Overload pressure top for machine tools has piston radially spaced from walls inside a cylinder and bearing sealed against cylinder lid to transfer forces when maximum pressure force is exceeded

摘要

The overload pressure top is formed by a piston (4) mounted inside a cylinder (1) radially spaced from the cylinder wall inside the flow of the reforming force so as to transfer axial forces through bearing sealed at one end against the cylinder lid (5). Apart from conventional seals a higher-strength metal sealing ring (6) can be used which is sealed on one side and follows the piston movement over a short route. Nitrogen is used as the pressurised gas. When the maximum force is exceeded the piston is released from its seat and breaks the force flow. The space (20) formed between the top of the piston and the seal forms a sensor chamber in active fluid connection with further similar chambers of other pressure pots.