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EP-4741585-A2 - LIFT ARM ARRANGEMENTS FOR POWER MACHINES

EP4741585A2EP 4741585 A2EP4741585 A2EP 4741585A2EP-4741585-A2

Abstract

The present invention discloses a power machine for movably operating an implement, the power machine comprising: a frame that supports an operator station; an electrical power source supported by the frame; and a lift arm structure supported by the frame, the lift arm structure including: a lift arm extending along a lateral side of the frame, with a proximal end of the lift arm movably secured to the frame at a rear portion of the frame and a distal end of the lift arm including a tilt actuator pocket; an implement carrier movably secured to the distal end of the lift arm lower beam; and an electrical tilt actuator, secured to the lift arm within the tilt actuator pocket, the electrical tilt actuator being configured to be controllably extended and retracted to change an attitude of the implement carrier, wherein the electrical tilt actuator includes an electrical motor and an extendable portion configured as a ball screw, the electrical tilt actuator being secured to the lift arm and extending along a laterally exterior side of the frame, wherein the electrical motor is in a fold-back motor configuration relative to the extendable portion, located rearward of the extendable portion and shielded by the lift arm along a laterally exterior side of the electrical motor, and wherein with the lift arm structure in a fully lowered orientation, a front wall of the tilt actuator pocket shields at least part of a front side of the extendable portion.

Inventors

  • The designation of the inventor has not yet been filed

Assignees

  • Doosan Bobcat North America, Inc.

Dates

Publication Date
20260513
Application Date
20220902

Claims (8)

