JP5642829B2 - Image reading device - Google Patents

Description

  The present invention relates to an image reading apparatus such as a scanner that transports a document using a transport mechanism and reads an image of the document.

  An example of this type of conventional image reading apparatus is shown in FIG.

  The image reading apparatus includes a lower unit 1 and an upper unit 2 supported so as to be rotatable in the vertical direction with respect to the lower unit 1 via a hinge 13. The document transport unit is opened and closed by the rotation of the upper unit 2. The open / closed state of the document transport unit is detected by the open / close detection sensor 37, and the transport path is formed when the document transport unit is closed so that the document can be transported.

  Then, the image reading apparatus starts an image reading operation based on an operation unit (not shown) or a control signal from the outside. First, the uppermost document 8 on the document stack loaded on the document table 7 is raised until it comes into contact with the pickup roller 6 serving as a paper feeding means. The document 8 is fed to the conveyance path by the roller 6 and the feeding roller 4 as feeding means.

  When two or more documents 8 are picked up (feeded) at one time by the pickup roller 6, the documents are separated by the separation roller 11 and fed one by one to the conveyance path. The document 8 fed to the conveyance path and separated and fed is read by the reading sensor 12 on the conveyance path, and the image data is transferred to an image processing unit (not shown). The registration sensor 14 detects the leading and trailing ends of the document 8 conveyed on the conveyance path, and the conveyance timing and the like are controlled using the signal of the registration sensor 14.

  A platen roller 10 is disposed at a position facing the reading sensor 12 across the conveyance path of the document 8. The platen roller 10 is used as a background member that changes the background color of the read image of the document 8 by the reading sensor 12, and a predetermined gap is provided between the platen roller 10 and the reading sensor 12.

  That is, in the platen roller 10, for example, the half-circumferential region of the outer peripheral surface is a black portion, and the remaining half-circular region is a white portion. By controlling the rotation operation of the platen roller 10, the background color of the document can be switched by arranging the black portion or the white portion at a position facing the reading sensor 12.

  In this case, switching the background color of the document to black makes it easy to emphasize the outline of the document, recognize the outline of the read document, and create image data that matches the outline. In addition, in a double-sided printing original that is easy to see through, the background color should be black because the original is transparent and printing on the back side is emphasized. On the other hand, for a document having a low density of printing or printing and having no printing or printing on the back side, the background color can be white to emphasize printing or printing.

  The platen roller 10 is driven by a driving motor 15 such as a stepping motor, and rotates when the background color of the document is switched and when the reading surface of the reading sensor 12 is cleaned. At the time of document reading, the platen roller 10 is controlled to stop at a constant holding torque applied by the drive motor 15.

  The document 8 that has passed through the reading sensor 12 is conveyed downstream by the conveying roller 3, and is then discharged to the discharge tray 9 by the discharge roller 5. A series of these document conveying operations is performed until timing is controlled so as to ensure a predetermined document interval, and all the documents 8 stacked on the document table 7 are conveyed. After all the documents 8 loaded on the document table 7 are transported, the document table 7 descends and returns to the home position.

  The platen roller 10 is provided with a cleaning member 16 that cleans the reading surface of the reading sensor 12. When the platen roller 10 is rotated at a predetermined timing after the document is conveyed and the image of the document is read, the cleaning member 16 passes while contacting the reading surface of the reading sensor 12 to clean the reading surface. (Patent Document 1).

  When reading a document continuously, the registration sensor 14 detects the interval between the documents, that is, the trailing edge of the document 8 to be conveyed, and uses a signal of the registration sensor 14 to detect a certain time later. Then, cleaning of the reading surface of the reading sensor 12 by the cleaning member 16 and rotation operation of the platen roller 10 for setting the set background color are performed.

Japanese Patent No. 3645737

  However, in the conventional image reading apparatus, the registration sensor 14 detects the rear end of the document 8 near the center in the main scanning direction. Therefore, when the document 8 is skewed, the vicinity of the center of the rear end of the document 8 is the reading sensor 12. , But the corner of the rear end of the document 8 may not have passed the reading sensor 12 in some cases. In this case, if the reading surface of the reading sensor 12 is cleaned by the cleaning member 16 by rotating the platen roller 10 at the same timing as when the document 8 is not skewed, the conveyance of the document 8 is hindered. It may cause damage or paper jam.

