JP2006025290A - Image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid the formation of a seam in reading image data when an image reading operation stops once or restarts in an image reading apparatus. <P>SOLUTION: The apparatus is provided with an image reading part which reads a draft, a driving part which stops once or restarts the reading operation of the draft, a period counting part which counts the reading period of the image reading part and the driving period of the driving part, a difference period counting part which counts a time difference of the reading period and the driving period in the one-time stop of the reading operation, and an approach activation setting part which sets a time until the approach activation of the driving part in the restart of the reading operation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image reading apparatus such as a facsimile or a scanner.

  Conventionally, it is desired that an image reading apparatus is equipped with a memory that stores all data until the read data is read from an external device such as a computer. The situation is difficult due to the increase. Therefore, in order to limit the amount of memory installed, an image reading interruption / resumption function is required.

  A conventional image reading interruption / resumption operation will be described. When the reading speed for reading an image is faster than the reading speed from the external apparatus, the difference data is accumulated in the memory in the apparatus. When the memory is full, reading is interrupted. After that, when the memory becomes free by reading from the external device, reading is resumed from the position where it was interrupted.

  A conventional image reading apparatus will be described below.

  FIG. 6 shows a block diagram of a conventional image reading apparatus. In the figure, reference numeral 101 denotes a CCD for converting an image into an electric signal. An image processing circuit for converting an electric signal of 102 into image data is converted into digital data, and the image data is stored in a memory 103. Reference numeral 104 denotes an interface circuit for transferring stored image data to an external device 105. Reference numeral 109 denotes a motor pulse timer for generating an interval for sending a pulse to the stepping motor. The pulse generated here sends an interrupt signal to the CPU 106 and enters the motor driver 108 to drive the stepping motor 107. FIG. 7 is a timing chart of conventional image reading interruption / resumption, and FIG. 8 is a flowchart of conventional image reading interruption / resumption. The operation will be described below according to the flowchart.

  First, when an image reading is started by driving a motor pulse timer or an image control circuit (step S801), the output from the motor pulse timer enters the stepping motor, the document is conveyed, and one line is output by the CCD in synchronization with the line sync. The image data read every time is digitized by the image control circuit and stored in the memory.

  Next, it is determined whether or not the reading of the original has been completed. If completed, the process ends (step S802).

  It is determined whether the memory for storing the image is full (step S803). If not, the reading is continued. When it is full, it goes to the interruption process.

  An instruction for interrupting image reading is issued to the image control circuit (step S804), and the image control circuit reads the line at the time when the instruction for interruption is received, and then stops reading.

  Simultaneously with the stop of reading, the conveyance of the document is slowed down by controlling the motor pulse timer to stop the conveyance (step S805).

  Return the document to resume scanning. The motor pulse timer is driven by the number of steps added by the number of steps moved from the reading stop position in slowdown and the number of steps up to resume reading, and the motor is reversed by the motor driver to return the document and stop (step) S806).

  Here, it is determined whether the memory is empty (step S807), and it is determined whether the external device reads the image data from the memory via the interface circuit to determine whether the memory is empty. If not, wait for it to be free. When it becomes available, the process proceeds to reading restart processing.

  Next, the motor step timer is driven to slow up the motor and convey the document (step S807).

When the slow-up is completed, the image control circuit is instructed to resume reading (step S808). The image control circuit resumes image reading from the next line sync instructed, and returns to the end of reading (step S802).
JP 2001-217996 A

  However, in the above method, since the line sync and the motor pulse are not synchronized as shown in the timing chart of FIG. 7, the time difference T1 between the motor pulse and the line sync at the time of interruption and the motor pulse and the line at the restart are resumed. The sync time difference T2 is not the same. The position of the motor pulse immediately before the reading is stopped is the same as the position of the motor pulse immediately before the reading is restarted. However, since the reading is synchronized with the line sync, the reading is stopped after T1, and the reading is started after T2. Therefore, there is a problem that the difference between T1 and T2 is read twice or missing.

  Further, when the memory is full, reading of the image is interrupted, and when the memory is empty, the image is duplicated or missing by the difference between T1 and T2.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image reading apparatus that can eliminate the seam of an image by interrupting / resuming a reading operation at the time of image reading.

  According to the present invention, when the image reading is interrupted / resumed, the position when the image reading is interrupted can be matched with the position when the reading is restarted. Thus, an image reading apparatus capable of interrupting / resuming image reading that does not become missing or lost can be obtained.

