Page 114 - PNEUMATIC SYSTEM INSTRUMENT

QUESTION 2

A door of public vehicle and a working operation.

Working principle of the diagram

 This circuit is using two units 3/2-way valve push button to represent

ON and OFF button connected to 5/2-way valve. 5/2-way valve

connected to double acting cylinder to push the door open or retract the

door to closed.

 The extension path of a double acting cylinder is activated by control

valve (1), while retraction is governed by control valve (2)

 Control valve (3), on the other hand, maintains the position of the

cylinder by maintaining its own position.

 Control valve (3) will be changed only when one of the manual control

valves is pushed.

 If both control valves (1) and (2) are operated at the same time, control

valve (3) will be subjected to same pressure and will remain in its

original position.

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