| 摘要 |
PURPOSE:To obtain a highly reliable exhaust gas controlling device for a hydraulic machine by being constituted by a detector for detecting a position of a moving part of an exhaust valve in itself and a device for issuing a command of exhaust valve-close exclusively or giving an alarm simultaneously. CONSTITUTION:A C-NC contact 101 of a position switch 23 for detecting a position where an exhaust valve is entirely closed is closed regardless of an operating condition of a main machine if the exhaust valve is opened even only slightly when constructed such that the exhaust valve is closed when an electromagnet is energyzed. As far as this condition is kept, a time limit relay 102 continues to count time. And, when a prescribed interval of time lapses, a time limit contact 103 is closed, an electromagnet 105 for a exhaust valve close-operation is energyzed exclusively to permit the exhaust valve to be closed irrespective of an original exhaust valve-close controlling circuit. Simultaneously, an alarm is issued by the other time limit close contact 104, and thereby it is possible to take a necessary measure even if the exhaust valve would no be closed. |
