Hydraulic vibration isolation device

Abstract

A hydraulic vibration isolator with sub-orifices having each rubber valve is provided, such that is aimed at ensuring a sufficient orifice length for a main orifice (). An intermediate cylinder () disposed between an inner and an outer cylinders () is comprised of fitting peripheral walls () at both ends and joining walls () between them; a first and a second liquid chambers () are delimited by a vibration-isolating base body () interconnecting the joining walls and the inner cylinder; the fitting peripheral walls and the inner cylinder are interconnected by end walls () of rubber-like elastomer, and orifice-forming parts () are provided on the outer surface sides of the joining walls. At the orifice-forming parts, a channel () having a first rubber valve () forming a first sub-orifice (), a channel () having a second rubber valve () forming a second sub-orifice (), and fitting recessed portions () are provided. In the first and second liquid chambers, main orifice-forming members () having respective channels () on their outer peripheral surfaces are disposed, and fitting protrusions () on both ends thereof are fitted in the fitting recessed portions, whereby the main orifice through which both liquid chambers communicate is formed.