JPH07256994A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To reduce the load of a CPU by a method wherein the judgement of whether the execution of the retrieval of non-printing region from print data and ribbon saving function is made or not is processed by means of hardware configuration. CONSTITUTION:A printer consists of an OR circuit 21, which yields output at high level when even one datum requiring printing is present in one line print data supplied, and a flip-flop 22. An output at low level yielded from the flip-flop 22 is counted every one line print data and the counting is cleared by the output at high level. yielded from the flip-flop 22. Further, a ribbon controlling circuit consisting of a counter 23, which outputs a count-over signal when the counted value exceeds L, is provided and is supplied with one line print data read by a pre-read pointer for saving ribbon, which advances one line print data actually used for printing by the set number of lines L, by a CPU.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer having a ribbon save function for saving consumption of an ink ribbon in a non-printing area.

[0002]

2. Description of the Related Art In a thermal transfer printer that prints on paper using an ink ribbon, if the thermal head is kept in contact with the platen via the ink ribbon and the paper even in the non-printing area, the paper The ink ribbon is also conveyed along with the conveyance, and is taken up by the take-up roller that takes up the printed ink ribbon.

[0003] Once wound up on the winding roller in this manner, it is not used again for printing again, so that the area of the ink ribbon conveyed along with the conveyance of the non-printing area is wasted. was there.

Therefore, some conventional thermal transfer printers have a ribbon save function. (See Japanese Patent Publication No. 62-38153 and Japanese Patent Publication No. 62-38154)
For example, all print data is stored in the print memory, and a non-print area is searched from the print data stored in this print memory. When the searched non-printing area is more than a certain number of lines and when the tip of the non-printing area reaches the print position of the thermal head, the thermal head is moved to the up position away from the platen and wound. The rotation of the take-up roller is stopped to stop the feeding of the ink ribbon, and when the non-printing area passes and becomes the printing area, the thermal head is moved to the down position where it contacts the platen via the ink ribbon and the paper. , Start printing again. The non-print area is searched from the print data stored in the print memory described above, and whether or not the non-print area is equal to or greater than the preset number of lines (print length), that is, whether to execute the ribbon save function. It is C to judge
PU (central process-ing unit), ROM (read only
This was due to the software processing of the control unit composed of memory) and RAM (random access memory).

[0005]

As described above, in the conventional thermal transfer printer having the ribbon save function, the print data is not printed by the software processing of the control unit composed of the CPU, ROM, RAM and the like. I searched the area and determined whether the number of lines (printing length) in the non-printed area was the length to perform ribbon save. However, this search and determination process takes time, which is a burden to the CPU. There was a problem.

Therefore, according to the present invention, the retrieval of the non-printing area from the print data and the judgment as to whether or not to execute the ribbon save function can be processed by the hardware configuration.
An object of the present invention is to provide a thermal transfer printer that can reduce the burden on U.

[0007]

According to the present invention, when the number of lines in the non-printing area in the print data exceeds a preset number of lines, the thermal head is moved from the platen to the non-printing area in the non-printing area. In a thermal transfer printer that has a ribbon save function that moves the printer to a separate up position and stops the ink ribbon transport, the print data memory that stores print data and the line print data that is actually used for printing from this print data memory. The print data pre-reading means for reading the line print data in advance of the set number of lines, the OR circuit for inputting the line print data read by the print data pre-reading means, and the output of the OR circuit for printing one line The count is updated when the data is continuously low and the output of the OR circuit is high. When this happens, the counter is cleared, and a counter that outputs a countover signal when the count value exceeds a preset value, and the thermal head is moved to the up position by the countover signal from this counter to convey the ink ribbon. Ribbon save function executing means for stopping the ribbon save and ribbon save canceling means for canceling the ribbon save by the ribbon save function executing means based on the count clear of the counter after the output of the countover signal. is there.

[0008]

In the present invention having such a structure, the print data is stored in the print data memory.

The print data pre-reading means reads the line print data from the print data memory in advance of the line print data actually used for printing by the number of lines preset to execute the ribbon save function. .

