JPH0740621A - How to determine the home position of a serial printer - Google Patents

Abstract

(57) [Summary] [Purpose] Without using a home position detector,
Provided is a home position determining method for a serial printer, which determines the home position of a print head and reduces the home position detector. A carriage equipped with a print head, a carriage mechanism for moving the carriage by a stepping motor, and a control means for controlling the rotation of the stepping motor are provided. Is collided with a stop member to stop, and the position where the stepping motor is rotated from the stop position by a preset number of steps is set as the home position of the print head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a home position determining method for a serial printer which simplifies the home position determination of a print head.

[0002]

2. Description of the Related Art FIG. 5 shows a print head moving mechanism in a conventional serial printer. Print head 100
Is mounted on the carriage 102, and the carriage 10
2 is supported by a pair of carriage stays 104 and moves left and right. The print head 100 is movable left and right together with the carriage 102. Of course, the carriage stay 104 is similarly fixed to the frame 106 at the other end side, just as the one end side is fixed to the frame 106.

Further, the frame 106 has a carriage 1
A stepping motor 110 is installed as a carriage motor for transporting 02. The timing belt 11 is provided between the timing pulley 112 and the timing pulley 112 attached to the rotary shaft of the stepping motor 110.
4, the carriage 102 is attached to the timing belt 114 in the middle thereof. That is, by the forward rotation, the reverse rotation, or the stop of the stepping motor 110,
The print head 100 together with the carriage 102 can be moved and stopped in a desired direction and position by the rotation of the timing belt 114.

As a home position detecting means of the print head 100, a home position detector is installed on the left side or the right side of the print area. With this print head transfer mechanism,
A home position detector 116 is provided on the left side. The home position detector 116 is composed of, for example, a photo sensor, and interrupts light by the protrusion 118 on the lower surface side of the carriage 102, and outputs a signal indicating the home position.

A control unit 200 is associated with the print head transfer mechanism as a control means as shown in FIG. The control unit 200 includes a CPU 202 and the like, fetches a detection signal of the home position detector 116, gives a print output based on print data from the host computer 300 to the print head 100, and controls the stepping motor 110. Generate output.

By the way, in such a print head transfer mechanism, the carriage 102 has a stepping motor 110.
When the stepping motor 11 moves to the left or right in the print digit direction due to normal rotation or reverse rotation of the
0 may rotate. In this case, the carriage 102
Corresponds to the left end or the right end of the frame 106, and at that time,
In the configuration, the stepping motor 110 is out of step.

The home position detector 116 detects the home position when the power is turned on or when the power is reset. In that case, the stepping motor 110 is rotated so as not to step out, the carriage 102 is moved to the home position sensor area, and the carriage 102 is detected by the home position detector 116. For this home position, the detection signal of the home position detector 116 is received by the control unit and stored in the storage means,
Based on this position, the carriage 102 is moved so that the stepping motor 110 does not step out, and the print head 1 is moved.
A control for causing 00 to perform a printing operation is realized.

FIG. 7 shows home position detection by the home position detector 116 when the power is turned on.
In step S21, the CPU 20 in the control unit 200
After the initialization of 2, the home position detector 116 detects the carriage in step S22. This is the detection of the home position. When the home position detector 116 detects the carriage 102, step S
23, the stepping motor 110 is normally rotated to move the carriage 102 to the right. In step S24, the carriage 102 is detected again, and the carriage 10 is detected.
The carriage 102 is moved to the right side until 2 is not detected. When the carriage 102 is in the undetected state in step S24, the process proceeds to step S25 and the stepping motor 110 is stopped.

Further, in step S22, the carriage 102
Is not detected, or if step S25 has been passed, the process proceeds to step S26, the carriage 102 is moved to the left side, and the carriage 102 is detected in step S27. The transfer operation of the carriage 102 to the left side continues until the carriage 102 is detected. When the carriage 102 is detected in step S27, the process proceeds to step S28, and the stepping motor 110 is stopped. At this time, the carriage 102 stops at the home position position.