  On the other hand, after the registration sensor 14 detects the trailing edge of the document 8, the platen roller 10 is rotated at a timing with sufficient time so that the skewed document 8 reliably passes the reading sensor 12. It is conceivable to clean the reading surface of the reading sensor 12 with the cleaning member 16.

Accordingly, an object of the present invention to provide an image reading apparatus capable of being continuously conveying a plurality of document stably, to clean the sensor reading with a cleaning member mounted to the rotary member.

To achieve the above object, an image reading apparatus of the present invention, the sensor reading to read an image of the originals to be conveyed (12), a rotary member (25) that are opposite to the reading sensor, said rotating A rotation drive means (15) for rotating the member; one end side of the rotation member is fixed to the rotation member, and the other end side protrudes from an outer peripheral portion of the rotation member, and contacts the reading sensor when the rotation member rotates. comprising cleaning and member (16) to clean the surface of the reading sensor, the outer peripheral portion of the rotary member is provided with a groove, the rotary member is rotated and the cleaning member is in contact with the reading sensor In this case, the cleaning member is housed in the groove .

According to the present invention, while continuously conveying a plurality of document stably, the sensor reading with a cleaning member mounted to the rotary member can be cleaned.

1 is a schematic sectional view for explaining an image reading apparatus according to a first embodiment of the present invention. It is a perspective view for demonstrating a platen roller unit. It is a disassembled perspective view for demonstrating a platen roller. It is a figure for demonstrating the example of attachment of a platen roller unit. It is a figure for demonstrating the example of attachment of a platen roller unit. It is a figure for demonstrating the example of attachment of a platen roller unit. It is a figure for demonstrating the connection example of a main body apparatus and a platen roller unit. FIG. 6 is an explanatory diagram for explaining an example of calculating a skew amount of a trailing edge of a document by a control circuit. It is a schematic block diagram for demonstrating the control system of an image reading apparatus. It is a figure for demonstrating the image reading apparatus which is the 3rd Embodiment of this invention. It is a figure for demonstrating the image reading apparatus which is the 4th Embodiment of this invention. It is a simplified cross-sectional view for explaining a conventional image reading apparatus.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view for explaining an image reading apparatus according to a first embodiment of the present invention. The basic structure of the image reading apparatus according to the present embodiment is substantially the same as that of the conventional image reading apparatus already described with reference to FIG. The same reference numerals are given to the descriptions, and the description thereof is omitted or simplified.

  In the image reading apparatus according to the first embodiment of the present invention, as shown in FIG. 1, skew detection sensors 40 and 41 are arranged on the upstream side of the registration sensor 14, and instead of the conventional platen roller 10. The platen roller 25 is used.

The platen roller 25 will be described with reference to FIG. 3. The platen roller (rotating member) 25 cleans the semicylindrical black member 26, the semicylindrical white member 27, and the reading surface of the reading sensor 12. And a cleaning member 16. The cleaning member 16 has one end fixed to the platen roller 25 and the other end protruding from the outer periphery of the platen roller 25 (FIG. 1).

  For example, cylindrical fitting portions 26a and 26e and fitting portions 26c that protrude in the same axial direction are provided coaxially at both the axial end portions and the axial central portion of the black member 26, respectively. Further, a semi-disc-shaped light shielding portion 26 f for detecting the rotational position of the platen roller 25 is provided in the vicinity of the fitting portion 26 e of the black member 26. The shape and size of the light shielding part 26f are not particularly limited.

  The light shielding portion 26f shields the light receiving portion of the platen roller position detection sensor 35 (see FIG. 7) configured by a photo interrupter or the like by the rotation of the platen roller 25. The light shielding part 26f is formed of the same member as the black member 26. Thereby, it is not necessary to separately provide a member for shielding the light receiving part of the platen roller position detection sensor 35, the structure is simplified, and the cost can be reduced.

  In addition, when the light transmittance of the white member 27 is low, it is also possible to form the light shielding portion on the white member 27 with the same member.

  For example, cylindrical fitted portions 27a and 27e and fitted portions 27c in which the fitted portions 26a and 26e and the fitted portions 26c are fitted in the axial direction are provided at both axial ends and the central portion of the white member 27, respectively. It is provided on the same axis.

