JP2502448B2 - Printer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus capable of returning to a home position by moving printing means.

[0002]

2. Description of the Related Art A serial printer installed in a printing device, such as a calculator with a printer, has a mechanical printer having a printing type ring, a thermal printer for recording on thermal paper, and a small nozzle for ejecting ink. There are ink jet printers, etc. that print on plain paper. In all of these methods, a print head for printing linearly reciprocates left and right on a journal paper, which is a recording paper, to perform printing. In such a serial printer, a reset operation for returning the print head to the home position is performed. For this reason, it has a detection means for detecting whether or not the print head is located at the home position, and returns the print head to the home position which is the reference position each time printing is performed by this detection signal. I am letting you. However, there is a problem in that it is necessary to provide detection means.

[0003]

[Object] In view of the above points, an object of the present invention is to position the printing unit at the home position position while reducing the useless control such as driving the printing unit even when the printing unit is in the immovable state. An object is to provide a printing device.

[0004]

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

FIG. 1 is an external view of a printing apparatus as an example of the present invention, FIG. 2 is a block diagram of an embodiment for realizing the present invention, and FIG. 3 is a flow chart of an example of the present invention.

In the external view of FIG. 1, KB is a numerical key, a function key, a paper feed key according to the present invention,

[0007]

[Outside 1] Is a keyboard portion arranged as shown in the figure. DIS
Is a display device for displaying and outputting input data and calculation results. The TS section stores a serial printer for printing out the above data and calculation results.

FIG. 2 is a block diagram of the present invention.
The part is the same keyboard part as in FIG. 1, and the CPU is usually 1
It is composed of a chip LSI and is composed of the following.
The IC is a key input control unit, which outputs a key signal to the keyboard unit KB to determine the operated key. Reference numeral U denotes an arithmetic control unit that performs arithmetic operations such as addition, subtraction, multiplication and division, paper feed, and reset operation by operating any key of the keyboard unit KB. RA is a RAM (random access memory) that stores numerical data, flags, counters, and the like. The RO stores a control program corresponding to each key operation of the keyboard portion KB, and the RO for which calculation and output control are performed based on the program.
This is the M (Read Only Memory) section.

DIS is a display unit for displaying and outputting numerical data and the like in response to a signal from the arithmetic control unit U.

The printing section PR may be mechanical, thermal, or ink jet, and will be described as an example of a thermal printing section. A print head TH is a print head, for example, a thermal head, and the heating elements are arranged in one row of 7 dots. By applying an electric current to the thermal head, dots are printed on the thermal paper which is a recording paper.

M is a pulse motor for reciprocating the thermal head TH to the left and right on the recording paper, and the head movable area of the highest digit from the home position of the lowest digit is fixed at 20 digits. There is. Further, the head is mechanically reciprocally moved from the home position by the upper four digits, so that the recording paper for one line is fed (detailed description is omitted). HC is a head control circuit for driving the thermal head TH, and is composed of a character generator that converts a 6-bit data code sent from the arithmetic control circuit unit U into a print pattern. MC is a motor control circuit for controlling the pulse motor M, which generates pulses one pulse at a time to move the thermal head and TH to the left or right. Since one digit consists of 7 pulses, 7 pulses are output by the movement control for one digit. MD and HD are drive circuit units for amplifying current by signals from the control circuits MC and HC to drive the pulse motor M and the thermal head TH.

Next, the operation of the present invention configured as described above will be described with reference to the flow chart of FIG.

In this embodiment, the home position detecting means is abolished in order to simplify the printing section, and the print head is returned to the home position by a so-called step out method. In this step-out method, the number of digits moved from the home position of the printing unit to the upper digit direction is, for example, 20.
In the case of a digit, first, the print head is moved in the direction of the upper digit by 20 digits, and then is moved by 20 digits in the direction of the home position again to return to the home position. For example, if the print head is stopped at the center position from the lower digit to the tenth digit, moving the first 20 digits to the upper digit will cause the digit to become the uppermost digit and the remaining 10 digits. The movement control is in a so-called step-out state while the print head is stopped at the highest digit. After that, the print head is returned to the home position by moving it toward the home position by 20 digits.