In step S29, the print data is received,
The process shifts to the print processing preparation. That is, in step S30, the carriage 102 is moved to the right side, and the process proceeds to step S31 where the rotation amount of the stepping motor 110, for example,
It is determined whether or not it has rotated by 8 steps. The carriage 102 is transported to the right side until the 8-step rotation is completed, that is, to the 8-step position. The eight-step position is the paper edge position, and the carriage 102, that is, the print head 100 is moved to that position. When the 8-step rotation is completed in step S31, the process proceeds to step S32, and the printing operation is performed.

[0011]

In such a serial printer, the home position detector 1 serves as means for detecting the home position of the print head 100.
16 is required, and home position detection processing using the detection signal of the home position detector 116 and its control are required.

Therefore, an object of the present invention is to provide a home position determining method for a serial printer in which the home position of the print head is determined without using such a home position detector and the home position detector is eliminated. And

[0013]

As shown in FIGS. 1 and 2, a home position determining method for a serial printer according to the present invention includes a carriage on which a print head is mounted and a carriage mechanism for moving the carriage by a stepping motor. And a control means for controlling the rotation of the stepping motor, the stepping motor is normally or reversely rotated to cause the carriage to collide with a stop member to stop, and a predetermined number of steps from the stop position are set. A position where the stepping motor is rotated is set as a home position of the print head.

The home position determining method for a serial printer according to the present invention is characterized in that a frame of the serial printer is used as the stop member.

[0015]

When the power is turned on or reset, the stepping motor is normally or reversely rotated to move the carriage and collide with the stop member to stop the carriage. From this stop position, rotate the stepping motor a predetermined number of steps to stop it,
The stop position is the home position. With such a method, the home position detector is not needed at all, and the home position can be reliably and accurately determined from the stop position of the carriage.

A special stopper can be installed on the stop member, but a printer frame can be used. By using such an existing member, it is possible to further simplify the printer in addition to omitting the home position detector.

[0017]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment of a home position determining method for a serial printer according to the present invention. A host computer 4 is connected to the control unit 2 of the serial printer, and print data is given from the host computer 4. In addition, this serial printer has
It also includes a word processor and the like in which the printer and the host computer 4 are built in one housing.

A microcomputer is used for the control unit 2. A central processing unit (CPU) 21 controls a program according to a program and performs calculations for the control. A storage unit, an input / output unit, a display unit, and the like are associated with the CPU 21 according to its control.

The storage means is provided with a ROM 22 and a RAM 23 which constitute a main storage means for storing the data required for the control operation executed by the CPU 21, the control program or various data in the process of calculation. ROM2
Reference numeral 2 is a read-only memory having a control program, a table, etc., and RAM 23 is an occasional write memory for storing data in the middle of calculation, print data, etc. Although not shown,
A storage medium such as a flexible disk can be used as the storage means. Further, the storage means on the host computer 4 side can also be used as an auxiliary storage means of the control unit 2.

An interface (I
/ F) 24 is installed, and print data or the like is input to the I / F 24 from the host computer 4. The external data is taken into the CPU 21 through an input unit such as a sensor receiver (not shown).

Drivers 25, 26 as data output means
Is installed. The carriage transfer output output from the CPU 21 is applied to the stepping motor 6 of the carriage mechanism which constitutes the carriage transfer means through the driver 25. The print output from the CPU 21 is
It is added to the print head 8 through the driver 26.

Next, FIG. 2 shows a concrete embodiment of a print head transfer mechanism having a carriage mechanism. The print head 8 is mounted on a carriage 10, and the carriage 10 is supported by a pair of carriage stays 12 and moves left and right. The print head 8 is movable left and right together with the carriage 10. The carriage stay 12 is fixed to the frame 14.

The frame 14 has a carriage 10
A stepping motor 6 is installed as a carriage motor for transferring the. A timing belt 18 is hung between the timing pulley 16 and the timing pulley 16 attached to the rotation shaft of the stepping motor 6.
The carriage 10 is provided in the middle of the timing belt 18.
Is attached. That is, when the stepping motor 6 rotates normally, reversely, or stops, the print head 8 along with the carriage 10 is moved to a desired direction and position by driving the timing belt 18. In that case, when the stepping motor 6 is rotated more than necessary, the carriage 10 is placed on the right or left side of the frame 14 as a stop member.
Can be stopped by colliding with.

