JP5141700B2 - Image reading apparatus, image forming apparatus, and automatic document feeder - Google Patents

Description

  The present invention relates to an image reading apparatus, an image forming apparatus, and an automatic document feeder, and more particularly to a sheet-through type automatic document feeder and an image forming apparatus and an image reading apparatus equipped with the automatic document feeder.

  2. Description of the Related Art In recent years, there has been a rapid increase in demand for an image reading apparatus called a dual scan reading, which further includes a reading unit and reads the front side of a document by the sheet-through method and simultaneously reads the back side. Since dual scan reading allows double-sided scanning with the shortest path, compared to single scan reading, in addition to high productivity and low noise, conveyance failures such as paper jams can be reduced, and there is an advantage in high reliability.

  In the sheet-through type image reading apparatus, the image reading position is fixed on a transparent member (reading glass), and the image surface of the conveyed document is optically read through the reading glass. For this reason, when dust or dirt adheres to the reading glass, the portion of the document surface that is blocked by the foreign matter becomes streak noise.

  As a technique for removing dust and dirt adhering to the reading glass, Japanese Patent Laid-Open No. 2000-270152 (hereinafter referred to as Patent Document 1) arranges a cleaning member on a rotating member provided at a position facing the reading glass, and rotates the rotating member. A technique for removing dust and dirt adhering to the reading glass by rotating the lens is disclosed. Japanese Patent Laid-Open No. 2002-64687 (hereinafter referred to as Patent Document 2) and Japanese Patent Laid-Open No. 2008-252387 (hereinafter referred to as Patent Document 3) also disclose a similar configuration. As disclosed in Patent Document 3, the rotating members disclosed in these documents are rotated between a document to be conveyed and the document.

JP 2000-270152 A JP 2002-64687 A JP 2008-252387 A

  However, it has been found that in such a reading apparatus, the read image is likely to be disturbed on one side.

  SUMMARY An advantage of some aspects of the invention is that it provides an image reading apparatus, an image forming apparatus, and an automatic document feeder that can ensure image quality particularly in dual scan reading. Yes.

In order to achieve the above object, according to an aspect of the present invention, an image reading apparatus includes a first reading unit and an automatic document conveying device provided opposite to the first reading unit. In order to clean the first transparent member provided at a position corresponding to the reading position of the first reading means on the conveying path of the conveying means and the conveying means for conveying the original one by one by the cleaning operation. The first cleaning unit provided at a position opposite to the first transparent member, and the first cleaning unit provided on the surface opposite to the first reading unit with respect to the document conveyed on the conveyance path, is conveyed. The second reading means for optically reading the surface opposite to the surface read by the first reading means of the original document via the second transparent member on the transport path, and the second transparent member are cleaned. It is provided at a position opposite to the second transparent member for cleaning by operation. And second cleaning means is, with and an absorbing means for absorbing the fluctuation component due arranged cleaning operation in the second reading hand stage, absorbing means toward the second reading means to the second cleaning means As the force F to be pressed, the following relationship: F> Fs + Fr−Fc (where Fr: force in the direction of lifting the second reading means by contact of the second cleaning means in the cleaning operation, Fc: second reading) The weight F of the means, Fs: a force F satisfying the force of the second reading means due to the paper scraping when the original comes into contact .

  Preferably, each of the first cleaning unit and the second cleaning unit has a configuration in which a cleaning member is added to the rotating body, and the cleaning operation is an operation of rotating the rotating body, and the cleaning member is moved by the cleaning operation. Contact the first transparent member or the second transparent member.

More preferably, a part of the rotating body constitutes a part of the transport path.
More preferably, in the first cleaning unit and the second cleaning unit, the center of rotation and the position of the center of gravity are different.

Preferably, the absorbing means is a spring.
Alternatively, preferably, the absorbing means is a damper.

  Preferably, the first reading unit includes a CCD (Charged Coupled Device), and the second reading unit includes a CIS (Contact Image Sensor).

