guide 181 is open. Therefore, the glass cleaning movement cam 182 does not act on the glass holder 183 in a normal jam processing operation performed with the reading opening / closing guide 181 closed.

  That is, when cleaning the contact glass 171, after opening the reading opening / closing guide 181, the jam processing dial 92 is manually rotated, the glass cleaning movement cam 182 is rotated, and the contact glass 171 is moved upstream in the document conveying direction. . In other words, here, an operation unit for manually rotating the roller during the jam processing and an operation unit for manually moving the contact glass 171 are combined.

  In addition, although the operation dial was illustrated as mentioned above as an operation part which a user operates, it is not limited to this, For example, a lever-shaped operation part may be sufficient.

  As described above, according to the present embodiment, the contact glass 171 is moved to the cleaning position on the opening side of the opened reading opening / closing guide 181, so that the contact glass 171 can be easily reached. That is, even without using a dedicated cleaning member, the amount of opening the ADF can be minimized and the contact glass 171 can be easily cleaned.

  Further, even when the contact glass 171 is moved deeper by performing shading or the like, the glass can be easily cleaned if the contact glass 171 can be moved in the vicinity of the opening during cleaning.

  Further, the contact glass 171 is cleaned only when the reading opening / closing guide 181 is opened. Therefore, if the contact glass 171 moves only when the reading opening / closing guide 181 is opened, a dedicated drive mechanism for moving the contact glass 171 may not be provided.

  Further, since the contact glass is cleaned when the operation of the apparatus is stopped, the contact glass 171 can be cleaned regardless of the energized state of the apparatus if the contact glass 171 can be manually moved. .

  Furthermore, since the contact glass 171 is moved by a driving source such as a motor during the shading operation, shading can be performed when the apparatus performs an operation other than reading, and the reading sensor can be kept in a good state at all times.

[Other Embodiments]
In the above-described form, the form in which the glass cleaning movement cam 182 is incorporated in the drive transmission system driven by the lead motor 53 is illustrated in order to move the contact glass 171 with the jam processing dial 92. However, the present invention is not limited to such a form. For example, the glass cleaning moving cam may be separated from the drive transmission system using the lead motor 53. That is, you may make it provide the operation part separate from the jam processing dial for rotating the glass cleaning movement cam in order to move the contact glass 171 manually. In this case, there is no need for a mechanism for separating the glass cleaning movement cam 182 and the glass holder 183 from each other in the normal state in which the reading opening / closing guide 181 is closed as described in the above embodiment.

  Moreover, although the form which moves the contact glass 171 by rotating the glass cleaning movement cam 182 by the user operating an operation part manually was illustrated, it is not limited to this. The contact glass 171 may be moved by automatically rotating the glass cleaning moving cam 182 by a motor. In this case, for example, when the user inputs from the operation panel (not shown) to execute the cleaning mode, the CPU 54 rotates the glass cleaning movement cam 182 to move the contact glass 171 to the cleaning position. Control. Further, a sensor for detecting that the ADF 2 is closed with respect to the reader unit 150 is provided. When it is recognized that the ADF 2 is closed by a signal from this sensor, or when the end of the cleaning mode is set on the operation panel, the CPU 54 controls the motor so as to return the contact glass 171 to the position for performing the reading operation. To do.

  In the above-described embodiment, after one image surface of the document is read by the reader unit (first reading unit) outside the ADF, the other image of the document is read by the image reading unit (second reading unit) in the ADF. Although the configuration for reading the surface has been described, the present invention is not limited to this. For example, the document transport path may be reversed, that is, the document may be read by the reader unit outside the ADF after the document is read by the image reading unit in the ADF. In this case, the glass is moved toward the downstream side of the document conveyance during shading, and further, at the time of glass cleaning, the roller pair or guide between the reading position by the reading means in the ADF and the reading position of the reader unit is retracted. Thus, the contact glass may be moved to a position further downstream in the transport direction than the shading position. However, the workability at the time of glass cleaning can be improved by simply moving the glass to the vicinity of the opening of the guide, in this case, the shading position, without retracting the roller pair.

