Patent ID: 6250616
Filing Date: 2001-06-26
Classification: F16F

Abstract:
A fluid-filled vibration damping device for connecting two members to each other in a vibration damping fashion, comprising:a first mounting member which is adapted to be attached to one of the two members;a second mounting member which is adapted to be attached to the other of the two members;an elastic rubber body which elastically connects the first and second mounting members to each other and which provides a portion of a fluid-chamber wall defining a fluid chamber filled with a non-compressible fluid; anda working member which is supported by the first mounting member such that the working member extends, in the fluid chamber, in a first direction substantially perpendicular to a second direction in which a main vibrational load is applied to the fluid-filled vibration damping device, and thereby divides the fluid chamber into two divided chambers which are located, in the second direction, on opposite sides of the working member, respectively, and which are communicated with each other via a fluid-flow restricting passage defined by at least the working member,at least one of a length of the fluid-flow restricting passage in the second direction and a width of the restricting passage in the first direction changing in a circumferential direction of the working member,the restricting passage consisting of (a) a pair of first fluid-flow portions which are opposed to each other in the first direction, each of the two first fluid-flow portions extending over an angle of from 30 degrees to 80 degrees in the circumferential direction of the working member, and having a first ratio, A.sub.s /L.sub.s, of a cross-section area, A.sub.s, thereof to the length, L.sub.s, thereof; and (b) a pair of second fluid-flow portions which are opposed to each other in a direction perpendicular to each of the first and second directions, each of the two second fluid-flow portions extending over an angle of from 150 degrees to 100 degrees in the circumferential direction of the working member, and having a second ratio, A.sub.w /L.sub.w, of a cross-section area, A.sub.w, thereof to the length, L.sub.w, thereof, the second ratio A.sub.w /L.sub.w being greater than the first ratio A.sub.s /L.sub.s, anda ratio, (A.sub.s /L.sub.s)/(A.sub.w /L.sub.w), of the first ratio A.sub.s /L.sub.s to the second ratio A.sub.w /L.sub.w being not smaller than 1/10 and being not greater than 1/2.