JP2009272711A - Image reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect that a read means has reached a read position by a single sensor, in an image reader capable of reading images by both flat head and sheet through systems. <P>SOLUTION: The image reader includes a movable read means 34 for reading images and a single detection means 32 for detecting a means 41 to be detected provided in the read means 34 for the position control of the read means 34, wherein a read position and a standby position are set in the order from one end side of the moving area of the read means 34, and the read means 34 is controlled so as to stand still at the read position and perform read when reading a moving original. The means 41 to be detected includes a first zone for outputting a first signal from the detection means when the read means 34 is positioned at the standby position, a second zone for outputting the first signal from the detection means 32 when the read means 34 is positioned at the read position, and a third zone positioned between the first zone and the second zone, for outputting a second signal from the detection means 32. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image reading apparatus, and in particular, in an image reading apparatus capable of reading an image by both a flat bed method and a sheet-through method, a single sensor detects that a carriage has reliably reached a reading position. The present invention relates to an image reading apparatus capable of performing the above.

  Conventionally, as the main image reading method by the image reading apparatus, a flat bed method in which a document is placed on a platen glass and the document image is read by a reading means that moves below the platen glass, and a plurality of documents are sequentially conveyed. However, there is a sheet-through method in which a document image is read by reading means fixed at a reading position. Generally, in the above-described image reading apparatus capable of reading both types, the reading position is different for each method, and the reading means (carriage) is arranged at a predetermined standby position when the power is turned on or after reading is completed. Yes. Therefore, a carriage detection sensor (HP sensor) is provided to control movement of the carriage to each position. In particular, in an image reading apparatus designed to reduce costs, the number of carriage detection sensors is limited to one, and carriage position control is performed based on the detection result of the single sensor.

  FIG. 9 is a schematic diagram for explaining carriage position control by a single sensor in a conventional image reading apparatus. Here, for ease of explanation, in the present specification, in the flat bed mode, the direction in which the original is read (right direction in FIG. 9) is the original reading direction, and in the flat bed mode, the carriage is retracted after the original is read. (Left direction in FIG. 9) is referred to as a carriage retracting direction.

  As shown in FIG. 9, a sensor 132 (here, a reflective sensor as an example) for detecting the carriage 134 is disposed in the scanner unit 120 of the image reading apparatus. The carriage 134 is provided with a flag 141 as a detected means at a position detected by the carriage detection sensor 132. This flag 141 is formed long in the sub-scanning direction. Here, the end on the carriage retracting direction side is a, and the end on the document reading direction side is b.

  The carriage 134 is provided to reciprocate in the sub-scanning direction. Here, an area in which the carriage 134 can reciprocate is defined as a carriage movement area W. The carriage detection sensor 132 detects the carriage 134 when the power of the image reading apparatus is turned on. At this time, in the carriage movement area W, the end a of the flag 141 is the sensor detection position C in the drawing. In the case where it is closer to the carriage retracting direction, the carriage detection sensor 132 detects the flag 141 and outputs an ON signal. In addition, when the end portion a of the flag 141 is present on the document reading direction side from the sensor detection position C in the drawing, the flag 141 is not detected by the carriage detection sensor 132 and the carriage detection sensor 132 outputs an OFF signal. . For this reason, the length of the flag 141 is long enough that the carriage detection sensor 132 remains in the ON state even when the carriage 134 is moved to the maximum in the carriage retracting direction. Here, a region where the carriage detection sensor 132 detects the flag 141 is a detection region A, and a region where the flag 141 is not detected is a non-detection region B. The standby position H of the carriage 134 (the position where the carriage waits until the reading operation is started after the apparatus is turned on) corresponds to a predetermined number of pulses of the stepping motor that drives the carriage in the carriage retracting direction from the sensor detection position C. It is set to a position separated by a distance.

  As an example of carriage position control in the conventional image reading apparatus as described above, initial processing for moving the carriage 134 to the standby position H when the power is turned on will be described.

