| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique that prevents the degradation and breakage of a sealing member and prevents the lowering of pump efficiency, even when used under an environment where the pressure in a low pressure region fluctuates.SOLUTION: In a fluid machine 10 disclosed in the present invention, a pump working chamber 30 and a through-hole 37 are formed along a drive shaft 22 in a housing 12. The through-hole is provided with a sealing member 38. The sealing member seals between an outer circumferential surface of the drive shaft and an inner circumferential surface of the through-hole, and sections an internal region 36 of the through-hole and the outside of the housing. In the housing, a communication path 35 for bringing the internal region into communication with a suction area 31 of a gear pump 20 is formed furthermore. The communication path includes an opening adjustment valve 60 to open and close the communication path. The opening adjustment valve opens the communication path when a difference between a pressure of the internal region and a reference pressure is higher than a predetermined value. The reference pressure is set in a pressure that is not fluctuated by the pressure in the communication path of the suction area side using the opening adjustment valve. |
