초록 ▼

A hydraulic vibration damper featuring reduced noise characteristics wherein a first and a second damping valve system operate in response to fluid pressure to control flow of damping fluid in each direction of movement, respectively, of a piston of the damper. The first and second damping valve sys

A hydraulic vibration damper featuring reduced noise characteristics wherein a first and a second damping valve system operate in response to fluid pressure to control flow of damping fluid in each direction of movement, respectively, of a piston of the damper. The first and second damping valve systems include a preliminary throttling aperture, an aperture disc defining a preliminary aperture located downstream relative to the direction of fluid flow through the respective damping valve systems, and a noise reduction mechanism for producing a post-throttling effect downstream of the preliminary aperture, the noise reduction mechanism being formed by a baffle plate located to be impinged by fluid flowing through the preliminary aperture, the baffle plate being arranged to define a quieting duct immediately adjacent the baffle plate upstream thereof.

대표청구항 ▼

A hydraulic vibration damper unit comprising (A) a cylinder member (1) having an axis and two ends defining a cavity (8, 9) therein; said cavity containing a fluid; (B) a piston rod member (2) passing through one of said ends along said axis and being movable in an inward and an outward direction al

A hydraulic vibration damper unit comprising (A) a cylinder member (1) having an axis and two ends defining a cavity (8, 9) therein; said cavity containing a fluid; (B) a piston rod member (2) passing through one of said ends along said axis and being movable in an inward and an outward direction along said axis; (C) a piston unit fixed to said piston rod member (2) within said cavity (8, 9) and dividing said cavity (8, 9) into two working chambers (8, 9) consisting of a first working chamber (8) adjacent one of said ends of said cylinder member (1) and a second working chamber (9) adjacent the other of said ends of said cylinder member (1), said piston unit comprising (a) a piston member (3); (b) first passage means between said working chambers (8, 9); (c) second passage means (22, 15, 17, 18) between said working chambers (8, 9), said second passage means (22, 15, 17, 18) including at least one substantially axially directed bore (22) through said piston member (3), said bore (22) having a first end adjacent said one end of said cylinder member (1) and a second end remote from said one end of said cylinder member (1); (d) check valve means operatively associated with said second passage means (22, 15, 17, 18) and increasingly opening said second passage means in response to outward movement of said piston unit, said check valve means comprising (d1) an annular valve seat (16) on said piston member (3) radially outwardly of said second end of said bore (22); (d2) an annular disc member (14) substantially perpendicular to said axis substantially covering said second end of said bore (22), said annular disc member (14) being axially fixed with respect to said piston member (3) radially inwardly of said second end of said bore (22) and being yieldingly biased into contact with said annular valve seat (16), said annular disc member (14) being provided with at least one opening (15); (d3) an annular plate member (11) substantially perpendicular to said axis adjacent said annular disc member (14) on the side thereof remote from said annular valve seat (16), said annular plate member (11) being provided with an axial projection (13) engaging said annular disc member (14) along a circle substantially following said annular valve seat (16) and with an annular recess (17) radially inward of said annular projection (13), said annular recess (17) having a bottom face (12) spaced from said annular disc member (14) and being opposed to said opening (15), at least one substantially axially directed channel (18) being provided between said annular recess (17) and said second working chamber (9) at a location radially inward of said opening (15), said annular plate member (11) being axially movable and urged into a closing position by spring means (25) urging said projection (13) into contact with said annular disc member (14), said annular disc member (14) and said annular plate member (11) being movable away from said annular valve seat (16) by deflection of said annular disc member (14) and axial movement of said annular plate member (11) in response to increase of fluid pressure in said first working chamber (8) above the level of fluid pressure in said second working chamber (9) by a predetermined amount.