Vibration damping bushing and manufacturing method of vibration damping bushing

Patent metadata

Field	Value
Publication number	US-9752637-B2
Application number	US-201514712356-A
Country	US
Kind code	B2
Filing date	May 14, 2015
Priority date	Jun 27, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A manufacturing method of a vibration damping bushing wherein an outer cylindrical member arranged on an outer peripheral side of an inner axial member is provided with on its both axial sides a pair of first inclined cylindrical parts each having a diameter gradually reduced toward an axial outside and a pair of second inclined cylindrical parts each extending further toward the axial outside from an axial end of the corresponding first inclined cylindrical part with an inclination angle smaller than that of the first inclined cylindrical part. The outer cylindrical member is arranged on the outer peripheral side of the inner axial member to be connected thereto by a main rubber elastic body. Axial ends of the main rubber elastic body are deformed by increasing the inclination angle of the second inclined cylindrical parts of the outer cylindrical member through a drawing operation.

First claim

What is claimed is:

1. A manufacturing method of a vibration damping bushing wherein an outer cylindrical member is arranged on an outer peripheral side of an inner axial member, and the inner axial member and the outer cylindrical member are connected in a radial direction by a main rubber elastic body, the method comprising:
providing the outer cylindrical member on its both axial sides with a pair of first inclined cylindrical parts each having a diameter gradually reduced toward an axial outside and a pair of second inclined cylindrical parts each extending further toward the axial outside from an axial end of the corresponding first inclined cylindrical part with an inclination angle smaller than that of the first inclined cylindrical part;
arranging the outer cylindrical member on the outer peripheral side of the inner axial member and connecting the outer cylindrical member and the inner axial member via the main rubber elastic body; and then
deforming axial ends of the main rubber elastic body by deforming the second inclined cylindrical parts of the outer cylindrical member through a drawing operation so that a difference between the inclination angles of the first inclined cylindrical parts and the second inclined cylindrical parts made smaller,
wherein the drawing operation includes increasing the inclination angle of the second inclined cylindrical parts while maintaining the inclination angle of the first inclined cylindrical parts.

2. The manufacturing method of the vibration damping bushing according to claim 1 , wherein the drawing operation includes setting the inclination angle of the second inclined cylindrical parts after the drawing operation at not more than that of the first inclined cylindrical parts after the drawing operation.

3. The manufacturing method of the vibration damping bushing according to claim 1 , wherein lightening holes are provided so as to open onto both axial end faces of the main rubber elastic body, and an axial bottom face of each lightening hole is located on an inner peripheral side of the corresponding first inclined cylindrical part before the drawing operation of the outer cylindrical member.

4. The manufacturing method of the vibration damping bushing according to claim 1 , wherein lightening holes are provided so as to open onto both axial end faces of the main rubber elastic body, and an axial bottom face of each lightening hole is located on an inner peripheral side of the corresponding second inclined cylindrical part by means of compressive deformation exerted on the main rubber elastic body in an axis-perpendicular direction through the drawing operation to cause swelling deformation to both axial sides thereof.

5. The manufacturing method of the vibration damping bushing according to claim 1 , wherein pre-compression is applied to the main rubber elastic body through a drawing operation of an axial center portion and the first inclined cylindrical parts of the outer cylindrical member to reduce their diameters as well.

6. The manufacturing method of the vibration damping bushing according to claim 1 , wherein during arranging the outer cylindrical member on the outer peripheral side of the inner axial member and connecting the outer cylindrical member and the inner axial member via the main rubber elastic body, no undercut in an axial direction is set at each axial end of the main rubber elastic body against an axial opening of the outer cylindrical member, while by increasing the inclination angle of each second inclined cylindrical part through the drawing operation thereafter, an undercut in the axial direction is set at the axial end of the main rubber elastic body against the axial opening of the outer cylindrical member on an inner peripheral side of the outer cylindrical member.

7. The manufacturing method of the vibration damping bushing according to claim 1 , wherein a protrusion is provided to an outer peripheral face of the inner axial member at a location separated peripherally inward from an axial middle portion of the outer cylindrical member, and an inner peripheral face of an axial middle portion of the main rubber elastic body is fixed to the protrusion.

8. The manufacturing method of the vibration damping bushing according to claim 1 , wherein a recess is provided to an outer peripheral face of the inner axial member at a location separated peripherally inward from a distal end of each second inclined cylindrical part so that the second cylindrical part and the recess are arranged at positions corresponding to each other in the axial direction, and an inner peripheral face of each axial end of the main rubber elastic body is fixed to the recess.

9. The manufacturing method of the vibration damping bushing according to claim 1 , wherein the inner axial member, the outer cylindrical member, and the main rubber elastic body are formed in rotational symmetry about a central axis.

10. The manufacturing method of the vibration damping bushing according to claim 4 , wherein before the drawing operation against the second inclined cylindrical parts, the axial bottom face of the each lightening hole is positioned on an inner peripheral side of the first inclined cylindrical part, and after the drawing operation against the second inclined cylindrical parts, the axial bottom face of the each lightening hole is moved to a position on the inner peripheral side of the corresponding second inclined cylindrical part.

Assignees

• Sumitomo Riko Co Ltd

Inventors

• Kuki Norimasa
• Kume Takashi

Classifications

• F16F2226/04

  Assembly or fixing methods; methods to form or fashion parts · CPC title

• F16F1/3842 Primary

  Method of assembly, production or treatment; Mounting thereof (supports for pipes, cables or protective tubing F16L3/00) · CPC title

• F16F1/393

  with spherical or conical sleeves · CPC title