JP3174693B2 - Image scanner control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image scanner control device for inputting image data such as figures and photographs to a personal computer or a desktop publishing device (DTP).
In particular, control is performed to stop scanning according to the length of the document.

[0002]

2. Description of the Related Art An image scanner for reading figures and photographs and converting them into image data (hereinafter simply referred to as a scanner).
Is used as an input device of a personal computer or a DTP, and is used for image reading of a copying machine.

In a conventional scanner, a carriage equipped with a light source and an image reading sensor always scans a fixed reading range irrespective of the size of a document to read image data. While this reading continues,
The personal computer or DTP cannot proceed to the next data processing, and time is wasted while the carriage scans a place where there is no original. A scanner control device for improving the operation of such a scanner is disclosed in Japanese Patent Application Laid-Open No. 3-7026.
No. 2 is proposed.

[0004] As shown in FIG.
A counter 44 for counting pulses output each time the carriage 45 moves one resolution in the sub-scanning direction;
A CPU 41 which is built in the TP 46 and controls the operation of the entire system to which the scanner 45 is connected, a register 42 in which a register value is directly set from the CPU 41 by a keyboard operation of a personal computer or the like, and a register value and a counter set in the register 42 Comparator that detects match with 43 count value
And 43.

In this device, the counter 44 counts the pulse (sub-scanning signal) output from the scanner 45 and outputs the count value to the comparator 43.

On the other hand, a value corresponding to the size of a document to be read is input to the register 42 from a keyboard of a personal computer or the like, and the register 42 stores the value.

The comparator 43 compares the value set in the register 42 with the count output of the counter 43, and outputs a match signal when they match, that is, when the carriage moves by the length of the document. . This match signal is C
The interrupt is input to the PU 41, and the CPU 41 terminates the input of the image data to the personal computer or the like.

[0008] At this time, the scanner performs scanning with the remaining reading range without outputting image data. In other words, the personal computer or the like can proceed to the next data processing without waiting for the completion of scanning by the scanner.

[0009]

However, in this conventional scanner control device, even if the reading of the image data is completed, the movement of the carriage continues until the entire reading range is scanned. Can not start immediately.

In order to stop the carriage at the end of the reading of the image data, it is conceivable to issue a deceleration command to the control motor of the carriage from the CPU 41 which has received the interrupt of the coincidence signal. Causes the following problems.

In advanced models such as personal computers and copiers in recent years, the CPU not only controls the scanner, but also executes, for example, a memory device under the control of the CPU.
It controls several combined operations, such as performing X transmission processing, sending data to a printer, and performing a copy operation.

Therefore, when the CPU is performing another processing, it may not be possible to interrupt the carriage deceleration processing with good timing. In the worst case,
It is possible that the carriage will hit the housing of the scanner device without the CPU taking time for another interrupt service and receiving the interrupt service for stopping the carriage. Therefore, it is difficult to stabilize the movement of the carriage by the control depending on the CPU.

An object of the present invention is to provide an image scanner control apparatus capable of stably controlling the amount of movement of a carriage of a scanner in accordance with the size of a document. I have.

[0014]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems .
Home position sensor to detect passage and scanner
Of the sub-scanning signal output when the
And the registration value set in accordance with the
Detects a match, outputs a match signal, and
Control means for controlling the surroundings according to the size of the document;
Acceleration / deceleration that controls acceleration or deceleration of the moving speed of the canner
Control means and detection by the home position sensor
The acceleration and deceleration control means is activated by the signal and the coincidence signal.
And the acceleration / deceleration control means controls the speed of movement of the scanner.
Acceleration / deceleration control activation means for performing a degree of deceleration control.
The acceleration / deceleration control means is provided at the home position.
When the detection signal by the sensor or the coincidence signal is generated
No pulse frequency to adjust step motor drive
Or according to the acceleration / deceleration pattern describing the number of steps
It controls the movement of the scanner .

[0015]

[0016]

[0017]

Therefore, when the carriage has finished scanning the length of the document, the image reading ends and the movement of the carriage stops. When the carriage returns to the home position, the moving speed starts decreasing when the carriage passes the position of the home position sensor, and the carriage stops at the home position.

At this time, if there is an error in the mounting position of the home position sensor, the carriage does not stop at the correct position. Therefore, the deceleration pattern from the home position sensor to the correct stop position is set for each individual scanner and stored in the storage means, and the acceleration / deceleration control means performs deceleration control in accordance with this pattern, whereby the Mounting errors can be absorbed.

