Tank rubber cushion
A tank rubber cushion for providing a vibration-damping support of a fuel tank against a vehicle body, including two divided rubber cylinders inserted onto an inner axial member having flanges at both axial ends and to be inserted through a mounting hole formed in a support portion of the fuel tank. Each of the divided rubber cylinders is provided with an axial vibration-damping rubber portion arranged between opposing surfaces of the flange of the inner axial member and the support portion in an axial direction, and a transaxial vibration-damping rubber portion arranged between opposing surfaces of the inner axial member and the support portion in a transaxial direction. The transaxial vibration-damping rubber portion includes a concave/convex portion wherein a diameter varies in a circumferential direction so that an assembly can be made with a gap between the inner axial member and the support portion.
1. A tank rubber cushion for providing a vibration-damping support of a fuel tank at multiple locations against a vehicle body, comprising:
an inner axial member adapted to be fixed to one of the fuel tank and the vehicle body, the inner axial member having flanges at both ends in an axial direction, respectively, and the inner axial member being adapted to be inserted through a mounting hole formed in a support portion provided to another of the fuel tank and the vehicle body, with the flanges of the inner axial member being placed at and facing to both sides of the support portion in the axial direction;
two divided rubber cylinders inserted onto an outer peripheral face of the inner axial member while facing each other in the axial direction;
an axial vibration-damping rubber portion in an annular form being provided on an axially outside portion of each of the divided rubber cylinders, and being arranged between opposing surfaces of the flange of the inner axial member and the support portion in the axial direction;
a transaxial vibration-damping rubber portion in a cylinder form being provided to an axially inside portion of each of the divided rubber cylinders, and being thrust into the mounting hole of the support portion from both sides in the axial direction so as to be arranged between opposing surfaces of the inner axial member and the support portion in a transaxial direction,
wherein the transaxial vibration-damping rubber portion of each divided rubber cylinder includes a concave/convex portion wherein a diameter varies in a circumferential direction so that an assembly is made with a gap between an outer periphery of the inner axial member and an inner periphery of the support portion along the concave/convex portion; and
an outer wall of the transaxial vibration-damping rubber portion of each divided rubber cylinder is defined by a first alternating concave/convex surface and an inner wall of the transaxial vibration-damping rubber portion of each divided rubber cylinder is defined by a second alternating concave/convex surface, and
a thickness between the first alternating concave/convex surface and the second alternating concave/convex surface, which thickness includes a thickness of the concave/convex portion in a diametrical direction, is constant in the circumferential direction.
2. The tank rubber cushion according to claim 1 , wherein the transaxial vibration-damping rubber portions of the two divided rubber cylinders are abutted against each other at respective end surfaces in the axial direction.
3. The tank rubber cushion according to claim 1 , wherein the transaxial vibration-damping rubber portions are made in a wavy form that consecutively changes the diameter in the circumferential direction.
4. The tank rubber cushion according to claim 3 , wherein the concave/convex portion of each of the transaxial vibration-damping rubber portions comprises a first wavy curved portion that is convex on an outside and a second wavy curved portion that is convex on an inside with continuously changing diameters in the circumferential direction, and
the concave/convex portion is adapted to allow an assembly where an apex of the first wavy curved portion abuts against the inner periphery of the support portion along an outer periphery thereof with the gap existing between an inner periphery thereof and the outer periphery of the inner axial member, while an apex of the second wavy curved portion abuts against the outer periphery of the inner axial member along an inner periphery thereof with the gap existing between an outer periphery thereof and the inner periphery of the support portion.
5. The tank rubber cushion according to claim 1 , wherein a concave groove is formed in the axial vibration-damping rubber portion opening toward an axially inside surface thereof while extending along a base of each of the transaxial vibration-damping rubber portions on an outer peripheral side thereof in the circumferential direction.
6. The tank rubber cushion according to claim 1 , wherein the two divided rubber cylinders are formed in a same shape as each other at least at each of the transaxial vibration-damping rubber portions.
7. The tank rubber cushion according to claim 1 , wherein the gap is provided between a concave surface of the second alternating concave/convex surface and the outer periphery of the inner axial member and between a concave surface of the first alternating concave/convex surface and the inner periphery of the support portion, and
abutting portions of a convex portion of the concave/convex portion that abuts the outer periphery of the inner axial member at the second alternating concave/convex surface are provided at different circumferential positions than the abutting portions of the convex portion of the concave/convex portion that abuts the inner periphery of the support portion at the first alternating concave/convex surface such that the concave/convex portion of each of the transaxial vibration-damping rubber portions undergo shear deformation upon input of a vibrational load in an axis-perpendicular direction.