According to another aspect of the present invention, an image forming apparatus includes the above-described image reading apparatus.
According to still another aspect of the present invention, the automatic document feeder is provided at a position corresponding to the reading position of the reading device on the conveying path of the conveying means and the conveying means for conveying the documents one by one. A first cleaning member provided at a position opposite to the first transparent member for cleaning the first transparent member by a cleaning operation; and a document on the reading device side with respect to the document conveyed on the conveyance path. A reading means provided on the surface opposite to the surface for optically reading a surface opposite to the surface read by the reading device of the conveyed document through a second transparent member on the transport path; for cleaning by the cleaning operation the second transparent member, absorbent for absorbing the second cleaning means provided in a position opposite to the second transparent member, a fluctuation component due to the cleaning operation is arranged to read the handle stage and means, absorption means the reading means second cleaning hands As the force F to be pressed toward the surface, the following relationship: F> Fs + Fr−Fc (where Fr: force in the direction of lifting the reading means by contact of the second cleaning means in the cleaning operation, Fc: dead weight of the reading means, fs: Ru der those resulting force F that satisfies the force) acting on the reading means by stiffness of the paper when the document is in contact.

  Preferably, each of the first cleaning unit and the second cleaning unit has a configuration in which a cleaning member is added to the rotating body, and the cleaning operation is an operation of rotating the rotating body, and the cleaning member is moved by the cleaning operation. Contact the first transparent member or the second transparent member.

More preferably, a part of the rotating body constitutes a part of the transport path.
More preferably, in the first cleaning unit and the second cleaning unit, the center of rotation and the position of the center of gravity are different.

Preferably, the absorbing means is a spring.
Alternatively, preferably, the absorbing means is a damper.

  Preferably, the reading means includes a CIS (Contact Image Sensor).

  According to the present invention, it is possible to suppress deterioration in quality of a read image.

1 is a diagram illustrating a specific example of an image reading apparatus according to an embodiment. It is a figure which shows the specific example of a structure of the 2nd reading part which is a reading mechanism which employ | adopted the CIS (Contact Image Sensor) system included in an image reading apparatus. It is a figure which shows the specific example of a structure of the rotary body contained in the 2nd reading part of an image reading apparatus. It is a figure for demonstrating the positional relationship of a rotary body and reading glass accompanying rotation of a rotary body. It is a figure which shows the specific example of the relationship between the rotation angle of a rotary body, and circumferential speed. FIG. 3 is a diagram illustrating a first specific example of a configuration for suppressing vibration of members in the automatic document feeder. 6 is a time chart for explaining control as a second specific example of a configuration for suppressing vibration of members in the automatic document feeder.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same.

  Referring to FIG. 1, an image reading apparatus 100 according to an embodiment includes an ADF (Auto Document Feeder) unit 101 for automatically conveying a document, a first reading unit 102A for reading a document, The ADF unit 101 includes a second reading unit 102B for reading a document, and a control unit 500 for performing overall control and image processing.

  An image reading apparatus 100 shown in FIG. 1 is a copier, a printer, a scanner, a facsimile transmitter / receiver, or an MFP (Multi Function Peripheral) having a function of any two or more of these apparatuses. ) And the like.

  In the ADF unit 101, the documents stacked on the document tray 200 are sent out one by one to the conveyance path by a pair of pickup rollers arranged with the conveyance path interposed therebetween. The sent document is transported from the transport path (1) to (2) to the reading position 211 of the first reading unit 102A. The document that has passed through the reading position 211 is transported by the transport roller 212 and is transported to the second reading unit 102B through the document transport path (3). Thereafter, the document read by the second reading unit 102B is discharged to the discharge tray 214 through the conveyance path (4). A paper passing sensor 217 is provided in the vicinity of the conveyance roller 212 to detect conveyance of the original on the original conveyance path (3).

  The first reading unit 102A is a reading mechanism that adopts a CCD (Charged Coupled Device) method. In other words, the light source 206 irradiates the first surface represented below in FIG. 1 of the document that passes through the conveyance path in the ADF unit 101 corresponding to the reading position 211. The light reflected from the first surface of the document by the irradiation light is a reading glass 215 which is an example of a plate-like transparent member provided in the ADF unit 101, a mirror group 207 and a lens in the first reading unit 102A. The light is received by the CCD sensor 209 through 208. The CCD sensor 209 converts the received light signal into RGB data by photoelectric conversion and outputs the RGB data to the control unit 500.

