Leveling system for lift device

• US 10,221,055 B2
• Filed: 04/07/2017
• Issued: 03/05/2019
• Est. Priority Date: 04/08/2016
• Status: Active Grant

• Current Assignee: Oshkosh Corporation
• Original Assignee: Oshkosh Corporation
• Inventors: Hao, JiHong, Puszkiewicz, Ignacy
• Primary Examiner(s): Beck, Karen
• Application Number:
  US15/482,621
• Publication Number:
  US 20170291805A1
• Time in Patent Office: 697 Days
• 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 21/007 means for adjusting the wheel inclination
• CPC Class Codes: B60G 2202/413 Hydraulic actuator
• CPC Class Codes: B60G 2300/022 Fork lift trucks, Clark
• CPC Class Codes: B60G 2400/0511 Roll angle
• CPC Class Codes: B60G 2400/0512 Pitch angle
• CPC Class Codes: B60G 2400/252 vertical
• CPC Class Codes: B60G 2400/60 Load
• CPC Class Codes: B60G 2500/30 Height or ground clearance
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/014 Pitch; Nose dive
• CPC Class Codes: B60G 9/02 the axle or housing being pivotally mounted on the vehicle , e.g. the pivotal axis being parallel to the longitudinal axis of the vehicle B60G9/003 takes precedence
• CPC Class Codes: B60P 1/34 the other movement being raising or lowering
• CPC Class Codes: B60P 3/125 by supporting only part of the vehicle, e.g. front- or rear-axle
• CPC Class Codes: B66C 23/54 with pneumatic or hydraulic motors, e.g. for actuating jib-cranes on tractors
• CPC Class Codes: B66C 9/00 Travelling gear incorporated in or fitted to trolleys or cranes for floor-to-roof stacking devices B66F9/072; for dredgers E02F
• CPC Class Codes: B66F 11/04 for movable platforms or cabins, e.g. on vehicles, permitting workmen to place themselves in any desired position for carrying out required operations Working platforms on fork-lift trucks B66F9/127; vehicle aspects of service vehicles B60P3/14; platforms for cleaning windows A47L3/02; devices for rescuing persons from buildings A62B1/02; liftable or lowerable platforms for use on ladders E06C7/16; maintenance travellers for bridges E01D19/10; scaffolds on an extensible sub-structure E04G1/22
• CPC Class Codes: B66F 11/044 Working platforms suspended from booms
• CPC Class Codes: B66F 13/00 Common constructional features or accessories
• CPC Class Codes: B66F 17/006 for working platforms
• CPC Class Codes: B66F 5/04 : with fluid-pressure-operated lifting gear
• CPC Class Codes: B66F 9/00 : Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes mobile or transportable lifts in, or associated with, buildings and specially adapted to be shifted from one part of a building or other structure to another part or to another building or structure B66B9/16; cranes B66C
• CPC Class Codes: B66F 9/065 : non-masted mobile jacks of the garage type mounted on wheels or rollers B66F5/00
• CPC Class Codes: B66F 9/0655 : with a telescopic boom
• CPC Class Codes: B66F 9/07586 : Suspension or mounting of wheels on chassis
• CPC Class Codes: E01B 27/17 : combined with means for lifting, levelling or slewing the track
• CPC Class Codes: E02F 9/02 : Travelling-gear, e.g. associated with slewing gears drives therefor E02F9/20; for motor vehicles B60B, B60G; undercarriages for locomotives or railroad cars B61F; track-laying vehicles B62D; for cranes B66C23/18

Abstract

A lift device includes a chassis, a boom pivotally coupled to the chassis, a first leveling assembly pivotally coupled to a first end of the chassis, a second leveling assembly pivotally coupled to an opposing second end of the chassis, and a control system. The first leveling assembly includes a first pair of actuators positioned to facilitate a first pitch adjustment and a first roll adjustment of the first end of the chassis. The second leveling assembly includes a second pair of actuators positioned to facilitate a second pitch adjustment and a second roll adjustment of the opposing second end of the chassis. The control system is configured to (i) actively control the first pair of actuators and the second pair of actuators during a first mode of operation, and (ii) actively control the first pair of actuators and facilitate passive control of the second pair of actuators during a second mode of operation.

Claims

1. A method for controlling a leveling system of a lift device, comprising:

providing a lift device including a chassis having a first end and an opposing second end, a first leveling assembly coupled to the first end of the chassis, and a second leveling assembly coupled to the opposing second end of the chassis, wherein each of the first leveling assembly and the second leveling assembly includes a pair of tractive elements coupled to the chassis that are repositionable relative to the chassis about (i) a longitudinal axis defined by the chassis and (ii) a lateral axis defined by an interface between the chassis and each of the first leveling assembly and the second leveling assembly, respectively, such that (i) the first leveling assembly and the second leveling assembly are configured to facilitate a roll adjustment about the longitudinal axis and (ii) the first leveling assembly and the second leveling assembly are configured to facilitate a pitch adjustment of the first end and the opposing second end of the chassis, respectively, about the lateral axis, and wherein the lift device is operable in a first mode and a second mode;

actively controlling the first leveling assembly and the second leveling assembly during the first mode; and

actively controlling the first leveling assembly and passively controlling the second leveling assembly during the second mode such that the second leveling assembly freely floats.

