| 摘要 |
PROBLEM TO BE SOLVED: To improve transference accuracy after switching the rotational direction of a transfer roller from forward and reverse in the wiping operation by controlling the transfer roller in such a manner that the amount of the reverse drive is divided into two or more in terms of the number of drive times, and then the forward drive is initiated, when the transfer roller is driven reversely in the direction opposite to a direction in which a sheet material is transferred at the time of its transfer, and after that, is normally driven to its position before the reverse drive. SOLUTION: When an instruction for wiping is received after a normal sheet transfer upto a position (a), an LF motor is reversely driven by 10 pulses and a carriage motor is driven at a position (b) to shift a carriage carrying a recording head for a wiping operation. After this wiping operation, the LF motor is reversely driven by further 6 pulses to a position (c), so that the total amount of reverse drives is equal to the integral multiple of 4 pulses or a single period of the LF motor. Thereafter, the total amount of the reverse drives of 16 pulses is divided in two, i.e., 8 pulses each, and the LF motor is normally driven twice, each time by 8 pulses to drive the motor back to the position (a), before the reverse drive and the forward sheet transfer is resumed. Thus the transference accuracy of a transfer roller after switching of its rotation from forward to reverse or vice versa is improved and thereby, a high quality image is obtained. |