  The second reading unit 102B is a reading mechanism that is provided in the ADF unit 101 and adopts a CIS (Contact Image Sensor) method. That is, referring to FIG. 2, light source 301 irradiates a second surface which is the back surface of the first surface of the document passing through reading position 306, that is, the surface represented upward in FIG. 1. The light reflected from the second surface of the document by the irradiation light is received by a CMOS (Complementary Metal Oxide Semiconductor) sensor 303 through a reading glass 302 which is an example of a plate-like transparent member. The CMOS sensor 303 converts R, G, and B received light signals into RGB data and outputs the RGB data to the control unit 500.

  The original is conveyed to the second reading unit 102B through the first reading unit 102A, and the first side and the second side are read in each of them, so that both sides can be read without turning the document upside down in the conveyance process. It becomes possible. That is, the first reading unit 102A and the second reading unit 102B are included in the double-sided reading mechanism of the document.

  The control unit 500 includes a CPU (Central Processing Unit) (not shown), reads out and executes a program stored in the memory 600, and executes an image processing unit 501 that is a function for performing image processing, and driving of each unit The drive control unit 502 that is a function for controlling the above is realized. These functions may be realized by processing of the CPU, or may be realized by hardware such as an electric circuit.

  The image processing unit 501 generates image data based on the RGB data from the first reading unit 102A and the RGB data from the second reading unit 102B. The generated image data is printed on output paper or the like.

  The drive control unit 502 is connected to a sensor such as a paper passing sensor 217 installed in the ADF unit 101, a sensor 312 (see FIG. 2) included in the second reading unit 102B, an operation panel (not shown), and the like. The input of these sensor signals and operation signals is accepted. Further, the drive control unit 502 includes a drive mechanism such as a transport roller 212 (a pulse motor, a motor drive IC (Integrated Circuit) for controlling the pulse motor, etc.), a drive mechanism of the first reading unit 102A, and a second reading. The drive mechanism of the unit 102B is communicably connected, and the drive is controlled based on the input sensor signal or operation signal.

  The image reading apparatus 100 may be connected to the image forming unit 700 as shown in FIG. 1, and the image reading apparatus 100 functions as a part of an image forming apparatus such as an MFP by being connected in this way. . In this case, the control unit 500 is electrically connected to the image forming unit 700 and outputs the generated image data. When the image forming unit 700 is a printing apparatus, the generated image data is printed on output paper or the like.

  Referring to FIG. 2 again, the second reading unit 102B is further provided with a document so that the image surface of the document does not come into contact with the glass surface. A guide 304 provided at a position sandwiching the conveyance path for guiding, and a rotating body 310B provided at a position facing the CMOS sensor 303 with the reading glass 302 interposed therebetween at the reading position 306 are included. In the following description, the side of supplying (sending out) the original to the reading position 306 while passing the paper passing sensor 217 by the rotation of the conveying roller 212 with the reading position 306 as a reference is referred to as “upstream side in the conveying direction”. The side where the read document is sent from the reading position 306 by the rotation of the transport roller 212 is referred to as “the downstream side in the transport direction”.

  The document conveyed on the glass surface of the reading glass 302 is guided by being sandwiched between guides 304, so that the image surface is not in contact with the surface of the reading glass 302, and from the upstream side to the downstream side. It is conveyed.

  The reading position 306 of the guide 304 is open on both the side close to and far from the reading glass 302. Therefore, the document conveyed from the upstream side along the guide 304 faces the reading glass 302 without interposing anything at the reading position 306. When the document is not at the reading position 306, the rotating body 310 </ b> B is opposed to the reading glass 302 without interposing anything at the reading position 306.

  As shown in FIG. 2, the rotating body 310 </ b> B has a cylindrical shape whose cross section is a shape in which a part of a circular surface is flat, and a brush-like cleaning member 31 that can be elastically deformed on the flat surface. Provided. For example, the cleaning member 31 is made by implanting conductive polyimide resin. A white reference surface 32 for shading correction is provided on the surface of the rotating body 310B other than the cleaning member 31 provided.

  Referring to FIG. 3, the rotating body 310 </ b> B is arranged so that the rotation axis thereof is parallel to the longitudinal direction of the reading glass 302 (that is, the CMOS sensor 303), and the cleaning member 31 and the white reference surface 32 are read from the reading glass 302. Opposite the position 306, it is rotatably arranged. Assuming that the cleaning member 31 and the white reference surface 32 are axes extending along the document conveyance direction, the cleaning member 31 and the white reference surface 32 extend in a line shape orthogonal to the axis.