  First, as shown in FIG. 10A, when the carriage 134 (the end a of the flag 141) is located in the detection area A when the power is turned on, the output of the carriage detection sensor 132 is turned on. Therefore, the carriage 134 is once moved in the document reading direction to move to the non-detection area B, and the carriage detection sensor 132 is turned off. Then, the carriage 134 is moved in the carriage retracting direction. After the carriage detection sensor 132 is turned on again, the movement of the carriage 134 is stopped with a predetermined pulse.

  Next, as shown in FIG. 10B, when the carriage 134 (the end a of the flag 141) is positioned in the non-detection area B when the power is turned on, the output of the carriage detection sensor 132 is turned off. Therefore, the carriage 134 is moved in the carriage retracting direction, and the carriage 134 stops moving with a predetermined pulse after the carriage detection sensor 132 is turned on.

After these operations, in the ADF mode, the carriage 134 is moved from the standby position H to the ADF reading position E in the carriage retracting direction to read the image. An image reading apparatus that controls the position of the carriage as described above is disclosed in, for example, Japanese Patent Application Laid-Open No. H10-228707.
Japanese Patent Publication No. 06-0669203

  However, in the case of the carriage position control in the conventional image reading apparatus as described above, the carriage detection sensor 132 is always ON while the carriage 134 is moving from the standby position H to the ADF reading position E. The carriage detection sensor 132 cannot confirm whether the carriage 134 has actually moved to the ADF reading position E. That is, both the case where the carriage 134 has actually moved to the ADF reading position E and the case where the carriage 134 has not moved to the ADF reading position E for some reason, such as failure of the motor or failure of the carriage lock during transportation. Since the carriage detection sensor 132 maintains the ON state, the apparatus cannot distinguish between these states. For this reason, even when the carriage 134 does not reach the ADF reading position E, the reading sensor is driven to perform a reading operation as if it has reached the ADF reading position E. Of course, if the carriage 134 does not reach the ADF reading position E, the original image cannot be read. In some cases, a plurality of useless printed materials that have failed to be read are generated.

  In order to avoid such a reading error, it is conceivable to provide a carriage detection sensor at the ADF reading position E as well. However, if the number of sensors is increased, the cost naturally increases, and the image reading apparatus using the single sensor as described above deviates from the original eye.

  In view of the above-mentioned conventional problems, the present invention is an image reading apparatus capable of reading an image by both a flat bed method and a sheet through method, and confirms that the carriage has reached the reading position with a single sensor. It is an object of the present invention to provide an image reading apparatus capable of detecting.

  In order to solve the above problems, the present invention provides a single unit for detecting a movable reading means for reading a document and a detected means attached to the reading means for controlling the position of the reading means. Detecting means, and a reading position and a standby position are set in order from one end side of the moving area of the reading means, and the reading means stops reading at the reading position when reading a moving document. An image reading apparatus controlled to perform, wherein the detected means includes a first area for outputting a first signal from the detecting means when the reading means is located at the standby position, and the reading A second section for outputting the first signal from the detection means when the means is located at the reading position; and a second section located between the first section and the second section from the detection section. Output the signal of 3 and zones, to provide an image reading apparatus, characterized in that it is composed of.

  The image reading apparatus further includes a control unit that controls movement of the reading unit, and the control unit receives the second signal from the detection unit immediately after the power is turned on. Is moved in the sub-scanning direction by a distance corresponding to the length of the third section in the sub-scanning direction, and the movement of the reading unit is controlled according to whether or not the output signal of the detection unit is changed by the movement. It is good to be.

  Specifically, by moving the reading unit in the sub-scanning direction by a distance corresponding to the length of the third section in the sub-scanning direction, the output signal of the detection unit is changed from the second signal to the first signal. When the signal is changed, the control means moves the reading means toward the other end side.

  When the output signal of the detection means maintains the second signal by moving the reading means in the sub-scanning direction by a distance corresponding to the length of the third section in the sub-scanning direction, The control means moves the reading means toward one end side.

  When the control means receives the first signal from the detection means after power is turned on, the control means moves the reading means toward the other end side.

  It is preferable that the first area and the second area are areas detected by the detection means, and the third area is an area not detected by the detection means.