In FIG. 3, in step 1, "other key is ON.
Is a command to determine whether or not any key other than the paper feed (PF) key is operated. If a numeric key or a function key is operated, the result is YES. A key process corresponding to each key operated in step 2 is executed. Needless to say, various data input from the key may be input from an external device. If the above keys have not been operated, the process proceeds to NO, and it is determined whether or not the "PF key" paper feed key in step 3 is pressed. If the PF key is pressed, Y
Proceed to ES, and in step 4 "F _FP = 1", the PF key starts to be pressed and the flag F _FP is determined. If the PF key now starts to be pressed, the F _FP is reset, so the direction is NO Proceeding to step 5, the process of "moving to TH 20 digit, upper digit" in step 5 is executed. This is to move the thermal TH to the highest digit, and the motor control circuit MC
Therefore, 20 × 7 = 140 pulses and pulses are output.
By this process, the thermal head TH is moved to the most significant digit regardless of the position where it is stopped. Next, in step 6, the pulse motor is reversely rotated by 140 pulses by the processing of "Move to TH 20 digit, lower digit" to return the thermal head to the home position. The processes of steps 5 and 6 are so-called reset operations. 1 at the same time
A line feed operation is executed. Next, in step 7, “1 →
"F _FP ", the flag F _FP is set to "1" and PF
It is recorded that the key is not pressed. After that, the process of step 1 is executed again, and if the PF key is continuously pressed, the process proceeds to NO, and in the determination of the next step, YE
Going to S, the flag F _{FP in} step 4 is judged, and since it is set to "1" in step 7 above, it proceeds to YES this time, without performing the reset operation of the previous steps 5 and 6. First, in step 8, the head is moved to the upper 4 digits and then in step 9, the head is moved to the lower 4 digits and returned to the home position. This step 8,
By the processing of 9, the paper feed control for one line is executed. After that, the counter CT is cleared in step 10 and the process jumps to step 1 again, and while the PF key is continuously pressed, the steps 1 → 3 → 4 → 8 → 9 → 10 → 1 are repeated as in the previous time and the paper is repeated. The feeding continues. After that, when the PF key is released, the process proceeds to NO in step 3, and then the determination command of "F _FP = 1" in step 11 is executed. Right now, F _FP is still set to "1", so YE
Proceeding to S, the "CT + 1 → CT" command of step 12 is executed. This is a process of adding “1” to the CT counter, and 0 + 1 is executed and the CT counter becomes 1, and in the next step 13, it is judged whether the CT counter is 100 or not, and the CT counter becomes 100. 3 → 11 → 12 → 13 → 1 is repeated.
The processing time of steps 1 to 13 is set to 400 μS (microsecond).
When it is repeated, 100 × 400 μS = 40 mS (millisecond). When the PF key is released for 40 mS, the process proceeds to YES in step 13, the CT counter is cleared to “0” in step 14, and the flag F is detected in step 15. _FP
Is reset to "0". When the PF key is pressed again by resetting the F _FP , the process is performed in the order of steps 1 → 3 → 4 → 5 → 6 → 7 as described above, and the reset operation is first performed, and then the Step 1 →
The repeating process of 3 → 4 → 8 → 9 → 10 → 1 is executed to feed the paper.

If the PF key is released, steps 1 → 3
If the repeat count process of → 11 → 12 → 13 → 1 is performed and the key is pressed again before the count number reaches 100, the F _{FP is} still “1” in step 1 → 3 → 4. As it is, proceed to YES and go to the next step 8
The line feed operation of 9 is performed and the count CT of step 10 is cleared to the initial "0". As mentioned above, the instantaneous OFF state of the PF key of 40 mS or less is the key-specific OFF state.
Bounce is detected, and at that time, processing is performed to prevent the reset operation from being executed.

As is clear from the above explanation of the operation, even when the print head is out of step and is displaced from the home position, various data during calculation can be stored without adding a key such as a reset key. By providing the paper feed key with a reset function that does not clear, an inexpensive and convenient printing device can be provided.

[0017]

As described above in detail, according to the present invention, it is possible to position the printing means at the home position by reducing unnecessary control such as driving the printing means despite the immovable state. It is possible to provide a printing device capable of performing the above.

[Brief description of drawings]

FIG. 1 is an external view of a printing apparatus that is an example of the present invention,

FIG. 2 is a block diagram showing an example of the present invention,

FIG. 3 is a flow chart according to the present invention.

[Explanation of symbols]

 KB Keyboard part CPU 1 chip LSI U Operation control part RO ROM part TH Thermal head M Pulse motor

Claims (1)

(57) [Claims] 1. A printing unit for performing relative movement between a home position position relative to a sheet and an uppermost position and printing data to be printed, and the home position position. Instructing means for instructing to return the printing means, and when instructed by the instructing means, the home position and the uppermost position in the uppermost position direction regardless of the current position of the printing means. And a control for controlling the drive of the printing means so as to move the printing means so as to move in the home position position direction from the uppermost position moved based on the control. And a printing device.