Coal-cutting plane, hydraulic travel limit mechanism - uses pressure in end stop chamber to cause switch to break current supply

摘要

Automatic circuit devices for switching off drive units, and hydraulic attenuators to limit travel before reaching the point of reversal for the draw chain, are provided for a coal-extracting machine, esp. coal plane, in a mine. A switching element is located at a prescribed distance from the reversal point. A hydraulically damped plane end stop has a working chamber with throttle serving as outflow opening. A switch, activated by pressure in this chamber, interrupts current supply to the plane drive, at a predetermined pressure level. The plane is quickly and reliably switched off, while entry into a defined end setting is guaranteed.