JP6337414B2 - Image reading device - Google Patents

Description

  The present invention relates to an image reading apparatus.

  2. Description of the Related Art Conventionally, there has been known an image reading apparatus that includes a document conveying unit that conveys a document and a reading unit that reads a document being conveyed. For example, in Patent Document 1, an image reading operation by the reading unit is performed during a period from when a document conveyance stop command such as a buffer full is satisfied and when a document conveying stop command is issued to the document conveying unit until the document is stopped. An image reading apparatus that continues the process is described. Thus, it is possible to perform reading even during the overrun of the document from when the stop command is issued until the document is actually stopped, and to obtain seamless image data.

JP-A-6-98102

  However, if the image reading operation is simply continued after the document conveyance stop command is issued until the document is stopped, the read image may be extended when the document is decelerated and stopped. there were. In the image reading apparatus described in Patent Document 1, the behavior of the original when the original is stopped different from that during the original conveyance is not taken into consideration.

  The present invention has been made in view of the above-described problems, and a main object of the present invention is to acquire image data obtained by accurately reading a document when the conveyance of the document is stopped.

  The present invention adopts the following means in order to achieve the above-mentioned object.

The image reading apparatus of the present invention includes:
An original conveying means for conveying an original in the conveying direction;
Driving means for driving the document conveying means;
Reading means for reading the original conveyed by the original conveying means;
When the driving unit drives the document conveying unit to convey the document, the reading unit is controlled to read the document being conveyed to acquire image data. When the driving unit pauses, the original is read by controlling the reading unit so that the reading time interval, which is the reading time interval related to the acquisition of image data, becomes longer than before the pause. Reading control means for obtaining the image data and then stopping the acquisition of the image data;
It is equipped with.

  In the image reading apparatus of the present invention, when the driving unit drives the document conveying unit to convey the document, the reading unit is controlled to read the document being conveyed and acquire image data. Then, when the driving unit pauses while the document is being conveyed, the reading unit is controlled so that the reading time interval, which is the reading time interval related to the acquisition of image data, becomes longer than before the pause. The image data is acquired by reading, and thereafter the acquisition of the image data is stopped. In this way, when the document conveying unit is decelerated and stopped immediately when the driving unit is temporarily stopped, the reading time interval is made longer than that before the driving unit is temporarily stopped. In addition, image data obtained by reading a document can be acquired. As a result, it is possible to acquire image data obtained by accurately reading a document when the conveyance of the document is stopped. Here, the “reading time interval” is “the reading time interval relating to acquisition of image data”. Therefore, for example, when all the image data read by the reading unit is acquired, the time interval at which the reading unit actually reads the document directly corresponds to the “reading time interval”. On the other hand, for example, when ignoring at least a part of the image data read by the reading unit (not acquired as image data representing a document), reading when focusing only on reading about the acquired image data (image data not ignored) Corresponds to the “reading time interval”. Therefore, “to make the reading time interval longer than that before the temporary stop” is not limited to making the reading time interval longer by increasing the time interval at which the reading unit actually reads the document. For example, it includes a method in which the reading time interval is increased by ignoring a part of the image data read by the reading means without changing the time interval at which the reading means actually reads the original. Similarly, “stop acquisition of image data” includes a case where the reading unit stops reading of the original and a case where reading of the original by the reading unit is not stopped but the read image data is ignored.

  In the image reading apparatus according to the aspect of the invention, the reading control unit may be configured such that when the driving unit pauses during conveyance of the document, the reading time interval tends to be gradually longer than before the pause. Image data may be acquired by controlling the reading unit to read the document. In this way, when the driving means is temporarily stopped, when the document conveying means does not stop immediately but stops while gradually decelerating, the reading time interval tends to become gradually longer. Reading is possible. As a result, it is possible to acquire image data obtained by accurately reading a document when the conveyance of the document is stopped. Here, “the tendency that the reading time interval relating to the acquisition of image data gradually increases” means that the reading time interval becomes longer as a linear function, a case where the reading time interval becomes longer as a quadratic function, Including those that become longer.

  In the image reading apparatus according to the aspect of the invention, when the driving unit pauses during conveyance of the document, the reading control unit stops acquiring the image data as the conveyance speed of the document before the suspension is higher. It is good also as what tends to become long time to. The faster the document transport speed, the longer the time until the document stops when the driving means is temporarily stopped. Therefore, by increasing the speed of stopping the acquisition of image data as the speed of transporting the original document before the driving unit is paused increases, the time taken to stop the acquisition of the image data is increased. Image data obtained by reading a document with higher accuracy can be acquired.

  In the image reading apparatus according to the aspect of the invention, when the driving unit pauses during conveyance of the document, the reading control unit displays the tendency of the reading time interval according to the document conveyance speed before the suspension. It may be changed. When the document transport speed is different, the behavior of the document when the driving unit is temporarily stopped is often different depending on the transport speed. In such a case, by changing the tendency of the reading time interval according to the conveyance speed of the document before the driving unit is temporarily stopped, the document is read with higher accuracy according to the conveyance behavior of the document when the driving unit is temporarily stopped. Acquired image data. In this case, when the driving unit pauses while the document is being conveyed, the reading control unit is configured such that the document conveyance speed before the pause is higher as the document conveyance speed before the pause is slower. The reading time interval after the temporary stop may be set to be longer than that. In addition, when the driving unit pauses while the document is being transported, the reading control unit is slower than the document transport speed before the pause as the document transport speed before the pause is slower. Thus, the change in the reading time interval when the reading time interval is gradually increased may be made steep.

  In the image reading apparatus of the present invention in which the processing according to the transporting speed of the document before the suspension of the driving unit described above is performed, the reading control unit may directly perform the processing according to the transporting speed. However, processing corresponding to the conveyance speed may be performed indirectly. For example, the processing according to the driving speed of the driving unit may be performed. In addition, it is possible to provide drive control means for controlling the drive means so that the document conveyance speed tends to be slower as the document reading resolution is higher, and the reading control means may perform processing according to the document reading resolution. Good. In this way, it is possible to acquire image data obtained by accurately reading a document according to the reading resolution when the conveyance of the document is stopped.

  In the image reading apparatus according to the aspect of the invention, the reading control unit may change the tendency of the reading time interval according to the type of the document or the type of the document when the driving unit pauses during conveyance of the document. The time until the acquisition of the image data is stopped may be changed or at least one of them may be performed. In this way, it is possible to obtain image data obtained by accurately reading a document when the behavior of document conveyance when the driving unit is temporarily stopped varies depending on the type of document.

  In the image reading apparatus of the present invention, the document conveying unit may transmit power from the driving unit to the document via a train wheel composed of a plurality of gears. In the case where the power from the driving means is transmitted to the document via a gear train composed of a plurality of gears, when the driving means is temporarily stopped, the document is not immediately stopped but is likely to be decelerated and stopped. The significance of applying is high.

  In the image reading apparatus according to the aspect of the invention, the driving unit serves as a unit that drives the document conveying unit and a unit that moves the reading unit in a moving direction, and the reading unit is placed on the document placement region. When reading the placed document, the document may be read while moving in the moving direction by the driving means. As described above, when the driving unit serves to drive the document conveying unit and to move the reading unit, the document conveying unit has a long train wheel composed of a plurality of gears. The position of is easy to leave. For this reason, when the driving means is temporarily stopped, the document is not immediately stopped but is likely to be decelerated and stopped, and the significance of applying the present invention is high. In this case, the conveyance direction and the movement direction may be the same direction or different directions.

  In the image reading apparatus of the present invention, the reading control unit controls the reading unit when the driving unit resumes driving the document conveying unit after the driving unit pauses during conveyance of the document. In acquiring the image data by reading the original, the acquisition of the image data may be resumed after the start of the operation of the driving unit. In this way, when the conveyance of the document after the suspension of the driving unit is resumed, the image data obtained by reading the document can be obtained with high accuracy if the conveyance of the document is not started immediately after the operation of the driving unit is started.

  The image reading apparatus according to the present invention may further include a drive control unit that temporarily stops the driving unit when a temporary stop condition is satisfied during conveyance of the document. In this case, a buffer that temporarily stores the acquired image data may be provided, and the temporary stop condition may be satisfied when the buffer becomes full. When the buffer for storing image data becomes full, it is necessary to pause the driving means during document conveyance to stop reading. Even in such a case, it is necessary to acquire image data obtained by accurately reading the document. Can do. Note that the temporary stop condition may be satisfied when the free space of the buffer is less than a threshold that can be regarded as close to the buffer full. The temporary stop condition may be satisfied when a failure or abnormality of the driving unit is detected.

