| 摘要 |
In order to drive gates, in addition to the elements which carry out the work, such as circulating chains etc., electrical drive units are known in which an electric motor, a transmission unit and further control elements are accommodated inside a housing which consists of a baseplate and housing and is screwed to the cover etc.. In this case, it is also known for the limit switches, for the approach to the limit positions of the gate, to be accommodated inside the housing. In order additionally to define points at which the moving door actually changes over from high speed to slow speed, time-dependent controllers were used in the past. In order to increase the adjustment capability and the ease of repair, it is intended to implement all four positions by electromechanical limit switches. To this end, in addition to the previously known two limit switches which were mounted on the baseplate (1) in addition to longitudinally moving control elements, two such limit switches are also accommodated in a suitable depression (27) in the baseplate (1) under the control elements and are held in position by retaining parts which are mounted and screwed on with the aid of the two other limit switches. <IMAGE> |
