Liquid filled bushing assembly

Patent metadata

Field	Value
Publication number	US-11441635-B2
Application number	US-202016790258-A
Country	US
Kind code	B2
Filing date	Feb 13, 2020
Priority date	Feb 15, 2019
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

A liquid filled bushing assembly includes an inner tubular member (11), an outer tubular member (12) disposed in a coaxial relation to the inner tubular member, and an elastic member (13) interposed between the inner tubular member and the outer tubular member, wherein not only the stiffness of the liquid filled bushing assembly in the lateral directions can be freely selected but also the stiffness of the liquid filled bushing assembly in the rotational direction and/or the axial direction can be freely selected.

First claim

The invention claimed is:

1. A liquid filled bushing assembly, comprising:
an inner tubular member having a central axial line;
an outer tubular member surrounding the inner tubular member in a coaxial relationship with an annular space defined therebetween; and
a tubular elastic member interposed and connected between the inner tubular member and the outer tubular member and defining a first to a fourth liquid chamber arranged in a circumferential direction at a regular interval in that order,
the tubular elastic member defining a first communication passage communicating the first liquid chamber with the third liquid chamber, a second communication passage communicating the second liquid chamber with the fourth liquid chamber, a third communication passage communicating the first liquid chamber with the second liquid chamber, and a fourth communication passage communicating the third liquid chamber with the fourth liquid chamber;
wherein the first liquid chamber, the second liquid chamber, the third liquid chamber, the fourth liquid chamber, the first communication passage, the second communication passage, the third communication passage, and the fourth communication passage are filled with viscous fluid,
wherein the liquid chambers are configured such that cubic capacities of the first and second liquid chambers change in a mutually complementary manner, and cubic capacities of the third and fourth liquid chambers change in a mutually complementary manner when the inner tubular member is moved relative to the outer tubular member along the central axial line,
the cubic capacities of the first and second liquid chambers change in a mutually complementary manner, and the cubic capacities of the third and fourth liquid chambers change in a mutually complementary manner when the inner tubular member is rotated relative to the outer tubular member around the central axial line,
the cubic capacities of the first and third liquid chambers change in a mutually complementary manner when the inner tubular member is moved relative to the outer tubular member in a first direction along which the first and third liquid chambers are arranged, and
the cubic capacities of the second and fourth liquid chambers change in a mutually complementary manner when the inner tubular member is moved relative to the outer tubular member in a second direction along which the second and fourth liquid chambers are arranged,
wherein the outer tubular member includes a coil disposed in a coaxial relationship to the inner tubular member, and a yoke having an axial gap located inside the coil, and the viscous fluid consists of a magnetic fluid having a viscosity that increases when subjected to a magnetic field, at least one of the communication passages extending through the axial gap,
wherein the coil includes a first coil, a second coil and a third coil that are arranged along the central axial line in a mutually spaced apart relationship, and the yoke defines first to third axial gaps serving as magnetic gaps corresponding to the first to third coils, respectively,
wherein the first communication passage passes through the first axial gap, the second communication passage passes through the second axial gap, and the third communication passage passes through the third axial gap,
wherein magnetic circuits formed by the first coil, the second coil, and the third coil, respectively, produce corresponding magnetic fields,
wherein the magnetic circuit corresponding to the first coil performs a function of concentrating the magnetic field generated by the first coil in the first axial gap so that the magnetic field corresponding to the first coil is applied to a first circumferential passage which passes through the first axial gap and that a stiffness of the liquid filled bushing assembly in the first direction is increased when the magnetic field is applied to the first circumferential passage,
wherein the magnetic circuit corresponding to the second coil performs a function of concentrating the magnetic field generated by the second coil in the second axial gap so that the magnetic field corresponding to the second coil is applied to a second circumferential passage which passes through the second axial gap and that a stiffness of the liquid filled bushing assembly in the second direction is increased, and
wherein the magnetic circuit corresponding to the third coil performs a function of concentrating the magnetic field generated by the third coil in the third axial gap so that the magnetic field corresponding to the third coil is applied to a third circumferential passage which passes through the third axial gap and that a stiffness in a vertical direction and a stiffness in a rotational direction of the liquid filled bushing assembly are increased.

2. The liquid filled bushing assembly according to claim 1 , wherein the tubular elastic member is provided with a first to a fourth radial wall extending in a radial direction with respect to the central axial line and arranged around the central axial line in that order, four first end wall parts attached to corresponding first axial ends of the radial walls, and four second end wall parts attached to corresponding second axial ends of the radial walls in such a manner that the first to fourth liquid chambers are defined by the first to fourth radial walls, the four first end wall parts and the four second end wall parts.

3. The liquid filled bushing assembly according to claim 2 , wherein a high bending stiffness portion having a relatively high bending stiffness is provided in radially inner parts of the first end wall part defining a first axial end of the first liquid chamber and the second end wall part defining a second axial end of the second liquid chamber, and another high bending stiffness portion having a relatively high bending stiffness is provided in radially outer parts of the second end wall part defining a second axial end of the first liquid chamber and the first end wall part defining a first axial end of the second liquid chamber.

4. The liquid filled bushing assembly according to claim 3 , wherein the high bending stiffness portions include a reinforcing plate provided in each of the corresponding end wall parts.

5. The liquid filled bushing assembly according to claim 2 , wherein a high bending stiffness portion having a relatively high bending stiffness is provided in radially inner parts of the first radial wall and the third radial wall, and another high bending stiffness portion having a relatively high bending stiffness is provided in radially outer parts of the second radial wall and the fourth radial wall.

6. The liquid filled bushing assembly according to claim 5 , wherein the high bending stiffness portions include a reinforcing plate provided in each of the corresponding radial walls.

7. The liquid filled bushing assembly according to claim 1 , wherein the outer tubular member further includes a passage forming member made of material having a low magnetic permeability and enclosing the axial gap from a radially inner side thereof so as to define the at least one of the communication passages extending through the axial gap in cooperation with the coil and the yoke.

Assignees

• Honda Motor Co Ltd

Inventors

• Ito Yuho
• Inoue Toshio

Classifications

• F16F13/1463

  characterised by features of passages between working chambers · CPC title

• F16F2222/06

  Magnetic or electromagnetic · CPC title

• F16F13/305 Primary

  magnetorheological · CPC title

• F16F2228/066

  Variable stiffness · CPC title

• F16F2224/045

  magnetorheological · CPC title