The image reading method of the present invention includes:
A method for controlling an image reading apparatus, comprising: a document conveying unit that conveys a document in a conveying direction; a driving unit that drives the document conveying unit; and a reading unit that reads a document conveyed by the document conveying unit. ,
(A) when the driving unit drives the document conveying unit to convey the document, the reading unit is controlled to read the document being conveyed to acquire image data;
(B) When the driving unit pauses during conveyance of the document, the reading unit is controlled so that a reading time interval, which is a reading time interval related to acquisition of image data, becomes longer than before the pause. And acquiring the image data by reading the original, and then stopping the acquisition of the image data;
Is included.

  In the control method of the image reading apparatus according to the present invention, when the driving unit pauses during conveyance of the original, the reading unit is controlled to read the original so that the reading time interval becomes longer than before the temporary stop. The image data is acquired, and then the acquisition of the image data is stopped. As a result, as with the image reading apparatus of the present invention described above, it is possible to acquire image data obtained by accurately reading a document when the conveyance of the document is stopped. In the control method of the image reading apparatus, various aspects of the above-described image reading apparatus may be adopted, and steps for realizing each function of the above-described image reading apparatus may be added. .

  The program of the present invention causes one or more computers to realize each step of the above-described control method of the image reading apparatus. This program may be recorded on a computer-readable recording medium (for example, hard disk, ROM, FD, CD, DVD, etc.), or from a computer via a transmission medium (communication network such as the Internet or LAN). It may be distributed to another computer, or may be exchanged in any other form. If this program is executed by one computer or if each computer is assigned to each step and executed, each step of the above-described image reading apparatus control method is executed. An effect is obtained.

FIG. 2 is a configuration diagram illustrating an outline of a configuration of a multifunction printer 20. FIG. 2 is a configuration diagram showing an outline of the configuration of a scanner unit 40. The perspective view of the housing | casing cover 22 and the flat bed part 31. FIG. The perspective view of the flat bed part 31. FIG. AA sectional drawing of FIG. The top view of the enlarged part of FIG. Explanatory drawing which shows the internal structure of the ADF unit 61. FIG. Explanatory drawing which shows the internal structure of the ADF unit 61. FIG. B view of FIG. The enlarged view of the wavy line frame C of FIG. Explanatory drawing of reading time interval table 54a, 54b. 7 is a flowchart illustrating an example of an ADF image reading processing routine. Explanatory drawing which shows a mode that the process at the time of normal time and the process at the time of a pause are performed. Explanatory drawing which shows a mode that the process at the time of a restart and subsequent normal time process are performed.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing an outline of a configuration of a multifunction printer 20 according to an embodiment of the present invention. FIG. 2 is a configuration diagram showing an outline of the configuration of the scanner unit 40. FIG. 3 is a perspective view of the housing cover 22 and the flat bed portion 31. FIG. 4 is a perspective view of the flat bed portion 31.

  As shown in FIG. 1, the multi-function printer 20 of the present embodiment includes a housing 21 and a housing cover 22 that can open and close the upper surface of the housing 21, and a document S (see FIG. 2). A scanner unit 40 that optically reads and generates image data, a printer unit 42 that feeds, prints, and discharges paper set in a cassette (not shown) to the paper discharge tray 24, and various operations by the user And an operation panel 46 that can be controlled, and a main controller 80 that controls the entire apparatus. A glass table 32 is disposed on the upper surface of the housing 21, and a partial area of the glass table 32 is used as a flat bed (FB) reading region 35. A document placed in the FB reading area 35 is fixed by a document presser 22c provided on the housing cover 22, and can be optically read by the scanner unit 40 (hereinafter, this operation mode). Is called FB reading mode). The housing cover 22 incorporates an automatic document feeder unit 61 (hereinafter referred to as ADF unit 61) that automatically and automatically conveys the original S one by one (see FIG. 2), and FB reading of the glass table 32 is performed. An area different from the area 35 is used as the ADF reading area 34 for reading the document S automatically conveyed by the ADF unit 61. When the document S automatically conveyed by the ADF unit 61 passes through the opening 22a formed on the lower surface of the housing cover 22 and covered with a transparent film with the housing cover 22 being closed, The scanner unit 40 can pass through the reading area 34 and optically read (hereinafter, this operation mode is referred to as an ADF reading operation mode). Further, the opening 22a is opened with a larger opening width in the conveyance direction of the document S (the left-right direction in FIG. 2) than the ADF reading area 34. A white reference plate 36 for performing so-called shading correction is provided at the right end of the FB reading area 35 in the sub-scanning direction (the same direction as the transport direction) (see FIG. 2). Further, the foremost side of the right end portion in the sub-scanning direction of the FB reading area 35 in FIG. 1 is an FB reading origin 35a that is an original reading origin in the FB reading operation mode.

  The scanner unit 40 includes a scanner ASIC 50 and a scanner engine 60. The scanner ASIC 50 is an integrated circuit that controls the scanner engine 60. Upon receiving a scan command from the main controller 80, the scanner ASIC 50 reads the document as image data in either the FB reading mode or the ADF reading mode. To control.

  As shown in FIG. 2, the scanner engine 60 includes an ADF unit 61 that automatically transports a document S placed on the ADF paper feed tray 27 and set in the ADF insertion slot 26 to the ADF reading area 34, and a glass table 32 or ADF. A light source unit 71 that irradiates the reading area 34 with light, a contact image sensor (CIS) 74 that receives reflected light from the document S and stores it as charges, and a light source unit 71 and a CIS 74 are mounted. And a CIS module 76. The scanner engine 60 includes a carriage motor 78 configured as a stepping motor that is fixed to the lower side of the casing of the CIS module 76 and moves together with the CIS module 76, and motor gears 78 a, 78 b, 78 c that are rotationally driven by the carriage motor 78. A guide gear 79 disposed in the sub-scanning direction. The scanner engine 60 includes a main body side gear mechanism 90 driven by a carriage motor 78 and a cover side gear mechanism 95. The motor gear 78a meshes with the motor gear 78b, the motor gear 78b meshes with the motor gear 78c, and the motor gear 78c meshes with the guide gear 79. The motor gear 78c is formed by coaxially connecting a large-diameter gear that meshes with the motor gear 78b and a small-diameter gear (not shown) that meshes with a guide gear 79 or a gear 91a described later. Further, the movement of the CIS module 76 is regulated by the guide gear 79 so that the moving direction of the CIS module 76 is the sub-scanning direction. That is, the CIS module 76 is configured to reciprocate in the sub-scanning direction along the guide gear 79 as the carriage motor 78 is driven.

  As shown in FIG. 1, the light source unit 71 includes three color light sources: a red LED 72R that turns on red light, a green LED 72G that turns on green light, and a blue LED 72B that turns on blue light. Is irradiated to the glass table 32 or the ADF reading area 34 through the light guide 73. The CIS 74 is configured such that a plurality of light receiving elements (CMOS image sensors) 75 for one line are arranged in the main scanning direction orthogonal to the sub scanning direction, and the lighting of the LEDs 72R, 72G, and 72B of the respective colors is sequentially switched. The color image data is generated by reading the reflected light one color at a time.

  The ADF unit 61 includes a pickup roller 63 disposed near the ADF insertion port 26, a feed roller 64 disposed adjacent to the pickup roller 63, a plurality of transport rollers 65 disposed in the transport path 62, and an ADF discharge unit. A paper discharge roller 66 disposed in the vicinity of the paper tray 28 is provided. The ADF unit 61 transports the document S placed on the ADF paper feed tray 27 in the transport direction by these rollers.

  In the conveyance path 62 (inside the opening 22a), the mark 22b is arranged toward the CIS 74 side (the lower surface side of the housing cover 22) so that the mark 22b can be read by the CIS 74. As shown in the enlarged view of FIG. 1, the mark 22b is formed as a black and white pattern in which rectangular regions painted in black are arranged on a white region and have different reflectivities in the main scanning direction. Further, the mark 22b is read based on switching of the output of the CIS 74 by the black and white pattern of the mark 22b by reading the area of the glass base 32 facing the mark 22b with the CIS 74 in a state where the housing cover 22 is closed. 22b can be detected.

