Abstract: A valve member formed of an elastomeric membrane for opening and closing a second orifice flow passage is mounted on a partition element such that the valve member is arranged orthogonal to the flow direction of the second orifice flow passage. A valve portion for closing openings of the second orifice flow passage due to flexural deformation of a flexible membrane portion caused by liquid flow in the second orifice flow passage is arranged on the flexible membrane, and communication holes for bring the second orifice flow passage into communication are formed in the flexible membrane portion. A cylindrical buffer portion projecting from the flexible membrane portion for surrounding the openings when the flexible membrane portion is deformed by flexure is provided to the valve portion, and a projection height of the cylindrical buffer portion is set larger than a wall thickness thereof.

Abstract: In a liquid-sealed type vibration isolator having a first orifice flow channel 56 and a second orifice flow channel 60, a valve member 66 formed of a rubber elastomeric membrane for opening and closing the second orifice flow channel 60 is provided on a partitioning member 40 so as to be orthogonal to the direction of flow in the second orifice flow channel. The valve member is held at the outer peripheral portion thereof by a wall surface of a valve housing chamber 68, and includes inside the outer peripheral portion thereof a membrane portion 66B which is subjected to the flexural deformation by the liquid flow in the second orifice flow channel to close openings 60C and 60D of the second orifice flow channel. Communicating holes 76 which bring the second orifice flow channel into communication are provided at positions not overlapped with the opening of the membrane portion 66B. Accordingly, the switching of characteristics is enabled with an inexpensive structure.

Abstract: In a liquid-sealed type vibration isolator having a first orifice flow channel 56 and a second orifice flow channel 60, a valve member 66 formed of a rubber elastomeric membrane for opening and closing the second orifice flow channel 60 is provided on a partitioning member 40 so as to be orthogonal to the direction of flow in the second orifice flow channel. The valve member is held at the outer peripheral portion thereof by a wall surface of a valve housing chamber 68, and includes inside the outer peripheral portion thereof a membrane portion 66B which is subjected to the flexural deformation by the liquid flow in the second orifice flow channel to close openings 60C and 60D of the second orifice flow channel. Communicating holes 76 which bring the second orifice flow channel into communication are provided at positions not overlapped with the opening of the membrane portion 66B. Accordingly, the switching of characteristics is enabled with an inexpensive structure.

Abstract: A valve member formed of an elastomeric membrane for opening and closing a second orifice flow passage is mounted on a partition element such that the valve member is arranged orthogonal to the flow direction of the second orifice flow passage. A valve portion for closing openings of the second orifice flow passage due to flexural deformation of a flexible membrane portion caused by liquid flow in the second orifice flow passage is arranged on the flexible membrane, and communication holes for bring the second orifice flow passage into communication are formed in the flexible membrane portion. A cylindrical buffer portion projecting from the flexible membrane portion for surrounding the openings when the flexible membrane portion is deformed by flexure is provided to the valve portion, and a projection height of the cylindrical buffer portion is set larger than a wall thickness thereof.

Abstract: In a liquid-sealed type vibration isolator having a first orifice flow channel 56 and a second orifice flow channel 60, a valve member 66 formed of a rubber elastomeric membrane for opening and closing the second orifice flow channel 60 is provided on a partitioning member 40 so as to be orthogonal to the direction of flow in the second orifice flow channel. The valve member is held at the outer peripheral portion thereof by a wall surface of a valve housing chamber 68, and includes inside the outer peripheral portion thereof a membrane portion 66B which is subjected to the flexural deformation by the liquid flow in the second orifice flow channel to close openings 60C and 60D of the second orifice flow channel. Communicating holes 76 which bring the second orifice flow channel into communication are provided at positions not overlapped with the opening of the membrane portion 66B. Accordingly, the switching of characteristics is enabled with an inexpensive structure.