  A sprocket 331 fixed to one end of the rotating body 310B is connected to an output sprocket 332 of a motor 234B, which is a driving mechanism of the rotating body 310B, via a timing belt 333. The motor 234B is a stepping motor that can rotate forward and backward.

  The rotating body 310B rotates forward or reverse in accordance with a predetermined timing and speed in conjunction with the rotation of the motor 234B. A motor 234 </ b> B that is a driving mechanism of the rotating body 310 </ b> B rotates according to a control signal from the control unit 500. Further, a pulse signal representing the rotation of motor 234B is output to control unit 500. By counting this pulse signal, the controller 500 can obtain the rotation speed of the motor 234B, that is, the rotation amount of the rotating body 310B.

  As shown in FIG. 1, the first reading unit 102A includes a rotating body 310A similar to the rotating body 310B included in the second reading unit 102B. The rotating member 310A provided in the first reading unit 102A is also provided with the same cleaning member and white reference surface. The rotating body 310A is also connected to the motor 234A via a timing belt in the same manner as the rotating body 310B, as shown in part in FIG. 3, and rotates as the motor 234A rotates.

  As the rotating body 310B rotates, a first position where the white reference surface 32 shown in FIG. 4 is in a position facing the reading glass 302 and the cleaning member 31 is not facing the reading glass 302, and FIG. The illustrated cleaning member 31 is in a position facing the reading glass 302 and the white reference surface 32 is in a position not facing the reading glass 302. The first position is a non-cleaning position and is a home position, and the second position is a cleaning position. The positional relationship between the rotating body 310A and the reading glass 215 is the same.

  Rotating bodies 310A and 310B stand by at the first position which is the home position. When the motors 234A and 234B are driven to rotate in accordance with a control signal from the drive control unit 502, the rotating bodies 310A and 310B rotate clockwise from the first position, which is the home position, and pass through the second position to the first. Return to position. In synchronization with this rotation, the tip of the elastically deformable brush-like cleaning member 31 rubs the surface of the reading glass 302 or the reading glass 215. As a result, foreign matter on the reading glass 302 or the reading glass 215 is captured by the cleaning member 31 and removed from the reading position 306 or the reading position 211. The operation of rotating the rotators 310A and 310B one or more times is also referred to as “cleaning operation”.

  When a plurality of documents are continuously conveyed, a cleaning operation is performed during a period in which no reading operation is performed between the documents. Specifically, regarding the first reading unit 102 </ b> A, during the period from when the trailing edge of the preceding first document passes the reading position 211 to when the leading edge of the subsequent second document reaches the reading position 211, The rotating body 310A rotates a plurality of times to perform the cleaning operation. Similarly, in the subsequent second reading unit 102B, in the period from when the trailing edge of the first document passes the reading position 306 to when the leading edge of the second document reaches the reading position 306, the rotating body 310B. Rotates a plurality of times to perform the cleaning operation.

  By the way, as described above, the cleaning member comes into contact with the reading glass in accordance with the rotating operation of the rotating body in the cleaning operation in any of the reading units, so that vibration occurs in the reading unit and the rotating body due to the contact during the cleaning operation. I understood. Further, as shown in FIGS. 2 and 3, the rotary members 310A and 310B have a cylindrical shape with a cross-sectional shape in which a part of the circular surface is flat, and the cleaning member is provided on the flat surface. 31 is provided. Therefore, the rotation centers of the rotators 310A and 310B do not coincide with the position of the center of gravity. Accordingly, as shown in FIG. 5, when the rotating bodies 310A and 310B are driven to rotate at a constant speed, the surfaces of the rotating bodies 310A and 310B, that is, the rotational speed of the provided cleaning member 31 is not constant. , Speed unevenness, that is, peripheral speed fluctuation occurs. The present inventor considered that the vibration is further amplified by the peripheral speed fluctuation.

  In the image reading apparatus 100, the first reading unit 102A and the second reading unit 102B are arranged on one conveyance path. Therefore, when a plurality of documents are conveyed continuously, the second reading on the upstream side is performed. The cleaning operation may be performed in the first reading unit 102A on the downstream side while the reading operation of the preceding document is performed in the unit 102B, and vice versa.

