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US-20260125257-A1 - TURNTABLE LEVELING SYSTEM FOR A MOBILE ELEVATING WORK PLATFORM

US20260125257A1US 20260125257 A1US20260125257 A1US 20260125257A1US-20260125257-A1

Abstract

A mobile elevating work platform includes a chassis, a slew bearing, a turntable, a lift system, and a turntable leveling system. The turntable leveling system is positioned above the slew bearing and supports the lift system. The turntable leveling system includes a baseplate, and a bracket. The baseplate extends above the slew bearing. The bracket is rotatably coupled to the baseplate and is configured to tilt relative to the baseplate about an axis extending parallel with the baseplate.

Inventors

  • Wenton S. Miller
  • Eric Hackenberg

Assignees

  • OSHKOSH CORPORATION

Dates

Publication Date
20260507
Application Date
20251229

Claims (20)

  1. 1 . A mobile elevating work platform, comprising: a chassis; a slew bearing supported by the chassis; a turntable positioned above the slew bearing and configured to rotate about the slew bearing; a lift system positioned on the turntable and configured to rotate with the turntable relative to the chassis about the slew bearing; and a turntable leveling system positioned above the slew bearing and supporting the lift system, the turntable leveling system comprising: a baseplate extending above the slew bearing and defining the turntable; and a bracket rotatably coupled to the baseplate and configured to tilt relative to the baseplate about an axis extending parallel with the baseplate.
  2. 2 . The mobile elevating work platform of claim 1 , wherein the lift system includes an articulating boom, and wherein a lower lift arm of the articulating boom is rotatably coupled to the bracket.
  3. 3 . The mobile elevating work platform of claim 2 , wherein a lift actuator is coupled to the bracket and is configured to rotate the lower lift arm about a second axis perpendicular to the axis.
  4. 4 . The mobile elevating work platform of claim 1 , wherein the turntable leveling system is further comprising: a first actuator and a second actuator are configured to adjust an orientation of the bracket relative to the baseplate and are further configured to adjust a height of the lift system.
  5. 5 . The mobile elevating work platform of claim 4 , wherein each of the first actuator and the second actuator include a lift cylinder and a tilt cylinder, wherein the tilt cylinder is configured to adjust the orientation of the bracket relative to the baseplate and the lift cylinder is configured to adjust the height of the lift system.
  6. 6 . The mobile elevating work platform of claim 4 , wherein the first actuator and the second actuator are coupled to the baseplate at a first end and coupled to a lower lift arm of the lift system at a second end.
  7. 7 . The mobile elevating work platform of claim 6 , wherein the lower lift arm includes laterally and rearwardly extending wings that define eyelets that receive second ends of each of the first actuator and the second actuator.
  8. 8 . The mobile elevating work platform of claim 1 , wherein the lift system includes a platform assembly configured to be raised away from the chassis.
  9. 9 . The mobile elevating work platform of claim 1 , wherein the bracket is supported by lugs extending upwardly away from the baseplate, the lugs supporting a pivot pin about which the bracket is configured to rotate.
  10. 10 . A mobile elevating work platform, comprising: a chassis; a slew bearing supported by the chassis; a turntable positioned above the slew bearing and configured to rotate about the slew bearing; a lift system positioned on the turntable and configured to rotate with the turntable relative to the chassis about the slew bearing; and a turntable leveling system positioned above the slew bearing and supporting the lift system, the turntable leveling system comprising: a bracket defining an array of pivot points; and a baseplate coupled to the bracket and configured to rotate about an axis defined by at least one of the array of pivot points.
  11. 11 . The mobile elevating work platform of claim 10 , wherein the lift system includes an articulating boom, and wherein a lower lift arm of the articulating boom is rotatably coupled to the baseplate.
  12. 12 . The mobile elevating work platform of claim 10 , wherein the turntable leveling system is further comprising: a first actuator and a second actuator angled outwardly away from the bracket at an angle of between 45 degrees and 160 degrees.
  13. 13 . The mobile elevating work platform of claim 10 , wherein the bracket has a generally triangular shape, and wherein the array of pivot points are positioned adjacent vertices of the generally triangular shape.
  14. 14 . The mobile elevating work platform of claim 13 , wherein the baseplate is coupled to the bracket adjacent an uppermost vertex of the bracket.
  15. 15 . The mobile elevating work platform of claim 10 , wherein the bracket is positioned between the baseplate and the slew bearing.
  16. 16 . The mobile elevating work platform of claim 15 , wherein flanges are formed on the baseplate, and wherein the turntable leveling system further is comprising a first actuator and a second actuator that are each coupled to one of the flanges.
  17. 17 . A mobile elevating work platform, comprising: a chassis; a slew bearing supported by the chassis; a turntable positioned above the slew bearing and configured to rotate about the slew bearing; and a lift system positioned on the turntable and configured to rotate with the turntable relative to the chassis about the slew bearing; and a turntable leveling system positioned above the slew bearing and supporting the lift system, the turntable leveling system comprising: a baseplate extending above the slew bearing and defining the turntable; a bracket rotatably coupled to the baseplate and configured to tilt relative to the baseplate about a first axis extending parallel with the baseplate; a first actuator positioned on and coupled to a first side of the bracket; a second actuator positioned on and coupled to a second side of the bracket; and a third actuator coupled to the bracket, wherein extension of each of the first actuator and the second actuator causes the bracket to rotate about the first axis, and wherein extension of the third actuator causes a portion of the lift system to rotate about a second axis perpendicular to the first axis.
