| 摘要 |
PROBLEM TO BE SOLVED: To provide an air compressor which has a piston equipped with a lip ring, and has a piston structure capable of further improving the durability of the lip ring.SOLUTION: A compressor has a lip ring 7 for sealing a part between a piston portion 51 and a cylinder 31. A piston 5 of the compressor has: a foundation portion 54 which becomes a foundation of the lip ring attached to the piston portion; a curved portion 56 formed on the outside of the foundation portion and abutting on an R portion on a lip ring bottom surface side; and a generally plane surface 57 formed on the outside of the curved portion, and generally vertical to a piston axial direction. The curved portion is formed between the foundation portion and the generally plane surface, and the generally plane surface is formed on an outer edge portion of the piston portion. The width of the generally plane surface is preferably 1/2 or more of plate thickness dimensions of the lip ring. With this characteristics, the deformation of the lip ring R portion and the biting-in of the piston portion to the lip ring can be prevented, so that the durability of the lip ring is improved.SELECTED DRAWING: Figure 4 |