In this image scanner control apparatus, the movement of the carriage is controlled by the acceleration / deceleration control means and the acceleration / deceleration control activation means without depending on the CPU. Therefore, the CPU can perform other processing during that time, and can safely stop the carriage even during the combined operation of the CPU.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image scanner control apparatus according to an embodiment of the present invention includes, as shown in FIG. 1, a scanner apparatus S having a motor M as a drive source of a carriage and a home position sensor HP installed near a home position. ,
Motor control means 7 for driving the motor M, acceleration / deceleration control means 6 for controlling acceleration / deceleration of the motor control means 7, and acceleration / deceleration control activation means 5 for activating the acceleration / deceleration control means 6
And a CPU 1 such as a personal computer or a copying machine, a register 2 for holding a registration value set by the CPU 1, and a sub-scanning signal (LINESYNC) generated from the scanner S.
A counter 3 for counting the number 8; a comparator 4 for outputting a match signal when the register value held in the register 2 matches the count output of the sub-scanning signal counted by the counter 3; And storage means 14 for storing.

The acceleration / deceleration control starting means 5 includes an AND circuit 15 for outputting a high level signal when a coincidence signal is input, and a high level signal when the carriage returning to the home position is detected by the home position sensor HP. An AND circuit 16 that outputs a level signal; and an OR circuit 17 that outputs a high-level signal when any of the high-level signals of the AND circuits 15 and 16 or the motor start signal 11 output from the CPU 1 is input. A high-level Q signal is output when the acceleration / deceleration end signal 12 is output from the acceleration / deceleration control means 6, and the D flip-flop 18 reset by the output of the OR circuit 17; OR circuit for outputting a high-level signal when any one of signals indicating rejection of acceptance (inversion signal of ACK signal) of acceleration / deceleration control means 6 is input 19 and a high-level request signal (RE) when LINESYNC8 is output.
Q), and is reset by the output of the OR circuit 19.
And a flip-flop 20.

As shown in FIG. 2, the scanner S places the original G (length y in the sub-scanning direction: Y> y) in a reading range R whose length in the sub-scanning direction is Y, and connects the carriage C with a thick line. The image of the original G is read while moving in the direction of the arrow. FIG.
Shows a state in which the carriage C is at the home position. The home position sensor HP is located at the reading position origin of the reading range R, and the carriage C
Outputs a high-level home position signal 13 when it is on the home position side from the read position origin and a low level when it is on the read range R side.

The scanner S outputs LINESYNC 8 every time the carriage C moves a unit distance in the sub-scanning direction. A register 2 is set with a registration value corresponding to the distance from the origin of the reading position to the edge of the document G (the edge on the side where reading is completed).
When the count value of the SYNC 8 matches, that is, when the position of the carriage C moves to the end edge of the document G, a match signal is output from the comparator 4.

A motor M for driving the carriage C
Is constituted by, for example, a step motor. Upon receiving the motor start signal 11 from the CPU 1, the motor control means 7 outputs a pulse to the step motor to rotate it in the designated direction. The acceleration / deceleration control means 6 controls the frequency of the pulse output from the motor control means 7 over a predetermined number of steps, thereby accelerating / decreasing the step motor.
Adjust deceleration. For this purpose, the acceleration / deceleration control means 6 has a built-in memory for storing a table of acceleration / deceleration patterns. In this memory, acceleration / deceleration patterns describing pulse frequencies and step numbers during acceleration / deceleration are set in advance. Also, as described below, these patterns
It can be set in the storage device 14 and written into the memory of the acceleration / deceleration control means 6 through the CPU 1.

In this image scanner control device, first, the CPU 1 sets the number of sub-scanning signals when the scanner S scans the length y of the original G in the register 2.
Next, the CPU 1 turns on the motor start bit.
The motor start signal 11 starts the motor control means 7 and is also input to the OR circuit 17 of the acceleration / deceleration control start means 5, changes the output of the OR circuit 17 to high level, and resets the D flip-flop 18. .

The carriage direction signal 10 takes a high level when the carriage C moves in the direction of the thick arrow (forward direction) in FIG. 2, and when the carriage C moves in the direction opposite to the thick arrow (reverse direction). Take the low level. When the carriage C moves in the normal rotation direction, the carriage direction signal 10 keeps the output of the AND circuit 16 low even when the home position signal is high (that is,
Only when the carriage C moves in the reverse direction, the output of the AND circuit 16 is changed to high in accordance with the change of the home position signal to high.

When the D flip-flop 18 is reset by the motor start signal 11 and the acceleration / deceleration control means 6 is in an acceptable state (ACK is high level), the output of the OR circuit 19 becomes low level, D
The reset of the flip-flop 20 is released, and the D flip-flop 20 outputs L which is first output from the scanner device S.
The INESYNC 8 outputs a high-level REQ signal to the acceleration / deceleration control means 6.