  18. 18 . The mobile elevating work platform of claim 17 , wherein extending of the first actuator and extension of the second actuator causes a lower lift arm of the lift system to rotate upwardly away from the bracket.
  19. 19 . The mobile elevating work platform of claim 18 , wherein retracting of the first actuator and retraction of the second actuator causes the lower lift arm of the lift system to rotate downwardly toward the bracket.
  20. 20 . The mobile elevating work platform of claim 17 , wherein each of the first actuator and the second actuator are two-stage actuators.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation of U.S. patent application Ser. No. 17/563,719, filed Dec. 28, 2021, which claims the benefit of U.S. Provisional Ser. No. 63/131,592, filed Dec. 29, 2020, which is incorporated herein by reference in its entirety. BACKGROUND Boom lifts and other mobile elevating work platforms (MEWPs) are frequently used outdoors to accomplish tasks at different elevations. In some instances, the MEWPs will encounter an uneven ground surface, which may cause a chassis of the MEWP to lean about a roll axis of the MEWP. As the lean of the MEWP becomes more severe, the center of gravity on the MEWP shifts toward one of the wheels. An allowable working height of the platform on the MEWP decreases as the lean becomes more severe. The moment generated by the platform at a normal maximum working height may otherwise violate a necessary factor of safety for the balancing force of a counterweight on the MEWP. Accordingly, the uneven ground surface can prevent or restrict a traditional MEWP from performing tasks in certain locations or terrains. SUMMARY One exemplary embodiment relates to a mobile elevating work platform (e.g., a boom). The MEWP includes a chassis, a slew bearing, a turntable, a lift system, and a turntable leveling system. The chassis supports a plurality of wheels. The slew bearing is supported by the chassis. The turntable is positioned above the slew bearing and is configured to rotate about the slew bearing, relative to the chassis. The lift system is positioned on the turntable and is configured to rotate with the turntable relative to the chassis about the slew bearing. The turntable leveling system is positioned above the slew bearing and supports the lift system. The turntable leveling system includes a baseplate, and a bracket. In some examples, the turntable is the baseplate within the turntable leveling system. The baseplate extends above the slew bearing. The bracket is rotatably coupled to the baseplate and is configured to tilt relative to the baseplate about an axis extending parallel with the baseplate. Another exemplary embodiment relates to a mobile elevating work platform (e.g., a boom). The MEWP includes a chassis, a slew bearing, a turntable, a lift system, and a turntable leveling system. The slew bearing is supported by the chassis. The turntable is positioned above the slew bearing and is configured to rotate about the slew bearing, relative to the chassis. The lift system is positioned on the turntable and is configured to rotate with the turntable relative to the chassis about the slew bearing. The turntable leveling system is positioned above the slew bearing and supports the lift system. The turntable leveling system includes a baseplate, a bracket, a first actuator, and a second actuator. The bracket defines an array of pivot points. The baseplate is coupled to the bracket and is configured to rotate about an axis defined by at least one of the array of pivot points. Another exemplary embodiment relates to a mobile elevating work platform (e.g., a boom). The MEWP includes a chassis, a slew bearing, a turntable, a lift system, and a turntable leveling system. The chassis supports a plurality of wheels. The slew bearing is supported by the chassis. The turntable is positioned above the slew bearing and is configured to rotate about the slew bearing, relative to the chassis. The lift system is positioned on the turntable and is configured to rotate with the turntable relative to the chassis about the slew bearing. The turntable leveling system is positioned above the slew bearing and supports the lift system. The turntable leveling system includes a baseplate, a bracket, a first actuator, a second actuator, and a third actuator. The baseplate extends above the slew bearing and defines the turntable. The bracket is rotatably coupled to the baseplate and is configured to tilt relative to the baseplate about an axis extending parallel with the baseplate. The first actuator is positioned on and coupled to a first side of the bracket and the second actuator is positioned on and coupled to a second side of the bracket. The third actuator is coupled to the bracket. Extension of each of the first actuator and the second actuator causes the bracket to rotate about the axis. Extensions of the third actuator causes a portion of the lift system to rotate about a second axis perpendicular to the first axis. The invention is capable of other embodiments and of being carried out in various ways. Alternative exemplary embodiments relate to other features and combinations of features as may be recited herein. BRIEF DESCRIPTION OF THE FIGURES The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements, in which: FIG. 1 is a front perspective view of a boom lift, according to an exemplary embodiment;