  According to the image reading apparatus of the present invention, in the image reading apparatus capable of reading an image by both the flat bed system and the sheet through system, the carriage is set to the detection position (flag) of the sensor provided on the carriage. A first area for outputting a first signal from the carriage detection sensor when the carriage is at a position, a second area for outputting the first signal from the carriage detection sensor when the carriage is at the reading position, and the first area and the first area. Since the third area is located between the two areas and outputs the second signal from the carriage detection sensor, even the single carriage detection sensor detects the position of the carriage from the transition of the output, and the carriage reads it. It is possible to detect that the position has been reached reliably. In addition, structurally, there is an advantage that it is very easy to apply to an existing apparatus because of a simple configuration that can be realized only by providing a notch in the flag of the conventional apparatus.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall cross-sectional view showing a configuration of an image reading apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic top view showing a first carriage in the image reading apparatus. As shown in FIG. 1, the image reading apparatus 10 of the present invention includes a scanner unit 20 and a document conveying unit 50.

  The scanner unit 20 is provided with a box-shaped frame 31 having an opening in the upper part, a platen glass 33 for placing a document, a window 38 for reading a document in the ADF mode, and a projection. A contact member 39 (see FIG. 4) is provided. Further, a carriage detection sensor (reflection type sensor) 32 is disposed in the frame 31, and reading for reading a document transported from the document transport unit 50 or a document placed on the platen glass 33. The mechanism is housed.

  The reading mechanism illuminates the original and transmits a reflected optical system 34 (reading means) 34 (first carriage 34A and second carriage 34B), and condenses the reflected light from the original. Lens 36 and an image sensor 37 as photoelectric conversion means.

  The first carriage 34A is configured such that a lamp 341 for irradiating light on a document and a first mirror 342 for further reflecting light reflected on the document are mounted on a carriage frame 343 as shown in FIG. Is done. On the side surface of the carriage frame 343, a flag (detected means) 41 that is long in the sub-scanning direction is provided at a position detected by the carriage detection sensor 32. Further, the second carriage 34B is mounted with a second mirror 344 and a third mirror 345 for further reflecting the light from the document reflected by the first mirror 342 of the first carriage 34A toward the lens 36. ing. The first carriage 34A and the second carriage 34B are provided inside the frame 31 so as to be capable of reciprocating in the sub-scanning direction along the lower surface of the platen glass 33.

  Next, the document conveying unit 50 is installed on the upper part of the scanner unit 20 so that the surface of the platen glass 33 of the scanner unit 20 can be opened and closed by a hinge. The document transport unit 50 is provided with a sheet feed stacker 51 for stacking and storing documents, roller groups 52 to 56 for feeding and discharging documents, and a sheet discharge tray 57 for collecting discharged documents. .

  In the ADF mode in which a document transported by the document transport unit 50 is read, the documents on the paper feed stacker 51 are separated and fed one by one by a paper feed roller 52, a registration roller pair 53, then a transport roller 54, It is conveyed to a predetermined reading position by the rotation of 55. In the scanner unit 20, the first carriage 34A is stopped at a predetermined reading position set below the ADF reading window 38 from the standby position H, and the second carriage 34B is stopped in the vicinity thereof. Irradiate light. The reflected light passes through the first mirror 342, the second mirror 344, and the third mirror 345, is collected by the lens 36, is photoelectrically converted by the image sensor 37, and is subjected to various image processing and is then processed as image data. Is output. The document that has been read is discharged onto the discharge tray 57 by the rotation of the discharge roller 56.

  In the flat bed mode in which the document placed on the platen glass 33 is read, the light from the lamp 341 is irradiated onto the document while moving the carriage 34 of the scanner unit 20 along the platen glass 33 in the document reading direction. And read. Other operations of the scanner unit 20 are the same as those in the ADF mode. When the reading is completed, the carriage 34 is retracted to the standby position H and stops moving.

  In the present invention, in the image reading apparatus 10 as described above, a notch 413 as shown in FIG. 2 is formed in the flag 41 provided on the first carriage 34A in order to control the position of the carriage 34 with certainty. If the end of the flag 41 in the carriage retracting direction is a and the end in the document reading direction is b, the a side is the first detected portion 411 and the b side is the second detected portion 412 with the notch 413 interposed therebetween. In the present invention, the carriage 34 reaches the ADF reading position E from the standby position H by detecting the three detected parts 411, 412, and 413 including the notch (third detected part) 413 by the carriage detection sensor 32. Determine if you did.

