Vibration-isolating mount device

摘要

A mounting member fixed to an engine and a mounting member fixed to a vehicle body are interconnected by a hollow elastomeric block which has a variable-volume primary fluid chamber defined therein. A subsidiary fluid chamber having a diaphragm on a portion of an outer wall thereof communicates with the primary fluid chamber through two fluid passages. A movable plate forming a portion of the outer wall of the primary fluid chamber is connected to a voice coil motor, and by one example, is driven at the same phase as a vibration applied from the engine. During a normal traveling, both the fluid chambers communicate with each other through the fluid passage having a smaller length. During idling or during a low speed traveling, a switch-over valve is operated to permit both the fluid chamber to be put into communication with each other through the fluid passage having a larger length. With the above construction, it is possible to stably exhibit the performance of the vibration-isolating mount device in a wide frequency region.