tailieunhanh - vanced Vehicle Technology P2

This configuration enables the rubber to be loaded in both shear and compression with the majority of engine rotational flexibility being carried out in shear. Vertical deflection due to body pitch when accelerating or braking is absorbed mostly in compression. Vertical elastic stiffness may be increased without greatly effecting engine roll flexibility by having metal spacer interleafs bonded into the rubber. Double inclined wedge with longitudinal control mounting (Fig. (d)) Where heavy vertical loads and large rotational reactions are to be absorbed, double inclined wedge mounts positioned 22. | Fig. contd designed to be used with convergent V formation engine suspension system where the blocks are inclined on either side of the engine. This configuration enables the rubber to be loaded in both shear and compression with the majority of engine rotational flexibility being carried out in shear. Vertical deflection due to body pitch when accelerating or braking is absorbed mostly in compression. Vertical elastic stiffness may be increased without greatly effecting engine roll flexibility by having metal spacer interleafs bonded into the rubber. Double inclined wedge with longitudinal control mounting Fig. d Where heavy vertical loads and large rotational reactions are to be absorbed double inclined wedge mounts positioned on either side of the power unit s bell housing at principal axis level may be used. Longitudinal movement is restricted by the double V formed between the inner and two outer members seen in a plan view. This V and wedge configuration provides a combined shear and compressive strain to the rubber when there is a relative fore and aft movement between the engine and chassis in addition to that created by the vertical loading of the mount. This mounting s major application is for the rear mountings forming part of a four point suspension for heavy diesel engines. Metaxentric bush mounting Fig. e When the bush is in the unloaded state the steel inner sleeve is eccentric relative to the outer one so that 22 there is more rubber on one side of it than on the other. Precompression is applied to the rubber expanding the inner sleeve. The bush is set so that the greatest thickness of rubber is in compression in the laden condition. A slot is incorporated in the rubber on either side where the rubber is at its minimum in such a position as to avoid stressing any part of it in tension. When installed its stiffness in the fore and aft direction is greater than in the vertical direction the ratio being about 1. This type of bush .