FILTER-EMBEDDED HYDRAULIC PUMP AND MOTOR PISTON ASSEMBLY, CAPABLE OF PREVENTING THE SCRATCHES OF A STATIC PRESSURE BEARING DUE TO THE FOREIGN MATTER IN THE HIGH-PRESSURE OIL

摘要

PURPOSE: Filter-embedded hydraulic pump and motor piston assembly is provided to prevent the thickness change of the oil film and the ratio change of a static pressure bearing due to the scratches of the static pressure bearing.;CONSTITUTION: Filter-embedded hydraulic pump and motor piston assembly is composed of a piston(10), a shoe(30), a filter element(50), and a stopping ring(60). The high-pressure oil flows into the piston in a longitudinal direction. The piston is connected to one side of the shoe and a static pressure bearing(40) is formed on the other side. A part of the high-pressure oil of the piston flows into the static pressure bearing and works as lubricant. In order to prevent a scratch from becoming generated on the static pressure bearing by the foreign matter in the high-pressure oil and thus the thickness of an oil film to the swash plate making contact with the shoe from changing, the filter member is installed in the piston to filter the foreign matter. The stopping ring is installed on the inner circumferential surface of the piston, supports one end of the filter member and thus prevents the movement of the filter member due to the pressure of the high-pressure oil.;COPYRIGHT KIPO 2011