PURPOSE: To prevent offsetting of the dots of various colors during color recording by detecting the difference between the speed at which a driven shaft to be rotated by a drive shaft via a friction member rotates during the first turn, and the speed at which the driven shaft rotates during the second or third turn, and increasing or decreasing the speed of rotation of the driven shaft according to the difference.
CONSTITUTION: When a rotation transmitting drive gear is used in a printer in which the motor shaft 2 of a stepping motor 1 is transmitted to a driven pulley 4 via a magnetic idler 3 serving as a friction member so that color printing is performed by means of a drum shaft 11 mounted on the center shaft 4a of the driven pulley 4, rotation of the driven pulley 4 is detected by an encoder 5 and pulses output from the encoder 5 are input to a control circuit 6, and the control circuit 6 outputs changed drive frequencies to the stepping motor 1. In that case, data about the speed at which the drum shaft 11 rotates during the first turn (for the first color) are stored on memory and are compared with the speeds of rotation of the shaft 11 during the second and third turns, and the speed of rotation of the drum shaft 11 is increased or decreased according to the deviation among them.
TAKEMOTO TAKESHI
KIMURA TAKASHI
SHINGYOUCHI MITSURU
