| 摘要 |
PURPOSE:To automatically prohibit the energizing of the heat generating element of a head to a degree corresponding to the reduced width amount of paper by detecting the width adjustment amount of the paper, by dividing a heat generating element group into a plurality of blocks and providing a circuit for prohibiting energizing at every block while providing a paper width detection apparatus performing input to said energizing prohibiting circuit. CONSTITUTION:In a fixed type head 1 comprising heat generating elements of 256 dots X 12 blocks, a binary data signal is inputted to each heat generating element and a strobes signal is inputted at a block unit. Now, in such a case that the width of paper 9 is set as shown by the drawing, when pin tractors 6, 7 are allowed to move a position coinciding with the pin perforations of the paper 9, a rotary encoder 5 detects the rotation amount of a screw rod 3 at this time to convert the same to an analogue signal which is, in turn, inputted to an energizing prohibiting circuit 8 as a prohibiting block selecting signal and the strobe signal to the blocks 2a, 2l at both ends of a max. printing width is cut off by a comparator 8a and the strobe signal to blocks 2b, 2k is cut off by a comparator 8b. |
