| 摘要 |
A printing apparatus especially for a cash register has printing wheels mounted on a shaft with a spring pressed friction detent means between the shaft and each wheel so that the wheels are positively driven but can overrun the detent means when they are stopped in their printing positions while having residual frictional engagement; the shaft rotating through only a part revolution then remaining stationary during printing and finally driving in rotating through only a part revolution then remaining stationary during printing and reverse to return the wheels to their starting positions. |
