Residual pressure exhaust air circuit and residual pressure exhaust valve

Abstract

[Object] To make it possible to detect, with a single pressure sensor, a malfunction of two solenoid valves for switching flow paths and to quickly and reliably exhaust residual pressure in an air device through a solenoid valve. [Solution] A residual pressure exhaust air circuitincludes: a main flow paththrough which air from an air sourceis supplied to an air cylinder; an exhaust flow paththrough which air in the air cylinderis exhausted; a first sensorfor detecting a malfunction of solenoid valves; a detection flow paththrough which air from the air sourceis supplied to the first sensor; and the two solenoid valvesthat switch communication states among the main flow path, the exhaust flow path, and the detection flow path. The two solenoid valvesare formed of two-position valves having first positionsat the time of OFF and second positionsat the time of ON and are synchronously ON/OFF controlled. When the two solenoid valvesdo not operate in synchronization with each other, the air from the air sourceis supplied to the first sensorto detect a malfunction of the two solenoid valves, and at the same time, the air in the air cylinderis exhausted through the solenoid valve