  1. A power machine (300) for movably operating an implement, the power machine comprising: a frame (310) that supports an operator station (355); an electrical power source (335) supported by the frame (310); and a lift arm structure (330) supported by the frame (310), the lift arm structure including: a lift arm extending along a lateral side of the frame, with a proximal end of the lift arm movably secured to the frame at a rear portion of the frame and a distal end of the lift arm including a tilt actuator pocket (380); an implement carrier (372) movably secured to the distal end of the lift arm lower beam (339C); and an electrical tilt actuator (373), secured to the lift arm (332) within the tilt actuator pocket (380), the electrical tilt actuator (373) being configured to be controllably extended and retracted to change an attitude of the implement carrier (372), wherein the electrical tilt actuator (373) includes an electrical motor (374) and an extendable portion configured as a ball screw (375), the electrical tilt actuator (373) being secured to the lift arm and extending along a laterally exterior side of the frame, wherein the electrical motor (374) is in a fold-back motor configuration relative to the extendable portion, located rearward of the extendable portion and shielded by the lift arm (332) along a laterally exterior side of the electrical motor (374), and wherein with the lift arm structure (330) in a fully lowered orientation, a front wall (387) of the tilt actuator pocket (380) shields at least part of a front side of the extendable portion.
  2. The power machine of claim 1, wherein the lift arm comprises a main beam and a lower beam, and wherein the tilt actuator pocket is formed within the lower beam of the lift arm that is coupled to and extends downward from the main beam of the lift arm at the distal end of the lift arm.
  3. The power machine of claim 2, wherein the lower beam includes an inner leg and a lateral jog that connects the main beam with the inner leg; and wherein the electric tilt actuator extends substantially along a laterally exterior side of the inner leg.
  4. The power machine of any preceding claim, wherein the electrical tilt actuator is secured to the lift arm by a pinned connection, which is preferably a clevis-joint connection, within a proximal end of the tilt actuator pocket.
  5. The power machine of claim 4, wherein a support plate of the clevis joint extends proud of the tilt-actuator portion of the lift arm to a laterally interior side of the lift arm.
  6. The power machine of any of claims 2 to 5, wherein the electrical tilt actuator is laterally aligned with a main beam of the lift arm.
  7. The power machine of claim 6, wherein a portion of the electrical tilt actuator extends to a laterally interior side of the main beam.
  8. The power machine of claim 4, wherein the clevis-joint connection between the electrical tilt actuator and the lift arm is aligned, in a front-to-back direction of the power machine, with a lateral side wall of the main beam.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to provisional patent applications no. 63/292,679, filed December 22, 2021, and no. 63/240,151, filed September 2, 2021, both of which are incorporated herein by reference. BACKGROUND This disclosure is directed towards lift arms. More specifically, the present disclosure is directed towards an electrically powered lift arm for a power machine that operates in whole or in part under electrical power. Power machines, for the purposes of this disclosure, include any type of machine that generates power for the purpose of accomplishing a particular task or a variety of tasks. One type of power machine is a work vehicle. Work vehicles, such as loaders, are generally self-propelled vehicles that have a work device, such as a lift arm (although some work vehicles can have other work devices) that can be manipulated to perform a work function. Work vehicles include loaders, excavators, utility vehicles, tractors, and trenchers, to name a few examples. Conventional power machines can include hydraulic systems and related components that are configured to use output from a power source (e.g., an internal combustion engine) to perform different work functions. More specifically, hydraulic motors may be configured to power movement of a power machine, and hydraulic actuators (e.g., hydraulic cylinders) may be used to move a lift arm structure attached to the power machine, to tilt or otherwise move an implement connected to the lift arm structure, or execute other operations. The discussion above is merely provided for general background infonnation and is not intended to be used as an aid in determining the scope of the claimed subject matter. SUMMARY Some examples of the present disclosure provide a power machine for movably operating an implement. The power machine can include a main frame (e.g., that supports an operator station) and a lift arm structure. The lift arm structure can include a lift arm extending along a lateral side of the frame. A proximal end of the lift arm can be movably secured to the frame at a rear portion of the frame. The power machine can further include an implement carrier movably secured to the distal end of the lift arm, and an electrical lift actuator. In some cases, an electrical lift actuator can be secured at a first end to the rear portion of a frame and at a second end to a lift arm. The electrical lift actuator can be disposed within a lift actuator pocket defined by the frame and can be configured to be controllably extended and retracted to raise and lower the lift arm. Some examples of the present disclosure provide a lift arm structure for a power machine with a frame. The lift ann structure can include a lift ann and an electrical lift actuator. The lift arm can be configured to be movably secured to the frame to extend along a lateral side of the frame. In some cases, an electrical lift actuator can be secured to a lift arm within a pocket defined by the lift arm and can be configured to extend and retract between the lift arm and a frame of a power machine to raise and lower the lift ann. In some cases, an electrical lift actuator can be secured at a first end to a frame and at a second end to a main beam, within a pocket defined in the main beam. Some examples of the present disclosure provide a lift ann structure for a power machine having a frame. The lift arm structure can include a main beam and a lift actuator. The main beam can extend along a lateral side of the power machine from a first end proximate a rear of the power machine to a second end proximate a front of the power machine. Some examples of the present disclosure provide a power machine that can include a frame (e.g., that supports an operator station), a lift arm movably secured to the frame to extend along a lateral side of the frame, an electrical tilt actuator, an electrical lift actuator, and a power source that can be configured to power the electrical tilt actuator and the electrical lift actuator. The electrical tilt actuator can be secured to the lift ann and an implement carrier and can be configured to be controllably extended and retracted to change an attitude of an implement carrier. The electrical lift actuator can be secured at a first end to the frame (e.g., within a first pocket) and at a second end to the lift arm (e.g. within a second pocket), the electrical lift actuator, and can be configured to be controllably extended and retracted to raise and lower the lift arm. Some examples of the present disclosure provide a power machine for movably operating an implement. The power machine can include a frame (e.g., that supports an operator station), a lift arm structure supported by the frame. The lift arm structure can include: a lift arm extending along a lateral side of the frame, with a proximal end of the lift arm movably secured to the frame at a rear portion of the frame; an implement carrier movably secured t