JPH0565352B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method for controlling the operation of a serial printer carriage for correcting positional deviation during operation of the carriage.

(Background Art) In conventional printers, the sensor that detects the position of the carriage is located at the origin, so even if the position of the carriage shifts for some reason during printer operation, this state cannot be detected. . As a result, the printing may deviate from the predetermined printing position, and there is a risk that the life of the print head will be shortened, especially in the case of blank printing.

(Problems to be solved by the invention) The present invention eliminates the above-mentioned drawbacks by detecting the positional deviation of the carriage during printing and automatically correcting the positional deviation of the carriage when it occurs. purpose.

(Structure and operation of the invention) FIG. 1 is a block diagram showing an embodiment of the invention. In the figure, 1 is a sensor that optically detects the position of the carriage CR, and is located at a position B along the carriage CR on the right side in the drawing by a distance L from the origin A, which is the home position when printing. point is the sensor detection position (1' is the sensor position in the conventional method,
In other words, it is at the same position as the origin A. ), when the shutter 11 (described later) passes the detection position, it outputs a detection signal 12 of level l to the counter 3 (described later), and 2 is a count value from the counter 3 (described later) in order to control the amount and direction of movement of the carriage CR. 13 and a carriage controller that supplies a control signal 15 to a driver 7 (described later) based on a correction signal 14 from an error processing unit 6 (described later); a counter 4 which starts counting backwards in response to the l level detection signal 12 of
5 is a storage unit that stores a count value “L” corresponding to the distance L from the detection position of the sensor 1, and sets the count value “L” in the counter 3 according to a control signal 19 from the carriage controller 2; A calculation unit 6 compares the count value 13 from the storage unit 4 with the count value “L” from the storage unit 4, and a calculation unit 6 determines the calculation result of the calculation unit 5 and outputs a determination signal 16 (for example:
As a result of subtracting the count value that is stepping back and forth from the predetermined value "L", when the result finally becomes the value "L", the carriage CR will be located at the origin A)
7 is a driver, which sends a correction signal 14 to automatically correct the position of the carriage CR, and sends an alarm signal 17 to an alarm device (not shown) if desired. Power supply based on 15
18 is supplied to the motor 8 to drive the motor 8.
A belt 9 is connected to the motor 8, and a print head 10 is mounted thereon. Reference numeral 11 denotes a shutter for blocking, for example, an optical path (not shown) in the sensor 1, and when the shutter 11 is located on this optical path, its detection signal becomes a detection state.

FIG. 2 is a diagram showing a detection signal of the sensor 1 of FIG. 1. When the sensor 1 is detecting the shutter 11, the level is L, and when the sensor 1 is not detecting the shutter 11, the level is H. Therefore, at point B in FIG. 1, where the shutter 11 is detected, the output of the sensor 1 becomes L level, and the counter 3 that receives this detection signal 12 has a memory section 4.
The count value "L" is set. Therefore, point A is located a predetermined distance L from point B to the left in the drawing. Note that at these positions, the count of the counter 3 maintains the count value as long as there is no displacement of the carriage 10.

Next, the origin finding operation will be explained based on the flowchart shown in FIG. 3A.

First, when the power is turned on, it is determined whether the content of the detection signal 12 of the sensor 1 is detecting the shutter 11 (L level or H level) (step 301). level), then the carriage controller 2 is
0 in the forward direction (to the right in FIG. 1) via the driver 7, motor 8 and belt 9 (steps 302, 303), and returns to the initial process (step 301). Processing such a loop (steps 301~
303), when the shutter 11 comes to a position where the detection signal 12 of the sensor 1 becomes H level, that is, when the left end of the shutter 11 in the illustration comes to a position on the right side and adjacent to the sensor position of the sensor 1, the carriage The controller 2 moves the carriage CR in the reverse direction via the driver 7, motor 8 and belt 9 (steps 304, 305). When the sensor 1 is shut off by the shutter 11, it sends out a detection signal 12 of l level, so the carriage controller 2
causes the counter 3 to set the contents of the storage section 4, that is, the count value "L" corresponding to the distance L (steps 306 to 308).

Since the count value of the counter 3 is sent to the carriage controller 2, the carriage controller 2 continues until the content becomes 0, that is, the distance L.
Then, the carriage 10 is further moved in the reverse direction (steps 309 and 310). As a result, the carriage CR is set to the correct home position A, and the home search operation when the power is turned on is completed (step
311). When this origin finding operation is completed, the printer becomes capable of online operation.

Furthermore, the carriage controller 2 is connected to the driver 7.
An update instruction is also issued to the counter 3 every time a drive instruction is issued to the counter 3. As a result, when the carriage 10 moves in the forward direction, the count of the counter 3 is incremented, and when the carriage 10 moves in the reverse direction, it is decremented.

Therefore, the count value of the counter 3 is "0" at the origin A in FIG. 1, and "L" at the point B. At these positions, the count value of the counter 3 maintains the count value as long as there is no displacement of the carriage 10.

