Hydraulic actuator with on-demand energy flow

• US 10,029,534 B2
• Filed: 03/14/2014
• Issued: 07/24/2018
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: ClearMotion, Inc.
• Original Assignee: ClearMotion, Inc.
• Inventors: Giovanardi, Marco, Tucker, Clive, Wendell, Ross J., Anderson, Zackary Martin, O'Shea, Colin Patrick, Gorelik, Vladimir, Sawyer, Tyson David, Leehey, Jonathan R., Schneider, Johannes, Driscoll, Robert, Neil, Patrick W., Avadhany, Shakeel
• Primary Examiner(s): Lopez, F. Daniel
• Assistant Examiner(s): Collins, Daniel
• Application Number:
  US14/212,443
• Publication Number:
  US 20140260233A1
• Time in Patent Office: 1,593 Days
• Field of Search: 60414
• CPC Class Codes: B60G 15/10 and mechanical damper or dynamic damper
• CPC Class Codes: B60G 17/016 characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input B60G17/017 takes precedence
• CPC Class Codes: B60G 2202/413 Hydraulic actuator
• CPC Class Codes: B60G 2204/11 Mounting of sensors thereon
• CPC Class Codes: B60G 2400/0511 Roll angle
• CPC Class Codes: B60G 2400/0521 Roll rate
• CPC Class Codes: B60G 2400/60 Load
• CPC Class Codes: B60G 2800/70 Estimating or calculating vehicle parameters or state variables
• CPC Class Codes: F04B 49/20 by changing the driving speed
• CPC Class Codes: F15B 13/0444 with rotary electric motor
• CPC Class Codes: F16K 11/065 with linearly sliding closure members
• CPC Class Codes: F16K 31/12 actuated by fluid fluid-actuated lift valves F16K1/126 ; fluid-actuated check valves F16K15/00; fluid-actuated safety valves F16K17/00

Abstract

Various embodiments related to hydraulic actuators and active suspension systems as well as their methods of use are described.

Claims

1. An actuation system comprising:

a hydraulic actuator including a first volume separated into an extension volume and a compression volume by a piston slidably received in the first volume;

a hydraulic motor-pump in fluid communication with the extension volume and the compression volume of the hydraulic actuator to control extension and compression of the hydraulic actuator, wherein upon operation of the hydraulic motor-pump in a first direction, fluid flows from the extension volume to the compression volume and upon operation of the hydraulic motor-pump in a second direction, fluid flows from the compression volume to the extension volume; and

an electric motor operatively coupled to the hydraulic motor-pump, wherein the actuation system has a reflected system inertia and a system compliance, wherein the system compliance is between 1/(7.9E+06) m/N and 1/(3.2E+03) m/N, and wherein a product of the system compliance times the reflected system inertia is less than or equal to 0.0063 s².

2. The actuation system of claim 1, wherein a product of the system compliance times the reflected system inertia is greater than or equal to 2.5×

10<sup>−

6</sup> s².

3. The actuation system of claim 1, wherein a response time of the actuation system is between 10 ms and 150 ms.

4. The actuation system of claim 1, wherein a natural frequency of the actuation system is between 2 Hz and 100 Hz.

5. The actuation system of claim 1, wherein at least one of the hydraulic motor-pump, and the electric motor are remotely located relative to the hydraulic actuator.

6. The actuation system of claim 1, wherein a pressure of the hydraulic actuator is substantially controlled by the hydraulic motor-pump operatively coupled to the electric motor.

7. The actuation system of claim 1, wherein the motor input is at least one of motor position, voltage, torque, impedance, frequency, and speed.

8. The actuation system of claim 1, further comprising a controller electrically coupled to the electric motor, wherein the controller applies a motor input to the electric motor to control the hydraulic actuator in at least three of four quadrants of a force velocity domain of the hydraulic actuator.

9. The actuation system of claim 8, wherein the hydraulic actuator is controlled to operate in all four quadrants of the force velocity domain of the hydraulic actuator.

10. The actuation system of claim 8, wherein the four quadrants of the force velocity domain include compression damping, extension damping, active extension, and active compression.

11. The actuation system of claim 1, wherein power is applied to and consumed by the electric motor only during active extension and/or active compression.

12. The actuation system of claim 1, wherein the hydraulic motor-pump operates in lockstep with the hydraulic actuator.

13. The actuation system of claim 1, wherein the electric motor is constructed and arranged to be operated as a generator.

14. The actuation system of claim 13, wherein the update frequency of the motor input is less than 1 kHz.

15. The actuation system of claim 14, wherein an update frequency of the motor input is greater than 0.5 Hz.

16. The actuation system of claim 1, wherein the hydraulic actuator, hydraulic motor-pump, and electric motor, are integrated with a single housing.

17. The actuation system of claim 1, where the hydraulic actuator is constructed and arranged to be coupled to at least one of an excavator arm, a control surface of an airplane, a fork lift, a lift boom, and an active suspension system.

18. The actuation system of claim 1, further comprising one or more valves located between the hydraulic actuator and the hydraulic motor-pump.

19. The actuation system of claim 1, wherein in at least one mode of operation the motor-pump is controlled to generate a pressure differential that acts on the piston to produce a force in a direction of motion of the piston.

20. The actuation system of claim 1, wherein upon operation of the hydraulic motor-pump in the first direction, fluid flows from the extension volume to the compression volume through the hydraulic motor-pump, and wherein upon operation of the hydraulic motor-pump in the second direction, fluid flows from the compression volume to the extension volume through the hydraulic motor-pump.

21. An actuation system comprising:

a hydraulic actuator including a first volume separated into an extension volume and a compression volume by a piston slidably received in the first volume;

a hydraulic motor-pump in fluid communication with the extension volume and the compression volume of the hydraulic actuator to control extension and compression of the hydraulic actuator, wherein upon operation of the hydraulic motor-pump in a first direction, fluid flows from the extension volume to the compression volume and upon operation of the hydraulic motor-pump in a second direction, fluid flows from the compression volume to the extension volume; and

an electric motor operatively coupled to the hydraulic motor-pump, wherein the actuation system has a reflected system inertia and a system compliance, wherein the reflected system inertia is between 1.26 kg and 3168 kg, and wherein a product of the system compliance times the reflected system inertia is less than or equal to 0.0063 s².