The read line print data is input to the OR circuit. If the print data includes 1 (high level) data for printing even one, the output of the OR circuit becomes high level. Therefore, the output of the OR circuit becomes low level only when all the data are 0 (low level).

When the output of the OR circuit is continuously at the low level for the print data of one line, the count value of the counter is updated, and when the output of the OR circuit becomes the high level, the count value of the counter is cleared. .

When the count value of the counter exceeds a preset value, the counter outputs a countover signal, and the ribbon save function executing means moves the thermal head to the up position by the countover signal. Then, the ribbon save is performed to stop the ink ribbon conveyance.

Further, when the output of the OR circuit becomes high level after the output of the count-over signal, the count value of the counter is cleared and the ribbon save canceling means executes the ribbon save function executing means based on the count clear. Ribbon save is canceled.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a circuit configuration of essential parts of a thermal transfer printer to which the present invention is applied.

Reference numeral 1 denotes a CPU (centr that constitutes the main body of the control unit.
al processing unit).

A ROM (read only memory) 2 in which program data for processing performed by the CPU 1 is stored, the CP
RAM (random access memory) 3 in which areas of various memories used when U1 performs processing are formed, print memory 4 as print data memory for storing print data,
The communication interfaces 5 connected to the host computer via lines are connected to each other via a system bus 6.

The CPU 1 is connected to the system bus 6
A head controller 8 for controlling the thermal head 7, a paper feed motor controller 10 for controlling a paper feed motor 9 for carrying a sheet, and a ribbon feed motor for controlling a ribbon feed motor 11 for carrying an ink ribbon. Controller 12, ribbon save control circuit 13,
It is connected to a solenoid drive circuit 15 which drives a solenoid 14 for moving the thermal head 7 between an up position and a down position.

The ribbon save control circuit 13 uses the C
It is determined by the PU 1 whether or not the line print data prefetched from the print memory 4 is the non-print data, and when the number of lines in the non-print area where the non-print data continues is equal to or more than the preset number of lines. A control signal indicating execution of ribbon save is directly output to the ribbon feed motor controller 12 and the solenoid drive circuit 15 without passing through the system bus 6.

As the print data pre-reading means, the CPU 1 reads the 1-line print data to be actually used for printing based on the program data stored in the ROM 2 when the 1-line print data is read from the 1-line print data. The ribbon save prefetch pointer reads the preceding 1-line print data by the number of lines in the non-printing area for executing the ribbon save, and supplies the preceding 1-line print data to the ribbon save control circuit 13.

FIG. 2 shows a circuit configuration of a main part of the ribbon save control circuit 13.

The ribbon save control circuit 13 is mainly composed of
An OR circuit 21 having 17 input terminals (for example, it may be composed of eight OR circuits having two input terminals and one OR circuit having three input terminals) and a flip-flop circuit 22.
And a counter 23 that outputs a count-over signal when counting a preset count number.

The 17 input terminals of the OR circuit 21 are
Data bus (D0 to D15) of the system bus 6
) Is connected to the Q output terminal of the flip-flop circuit 22. The output terminal is connected to the D (data) input terminal of the flip-flop circuit 22.

To the CL (clock) input terminal of the flip-flop circuit 22, a 1-line CLK (clock) signal for generating a timing for the CPU 1 to read from the print memory 4 for each line of print data is input. The R (reset) input terminal is adapted to receive a RESET (reset) signal at the time of line start for generating the timing of starting reading for reading the first one-line print data from the print memory 4. There is. As described above, the Q output terminal is connected to one input terminal of the OR circuit 21, and is also connected to an input terminal to which the data counted by the counter 23 is input. It is also connected to the input terminal that clears the count value.

The 1-line CLK signal is inputted to an input terminal for generating a timing for taking in the data of the counter 23. The count-over signal output when the count value of the counter 23 becomes equal to or larger than the preset count value is output to the solenoid drive circuit 15 and the ribbon feed motor controller 12 as a control signal for executing the ribbon save function. It

That is, the solenoid drive circuit 15
When a count-over signal (high level signal) from the counter 23 is input, the solenoid 14 is driven to move the thermal head 7 to a platen (not shown).
When the count-over signal stops (becomes a low level signal) while moving to the up position away from, the solenoid 14 is driven to move the thermal head 7 to the down position where it contacts the platen. Further, the ribbon feed motor controller 12 uses the counter 2
When the countover signal from 3 is input, the rotation drive of the ribbon feed motor 11 is stopped and the ink ribbon (
When the count-over signal is stopped while the feeding of the ink ribbon (not shown) is stopped, the rotation of the ribbon feed motor 11 is restarted to start the feeding of the ink ribbon.

