Patent ID: 8627758
Filing Date: 2014-01-14
Classification: F04B

Abstract:
1. An axial piston pump, comprising: a cylinder block having one or more cylinder bores; and one or more piston assemblies; wherein number of piston assemblies matches number of cylinder bores; wherein each of the piston assemblies having a piston being disposed reciprocating in each of the cylinder bores; wherein each piston being fitted with a metallic helical coiled sealing ring for reducing leakage and keeping concentric of the piston within its corresponding cylinder bore; wherein the metallic helical coiled sealing ring comprising partial rings having male and female dovetails on two ends of each partial ring; wherein the partial rings being progressively joined by the male and female dovetails to form a helical spring; and wherein the helical spring tube being further grinded on the inner diameter and outer diameter of the helical spring tube to make four different diameter circles, with two of the diameter circles on the inside and two of the diameter circles on the outside of the helical spring tube to form a seal assembly.