  The main body side gear mechanism 90 is a mechanism that is disposed inside the flat bed portion 31 and transmits the driving force from the motor gear 78 a to the cover side gear mechanism 95. 5 is a cross-sectional view taken along line AA of FIG. 4, and FIG. 6 is a top view of an enlarged portion of FIG. As shown in FIGS. 5 and 6, the main body side gear mechanism 90 includes a gear 91a meshing with the motor gear 78c, a gear 91b meshing with the gear 91a, a gear 91c meshing with the gear 91b, and a gear 91d meshing with the gear 91c. I have. The main body side gear mechanism 90 includes a fixed tooth 91e disposed at a position slightly away from the gear 91d and a main body side connecting gear 92 that meshes with the gear 91c. The gear 91a is located at the left end of the guide gear 79 in the sub-scanning direction (the end on the ADF reading area 34 side of the glass table 32). That is, the gear 91a is located on the opposite side of the FB reading origin 35a in the sub-scanning direction, and the gear 91a and the FB reading origin 35a are separated from each other. The main body side coupling gear 92 is formed by coaxially connecting an external gear 92 a that meshes with the gear 91 c and an internal gear 92 b that meshes with the main body side gear mechanism 90 and transmits a driving force to the main body side gear mechanism 90. As shown in FIG. 4, the internal gear 92 b of the main body side coupling gear 92 is exposed from a hole 33 a formed in the upper surface of the frame 33 of the flat bed portion 31. When the housing cover 22 is closed, the internal gear 92 b meshes with the cover-side gear mechanism 95 so that the driving force can be transmitted to the cover-side gear mechanism 95.

  The cover side gear mechanism 95 is disposed inside the ADF unit 61 and transmits the driving force from the main body side gear mechanism 90 to the pickup roller 63, the feed roller 64, the transport roller 65, and the paper discharge roller 66 to rotate them. Mechanism. 7 and 8 are explanatory diagrams showing the internal structure of the ADF unit 61. FIG. 7 and 8 show a state in which the upper cover of the ADF unit 61 is removed from the housing cover 22. FIG. 9 is a B view of FIG. FIG. 10 is an enlarged view of the wavy frame C in FIG. As shown in FIG. 7, the cover side gear mechanism 95 includes a first gear group 96 and a second gear group 99.

  As shown in FIGS. 8 and 10, the first gear group 96 includes a cover side coupling gear 97 that meshes with the internal gear 92b of the main body side coupling gear 92, a gear 96a that meshes with the cover side coupling gear 97, and a gear 96a. A gear 96b meshing with the gear 96b, and a gear 96c meshing with the gear 96b. The first gear group 96 includes a gear 96d that meshes with the gear 96c and a gear 96e that meshes with the gear 96d. The first gear group 96 includes a gear 96f that meshes with the gear 96c, a gear 96g that meshes with the gear 96f, a gear 96h that meshes with the gear 96g, a gear 96i that meshes with the gear 96h, and a gear 96j that meshes with the gear 96i. (See FIG. 10). The cover side coupling gear 97 is formed by coaxially connecting an external gear 97a that meshes with the internal gear 92b of the main body side coupling gear 92 and a bevel gear 97b that meshes with the gear 96a. The external gear 97a is exposed on the lower surface of the housing cover 22 (see FIG. 1), and when the housing cover 22 is closed, the external gear 97a of the cover side connecting gear 97 is moved into the inner side of the main body side connecting gear 92. It is inserted into the gear 92b so that the two mesh with each other. The gears 96f to 96j are connected to the transport roller 65 and the paper discharge roller 66 via a coupling shaft and gears (not shown), and transmit the driving force to rotate them. The gear 96e is connected coaxially to the connecting shaft 98 (see FIG. 7), and transmits driving force to the second gear group 99 via the connecting shaft 98.

  As shown in FIG. 7, the second gear group 99 includes a gear 99a that is coaxially connected to the coupling shaft 98, a gear 99b that meshes with the gear 99a, a gear 99c that meshes with the gear 99b, and a gear 99d that meshes with the gear 99c. And a gear 99e meshing with the gear 99d. The second gear group 99 includes a gear 99f that is coaxially connected to the gear 99e, a gear 99g that meshes with the gear 99f, and a gear 99h that meshes with the gear 99g. The gear 99a is coaxially connected to the gear 96e via the connecting shaft 98, and rotates by the driving force from the gear 96e. The gear 99a is also coaxially connected to the feed roller 64 and transmits the driving force to the feed roller 64 to rotate. The gear 99h is connected coaxially to the pickup roller 63, and transmits driving force to the pickup roller 63 to rotate.

  The carriage motor 78 is configured as a stepping motor, and moves the CIS module 76 along the guide gear 79 in the sub-scanning direction. The carriage motor 78 transmits driving force to the main body side gear mechanism 90 and the cover side gear mechanism 95 to rotate the pickup roller 63, the feed roller 64, the transport roller 65, and the paper discharge roller 66.

  In the ADF reading operation mode, the scanner engine 60 first moves the CIS module 76 along the guide gear 79 to the ADF reading area 34 by the carriage motor 78. Then, the carriage motor 78 drives the main body side gear mechanism 90 and the cover side gear mechanism 95 to rotate each roller, thereby taking in the original S set in the ADF insertion port 26 one by one on the conveyance path 62. Automatically transport to. Then, the CIS module 76 reads the document S passing over the ADF reading area 34. In the FB reading operation mode, the scanner engine 60 first moves the CIS module 76 along the guide gear 79 to the right end in the sub-scanning direction in FIG. Then, using the FB reading origin 35a as the origin, the CIS module 76 itself reads the original S placed in the FB reading area 35 line by line while moving to the left in the sub-scanning direction. As described above, the carriage motor 78 is configured to serve as both a movement motor that moves the CIS module 76 in the sub-scanning direction and a conveyance motor that conveys the document S in the conveyance direction.

  As shown in FIG. 2, the scanner ASIC 50 includes a reading control unit 51, a drive control unit 52, a buffer 53, a reading time interval table storage unit 54, an LED driving unit 55, an A / D conversion unit 56, Is provided. The reading control unit 51 controls the reading of the document S by the CIS module 76 to acquire image data. The reading control unit 51 transmits a driving signal to the LED driving unit 55 or digital data (from the A / D conversion unit 56). Image data) or the image data is stored in the buffer 53. When the carriage motor 78 drives the main body side gear mechanism 90, the cover side gear mechanism 95, and the ADF unit 61 to convey the document S, the reading control unit 51 controls the CIS module 76 to convey the document being conveyed. It has a function of acquiring S by reading S. When the carriage motor 78 is temporarily stopped while the document S is being conveyed, the reading control unit 51 controls the CIS module 76 so that the reading time interval, which is a reading time interval related to acquisition of image data, is longer than that before the pause. It has a function of controlling and reading the original S to acquire image data and then stopping the acquisition of the image data. The reading control unit 51 controls the CIS module 76 so that when the carriage motor 78 pauses during conveyance of the document S, the reading time interval tends to become gradually longer than before the pause. It has a function of acquiring image data by reading. The reading control unit 51 has a function that, when the carriage motor 78 is temporarily stopped during the conveyance of the document S, the time until the acquisition of the image data is stopped becomes longer as the conveyance speed of the document S before the suspension is higher. Have The reading control unit 51 controls the CIS module 76 to read the original S when the carriage motor 78 resumes driving of the main body side gear mechanism 90 and the like after the carriage motor 78 is temporarily stopped during the conveyance of the original S. In acquiring the image data, the image data acquisition is resumed with a delay of the waiting time Tb from the start of the operation of the carriage motor 78. The drive control unit 52 transmits a control signal to the carriage motor 78 to control it. The drive control unit 52 has a function of driving the carriage motor 78 at a motor drive speed corresponding to the reading resolution. The buffer 53 temporarily stores image data read by the CIS module 76, and is composed of, for example, a FIFO. The LED driving unit 55 individually turns on and off the LEDs 72R, 72G, and 72B in accordance with the driving signal input from the reading control unit 51. The A / D converter 56 inputs analog data generated by the CIS 74 via an amplifier (not shown) and converts it into digital data.