2. The method of claim 1, further comprising:

receiving operation data from a sensor regarding operation of the lift device; and

actively controlling at least one of the first leveling assembly and the second leveling assembly based on the operation data.

3. The method of claim 2, wherein the operation data is indicative of at least one of a pitch angle of the chassis, a roll angle of the chassis, a displacement of a first pair of actuators of the first leveling assembly, a displacement of a second pair of actuators of the second leveling assembly, a position of a boom of the lift device, and a load on one or more tractive elements of the lift device.

4. The method of claim 1, wherein the second leveling assembly includes one or more valves positioned to facilitate at least one of (i) selectively isolating a second pair of actuators of the second leveling assembly from a high pressure fluid source and (ii) selectively fluidly coupling and decoupling the second pair of actuators.

5. The method of claim 4, further comprising:

engaging the one or more valves during the first mode of operation such that the second pair of actuators fluidly decouple from each other; and

engaging the one or more valves during the second mode of operation such that the second pair of actuators fluidly couple together.

6. The method of claim 5, wherein the first mode of operation includes at least one of a transport mode, a calibration mode, and a boom operation mode.

7. The method of claim 6, wherein the first mode of operation includes the transport mode, the method further comprising actively controlling a first pair of actuators of the first leveling assembly and the second pair of actuators to reduce an overall height of the lift device to a target height in response to the transport mode being activated.

8. The method of claim 6, wherein the first mode of operation includes the calibration mode, the method further comprising:

actively controlling a first pair of actuators of the first leveling assembly, the second pair of actuators, and a boom of the lift device to return the first pair of actuators, the second pair of actuators, and the boom to a nominal position in response to the calibration mode being activated; and

zeroing out a sensor of the lift device.

9. The method of claim 6, wherein the first mode of operation includes the boom operation mode, the method further comprising actively controlling a first pair of actuators of the first leveling assembly and the second pair of actuators to maintain the chassis level while a boom of the lift device is being operated in the boom operation mode.

10. The method of claim 6, wherein the second mode of operation includes a driving mode.

11. The method of claim 1, wherein the lift device includes a drive system having at least one of:

a plurality of steering actuators, each of the plurality of steering actuators associated with a respective tractive element of the lift device; and

a plurality of drive actuators, each of the plurality of drive actuators associated with a respective tractive element of the lift device.

12. The method of claim 11, further comprising controlling the at least one of the plurality of steering actuators and the plurality of drive actuators to at least one of independently drive and independently steer each tractive element.

13. The method of claim 12, further comprising limiting operation of at least one of the plurality of steering actuators, the plurality of drive actuators, and a boom of the lift device during the first mode of operation.

14. A method for controlling a leveling system of a lift device, comprising:

providing a lift device including a chassis having a first end and an opposing second end, a first leveling assembly coupled to the first end of the chassis, and a second leveling assembly coupled to the opposing second end of the chassis, wherein the first leveling assembly and the second leveling assembly are configured to facilitate a roll adjustment and a pitch adjustment of the first end and the opposing second end of the chassis, respectively, wherein the second leveling assembly includes one or more valves positioned to facilitate at least one of (i) selectively isolating a second pair of actuators of the second leveling assembly from a high pressure fluid source and (ii) selectively fluidly coupling and decoupling the second pair of actuators, wherein the lift device is operable in a first mode and a second mode, and wherein the first mode of operation includes a boom operation mode;

engaging the one or more valves during the boom operation mode such that the second pair of actuators fluidly decouple from each other;

actively controlling a first pair of actuators of the first leveling assembly and the second pair of actuators of the second leveling assembly to maintain the chassis level while a boom of the lift device is being operated in the boom operation mode;

selectively limiting a speed of the lift device during the boom operation mode;

engaging the one or more valves during the second mode of operation such that the second pair of actuators fluidly couple together; and

actively controlling the first leveling assembly and passively controlling the second leveling assembly during the second mode such that the second leveling assembly freely floats.

15. A method for controlling a leveling system of a lift device, the method comprising:

providing a lift device including a chassis having a first end and an opposing second end, a first actuator coupled to the first end of the chassis, a second actuator coupled to the first end of the chassis, a third actuator coupled to the opposing second end of the chassis, and a fourth actuator coupled to opposing the second end of the chassis, wherein each of the first actuator, the second actuator, the third actuator, and the fourth actuator couples a tractive element to the chassis;

fluidly coupling at least two of the first actuator, the second actuator, the third actuator, and the fourth actuator such that the at least two of the first actuator, the second actuator, the third actuator, and the fourth actuator freely float; and

fluidly decoupling and actively controlling the at least two to the first actuator, the second actuator, the third actuator, and the fourth actuator;

wherein the tractive elements are repositionable relative to (i) a longitudinal axis defined by the chassis and (ii) a lateral axis defined by the chassis such that the first actuator, the second actuator, the third actuator, and the fourth actuator are configured to facilitate a roll adjustment about the longitudinal axis and a pitch adjustment about the lateral axis.