  According to the image reading apparatus of the present invention, since the position when the image reading is interrupted and the position when the reading is restarted can be matched, there is no seam when the image reading is interrupted / resumed. The effect that can be obtained.

  According to the first aspect of the present invention, an image reading unit that reads a document, a drive unit that temporarily stops or resumes a document reading operation, a reading cycle of the image reading unit, and a drive cycle of the drive unit are counted. Periodic timing unit, differential period timing unit that measures the time difference between the reading cycle when the reading operation is temporarily stopped and the driving cycle, and the start-up operation that sets the time until the driving unit starts up when the reading operation is resumed An image reading apparatus including a setting unit, wherein a reading operation start position is determined based on a time difference between a reading cycle and a driving cycle when reading operation is temporarily stopped, so that a seamless image can be obtained. It has the effect.

According to a second aspect of the present invention, an image reading unit that reads a document, a drive unit that temporarily stops or resumes a document reading operation, and a reading cycle of the image reading unit and a drive cycle of the drive unit are timed. Periodic timing unit, differential period timing unit that measures the time difference between the reading cycle when the reading operation is temporarily stopped and the driving cycle, and the start-up operation that sets the time until the driving unit starts up when the reading operation is resumed An image reading apparatus including a setting unit and a position adjusting unit that aligns a temporary stop position and a restart position of a reading operation, based on a time difference between a reading cycle and a driving cycle when the reading operation is temporarily stopped In addition, since the reading operation start position is determined, there is an effect that a seamless image can be obtained.

  The invention according to claim 3 of the present invention is the image according to claim 1 or 2, wherein the difference period measuring unit measures the time from the reading period when the reading operation is temporarily stopped to the driving period immediately after that. In the reading apparatus, since the reading resumption position is determined by measuring the time difference between the reading cycle and the driving cycle once stopped, the reading position can be adjusted with higher accuracy.

  The invention according to claim 4 of the present invention is the image according to claim 1 or 2, wherein the start-up start setting unit sets a time from the reading cycle when the reading operation is temporarily stopped to the start-up of the driving unit. In the reading apparatus, since the time from the slow-up at the time of resuming the reading to the time at which the reading driving is started is set, there is an effect that the alignment between the reading stop position and the reading resuming position can be performed with high accuracy.

  The invention according to claim 5 of the present invention measures the image reading means for reading the original, the driving means for temporarily stopping or resuming the original reading operation, and the reading period of the image reading means and the driving period of the drive unit. Time measuring means, differential period measuring means for measuring the time difference between the reading period and the driving period when the reading operation is temporarily stopped, and an approach start setting means for setting a time until the start of the driving section when the reading operation is resumed And a position adjusting means for aligning the temporarily stopping position and the restarting position of the reading operation, based on the time difference between the reading cycle and the driving cycle at the time of temporarily stopping the reading operation, Since the reading operation start position is determined, there is an effect that a seamless image can be obtained.

  The invention according to claim 6 of the present invention is the image reading apparatus according to claim 5, wherein the difference period measuring means measures the time from the reading period when the reading operation is temporarily stopped to the driving period immediately thereafter. In addition, since the reading restart position is determined by measuring the time difference between the reading cycle and the driving cycle once stopped, there is an effect that reading position alignment can be performed with higher accuracy.

  The invention according to claim 7 of the present invention is the image reading apparatus according to claim 5, wherein the start-up starting means sets the time from the reading cycle when the reading operation is temporarily stopped to the start-up of the driving unit. In addition, since the time from the slow-up at the resumption of reading to the start of the reading drive is set, there is an effect that the alignment between the reading stop position and the reading resumption position can be performed with high accuracy.

  According to an eighth aspect of the present invention, a first step in which the image reading means reads the image information, a second step in which the storage means stores the image information, and a central control means in which the image information in the storage means is stored. A third step for determining the accumulation state, a fourth step in which the difference period measuring means measures the time difference between the reading period and the driving period, and a fifth step in which the approach start setting means sets the time until the start of the drive means. An image reading method comprising: a sixth step in which the position adjusting means aligns the reading stop position and the reading start position, based on a time difference between the reading cycle and the driving cycle when the reading operation is temporarily stopped. In addition, since the reading operation start position is determined, there is an effect that a seamless image can be obtained.

