SYSTEM FOR RECOVERING ENERGY FROM A HYDRAULIC ACTUATOR

• US 20190203746A1
• Filed: 07/05/2017
• Published: 07/04/2019
• Est. Priority Date: 07/07/2016
• Status: Active Grant

• Current Assignee: Dana Italia S.R.L.
• Original Assignee: Dana Italia S.R.L.
• Inventors: BALBONI, LUCA, MOSER, DAVIDE, ZENDRI, FABRIZIO
• Granted Patent: US 10,844,885 B2
• Time in Patent Office: Days
• CPC Class Codes: B66C 23/54 with pneumatic or hydraulic motors, e.g. for actuating jib-cranes on tractors
• CPC Class Codes: E02F 9/2217 with energy recovery arrangements, e.g. using accumulators, flywheels
• CPC Class Codes: E02F 9/2225 using pressure-compensating valves
• CPC Class Codes: E02F 9/2267 Valves or distributors position of valves arrangements on upper-structures E02F9/0875
• CPC Class Codes: E02F 9/2271 Actuators and supports therefor and protection therefor
• CPC Class Codes: E02F 9/2282 Systems using center bypass type changeover valves
• CPC Class Codes: E02F 9/2285 Pilot-operated systems
• CPC Class Codes: E02F 9/2296 Systems with a variable displacement pump
• CPC Class Codes: F15B 1/027 having accumulator charging devices
• CPC Class Codes: F15B 11/10 in which the servomotor position is a function of the pressure also pressure regulators as operating means for such systems, the device itself may be a position indicating system
• CPC Class Codes: F15B 21/14 Energy-recuperation means
• CPC Class Codes: F15B 2211/205 Systems with pumps
• CPC Class Codes: F15B 2211/212 the pressure sources being accumulators
• CPC Class Codes: F15B 2211/30505 Non-return valves, i.e. check valves
• CPC Class Codes: F15B 2211/411 the positions being discrete
• CPC Class Codes: F15B 2211/428 actuated by fluid pressure
• CPC Class Codes: F15B 2211/50563 the pressure control means controlling a differential pressure
• CPC Class Codes: F15B 2211/50581 using counterbalance valves
• CPC Class Codes: F15B 2211/5756 for opening a valve
• CPC Class Codes: F15B 2211/7053 Double-acting output members
• CPC Class Codes: F15B 2211/7058 : Rotary output members
• CPC Class Codes: F15B 2211/7142 : the output members being arranged in multiple groups
• CPC Class Codes: F15B 2211/88 : Control measures for saving energy
• CPC Class Codes: F16H 61/4096 : with pressure accumulators
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles

Abstract

A system for recovering energy from a hydraulic actuator and to a method of operating the system are described. The system may have a hydraulic actuator and a source of hydraulic pressure, comprising a hydraulic pump, in fluid communication with the hydraulic actuator for pressurizing the hydraulic actuator. The system may also have a hydraulic accumulator assembly for selectively absorbing energy from the hydraulic actuator or via the hydraulic actuator. The system may also have a first one-way valve configured to provide fluid communication between the hydraulic actuator and the hydraulic accumulator assembly. The first one-way valve may be configured to permit a flow of fluid through the first one-way valve from the hydraulic actuator to the hydraulic accumulator assembly. The first one-way valve may also be configured to block a flow of fluid through the first one-way valve from the hydraulic accumulator assembly to the hydraulic actuator.

