JP2010004098A - Image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent incomplete cleaning due to deterioration in deformation state by detecting the deformation state of a cleaning brush used for cleaning a reading glass. <P>SOLUTION: A cleaning member 41 having a cleaning brush 43 is disposed in a position opposite a reading glass 21 with an original document transfer path of the image reading apparatus 4 sandwiched therebetween, and the cleaning member 41 operates in a predetermined rotation direction R1, thereby causing the cleaning brush 43 to clean the surface of the reading glass 21. When a position detecting sensor 45 detects that the rotation position of the cleaning brush 43 is a predetermined position, a drive current of the motor M1 for driving the rotation of the cleaning member 43 is read in response to that, and the deformation state of the cleaning brush 43 is detected based on the driving current. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image reading apparatus, and more particularly, to an image reading apparatus that conveys originals one by one onto a reading glass surface and performs image reading when the original passes a reading position on the reading glass surface. .

  2. Description of the Related Art Conventionally, an image reading apparatus provided with a so-called sheet-through type automatic document feeder is known. In this type of apparatus, the automatic document feeder conveys documents one by one onto the reading glass surface, and when the document passes through a predetermined reading position on the reading glass surface, the image reading unit captures an image of the document. It is configured to read.

  In such an image reading apparatus, if foreign matter such as paper dust adheres to the surface of the reading glass, the foreign matter appears as streak noise in the read image. For this reason, various methods have been proposed in order to eliminate the influence of foreign matter on the surface of the reading glass. Among them, for example, there is a method of removing a foreign substance from the surface of the reading glass by disposing a cleaning member provided with a brush or the like on the reading glass surface and driving the cleaning member to clean the glass surface (for example, Patent Documents 1 and 2).

JP-A-6-164863 JP 2000-270152 A

  By the way, when the surface of the reading glass is cleaned with a cleaning brush, the operation direction of the cleaning brush is usually always the same as the conveying direction of the document conveyed on the reading glass surface. Therefore, by repeatedly performing the cleaning operation, the cleaning brush is bent and deformed in a certain direction. If this is left unattended, the deformed state further deteriorates, and the cleaning brush does not come into good contact with the reading glass. For this reason, there is a problem that cleaning becomes poor and the rate at which streak noise appears in the read image increases.

  Accordingly, the present invention has been made to solve the above-described conventional problems, and by detecting the deformation state of the cleaning brush, it is possible to prevent an image reading that can prevent the deformation state from deteriorating and causing poor cleaning. An object of the present invention is to provide an image reading apparatus capable of improving the cleaning performance of the cleaning brush by correcting the deformation state of the cleaning brush.

  In order to achieve the above object, according to the first aspect of the present invention, an original is conveyed one by one on the reading glass surface, and image reading is performed when the original passes the reading position on the reading glass surface. A cleaning brush that is disposed opposite to the reading glass with a document conveyance path interposed therebetween and that moves in a predetermined rotation direction to contact the reading glass and clean the surface of the reading glass. And a control means for controlling the cleaning operation of the cleaning brush, and a position detection means for detecting the rotational position of the cleaning brush, wherein the control means determines the deformation state of the cleaning brush caused by repeated cleaning operations. It is characterized by detection.

  According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, the control unit responds to the fact that the position detecting unit detects that the rotational position of the cleaning brush is a predetermined position. Then, information that changes with the deformation of the cleaning brush is acquired, and the deformation state of the cleaning brush is detected based on the information.

  According to a third aspect of the present invention, in the image reading apparatus according to the first or second aspect, the control means causes the cleaning brush to be deformed during the cleaning operation of the cleaning brush.

  According to a fourth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the driving unit that drives the cleaning brush in the rotational direction, and the driving unit that drives the cleaning brush. Current detection means for detecting a drive current of the current detection means, wherein the control means detects the current detection in response to the position detection means detecting that the rotational position of the cleaning brush is a predetermined position. The deformation state of the cleaning brush is detected based on the drive current of the drive means detected by the means.

  According to a fifth aspect of the present invention, in the image reading apparatus according to the fourth aspect, the predetermined position is a position where the cleaning brush contacts the reading glass.

  According to a sixth aspect of the present invention, in the image reading apparatus according to the fourth aspect, the foreign matter attached to the cleaning brush during the cleaning operation is provided on the downstream side in the rotational direction of the cleaning brush from the cleaning brush. Further, the cleaning device further includes a foreign material cleaning unit that scrapes off, and the predetermined position is a position where the cleaning brush and the foreign material cleaning unit are in contact with each other.

  According to a seventh aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the foreign matter provided on the downstream side in the rotational direction of the cleaning brush and attached to the cleaning brush during a cleaning operation. A foreign matter scraping means for scraping off the cleaning brush from the cleaning brush, and a vibration detecting means for detecting a vibration when the foreign matter scraping means comes into contact with the cleaning brush to scrape the foreign matter from the cleaning brush, In response to detecting that the rotational position of the cleaning brush is in contact with the cleaning brush by the position detecting means, the control means detects the vibration of the foreign matter scraping means detected by the vibration detecting means. The deformation state of the cleaning brush is detected based on the width.

  According to an eighth aspect of the present invention, in the image reading apparatus according to any one of the first to third aspects, the cleaning brush is rotated when the cleaning brush is rotated in the rotational direction in a state where the cleaning brush is not deformed. The apparatus further comprises density level measuring means for reading an image at a contact start position where the brush and the reading glass first contact each other, and detecting the density level of the read image, and the control means uses the position detecting means to detect the cleaning brush. In response to detecting that the rotation position is the contact start position, the deformation state of the cleaning brush is detected based on the density level detected by the density level measuring means.

  According to a ninth aspect of the present invention, in the image reading apparatus according to the eighth aspect of the present invention, the image reading apparatus includes a read head provided corresponding to the read position, and reads an image at the read position via the read head. And a moving means for moving the reading head, the moving means moving the reading position to the contact start position by moving the reading head, and the image reading means. Can be used as the concentration level measuring means.

  According to a tenth aspect of the present invention, in the image reading apparatus according to any one of the first to ninth aspects, when the cleaning brush is deformed, the control means moves the cleaning brush in a direction opposite to the rotation direction. It is characterized by being rotated a predetermined number of times in the direction.

  According to an eleventh aspect of the present invention, in the image reading apparatus according to any one of the first to ninth aspects, when the cleaning brush is deformed, the control means presses the deformation direction side with a predetermined member. The cleaning member is stopped as an attached state.

  According to the image reading apparatus of the present invention, when the cleaning brush is bent and deformed in a certain direction by repeatedly performing the cleaning operation with the cleaning brush, the deformation state of the cleaning brush can be detected. Therefore, it is possible to prevent the cleaning brush from being left in a deformed state, and to prevent deterioration of the deformed state. In particular, when the cleaning brush is deformed, the cleaning member is rotated by a predetermined number of times in the direction opposite to the cleaning direction, or the cleaning member is pressed with a predetermined member on the deformation direction side of the cleaning brush. Since the cleaning brush which deform | transformed can be correct | amended by making it stop, it is possible to improve the cleaning performance of a cleaning brush.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected about the member which is mutually common in some embodiment demonstrated below, and the description which repeats about them is abbreviate | omitted.

  (First embodiment)

  FIG. 1 is a perspective view illustrating an example of an external configuration of an image processing apparatus 1 having an image reading function. The image processing apparatus 1 is a so-called multifunction device or MFP, and has a plurality of functions such as a copy function, a FAX function, a printer function, and a scanner function. The image processing apparatus 1 can be connected to a network such as a LAN, and can also be connected to a communication network such as a telephone line. The image data read from the original can be output to another computer via the network, or the image data can be input from another computer via the network, and the print output can be performed based on the image data. Yes. In addition, FAX data can be transmitted and received via a communication network.

  The image processing apparatus 1 includes an image reading device 4 including a scanner unit 2 and an automatic document feeder (so-called ADF) 3 on an upper portion of the apparatus main body 1a. The image reading device 4 operates the automatic document feeder 3 and the scanner unit 2 in synchronization with each other so as to read images one by one from the document set on the automatic document feeder 3 and output image data. It is configured. More specifically, the automatic document feeder 3 is configured to convey documents one by one toward the scanner unit 2, and the scanner unit 2 reads an image while the document passes a predetermined reading position. And is configured to generate image data.

