| 摘要 |
PURPOSE:To perform the alteration of magnification toward sub-scanning simply, by constituting the sub-scanning drive motor with a plurality of stepping motors SMs of which rotary shafts are linked and which rotate in different speeds, and by selectively driving one of them. CONSTITUTION:The rotary shafts of SMs 6, 8 are linked with the universal joint 7. The ratio of rotary angles of SMs 6, 8 is, for example, taken as the ratio of paper width of A3 and A4 sizes, and the phase shifter 9 having drive clock pulse forms a series of phase pulse, which is fed to the motor drivers MDs 10, 11. The drive pulse output reference signal +V is fed to MD 10, 11 selectively via the relay contact piece AC, and when the signal +V is incoming to MDs 10, 11, they feed the drive pulse amplifying the phase pulse to SMs 6, 8. When power is given to the relay coil AL, SM8 is energized and when the coil AL is de-energized, SM6 is activated, allowing the picture corresponding to the paper width respectively. |
