Active suspension system with electropermanent magnets

Patent metadata

Field	Value
Publication number	US-10759246-B1
Application number	US-201815907386-A
Country	US
Kind code	B1
Filing date	Feb 28, 2018
Priority date	Mar 8, 2017
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

A stability control system that detects a change in a vehicle operating characteristic and sends a stabilizing command to an actuator system based on identifying the change is described. The actuator system applies a first magnetic field having a predetermined strength to an electropermanent magnet for a predetermined duration based on receiving the stabilizing command. The first magnetic field transitions the electropermanent magnet from a first state to a second state. The electropermanent magnet generates a second magnetic field in the second state. The second magnetic field modifies at least one of a spring constant or a mechanical resistance of a suspension component within a suspension system of the vehicle, and the electropermanent magnet retains the second state after the predetermined duration in absence of the first magnetic field.

First claim

What is claimed is:

1. A method of stabilizing a vehicle, comprising:
identifying, by a control system, a change in a vehicle operating characteristic;
outputting, by the control system, a stabilizing command to an actuator system based on identifying the change in the vehicle operating characteristic; and
applying, by the actuator system, a first magnetic field having a predetermined strength to an electropermanent magnet for a predetermined duration based on receiving the stabilizing command, wherein:
the first magnetic field transitions the electropermanent magnet from a first state to a second state,
the electropermanent magnet does not generate a magnetic field in the first state,
the electropermanent magnet generates a second magnetic field in the second state,
the second magnetic field modifies at least one of a spring constant or a mechanical resistance of a suspension component within a suspension system of the vehicle, and
the electropermanent magnet retains the second state after the predetermined duration in absence of the first magnetic field.

2. The method of claim 1 , wherein the change in the vehicle operating characteristic is a reduction in wheel speeds to a level that indicates a lack of an external harmonic or oscillatory input to the vehicle.

3. The method of claim 2 , further comprising:
based on the second magnetic field modifying the spring constant to lock a position of a movable portion of the suspension component, changing, by the actuator system, a magnitude of a third magnetic field acting upon an electromagnet within the suspension component.

4. The method of claim 1 , wherein the change in the vehicle operating characteristic is an increase or a decrease in an external harmonic or oscillatory input to the vehicle consistent with a change in ride characteristics of the vehicle.

5. The method of claim 4 , wherein the predetermined strength of the first magnetic field is based on a magnitude of the change in the vehicle operating characteristic.

6. The method of claim 1 , wherein the predetermined duration of the first magnetic field is based on an amount of energy required to transition the electropermanent magnet from the first state to the second state.

7. The method of claim 1 , wherein a strength of the second magnetic field is based on the predetermined strength and the predetermined duration of the first magnetic field.

8. A suspension component for an active suspension system, comprising:
a first component that includes an electropermanent magnet, the electropermanent magnet having a first state and a second state;
a second component that includes a permanent magnet that magnetically interacts with the first component, wherein the magnetic interaction between the first component and the second component defines a damping characteristic that affects relative motion of the first component and the second component; and
a controller that is operable to supply a current pulse to the electropermanent magnet to switch an active state of the electropermanent magnet between the first state and the second state, wherein the electropermanent magnet retains the active state after cessation of the current pulse.

9. The suspension component of claim 8 , wherein the electropermanent magnet includes a first permanent magnet material, a second permanent magnet material that is different from the first permanent magnet material, and a coil.

10. The suspension component of claim 9 , wherein the first permanent magnet material has a larger magnetic coercivity than the second permanent magnet material.

11. The suspension component of claim 10 , wherein the current pulse changes a magnetic polarity of the second permanent magnet material to switch the active state of the electropermanent magnet between the first state and the second state.

12. The suspension component of claim 9 , wherein the current pulse from the controller is applied to the coil of the electropermanent magnet.

13. The suspension component of claim 12 , wherein application of the current pulse to the coil generates a magnetic field that causes the electropermanent magnet to switch the active state between the first state and the second state.

14. The suspension component of claim 8 , wherein the electropermanent magnet does not generate a magnetic field in the first state and the electropermanent magnet generates a magnetic field in the second state.

15. The suspension component of claim 8 , wherein the controller supplies the current pulse in response to detection of a change in a vehicle operating characteristic, and wherein the electropermanent magnet modifies at least one of a spring constant or a mechanical resistance of the suspension component in the active state.

16. A suspension component, comprising:
a first component that includes a first magnetic section that includes an electropermanent magnet and a second magnetic section that includes an electromagnet;
a second component that includes an alternating polarity permanent magnet having sections that alternate in polarity along an axial length of the second component, wherein magnetic interaction of the alternating polarity permanent magnet with the first magnetic section and the second magnetic section affects relative motion of the first component and the second component; and
a controller that is operable to supply a current pulse to the electropermanent magnet of the first magnetic section to switch an active state of the electropermanent magnet between a first state and a second state,
wherein the second component is locked relative to the first component when the active state of the electropermanent magnet is the first state,
wherein the controller supplies the current pulse in response to detection of a change in a vehicle operating characteristic, and
wherein the electropermanent magnet retains the active state after cessation of the current pulse.

17. The suspension component of claim 16 , wherein the second component is not locked relative to the first component when the active state of the electropermanent magnet is the second state.

18. The suspension component of claim 16 , wherein:
the electropermanent magnet includes a first permanent magnet material, a second permanent magnet material that is different from the first permanent magnet material, and a coil,
the first permanent magnet material has a larger magnetic coercivity than the second permanent magnet material, and
the current pulse is applied to the coil of the electropermanent magnet, and application of the current pulse to the coil generates a magnetic field that causes the electropermanent magnet to switch the active state between the first state and the second state by changing a magnetic polarity of the second permanent magnet material.

19. The suspension component of claim 15 , wherein the change in the vehicle operating characteristic is a reduction in wheel speeds to a level that indicates a lack of an external harmonic or oscillatory input to the vehicle.

20. The suspension component of claim 15 , wherein the change in the vehicle operating characteristic is an increase or a decrease in an external harmonic or oscillatory input to the vehicle consistent with a change in ride characteristics of the vehicle.

Assignees

• Erdozain Jr Jack
• Sewell Jeffrey A
• Wall Johnny L
• Szechy Colin
• Apple Inc

Inventors

• Erdozain Jr Jack
• Sewell Jeffrey A
• Wall Johnny L
• Szechy Colin

Classifications

• F16F2224/045

  magnetorheological · CPC title

• F16F2222/06

  Magnetic or electromagnetic · CPC title

• F16F15/03

  using {magnetic or} electromagnetic means (F16F9/53, {F16F15/005} take precedence) · CPC title

• F16F15/002

  characterised by the control method or circuitry (control of mechanical oscillations per se G05D19/00) · CPC title

• F16F6/00

  Magnetic springs {(magnetic spring arrangements for the suppression of vibration in systems F16F15/03)}; Fluid magnetic springs {, i.e. magnetic spring combined with a fluid} · CPC title