  A sheet feeding unit 6 is provided inside the lower part of the apparatus main body 1a of the image processing apparatus 1, and an image forming unit 5 is further provided on the upper part. The paper feed unit 6 accommodates paper as an image forming medium and supplies the paper to the image forming unit 5 one by one. The image forming unit 5 is an image forming unit that forms an image on the basis of input image data. The image forming unit 5 forms an image on a sheet supplied from the sheet feeding unit 6 based on the input image data, and performs print output. Configured to do. For example, in the case of a copy function, the image forming unit 5 performs image formation based on image data input from the image reading device 4, so that the image processing device 1 outputs a copy of the read document.

  On the front side (front side) of the apparatus main body 1a of the image processing apparatus 1, an operation panel 10 that can be operated by the user is provided. A user selects a function to be used from among a plurality of functions of the image processing apparatus 1 by performing a key operation while looking at a guidance screen displayed on the operation panel 10, and various setting operations relating to the selected function. In addition, the image processing apparatus 1 can be instructed to execute a job.

  FIG. 2 is a schematic diagram showing the overall internal configuration of the image reading apparatus 4. The automatic document feeder 3 includes a paper feed tray 31 on which the documents 9 are stacked, and the document 9 set on the paper feed tray 31 is taken out one by one and conveyed by the conveyance mechanism provided inside the apparatus. It is configured. The automatic document feeder 3 includes a pickup roller 32 and a plurality of transport rollers 33 and 36 as a transport mechanism for transporting documents one by one. The pick-up roller 32 takes out only the uppermost document from the documents 9 stacked on the paper feed tray 31 and supplies it to the transport roller 33.

  The conveyance roller 33 conveys the document fed by the pickup roller 32 along the first conveyance path 34 and conveys the document to the document reading unit 35 provided corresponding to the reading glass 21 of the scanner unit 2. When the document conveyed to the document reading unit 35 passes through a predetermined reading position on the reading glass 21, the image is read by the scanner unit 2. Then, the document that has passed through the document reading unit 35 is transported through the second transport path 37 by the transport roller 36 and is discharged to the document discharge unit 39 through the discharge port 38. In addition to the above-described conveyance paths 34 and 37, the automatic document conveyance device 3 is additionally provided with a conveyance path for reversing the document in the case of a double-sided document, but this is not illustrated.

  The scanner unit 2 includes a transparent reading glass 21 provided on the upper surface thereof for reading an image of a document. An image reading unit for reading an image through the reading glass 21 is provided inside the scanner unit 2. More specifically, an exposure device 22 for exposing a document passing through a predetermined reading position is provided inside the scanner unit 2, and reflected light from the document exposed by the exposure device 22 is reflected from the exposure device 22. Then, the light is guided into the scanner unit 2 through the reading glass 21 and passes through a plurality of mirrors 23 and lenses 24 to form an image on an image reading unit 25 such as a CCD. Here, the exposure device 22 and the plurality of mirrors 23 are assembled into a unit by being assembled to a reading head 29 provided corresponding to the reading position. Therefore, in other words, the installation position of the reading head 29 defines the reading position of the document that passes through the upper surface of the reading glass 21. The image reading unit 25 is configured to generate an image signal by detecting a density level corresponding to the amount of light of each of R, G, and B color components incident via the reading glass 21 and the reading head 29. The image signal is output to the image processing unit 26. The image processing unit 26 A / D converts the image signal input from the image reading unit 25 and performs various image processing to generate image data.

  In the present embodiment, a glass surface cleaning mechanism 40 is provided in the document reading section 35 of the automatic document feeder 3 so as to face the reading glass 21 with the document conveyance path interposed therebetween. The glass surface cleaning mechanism 40 is configured to perform a cleaning operation on the upper surface of the reading glass 21 in a state where no document is conveyed, and to remove foreign matters such as paper dust attached to the upper surface of the reading glass 21. For example, when the automatic document feeder 3 continuously conveys a plurality of documents 9, the glass surface cleaning mechanism 40 causes the preceding document to pass through the image reading unit 35 and then the next document to the image reading unit. The cleaning operation is performed at an interval between the originals until the paper is conveyed to 35.

  FIG. 3 is an enlarged view showing a configuration of a portion where the glass surface cleaning mechanism 40 is provided. A document conveyed by the automatic document conveyance device 3 is conveyed along the conveyance direction F on the upper surface of the reading glass 21, and when the document passes immediately above the reading position 20, an image is read by the scanner unit 2. The glass surface cleaning mechanism 40 is provided above the reading glass 21 corresponding to the reading position 20.

  The glass surface cleaning mechanism 40 includes a cleaning member 41 that is operated by a motor M1. The cleaning member 41 has a substantially cylindrical roller member 42 that is supported so as to be rotatable in both forward and reverse directions with respect to the rotation shaft 42a, and a part of the roller member 42 in the circumferential direction is substantially flat. The cleaning brush 43 is configured by a brush holding surface, and a large number of brush hairs are implanted on the brush holding surface. Further, the peripheral surface of the roller member 42 where the cleaning brush 43 is not implanted is a white roller surface. Further, the length of the cleaning brush 43 is a length that can clean the upper surface of the reading glass 21 when the cleaning member 41 rotates. In the illustrated example, the cleaning brush 43 is directly planted on the roller member 42. However, the cleaning brush 43 and the roller member 42 may be detachable, and only the cleaning brush 43 may be replaced.

  For example, as shown in FIG. 3, the cleaning member 41 has a normal home position (standby position) with the cleaning brush 43 facing upward, and when the document is passing through the upper surface of the reading glass 21, Wait at home position. At a timing at which the upper surface of the reading glass 21 can be cleaned, the cleaning member 41 is driven by the motor M1 and rotates in the rotation direction R1 that is the normal rotation direction. Thereby, the cleaning brush 43 is also rotated in the rotation direction R1, and the cleaning operation is started. In this cleaning operation, the cleaning brush 43 comes into contact with the upper surface of the reading glass 21 and rotates in the rotation direction R1, thereby sweeping out foreign matters such as paper dust on the upper surface of the reading glass 21, thereby reading the reading position 20. Remove foreign material from Here, the rotation direction R1 of the cleaning member 41 is set so that the cleaning direction by the cleaning brush 43 is the same as the document transport direction F. Therefore, the cleaning member 41 sweeps out the foreign matter on the upper surface of the reading glass 21 toward the downstream side in the transport direction F.

  A part of the foreign matter removed from the reading position 20 of the reading glass 21 is swept away to the downstream side of the reading position 20, and the other part adheres to the cleaning brush 43. If the foreign matter adhering to the cleaning brush 43 is left as it is, the foreign matter adhering to the cleaning brush 43 may adhere to the reading glass 21 again at the next cleaning. For this reason, it is necessary to remove foreign matter adhering to the cleaning brush 43 by the cleaning operation as described above from the cleaning brush 43. Therefore, in the present embodiment, in order to remove the foreign matter adhering to the cleaning brush 43, the foreign matter scraper is disposed at a position where it can come into contact with the cleaning brush 43 of the rotating cleaning member 41 on the downstream side in the rotation direction R <b> 1 of the cleaning member 41. A take-up member 50 is provided. The foreign material scraping member 50 is formed of, for example, a flat plate or blade-shaped member, and scrapes foreign matter from the cleaning brush 43 that has cleaned the upper surface of the reading glass 21 by contacting the cleaning brush 43 during rotation. Is. Therefore, when the cleaning member 41 rotates in the rotation direction R1, the cleaning brush 43 and the reading glass 21 first come into contact with each other to perform the cleaning operation of the reading glass 21, and then the cleaning brush 43 and the reading glass 21 are separated from each other. Next, the cleaning brush 43 and the foreign matter cleaning member 50 come into contact with each other to remove foreign matter attached to the cleaning brush 43, and the cleaning brush 43 can be returned to the home position in a clean state where no foreign matter is attached. .

  A position detection sensor 45 that detects the rotational position of the roller member 42 is provided in the vicinity of the cleaning member 41. The position detection sensor 45 is provided, for example, at a position deviating from the image reading width in the main scanning direction by the scanner unit 2, and detects the marking attached to the peripheral surface of the roller member 42 to turn on / off the roller. In this configuration, it is possible to detect that the member 42 has reached a predetermined rotational position. According to this position detection sensor 45, the rotational position of the cleaning brush 43 is also detected. In the case of the present embodiment, the rotational position detected by the position detection sensor 45 is set to either the position where the cleaning brush 43 contacts the reading glass 21 or the position where the cleaning brush 43 contacts the foreign material scraping member 50. The Although the position detection sensor 45 is shown above the cleaning member 41 in the illustrated example, the installation position is not particularly limited as long as it is in the vicinity of the cleaning member 41.

