Hydraulic exhaust pipe hanger mount

Abstract

A hydraulic mount assembly includes a pair of mounting members and a first resilient body member and a second resilient body member connected thereto, each body member preferably being substantially bell shaped and forming a cavity. The two body members are connected with the cavities facing each other and separated by an orifice plate to form a closed chamber. A decoupler is mounted in the plate to provide the desired damping action. The body members are preferably molded of elastomeric material, such as rubber, with the first wall portion of the first body exhibiting relatively high stiffness, a second wall portion exhibiting relatively low stiffness and the second body including a third wall portion exhibiting relatively intermediate stiffness. Preferably, the ratio of the three stiffness ratings is 2:0.25:1. In operation, under dynamic loading, the stiff portion of the first body does not allow any dimension change in the longitudinal direction. Consequently, the relatively less stiff second body is caused to stretch or bulge under tensile or compressive loading, respectively. As this occurs, the volume of the second cavity is decreased or increased accordingly causing the appropriate exchange of fluid between the cavities through the orifice. The second portion of the first body accomodates this exchange by flexing inwardly or bulging outwardly depending on the decrease or increase of hydraulic fluid in that cavity.