That is, the solenoid drive circuit 15 and the ribbon feed motor controller 12 constitute a ribbon save function executing means and a ribbon save canceling means.

In this embodiment having such a structure, C
Based on the program data stored in the ROM 2, the PU 1 first sets the ribbon save prefetch pointer to the start address of the print memory 4 and starts the prefetch of the 1-line print data. The one-line print data read by the ribbon save prefetch pointer is supplied to the ribbon save control circuit 13.

First, at the time of line start, the flip-flop circuit 22 is reset by the RESET signal, the 1-line CLK signal is input to the CL input terminal of the flip-flop circuit 22, and the first 1-line print data is ORed.
Input to the circuit 21.

The 1-line print data is composed of a plurality of bytes, and is sequentially input to the OR circuit 21 every 1 byte (16 bits) with the clock pulse of the 1-line CLK signal as the start timing.

Thereafter, each 1-line print data is input to the OR circuit 21 in synchronization with the timing when the 1-line CLK signal is input to the CL input terminal of the flip-flop circuit 22.

Here, if there is at least one printing data (1, high level) in one line print data, the Q output terminal of the OR circuit 21 becomes high level and the Q output terminal of the flip-flop circuit 22 becomes The high-level output is fed back to the input terminal of the OR circuit 21, so that the high-level output of the flip-flop circuit 22 self-registers until the 1-line CLK signal is input to the CL input terminal of the flip-flop circuit 22. Retained.

On the other hand, the high level output of the flip-flop circuit 22 clears the count value of the counter 23.
Therefore, the counter 23 does not output the countover signal.

Here, if there is no data to be printed in one line of print data, the output of the OR circuit 21 remains low level and the Q output terminal of the flip-flop circuit 22 remains low level. . At this time, the counter 23 receives one pulse of the one-line CLK signal and increments the count value by one.

As shown in FIG. 3, when the ribbon save prefetch pointer advances by the number of lines L preset as a non-printing area for carrying out the ribbon save function, the print read pointer is set to the head address of the print memory 4. Set to and printing starts. That is, the 1-line print data read by the print read pointer is supplied to the head controller 8 and output by the thermal head 7.

However, if the count value of the counter 23 has already reached the set line number L at this time, the counter 2
The count-over signal from 3 is the solenoid drive circuit 15
Also, the thermal head 7 is output to the ribbon feed motor controller 12, the thermal head 7 is moved to the up position, and the ink ribbon is not conveyed, so that printing is not performed.

Further, the 1-line print data is read by the print read pointer, the read 1-line print data is supplied to the head controller 8, and the 1-line print data is read by the ribbon save pre-read pointer to read the ribbon save control circuit. When it is supplied to 13, the printing read pointer and the ribbon save prefetch pointer are moved by a fixed set number of lines L and are read by each pointer, as indicated by a dashed arrow in FIG. The 1-line print data is supplied to the head controller 8 and the ribbon save control circuit 13, respectively.

FIG. 4 shows a pre-read data signal (output of the Q output terminal of the flip-flop circuit 22 for the example of the print data signal which becomes high level when there is at least one print data in one line print data. Signal) and the output signal of the ribbon save control circuit 13 (the output signal of the counter 23, the countover signal is a low level signal).

The read-ahead data signal precedes the print data signal by the set line number L. Therefore, the pre-read data signal becomes low level at time T1 which is earlier than the time T2 when the print data signal becomes low level (enters the non-printing area) by the time for reading the line print data for the set number of lines L.