  In order to combine the black member 26 and the white member 27, first, the fitting portions 26a and 26e and the fitting portion 26c of the black member 26 are axially arranged with respect to the fitting portions 27a and 27e and the fitting portion 27c of the white member 27. The black member 26 and the white member 27 are aligned in the radial direction while being shifted to one end side (left end side in the figure). At this time, the cleaning member 16 is interposed between the joint portions on one side of the joint portions on both sides along the axial direction of the black member 26 and the white member 27.

  Next, the black member 26 is slid relative to the white member 27 toward the other end side in the axial direction (the right end side in the drawing), so that the fitting portions 26 a and 26 e and the fitting portion 26 c of the black member 26 become the white member 27. The fitting parts 27a and 27e and the fitting part 27c are fitted in the axial direction.

  Thus, the black member 26 and the white member 27 are combined, and the cleaning member 16 is attached in a state of protruding between the black member 26 and the white member 27. In addition, after combining in this way, the black member 26 and the white member 27 are prevented from coming off by a snap fit (not shown) or the like so as not to come off.

  Thereafter, the shaft 29 is inserted into the inner peripheral portions of the fitting portions 26a, 26c, and 26e of the black member 26, whereby the cylindrical platen roller 25 in which the shaft 29 protrudes at both ends in the axial direction is formed. In addition, the uneven | corrugated fitting structure of the black member 26 and the white member 27 is not specifically limited, A various uneven | corrugated fitting structure is employable.

  FIG. 2 is a perspective view of a platen roller unit (rotating member unit) 17 including a platen roller 25, holding members 21 and 22, and a conveyance guide 18.

  The holding members 21 and 22 hold a conveyance guide 18 that guides the document 8 being conveyed, and rotatably hold shafts 29 that protrude from both end portions in the axial direction of the platen roller 25 via bearings 19 and 20. doing.

After the platen roller unit 17 is mounted on the main body device, a predetermined gap is secured between the platen roller 25 and the reading sensor 12 by the reading sensor 12 coming into contact with the spacer portions 21 a and 22 a of the holding members 21 and 22. Is done.

  FIG. 4 is a diagram illustrating a state in which the platen roller unit 17 is attached to the main body device.

  In order to attach the platen roller unit 17 to the main unit, first, the upper unit 2 is opened with respect to the lower unit 1. On both side walls in the width direction perpendicular to the conveyance direction of the document 8 of the upper unit 2, as shown in FIG. 4, mounting portions 33 cut out in a substantially U shape are provided.

  Then, the platen roller unit 17 is disposed on the mounting portions 23 of the upper unit 2 with the bearing guides 19 and 20 in a state in which the conveyance guide 18 is disposed above and the axis of the platen roller 25 is disposed in the width direction of the upper unit 2. Insert.

  In this state, the platen roller unit 17 is attached to the upper unit 2 by rotating the platen roller unit 17 around the axis of the platen roller 25.

  Specifically, as shown in FIG. 4, a protrusion 34 is provided above the attachment portion 33 of the upper unit 2, and the bearing portions 19 and 20 provided on the holding members 21 and 22 of the platen roller unit 17 are provided on the bearing portions 19 and 20. , Each arm portion 20a is fixed.

The arm portion 20a is formed of a flexible member, and the arm portion 20a is provided with a latching portion 20b that detachably latches on the protrusion 34 of the upper unit 2. In FIG. 4, the cleaning member 16 is provided on the platen roller 25 so as to be housed in a groove on the outer periphery of the platen roller 25.

  Then, as shown in FIGS. 5 and 6, the bearing portions 19 and 20 of the platen roller unit 17 are inserted into the mounting portions 33 and 33 of the upper unit 2 with the conveying guide 18 disposed upward (see FIG. 5). 5).

  In this state, when the platen roller unit 17 is rotated 90 ° around the axis of the platen roller 25 (in the direction of the arrow in FIG. 5), the arm 20a bends and gets over the projection 34, and the latching portion 20b is fitted into the projection 34 ( (See FIG. 6). Thereby, the platen roller unit 17 can be easily attached to the upper unit 2.

  On the other hand, when removing the platen roller unit 17 from the upper unit 2, the arm 20 a is bent and the latching portion 20 b is removed from the protrusion 34, and then the platen roller unit 17 is subjected to a process reverse to the above-described attaching process. Can be easily removed from the upper unit 2. The platen roller unit 22 is detachably attached to the lower unit 1 as well as the upper unit 2 in the same manner as described above.