Next, reference will be made to a flowchart for detecting abnormal operation of the carriage CR shown in FIG. 3B. When the l level of the detection signal 12 of the sensor 1 is output while the printer is operating (including artificial movement while the carriage CR control is stopped) (step 330), the counter 3 calculates the current count value. 5 (step 332). The calculation section 5 compares the count value of the counter 3 with the count value "L" which is the set value of the storage section 4, and sends the calculation result to the error processing section 6 (step 334). When the result of this calculation is not 0, that is, when the two are not equal (the difference is due to the carriage movement due to artificial or abnormal operation rather than the normal operation of the device such as the motor 8) (step 338), based on the correction signal 14 for position correction from the error processing unit 6, the carriage controller performs a position correction operation (repeat forward or reverse operation until the calculation result becomes 0) (step 338).
340-345). Also, if desired (indicated by dotted line)
When the calculation result does not become 0 in step 334, the carriage CR is stopped and the alarm signal 17 is sent out (steps 336 and 337).

In this way, in the automatic position correction process, the carriage is
By moving the carriage CR until the difference between the CR count and the distance L becomes 0, it is corrected to the correct position (point B). Steps 336, 337
Then, an alarm signal 17 is sent to stop the operation of the carriage CR.

(Effects of the Invention) As explained above, according to the present invention, the sensor is disposed at a predetermined position on the movement path of the carriage. Then, when the power is turned on, the carriage is moved in the reverse direction, whereby the sensor detects the carriage and a predetermined value L is read out from the storage section.
This predetermined value L is set in the counter. Thereafter, the carriage is further moved in the reverse direction while decrementing the counter each time the carriage is moved until the counter value reaches zero, and the carriage stops when the counter value reaches zero. This position is the origin of the carriage, and the value of the counter becomes zero at this origin.

In other words, the sensor is disposed at a position shifted in the forward direction by a predetermined value L in terms of the count value of the counter from the origin of the carriage. As a result, when the carriage returns to the origin, the carriage always passes the sensor, and it is possible to monitor the displacement of the carriage based on the output of this sensor.

Therefore, it is possible to determine the origin of the carriage and monitor the positional deviation of the carriage with one sensor, and it is possible to monitor the positional deviation of the carriage without increasing the number of sensors compared to the past. It becomes possible.

Further, according to the present invention, when the sensor detects a carriage during a printing operation, the value of the counter is checked. The value of the counter at this time is the predetermined value L mentioned above if there is no positional deviation of the carriage, and becomes a value larger or smaller than the predetermined value L if a positional deviation of the carriage occurs. If the value of the counter at this time is greater than or less than the predetermined value L, a difference with respect to the predetermined value L is calculated, and the carriage is moved by an amount corresponding to this difference.

That is, each time the sensor detects the carriage during a printing operation, it is checked whether or not the carriage has shifted in position, and the shift in the carriage is corrected.

Therefore, even though the position of the carriage may shift temporarily, when the carriage returns to its origin, that is, when the sensor detects the carriage, the position shift of the carriage is detected and corrected. Ru. This prevents printing from continuing with the carriage being misaligned, making it possible to minimize printing misalignment. Furthermore, it is possible to solve the problem of blank printing, which is caused by the printing being deviated from a predetermined printing position, which has been described as a conventional problem.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a carriage operation control mechanism showing an embodiment of the present invention, Fig. 2 is a time chart of the detection signal of sensor 1 shown in Fig. 1, and Fig. 3A
and B are flowcharts of the control of the carriage shown in FIG. DESCRIPTION OF SYMBOLS 1... Sensor, 2... Carriage controller, 3... Counter, 4... Storage section, 5... Arithmetic section, 6... Error processing section, 7... Driver, 8...
...Motor, 9...Belt, 10...Carriage,
11... Shyatsuta.

Claims (1)

[Scope of Claims] 1. A serial printer that prints by moving a carriage on which a printing head is mounted by a motor driven by power supplied from a driver based on a control signal from a carriage controller, which A carriage operation control method for controlling movement, comprising: moving the carriage to a position near a detection position of a sensor disposed at a predetermined position along a movement path of the carriage and to a position not detected by the sensor; and printing. a drive unit that reads out a predetermined value from a storage unit that stores a predetermined value corresponding to a distance between a home position of the carriage and a detection position of the sensor, and moves the carriage; setting the predetermined value in a counter that counts in conjunction with a drive signal from the carriage controller, and driving the motor by supplying power from the driver based on the control signal from the carriage controller to move the carriage to the a step of moving the carriage in the direction of the origin position and stopping the movement of the carriage when the count value of the counter, which changes in accordance with the amount of movement, reaches zero; and normal printing by moving the carriage. When a detection signal is output from the sensor during operation,
The count value of the counter and the predetermined value are checked by the arithmetic unit to see if they match, and if the contents of the counter and the predetermined value do not match, the count value of the counter and the predetermined value are compared. The calculation unit calculates the difference between the two values, and the carriage controller is controlled via the error processing unit based on the calculation result, and the power is supplied from the driver in accordance with the control signal from the carriage controller. The method comprises the step of driving the motor to move the carriage by the amount of the difference calculated by the calculation section, thereby correcting the positional deviation of the carriage and setting the carriage to the correct position again. Carriage operation control method.