The acceleration / deceleration control means 6 to which the REQ signal has been input
Is the motor M according to the acceleration pattern set in the memory.
Control the acceleration of the vehicle. When the acceleration of the predetermined number of steps is completed, the acceleration / deceleration control means 6 outputs an acceleration end signal 12 to the D flip-flop 18. The D flip-flop 18 (which has been reset at this time) receives the signal and outputs a high-level Q signal, the output of the OR circuit 19 changes to high level, and the D flip-flop 20 is reset.
The REQ signal stops. The acceleration / deceleration control means 6 stops the acceleration control for the motor control means 7,
Drives the motor M at a constant speed.

FIG. 3 shows the time change of the motor speed at this time. With the rotation of the motor M, the carriage moves in the direction of the thick arrow (forward direction) in FIG. 2. With this movement, the LINESYNC 8 is output from the scanner S one after another, and is input to the D flip-flop 20 and the counter 3. When the reset is released, the D flip-flop 20 outputs a high-level REQ signal to the acceleration / deceleration control unit 6.
Continue to put out. On the other hand, when the home position signal 13 is high, the counter 3 does not start counting the LINESYNC8.

When the carriage C moving in the normal rotation direction passes through the origin of the reading position and the home position signal 13 changes from high to low, the counter 3 counts the sub-scanning signal (LINESYNC) 8 output from the scanner S. Is started, and the count value is input to the comparator 4. The comparator 4 compares the count value with the register value of the register 2, and outputs a match signal 15 to the AND circuit 15 of the acceleration / deceleration control activation means 5 when they match.

The comparator gate signal 9 remains low,
When the signal from the comparator 4 can be received,
When the coincidence signal 15 is input, the output of the AND circuit 15 becomes high level, and the OR circuit 17 outputs a high level signal.
The flip-flop 18 is reset. As a result, in the same procedure as above, the D flip-flop 20 sets the LINESYNC
A high level REQ signal is output to the acceleration / deceleration control means 6 in response to the input of 8.

Acceleration / deceleration control means 6 receiving the REQ signal
Is the motor control means 7 according to the table of the deceleration pattern.
The motor control means 7 reduces the rotation of the motor M and stops the carriage C at the correct position (the deceleration curve in the normal rotation direction in FIG. 3). The acceleration / deceleration control means 6 outputs the deceleration end signal 12 to the D flip-flop 18, the D flip-flop 18 outputs a high-level Q signal, the D flip-flop 20 is reset, and the output of the REQ signal stops.

Further, the acceleration / deceleration control means 6 notifies the CPU 1 that the carriage C has stopped by interruption. Upon receiving this notification, the CPU 1 knows that the transfer of the image data from the scanner S has been completed. During this time, the CPU 1 does not need to be involved in the control of the carriage C or the transfer processing of the image data at all.

After that, the CPU 1 turns on the motor start bit to move the carriage C in the reverse direction,
The motor control means 7 is started to reverse the motor M, and at the same time, a motor start signal 11 is sent to the acceleration / deceleration control start means 5.
By turning on this motor start signal, D flip-flop
The reset of 20 is released, and the REQ signal is output from the D flip-flop 20 to the acceleration / deceleration control means 6 by the input of the first LINESYNC8.
The acceleration of the motor control means 7 is controlled according to the acceleration pattern.

When the acceleration in the predetermined step is completed, the acceleration / deceleration control means 6 outputs the acceleration end signal 12 to the D flip-flop 18
, As a result, the D flip-flop 20 is reset, and the REQ signal stops. The acceleration / deceleration control means 6 stops the acceleration control for the motor control means 7, and the motor control means 7 drives the motor M in the reverse direction at a constant speed.

When the carriage C returns to the reading position origin, the home position signal 13 changes from low to high,
Since the carriage direction signal 10 in the reverse direction is low,
The output of the AND circuit 16 becomes high level. As a result, D
The flip-flop 18 is reset, so that the reset of the D flip-flop 20 is released and the next LINES
The REQ signal is output to the acceleration / deceleration control means 6 by the input of the YNC 8.

The acceleration / deceleration control means 6 controls deceleration of the motor control means 7 according to the deceleration pattern.
Reduces the rotation of the motor M and stops the carriage C at the home position correctly. The acceleration / deceleration control means 6 outputs a deceleration end signal 12 to the D flip-flop 18, and a high-level Q signal is output from the D flip-flop 18,
As a result, D flip-flop 20 is reset and RE
The Q signal stops.

FIG. 3 shows a time change of the motor speed controlled by the motor control means 7 and the home position signal 13.
And the LINESY input to the comparator 4
5 shows a time change of the measured value of NC8.