  FIG. 7 is a view showing a state in which the platen roller unit 17 is attached to the main body apparatus. When the platen roller unit 17 is attached to the main unit, the gear 32 on the main unit side meshes with the gear 31 fixed to the shaft 29 protruding from the end opposite to the light shielding part 26f of the platen roller 25. The gear 32a fixed to the motor shaft of the platen drive motor 15 is meshed with the gear 32a. Accordingly, the platen roller 25 is rotationally driven by the drive of the platen drive motor 15.

  As a result, the light shielding portion 26f formed on the platen roller 25 can enter a position where the light receiving portion of the platen roller rotational position detection sensor 35 can be shielded, and the control circuit 900 (see FIG. 9) recognizes the rotational position of the platen roller 25. Thus, the rotation operation of the platen roller 25 can be controlled.

  That is, the control circuit 900 detects the rotational position of the platen roller 25 with reference to the time point when the output of the platen roller rotational position detection sensor 35 is changed by the light shielding portion 26f attached to the platen roller 25. Thereafter, by driving the platen drive motor 15 by a specified amount, the platen roller 25 can be rotated to an arbitrary position.

  FIG. 9 is a schematic block diagram of a control system of the image reading apparatus. A control circuit 900 records a CPU 901 that controls the entire apparatus, a ROM 902 that stores control programs and data, and data and image data that control programs. A RAM 903 is provided.

  The control circuit 900 includes skew detection sensors 40 and 41 that detect skew of the document, a registration sensor 14 that detects the leading and trailing edges of the document, and a platen roller rotation position detection that detects the rotation position of the platen roller 25. A sensor 35 is connected.

  The control circuit 900 is connected to a reading sensor 12 that reads an image of the conveyed document 8, a pickup driving motor 905 that drives the pickup roller 6, and a platen driving motor 15 that drives the platen roller 25.

  Next, an example of calculating the skew amount of the trailing edge of the document 8 by the control circuit 900 will be described with reference to FIG. The skew amount is calculated as a delay time when the trailing edge of the skewed document is delayed due to skew, but is not limited thereto, and may be an angle, a distance, or the like.

  First, the skew detection sensors 40 and 41 are both optical reflective sensors, and are arranged on the upstream side of the registration sensor 14 provided at the center in the width direction of the conveyance path, as shown in FIG. A skew of the trailing edge of the document 8 is detected.

  The skew detection sensor 40 is spaced from one side in the width direction of the document 8 (left side in FIG. 8) with respect to the registration sensor 14, and the skew detection sensor 41 is spaced from the registration sensor 14 in the width direction of the document 8. The other side (the right side in FIG. 8) is spaced apart. In addition, the distance between the skew detection sensors 40 and 41 from the registration sensor 14 is the same.

  In FIG. 8, when the document 8 is skewed, first, one skew detection sensor 40 detects the trailing edge of the document 8. Next, the document 8 is conveyed, and the other skew detection sensor 41 detects the trailing edge of the document 8.

  Here, the distance between the skew detection sensors 40 and 41 is L, the conveyance speed of the document 8 is S, the difference between the detection times of the skew detection sensors 40 and 41 is T, the width of the conveyance path is W, and the document with the maximum width. That is, until the corner of the trailing edge of the document that is inclined and delayed from the time when the registration sensor 14 detects the trailing edge of the document having the same width as the conveyance path reaches the same position as the registration sensor 14 in the conveyance direction. When the time is T ′, the relationship L: ST = W / 2: ST ′ is established, and T ′ = (T · W) / (2L) is derived from the relationship.

  That is, the control circuit 900 calculates the time T ′, and the time T ′ + (distance between the registration sensor 14 and the platen roller 25 / S) from the time when the registration sensor 14 detects the trailing edge of the document 8. After the elapse of time, the platen roller 25 is rotated to clean the reading surface of the reading sensor 12 by the cleaning member 16 attached to the platen roller 25, and the platen roller 25 is set to a preset background color member (white The member 27 or the black member 26) is stopped at a position facing the reading sensor 12, and the platen drive motor 15 is controlled so as to hold the stopped state. Note that the rotation of the platen roller 25 may be started earlier than the above in consideration of the delay time from the start of the rotation of the platen roller 25 until the cleaning member 16 actually performs the cleaning.