  As shown in FIG. 1, the image reading apparatus 100 includes a rotating body 310 </ b> A for cleaning the reading glass 215 of the first reading unit 102 </ b> A and the second reading unit 102 </ b> B in the ADF unit 101. When the reading operation is performed in one reading unit and the cleaning operation is performed in the other reading unit, the generated vibration propagates in the ADF unit 101 and the one reading unit in which the reading operation is performed is performed. Vibration propagates to the part. In addition, when a plurality of originals are conveyed continuously, vibration generated between the conveyed originals and the originals may continue until the next original reading operation. If the reading glass 215 vibrates when the conveyed original reaches the reading position 211, the original conveyed on the reading glass 215 vibrates, and the distance from the light source 206, the mirror group 207, and the lens 208 are affected. The distance to the CCD sensor 209 thus changed dynamically. Similarly, if the second reading unit 102B vibrates when the conveyed document reaches the reading position 306, the distance between the conveyed document and the CMOS sensor 303 of the light source 301 changes dynamically. It will be. As described above, the present inventor considered that there is an influence of the vibration generated in the cleaning operation as one factor of the quality deterioration of the read image.

  In particular, since the CIS method employed in the second reading unit 102B has a shallower depth of focus than the CCD method employed in the first reading unit 102A, the vibration of the second reading unit 102B itself and the document The influence of the change in the gap on the quality of the read image is serious. In light of the recent increase in the number of image reading apparatuses adopting the CIS method in accordance with the recent miniaturization of image reading apparatuses and the development of double-sided simultaneous reading apparatuses, the present inventor considered that the vibration generated in the cleaning operation is a read image. It was considered that it was likely to cause quality degradation. Therefore, the image reading apparatus 100 includes a configuration for suppressing vibrations of members in the ADF unit 101 that are generated by the cleaning operation.

  A first specific example of the configuration for suppressing the vibration of the members in the ADF unit 101 is the configuration shown in FIG. 6 provided in the second reading unit 102B. That is, referring to FIG. 6, in the second reading unit 102 </ b> B disposed in the ADF unit 101, the second reading unit 102 </ b> B is lifted upward in the drawing by the contact of the rotating body 310 </ b> B with the reading glass 302. Therefore, the second reading unit 102B is rotated between the surface of the second reading unit 102B far from the reading glass 302 and the ADF unit 101 casing or a portion bonded to the casing. As an elastic member for absorbing the force by which the second reading unit 102B is lifted by pressing in the direction toward 310B, for example, the spring 51 and as a member for absorbing the force by which the second reading unit 102B is lifted For example, a damper 52 is provided. Instead of the spring 51 and the damper 52, rubber, a urethane member, or the like may be used. Further, only one of the spring 51 and the damper 52 may be used. Alternatively, a plurality of springs (elastic members) may be used, and a plurality of dampers (members for absorbing force) may be used. Furthermore, a plurality of types of elastic members may be used, or a member for absorbing a plurality of types of forces may be used.

  The spring 51 and the damper 52 have a force F that presses the second reading unit 102B in the direction toward the rotating body 310B, and the positional relationship (orientation) between the second reading unit 102B and the rotating body 310B is shown in FIG. In the case shown, the force in the direction of lifting the second reading unit 102B, that is, the force due to the contact of the rotating body 310B in the cleaning operation, which is the force acting in the direction away from the rotating body 310B, is Fr. The spring constant and the damping force are set so that F> Fs + Fr−Fc, where Fs is the force acting on the sheet due to the contact and Fc is the weight of the second reading unit 102B itself. By doing so, the fluctuation component due to the rotating operation of the rotating body 310B can be absorbed by the spring 51 and the damper 52.

