JPH0361048A - Dot impact-type printer - Google Patents

Abstract

PURPOSE:To enhance a throughput even if the number of dots to be printed is large by a method wherein the temperature of a printing head is measured, a printing dot number limit value corresponding to the measured temperature is compared with the total number of dots to be printed in each printing line, in accordance with the compared result the number of carriage feed actions in each printing line is determined, and printing is performed by a printing head. CONSTITUTION:A thermistor 2 for measuring the temperature of a printing head 1 is provided. A dot number limit value calculation circuit 3 calculates a printing dot number limit value determined corresponding to the measured result which is obtained by numerically converting the measured result of the thermistor 2 by an internal A/D converter. A dot number counting circuit 4 counts the total number of dots to be printed in each printing line from dot data sent from a host circuit prior to printing and outputs a printing dot number count value. A comparison circuit 5 compares the printing dot number count value with the printing dot number limit value. A control circuit 6 controls a drive circuit 7 in accordance with the compared result of the comparison circuit 5; printing is respectively conducted with one or two carriage feed actions if the printing dot number count value is smaller or larger than the printing dot number limit value. The drive circuit 7 actuates the printing head 1, a motor, and the like.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a dot impact printer.

・1. ~ vl [Prior Art] In general, in dot impact printers, the more dots to be printed, the more mold the print head generates, so if a large number of dots are printed in succession, the print head will heat up. Damage may occur.

In conventional dot impact printers, in order to prevent the print head from overheating, if the number of dots to be printed in a print (i) exceeds a fixed predetermined limit for the number of print dots, the print line is reprinted multiple times. Printing is performed by dividing the carriage feed operation into J: It was turned out.

[Problem to be solved by the invention]

In the conventional printer 1-inva 91~ type mentioned above,
Since the print driver number limit value is fixed, even if the print head temperature is low, if the number of dots in a print line exceeds the fixed value, it will be divided into multiple prints and the throughput will be low. There is a drawback.

The present invention has been made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide a dot-impact printer that improves throughput by 2 to 20% when the temperature of the print head is low.

[Means to solve the problem]

The dot impact printer of the present invention includes: a temperature measuring means for measuring the temperature of the print head; a limit value outputting means for outputting a print dot number limit value determined in response to the measurement result of the temperature measuring means; A counting means for outputting a printed dot count value by inputting the total number of dots to be printed in each print line as an argument prior to printing from dot data given to be printed; The control means determines the number of carriage feeding operations for each print line in accordance with the result of comparison with the limit value, and causes the print head to print.

[Effect]

The measuring means measures the temperature of the print head, and the control value outputting means outputs a print dot number limit value corresponding to the measured temperature. The control means determines the number of carriage feeding operations for each print line depending on whether the total number of dots to be printed in each print line is greater than the output limit value for the number of print dots.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the dot impact type printer of the present invention.

The print head is provided with a thermistor 2 as a temperature measuring means for measuring the humidity of the print head 1. The dot number limit value calculation circuit 3 converts the measurement result of the thermistor 2 into a numerical value using an internal A/D converter (not shown), and outputs a print dot number limit value determined in accordance with the digitized measurement result as a limit value output means. Calculated as That is, when the humidity of the print head 1 is high, the limit value for the number of print dots is set low, and when the humidity of the print head 1 is low, the limit value for the number of print dots is set high. As a specific example, a device configured such that when a numerical measurement result, which is temperature data, is entered into a ROM address, a limit value for the number of printed dots is output as output data can be used.3, The dot number counting circuit 4 is , the total number of dots to be printed in each print line is counted prior to printing from the dot data given for printing from a higher-level circuit (not shown), and a printed dot count count value is output. The comparison circuit 5 is
Compare the printed dot number count and the printed dot number limit value. Based on the comparison result of the comparator circuit 5, the control circuit 6 controls each printing line so that if the printed dot count is smaller than the printing dot number limit value, printing is performed once, and if it is larger, printing is performed by gear ridge feeding operation twice. The number of carriage feeding operations is determined, and the drive circuit 7 is controlled to operate the print bed 1 and a motor (not shown).

〔Effect of the invention〕

As explained above, the present invention determines the number of carriage feeding operations for each print line in accordance with the temperature of the print head, so that even if the number of dots to be printed is large, if the temperature of the print head is low, fewer Printing is performed using the carriage feed operation, which has the effect of improving throughput. Also, if the print head temperature is high, reduce the number of printing operations.
It is easy to use, and because it reduces the number of dots printed at one time, it also has the effect of preventing the temperature of the print head from rising too high.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the dot-in-back type printer of the present invention. DESCRIPTION OF SYMBOLS 1...Print head, 2...Thermistor, 3...Dot number limit value calculation times 1t, 4...Dot counting circuit, 5...Comparison circuit, 6...Control circuit, 7...・Drive circuit.

Claims (1)

[Scope of Claims] 1. Temperature measurement means for measuring the temperature of the print head; limit value output means for outputting a print dot number limit value determined in response to the measurement result of the temperature measurement means; a counting means for counting the total number of dots to be printed in each print line prior to printing from given dot data and outputting a printed dot count count; a print dot count and a print dot limit limit; A dot impact type printer, comprising: control means for determining the number of carriage feeding operations for each print line according to the results of comparing the numbers, and causing the print head to print.