| 摘要 |
<p>HAMMER BANK MOVE CONTROL SYSTEM A hammer bank system for use in a high speed impact printer includes a movable hammer bank in which the hammer spacing is twice the character spacing. A hammer bank controller is used to move the entire hammer bank between two selected hammer bank positions. In one hammer bank position, the hammers are aligned with odd character positions and in the other hammer bank position, the hammers are aligned with the even character positions. The hammer bank controller in response to a move command signal from the printer logic section drives the hammer bank (in a velocity mode) from one of its positions to the other first at an increasing velocity, followed by a constant velocity, until the bank is at a selected distance from the desired position, at which time the hammer bank velocity is decreased to zero and the hammer bank is substantially at the desired position. The controller switches to a position mode in which a position signal is used in a position servo loop to lock the hammer bank at the desired position. In normal operation when the bank is switched to the position mode, a move complete signal is fed back to the printer logic section to terminate the move command signal. Positioning initialization circuitry is also included to automatically drive the hammer bank to one of its desired positions.</p> |