  The reading time interval table storage unit 54 stores reading time interval tables 54a and 54b. FIG. 11 is an explanatory diagram of the reading time interval tables 54a and 54b. As shown in the figure, the reading time interval table storage units 54a and 54b include a resolution when reading the document S, a motor driving speed V that is a driving speed of the carriage motor 78, a reading time interval Ta during conveyance, and a carriage motor. 78 is associated with a reading time interval Tn at the time of primary stop 78 and a waiting time Tb when the operation of the carriage motor 78 resumes after the temporary stop. In the present embodiment, the scanner unit 40 is capable of reading at two resolutions of 1200 dpi and 600 dpi, and the reading time interval table 54a corresponds to 1200 dpi, and the reading time interval table 54b corresponds to 600 dpi. . In this embodiment, the scanner unit 40 keeps the reading time interval Ta during conveyance constant regardless of the resolution, and changes the conveyance speed of the document S, that is, the driving speed of the carriage motor 78 according to the resolution. Read. Therefore, a value A is associated with the reading time interval tables 54a and 54b as the reading time interval Ta. Further, the motor driving speed V is associated with the value Va in the reading time interval table 54a, and the value 2Va, which is a double value, is associated with the reading time interval table 54b because the resolution is ½. . That is, the motor driving speed V is set to be inversely proportional to the resolution. The reading time interval Tn is associated with five values from reading time intervals T1 to T5 in the reading time interval table 54a, and ten values from reading time intervals T1 to T10 in the reading time interval table 54b. A value is associated. The value of the reading time interval Tn is set as a ratio with respect to the reading time interval Ta, and is set so as to become gradually longer than the reading time interval Ta. Specifically, in the reading time interval table 54a, the reading time intervals T1, T2, T3, T4, and T5 are values Ta, Ta, Ta, 4Ta, and 8Ta, respectively. In the reading time interval table 54b, the values of the reading time intervals T1 to T5 are set to be the same as those of the reading time interval table 54a, and the values of the reading time intervals T6 to T10 tend to gradually increase from the value of the reading time interval T5. Is set to The waiting time Tb is set to be shorter as the resolution is higher, that is, as the motor driving speed V is higher. Specifically, in the reading time interval table 54a, the waiting time Tb is set to a value B, and in the reading time interval table 54b, since the motor driving speed V is double, the waiting time Tb is a value 0 that is a half value. .5B is set. That is, the waiting time Tb is set so as to be inversely proportional to the motor driving speed V (in other words, proportional to the resolution).

  The printer unit 42 includes a printer ASIC 44 and a printer engine 45. The printer ASIC 44 is an integrated circuit that controls the printer engine 45. Upon receiving a print command from the main controller 80, the printer ASIC 44 controls the printer engine 45 to print an image on recording paper based on an image file that is a target of the print command. . The printer engine 45 is configured as a well-known inkjet color printer mechanism that performs printing by ejecting ink from a print head onto paper. Since the printer unit 42 does not form the gist of the present invention, further detailed description is omitted.

  The operation panel 46 includes a display unit 47 disposed in the center and a power button 48 disposed on the left side of the display unit 47. The display unit 47 is configured as a touch panel type liquid crystal display, a mode button for selecting a mode, a selection / setting button for selecting a menu or an item by touching according to a guide displayed on the display, copying or printing Display a start button or the like to start the touch and accept a touch operation. Here, as modes that can be selected by the mode selection button, a copy mode for scanning and copying a document placed on the glass table 32 or an image stored in a memory card MC installed in the memory card slot 49 is used. There are a memory card mode in which a document is scanned and converted into data by scanning a document and stored in the memory card MC, and a film mode in which a photographic film is scanned and printed or data is stored in the memory card MC.

  The main controller 80 is configured as a microprocessor centered on the CPU 82, and includes a flash memory 84 that stores various processing programs, various data, various tables, and a RAM 86 that temporarily stores scan data and print data. And an interface (I / F) 88 that enables communication with the operation panel 46. The main controller 80 inputs various operation signals and various detection signals from the printer unit 42 and the scanner unit 40, and inputs operation signals generated in response to a touch operation on the operation panel 46. In addition, an image file is read from the memory card MC, a command is output to the printer unit 42 to execute printing of image data, and a document placed on the glass table 32 is read based on a scan command from the operation panel 46. A command is output to the scanner unit 40 to read as image data, or a control command for the display unit 47 is output to the operation panel 46.

  Next, the operation of the scanner unit 40 of the present embodiment configured as described above, particularly the operation when scanning in the ADF reading mode will be described. FIG. 12 is a flowchart illustrating an example of an ADF image reading processing routine executed by the scanner ASIC 50. For example, when the user sets the document S in the ADF insertion slot 26 and performs an operation of pressing a start button (not shown) displayed on the operation panel 46, the main controller 80 scans the scanner so as to perform scanning in the ADF reading operation mode. A command is output to the unit 40. The ADF image reading processing routine is executed when the scanner ASIC 50 receives this command. The scanner ASIC 50 executes an ADF image reading processing routine by using functions such as the reading control unit 51 and the drive control unit 52.

  When this routine is executed, the scanner ASIC 50 first moves the CIS module 76 to a position facing the ADF reading area 34 (step S100). This is done by outputting a driving force from the carriage motor 78 so that the motor gear 78c rotates counterclockwise in FIG. 6 and moving the CIS module 76 in the left direction in FIG. As a result, the CIS module 76 faces the ADF reading area 34, the motor gear 78 c is separated from the end of the guide gear 79, and the motor gear 78 c is engaged with the gear 91 a instead of the guide gear 79.

  Subsequently, the scanner ASIC 50 acquires the reading resolution (step S110). This is performed, for example, by the user inputting the reading resolution used for the current reading by touching the operation panel 46 and acquiring the input reading resolution via the main controller 80. For example, the reading resolution transmitted by an external device such as a PC (personal computer) connected to the multifunction printer 20 may be acquired. Then, the scanner ASIC 50 reads the motor driving speed V corresponding to the reading resolution from the reading time interval table storage unit, and drives the carriage motor 78 at the read motor driving speed V (step S120). For example, when the reading resolution is 1200 dpi, the carriage motor 78 is driven at the value Va of the motor driving speed V read from the reading time interval table 54a. The rotation direction of the carriage motor 78 is the same as that in step S100. Thereby, the driving force from the carriage motor 78 is transmitted to the motor gears 78a to 78c, the gears 91a to 91c, and the main body side connecting gear 92 in this order. Then, the driving force is transmitted from the main body side connecting gear 92 to the cover side gear mechanism 95, and the pickup roller 63, the feed roller 64, the transport roller 65, and the paper discharge roller 66 start to rotate. Therefore, the document S inserted into the ADF insertion port 26 is conveyed along the conveyance path 62 by each roller. At this time, since the fixed teeth 91e of the main body side gear mechanism 90 do not mesh with the gear 91d, the fixed teeth 91e do not hinder the rotational driving of the gears 91a to 91c and the main body side connecting gear 92.

  Next, the scanner ASIC 50 determines whether or not the leading edge of the document S has been detected (step S130). This process is performed as follows, for example. First, the CIS module 76 determines whether or not the color of the ADF reading area 34 has changed to a predetermined threshold value or more (= whether or not the color difference of the ADF reading area 34 has become a predetermined value or more) compared to before the start of conveyance of the document S. Find out by. When the change is detected, it is determined that the document S has reached the ADF reading area 34, that is, the leading edge of the document S has been detected. If the leading edge of the document S is not detected in step S130, the process of step S130 is repeated until it is detected.

  When the leading edge of the document S is detected in step S130, a reading process for the document S is executed (step S140). Specifically, the LED drive unit 55 causes the light source unit 71 to emit light while sequentially turning on the LEDs 72R, 72G, and 72B of the respective colors, and causes the CIS module 76 to read the document S. Then, the image data read via the A / D converter 56 is acquired and stored in the buffer 53.

  Subsequently, the scanner ASIC 50 checks whether or not the buffer free space shortage flag F is 1 (S150). The buffer free space shortage flag F is set to a value of 1 when the free space of the buffer 53 is less than a predetermined capacity threshold, and is set to a value of 0 when the free space is above a predetermined threshold. The predetermined capacity threshold is determined as a capacity for storing image data acquired by reading the document S when a carriage motor 78, which will be described later, is temporarily stopped, and a capacity with a margin added thereto. Note that the capacity threshold may be variable according to the reading resolution acquired in step S100.

