EP-4737650-A1 - A SLEW APPARATUS OF A WORKING MACHINE

EP4737650A1EP 4737650 A1EP4737650 A1EP 4737650A1EP-4737650-A1

Abstract

A slew apparatus of a working machine comprises a slew frame, an electric motor mounting element mounted to the slew frame and an electric motor mounted to the electric motor mounting element for driving the slew apparatus in rotation, the electric motor having a drive axis defining an axial direction and a radial direction normal to the axis, and a drive output shaft extending from one axial end thereof, the electric motor mounting element comprising: a body configured to receive the electric motor; and at least three mounting legs; each leg projecting radially from the body so as to define a free end spaced from the body and each leg defining a mounting portion, at the respective free end thereof, and configured to effect fastening of the electric motor mounting element to the slew frame so as to mount the electric motor to the slew frame, whereby each mounting portion is spaced radially outwardly from the perimeter of the electric motor when viewed in the axial direction thereof.

Inventors

DAVIES, Aaron
PARKER, BENJAMIN
STACEY, THOMAS

Assignees

J.C. Bamford Excavators Limited

Dates

Publication Date: 20260506
Application Date: 20251030

Claims (15)

A slew apparatus of a working machine comprising a slew frame, an electric motor mounting element mounted to the slew frame and an electric motor mounted to the electric motor mounting element for driving the slew apparatus in rotation, the electric motor having a drive axis defining an axial direction and a radial direction normal to the axis, and a drive output shaft extending from one axial end thereof, the electric motor mounting element comprising: a body configured to receive the electric motor; and at least three mounting legs; each leg projecting radially from the body so as to define a free end spaced from the body and each leg defining a mounting portion, at the respective free end thereof, and configured to effect fastening of the electric motor mounting element to the slew frame so as to mount the electric motor to the slew frame, whereby each mounting portion is spaced radially outwardly from the perimeter of the electric motor when viewed in the axial direction thereof.
A slew apparatus according to claim 1, in which each mounting portion comprises a mounting aperture arranged to receive a fastener to effect fastening of the electric motor mounting element to the slew frame.
A slew apparatus according to claim 1 or 2, in which the legs are substantially equal in radial length or in which the legs have different radial lengths.
A slew apparatus according to any preceding claim, in which the legs are respectively evenly spaced about the body when viewed in the axial direction.
A slew apparatus according to any preceding claim, in which the slew apparatus comprises a ring bearing having a ring bearing mounting defining a circumference, the electric motor mounting element being mounted such that the electric motor mounting element body is arranged within the circumference and at least one leg projects radially outside the circumference so that the mounting portion on that leg is outside the circumference.
A slew apparatus according to claim 5, in which more than one of the mounting portions is located outside the circumference.
A slew apparatus according to any preceding claim in which the electric motor mounting element body is generally circular when viewed in the axial direction.
A slew apparatus according to claim 2 or any of claims 3 to 7 when dependent upon claim 2, in which each mounting aperture is surrounded by a collar projecting axially from the leg, the collar having an axial depth less than the thickness of the slew frame.
A slew apparatus according to any preceding claim, in which the electric motor includes a gear apparatus at the drive output end thereof, the gear apparatus being configured to receive the drive output shaft of the electric motor and step down the drive output to a lower revolution, higher torque gear output shaft.
A slew apparatus according to claim 9, in which the gear apparatus comprises a gear lubricant port and the motor is arranged on the electric motor mounting element such that the legs are circumferentially spaced from the port, when viewed in the axial direction.
A slew apparatus according to any preceding claim, in which the body of the electric motor mounting element does not project radially beyond the perimeter of the electric motor, when viewed in the axial direction.
A slew apparatus according to any preceding claim, in which the electric motor has at least one radially projecting portion to receive an electrical or fluid connection port and the motor is arranged on the electric motor mounting element such that the legs are circumferentially spaced from the projecting portion, when viewed in the axial direction, optionally wherein the legs, the lubricant port and the projecting portion are circumferentially spaced from each other, when viewed in the axial direction.
A slew apparatus according to any preceding claim, further comprising: a slew bearing mounted to the slew frame, the slew bearing comprising a ring bearing defining a circumference and a bearing axis, the bearing axis defining an axial direction of the apparatus and a line from the bearing axis to the circumference defining a radial direction of the apparatus; the electric motor having an axial length and a motor diameter which are specified to provide an electric motor rated to drive the slew bearing in rotation; the slew bearing and electric motor assembly being arranged on the slew frame such that the motor drive axis is inside the ring bearing circumference and extends substantially parallel to the axial direction, the motor drive axis being located radially closer to the ring bearing circumference than the ring bearing axis; and the axial length and diameter of the electric motor, and the configuration of the electric motor mounting, being configured such that a space is defined between the radially innermost part of the electric motor and the ring bearing axis.
A slew apparatus according to any of claims 1 to 4, in which the slew apparatus comprises a ring bearing having a ring bearing mounting defining a circumference, the electric motor mounting element being mounted such that the electric motor mounting element body is arranged outside the circumference and at least one leg projects radially inside the circumference so that the mounting portion on that leg is inside the circumference.
A working machine having a cab for an operator and a slew apparatus according to any preceding claim, the cab being arranged above the slew apparatus.