  Here, a circuit configuration for realizing the present invention will be described. FIG. 3 is a block diagram showing a circuit configuration of the image reading apparatus according to the embodiment of the present invention. As shown in FIG. 3, the image reading apparatus 10 has a configuration in which a CPU 61, ROM 62, RAM 63, lamp 341, carriage drive motor 64, carriage detection sensor 32, and image sensor 37 are connected to each other via a bus 65.

  The CPU 61 controls the entire apparatus according to a program stored in the ROM 62 as a control unit. The ROM 62 includes a flash memory and stores programs and data necessary for the operation of the image reading apparatus 10. The RAM 63 is composed of SRAM, DRAM, and the like, and is a storage means for temporarily storing data generated when the program is executed, and is used as a work area for the CPU 61.

  Various drive motors, sensors, and the like are connected to the CPU 61. In this embodiment, the lamp 341, the carriage drive motor 64, the carriage detection sensor 32, and the image sensor 37 are connected, and the CPU 61 controls them. Specifically, the lighting control of the lamp 341 via the inverter and the drive control of the image sensor 37 are performed. Further, the carriage drive motor 64 is controlled via a driver to control the drive of the carriage 34. In addition to carriage detection control by the carriage detection sensor 32, drive control of the carriage drive motor 64 based on an ON / OFF signal output from the carriage detection sensor 32 is also performed.

  Next, a specific operation at the time of carriage detection by the image reading apparatus according to the present embodiment will be described in detail. FIG. 4 is a schematic front view of the image reading apparatus according to the embodiment of the present invention, and FIG. 5 is an enlarged view of a main part thereof. In FIG. 4, W indicates a moving area of the first carriage 34A. The carriage movement area W is divided into a detection area A and a non-detection area B by the sensor detection position C. When the end a of the flag 41 is located in the detection area A, the carriage detection sensor 32 detects the first detected part 411 or the second detected part 412 of the flag 41 and outputs an ON signal or a notch (first (3 detected portion) 413 faces the sensor detection position C, so that the carriage detection sensor 32 outputs an OFF signal. The flag 41 is sufficiently long (secondary) so that the second detected portion 412 is detected by the carriage detection sensor 32 and the carriage detection sensor 32 is turned on even when the carriage 34 moves to the maximum in the carriage retracting direction. (Length in the scanning direction). On the other hand, when the end a of the flag 41 is located in the non-detection region B, the carriage detection sensor 32 outputs an OFF signal because the flag 41 is not detected.

  Here, each position in the carriage movement area W will be described. Note that the following positions are based on the position of the reading line r of the first carriage 34A.

  First, the lock position D is a fixed position when the movement of the carriage 34 is locked. When the apparatus is transported or the like, the carriage 34 is fixed to the frame 31 so as not to move to prevent breakage. When fixing, for example, as shown in FIG. 5 (a), the carriage 34 is moved to the lock position D, and then fixed in a recess 346 provided on the lower surface of the second carriage 34B so as to be able to move up and down. The entire carriage 34 is locked by inserting the member 70 from below.

  The ADF reading position E is a position for reading a document conveyed from the document conveying unit 50 in the ADF mode, and is set so that the reading line r is positioned under the window 38.

  The braking position F will be described with reference to FIG. If the locking process is performed in a state where the carriage 34 has not moved to the lock position D due to a user operation error or the like, the carriage 34 is not locked and only the fixing member 70 is inserted from below. . Of course, the carriage 34 remains movable, and when the carriage 34 is moved in the carriage retracting direction, the carriage retracting direction end of the second carriage 34B comes into contact with the fixing member 70. It becomes impossible to advance in the carriage retracting direction. Thus, the position where the carriage 34 is prevented from moving in the carriage retracting direction by the fixing member 70 due to an operation error or the like is set as a braking position F. The flag 41 of the carriage 34 is set with the length in the sub-scanning direction of each of the detected means 411, 412, and 413 so that the notch 413 is positioned at the sensor detection position C when the carriage 34 is at the braking position F. [See FIG. 6 (d)].