  4 to 6 are diagrams showing the flow of the cleaning operation by the cleaning brush 43. FIG. First, as shown in FIG. 4A, when the preceding document 9a passes over the upper surface of the reading glass 21, the cleaning member 41 is in a standby state at the home position, and the cleaning brush 43 is removed from the document conveyance path. Evacuated. FIG. 4A shows a case where foreign matter G such as paper dust adheres to the upper surface of the reading glass 21. When the trailing end of the preceding document 9a passes a predetermined position in the conveyance path, the cleaning member 41 is driven to rotate as shown in FIG. 4B, and the cleaning brush 43 starts rotating in the rotation direction R1. .

  When the trailing edge of the preceding document 9a is conveyed downstream from the upper surface of the reading glass 21, the cleaning member 41 brings the cleaning brush 43 into contact with the upper surface of the reading glass 21, as shown in FIG. Then, cleaning of the reading glass 21 is started. The cleaning brush 43 removes the foreign matter G on the upper surface of the reading position 20 of the reading glass 21 while sweeping the upper surface of the reading glass 21 so as to follow the trailing edge of the preceding document 9a. At this time, a part of the foreign matter G to be removed adheres to the cleaning brush 43. When the cleaning member 41 further rotates and the cleaning brush 43 moves away from the reading glass 21, the cleaning brush 43 comes into contact with the foreign material scraping member 50 as shown in FIG. The foreign material scraping member 50 scrapes the foreign matter G adhering to the cleaning brush 43 and removes it from the cleaning brush 43 by making contact with the cleaning brush 43 that is rotating. Thereafter, as shown in FIG. 6, the cleaning member 41 stops when it rotates to the home position. The foreign matter G scraped off by the foreign matter cleaning member 50 naturally falls below the foreign matter cleaning member 50 and accumulates on the downstream side of the reading position 20 in the document conveyance path. The foreign object G adheres to the original 9b and is discharged to the outside of the automatic original conveying apparatus 3 as the next original 9b is conveyed.

  As described above, when the cleaning member 41 rotates once in the rotation direction R1, the cleaning brush 43 sweeps away the foreign matter adhering to the upper surface of the reading glass 21 and removes it from the reading position 20 once. Foreign matter adhering to the cleaning brush 43 during the cleaning operation can also be removed. Then, such a cleaning operation is repeatedly performed in the image reading device 4, whereby the cleaning brush 43 is bent and deformed in a certain direction.

  Next, the control mechanism of the image reading device 4 will be described. FIG. 7 is a block diagram showing a control mechanism for mainly controlling the image reading device 4 in the image processing apparatus 1. The image processing apparatus 1 is provided with a main control unit 10, and the main control unit 10 controls the scanner unit 2 and the automatic document feeder 3 in an integrated manner. For example, when the user instructs the operation panel 7 to start reading a document, the main control unit 10 responds to the reading start instruction input from the operation panel 7 and the ADF control unit 11 and the scanner of the automatic document feeder 3. A command for starting a document reading operation is output to the scanner control unit 12 of the unit 2.

  The ADF control unit 11 and the scanner control unit 12 are connected so as to be able to communicate with each other. When a command for instructing the start of document reading is input from the main control unit 10, timing information such as document conveyance timing and image reading timing is provided. In addition, by controlling each unit while exchanging other information with each other, the automatic document feeder 3 and the scanner unit 2 perform synchronized operations.

  The ADF control unit 11 includes a CPU 11a and a memory 11b. The CPU 11a executes processing based on a predetermined program, thereby controlling operation of each unit provided in the automatic document feeder 3. Function. For example, the ADF control unit 11 controls the document conveyance driving unit 13 for driving the conveyance mechanism including the pickup roller 32, the conveyance roller 33, the conveyance roller 36, and the like described above, so that the document in the automatic document conveyance device 3 is controlled. Control is performed so that the conveying operation is synchronized with the image reading operation of the scanner unit 2. Further, the ADF control unit 11 controls the glass surface cleaning mechanism 40 and controls the cleaning operation by the cleaning brush 43 described above.

  The glass surface cleaning mechanism 40 includes a motor drive unit 47 and a motor M1 as a configuration for driving the cleaning member 41 described above, and a position detection sensor 45 that detects the rotational position of the cleaning member 41. For example, a DC motor is used as the motor M1. When the ADF control unit 11 outputs a pulse signal for driving the motor M1 to the motor driving unit 47, the motor driving unit 47 sends a driving current to the motor M1 to drive the motor M1 based on the pulse signal. . Therefore, the motor M <b> 1 is activated when a driving current is supplied from the motor driving unit 47. The motor drive unit 47 is provided with a current detection circuit 48 that detects this drive current, and the current value detected by the current detection circuit 48 is output to the ADF control unit 11. The position detection sensor 45 is turned on when the rotation position of the cleaning member 41 is a predetermined position, and outputs a signal to the ADF control unit 11.

  The scanner control unit 12 includes a CPU 12a and a memory 12b, and controls the operation of each unit provided in the scanner unit 2 when the CPU 12a executes processing based on a predetermined program. That is, the scanner control unit 12 performs data communication with the ADF control unit 11 so as to perform an image reading operation in synchronization with the document conveyance operation in the automatic document conveyance device 3, and the exposure device 22 and the image reading unit 25. And controls each unit of the image processing unit 26.

  In the above configuration, the ADF control unit 11 is further configured to detect a deformed state of the cleaning brush 43 caused by repeating the cleaning operation. More specifically, if the cleaning brush 43 is in an initial state where it is not deformed, the frictional force between the cleaning brush 43 and the reading glass 21 when the cleaning brush 43 is in contact with the reading glass 21 and performing a cleaning operation. The load on the motor M1 increases accordingly. On the other hand, when the cleaning brush 43 is gradually deformed, the frictional force between the cleaning brush 43 and the reading glass 21 during the cleaning operation is reduced, and the load applied to the motor M1 is accordingly reduced. And if the load concerning motor M1 fluctuates, the drive current at the time of driving motor M1 will fluctuate with it. That is, if the load applied to the motor M1 is large, the drive current when driving the motor M1 is large, whereas if the load applied to the motor M1 is small, the drive current is small. Therefore, in the present embodiment, the driving current of the motor M1 is used as information that changes as the cleaning brush 43 is deformed, and the ADF control unit 11 is based on the current value input from the current detection circuit 48. The deformation state of is detected.

  FIG. 8 is a diagram showing a change characteristic of the drive current of the motor M1 during the cleaning operation by the cleaning brush 43. As shown in FIG. Assuming that the motor M1 starts to be started at the time T0 to start the cleaning operation, the drive current changes as indicated by La in the drawing, and a large starting current temporarily flows through the motor M1 immediately after the start. The activation region R1 through which this activation current flows is from time T0 to T1, and after time T1, the drive current is stabilized. In this stable region R2, the drive current changes according to the load applied to the motor M1, so that when the cleaning brush 43 and the reading glass 21 come into contact with each other and a frictional force is applied, a current corresponding thereto is obtained.

  FIG. 9 is a diagram illustrating the drive current of the motor M1 that changes according to the deformation state of the cleaning brush 43. In the drawing, the drive current La1 indicates the drive current when the motor M1 is driven and the cleaning operation is performed in the initial state where the cleaning brush 43 is not deformed. In this state, the frictional force between the cleaning brush 43 and the reading glass 21 is large and the load applied to the motor M1 is also large, so that the driving current La1 when the cleaning brush 43 is in contact with the reading glass 21 is large. When the cleaning brush 43 is gradually deformed by repeating the cleaning operation, the drive current gradually decreases from La1 to La2, La3, and La4.

  Therefore, in the present embodiment, as shown in FIG. 9, the position detection sensor 45 is turned on at the timing Ts when the driving current La is in the stable region R2 and the cleaning brush 43 and the reading glass 21 are in contact with each other. It is configured as follows. The ADF control unit 11 reads the current value output from the current detection circuit 48 at the timing Ts when the position detection sensor 45 is turned on, and determines the deformation state of the cleaning brush 43 based on the current value.