Description

FIELD The field of the disclosure is working machines having a slew apparatus, for example excavators, backhoe loaders, telehandlers, etc. BACKGROUND It is known for certain kinds of working machines to be equipped with a slew apparatus which enables the upper part of the machine, typically including the operator cab and tool platform, to be rotated about a vertical axis of the machine relative to the lower part, which typically includes an undercarriage with wheels, tracks and/or legs. Such apparatus enables a working machine to operate without having to reposition itself. One example of such a machine would be an excavator digging a trench, in which case the excavator can be positioned adjacent to the trench location where it can be secured in place, usually by means of extendable legs, and the operator can then use the excavator shovel to dig the trench and use the slew apparatus to rotate the shovel and cab relative to the excavator undercarriage to dump earth removed from the trench in a location spaced from the trench. In another example, a telehandler can be positioned in one location, for example to lift a load from high shelving, then rotated using the slew to allow the telehandler to be driven along a path between shelving in order to deliver the load to another location. Those are two, non-limiting examples of many known applications of slew apparatuses on working machines. Existing slew apparatuses typically comprise a rotating slew frame, which carries all of the upper parts of the working machine, e.g. operator cab and tool platform, which frame is rotatably mounted to the lower part of the working machine. The lower part of the vehicle has a ring gear with inwardly projecting gear teeth and the rotating frame has a ring bearing arranged outside the ring gear and a planet gear arranged inside the ring gear, with teeth that interdentate with the ring gear teeth. The planet gear is usually driven in rotation by a hydraulic motor, enabling the rotating frame to be driven in rotation relative to the ring gear. In another arrangement, the ring gear has outwardly projecting gear teeth and then the planet gear is arranged to the exterior of the ring gear. There is an increasing inclination in the field of working machines to replace hydraulic motors with electric motors. Integration of electric motors presents new mounting and packaging challenges, which the present teachings seek to address. SUMMARY The present teachings provide a slew apparatus of a working machine according to the appended claims. An aspect of the teachings provides a slew apparatus of a working machine comprising a slew frame, an electric motor mounting element mounted to the slew frame and an electric motor mounted to the electric motor mounting element for driving the slew apparatus in rotation. The electric motor has a drive axis defining an axial direction and a radial direction normal to the axis, and a drive output shaft extending from one axial end thereof. The electric motor mounting element comprises a body configured to receive the electric motor and at least three mounting legs. Each leg projects radially from the body so as to define a free end spaced from the body and each leg defines a mounting portion, at the respective free end thereof, and configured to effect fastening of the electric motor mounting element to the slew frame so as to mount the electric motor to the slew frame. Each mounting portion is spaced radially outwardly from the perimeter of the electric motor when viewed in the axial direction thereof. By providing a three-legged mounting element where the legs project radially from the electric motor body, the motor can be mounted to the frame so as to resist the torque reaction created when it drives the frame in rotation and the projection of the legs facilitates access to mount (and demount) the motor to the frame. Each mounting portion may comprise a mounting aperture arranged to receive a fastener to effect fastening of the electric motor mounting element to the slew frame. That allows bolts to pass through the mounting apertures to secure the motor to the frame. The legs may be substantially equal in radial length. In that way, the legs resist the torque reaction created when the motor drives the frame in rotation equally. Alternatively, the legs may have different radial lengths. Different leg length allows the selection of different radial locations for the mounting apertures which may be necessary on particular machines, e.g. to allow for the placement of other components on the frame. The legs may be respectively evenly spaced about the body when viewed in the axial direction. That ensures an even distribution of the force required to resist the reactive torque moment created when the motor drives the frame in rotation. The slew apparatus may comprise a ring bearing having a ring bearing mounting defining a circumference, the electric motor mounting element being mounted such that the electric