THREE-WAY VALVE WITH TOP END-STOP ON THE AIR PATHWAY

摘要

PURPOSE: A three-way valve with an upper end stop arranged in an air passage is provided to inspect the integrity of mechanically continued operation in all paths, and to diagnose the fault of the paths with a detecting unit. CONSTITUTION: A three-way valve comprises control units(7-11) for two gates(5,6), and first and second driving units(12,13,15). The first and second driving units are controlled by the control units, and move one of the two gates to one of first and second positions. The control units and the first and second driving units operate to make the two gates simultaneously reach the second position in a normal operation mode. The three-way valve comprises a maximum displacement end stop(31) for one of the driving units. The end stop blocks the driving units when one of the gates corresponding to the end stop is positioned at the second position. The valve comprises a unit for detecting whether or not the other gate moves over the second position.