  A plurality of threshold values TA1, TA2, and TA3 (TA1> TA2> TA3) for determining the deformation stage of the cleaning brush 43 are stored in the memory 11b of the ADF control unit 11 in advance. The deformation value of the cleaning brush 43 is determined by comparing the current value acquired from the detection circuit 48 with the threshold values TA1, TA2, and TA3. For example, as shown in FIG. 9, if the current value acquired at the timing Ts when the position detection sensor 45 is turned on is Va1, the current value Va1 is larger than the threshold value TA1, so the cleaning brush 43 is not deformed in the initial stage. Judged to be in a state. When the current value acquired from the current detection circuit 48 is Va2, since the current value Va2 is smaller than the threshold TA1 and larger than the threshold TA2, the cleaning brush 43 is a first deformed state slightly deformed from the initial state. Judge that it is a stage. When the current value acquired from the current detection circuit 48 is Va3, the current value Va3 is smaller than the threshold value TA2 and larger than the threshold value TA3. Therefore, the cleaning brush 43 is in a deformed state further slightly deformed from the first stage. Judge that it is the second stage. Further, when the current value acquired from the current detection circuit 48 is Va4, the current value Va4 is smaller than the threshold value TA3, so that the cleaning brush 43 is determined to be in the third stage of the deformed state further deformed from the second stage. To do.

  Here, when the cleaning brush 43 is deformed, an example is shown in which the deformed state is detected in three stages, but this need not necessarily be in three stages, and may be in one stage. There may be two stages. Furthermore, it is good also as four steps or more.

  The position where the driving current La of the motor M1 changes according to the deformation state of the cleaning brush 43 is not only the position where the cleaning brush 43 and the reading glass 21 contact as described above, but also the cleaning brush 43 and the foreign material scraping member. There is also a position where 50 contacts. That is, in the initial state where the cleaning brush 43 is not deformed, the cleaning brush 43 and the foreign material cleaning member 50 when the cleaning brush 43 is in contact with the foreign material cleaning member 50 and the foreign object cleaning operation is performed. And the load applied to the motor M1 increases accordingly. On the other hand, when the cleaning brush 43 is gradually deformed, the frictional force between the cleaning brush 43 and the foreign material cleaning member 50 at the time of foreign matter cleaning decreases, and the load applied to the motor M1 also decreases accordingly. Therefore, the rotation position detected by the position detection sensor 45 may be a position where the cleaning brush 43 contacts the reading glass 21, but is not limited thereto, and may be a position where the cleaning brush 43 contacts the foreign material scraping member 50. .

  If it is detected that the cleaning brush 43 is deformed from the initial state by detecting the deformation state of the cleaning brush 43 as described above, for example, this is indicated to the user via the operation panel 7 or the like. If it is set as the structure which alert | reports, appropriate processes, such as exchanging the cleaning brush 43 for a new article, can be performed, and it can prevent leaving the cleaning brush 43 in the deformed state. Therefore, it is possible to prevent inadequate cleaning of the reading glass 21 due to further deterioration of the deformed state.

  Moreover, in this embodiment, when it turns out that the cleaning brush 43 is in the state which deform | transformed from the initial state as a result of detecting the deformation | transformation state of the cleaning brush 43, ADF control part 11 respond | corresponds to the step of the deformation | transformation state. The glass surface cleaning mechanism 40 is controlled to perform a correction operation for correcting the deformation of the cleaning brush 43.

  FIG. 10 is a diagram illustrating a first correction operation when the cleaning brush 43 is deformed. The first correction operation is an operation of rotating the cleaning brush 43 a predetermined number of times in the rotation direction R2 opposite to the rotation direction R1 during the cleaning operation. When the ADF control unit 11 outputs a pulse signal for driving the motor M1 in the direction opposite to that during the cleaning operation to the motor driving unit 47, the motor driving unit 47 performs a cleaning operation on the motor M1 based on the pulse signal. A drive current in the opposite direction to the time is passed. Accordingly, the motor M1 is driven in the opposite direction to that during the cleaning operation, and rotates the cleaning brush 43 in the rotation direction R2. By such a first correction operation, the cleaning brush 43 deformed in a certain direction by repeating the cleaning operation is deformed in the opposite direction, so that the deformation state of the cleaning brush 43 can be corrected. Here, the number of rotations in the rotation direction R2 opposite to the rotation direction R1 can be set as appropriate. However, in this embodiment, when the deformation state of the cleaning brush 43 is the first stage, N1 times (however, N1 ≧ 1) Reverse rotation driving is performed, and N2 times (where N2> N1) reverse rotation driving is performed in the second stage. That is, the number of rotations in the reverse direction is set to increase as the deformation state of the cleaning brush 43 deteriorates. Such a first correction operation may be performed at the timing when the cleaning operation by the cleaning brush 43 is completed, or may be performed at the timing when all the document conveying operations are completed.

  FIG. 11 is a diagram illustrating a second correction operation when the cleaning brush 43 is deformed. The second correction operation is a state in which a predetermined pressing member is pressed from the deformation direction side of the brush against the cleaning brush 43 deformed in a certain direction by repeating the cleaning operation, and the cleaning brush 43 is maintained by holding the state. This is a brazing operation for performing brazing to correct the deformed state. In the case of the illustrated example, the foreign material scraping member 50 is used as a pressing member that is pressed from the deformation direction side of the brush. Therefore, for example, after the cleaning brush 43 rotating in the rotation direction R1 passes through the foreign material scraping member 50 during the cleaning operation, the ADF control unit 11 reverses the cleaning brush 43 in the rotation direction R2 by a predetermined amount and returns it. Thus, the deformed brush tip of the cleaning brush 43 is pressed against the upper surface of the foreign material scraping member 50, and this state is maintained. By such a second correction operation, the cleaning brush 43 deformed in a certain direction by repeating the cleaning operation is brazed so as to return to the straight hair-like brush, so that the deformation state of the cleaning brush 43 is corrected. Can do. Here, the holding time in the brazed state in which the deformed brush tip of the cleaning brush 43 is pressed against the upper surface of the foreign material cleaning member 50 can be set as appropriate, and may be held for a predetermined time set in advance. In addition, the brazing state may be changed to the home position of the cleaning member 41 so that the brazing operation is always performed in a standby state where the cleaning operation is not performed. In the case of this embodiment, such a second correction operation is performed when the deformation state of the cleaning brush 43 is in the third stage. In the example of FIG. 11, the foreign material scraping member 50 is used as a pressing member that presses the brush from the deformation direction side of the cleaning brush 43, but the upper surface of the reading glass 21 may be used as a pressing member. Alternatively, a dedicated pressing member may be separately arranged.

  Next, a processing sequence for detecting and correcting the deformation state of the cleaning brush 43 in the image reading device 4 will be described. 12 and 13 are flowcharts showing a series of processing procedures by the ADF control unit 11, FIG. 12 shows the first half of the processing procedure, and FIG. 13 shows the second half of the processing procedure. This process is, for example, a process that is repeatedly executed by the ADF control unit 11 every predetermined time (for example, several milliseconds) when the automatic document conveying device 3 starts the conveying operation of the document 9, and even during the cleaning operation. This process is repeatedly executed. As shown in FIG. 12, the ADF control unit 11 first determines whether or not the cleaning member 41 is rotating (step S10). Here, when the cleaning member 41 is not operating (in the case of NO), since the cleaning operation is not being performed, this process is terminated. On the other hand, when the cleaning member 41 is operating (in the case of YES), the process proceeds to step S11.

  When the cleaning member 41 is performing the cleaning operation, the ADF control unit 11 determines whether or not the position detection sensor 45 is turned on (step S11). Here, if the position detection sensor 45 is off, the cleaning member 41 has not yet reached the rotational position where the deformation state of the cleaning brush 43 can be confirmed. . On the other hand, if the position detection sensor 45 is on, the cleaning member 41 has reached the rotational position where the deformation state of the cleaning brush 43 can be confirmed, so that the determination is YES, and the process proceeds to step S12.

  When the position detection sensor 45 is on, the ADF control unit 11 acquires the current value Va of the drive current driving the motor M1 from the current detection circuit 48 (step S12). The ADF control unit 11 compares the acquired current value Va with the threshold value TA1, and determines whether or not the current value Va is smaller than the threshold value TA1 (step S13). If the current value Va is equal to or greater than the threshold value TA1, the determination is NO and the process proceeds to step S14, where it is determined that the cleaning brush 43 is in an initial state that is not deformed. On the other hand, when the current value Va is smaller than the threshold value TA1, it is determined that the cleaning brush 43 is deformed.

