Vibration isolating bushing with embedded speed/position sensor

• US 20060220330A1
• Filed: 11/07/2005
• Published: 10/05/2006
• Est. Priority Date: 03/31/2005
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Urquidi, Carlos A., Rodriguez, Hector H.
• Granted Patent: US 7,360,756 B2
• Time in Patent Office: Days
• US Class Current: 280/5.516
• CPC Class Codes: B60G 17/01933 Velocity, e.g. relative velocity-displacement sensors
• CPC Class Codes: B60G 2200/142 with a single lateral arm, e.g. MacPherson type
• CPC Class Codes: B60G 2204/11 Mounting of sensors thereon
• CPC Class Codes: B60G 2204/116 Sensors coupled to the suspension arm
• CPC Class Codes: B60G 2204/143 on the vehicle body or chassis
• CPC Class Codes: B60G 2204/41 Elastic mounts, e.g. bushings
• CPC Class Codes: B60G 2204/41042 by using internal cam surfaces
• CPC Class Codes: B60G 2400/05162 the element being a suspension arm
• CPC Class Codes: B60G 2400/052 Angular rate
• CPC Class Codes: B60G 2400/202 Piston speed; Relative velocity between vehicle body and wheel
• CPC Class Codes: B60G 2400/252 vertical
• CPC Class Codes: B60G 2401/172 Hall effect
• CPC Class Codes: B60G 7/02 Attaching arms to sprung part of vehicle B60G7/006 takes precedence
• CPC Class Codes: F16F 1/38 with a sleeve of elastic material between a rigid outer sleeve and a rigid inner sleeve or pin , i.e. bushing-type hydraulically-damped bushes F16F13/14; suppression of vibrations in rotating systems by making use of elastomeric spring members between rotating elements, driveline torque being transmitted therebetween F16F15/126, by making use of a dynamic damping mass attached to a rotating element by means of elastomeric springs F16F15/14; pivots per se F16C11/00; elastic or yielding bearings or bearing supports F16C27/00; parts of sliding-contact bearings, e.g. bushes F16C33/04
• CPC Class Codes: F16F 2230/08 Sensor arrangement

Abstract

A bushing assembly adapted for application in vehicle suspension systems includes an embedded position sensor and an embedded speed sensor.

Claims

1. A bushing assembly comprising:

an outer member;

an inner member arranged substantially concentrically with the outer member;

an elastomeric member disposed between and interconnecting the inner and outer members; and

a speed sensor at least partially embedded within the elastomeric member and operative to produce an output signal indicative of the relative speed between the inner and outer members.

2. The assembly of claim 1, wherein the output signal from the speed sensor represents a relative speed between the members without having to differentiate the signal with respect to time.

3. The assembly of claim 2, wherein one of the members is established by a stator assembly and the other of the members is established by a rotor assembly.

4. The assembly of claim 3, wherein the stator assembly includes at least first and second opposed radially tapered stator poles and the rotor assembly includes at least first and second radially inwardly extending tapered rotor poles.

5. The assembly of claim 1, further comprising:

a magnet borne by at least one of the first member or the second member;

a galvanomagnetic sensing element borne by at least one of the first member or the second member;

wherein

an air gap is established between the members which varies dimensionally as a function of the relative angular position of the members.

6. The assembly of claim 1, wherein the speed sensor is contactless.

7. The assembly of claim 3, wherein the stator assembly is on the first member and the first member is an inner member, the rotor being on the second member the second member surrounding the first member.

18. The assembly of claim 1, wherein the speed sensor is at least one coil.

8. A speed sensing system, comprising:

at least one bushing assembly including a moving part, a non-moving part, and at least one elastomeric material therebetween, at least one sensor being disposed at least partially in the elastomeric material and generating a signal representing at least one parameter selected from the group including;

relative position between the parts, and relative speed between the parts; and

means receiving the signal for outputting a speed signal representing relative speed between the parts.

9. The system of claim 8, wherein the sensor is a position sensor and the means for outputting includes an electronic circuit differentiating the signal with respect to time to generate the speed signal.

10. The system of claim 8, wherein the sensor is a speed sensor and the means for outputting does not include an electronic circuit differentiating the signal with respect to time.

11. The system of claim 8, wherein the moving part is a rotor and the non-moving part is a stator surrounded by the rotor.

12. The system of claim 11, wherein the bushing assembly is engaged with a lower control arm of a vehicle suspension, and the speed signal is used by a control system to establish a stiffness of at least one shock absorber in the vehicle.

19. The system of claim 10, wherein the speed sensor is at least one coil.

13. A bushing assembly for a vehicle, comprising:

a stator engageable with a first part of a vehicle;

a rotor engageable with a second part of the vehicle;

a resilient material disposed between the stator and rotor; and

at least one speed sensor engaged with the rotor or the stator for outputting a signal that is directly proportional to the relative speed between the parts without having to differentiate the signal with respect to time.

14. The assembly of claim 13, wherein the speed sensor is at least one coil wound around a portion of the stator.

15. The assembly of claim 14, comprising a magnet on the stator.

16. The assembly of claim 15, wherein the stator defines at least one stator pole face and the rotor defines at least one rotor pole face, the pole faces being configured to establish an output of the coil sensor that varies substantially linearly with the relative speed between the rotor and stator.

17. The assembly of claim 16, further comprising a position sensor on the rotor or the stator.

20. The assembly of claim 13, wherein the bushing assembly is engaged with a lower control arm of a vehicle suspension, and the signal is used by a control system to establish a stiffness of at least one shock absorber in the vehicle.