  The example of FIG. 6 is an example of a configuration for suppressing vibration generated in the second reading unit 102 </ b> B as a member in the ADF unit 101. Similarly, a configuration for suppressing vibration generated in the rotating body 310A facing the first reading unit 102A as a member in the ADF unit 101 is provided for the rotating body 310A. That is, as shown in FIG. 1, the positional relationship (direction) between the first reading unit 102A and the rotating body 310A is opposite to the positional relationship (direction) between the second reading unit 102B and the rotating body 310B. As for the first reading unit 102A, similarly to the configuration illustrated in FIG. 6, the elastic member for pressing the rotating body 310A in the direction toward the first reading unit 102A and the force for lifting the rotating body 310A are used. A member for absorbing is provided. This configuration for absorbing vibration is provided in at least one of the first reading unit 102A and the second reading unit 102B, and preferably in both. More preferably, at least the second reading unit 102B is provided.

  By providing the configuration shown in the first specific example, vibration generated in the members in the ADF unit 101 of each reading unit can be efficiently suppressed, and the reading unit and the original can be read at the time of reading unit vibration or original reading. The change in the gap with the can be suppressed. Thereby, deterioration of the quality of the read image can be suppressed. In particular, in the second reading unit 102B adopting the CIS method, the configuration according to the first specific example as shown in FIG. 6 is suitable for suppressing deterioration of the quality of the read image.

  As a second specific example of the configuration for suppressing the vibration of the members in the ADF unit 101, there is a document conveyance control in the drive control unit 502 as shown in the time chart of FIG. More specifically, referring to the time chart of FIG. 7, the first reading unit 102A is transported to the reading position 211 by feeding the preceding document under the control of the conventional drive control unit 502 shown in the time chart TC ′. When the original reading operation R11 is executed and the subsequent original is conveyed so as to reach the reading position 211 after a predetermined time Int1 from the arrival of the preceding original, the original reading operation R12 is executed. The drive control unit 502 causes the cleaning operation Sw11 to be executed between the reading operation R11 and the reading operation R12. At this time, if the same control as shown in the time chart TC2 is performed for the second reading unit 102B, the reading operation R2 is being executed in the second reading unit 102B as shown by the hatched area in the figure. In addition, the cleaning operation Sw11 in the first reading unit 102A is executed, which leads to quality deterioration of the read image obtained by the reading operation during that period. Similarly, as indicated by the hatched area in the figure, the cleaning operation Sw2 in the second reading unit 102B is executed during the execution of the reading operation R12 in the first reading unit 102A. This leads to quality degradation of the read image obtained by the reading operation during the period.

  Therefore, as a second specific example of the configuration for suppressing the vibration of the members in the ADF unit 101, the drive control unit 502 is a time for preventing an overlap between the reading operation and the cleaning operation represented by the hatched area in the drawing. Control represented by chart TC1 is performed. In other words, the drive control unit 502 continuously sets the interval between the originals conveyed to the first reading unit 102A until the cleaning operation Sw2 between the reading operations in the second reading unit 102B is completed. The transport roller group is controlled so that Int2 is longer than Int1. Preferably, the drive control unit 502 is a motor that is a drive mechanism of the rotating body 310A so that the cleaning operation Sw11 in the first reading unit 102A is executed at substantially the same timing as the cleaning operation Sw2 in the second reading unit 102B. The operation of 234A etc. is controlled.

  By performing such control, as shown in FIG. 7, the period in which the cleaning operation is executed in one reading unit and the period in which the reading operation is executed in the other reading unit do not overlap, The influence of the vibration of the member in the ADF unit 101 generated by the cleaning operation on the reading operation in the reading unit can be suppressed. Thereby, quality degradation of the read image can be suppressed.

  In FIG. 7 and the above description, the control for increasing the interval between the documents conveyed to the first reading unit 102A is shown. However, the control for increasing the interval between the documents conveyed to the second reading unit 102B is also performed. Image quality deterioration can be suppressed.

  As a specific example of the configuration for suppressing the vibration of the members in the ADF unit 101, the first specific example and the second specific example described above may be combined. By doing in this way, the vibration of the member in the ADF part 101 can be suppressed more, and the quality deterioration of the read image can be suppressed.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  31 Cleaning member, 32 White reference plane, 51 Spring, 52 Damper, 100 Image reading device, 101 ADF unit, 102A First reading unit, 102B Second reading unit, 200 Document tray, 206 Light source, 207 Mirror group, 208 Lens, 209 CCD sensor, 211 reading position, 212 transport roller, 214 discharge tray, 215 reading glass, 217 paper feed sensor, 234A, 234B motor, 301 light source, 302 reading glass, 303 CMOS sensor, 304 guide, 306 reading position, 310A, 310B Rotating body, 312 sensor, 331 sprocket, 332 output sprocket, 333 timing belt, 500 control unit, 501 image processing unit, 502 drive control unit, 600 memory, 700 image forming unit.