As shown in FIG. 3, when the carriage C moves in the normal rotation direction, a sharp angular acceleration is performed so that the moving speed of the carriage C can be maintained at a constant speed before the carriage C reaches the origin of the reading position. Accelerate with a pattern. on the other hand,
When the carriage C moves in the reverse direction, the carriage C starts decelerating from the reading position origin and the carriage C
Decelerate in a gentle deceleration pattern so that the vehicle can be stopped at the correct home position without hitting the housing.

The acceleration / deceleration pattern stored in the acceleration / deceleration control means 6 can be set in the storage means 14 in advance, and then stored in the acceleration / deceleration control means 6 under the instruction of the CPU 1. In such a case, there are the following advantages.

The home position sensor HP of the scanner S
If there is a variation in the mounting positions, the distance from this mounting position to the end of the scanner housing will be different for each scanner. Therefore, if the same deceleration pattern is uniformly applied to each scanner, the carriage C decelerated at the position of the home position sensor HP may hit the scanner housing when moving in the reverse direction.

Such a situation can be avoided by setting a deceleration pattern that defines the number of steps from the actual mounting position of the home position sensor HP of each scanner to the position where the carriage C should be stopped. Therefore, by setting a table including such individual deceleration patterns suitable for each scanner in the storage device 14 and storing the table in the acceleration / deceleration control means 6, the mounting error of the home position sensor HP in each scanner device is absorbed. Adjustment can be easily performed.

As described above, in the image scanner control device of the embodiment, the movement range of the carriage can be controlled to the range of the document from which the image data is read, without depending on the CPU 1. In this control, the CPU only activates the scanner and does not participate in controlling the carriage.
Therefore, the carriage can be stopped stably,
During this time, the CPU can execute other processing.

The configuration of the acceleration / deceleration control activation means 5 for controlling the activation of the acceleration / deceleration control means 6 is not limited to the configuration of the embodiment, and generally known control means can be used. .

[0045]

As is apparent from the above description of the embodiment, the image scanner control apparatus of the present invention controls the moving range of the scanner carriage according to the size of the document without increasing the load on the CPU 1. be able to. Therefore, the scanning of the original is completed in a short time, and the next original can be read quickly.

Since the CPU does not need to control the scanner during that time, the CPU can execute other processing such as performing encoding and compression processing on the read image data. Further, while the CPU performs a facsimile transmission process or the like from the memory device under its control, a more advanced complex process such as activating the scanner and sending the read data to the printer to perform a copy operation is also performed. Will be possible.

Further, since the carriage movement control is performed without the CPU, it is possible to avoid a situation in which the carriage hits the scanner housing due to interruption processing in time, and stable control can be performed. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of an image scanner control device according to the present invention;

FIG. 2 is an explanatory diagram showing the configuration and operation of an image scanner controlled by the control device;

FIG. 3 is a timing chart illustrating an operation of a carriage of the image scanner;

FIG. 4 is a block diagram showing a configuration of a conventional image scanner control device.

[Explanation of symbols]

 B Scanner body C Carriage G Original HP Home position sensor M Motor R Scanner reading range S Image scanner 1, 41 CPU 2, 42 Register 3, 44 Counter 4, 43 Comparator 5 Acceleration / deceleration control activation means 6 Acceleration / deceleration control means 7 Motor Control means 8 Sub-scanning signal LINESYNC 9 Comparator gate signal 10 Carriage direction signal 11 Motor start signal 12 Acceleration / deceleration end signal 13 Home position signal 14 Storage device 15, 16 Logical product circuit 17, 19 Logical sum circuit 18, 20 D flip-flop 45 Image Scanner 46 PC

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-70262 (JP, A) JP-A-57-95754 (JP, A) JP-A-57-87669 (JP, A) 297474 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H04N 1/04-1/207

Claims (1)

(57) [Claims] 1. A method for detecting the passage of a scanning start position origin of a scanner.
Home position sensor and sub-scan of scanner
Count value of the sub-scanning signal output when moving in the
Match the registration value set according to the size of the original
Detects and outputs a match signal, and scans the scanner
Control means for controlling according to the size of the scanner;
Acceleration / deceleration control means for controlling acceleration or deceleration of moving speed
And the detection signal from the home position sensor and
Activating the acceleration / deceleration control means by the coincidence signal
The acceleration / deceleration control means reduces the movement speed of the scanner.
And an acceleration / deceleration control activation means for performing control.
The acceleration / deceleration control means may include the home position sensor
With the generation of the detection signal or the coincidence signal,
Pulse frequency or step for adjusting the drive of the step motor
The scan according to the acceleration / deceleration pattern describing the number of steps
An image scanner control device for controlling movement of a scanner.