  The flat bed reading start position G is a position where reading is started in the flat bed mode in which the original on the platen glass 33 is read while the carriage 34 is driven in the original reading direction.

  The standby position H is a position where the carriage 34 waits until the reading operation is started after the image reading apparatus 10 is powered on. The standby position H is set at a position separated from the sensor detection position C by a distance l corresponding to a predetermined number of pulses of the carriage drive motor 64 in the carriage retracting direction.

  An initial process for placing the carriage 34 at the standby position H when the power is turned on will be described. FIG. 6 is a schematic diagram showing the detection status of the flag at each position of the carriage, and FIG. 7 is a flowchart showing the flow of initial processing for placing the carriage at the standby position H when the power is turned on. As shown in FIG. 6A, the width (the length in the sub scanning direction) of the first detected portion 411 of the flag 41 is s, and the width (the length in the sub scanning direction) of the second detected portion 412 is t. The width (length in the sub-scanning direction) of the notch 413 is u, and the total length (s + u + t) of the flag 41 is v.

  First, when the apparatus is turned on, the CPU 61 outputs the output of the carriage detection sensor 32 in order to confirm whether the carriage 34 (flag 41) is located in the detection area A or non-detection area B. Whether or not is ON is checked (step S1). When it is ON, it can be seen that the carriage 34 (flag 41) is located in the detection area A as shown in FIGS. 6 (b), 6 (c), 6 (e), and 6 (f). .

  At this time, the possibility is considered that the first detected portion 411 is located at the sensor detection position C as shown in FIGS. 6B and 6C, and FIG. e) A case where the second detected portion 412 is located at the sensor detection position C as shown in FIG. Therefore, the CPU 61 drives the carriage drive motor 64 to move the carriage 34 in the document reading direction by a distance equal to or longer than the total length v of the flag 41 (step S2). Then, regardless of whether the first detected portion 411 or the second detected portion 412 is located at the sensor detection position C, the flag 41 is reliably positioned in the non-detection region B by step S2. Therefore, it is confirmed whether or not the output of the carriage detection sensor 32 is turned off (step S3). In the case of YES, the flag 41 (carriage 34) is correctly positioned in the non-detection area B [see FIG. 6 (a)]. In the case of NO, since there is a high possibility that the carriage 34 has not moved from the position when the power is turned on for some reason, such as a failure of the carriage drive motor 64, an error display is performed (step S9).

  Next, the carriage 34 is moved in the carriage retracting direction (step S4). The movement of the carriage 34 is continued until the sensor output is turned on. When the sensor output is turned on (see step S5, FIG. 6B), the carriage drive motor 64 has a predetermined number of pulses (distance 1 in FIG. 4). Further, after the carriage 34 is moved in the carriage retracting direction, the carriage 34 is stopped (step S6). This position is a standby position H shown in FIG.

  On the other hand, when the output of the carriage detection sensor 32 is OFF in step S1, a possible state is when the carriage 34 (flag 41) is positioned in the non-detection region B as shown in FIG. This is one of cases where the notch 413 is located at the sensor detection position C as shown in d) [that is, the carriage 34 (flag 41) is located in the detection area A]. Therefore, in order to confirm which state is described above, the carriage 34 is moved in the document reading direction by the distance u of the width u of the notch 413 (step S7). Then, when the carriage 34 (flag 41) is located in the non-detection region B as shown in FIG. 6A, the output of the carriage detection sensor 32 remains OFF, but as shown in FIG. If the sensor detection position C is at the notch 413, the output of the carriage detection sensor 32 changes to ON. Therefore, it is confirmed again whether the output of the carriage detection sensor 32 is ON (step S8).

  When the output of the carriage detection sensor 32 is ON (that is, when there is a change in the output of the carriage detection sensor 32), the first detected portion 411 is located at the sensor detection position C. Move. When the output of the carriage detection sensor 32 is OFF (that is, when there is no change in the output of the carriage detection sensor 32), the carriage 34 (flag 41) is located in the non-detection area B. Is moved in the carriage retracting direction to perform the above-described processing. This completes the initial process of placing the carriage 34 at the standby position H.