  Then, the ADF control unit 11 determines whether or not the current value Va is smaller than the threshold value TA2 in order to specify the stage of the deformation state (step S15). If the current value Va is equal to or greater than the threshold value TA2, it is determined that the deformation state of the cleaning brush 43 is the first stage (step S16). On the other hand, if the current value Va is smaller than the threshold value TA2, it is further determined whether or not the current value Va is smaller than the threshold value TA3 (step S17). If the current value Va is equal to or greater than the threshold value TA3, it is determined that the deformation state of the cleaning brush 43 is the second stage (step S18). If the current value Va is smaller than the threshold value TA3, it is determined that the deformation state of the cleaning brush 43 is the third stage (step S19). When the deformation state of the cleaning brush 43 is specified as described above, the process proceeds to the flowchart of FIG.

  And the ADF control part 11 judges whether the cleaning brush 43 is deform | transforming based on the detection result of the deformation | transformation state of the cleaning brush 43 (step S20). Here, if the cleaning brush 43 is in the initial state where it is not deformed, it is not necessary to perform the subsequent processing, and the processing ends. In contrast, if the cleaning brush 43 is deformed, the process proceeds to step S21 and subsequent steps in order to set the correction operation so that the correction operation corresponding to the deformation stage is executed after the cleaning operation is completed.

  The ADF control unit 11 determines whether or not the deformation state of the cleaning brush 43 is the first stage (step S21). If the first stage is the first correction operation (see FIG. 10), the reverse operation of the cleaning member 41 is set (step S22). Here, the number of rotations of the cleaning member 41 in the reverse direction is set as N1. When the setting is finished, this process is finished.

  On the other hand, when the deformation state of the cleaning brush 43 is not in the first stage, the ADF control unit 11 next determines whether or not the deformation state of the cleaning brush 43 is in the second stage (step S23). If it is a stage, in order to perform the 1st correction operation (refer to Drawing 10) mentioned above after the end of cleaning operation, reverse operation of cleaning member 41 is set up (Step S24). Here, the number of times that the cleaning member 41 is rotated in the reverse direction is set as N2 times that is larger than that in the first stage. When the setting is finished, this process is finished.

  When the deformation state of the cleaning brush 43 is not in the second stage (that is, in the third stage), the ADF control unit 11 performs the above-described second correction operation (see FIG. 11) after the cleaning operation is completed. In order to execute, a brazing operation for correcting the deformation of the cleaning brush 43 is set (step S25). At this time, the brazing state may be set to be maintained for a predetermined time after the cleaning operation is completed, or the home position of the cleaning member 41 may be changed to the brazing state. When the setting is finished, this process is finished.

  By such processing, the ADF control unit 11 can detect the deformation state of the cleaning brush 43 during the braking operation by the cleaning brush 43, and when the cleaning brush 43 is detected to be in the deformation state, the cleaning operation ends. It is set to perform the first or second correction operation later according to the stage of the deformation state. Therefore, since the first or second correction operation is performed after the cleaning operation is completed, the cleaning brush 43 is corrected so that the shape of the brush returns to the initial state without deteriorating its deformation state. become.

  As described above, the present embodiment is configured to detect the drive current when the motor M1 operates the cleaning brush 43 as information that changes with the deformation of the cleaning brush 43, and the rotational position of the cleaning brush 43 is predetermined. The deformation state of the cleaning brush 43 is specified based on the drive current when the position is detected. Therefore, the deformation state of the cleaning brush 43 can be accurately detected. Further, when the cleaning brush 43 is deformed, the deformation of the cleaning brush 43 can be corrected by performing the above-described first or second correction operation, so that the cleaning performance can be improved. is there.

(Second Embodiment)
Next, a second embodiment will be described. In this embodiment, when the cleaning brush 43 is in contact with the foreign material cleaning member 50 and the foreign material cleaning member 50 is scraping off the foreign material attached to the cleaning brush 43 as information that changes as the cleaning brush 43 is deformed. A mode in which vibrations of the above are detected will be described. In the present embodiment, the overall configurations of the image processing apparatus 1 and the image reading apparatus 4 are the same as those shown in FIGS.

  FIG. 14 is an enlarged view showing a configuration of a portion where the glass surface cleaning mechanism 40 is provided in the present embodiment. In the present embodiment, the vibration detection sensor 51 is attached to the upper surface of the foreign material cleaning member 50 for scraping the foreign material attached to the cleaning brush 43. The vibration detection sensor 51 can detect at least vibrations in the vertical direction. The cleaning brush 43 contacts the foreign matter cleaning member 50, and the foreign matter cleaning member 50 scrapes off the foreign matter attached to the cleaning brush 43. It is configured to detect the vertical vibration generated in the foreign material scraping member 50 in the state in which it is present.

  FIG. 15 is a block diagram showing a control mechanism for controlling the image reading apparatus 4 in the present embodiment. This control mechanism is different from the first embodiment in that a current detection circuit for detecting the drive current of the motor M1 is not necessary, and instead, the signal detected and output by the vibration detection sensor 51 described above is not necessary. The point is that it is configured to be input to the ADF control unit 11. The ADF control unit 11 is configured to detect the deformation state of the cleaning brush 43 based on the vibration output input from the vibration detection sensor 51.

  More specifically, when the cleaning brush 43 is in an initial state in which the cleaning brush 43 is not deformed, when the foreign matter cleaning member 50 performs the cleaning operation of the foreign matter, the portion close to the root of the cleaning brush 43 is the foreign matter cleaning member 50. Since it contacts, the impact at the time of the contact will become large and the vibration width which the cleaning brush 41 gives to the foreign material scraping member 50 will also become large. On the other hand, when the cleaning brush 43 is gradually deformed, the contact portion with the foreign material scraping member 50 is changed to the tip side of the cleaning brush 43, so that the impact at the time of contact is reduced, and the cleaning brush 41 becomes foreign matter. The vibration width given to the scraping member 50 is also gradually reduced. Therefore, it is possible to detect the deformation state of the cleaning brush 43 by detecting the vibration width of the foreign material scraping member 50.

  FIG. 16 is a diagram illustrating an example of a change characteristic of the vibration output by the vibration detection sensor 51 when the cleaning brush 43 and the foreign material scraping member 50 come into contact with each other. The vibration output Lb shown in FIG. 16 indicates that when the cleaning brush 43 contacts the foreign material cleaning member 50, the foreign material cleaning member 50 vibrates greatly due to the impact. At this time, the vibration width H is maximized. After that, the vibration is gradually attenuated, and the vibration is eventually stopped. Here, the magnitude of the vibration width H of the vibration output Lb corresponds to the change state of the cleaning brush 43.

  FIG. 17 is a diagram illustrating the vibration output of the foreign material scraping member 50 that changes according to the deformation state of the cleaning brush 43. In the drawing, a vibration output Lb1 indicates a vibration output when the cleaning brush 43 and the foreign material scraping member 50 are in contact with each other in an initial state where the cleaning brush 43 is not deformed. In this state, the impact when the cleaning brush 43 and the foreign material scraping member 50 come into contact with each other is large, and the vibration width H is also large. When the cleaning brush 43 is gradually deformed by repeating the cleaning operation, the vibration output from the vibration detection sensor 51 gradually decreases from Lb1 to Lb2, Lb3, and Lb4.

  In the present embodiment, as shown in FIG. 17, the position detection sensor 45 is configured to be turned on at the timing Ts when the cleaning brush 43 and the foreign material scraping member 50 come into contact with each other. The vibration output output by the vibration detection sensor 51 is read at the timing Ts when the detection sensor 45 is turned on, and the maximum vibration width H is measured from the vibration output. For example, the vibration output is sampled for a certain period T from the timing Ts when the position detection sensor 45 is turned on, and the vibration width H that is maximum within the period T is detected. Then, the ADF control unit 11 determines the deformation state of the cleaning brush 43 based on the maximum vibration width H.

