Patent ID: 7293634
Filing Date: 2007-11-13
Classification: F16F

Abstract:
1. A hydraulic shock absorber comprising a cylindrical chamber ( 3 ), which is closed at one end and in which is axially slidably guided a piston member ( 5 ), supported by a piston rod ( 8 ) and at a peripheral surface of the piston member ( 5 ) carrying a surrounding non-slotted elastic ring element ( 6 ), the peripheral surface of the piston member ( 5 ) being conically converging in a direction away from the closed chamber end and the inner surface of the ring element also conically converging in the same direction, the ring element ( 6 ) furthermore being axially reciprocably mounted on the piston member ( 5 ) between a first rigid abutment ( 4 ) at the end of said member ( 5 ) closest to the closed end ( 10 ) of the chamber ( 3 ), and a second rigid abutment ( 7 ) on the piston member ( 5 ) at a spacing from the first abutment ( 4 ) exceeding the axial length of the ring element ( 6 ), characterized in that the two conical surfaces have mutually different conicity with core angles and diameters such selected that in an outward return movement of the piston member ( 5 ), the piston member ( 5 ) and the steeper conical peripheral surface of the piston member ( 5 ) are urged against the less conical inner surface of the surrounding ring element ( 6 ) and bring the first abutment ( 4 ) into engagement with the yieldable ring element ( 6 ) while, at the same time, radially expanding the ring element ( 6 ) so as to leave only a small intentional clearance for letting through hydraulic fluid between the outer surface of the ring element ( 6 ) and the inner surface of the cylindrical chamber.