  If the buffer free space shortage flag F is 0 in step S150, it is determined whether the trailing edge of the document S has been detected (step S160). This process is performed, for example, by detecting a change in the color of the ADF reading area 34 by the CIS module 76, as in the case of detecting the leading edge of the document S in step S130. If the trailing edge of the document S is not detected, it is determined whether or not the reading time interval Ta has elapsed since the immediately preceding document S reading process (step S170). Note that the value of the reading time interval Ta is used by reading a value corresponding to the reading resolution from the table stored in the reading time interval table storage unit 54. If the reading time interval Ta has not elapsed, the process proceeds to step S160, and the processing of steps S160 and S170 is repeated until the trailing edge of the document is detected in step S160 or until the reading time interval Ta has elapsed in step S170. .

  When the reading time interval Ta elapses in step S170, the processing after step S140 is performed. Thus, the reading process of the document S is performed in step S140 when the reading time interval Ta has elapsed from the reading process of the immediately preceding document S. In addition, while the buffer free space flag is 0 in step S150 and the trailing edge of the document S is not detected in step S160, the reading process of the document S is repeatedly performed at every reading time interval Ta. Thus, the document S is read at every reading time interval Ta while the document S is being conveyed, and the image data obtained by reading the document S at the reading resolution is sequentially stored in the buffer 53. Steps S140 to S170 are also referred to as normal processing.

  When the trailing edge of the document S is detected in step S160, it is detected whether the next document S is in the ADF paper feed tray 27 (step S180). This processing is performed based on whether or not the document S is detected by a document detection sensor (not shown) provided at the ADF insertion port 26, for example. Then, when there is a next document S, the processing after step S130 is performed. When there is no next original S, this routine is terminated.

  Here, the main controller 80 sequentially reads image data from the buffer 53 and stores it in the RAM 86 in parallel with the ADF image reading processing routine. When all the image data of one document S is prepared, the process of storing them together as one image file, for example, in the memory card MC is sequentially performed. Therefore, if the speed at which the main controller 80 reads the image data from the buffer 53 is higher than the speed at which the scanner ASIC 50 stores the image data in the buffer 53, the buffer 53 has a sufficient free space and the buffer free space flag has a value of 0. Will remain. In such a case, the normal process is repeated until the trailing edge of the document S is detected. However, if the speed at which the image data is stored is higher than the speed at which the image data is read from the buffer 53 for some reason, such as when the main controller 80 performs other processing in parallel, the buffer 53 gradually. The free space of will decrease. When the free capacity of the buffer 53 becomes less than the capacity threshold, the buffer free capacity flag becomes 1. Hereinafter, such a case will be described.

  When the buffer free space flag is 1 in step S150, the scanner ASIC 50 stops the drive signal to the carriage motor 78 and temporarily stops the carriage motor 78 (step S190). Subsequently, the scanner ASIC 50 sets the variable n as an initial value 1 (step S200), and checks whether or not the reading time interval Tn exists in the reading time interval table corresponding to the reading resolution (step S210). For example, when the variable n is 1 and the reading resolution is 1200 dpi, it is checked whether or not the reading time interval T1 exists in the reading time interval table 54a. When the reading time interval Tn exists, the process waits until the reading time interval Tn has elapsed from the reading processing of the immediately preceding document S (step S220), and when the reading time interval Tn has elapsed, the reading processing of the document S is executed. (Step S230). For example, when the variable n is the value 1 and the reading resolution is 1200 dpi, the reading time interval T1 of the reading time interval table 54a is set to the same value as the reading time interval Ta. The reading process of the document S is executed when the reading time interval Ta elapses.

  When the reading process of the document S is executed, the variable n is incremented by 1 (step S240), and the processes after step S210 are executed. Thus, S210 to S240 are repeated until the reading time interval Tn does not exist in step S210, and the reading process of the document S is performed every time the reading time interval Tn of the reading time interval table elapses. For example, when the reading resolution is 1200 dpi, the original S is first read to acquire image data when the reading time interval T1 (= Ta) has elapsed, and then the original S is read to obtain an image when the reading time interval T2 (= Ta) has elapsed. Similarly, after that, when the reading time interval T3 (= Ta) has passed, the reading time interval T4 (= 4Ta) has passed, and the reading time interval T5 (= 8Ta) has passed, the original S is read to obtain image data. get. When the variable n reaches the value 6, since the reading time interval T6 does not exist in the reading time interval table 54a, it is determined in the next step S210 that the reading time interval Tn does not exist.

  If it is determined in step S210 that the reading time interval Tn does not exist, the process waits until the buffer free space flag F becomes 0 (step S250). As a result, the storage of the image data in the buffer 53 is temporarily stopped, so that it is possible to avoid a situation in which the image data cannot be stored due to insufficient free space in the buffer 53. Steps S210 to S250 are also referred to as a temporary stop process. Then, the main controller 80 reads the image data from the buffer 53, and when the buffer free space flag F becomes 0 in step S250, the scanner ASIC 50 starts outputting a drive signal to the carriage motor 78 and drives the carriage motor 78. It resumes (step S260). When the driving is resumed, the carriage motor 78 is driven at the motor driving speed V corresponding to the reading resolution as in step S110.

  When the driving of the carriage motor 78 is resumed, the scanner ASIC 50 performs a restart process that waits until the waiting time Tb elapses (step S270). When the waiting time Tb elapses, the process after step S140, that is, the normal time process is executed. That is, when the waiting time Tb elapses, the document S is read in step S140, and while the buffer free space shortage flag F is 0 in step S150, the reading time until the trailing edge of the document S is detected in step S160. The document S is read at each interval Ta. When the trailing edge of the document S is detected, the next document S is similarly read at each reading time interval Ta, and when there is no next document, this routine is terminated.

  As described above, in the ADF reading processing routine of the present embodiment, when the carriage S 78 is driven and the document S is conveyed, the document S is read at every reading time interval Ta stored in the reading time interval table storage unit 54. A normal process for performing a reading process is performed. On the other hand, when the carriage motor 78 is temporarily stopped, the reading process of the document S is performed at every reading time interval Tn stored in the reading time interval table storage unit 54, and then the temporary stop process for stopping the reading process is performed. FIG. 13 is an explanatory diagram showing a state in which normal processing and temporary suspension processing are performed. As shown in the figure, the scanner unit 40 performs a process of acquiring image data by reading each color of R, G, and B in the document S once, as a single reading process. For example, Nos. A to c in FIG. 13 are one reading process. In the normal process, the document S is read at every reading time interval Ta. Therefore, for example, no. When the reading time interval Ta has elapsed from the reading of the R color of a, Read the R color of d. In this way, no. ac, No. df, No. After performing the reading process of g to i three times, the buffer free space shortage flag F becomes 1, and at time t1, the drive signal to the carriage motor 78 is stopped in step S190 to temporarily stop the carriage motor 78. Suppose. Then, the scanner ASIC 50 performs a temporary stop process after time t1. Therefore, for example, when the reading resolution is 1200 dpi, the reading time interval table 54a is first checked as described above, and the document S is read when the reading time interval T1 (= Ta) has elapsed from the immediately preceding reading process to obtain image data. For example, for the R color, the next reading of the R color (No. 0) is performed when the reading time interval T1 has elapsed since the reading of the R color in the immediately preceding reading process (No. g). Similarly, for the G and B colors, the next G color is read (No. 1) when the reading time interval T1 elapses from the reading of the G color in the immediately preceding reading process (No. h), and the immediately preceding reading process (No. .I) When the reading time interval T1 has elapsed from the reading of B color, the next reading of B color (No. 2) is performed. Thereafter, similarly, the reading process is sequentially performed according to the reading time interval Tn of the reading time interval table 54a. In the reading time interval table 54a, since the reading time intervals T1 to T3 are set to the value Ta, the three reading processes (Nos. 0 to 8) after time t1 are the same as the normal time process. Done every time. Subsequently, since the reading time interval T4 is set to the value 4Ta, when the reading time interval T4 (= 4Ta) elapses from the third reading processing (No. 6-8), the fourth reading processing (No. 18- 20) is performed. That is, as compared with the case where the reading process is performed at the same reading time interval Ta as in the normal process, No. The reading processing for three times 9 to 11, 12 to 14, and 15 to 17 is not performed. In FIG. 13, if there is no “◯” in the “read” column, it means that the reading process is not performed. Since the reading time interval T5 is set to the value 8Ta, the fifth reading process (Nos. 42 to 44) is performed when the reading time interval T5 (= 8Ta) elapses from the fourth reading process (Nos. 18 to 20). ) Is performed. That is, as compared with the case where the reading process is performed at the same reading time interval Ta as in the normal process, No. The seven reading processes 21 to 23, 24 to 26, 27 to 29, 30 to 32, 33 to 35, 36 to 38, and 39 to 41 are not performed. Since the reading time interval T6 does not exist in the reading time interval table 54a, the reading process in the temporary stop process is not performed after the time t2 when the fifth reading process is completed. As described above, in the suspension process, the reading process is performed so that the reading time interval becomes longer and gradually longer than that in the normal process, and then the reading process is stopped.