  At this time, the control circuit 900 controls the pickup driving motor 905 to adjust the feeding timing of the pickup roller 6 so that the next document does not reach the platen roller 25. Note that, in an image reading apparatus that does not include a pickup roller, the feeding roller serves as a sheet feeding unit, and thus the same operation can be performed by adjusting the feeding start timing of the feeding roller.

  As described above, in this embodiment, even when the document 8 is skewed by detecting the skew of the trailing edge of the document 8, the reading by the cleaning member 16 is performed at a timing delayed according to the skew amount. Cleaning operation of the reading surface of the sensor 12, rotation operation of the platen roller 25 for stopping a preset background color member (white member 27 or black member 26) at a position facing the reading sensor 12, and feeding of the next document The operation can be started.

  As a result, the document can be prevented from being damaged, jammed, and the like, the delay of each operation timing can be minimized, and the number of read sheets per unit time can be reduced when the document skews. Can be minimized.

  When the document is not skewed, the cleaning member 16 cleans the reading surface of the reading sensor 12 and reads a preset background color member (white member 27 or black member 26) at the shortest timing. The rotation operation of the platen roller 25 stopped at a position facing the sensor 12 and the feeding operation of the next original can be started.

  Next, an image reading apparatus according to the second embodiment of the present invention will be described with reference to FIGS. In addition, about the part which overlaps with respect to the said 1st Embodiment, a code | symbol is diverted and demonstrated.

  In the first embodiment, the platen roller 25 is rotated, the cleaning surface of the reading sensor 12 is cleaned by the cleaning member 16, and the white member 27 or the black member 26 of the platen roller 25 is at a position facing the reading sensor 12. Assuming that the time taken to stop is Tr, after the time T ′ + (distance between the registration sensor 14 and the platen roller 25 / S) + Tr has elapsed since the registration sensor 14 detected the trailing edge of the document 8, It can be seen that the cleaning of the reading surface of the reading sensor 12 by the cleaning member 16 is completed.

  Here, in the present embodiment, the control circuit 900 has a time of T ′ + (distance between the registration sensor 14 and the platen roller 25 / S) + Tr (distance between the platen roller 25 and the pickup roller 6 / S). If the time is less than the time, the cleaning surface of the reading sensor 12 is cleaned by the cleaning member 16 as in the first embodiment, but T ′ + (distance between the registration sensor 14 and the platen roller 25 / S) + Tr Is longer than the time (distance between the platen roller 25 and the pickup roller 6 / S), the platen drive motor 15 is controlled so that the cleaning surface of the reading sensor 12 is not cleaned by the cleaning member 16. If the position of the pickup roller 6 is different from the position of the front end of the document, a determination is made in consideration thereof.

  That is, if the amount of skew of the document 8 is too large, it is necessary to sufficiently widen the time interval until the next document is fed, and the rate of decrease in the number of read sheets per unit time becomes large. When the amount is too large, the reading sensor 12 is not cleaned by the cleaning member 16, the skew amount of the document 8 is relatively small, and the cleaning of the reading sensor 12 by the cleaning member 16 can be completed within a specified paper feed interval. Only if the cleaning is performed. Since the time Tr for cleaning the reading sensor 12 is preferably shorter, it is desirable that the rotation speed of the platen roller 25 is relatively faster than the speed of the document being conveyed. In consideration of the delay from the start of rotation of the platen roller 25 until the cleaning member 16 actually performs cleaning, as in the first embodiment, when the rotation of the platen roller 25 can be started earlier, The above determination may be made accordingly.

  As described above, in this embodiment, when the skew amount of the original 8 is too large, the reading sensor 12 is not cleaned by the cleaning member 16, and therefore the reduction rate of the number of readings per unit time is reduced. Can do. Other configurations and operational effects are the same as those of the first embodiment.

  In the present embodiment, the skew amount of the document 8 is calculated, and when the skew amount increases as described above, the cleaning of the reading sensor 12 is not performed by the cleaning member 16. Thus, the skew amount of the document 8 is not calculated, and only the presence / absence of the skew exceeding the predetermined skew amount is detected. When the skew is detected, the cleaning of the reading sensor 12 by the cleaning member 16 is performed. It may not be performed.

