Vibration damping apparatus

摘要

An engine mount for damping vibrations between a rigid armature (16) for connection to the engine of a motor vehicle and a rigid cover member (10) for connection to the body or chassis of the vehicle comprises a thick conically shaped rubber wall (18) integrally moulded with a thin flexible wall (26). The rubber is bonded to a rigid metal peripheral member (24) defining a channel (30,30A). A plate (32) fixed to the cover (10) closes off the hollow spaces under the walls (18,26) to define working and compensation chambers respectively which are connected by the channel (30,30A). The chambers and the communicating channel are filled with liquid. The peripheral member (24) defines a slot (40) having apertures connecting it respectively to the working and compensation chambers (36,38). A thin flexible rubber valve member (46) is located in the slot (40) with clearance. The valve member (46) oscillates in the slot in response to pressure fluctuations in the liquid in the working chamber (36) caused by low amplitude vibrations and transmits these fluctuations to the liquid in the compensation chamber. However, the valve member (40) is held stationary in response to larger amplitude vibrations and forces the oscillating liquid to flow through the communicating channel (30,30A). <IMAGE>