  Further, in the above-described embodiment, the configuration in which the rotation center of the reading opening / closing guide is provided on the downstream side in the document conveying direction via the facing position facing the reading unit is exemplified. Alternatively, a configuration provided on the upstream side in the document conveyance direction may be employed. In any configuration, if the contact glass can be moved to the cleaning position on the opening side of the reading opening / closing guide on the other side in the document conveying direction through the facing position, the workability at the time of glass cleaning is improved. Is improved.

  In the above-described embodiment, the scanner is exemplified as the image reading apparatus provided with the document conveying device that can be opened and closed. However, the present invention is not limited to this. For example, another image such as a copier, another image reading device (image forming device) having a image forming unit for forming an image on a sheet to be recorded, or a multifunction device combining these functions. It may be a reading device (image forming device). The same effect can be obtained by applying the present invention to a document conveying device provided in such an image reading apparatus (image forming apparatus) that can be opened and closed.

D ... Original 2 ... ADF
14 ... 1st lead driven roller 16 ... 2nd lead driven roller 22 ... 1st lead roller 23 ... 2nd lead roller 24 ... Platen roller 32 ... 1st read roller pair 33 ... 2nd read roller pair 53 ... Lead motor 54 ... CPU
77 ... Hinge 92 ... Jam processing dial 150 ... Reader section 159 ... Optical box 160 ... First reading position 161 ... First contact glass 170 ... Second reading position 171 ... Second contact glass 172 ... Optical box 173 ... Platen roller 175 ... White reference plate 181 ... Opening / closing guide 182 ... Glass cleaning moving cam 183 ... Glass holder 184 ... Projection 185 ... Spring 186 ... Glass shading moving cam 190 ... Opening

Claims (6)

A document conveying device that is provided so as to be openable and closable with respect to an image reading device that reads an image on one side of a document, and conveys the document to the image reading device,
Conveying means for conveying an original;
Reading means for reading an image on the other side of the document conveyed by the conveying means;
A contact glass provided so as to be movable along a document conveying direction, and a document to be conveyed is in contact with the reading unit at a facing position;
A guide means provided so as to be movable between a guide position for guiding the document so as to contact the contact glass and facing the contact glass; and an open position for retracting from the contact glass to form an opening;
Contact glass moving means for reciprocating the contact glass along the document conveying direction;
Have
The contact glass is provided so as to be movable by the contact glass moving means to the cleaning position on the opening side of the guide means moved to the opening position and the facing position along the document transport direction. An original conveying apparatus characterized by the above. The guide means has a holding portion for holding the contact glass at the facing position,
The contact glass is held at the facing position in a state of being disengaged from the contact glass moving means by the holding portion of the guide means located at the guide position, and the guide means is moved to the open position by moving the guide means to the open position. The holding by a holding part is cancelled | released, it engages with the said contact glass moving means, and the reciprocation to the said opposing position and the said cleaning position by the said contact glass moving means is attained. Document transport device. The guide means is provided so as to be rotatable around a rotation center on one side in the document conveying direction through a facing position facing the reading means.
3. The document conveying device according to claim 1, wherein the contact glass is movable to a cleaning position on the opening side of the guide means, which is on the other side in the document conveying direction via the facing position.   4. An operation unit coupled to the contact glass moving means, wherein the contact glass is reciprocated between the facing position and the cleaning position by operating the operation unit. The document feeder according to any one of the above. The contact glass has a white reference portion for correcting the reading unit on the upstream side in the document conveying direction with respect to a position facing the reading unit,
5. The apparatus according to claim 1, wherein the white reference unit is movably provided downstream in the document conveyance direction in order to move the white reference unit to a position facing the reading unit. 6. Document transport device. An image reading device provided with an openable and closable document conveying device for conveying a document and reading an image on one side of the document,
An image reading apparatus comprising the document conveying device according to claim 1 as the document conveying device.

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