  Next, processing when the carriage 34 is moved from the standby position H to the ADF reading position E in the ADF mode will be described. FIG. 8 is a flowchart showing the processing flow.

  When the user selects the ADF mode and instructs to start reading, first, the carriage 34 stopped at the standby position H shown in FIG. 6C is moved in the carriage retracting direction. At this time, the counting of the number of pulses x of the carriage drive motor 64 is also started (step S11). When the value obtained by replacing the distance n from the standby position H to the ADF reading position E with the number of pulses of the carriage drive motor 64 is P, the carriage 34 is driven until the number of pulses x of the carriage drive motor 64 reaches the predetermined value P. And keep moving. When the number of pulses x of the carriage drive motor 64 reaches the predetermined value P (step S12), the carriage drive motor 64 is stopped and the carriage 34 also stops moving (step S13).

  Here, when the carriage 34 is at the ADF reading position E, the length of each detected means of the flag 41 is set in advance so that the second detected portion 412 faces the sensor detection position C. That is, v> n + 1> s + u is set. Therefore, if the carriage 34 has normally moved to the ADF reading position E, the carriage detection sensor 32 detects the second detected portion 412. Therefore, it is next confirmed whether or not the output of the carriage detection sensor 32 is ON (step S14).

  Next, it is determined whether or not the output of the carriage detection sensor 32 has been turned off until the number of pulses x reaches the predetermined value P (step S15). Until the number of pulses x of the carriage drive motor 64 reaches a predetermined value P (until the carriage 34 reaches the ADF reading position E from the standby position H), at the sensor detection position C, the first detected portion 411, the notch Passing in the order of 413, the carriage 34 stops when the second detected portion 412 is positioned. Therefore, the output of the carriage detection sensor 32 changes to ON, OFF, ON until the number of pulses x of the carriage drive motor 64 reaches the predetermined value P. Therefore, if the output of the carriage detection sensor 32 is OFF before the number of pulses x reaches the predetermined value P, it can be seen that the carriage 34 has normally reached the ADF standby position E. Whether the output of the carriage detection sensor 32 has been turned off is determined in advance so that if the sensor output is turned off before the carriage 34 reaches the ADF reading position E from the standby position H, it is stored in the storage means (RAM 63). Since it is set, judgment is performed from here. Thus, it is confirmed from step S14 and step S15 that the carriage 34 has reached the ADF reading position E with certainty. Therefore, the document reading operation is started in step S16.

  On the other hand, if the output of the carriage detection sensor 32 is OFF in step S14, the carriage 34 stops at the braking position F as shown in FIG. 6D, and the notch 413 of the flag 41 is located at the sensor detection position C. State. As described above, the length of each detected means of the flag 41 is set in advance so that the notch 413 is positioned at the sensor detection position C when the carriage 34 is at the braking position F. That is, when the distance between the standby position H and the braking position F is m, s + u> m + 1> s is set. When the carriage 34 is at the braking position F, the carriage 34 can no longer move in the carriage retracting direction, and even if the reading operation is performed in this state, an original image cannot be acquired. (Step S17).

  If the sensor output is not OFF in step S15, there is a high possibility that the carriage 34 has not moved from the standby position H for some reason, such as a failure of the carriage drive motor 64. Therefore, in this case as well, the reading operation is not performed and error display is performed (step S17). This completes the processing for moving the carriage 34 from the standby position H to the ADF reading position E in the ADF mode.

  In the present embodiment, the three detected portions 411, 412, and 413 of the flag 41 are configured by one member, but these may be formed by a plurality of members. Further, in the present embodiment, the third detected unit 413 is formed by cutting out a part of the flag 41. For example, the third detected unit 413 includes the first detected unit 411 and the second detected unit 412. May be formed from members having different transmittances. In short, any configuration may be used as long as the output of the carriage detection sensor 32 is different between the first detected unit 411 and the second detected unit 412 and the third detected unit 413.