Claims (15)

First reading means;
An automatic document feeder provided relative to the first reading means,
The automatic document feeder includes:
Transport means for transporting documents one by one;
Position relative to the first transparent member for cleaning the first transparent member provided at a position corresponding to the reading position of the first reading means on the transport path in the transport means by a cleaning operation. A first cleaning means provided in the
A surface opposite to the first reading unit with respect to the document conveyed on the conveyance path, and a surface opposite to the surface read by the first reading unit of the conveyed document; A second reading means for optically reading through a second transparent member on the transport path;
A second cleaning means provided at a position opposite to the second transparent member for cleaning the second transparent member by a cleaning operation;
Together is disposed in front Stories second reading hand stage and a absorbing means for absorbing the fluctuation component due to the cleaning operation,
The absorbing means has the following relationship as a force F that presses the second reading means toward the second cleaning means:
F> Fs + Fr−Fc
(However,
Fr: force in a direction in which the second reading unit is lifted by the contact of the second cleaning unit in a cleaning operation;
Fc: dead weight of the second reading means,
Fs: force acting on the second reading unit by a paper scraper when the document comes into contact)
An image reading apparatus that generates a force F satisfying Each of the first cleaning means and the second cleaning means has a configuration in which a cleaning member is added to a rotating body,
The cleaning operation is an operation of rotating the rotating body,
The image reading apparatus according to claim 1, wherein the cleaning member comes into contact with the first transparent member or the second transparent member by the cleaning operation. The image reading apparatus according to claim 2 , wherein a part of the rotating body constitutes a part of the transport path.   4. The image reading apparatus according to claim 2, wherein the first cleaning unit and the second cleaning unit have different rotation centers and center-of-gravity positions. 5. The absorbing means is a spring, an image reading apparatus according to any one of claims 1-4. The absorbing means is a damper, the image reading apparatus according to any one of claims 1-4. Said first reading means includes a CCD (Charged Coupled Device), the second reading means comprises a CIS (Contact Image Sensor), image reading apparatus according to any one of claims 1-6. An image reading apparatus according to any one of claims 1 to 7, an image forming apparatus. Transport means for transporting documents one by one;
Provided at a position opposite to the first transparent member for cleaning the first transparent member provided at a position corresponding to the reading position of the reading device on the conveying path in the conveying means by a cleaning operation. First cleaning means,
Provided on the surface opposite to the surface on the reading device side with respect to the document conveyed on the conveyance path, the surface opposite to the surface read by the reading device of the conveyed document on the conveyance path Reading means for optically reading through the second transparent member;
A second cleaning means provided at a position opposite to the second transparent member for cleaning the second transparent member by a cleaning operation;
Placed before Symbol reading hand stage and a absorbing means for absorbing the fluctuation component due to the cleaning operation,
The absorbing means has the following relationship as a force F that presses the reading means toward the second cleaning means:
F> Fs + Fr−Fc
(However,
Fr: force in a direction in which the reading means is lifted by contact of the second cleaning means in a cleaning operation;
Fc: the weight of the reading means,
Fs: force acting on the reading means by a paper scraper when the document comes into contact)
Der which produces a force F that satisfies Ru, automatic document feeder. Each of the first cleaning means and the second cleaning means has a configuration in which a cleaning member is added to a rotating body,
The cleaning operation is an operation of rotating the rotating body,
The automatic document feeder according to claim 9 , wherein the cleaning member comes into contact with the first transparent member or the second transparent member by the cleaning operation. The automatic document feeder according to claim 10 , wherein a part of the rotating body constitutes a part of the transport path. The automatic document feeder according to claim 10 or 11 , wherein the first cleaning means and the second cleaning means have different rotation centers and center-of-gravity positions. The automatic document feeder according to any one of claims 9 to 12 , wherein the absorbing means is a spring. The absorbing means is a damper, an automatic document feeder according to any one of claims 9-12. It said reading means includes a CIS (Contact Image Sensor), automatic document feeder according to any one of claims 9-14.

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