| 摘要 |
PURPOSE: To enhance sealing lifetime by fixing an oil-impregnated metal disk to house lubricant on the top face of a piston head and pouring a part of the lubricating oil pressurized at the time of gas compression into a sealing groove between bore walls. CONSTITUTION: On a reciprocation of a piston head 32 within a cylinder 10 gas from a gas feeding container 80 is compressed by means of inlet/outlet 18, non-return check valves 84, 88 and directional selecting valve 90. Onto the top face 36 of the piston head 32, an oil-impregnated metal disk is fixed and a lubricant layer 70 is formed by feeding lubricant from a lubricant feeding hole 20. When gas is compressed, a part of the lubricant is poured into a sealing groove 42 by way of a plurality of ducts 38 between bore wall faces, fills the upper gaps of the first and second sealing members 50, 58 and gas-sealing is performed. In this way, constant feeding of lubricant into the sealing grooves is possible to enable sealing lifetime to extend over a long period of time. |