  Further, in the present embodiment, an example in which the lock position D and the standby position H of the carriage 34 are different is shown. However, even if the configuration is such that these are set at the same location, the ADF reading position is detected from the output change of the carriage detection sensor 32. It can be determined whether or not the carriage 34 has moved to E.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, Based on the meaning of this invention, various deformation | transformation are possible, These are excluded from the scope of the present invention. is not.

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus capable of reliably detecting that a carriage has reached a reading position with a single sensor in an image reading apparatus capable of reading an image using both a flat bed system and a sheet through system. Have industrial applicability.

1 is an overall cross-sectional view illustrating a configuration of an image reading apparatus according to an embodiment of the present invention. FIG. 3 is a schematic top view showing a first carriage in the image reading apparatus according to the embodiment of the present invention. 1 is a block diagram illustrating a circuit configuration of an image reading apparatus according to an embodiment of the present invention. 1 is a schematic front view of an image reading apparatus according to an embodiment of the present invention. 1 is an enlarged view of a main part of an image reading apparatus according to an embodiment of the present invention. FIG. 5 is a schematic diagram illustrating a flag detection state at each position of a carriage of the image reading apparatus according to the embodiment of the present invention. 6 is a flowchart illustrating a flow of an initial process for arranging a carriage at a standby position H when the image reading apparatus according to the embodiment of the present invention is turned on. 6 is a flowchart illustrating a processing flow when the carriage is moved from a standby position to an ADF reading position in the ADF mode of the image reading apparatus according to the embodiment of the present invention. It is a schematic diagram for demonstrating the position control of the carriage by the single sensor in the conventional image reading apparatus. FIG. 10 is a schematic diagram for explaining processing for stopping a carriage at a standby position in a conventional image reading apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image reading device 20 Scanner unit 31 Frame 32 Carriage detection sensor 33 Platen glass 34 Carriage 34A 1st carriage 34B 2nd carriage 36 Lens 37 Image sensor 38 Window 39 Abutting member 41 Flag 50 Document conveyance unit 51 Paper feed stacker 52 Paper feed Roller 53 Registration roller pair 54, 55 Conveying roller 56 Discharging roller 57 Discharging tray 61 CPU
62 ROM
63 RAM
64 Carriage drive motor 65 Bus 70 Fixing member 341 Lamp 342 First mirror 343 Carriage frame 344 Second mirror 345 Third mirror 346 Recess 411 First detected part 412 Second detected part 413 Notch (third detected part)

Claims (6)

A movable reading means for reading a document; and a single detection means for detecting a detected means attached to the reading means for controlling the position of the reading means. A reading position and a standby position are set in order from one end side of the area, and the reading unit is an image reading apparatus controlled to read at a reading position while reading a moving document,
The detected means is
A first zone for outputting a first signal from the detection means when the reading means is located at the standby position;
A second zone for outputting the first signal from the detection means when the reading means is located at the reading position;
An image reading apparatus comprising: a third section located between the first section and the second section and outputting a second signal from the detection means. A control means for controlling movement of the reading means;
When the control means receives the second signal from the detection means immediately after power-on, the control means moves the reading means in the sub-scanning direction by a distance corresponding to the length of the third area in the sub-scanning direction. The image reading apparatus according to claim 1, wherein the movement of the reading unit is controlled according to whether or not the output signal of the detection unit is changed due to the movement.   When the output signal of the detection means changes from the second signal to the first signal by moving the reading means in the sub-scanning direction by a distance corresponding to the length of the third section in the sub-scanning direction The image reading apparatus according to claim 2, wherein the control unit moves the reading unit toward the other end side.   When the output signal of the detection means maintains the second signal by moving the reading means in the sub-scanning direction by a distance corresponding to the length of the third section in the sub-scanning direction, the control means The image reading apparatus according to claim 2, wherein the reading unit is moved toward one end side.   3. The control unit according to claim 2, wherein, when the control unit receives the first signal from the detection unit after power-on, the control unit moves the reading unit toward the other end side. 4. The image reading apparatus described.   The image reading apparatus according to claim 1, wherein the first area and the second area are areas detected by the detection unit, and the third area is an area not detected by the detection unit.

Images