  A plurality of threshold values H1, H2, and H3 (however, H1> H2> H3) for determining the deformation stage of the cleaning brush 43 are stored in advance in the memory 11b of the ADF control unit 11, and the ADF control unit 11 has a foreign object. The deformation state of the cleaning brush 43 is determined by comparing the maximum vibration width H of the scraping member 50 with the threshold values H1, H2, and H3. For example, as shown in FIG. 17, if sampling is performed in response to the timing Ts when the position detection sensor 45 is turned on and the detected maximum vibration width H corresponds to the vibration output Lb1, the maximum vibration width H is Since it is larger than the threshold value H1, it is determined that the cleaning brush 43 is in an initial state that is not deformed. If the detected maximum vibration width H corresponds to the vibration output Lb2, since the maximum vibration width H is smaller than the threshold value H1 and larger than the threshold value H2, the cleaning brush 43 is deformed slightly from the initial state. It is determined that this is the first stage. If the detected maximum vibration width H corresponds to the vibration output Lb3, the maximum vibration width H is smaller than the threshold value H2 and larger than the threshold value H3, so that the cleaning brush 43 is further slightly deformed from the first stage. Judge that it is the second stage. Further, if the detected maximum vibration width H corresponds to the vibration output Lb4, since the maximum vibration width H is smaller than the threshold value H3, it is determined that the cleaning brush 43 is the third stage further deformed from the second stage. To do.

  Here, when the cleaning brush 43 is deformed, an example in which the deformed state is detected in three stages is shown, but this need not necessarily be in three stages, and may be in one stage. There may be two stages. Furthermore, it is good also as four steps or more.

  In this embodiment, as in the first embodiment, when the deformation state of the cleaning brush 43 is detected and it is determined that the cleaning brush 43 is in a deformed state from the initial state, the ADF control unit 11 However, the glass surface cleaning mechanism 40 is controlled according to the stage of the deformation state, and a correction operation for correcting the deformation of the cleaning brush 43 is performed. The details of the correction operation are the same as those described in the first embodiment.

  Next, a processing sequence for detecting and correcting the deformation state of the cleaning brush 43 in the present embodiment will be described. FIG. 18 is a flowchart showing the processing procedure of the first half of a series of processing procedures by the ADF control unit 11. The latter half of the processing procedure following this processing procedure is the same as the flowchart of FIG. 13 described in the first embodiment.

  The process shown in FIG. 18 is a process that is repeatedly executed every predetermined time (for example, several milliseconds) by the ADF control unit 11 when, for example, the conveyance operation of the document 9 is started in the automatic document conveyance device 3. It is a process that is repeatedly executed in the middle. As illustrated in FIG. 18, the ADF control unit 11 first determines whether or not the cleaning member 41 is rotating (step S30). Here, when the cleaning member 41 is not operating (in the case of NO), since the cleaning operation is not being performed, this process is terminated. On the other hand, when the cleaning member 41 is operating (in the case of YES), the process proceeds to step S31.

  When the cleaning member 41 is performing the cleaning operation, the ADF control unit 11 determines whether or not the position detection sensor 45 is turned on (step S31). Here, if the position detection sensor 45 is off, the cleaning member 41 has not yet reached the rotational position where the deformation state of the cleaning brush 43 can be confirmed. . On the other hand, if the position detection sensor 45 is on, the cleaning member 41 has reached the rotational position where the deformation state of the cleaning brush 43 can be confirmed, so that the determination becomes YES, and the process proceeds to step S32.

  When the position detection sensor 45 is on, the ADF control unit 11 samples the vibration output output from the vibration detection sensor 51 for a certain period, and measures the maximum vibration width H (step S32). Then, the ADF control unit 11 compares the measured maximum vibration width H with the threshold value H1, and determines whether or not the maximum vibration width H is smaller than the threshold value H1 (step S33). If the maximum vibration width H is equal to or greater than the threshold value H1, the determination is NO and the process proceeds to step S34, where it is determined that the cleaning brush 43 is in an initial state that is not deformed. On the other hand, when the maximum vibration width H is smaller than the threshold value H1, the cleaning brush 43 is determined to be deformed.

  Then, the ADF control unit 11 determines whether or not the maximum vibration width H is smaller than the threshold value H2 in order to specify the stage of the deformation state (step S35). If the maximum vibration width H is greater than or equal to the threshold value H2, it is determined that the deformation state of the cleaning brush 43 is the first stage (step S36). On the other hand, if the maximum vibration width H is smaller than the threshold value H2, it is further determined whether or not the maximum vibration width H is smaller than the threshold value H3 (step S37). If the maximum vibration width H is greater than or equal to the threshold value H3, it is determined that the deformation state of the cleaning brush 43 is the second stage (step S38). If the maximum vibration width H is smaller than the threshold value H3, it is determined that the deformation state of the cleaning brush 43 is the third stage (step S39). When the deformation state of the cleaning brush 43 is specified as described above, the process thereafter proceeds to the flowchart of FIG. 13. When the cleaning brush 43 is deformed as described above, correction according to the stage of the deformation state is performed. The action is set and the process ends.

  As described above, the present embodiment is configured to detect the vibration width when the foreign material scraping member 50 scrapes the foreign matter attached to the cleaning brush 43 as information that changes as the cleaning brush 43 is deformed. The deformation state of the cleaning brush 43 is specified based on the vibration width of the foreign material scraping member 50 when it is detected that the rotational position of the brush 43 is a predetermined position. Therefore, the deformation state of the cleaning brush 43 can be accurately detected. Further, when the cleaning brush 43 is deformed, the deformation of the cleaning brush 43 can be corrected by performing the above-described first or second correction operation, so that the cleaning performance can be improved. is there.

  When the automatic document feeder 3 transports a document, vibration associated with the document transport operation is generated, and the vibration detection sensor 51 detects the vibration. Therefore, in this embodiment described above, vibration detection is performed in response to the detection of the rotation of the cleaning member 41 to the predetermined position by the position detection sensor 45 in order to avoid erroneous detection of vibration due to the document conveying operation. The vibration output of the sensor 51 is sampled. However, when the vibration caused by the document conveying operation in the automatic document conveying device 3 is smaller than the vibration given to the foreign material cleaning member 50 by the cleaning brush 43 coming into contact with the foreign material cleaning member 50, the vibration is always generated. You may comprise so that the vibration output of the detection sensor 51 may be sampled.

(Third embodiment)
Next, a third embodiment will be described. In the present embodiment, as information that changes with the deformation of the cleaning brush 43, when the cleaning brush 43 is rotated in the rotation direction R1 while the cleaning brush 43 is not deformed, the cleaning brush 43 and the reading glass 21 are changed. A description will be given of an embodiment in which image reading is performed at the contact start position where contact is first made and the density level of the read image is detected. In this embodiment, the overall configuration of the image processing apparatus 1 is the same as that shown in FIG.

  FIG. 19 is a schematic diagram showing an overall internal configuration of the image reading apparatus 4 in the present embodiment. In the present embodiment, a motor M2 is provided inside the scanner unit 2, and this motor M2 moves a reading head 29, which includes an exposure device 22 and a plurality of mirrors 23, into a unit in the direction of arrow S in the figure. Move. Therefore, the reading position 20 by the scanner unit 2 moves in the direction of arrow S in the figure as the motor M2 moves the reading head 29.

  FIG. 20 is an enlarged view showing a configuration of a portion where the glass surface cleaning mechanism 40 is provided in the present embodiment. A reading position 20a shown in FIG. 20 is a reading position when the scanner unit 2 reads a document, and a reading position 20b is a reading position for reading an image at the tip of the cleaning brush 43 and measuring its density level. . The reading position 20b is substantially the same position as the contact start position where the tip of the cleaning brush 43 first contacts the reading glass 21 when the cleaning brush 43 is rotated in the rotation direction R1 in an initial state where the cleaning brush 43 is not deformed. It is. The motor M2 can move the reading position 20 of the scanner unit 2 between the reading positions 20a and 20b by moving the reading head 29 in the S direction.

  FIG. 21 is a block diagram showing a control mechanism for controlling the image reading apparatus 4 in the present embodiment. In this control mechanism, the scanner control unit 12 in the scanner unit 2 is configured to control the motor drive unit 28 that drives the motor M2. The scanner control unit 12 performs data communication with the ADF control unit 11, and when the concentration measurement is instructed from the ADF control unit 11, the scanner control unit 12 outputs a pulse signal to the motor driving unit 28 to drive the motor M2, thereby reading the reading position. 20 is moved from the reading position 20a of the original to the reading position 20b of the front end image of the cleaning brush 43. In this state, the exposure device 22, the image reading unit 25, and the image processing unit 26 are operated to perform image reading, and the density level of the read image is output to the ADF control unit 11. Thereafter, the scanner control unit 12 drives the motor M2 again to move the reading position 20 from the reading position 20b to the reading position 20a of the original so that the original image can be read.