  Here, the reason why the reading time interval Tn is set to have a tendency that the reading time interval becomes longer and gradually longer than before the temporary stop will be described. Since each roller such as the transport roller 65 receives a driving force from the carriage motor 78 via the main body side gear mechanism 90, the cover side gear mechanism 95, and the motor gears 78a to 78c, even if the carriage motor 78 is temporarily stopped. Each roller does not stop immediately but continues to rotate, decelerates and stops. Therefore, even after the carriage motor 78 is temporarily stopped (after time t1 in FIG. 13), the document S is conveyed while being decelerated and then stops. In the pause processing of the multi-function printer 20 of the present embodiment, the reading process of the document S is performed while the reading time interval tends to be gradually increased according to the behavior of the document S when the carriage motor 78 is temporarily stopped. Is done. Therefore, it is possible to acquire image data obtained by reading the document S with high accuracy when the conveyance of the document S is stopped. Note that the value of the reading time interval Tn in the reading time interval tables 54a and 54b is the same as that of the original S when the original S is being transported by the carriage motor 78 even when the original S is stopped while decelerating. It is set to be able to perform the reading process. In other words, the value of the reading time interval Tn is such that the conveyance distance between the lines to be read by the CIS module 76 is during the conveyance of the document S by the carriage motor 78 (during normal processing) and during the pause (processing during the pause). ) And are set to be the same. Such a value of the reading time interval Tn can be determined by experiment, for example.

  In the reading time interval table 54a, the reading time interval Tn is set from T1 to T5, and the total time is a value 15Ta (= Ta + Ta + Ta + 4Ta + 8Ta). On the other hand, since the reading time interval Tn is set from T1 to T10 in the reading time interval table 54b, the total time of the reading time intervals Tn is longer than that of the reading time interval table 54a. Here, the faster the conveyance speed of the document S before the carriage motor 78 is temporarily stopped, the longer the time until the document S stops at the time of the temporary stop. For this reason, the lower the resolution is, that is, the faster the conveyance speed of the document S before the carriage motor 78 is temporarily stopped (during normal processing), the longer the time until the reading process of the document S in the suspension processing is stopped. Therefore, the image data obtained by reading the document S with high accuracy can be acquired in accordance with the behavior of the document S during the pause. Note that the total value of the reading time intervals Tn can also be determined by experiments, for example.

  As described above, in the multi-function printer 20 of the present embodiment, the reading time interval Tn for performing the reading process of the document S when the carriage motor 78 is temporarily stopped matches the behavior of the document S, so that the document S can be accurately obtained. The image data obtained by reading is acquired. That is, it is possible to prevent the image based on the image data obtained by reading the document S from being extended or missing.

  In the multi-function printer 20 of the present embodiment, when the carriage motor 78 is resumed after the carriage motor 78 is temporarily stopped while the document S is being conveyed, the image is delayed by a waiting time Tb from the start of the operation of the carriage motor 78. Performs restart processing to resume data acquisition. FIG. 14 is an explanatory diagram illustrating a state in which the restart process and the subsequent normal process are performed. FIG. 14 shows a case where the resolution is 1200 dpi and the waiting time Tb (= value B) is the value 6Ta. As shown in the figure, it is assumed that the buffer free space shortage flag F becomes 0, and at time t3, output of a drive signal to the carriage motor 78 is started in step S260 and driving of the carriage motor 78 is resumed. Then, the scanner ASIC 50 performs restart processing after time t3. Specifically, as the restart process, the process waits until time t4 when the waiting time Tb has elapsed from time t3, and proceeds to step S140 to start the normal process. That is, as compared with the case where the reading process is started immediately when the driving of the carriage motor 78 is resumed, No. 6 corresponding to the seventh time is not performed without performing six reading processes of 0 to 2, 3 to 5, 6 to 8, 9 to 11, 12 to 14, and 15 to 17. The reading processes 18 to 20 are started at time t4 when the waiting time Tb (= 6Ta) has elapsed, and the normal process is performed thereafter. In this way, the normal processing is resumed with a delay of the waiting time Tb from the resumption of the driving of the carriage motor 78, and the reading processing is performed. Here, each roller such as the transport roller 65 receives a driving force from the carriage motor 78 via the main body side gear mechanism 90, the cover side gear mechanism 95, and the motor gears 78a to 78c. Therefore, when driving of the carriage motor 78 is resumed, there is a time difference until the power from the carriage motor 78 is transmitted from each roller to the document S. Therefore, by restarting the reading process of the document S after the waiting time Tb elapses, the reading process of the document S is performed between the time when the driving of the carriage motor 78 is restarted and the time when the conveyance of the document S is started, and the image is extended. Is suppressed. Note that the waiting time Tb can be determined by experiment so as to be the same as the time difference until the conveyance of the document S is started when the carriage motor 78 is resumed. In addition, the lower the reading resolution, that is, the higher the driving speed of the carriage motor 78 when driving is resumed, the smaller the time difference until the conveyance of the document S starts. Therefore, in this embodiment, the waiting time Tb is determined so that the waiting time Tb becomes smaller as the reading resolution is lower, so that the image data obtained by reading the document S can be acquired more accurately when driving is resumed.

  When the reading process is performed in the FB reading operation mode after the end of the ADF image reading process routine described above, the scanner ASIC 50 first drives the driving force from the carriage motor 78 so that the motor gear 78c rotates clockwise in FIG. Is output. As a result, the gear 91c rotates counterclockwise in FIG. Then, the gear 91d moves in the lower left direction in FIG. 6 and meshes with the fixed tooth 91e, and the gear 91d is fixed and does not rotate. As a result, the gear 91a is also fixed and does not rotate, and since the motor gear 78c is rotating clockwise, it moves to the right in FIG. 6 and moves away from the gear 91a and meshes with the guide gear 79 instead. By engaging with the guide gear 79, the CIS module 76 can be moved in the sub-scanning direction by the carriage motor 78. Thereby, the ADF reading operation mode can be shifted to the FB reading operation mode.

  Here, the correspondence between the components of the present embodiment and the components of the present invention will be clarified. The ADF unit 61, the main body side gear mechanism 90, and the cover side gear mechanism 95 of this embodiment correspond to the document conveying means of the present invention, the carriage motor 78 corresponds to the driving means, the CIS module 76 corresponds to the reading means, A scanner ASIC 50 including a reading control unit 51, an LED driving unit 55, and an A / D conversion unit 56 corresponds to a reading control unit. The FB reading area 35 corresponds to the document placement area.

  According to the multifunction printer 20 of the present embodiment described in detail above, when the carriage motor 78 drives the main body side gear mechanism 90, the cover side gear mechanism 95, and the ADF unit 61 to convey the document S, the CIS module. The normal process of acquiring image data by reading the document S being conveyed by controlling 76 is performed. When the carriage motor 78 is temporarily stopped while the document S is being conveyed, the reading time interval Tn, which is a reading time interval related to acquisition of image data, is compared with the reading time interval Ta before the temporary stop (= normal time processing). Then, the CIS module 76 is controlled so that the original S is read to acquire the image data, and thereafter, a temporary stop process for stopping the acquisition of the image data is performed. Accordingly, when the main body side gear mechanism 90, the cover side gear mechanism 95, and the ADF unit 61 are decelerated and stopped immediately when the carriage motor 78 is temporarily stopped, the image data obtained by reading the document S can be obtained with high accuracy. .

