Patent ID: 7967282

Claim:
A vibration isolator, comprising: a shaft having a first end and a second end, the shaft including a radial plate extending radially outwardly from the shaft and disposed between the first end and the second end; a first bushing mounted to the shaft at an axial position between the radial plate and the second end of the shaft, the first bushing having a first end and a second end, the second end of the first bushing including a flange extending radially outwardly therefrom; a second bushing disposed on the shaft and positioned between the radial plate and the first bushing, the second bushing having a first end, a second end, and an opening extending between the first end and the second end, the first end of the second bushing spaced apart from the second end of the first bushing to form a first axial gap, the second end including a flange extending radially outwardly therefrom and positioned adjacent to the radial plate forming an axial clearance therewith, and the opening having a diameter that is greater than a diameter of the shaft such that a radial gap is formed between the second bushing and the shaft; a first outer annular member disposed concentric to the first bushing and having an attachment face; a second outer annular member disposed concentric to the second bushing and having an attachment face that is spaced apart from the attachment face of the second outer annular member to form a second axial gap; a first elastomeric member disposed concentric to the shaft between the first outer annular member and the first bushing, the first elastomeric member having a first end and a second end, the first end of the first elastomeric member abutting the flange of the first bushing; a second elastomeric member disposed concentric to the shaft between the second outer annular member and the second bushing, the second elastomeric member having a first end and a second end, the first end of the second elastomeric member abutting the flange of the second bushing; and a shim disposed between the second end of the first bushing and the second end of the second bushing and between the attachment face of the first outer annular member and the attachment face of the second outer annular member, the shim having a portion having a first thickness and a portion having a second thickness, the first thickness being substantially equal to an axial length of the first axial gap, and the second thickness being substantially equal to an axial length of the second axial gap. wherein the first elastomeric member is adapted to provide a first stiffness for damping a first vibration, and the second elastomeric member is adapted to provide a second stiffness for damping a second vibration, the second stiffness being greater than the first stiffness.