| 摘要 |
In the method of controlling a process for moving a part ( 20 ) by an electric motor ( 12 ) against an end stop, pinching events are detected by monitoring a motor operating variable, such as a motor rpm, and if pinching is detected the motor ( 12 ) is stopped and/or reversed. The electric power triggering the motor ( 12 ) at the start of and during a startup phase while system slack is taken up is controlled so that it is constant and lower than the power triggering the motor in an ensuing operating phase ( 54 ) in which the part ( 20 ) moves. Preferably power during the startup phase is reduced to power values that are just barely enough to move the motor while system slack is taken up. In a preferred embodiment the applied motor voltage is reduced and controlled by a power end stage that includes a bipolar transistor or a field effect transistor. |