  According to a ninth aspect of the present invention, an image sensor for reading an image, a memory for temporarily storing the read image data, a stepping motor for conveying the original, an interruption instruction means for interrupting the reading, and reading restart And a counter that counts the time from when reading is interrupted to the first motor pulse. When instructed to stop, reading is interrupted at the next line sync, and the first motor pulse after the interruption Or until the interruption from the motor pulse just before the interruption, slow down and stop the conveyance, and when instructed to resume reading, slow down and slow up to resume Adjust the time from the line sync to the start of slow-up according to the time measured when the document is returned and interrupted by the moving distance. The image reading apparatus that resumes reading from the same document position as the original document position interrupted by the reading operation, the reading operation start position is determined based on the time difference between the reading cycle and the driving cycle when the reading operation is temporarily stopped. There is an effect that a seamless image can be obtained.

  The present invention is adapted to match the reading position in reading interruption / resumption, and thereby has the effect of eliminating the seam of the image.

  Embodiments of the present invention will be described below.

  FIG. 1 is a block diagram of an image reading apparatus according to an embodiment of the present invention, FIG. 2 is a read interruption timing chart according to an embodiment of the present invention, and FIG. 3 is a read restart timing according to an embodiment of the present invention. 4 is a flowchart for interrupting reading in an embodiment of the present invention, and FIG. 5 is a flowchart for restarting reading in an embodiment of the present invention. The following description will be given along these drawings. Here, the same number is attached | subjected about the structure same as the prior art, and description is abbreviate | omitted.

  In FIG. 1, reference numeral 110 denotes a difference period measuring means / difference period measuring unit (hereinafter referred to as a difference counter between a line sync and a motor pulse) for measuring the time from the line sync when the image reading is stopped to the motor pulse immediately after that. Is a start-up start setting means / start-up start setting unit (hereinafter referred to as a motor start delay timer) for setting the time from the line sink to the motor slow-up start-up.

  The operation will be described below with reference to the reading interruption flowchart of FIG. 4 and the reading restart flowchart of FIG.

  First, in FIG. 4, a CPU (hereinafter referred to as a central control unit / central control unit) 106 determines whether or not a document has been read (step S401). If it is completed, the process is terminated. continue. The central control unit (central control unit) 106 determines whether or not the storage unit / storage unit (hereinafter referred to as memory) 103 for storing the image is full (step S402). If not, the reading is continued. When it is full, it goes to the interruption process.

  Here, the central control means (central control unit) 106 issues an instruction to interrupt image reading to the image control circuit 102 (step S403), and the image control circuit 102 receives the next line sync (reading cycle) when the instruction to interrupt is received. ) And stop reading.

  Next, the central control means (central control unit) 106 determines whether or not a read stop interrupt has occurred from the motor pulse timer 109 (step S404), and confirms whether or not an interrupt instruction has been executed by the generation of the interrupt. Wait until occurs. Next, after the reading is stopped, it is determined whether or not the first motor pulse interruption occurs, and the process waits until it occurs (step S405).

  Next, T2 (shown in FIG. 2) is read from the differential counter (difference period measuring means / difference period timing unit) 110 between the line sync and the motor pulse, and T3 is calculated and stored by subtracting T2 from the motor pulse period T4. Then (step S406), the motor pulse timer is controlled to slow down and the conveyance is stopped (step S407), and then the original is returned to resume reading (step S408). Then, the motor pulse timer 109 is driven by the number of steps obtained by adding the number of steps moved in the slowdown from the reading stop position and the number of steps up to resume the reading, and the motor driver 108 reverses the stepping motor 107 to reverse the original. Return to, stop and move to resume reading.

  From here, the reading restart operation will be described with reference to FIG.

  It is determined whether or not the memory 103 is free and waits until the memory 103 is free (step S501).

  Next, the line sync is set so that the time obtained by adding the slow-up time T6 (shown in FIG. 3) and the time T3 (shown in FIG. 2) from the motor pulse immediately before the reading stop to the reading stop becomes the same as the line sync timing. Delay time T5 (shown in FIG. 3) is calculated (step S502), and it is determined whether a line sync interrupt has occurred. In order to delay T5 time from the line sync, a line sync interrupt is awaited (step S503).

  Here, the position adjusting means (position adjusting unit) 106 sets the delay time T5 from the line sync in the motor start delay timer 111 (step S504), and determines whether the motor start delay timer 111 has timed up (step S505). . Thereafter, it waits for the delay T5 from the line sync to time up.

  Next, the position adjusting means (position adjusting unit) 106 drives the motor pulse timer 109 to slow up the stepping motor 107 and start conveyance (step S506). Determination is made (step S507). At this time, the reading start is started from the next line sync instructed to read, and therefore, it waits for the line sync one before the start.

