Patent ID: 8419304

Claim:
A printer, comprising: a DC motor, a paper feeding unit including a paper feeding roller that uses the DC motor as the driving source thereof, a printing mechanism unit, for printing, using the printing mechanism unit, onto paper that is advanced by a specific amount by the paper feeding unit, an encoder for outputting a pulse signal for speed control of the DC motor according to the rotation of the DC motor, a pulse forming region, on the periphery of an encoder plate, for forming pulse signals, and a uniform spacing region, a first non-uniform spacing region and a second non-uniform spacing region provided within the pulse forming region such that said first non-uniform region and said second non-uniform spacing include only those portions of the pulse forming region where spacing changes in such a way as to differ in width from the spacing provided in the uniform spacing region of the pulse forming region, wherein the first non-uniform spacing region having spacing wider than the uniform spacing within the uniform spacing region so that the number of pulse signals outputted is fewer than the number of pulses signals outputted by the uniform spacing region when rotating at a constant speed; and the second non-uniform spacing region having spacing narrower than the uniform spacing within the uniform spacing region so that the number of pulse signals outputted is greater than the number of pulses signals outputted by the uniform spacing region at a constant speed under the same rotation conditions.