| 摘要 |
An apparatus for controlling ribbon feed includes a rotatable supply roll (10) and a rotatable take-up roll (12). A first electric motor (74) is provided for driving the take-up roll (12) in a first direction of rotation and a second electric motor (72) drives the supply roll (10) in an opposite direction of rotation. A ribbon tension sensing means (76, 78, 112) is provided for sensing when the part of the ribbon (24) between the supply roll (10) and the take-up roll (12) is in a slack condition and operating means (110) is controlled by the ribbon tension sensing means (76, 78, 112) for operating the second electric motor (72) to drive the supply roll (10) in the opposite direction to take up slack in the ribbon (24). |