Claims

1-15. -15. (canceled)

16. A system for recovering energy from a hydraulic actuator, the system comprising:

a hydraulic actuator;

a source of hydraulic pressure in fluid communication with the hydraulic actuator for pressurizing the hydraulic actuator;

a hydraulic accumulator assembly for selectively absorbing energy from the hydraulic actuator or via the hydraulic actuator;

a first one-way valve configured to provide fluid communication between the hydraulic actuator and the hydraulic accumulator assembly, the first one-way valve configured to permit a flow of fluid through the first one-way valve from the hydraulic actuator to the hydraulic accumulator assembly, and the first one-way valve configured to block a flow of fluid through the first one-way valve from the hydraulic accumulator assembly to the hydraulic actuator; and

an overcenter valve for selectively draining fluid from the hydraulic actuator via the overcenter valve, the overcenter valve having an open position and a closed position, the overcenter valve in the open position permitting the draining of fluid from the hydraulic actuator via the overcenter valve, and the overcenter valve in the closed position blocking the draining of fluid from the hydraulic actuator via the overcenter valve, the overcenter valve comprising a biasing member biasing the overcenter valve to the closed position, and the overcenter valve having a pressure-actuatable actuator configured to bias the overcenter valve to the open position.

17. The system according to claim 16, further comprising a hydraulically actuatable control mechanism configured to selectively apply, based at least on a hydraulic pressure in the hydraulic accumulator assembly, a hydraulic pressure on the pressure-actuatable actuator of the overcenter valve.

18. The system according to claim 17, wherein the hydraulically actuatable control mechanism comprises a pressure-actuatable control valve, wherein the pressure-actuatable actuator of the overcenter valve is selectively fluidly connected with at least one of the hydraulic actuator and the source of hydraulic pressure via the pressure-actuatable control valve.

19. The system according to claim 18, wherein the pressure-actuatable control valve comprises a first pressure-actuatable actuator fluidly connected with the hydraulic actuator and configured to bias the pressure-actuatable control valve to a first position, wherein when the pressure-actuatable control valve is in the first position the pressure-actuatable actuator of the overcenter valve is fluidly connected with the hydraulic actuator via the pressure-actuatable control valve.

20. The system according to claim 18, wherein the pressure-actuatable control valve comprises a second pressure-actuatable actuator selectively fluidly connected with the hydraulic accumulator assembly and configured to bias the pressure actuatable control valve to a second position, wherein when the pressure-actuatable control valve is in the second position the pressure-actuatable control valve interrupts a fluid connection between the pressure-actuatable actuator of the overcenter valve and the hydraulic actuator via the pressure-actuatable control valve.

21. The system according to claim 16, further comprising at least one of:

a telescopic boom, a lifting mechanism, a tilting mechanism, or a winching mechanism, wherein the hydraulic actuator is configured to actuate the telescopic boom, the lifting mechanism, the tilting mechanism, or the winching mechanism.

22. The system according to claim 16, further comprising a first energy recovery control valve selectively fluidly connecting the hydraulic accumulator assembly with the hydraulic actuator, the first energy recovery control valve having an open position and a closed position, the first energy recovery control valve in the open position permitting a flow of fluid between the hydraulic actuator and the hydraulic accumulator assembly through the first energy recovery control valve, and the first energy recovery control valve in the closed position fluidly isolating the hydraulic accumulator assembly from the hydraulic actuator, wherein the first energy recovery control valve is configured as a pressure-actuatable valve, the first energy recovery control valve comprising a first pressure-actuatable actuator in fluid communication with the hydraulic actuator and configured to bias the first energy recovery control valve to the closed position, and the first energy recovery control valve comprising a second pressure-actuatable actuator fluidly connected with or selectively fluidly connected with the hydraulic accumulator assembly and configured to bias the first energy recovery control valve to the open position.

23. The system according to claim 22, wherein the first energy recovery control valve comprises a biasing member, the biasing member of the first energy recovery control valve configured to bias the first energy recovery control valve to the open position.

24. The system according to claim 22, wherein the first pressure-actuatable actuator of the first energy recovery control valve, and at least one of the second pressure-actuatable actuator of the first energy recovery control valve and the biasing member of the first energy recovery control valve are configured such that the first energy recovery control valve is switched to the open position if a pressure difference Δ

p=p₁−

p₂ between a closing pressure p₁ acting on the first pressure-actuatable actuator and biasing the first energy recovery control valve to the closed position and an opening pressure p₂ acting on the second pressure-actuatable actuator and biasing the first energy recovery control valve to the open position is smaller than a predetermined pressure difference, wherein the predetermined pressure difference is between 2 bar and 20 bar.

