| 摘要 |
A drive and control arrangement for a mechanical eccentric press is disclosed. The arrangement includes a direct current electric motor connected to a reduction gear mechanism. An output shaft of the reduction gear mechanism is coupled to an eccentric such that the eccentric rotates with the shaft about a common axis. A connecting rod of the press is connected to the eccentric for pivotal movement about an axis parallel to and offset from the common axis of the shaft and eccentric. The arrangement includes a limit switch that is operated by a cam element adjustably mounted on the eccentric. An electronic control device is included and has a starter unit for supplying electric current to the motor, and a braking unit for short-circuiting the armature of the motor through a resistance in order to brake the motor and the press. The braking unit is actuated by the limit switch a predetermined period after the connecting rod has moved through its bottom dead center position. A timing device is included to initiate braking of the electric motor and press after a predetermined period when the limit switch fails to interrupt the supply of electric current to the motor or when the connecting rod becomes blocked in the bottom dead center position. The arrangement includes circuit elements which permit the speed of the electric motor to be reduced, and which permit the electric motor and press to be stopped at any point during the press cycle.
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