  In this embodiment, the cleaning member is attached to the platen roller. However, the present invention is not limited to this. For example, the cleaning member is moved between a position where the cleaning member is brought into contact with the surface of the reading sensor and a position where the cleaning member is not brought into contact therewith. A mechanism may be provided.

  In this case, if the time taken from driving the moving mechanism until the cleaning of the surface of the reading sensor by the cleaning member is Tr, the time T ′ + (distance between the registration sensor 14 and the cleaning position / S) + Tr When the time of (distance between the cleaning position and the pickup roller 6 / S) is exceeded, the surface of the reading sensor is not cleaned by the cleaning member.

  Next, an image reading apparatus according to the third embodiment of the present invention will be described with reference to FIG. In addition, about the part which overlaps with the said 1st and 2nd embodiment, a code | symbol is diverted and demonstrated.

  In the present embodiment, a cleaning mode setting screen as shown in FIG. 10 is displayed on the operation display section of the image reading apparatus or the display section of an external control device (such as a PC) connected to the image reading apparatus.

  In the setting screen of FIG. 10, when “cleaning even when skew is detected” (hereinafter referred to as “cleaning priority mode”) is selected, the control circuit 900 performs the skew according to the control of the first embodiment. When the cleaning is performed at different timings according to the amount of lines, and "do not perform cleaning when the amount of skew is large" (hereinafter referred to as speed priority mode) is selected, the control circuit 900 performs the second implementation. Control the form. Note that the speed priority mode may be “no cleaning is performed when skew is detected”. Thus, in this embodiment, since the cleaning priority mode and the speed priority mode can be selected, the convenience for the user can be improved.

  Next, an image reading apparatus according to a third embodiment of the present invention will be described with reference to FIG. In addition, about the part which overlaps with respect to the said 1st Embodiment, a code | symbol is diverted and demonstrated.

  With reference to FIG. 11, an example of calculating the skew amount of the trailing edge of the document 8 by the control circuit 900 in the present embodiment will be described.

  In the figure, when the document 8 is skewed, first, one skew detection sensor 40 detects the trailing end of the document 8 as in the first embodiment. Next, the document 8 is conveyed, and the other skew detection sensor 41 detects the trailing edge of the document 8.

  Here, the distance between the skew detection sensors 40 and 41 is L, the conveyance speed of the document 8 is S, and the difference between the detection times of the skew detection sensors 40 and 41 is T, which is detected by a document width detection sensor (not shown). The dimension from the registration sensor 14 to the left edge of the document 8 is W1, and the dimension from the registration sensor 14 to the right edge of the document 8 is W2.

  The time from when the trailing edge of the document 8 is detected by the registration sensor 14 until the right corner of the trailing edge of the document 8 that is inclined and delayed reaches the same position as the registration sensor 14 with respect to the transport direction is defined as T. Then, the relationship L: ST = W2: ST ′ is established, and T ′ = (T / W2) / L is derived from the relationship.

  That is, the control circuit 900 calculates the time T ′, and the time T ′ + (distance between the registration sensor 14 and the platen roller 25 / S) from the time when the registration sensor 14 detects the trailing edge of the document 8. After the elapse of time, the platen roller 25 is rotated to clean the reading surface of the reading sensor 12 by the cleaning member 16 attached to the platen roller 25, and the platen roller 25 is set to a preset background color member (white The member 27 or the black member 26) is stopped at a position facing the reading sensor 12, and the platen drive motor 15 is controlled so as to hold the stopped state.

  At this time, the control circuit 900 controls the pickup driving motor 905 to adjust the feeding timing of the pickup roller 6 so that the next document does not reach the platen roller 25. When the document 8 is skewed in the opposite direction and the left side in the width direction of the document 8 is delayed, W1 is used instead of W2.

  As described above, in this embodiment, the width of the document 8 is detected by the document width detection sensor, and the passing time of the document 8 skewed according to the document width is calculated and controlled. The timing adjustment of the cleaning operation of the reading surface of the sensor 12, the rotation operation of the platen roller 25 that stops the white member 27 or the black member 26 at a position facing the reading sensor 12, and the feeding operation of the next original are performed with high accuracy. be able to. Other configurations and operational effects are the same as those of the first embodiment.