  The ADF control unit 11 according to the present embodiment is configured to detect the deformation state of the cleaning brush 43 based on the density level acquired from the scanner control unit 12.

  FIG. 22 is a diagram illustrating changes in the density level depending on the deformation state of the cleaning brush 43. First, as shown in FIG. 22A, when the scanner unit 2 reads the tip image of the cleaning brush 43 at the reading position 20b, the brush tip 43a is positioned at the reading position 20b in the initial state where the cleaning brush 43 is not deformed. Since the upper reading glass 21 is almost touched, the density level of the read image is increased. On the other hand, when the cleaning brush 43 is deformed, the brush tip 43b is separated from the reading glass 21 above the reading position 20b, so that the density level of the read image is lowered. That is, as shown in FIG. 22A, when the tip image of the cleaning brush 43 is read at the reading position 20b, the density level Lc of the read image is shown in FIG. 22B according to the deformation state of the cleaning brush 43. The level will be as shown. In FIG. 22B, the density level Lc1 indicates the density level when the tip image of the cleaning brush 43 is read in the initial state where the cleaning brush 43 is not deformed, and is the highest level. When the cleaning brush 43 is gradually deformed by repeating the cleaning operation, the concentration level Lc gradually decreases from Lc1 to Lc2, Lc3, and Lc4. Therefore, it is possible to detect the deformation state of the cleaning brush 43 by measuring this density level.

  In this embodiment, the position detection sensor 45 is configured to be turned on at the timing Ts when the cleaning brush 43 is rotated to the contact start position described above, and the ADF control unit 11 is configured to be the timing at which the position detection sensor 45 is turned on. At Ts, the scanner controller 12 is instructed to measure density. At this time, when the scanner unit 2 cannot immediately read the image at the reading position 20b, it is preferable that the ADF control unit 11 temporarily stops the rotation of the cleaning brush 43. In this case, when the ADF control unit 11 acquires the density level from the scanner control unit 12, the rotational driving of the cleaning brush 43 is resumed.

  When the ADF control unit 11 instructs the scanner control unit 12 to measure density, and acquires the density level Lc measured by the scanner control unit 12, the ADF control unit 11 determines the deformation state of the cleaning brush 43 based on the density level Lc. . In the memory 11b of the ADF control unit 11, a plurality of threshold values Tc1, Tc2, Tc3 (where Tc1> Tc2> Tc3) for determining the deformation stage of the cleaning brush 43 are stored in advance as shown in FIG. The ADF control unit 11 determines the deformation state of the cleaning brush 43 by comparing the density level Lc of the tip image of the cleaning brush 43 with the threshold values Tc1, Tc2, and Tc3. For example, when the density level Lc is Lc1, since it is larger than the threshold value Tc1, it is determined that the cleaning brush 43 is in an initial state that is not deformed. When the density level Lc is Lc2, the cleaning brush 43 is determined to be in the first stage of the deformed state slightly deformed from the initial state because it is smaller than the threshold Tc1 and larger than the threshold Tc2. When the density level Lc is Lc3, it is determined that the cleaning brush 43 is in the second stage which is further modified from the first stage because it is smaller than the threshold value Tc2 and larger than the threshold value Tc3. Further, when the density level Lc is Lc4, it is determined that the cleaning brush 43 is in the third stage further deformed from the second stage because it is smaller than the threshold value Tc3.

  Here, when the cleaning brush 43 is deformed, an example in which the deformed state is detected in three stages is shown, but this need not necessarily be in three stages, and may be in one stage. There may be two stages. Furthermore, it is good also as four steps or more.

  Also in the present embodiment, as in the first embodiment, when the deformation state of the cleaning brush 43 is detected and it is determined that the cleaning brush 43 is deformed from the initial state, the ADF control unit 11 However, the glass surface cleaning mechanism 40 is controlled according to the stage of the deformation state, and a correction operation for correcting the deformation of the cleaning brush 43 is performed. The details of the correction operation are the same as those described in the first embodiment.

  Next, a processing sequence for detecting and correcting the deformation state of the cleaning brush 43 in the present embodiment will be described. 23 and 24 are flowcharts showing the processing procedure of the first half of a series of processing procedures by the ADF control unit 11. The latter half of the processing procedure following this processing procedure is the same as the flowchart of FIG. 13 described in the first embodiment.

  The process shown in FIG. 23 is a process that is repeatedly executed by the ADF control unit 11 every predetermined time (for example, several milliseconds) when the operation of transporting the document 9 is started in the automatic document transport device 3, for example. It is a process that is repeatedly executed in the middle. As shown in FIG. 23, the ADF control unit 11 first determines whether or not the cleaning member 41 is rotating (step S40). Here, when the cleaning member 41 is not operating (in the case of NO), since the cleaning operation is not being performed, this process is terminated. On the other hand, when the cleaning member 41 is operating (in the case of YES), the process proceeds to step S41.

  When the cleaning member 41 is performing the cleaning operation, the ADF control unit 11 determines whether or not the position detection sensor 45 is turned on (step S41). Here, if the position detection sensor 45 is off, the cleaning member 41 has not yet reached the rotational position where the deformation state of the cleaning brush 43 can be confirmed. . On the other hand, if the position detection sensor 45 is on, the cleaning member 41 has reached the rotational position where the deformation state of the cleaning brush 43 can be confirmed, so that the determination becomes YES and the process proceeds to step S42.

  In step S42, a cleaning brush state measurement process is performed. Details of this processing are shown in FIG. The ADF control unit 11 temporarily stops the rotation operation of the cleaning member 41 (step S421), and transmits a density measurement instruction to the scanner control unit 12 (step S422). Thus, the scanner unit 2 performs a process of moving the reading position 20 from the reading position 20a of the document to the reading position 20b of the front end image of the cleaning brush 43, and reads the front end image of the cleaning brush 43 at the reading position 20b. Processing is performed. Then, the density level Lc of the read image is measured and output to the ADF control unit 11. When the ADF control unit 11 obtains the density level Lc of the cleaning brush 43 from the scanner control unit 12 (step S423), the driving of the cleaning member 41 that has been temporarily stopped is resumed (step S424). Thus, the cleaning brush state measurement process in step S42 is completed, and the process returns to the flowchart in FIG.

  Then, the ADF control unit 11 compares the density level Lc acquired from the scanner control unit 12 with the threshold value Tc1, and determines whether or not the density level Lc is smaller than the threshold value Tc1 (step S43). If the density level Lc is greater than or equal to the threshold value Tc1, the determination is NO and the process proceeds to step S44, where it is determined that the cleaning brush 43 is in an initial state that is not deformed. On the other hand, when the density level Lc is smaller than the threshold value Tc1, it is determined that the cleaning brush 43 is deformed.

  Then, the ADF control unit 11 determines whether or not the density level Lc is smaller than the threshold value Tc2 in order to specify the stage of the deformation state (step S45). If the density level Lc is greater than or equal to the threshold value Tc2, it is determined that the deformation state of the cleaning brush 43 is the first stage (step S46). On the other hand, when the density level Lc is smaller than the threshold value Tc2, it is further determined whether or not the density level Lc is smaller than the threshold value Tc3 (step S47). If the density level Lc is equal to or greater than the threshold value Tc3, it is determined that the deformation state of the cleaning brush 43 is the second stage (step S48). If the density level Lc is smaller than the threshold value Tc3, it is determined that the deformed state of the cleaning brush 43 is the third stage (step S49). When the deformation state of the cleaning brush 43 is specified as described above, the process thereafter proceeds to the flowchart of FIG. 13. When the cleaning brush 43 is deformed as described above, correction according to the stage of the deformation state is performed. The action is set and the process ends.

  As described above, the present embodiment is configured to detect the density level Lc of the tip image of the cleaning brush 43 as information that changes with the deformation of the cleaning brush 43, and the rotational position of the cleaning brush 43 is a predetermined position. The image is sometimes read, and the deformation state of the cleaning brush 43 is specified based on the density level Lc of the read image. Therefore, the deformation state of the cleaning brush 43 can be accurately detected. Further, when the cleaning brush 43 is deformed, the deformation of the cleaning brush 43 can be corrected by performing the above-described first or second correction operation, so that the cleaning performance can be improved. is there.

