DEVICE FOR ABSORBING HYDRAULIC SURGE

摘要

PURPOSE:To drastically reduce frictional resistance generated in a sliding por tion by providing a slight gap in the sliding portion between a cylinder portion and a free piston and using an oil film generated in this gap as a sealing and a lubricating oil film. CONSTITUTION:A surge absorbing device 30 has a cylindrical container type housing 32 having a main pipe line portion 31 which forms a part of high- pressure oil passage 25, a free piston 33, and a spring 34, etc. A slight gap 46 in a degree of forming an oil film is provided between the outer peripheral face of a piston main portion 42 and the inner peripheral face of a cylinder portion 36, and part of high-pressure working fluid flowing in the main pipe line portion 31 can be moved into the housing 32 through the gap 46.