  In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

  For example, in the above-described embodiment, the skew amount is obtained by measuring the difference T between the detection times of the skew detection sensors 40 and 41. However, the skew detection sensor has a time interval corresponding to a predetermined skew amount. The presence or absence of skew exceeding a predetermined skew amount may be detected by a method of detecting a document at 40, 41 or the like. If the other skew detection sensor does not detect the trailing edge of the document even after a predetermined time has elapsed after one of the skew detection sensors 40, 41 detects the trailing edge of the document, the detection operation is terminated. The skew may be determined to be greater than the skew amount.

  Alternatively, simple control may be performed such that the timing of rotating the platen roller or the paper feed timing is changed for a predetermined time when a skew equal to or greater than a predetermined skew is detected.

  In the above-described embodiment, the registration sensor and the skew detection sensor are separately provided in order to accurately calculate the reading start position and the like. However, the registration sensor is not provided, and the skew detection sensor functions as the registration sensor. It is possible to substitute. For example, by averaging the detection timings of the two skew detection sensors, it may be the timing at which the leading edge and the trailing edge of the document to be detected by the registration sensor are detected.

  In addition, the arrival timing of the document to the reading sensor may be changed by adjusting the rotation speed of the feeding roller and the conveying roller. Alternatively, the conveyance roller immediately before the reading sensor may be a registration roller that can be temporarily stopped by controlling the stop time.

  The object of the present invention is achieved by executing the following processing. That is, a storage medium that records a program code of software that realizes the functions of the above-described embodiments is supplied to a system or apparatus, and a computer (or CPU, MPU, etc.) of the system or apparatus is stored in the storage medium. This is the process of reading the code.

  In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the program code and the storage medium storing the program code constitute the present invention.

  Moreover, the following can be used as a storage medium for supplying the program code. For example, floppy (registered trademark) disk, hard disk, magneto-optical disk, CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD + RW, magnetic tape, nonvolatile memory card, ROM or the like. Alternatively, the program code may be downloaded via a network.

  Further, the present invention includes a case where the function of the above-described embodiment is realized by executing the program code read by the computer. In addition, an OS (operating system) running on the computer performs part or all of the actual processing based on an instruction of the program code, and the functions of the above-described embodiments are realized by the processing. Is also included.

  Furthermore, a case where the functions of the above-described embodiment are realized by the following processing is also included in the present invention. That is, the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. Thereafter, based on the instruction of the program code, the CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing.

DESCRIPTION OF SYMBOLS 1 Lower unit 2 Upper unit 3 Conveyance roller 4 Feeding roller 5 Paper discharge roller 6 Pickup roller 7 Document base 8 Document 9 Paper discharge tray 11 Separation roller 12 Reading sensor 13 Hinge 14 Registration sensor 15 Platen drive motor 16 Cleaning member 17 Platen roller Unit 18 Transport guides 19 and 20 Bearing portion 20a Arms 21a and 22a Spacer 25 Platen roller 26 Black members 26a, 26c and 26e Insertion portion 26f Light shielding portion 27 White members 27a, 27c and 27e Insertion portion 29 Shafts 31, 32a and 32 Gears 33 Attaching part 35 Platen roller rotation position detection sensor 40, 41 Skew detection sensor 900 Control circuit 905 Pickup drive motor

Claims (4)

A reading sensor reads the image of originals to be conveyed,
A rotary member that are opposed to the reading sensor,
Rotation drive means for rotating the rotation member;
A cleaning member that has one end fixed to the rotating member and the other end protruding from an outer peripheral portion of the rotating member, and contacts the reading sensor when the rotating member rotates to clean the surface of the reading sensor. ,
Wherein the outer peripheral portion of the rotary member is provided with a groove, when said rotary member is rotated and the cleaning member is in contact with the reading sensor, and wherein the cleaning member is received in said groove An image reading apparatus. It said rotating member includes a semi-cylindrical black member and semicylindrical white member is engaged against said cleaning member, that said black member and the white member is attached to protrude from the joining portion to be joined The image reading apparatus according to claim 1. And controls the pre-Symbol rotation drive means, according to claim 1 or, characterized in that further comprising a controller for stopping said black member or the white member of the background color set in advance at a position opposite to the reading sensor 3. The image reading apparatus according to 2. Wherein the control unit includes an image reading apparatus according to claim 3, wherein the black member of the previous SL rotating member and controls the rotation driving means so that the position opposing the reading sensor.

Images