  In the above description, the case where the rotation of the cleaning member 41 is temporarily stopped after the position detection sensor 45 is turned on is illustrated. However, the movement of the reading position 20 is performed in advance before the position detection sensor 45 is turned on. In this case, it is not necessary to temporarily stop the rotation of the cleaning member 41, so that a smooth cleaning operation is possible, which is more preferable.

  Further, in the above, the image reading unit of the scanner unit 2 measures the density level by moving the reading position 20 where the scanner unit 2 reads an image from the reading position 20a of the document to the reading position 20b where the front end image of the cleaning brush 43 is read. Although the embodiment used as the means has been described, a configuration in which a dedicated density level measuring means for reading the front end image of the cleaning brush 43 and measuring the density level is provided separately from the image reading means for reading the image of the document.

(Modification)
As mentioned above, although several embodiment regarding this invention was described, this invention is not limited to the thing of the content mentioned above. For example, in the above-described embodiment, the case where the image processing apparatus 1 is an apparatus having a plurality of functions such as a copy function, a FAX function, a printer function, and a scanner function has been illustrated. There is no need to be. In particular, the image reading apparatus 4 described above can be applied to an apparatus having at least one of a copy function, a FAX function, and a scanner function.

  In each of the above-described embodiments, the configuration example in which the position detection sensor 45 is provided as the position detection unit that detects the rotational position of the cleaning brush 43 has been described. However, the position detection unit does not necessarily have to be the position detection sensor 45. For example, the position detection means for detecting the rotational position of the cleaning brush 43 is configured by counting the driving time after starting the motor M1 or counting the number of pulses sent to drive the motor M1. You may do it.

  In addition, it goes without saying that various modifications can be applied to the above-described embodiments within the scope of the present invention.

It is a perspective view which shows an example of the external appearance structure of the image processing apparatus provided with the image reading function. 1 is a schematic diagram illustrating an overall internal configuration of an image reading apparatus. It is an enlarged view which shows the structure of the part in which the glass surface cleaning mechanism was provided in 1st Embodiment. It is a figure which shows the flow of the cleaning operation by a cleaning brush. It is a figure which shows the flow of the cleaning operation by a cleaning brush. It is a figure which shows the flow of the cleaning operation by a cleaning brush. FIG. 3 is a block diagram illustrating a control mechanism for controlling the image reading apparatus according to the first embodiment. It is a figure which shows the change characteristic of the drive current of the motor during the cleaning operation by a cleaning brush. It is a figure which shows the drive current of the motor which changes according to the deformation | transformation state of a cleaning brush. It is a figure which shows 1st correction | amendment operation | movement when the cleaning brush has deform | transformed. It is a figure which shows 2nd correction | amendment operation | movement when the cleaning brush has deform | transformed. It is a flowchart which shows the process procedure of the first half of a series of process procedures by an ADF control part. It is a flowchart which shows the process procedure of the latter half of a series of process procedures by an ADF control part. It is an enlarged view which shows the structure of the part in which the glass surface cleaning mechanism was provided in 2nd Embodiment. It is a block diagram which shows the control mechanism for controlling the image reading apparatus in 2nd Embodiment. It is a figure which shows an example of the change characteristic of the vibration output by a vibration detection sensor when a cleaning brush and a foreign material scraping member contact. It is a figure which shows the vibration output of the foreign material scraping member which changes according to the deformation | transformation state of a cleaning brush. It is a flowchart which shows the process procedure of the first half part of a series of process procedures by an ADF control part. It is the schematic which shows the whole internal structure of the image reading apparatus in 3rd Embodiment. It is an enlarged view which shows the structure of the part in which the glass surface cleaning mechanism was provided in 3rd Embodiment. It is a block diagram which shows the control mechanism for controlling the image reading apparatus in 3rd Embodiment. It is a figure which shows the change of the density level by the deformation | transformation state of a cleaning brush. It is a flowchart which shows the process procedure of the first half part of a series of process procedures by an ADF control part. It is a flowchart which shows an example of the detailed process sequence of a cleaning brush state measurement process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image processing apparatus 2 Scanner part 3 Automatic document feeder (ADF)
4 Image Reading Device 11 ADF Control Unit (Control Unit)
20 reading position 20a reading position 20b reading position 21 reading glass 25 image reading unit (image reading means, density level measuring means)
29 Reading head 40 Glass surface cleaning mechanism (glass surface cleaning means)
41 Cleaning member 43 Cleaning brush 45 Position detection sensor (position detection means)
48 Current detection circuit (Current detection means)
50 Foreign matter cleaning member (foreign matter cleaning means)
51 Vibration detection sensor (vibration detection means)
M1 motor (drive means)
M2 motor (moving means)
G Foreign matter

Claims (11)

An image reading apparatus that conveys documents one by one on a reading glass surface and performs image reading when the document passes a reading position on the reading glass surface,
A cleaning brush that is disposed to face the reading glass across the document conveyance path and that contacts the reading glass by operating in a predetermined rotation direction and cleans the surface of the reading glass;
Control means for controlling the cleaning operation of the cleaning brush;
Position detecting means for detecting the rotational position of the cleaning brush;
With
The image reading apparatus according to claim 1, wherein the control unit detects a deformation state of the cleaning brush caused by repeating a cleaning operation.   In response to detecting that the rotational position of the cleaning brush is a predetermined position by the position detecting means, the control means acquires information that changes with deformation of the cleaning brush, and The image reading apparatus according to claim 1, wherein a deformation state of the cleaning brush is detected based on the image reading apparatus.   The image reading apparatus according to claim 1, wherein the control unit causes the cleaning brush to be deformed during a cleaning operation of the cleaning brush. Drive means for driving the cleaning brush in the rotational direction;
Current detecting means for detecting a driving current when the driving means drives the cleaning brush;
Further comprising
The control means is responsive to the position detection means detecting that the rotational position of the cleaning brush is a predetermined position, based on the drive current of the drive means detected by the current detection means. The image reading apparatus according to claim 1, wherein a deformation state of the brush is detected.   The image reading apparatus according to claim 4, wherein the predetermined position is a position where the cleaning brush contacts the reading glass. Provided further on the downstream side of the rotation direction of the cleaning brush, further comprising a foreign matter scraping means for scraping the foreign matter adhering to the cleaning brush during the cleaning operation from the cleaning brush,
The image reading apparatus according to claim 4, wherein the predetermined position is a position where the cleaning brush and the foreign matter cleaning unit are in contact with each other. Foreign matter scraping means provided on the downstream side of the rotational direction of the cleaning brush and scraping foreign matter adhering to the cleaning brush during the cleaning operation from the cleaning brush;
Vibration detecting means for detecting vibration when the foreign matter scraping means comes into contact with the cleaning brush and scrapes foreign matter from the cleaning brush;
Further comprising
In response to detecting that the rotational position of the cleaning brush is in contact with the cleaning brush by the position detecting means, the control means is configured to detect the foreign matter scraping means detected by the vibration detecting means. The image reading apparatus according to claim 1, wherein a deformation state of the cleaning brush is detected based on a vibration width. When the cleaning brush is rotated in the rotation direction with the cleaning brush not deformed, image reading is performed at a contact start position where the cleaning brush and the reading glass first contact each other, and the density of the read image A concentration level measuring means for detecting the level;
In response to detecting that the rotational position of the cleaning brush is the contact start position by the position detecting means, the control means is configured to detect the cleaning brush based on the density level detected by the density level measuring means. The image reading apparatus according to claim 1, wherein a deformation state of the image reading apparatus is detected. An image reading unit having a reading head provided corresponding to the reading position and configured to read an image at the reading position via the reading head;
Moving means for moving the read head;
With
9. The moving unit according to claim 8, wherein the moving unit moves the reading head to move the reading position to the contact start position, so that the image reading unit can be used as the density level measuring unit. Image reading device.   The image reading apparatus according to claim 1, wherein when the cleaning brush is deformed, the control unit rotates the cleaning brush a predetermined number of times in a direction opposite to the rotation direction. .   The said control means stops the said cleaning member as the state which pressed down the deformation | transformation direction side with the predetermined | prescribed member, when the said cleaning brush is deform | transforming. Image reading apparatus.

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