Next, FIG. 3 shows a transfer area of the carriage 10 in the print head transfer mechanism. 14L
Indicates a left stop position of the carriage 10 of the frame 14 as a stop member, and 14R indicates a right stop position of the carriage 10 of the frame 14 as a stop member. Also, H
P indicates a home position position where the carriage 10 should be initialized, and PE indicates an edge position of the sheet 30.

Next, FIG. 4 shows a flowchart showing a method for determining the home position. After turning on the power,
In step S1, the control unit 2 such as the CPU 21 is initialized. In step S2, the stepping motor 6 is rotated to move the carriage 10 to the left. During this transfer
In step S3, it is determined whether the stepping motor 6 has rotated n steps. Here, n step is a preset value, which is a number larger than the number of steps of the stepping motor 6 that the carriage 10 can move in the same direction, and is a value that can reliably step out the stepping motor 6. Therefore, in step S3, the stepping motor 6 is rotated until the stepping motor 6 is out of step.

When the rotation of the stepping motor 6 reaches n steps in step S3, the process proceeds to step S4, the stepping motor 6 is stopped, and then step S
Go to 5. In step S5, the carriage 10 is moved to the right, and the process proceeds to step S6. In step S6, it is determined whether the stepping motor 6 has rotated n ₁ steps. This n ₁ step is the number of steps for returning the stepping motor 6 from the step-out state to the rotation control state, and is set to about 10 steps, for example.

In step S7, the stepping motor 6 that has entered the control state is stopped. This position is the home position position HP. Then, in step S8, data reception is performed. That is, the I / F 24 receives print data from the host computer 4, and shifts to a print preparation state.

In step S9, the carriage 10 is moved to the right, and in step S10, the stepping motor 6 is turned on.
_It is judged whether or not it has rotated ₂ steps. This n ₂ step is the number of steps for moving the carriage 10 to the edge of the sheet 30, and is set to 8 steps, for example.

After the carriage 10 is transferred as described above, the process proceeds to step S11 to start the printing operation.

As described above, the carriage 10 is stopped at the home position only by the control of the stepping motor 6 without using the home position detector as in the conventional serial printer, and then the carriage 10 is moved to the paper edge. Printing operation can be started. Moreover, such a process can be performed at the time of resetting as well as when the power is turned on, and can be promptly executed.

When the stepping motor 6 is stepped out, noise may increase at the time of stepping out, but this can be avoided by using a stepping motor having a small torque as the motor for moving the carriage. In particular, it is effective for a thermal printer, an inkjet printer, and the like, and is suitable for a printer having a narrow print paper width and a narrow carriage transfer area, that is, a printer for issuing receipts having a short step out time.

[0033]

As described above, according to the present invention,
The home position of the print head can be determined without using the home position detector, and the home position detector can be omitted and home position detection using the home position detector and its control are not required, and the configuration can be simplified. it can.

If a frame is used as the stop member, the structure can be further simplified.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a home position determining method for a serial printer according to the present invention.

FIG. 2 is a perspective view showing a print head transfer mechanism in the serial printer shown in FIG.

FIG. 3 is a diagram showing a print head transfer area in the serial printer shown in FIG.

FIG. 4 is a flowchart showing an embodiment of a home position determining method for a serial printer according to the present invention.

FIG. 5 is a perspective view showing a print head transfer mechanism in a conventional serial printer.

FIG. 6 is a block diagram showing an overall configuration of a conventional serial printer.

FIG. 7 is a flowchart showing a home position determining method for a serial printer using a conventional home position detector.

[Explanation of symbols]

 2 control section (control means) 6 stepping motor (carriage mechanism) 8 print head 10 carriage 14 frame (stop member)

Claims (2)

[Claims] 1. A carriage equipped with a print head, a carriage mechanism for transporting the carriage by a stepping motor, and a control means for controlling the rotation of the stepping motor, for rotating the stepping motor forward or backward. The carriage is caused to collide with a stop member to stop the carriage, and a position where the stepping motor is rotated from the stop position by a preset number of steps is set as a home position of the print head. Position determination method. 2. The home position determining method for a serial printer according to claim 1, wherein a frame of the serial printer is used as the stop member.