25. The system according to claim 16, wherein the hydraulic actuator comprises a first fluid port and a second fluid port, wherein the pressure-actuatable actuator of the overcenter valve is fluidly connected with or selectively fluidly connected with the first fluid port of the hydraulic actuator, and wherein the pressure-actuatable actuator of the overcenter valve is fluidly connected with or selectively fluidly connected with the second fluid port of the hydraulic actuator.

26. The system according to claim 16, comprising a second one-way valve configured to provide fluid communication between a first fluid port of the overcenter valve and a second fluid port of the overcenter valve, the second one-way valve configured to permit a flow of fluid to bypass the overcenter valve via the second one-way valve toward the hydraulic actuator, and the second one-way valve configured to block the draining of fluid from the hydraulic actuator via the second one-way valve.

27. The system according to claim 16, wherein the hydraulic actuator comprises a first fluid port and a second fluid port, and wherein the hydraulic accumulator assembly and the overcenter valve are fluidly connected with or selectively fluidly connected with the same fluid port of the hydraulic actuator.

28. The system according to any one of claim 22, further comprising a second energy recovery control valve configured to selectively fluidly connect the hydraulic accumulator assembly with at least one of a fluid port of the first energy recovery control valve and the second pressure-actuatable actuator of the first energy recovery control valve.

29. The system according to claim 16, further comprising at least one of a hydraulic pump and a hydraulic motor, wherein the hydraulic accumulator assembly is selectively fluidly connected with at least one of the hydraulic pump and the hydraulic motor.

30. The system according to claim 16, wherein the source of hydraulic pressure includes a hydraulic pump.

31. The system according to claim 16, wherein the hydraulic actuator comprises at least one of a hydraulic cylinder and a hydraulic motor.

32. A method of operating a system for recovering energy from a hydraulic actuator, comprising the steps:

providing a system for recovering energy from a hydraulic actuator, the system comprising;

a hydraulic actuator,

a source of hydraulic pressure in fluid communication with the hydraulic actuator for pressurizing the hydraulic actuator,

a hydraulic accumulator assembly for selectively absorbing energy from the hydraulic actuator or via the hydraulic actuator,

a first one-way valve configured to provide fluid communication between the hydraulic actuator and the hydraulic accumulator assembly, the first one-way valve configured to permit a flow of fluid through the first one-way valve from the hydraulic actuator to the hydraulic accumulator assembly, and the first one-way valve configured to block a flow of fluid through the first one-way valve from the hydraulic accumulator assembly to the hydraulic actuator, and

an overcenter valve for selectively draining fluid from the hydraulic actuator via the overcenter valve, the overcenter valve having an open position and a closed position, the overcenter valve in the open position permitting the draining of fluid from the hydraulic actuator via the overcenter valve, and the overcenter valve in the closed position blocking the draining of fluid from the hydraulic actuator via the overcenter valve, the overcenter valve comprising a biasing member biasing the overcenter valve to the closed position, and the overcenter valve having a pressure-actuatable actuator configured to bias the overcenter valve to the open position; and

if a pressure difference Δ

p=p_act−

p_accu between a hydraulic pressure p_act in the hydraulic actuator and a hydraulic pressure p_accu in the hydraulic accumulator assembly is smaller than a predetermined pressure difference and if a movable member of the hydraulic actuator is intended to be moved, fluidly connecting the hydraulic accumulator assembly with the hydraulic actuator and displacing fluid from the hydraulic actuator to the hydraulic accumulator assembly so that the hydraulic accumulator assembly absorbs energy from the hydraulic actuator.