| 摘要 |
A door closing switch (50) is operated by a key (52) and an electronic controller (46) switches on the motor (14) to drive the reversible rotary pump (12). Simultaneously a 2-way, 2-position regulating valve (41) is put into its operating position, in which a vent line (49) is blocked. The rotary pump sucks air from a pneumatic system (16,18,22,32) and pulls a piston (34) with a handle (36) downwards and locking by means of a lock attached to the piston. The position is communicated from a pressure switch (42) over an answer back line (44) of the electronic control to switch of the motor. When the pressure switch (42) monitoring the pressure of the system switches off the pump (12), the valve (41) takes up its alternative working position, the system (16,18,22,32) is thereby opened to atmosphere. The handle (36) can then be operated at once. |