  Further, when the carriage motor 78 is temporarily stopped while the document S is being conveyed, the document is controlled by controlling the CIS module 76 so that the reading time interval Tn tends to be gradually longer than the reading time interval Ta before the suspension. S is read to obtain image data. Therefore, when the carriage motor 78 is temporarily stopped, the main body side gear mechanism 90, the cover side gear mechanism 95, and the ADF unit 61 do not stop immediately but stop while gradually decelerating. it can.

  Further, when the carriage motor 78 is temporarily stopped during the conveyance of the document S, the time until the acquisition of the image data is stopped tends to be longer as the conveyance speed of the document S before the suspension is higher. Therefore, it is possible to acquire image data obtained by reading a document with higher accuracy in accordance with the behavior of document transportation during a pause.

  Furthermore, the main body side gear mechanism 90 and the cover side gear mechanism 95 transmit the power from the carriage motor 78 to the document S via a gear train composed of a plurality of gears. For this reason, when the carriage motor 78 is temporarily stopped, the document S is not immediately stopped but is likely to be decelerated and stopped, and the significance of applying the present invention is high.

  The carriage motor 78 also serves as means for driving the main body side gear mechanism 90, the cover side gear mechanism 95, and the ADF unit 61, and means for moving the CIS module 76 in the movement direction (sub-scanning direction). The CIS module 76 reads the original while the CIS module 76 moves in the moving direction by the carriage motor 78 in the FB reading operation mode in which the original placed on the FB reading area 35 is read. As described above, when the carriage motor 78 serves as the role of transporting the document S in the ADF reading operation mode and the role of moving the CIS module 76 in the FB reading operation mode, the main body side gear mechanism 90 and the cover side gear mechanism 95 are used. The position of the document S is easily separated from the carriage motor 78, for example, the document S is transported through a long wheel train composed of a plurality of gears. For this reason, when the carriage motor 78 is temporarily stopped, the document S is not immediately stopped but is likely to be decelerated and stopped, and the significance of applying the present invention is high.

  Further, when the carriage motor 78 resumes driving of the main body side gear mechanism 90, the cover side gear mechanism 95, and the ADF unit 61 after the carriage motor 78 is temporarily stopped during the conveyance of the document S, the CIS module 76 is controlled. When the image data is acquired by reading the document S, a restart process is performed in which the acquisition of the image data is resumed with a delay of the waiting time Tb from the start of the operation of the carriage motor 78. Therefore, even when the carriage motor 78 starts operating, the conveyance of the document S is not started immediately, and the image data obtained by reading the document S can be obtained with high accuracy.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  For example, in the above-described embodiment, the multi-function printer 20 supports two reading resolutions of 1200 dpi and 600 dpi, and the reading time interval table storage unit 54 has two tables of reading time interval tables 54a and 54b corresponding to the reading resolution. Although it is assumed that it is remembered, it is not limited to this. For example, three or more reading resolutions may be supported, and a reading time interval table may be stored according to each resolution. Further, a reading time interval table corresponding to the conveyance speed of the document S instead of the resolution may be stored, or a reading time interval table corresponding to the driving speed of the carriage motor 78 may be stored. Good. That is, it is only necessary to store different reading time interval tables that are directly or indirectly associated with the conveyance speed of the document S. Alternatively, the same reading time interval table may be used regardless of the resolution, the conveyance speed of the document S, and the like. Different reading time interval tables may be stored according to the type of document S such as material and size. In this case, a sensor for detecting the type of the document S may be provided in the ADF insertion port 26, or the type of the document S may be input from the user via the operation panel 46.

  In the above-described embodiment, the reading time interval T1 to T5 is a common value in the reading time interval table storage unit 54a and the reading time interval table storage unit 54b. . For example, the tendency of the reading time interval Tn may be changed according to the conveyance speed and reading resolution of the document S before being paused by the carriage motor 78. For example, when the conveyance speed of the document S is slower, the reading time interval Tn tends to be longer than when the conveyance speed of the document S before the pause is faster, or when the reading time interval Tn is gradually increased. The change in the reading time interval Tn may be made steep.

  In the above-described embodiment, when the driving of the carriage motor 78 is resumed in step S260, the reading process of the document S is resumed after the waiting time Tb corresponding to the reading resolution has elapsed. For example, the reading process of the document S may be resumed after the waiting time Tb has passed according to the conveyance speed of the document S and the driving speed of the carriage motor 78 instead of the reading resolution. The same waiting time Tb value may be used regardless of the reading resolution and the conveyance speed of the document S, or the reading process of the document S may be resumed without waiting for the waiting time Tb to elapse. Alternatively, the waiting time Tb may be changed according to the type of the document S.

  In the embodiment described above, the waiting time Tb is determined to be the same time as the time difference until the conveyance of the document S is started when the carriage motor 78 is restarted, but is not limited thereto. For example, the transport distance of the document S from the last reading process in the pause process to the first read process after the restart process is the transport distance of the document S during the normal process. The waiting time Tb may be set so as to be the same (= the resolution is the same). For example, the transport distance until the document S stops after the last reading process in the pause processing is defined as a distance X, and the transport distance (distance between the reading lines) of the document S during the reading processing in the normal processing is a distance. Y. At this time, a waiting time is added to the time difference between the restart of driving of the carriage motor 78 and the start of conveyance of the document S, plus the time required for the document S to move by the distance (Y−X). It may be determined as time Tb. The distance X can be obtained by experiment, for example.

  In the above-described embodiment, the carriage motor 78 serves as both a movement motor that moves the CIS module 76 in the sub-scanning direction and a conveyance motor that conveys the document S in the conveyance direction. Not limited. For example, the carriage motor 78 may be used only as a conveyance motor, and may include a separate movement motor.

  In the above-described embodiment, the conveyance direction and the sub-scanning direction are the same direction. However, the present invention is not limited to this and may be different directions.

  In the embodiment described above, the carriage motor 78 is a stepping motor, but is not limited thereto. For example, the carriage motor 78 may be a DC motor. In this case, the position of the carriage motor 78 and the CIS module 76 in the sub-scanning direction may be detected by an encoder. The carriage motor 78 is temporarily stopped when the drive signal from the drive control unit 52 is stopped. However, the carriage motor 78 is not limited thereto, and may be temporarily stopped when a stop signal is input.

  In the above-described embodiment, the main body side gear mechanism 90 and the cover side gear mechanism 95 use the main body side gear mechanism 90 and the cover side gear mechanism 95 having a gear train composed of a plurality of gears to transmit power from the carriage motor 78 to the original. However, the present invention is not limited to this. For example, the carriage motor 78 and each roller such as the transport roller 65 may be connected via a single gear. Further, the driving force from the carriage motor 78 may be transmitted to the document S by a mechanism other than the gear.

  In the above-described embodiment, the total time of the reading time interval Tn, that is, the time until the acquisition of image data is stopped when the carriage motor 78 is temporarily stopped is longer as the reading resolution is lower, but is not limited thereto. . The total time of the reading time interval Tn may be increased as the conveyance speed of the document S and the driving speed of the carriage motor 78 are increased, or the total of the reading time intervals Tn regardless of the reading resolution and the conveyance speed of the document S. The time may be the same. Alternatively, the total time of the reading time interval Tn may be changed according to the type of document S.

  In the above-described embodiment, when the carriage motor 78 is temporarily stopped, the reading process of the document S is repeated until the reading time interval Tn does not exist. However, the present invention is not limited to this. For example, the time until the reading process of the document S is stopped when the carriage motor 78 is temporarily stopped may be set separately.

  In the above-described embodiment, the reading time intervals T1 to T3 are the same as the reading time interval Ta, that is, the same as the reading time interval before the carriage motor 78 is temporarily stopped. The reading time interval Tn only needs to be gradually longer than the reading time interval Ta before the temporary stop. For example, the reading time intervals T1 to T3 may be larger than the reading time interval Ta, or the reading time intervals T1 to T3 may be different values. The reading time interval Tn may be lengthened in a linear function, may be lengthened in a quadratic function, or may be lengthened in a step function. Further, the reading time interval Tn is not limited to the tendency to become longer gradually than the reading time interval Ta, and may simply be a value longer than the reading time interval Ta. For example, all the reading time intervals T1 to T5 in the reading time interval table 54a may be 2Ta. Further, only one reading time interval Tn may be set. In that case, the reading time interval T1 may be longer than the reading time interval Ta.

