Mirror image printing printhead

A print head dividing one line printing into a plural number of printing line blocks for one line printing to achieve time sharing printing block by block, said print head being connected to signal supply means composed of a CPU for serially inputting prints data for each of the printing line blocks and clock pulses in synchronization with the print data, there being a selected number of clock pulses for the print data for each of the printing line blocks, and said print head comprising:

• a print means for printing a pattern composed of successive parallel lines, each of said lines being composed of a plurality of dots in a row, in response to print data for each of said lines, said print means being divided into a plural number of print blocks, each associated with a respective one of the printing line blocks, one of said print blocks being a last print block and said print blocks being operated one at a time,
• a storage means for storing print data inputted by serial transfer from said signal supply means,
• a block detecting means for generating a block detect signal upon input of print data for one of said print blocks according to the selected number of clock pulses inputted in synchronization with the print data,
• a block selecting means for selecting the print blocks of the print means individually and in sequence and driving the selected one of said print blocks according to the block detect signal for one line of printing so that said last print block is selected after selection of all of said print blocks other than said last print block,
• a print data stop signal generating means for transmitting a print data stop signal to said signal supply means to stop transfer of print data from said signal supply means according to the block detect signal, a print data request signal generating means for outwardly transmitting a print data request signal after printing is performed by each of said print blocks of the print means to initiate transfer of print data from said signal supply means, and
• a latch circuit for receiving print data for one of said print blocks which is being selected by said block selecting means, the print data being parallel-transferred from the storage means, and storing the print data therein, wherein the latch circuit receives print data for the selected one of said print blocks by parallel transfer when the block detecting means detects input of print data for the selected one of said print blocks, and the storage means receives print data for the one of said print blocks to be selected in sequence by said block selecting means upon completion of the parallel transfer of the print data for said selected one of said print blocks, wherein
• after input of print data from the latch circuit to the last one of said print blocks selected by said block selecting means for performing printing on one line, the block detecting means receives a group of clock pulses containing the selected number of clock pulses from the signal supply means, and
• the block selecting means is provided with a block number counting means for counting the block select signals from the block detecting means so that the block detecting means and the block selecting means will be reset to initial states whenever the block number counting means counts a number of blocks which is one greater than the number of print blocks for printing one line.

A print head dividing one line printing into a plurality of printing line blocks to achieve time sharing printing block by block, said print head being connected to signal supply means composed of a CPU for serially inputting print data for each of the printing line blocks and clock pulses in synchronization with the print data, there being a selected number of clock pulses for the print data for each of the printing line blocks, and said print head comprising:

• a print means for printing a pattern composed of successive parallel lines, each line being composed of a plurality of dots in a row, in response to print data for each line, said print means being divided into a plurality of print blocks, each associated with a respective one of the printing line blocks, and said print blocks being operated one at a time,
• a storage means for storing print data inputted by serial transfer from said signal supply means,
• a block detecting means for generating a block detect signal upon input of print data for one of said print blocks according to the selected number of clock pules inputted in synchronization with the print data,
• a block selecting mean for selecting the print blocks of the print means individually and in sequence and driving the selected one of said print blocks according to the block detect signal, wherein
• the storage means has a plurality of serially connected data storage stages including a first stage and a last stage, for storing print data in a selected one of a first order from the first stage to the last stage and a second order from the last stage to the first stage,
• the print blocks are disposed in the print means in a row which is parallel to the parallel lines of the pattern to be printed and which has first and second ends,
• said print head further comprises print data order selecting means for selecting either one of the first order and second order of storing print data in the storage means,
• said block selecting means comprise block order selecting means for selecting the print blocks of the print means in a selected one of a first order from the first end to the second end of the row and a second order from the second end to the first end of the row,
• said print head further comprises mode selecting means for controlling the print data order selecting means and the block order selecting means in a manner to effect printing of the pattern in a selected one of first and second modes, with the pattern in the second mode being a mirror image of the pattern in the first mode, and
• the block order selecting means comprises an up-down counter having a count direction which is switched over between increment and decrement under control of the mode selecting means.