  Finally, the position adjusting means (position adjusting unit) 106 instructs resumption of reading (step S508), whereby reading is resumed from the next line sync. The next line sync is the position of the document that has passed T3 time after the slow-up, and matches the position of the document that stopped reading, so the read image will not be duplicated or missing, and will be a seamless image. .

  Needless to say, the image reading apparatus according to the embodiment of the present invention can adjust the reading cycle and the driving cycle even when the reading operation is decelerated and then accelerated.

  The image reading apparatus according to the present invention has the above-described configuration, can seamlessly display an image when the reading operation is temporarily stopped or restarted, and is useful for a scanner, a facsimile, a copying machine, or the like that reads an image.

1 is a block diagram of an image reading apparatus according to an embodiment of the present invention. Read interruption timing chart in one embodiment of the present invention Read restart timing chart in one embodiment of the present invention Read interruption flowchart in one embodiment of the present invention Read restart flowchart in one embodiment of the present invention Block diagram of a conventional image reading apparatus Conventional timing chart for interrupting / resuming image reading Conventional flow chart for interrupting / resuming image reading

Explanation of symbols

101 CCD
102 Image control circuit 103 Memory (storage means)
104 interface circuit 105 external device 106 CPU (position adjustment means / position adjustment unit / central control means)
107 Stepping motor 108 Motor driver 109 Motor pulse timer 110 Line sync and motor pulse difference counter (difference period timing means / difference period timing section)
111 Motor start delay timer (running start setting unit / running start setting means)

Claims (9)

An image reading unit that reads a document, a drive unit that temporarily stops or resumes a document reading operation, a period measuring unit that measures a reading period of the image reading unit and a driving period of the driving unit, and a reading operation are temporarily stopped A difference period timing unit that counts a time difference between the reading cycle and the driving cycle at the time, and a start-up start setting unit that sets a time until the start-up of the drive unit when the reading operation is resumed. A characteristic image reading apparatus. An image reading unit that reads a document, a drive unit that temporarily stops or resumes a document reading operation, a period measuring unit that measures a reading period of the image reading unit and a driving period of the driving unit, and a reading operation are temporarily stopped A difference period timing unit that counts a time difference between the reading cycle and the driving cycle, a run start setting unit that sets a time until the start of the driving unit when restarting the reading operation, and a reading operation An image reading apparatus comprising: a position adjusting unit that performs alignment between a stop position and a resume position. 3. The image reading apparatus according to claim 1, wherein the difference period measuring unit measures a time from a reading period when the reading operation is temporarily stopped to a driving period immediately after the reading period. The image reading apparatus according to claim 1, wherein the start-up start setting unit sets a time from a reading cycle when the reading operation is temporarily stopped to start-up start of the driving unit. Image reading means for reading a document, driving means for temporarily stopping or resuming a document reading operation, timing means for measuring the reading period of the image reading means and the driving period of the driving unit, and the reading operation are temporarily stopped Difference period timing means for measuring the time difference between the reading period and the driving period at the time, running start setting means for setting the time until the starting start of the drive unit when restarting the reading operation, and once of the reading operation An image reading apparatus comprising: a position adjusting unit that aligns a stop position and a restart position. 6. The image reading apparatus according to claim 5, wherein the difference period measuring means measures a time from a reading period when the reading operation is temporarily stopped to a driving period immediately thereafter. 6. The image reading apparatus according to claim 5, wherein the start-up starting means sets a time from the reading cycle when the reading operation is temporarily stopped to the start-up start of the driving unit. A first step in which the image reading means reads the image information; a second step in which the storage means stores the image information; a third step in which the central control means determines the accumulation state of the image information in the storage means; A fourth step in which the time measuring means measures the time difference between the reading cycle and the driving cycle, a fifth step in which the start-up start setting means sets the time until the start-up of the driving means, and a position adjusting means in the reading stop position and the reading start position. And a sixth step of performing alignment with the image reading method. An image sensor that reads an image, a memory that temporarily stores the read image data, a stepping motor that transports an original, an interruption instruction unit that interrupts reading, a restart instruction unit that resumes reading, and a reading interruption A counter that counts the time from the start to the first motor pulse is provided. When an interruption is instructed, the reading is interrupted at the next line sync, and the time from the interruption to the first motor pulse or the motor immediately before the interruption The time from pulse to interruption is timed and slowed down to stop conveyance, and when reading is instructed to resume, time is slowed down and the original is returned by the slow-up movement distance to resume and timed. The position of the original interrupted by adjusting the time from the line sync to the start of slow-up according to the time Image reading apparatus characterized by resuming the reading from the same original position.

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