  In the embodiment described above, the reading time interval Tn is stored in the reading time interval table as a ratio to the reading time interval Ta, but is not limited thereto. For example, the reading time interval Tn may be stored as an absolute value.

  In the embodiment described above, the carriage motor 78 is temporarily stopped when the free capacity of the buffer 53 is less than the predetermined capacity threshold, but the present invention is not limited to this. For example, the carriage motor 78 may be temporarily stopped when the buffer 53 becomes full. In this case, the image data acquired by the reading process of the document S after the carriage motor 78 is temporarily stopped may be stored in a predetermined storage area other than the buffer 53. Further, the carriage motor 78 may be temporarily stopped when the carriage motor 78 fails or is abnormal (overheating or the like). Further, the buffer 53 is provided in the scanner ASIC 50, but is not limited thereto, and the buffer 53 may be provided in the RAM 86 of the main controller 80.

  In the above-described embodiment, the value of the buffer free capacity flag F is determined depending on whether or not the free capacity of the buffer 53 is less than a predetermined capacity threshold, but is not limited thereto. For example, the capacity threshold value may be changed depending on whether the buffer free capacity flag F changes from the value 0 to the value 1 or from the value 1 to the value 0. That is, the change in the value of the buffer free capacity flag F may be provided with hysteresis.

  In the above-described embodiment, the motor driving speed V is changed according to the reading resolution, and the reading time interval Ta is the same regardless of the reading resolution, but is not limited thereto. For example, the reading time interval Ta is changed according to the reading resolution, and the motor driving speed V may be the same regardless of the reading resolution. Further, both the motor driving speed V and the reading time interval Ta may be changed according to the reading resolution.

  In the above-described embodiment, the CIS module 76 reads the document S every reading time interval Tn when the carriage motor 78 is temporarily stopped. However, the present invention is not limited to this. When the carriage motor 78 is temporarily stopped while the document S is being transported, it suffices if the reading time interval, which is the reading time interval for acquiring image data, is longer than that before the pause. For example, the CIS module 76 may read the document S at every reading time interval Ta even when the carriage motor 78 is temporarily stopped. In this case, a part of the read image data is ignored by the reading control unit 51 (not stored in the buffer 53), and as a result, image data obtained by reading the document S at every reading time interval Tn is acquired. do it. For example, when the reading time interval T1 is 3Ta, the CIS module 76 performs reading at every reading time interval Ta, and the reading control unit 51 reads the first two image data read by the CIS module 76. May be ignored, and only the third image data may be stored in the buffer 53. That is, for example, even during the pause processing in FIG. 13, the reading by the CIS module 76 is performed at the same reading time interval Ta as in the normal processing, and the timing when there is no reading “◯” (No. 9 to 17, No. 21-41), the read image data may be ignored. Note that it is possible to ignore a part of the image data at any stage. For example, part of the image data as analog data from the CIS module 76 may be ignored by not inputting it to the A / D converter 56. Alternatively, all the image data from the CIS module 76 may be stored in the buffer 53, and a part of the image data read from the buffer 53 on the main controller 80 side may be ignored. In this case, the scanner ASIC 50 and the main controller 80 correspond to the reading control means of the image reading apparatus of the present invention. Similarly, it is only necessary to stop the acquisition of image data while waiting for the buffer free space shortage flag F to become 0 in step S250. For example, during the restart processing (Nos. 0 to 17) in FIG. 14, the reading of the document S by the CIS module 76 is performed at the same reading time interval Ta as the normal processing, and the image data from the CIS module 76 is read. It is good also as what ignores all.

  In the above-described embodiment, the multifunction printer 20 has been described. However, a scanner device that does not include the printer unit 42 may be used, or a FAX device that includes a FAX function may be used. In addition, the printer unit 42 is an inkjet color printer mechanism, but is not particularly limited thereto, and may be an electrophotographic color printer, a dot impact color printer, or a monochrome printer of these. It is good.

  In the above-described embodiment, the multifunction printer 20 has been described. However, a control method for the image reading apparatus may be used, or a program for executing this method may be used.

  20 Multifunction Printer, 21 Case, 22 Case Cover, 22a Opening, 22b Mark, 22c Document Press, 24 Paper Discharge Tray, 26 ADF Insertion Port, 27 ADF Paper Feed Tray, 28 ADF Paper Output Tray, 29 Document Guide , 31 Flatbed section, 32 Glass stand, 33 frame, 33a hole, 34 ADF scanning area, 35 FB scanning area, 35a FB scanning origin, 36 White reference plate, 40 Scanner unit, 42 Printer unit, 44 Printer ASIC, 45 Printer Engine, 46 Operation panel, 47 Display unit, 48 Power button, 49 Memory card slot, 50 Scanner ASIC, 51 Reading control unit, 52 Drive control unit, 53 Buffer, 54 Reading time interval table storage unit, 54a, 54b Time interval table, 55 LED drive unit, 56 A / D conversion unit, 60 scanner engine, 61 auto document feeder (ADF) unit, 62 transport path, 63 pickup roller, 64 feed roller, 65 transport roller, 66 paper discharge roller, 71 Light source unit, 72R, 72G, 72B LED, 73 light guide, 74 CIS, 75 light receiving element, 76 CIS module, 78 carriage motor, 78a, 78b, 78c motor gear, 79 guide gear, 80 main controller, 82 CPU, 84 Flash memory, 86 RAM, 88 Interface (I / F), 90 Main body side gear mechanism, 91a to 91d gear, 91e Fixed tooth, 92 Main body side connecting gear, 92a External gear, 92b Internal gear, 95 Cover side gear mechanism, 96 first gear group, 96a to 96j gear, 97 cover side connecting gear, 97a external gear, 97b bevel gear, 98 connecting shaft, 99 second gear group, 99a to 99h gear, MC memory card, S Manuscript.

Claims (7)

A housing body;
A housing cover attached to the housing body so as to be openable and closable ;
A document setting means disposed on the housing cover for setting a document;
A document conveying means disposed in the casing cover and configured to convey a document set on the document setting means in a conveying direction;
A document placement table disposed on the upper surface of the housing body and having a document placement area;
Reading means for reading the original conveyed by the original conveying means and the original placed on the original placement area ;
A driving unit disposed in the housing body and configured to move the reading unit in a moving direction;
A driving force transmitting means for transmitting a driving force of the driving means to the document conveying means; and a first connecting means disposed on the housing main body and a second connecting means disposed on the housing cover. When,
When the driving unit drives the document conveying unit to convey the document, the reading unit is controlled to read the document being conveyed to acquire image data. When the driving unit pauses, the reading unit is controlled so that the reading time interval, which is the reading time interval related to acquisition of image data, tends to be gradually longer than before the pause. Reading control means for acquiring image data by reading, and then stopping acquisition of the image data;
With
The reading means reads the original while moving in the moving direction by the driving means when reading the original placed on the original placement area;
The document table is covered with the housing cover when the housing cover is closed,
The first connecting means and the second connecting means are disconnected when the housing cover is opened, and are connected to each other when the housing cover is closed.
Image reading device. The driving force transmitting means transmits the driving force of the driving means to the document conveying means via the connected first connecting means and second connecting means;
The image reading apparatus according to claim 1. When the driving unit pauses during conveyance of the document, the reading control unit tends to have a longer time until the acquisition of the image data is stopped as the document conveyance speed before the suspension is higher. To
The image reading apparatus according to claim 1. The reading control unit changes a tendency of the reading time interval according to a conveyance speed of the document before the suspension when the driving unit pauses during conveyance of the document.
The image reading apparatus according to claim 1. The reading control unit may change the tendency of the reading time interval according to the type of the original or acquire the image data according to the type of the original when the driving unit pauses during conveyance of the original. Change the time to stop, or do at least one of
The image reading apparatus according to claim 1. The document conveying means transmits power from the driving means to the document via a gear train composed of a plurality of gears;
The image reading apparatus according to claim 1. The reading control means controls the reading means to read the original and control the image data when the driving means resumes driving of the original conveying means after the driving means pauses during the original conveying. , The acquisition of the image data is resumed with a delay from the start of the operation of the driving means.
The image reading apparatus according to any one of claims 1-6.