When the low level state of the preread data signal continues for the time for reading the line print data for the set number of lines L, the counter 23 counts over, so that the output signal of the ribbon save control circuit 13 becomes low level. Then, the ribbon save function is implemented. That is,
The thermal head 7 is moved to the up position by the operation of the solenoid 14, the ribbon feed motor 11 is stopped, and the conveyance of the ink ribbon is stopped. At this time, the print data is also at a low level.

Thereafter, when the prefetch data signal becomes high level, the count of the counter 23 is cleared at this time T3, the countover signal is released, and the output signal of the ribbon save control circuit 13 becomes high level. The ribbon feed motor 11 starts driving to start the conveyance of the ink ribbon, and the operation of the solenoid 14 moves the thermal head 7 to the down position to enter the print standby state.

When the read data for the set number of lines L has elapsed and the print data becomes high level, the thermal head 7 resumes printing on the paper for each one-line print data read from the print memory 4. .

As described above, according to this embodiment, the OR circuit 21 and the flip-flop circuit 22 for outputting a high level if there is at least one data to be printed in the supplied 1-line print data, and this flip-flop. The low level output from the circuit 22 is counted for each line of print data, and the count is cleared by the high level output from the flip-flop circuit 22, and the count value is the set line number L.
A ribbon control circuit 13 including a counter 23 that outputs a count-over signal is provided in the above-described manner, and the 1-line print data actually used for printing by the CPU 1 is read by the ribbon-save read-ahead pointer that precedes the set line number L by 1 By supplying the line print data to the ribbon control circuit, the non-print area of the print data stored in the print memory 4 can be searched by the OR circuit 21 and the flip-flop circuit 22. The counter 23 can determine whether or not the ribbon save function can be executed for the character area. Therefore,
The CPU 1 only performs the process of supplying the 1-line print data read by the look-ahead pointer to the ribbon save control circuit 13, and does not need to search the non-print area and determine whether to execute the ribbon save function for the non-print area. So
The load on the CPU can be reduced.

In this embodiment, if the data to be printed is included in the 1-line print data read by the ribbon save prefetch pointer during the execution of the ribbon save function, the ribbon save function is immediately activated. However, the present invention is not limited to this. For example, a new counter may be provided and the ribbon save function may be released after reading the number of lines smaller than L. .

[0045]

As described above in detail, according to the present invention,
It is possible to provide a thermal transfer printer which can reduce the burden on the CPU because the hardware configuration can process the search for the non-printing area from the print data and the determination as to whether or not to execute the ribbon save function.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of essential parts of a thermal transfer printer according to an embodiment of the present invention.

FIG. 2 is a diagram showing a circuit configuration of a main part of a ribbon save control circuit of the thermal transfer printer of the embodiment.

FIG. 3 is a diagram showing a relationship between a print read pointer and a ribbon save prefetch pointer in a print memory of the thermal transfer printer of the embodiment.

FIG. 4 is a diagram showing timings of print data, preread data, and ribbon save control circuit output of the thermal transfer printer of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... CPU, 4 ... Printing memory, 7 ... Thermal head, 11 ... Ribbon feed motor, 12 ... Ribbon feed motor controller, 13 ... Ribbon save control circuit, 14 ... Solenoid, 15 ... Solenoid drive circuit, 21 ... OR circuit, 22 ... Flip-flop circuit, 23 ... Counter.

Claims (1)

[Claims] 1. When the number of lines in a non-printing area in the print data exceeds a preset number of lines, the thermal head is moved to an up position away from the platen in the non-printing area, In a thermal transfer printer that has a ribbon save function that stops ink ribbon transport, the print data memory that stores print data and the line data that is actually used for printing from this print data memory precedes the set number of lines. Print data pre-reading means for reading line print data, an OR circuit to which the line print data read by the print data pre-reading means is input, and the output of this OR circuit is continuously low level for one line of print data. When the output of the OR circuit becomes high level, the count is updated when A counter that outputs a countover signal when the count value exceeds a preset value, and the thermal head is moved to the up position by the countover signal from this counter, Ribbon save function executing means for carrying out ribbon save for stopping conveyance and ribbon save canceling means for canceling ribbon save by the ribbon save function executing means based on the count clear of the counter after the output of the count over signal. A thermal transfer printer characterized by being provided.