Liquid filled vibration isolation device

A vibration isolating device, comprising:

• a cylindrical body fitting having an upper portion defining an opening, and a lower portion;
• an attachment fitting;
• a vibration isolating substrate made of an elastomer;
• the lower portion of the cylindrical body fitting and the attachment fitting being coupled by the vibration isolating substrate;
• a diaphragm made of an elastic film bonded to the upper portion of the cylindrical body fitting to cover the opening at the upper portion;
• liquid contained in an inner chamber between the vibration isolating substrate and the diaphragm;
• a partition device partitioning the inner chamber into a main liquid chamber on a side of the attachment fitting and a first sub-liquid chamber on a side of the diaphragm by a partition portion;
• the partition device including a partition plate member with an elastic film as a center portion, and an orifice member contacting a circumferential portion of the elastic film of the partition plate member on the first sub-liquid chamber side to define a second sub-liquid chamber between the center portion of the partition plate member and a center plate portion of the orifice member;
• the partition device defining a first orifice formed between an outer circumferential portion of the orifice member and an outer circumferential portion of the partition plate member, the first orifice communicating the main liquid chamber with the first sub-liquid chamber;
• the center plate portion of the orifice member defining a second orifice communicating the first sub-liquid chamber to the second sub-liquid chamber;
• the center plate portion of the orifice member having a convex form with respect to the first sub-liquid chamber with a center apex portion faced toward the first sub-liquid chamber which is surrounded by a lower portion;
• and
• the second orifice being limited to the lower portion such that an entirety of the second orifice is below the center apex portion, and the second orifice being positioned on a side of the center apex portion opposite the first orifice.