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EP-4738666-A1 - ACTUATOR

EP4738666A1EP 4738666 A1EP4738666 A1EP 4738666A1EP-4738666-A1

Abstract

Provided is a technique for identifying a lubrication state of a contact unit in an actuator (10) including a motor (14) and a speed reducer. An actuator (10) including a motor (14) and a speed reducer (16), includes: a contact unit (60A to 60F) including a plurality of contact members, in which during an operation of the actuator (10), the contact members adjacent to each other come into contact with each other with relative movement; a plurality of energization members (66A, 66B) provided separately from the contact unit (60A to 60F) and configured to cause an electric current to flow through an energization path (64) configured by a plurality of actuator constituent members via a contact location between the plurality of contact members; and a measurement unit (62) configured to measure a lubrication state between the plurality of contact members in the contact unit (60A to 60F) by causing an electric current to flow through the energization path (64).

Inventors

  • BOCHMANN, Max
  • KEHL, Jan Hendrik

Assignees

  • Sumitomo Heavy Industries, LTD.

Dates

Publication Date
20260506
Application Date
20251020

Claims (10)

  1. An actuator (10) that includes a motor (14) and a speed reducer (16), the actuator (10) comprising: a contact unit (60A to 60F) including a plurality of contact members, in which during an operation of the actuator (10), the contact members adjacent to each other come into contact with each other with relative movement; a plurality of energization members (66A, 66B) provided separately from the contact unit (60A to 60F) and configured to cause an electric current to flow through an energization path (64) configured to include a plurality of actuator constituent members via a contact location between the plurality of contact members; and a measurement unit (62) configured to measure a lubrication state between the plurality of contact members in the contact unit (60A to 60F) by causing the electric current to flow through the energization path (64).
  2. The actuator (10) according to claim 1, further comprising: a rotating body (52) that is rotated by a stator (26) and a rotor (28) of the motor (14), wherein the plurality of energization members (66A, 66B) include a first energization member (66A) for inputting the electric current to the rotating body (52) or outputting the electric current from the rotating body (52), and the first energization member (66A) is disposed on a counter load side with respect to the stator (26).
  3. The actuator (10) according to claim 2, wherein the contact unit (60A) serving as a measurement target to be measured by the measurement unit (62) is disposed on a load side with respect to the stator (26).
  4. The actuator (10) according to claim 3, further comprising: a relative rotating body (56A, 56B) that rotates relative to the rotating body (52), wherein the plurality of energization members (66A, 66B) include a second energization member (66B) for inputting the electric current to the relative rotating body (56A, 56B) or outputting the electric current from the relative rotating body (56A, 56B).
  5. The actuator (10) according to claim 4, wherein the second energization member (66B) is disposed on a counter load side with respect to the stator (26).
  6. The actuator (10) according to claim 1, wherein the contact unit (60A to 60F) includes a measurement target unit (60H) that is provided on the energization path (64) and that serves as a measurement target to be measured by the measurement unit(62), and a non-measurement target unit (60I) that is provided on a parallel path (80) that is connected in parallel with the measurement target unit (60H) on the energization path (64) in a case where it is assumed that the actuator constituent member is conductive, and the actuator (10) further comprises an insulating material (82) that blocks a flow of an electric current passing through the parallel path (80) on the energization path (64).
  7. The actuator (10) according to claim 6, wherein the insulating material (82) is configured by at least a part of the non-measurement target unit (60I).
  8. The actuator (10) according to claim 1, wherein the contact unit (60A) serving as a measurement target to be measured by the measurement unit (62) is a gear set or a bearing.
  9. The actuator (10) according to claim 1, wherein the contact unit (60A) serving as a measurement target to be measured by the measurement unit (62) constitutes a part of the speed reducer (16).
  10. The actuator (10) according to claim 1, further comprising: a life estimating unit (76) that predicts a life of the actuator (10), based on the lubrication state measured by the measurement unit (62).

Description

BACKGROUND OF THE INVENTION Field of the Invention The present disclosure relates to an actuator. Description of Related Art Japanese Unexamined Patent Publication No. 2022-142033 discloses an actuator including a motor and a speed reducer. The actuator usually includes a contact unit including a plurality of contact members such as a bearing and a gear set. In the contact unit, during the operation of the actuator, the contact members adjacent to each other can come into contact with each other with relative movement. SUMMARY OF THE INVENTION A lubrication state between the contact members of the contact unit during the operation of the actuator affects various elements such as the life of the actuator. Therefore, it is desirable to be able to identify the lubrication state. However, a technique capable of satisfying such a demand has not yet been proposed for the actuator including a motor and a speed reducer. Therefore, one object of the present disclosure is to provide a technique for identifying a lubrication state of a contact unit in an actuator including a motor and a speed reducer. An actuator according to the present disclosure is an actuator that includes a motor and a speed reducer, the actuator including: a contact unit including a plurality of contact members, in which during an operation of the actuator, the contact members adjacent to each other come into contact with each other with relative movement; a plurality of energization members provided separately from the contact unit and configured to cause an electric current to flow through an energization path configured to include a plurality of actuator constituent members via a contact location between the plurality of contact members; and a measurement unit configured to measure a lubrication state between the plurality of contact members in the contact unit by causing the electric current to flow through the energization path. According to the present disclosure, it is possible to identify a lubrication state of a contact unit in an actuator including a motor and a speed reducer. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side sectional view showing an actuator according to an embodiment.FIG. 2 is an enlarged view of a part of FIG. 1.FIG. 3 is a block diagram showing some functions of the actuator according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION Hereinafter, an embodiment for implementing an actuator according to the present disclosure will be described. Identical or equivalent elements will be denoted by the same reference numerals and the repeated description thereof will be omitted. In each drawing, for convenience of description, the components are appropriately omitted, enlarged, or reduced. The drawings shall be viewed according to the directions of the reference numerals. In the present specification, the notation of "n-th" (n is a natural number) such as "first" and "second" is used only as a formal description for distinguishing a plurality of elements, and does not have any substantial meaning other than that. For example, the notation of "n-th" does not limit the order of each element. In addition, each element with the notation of "n-th" may be present independently without continuity. For example, it is possible that the "second" element may be present without the "first" element being present. FIG. 1 is referred to. An actuator 10 can drive a driven device (not shown) by outputting rotation. The driven device is, for example, at least a part in various machines such as (1) an industrial machine such as a machine tool or a construction machine, (2) a robot such as an industrial robot or a service robot, (3) a transport machine such as a conveyor, and (4) a vehicle. The actuator 10 is an integral actuator in which a motor casing 24 and a speed reducer casing 34 (described below) are integrated with each other. The actuator 10 includes a motor 14 having a motor main body 12, and a speed reducer 16 that decelerates the rotation that is output from the motor main body 12. In addition, the actuator 10 includes a counter load-side casing 18 that is disposed on a counter load side with respect to the motor casing 24 of the motor 14, and a circuit board 20 that is fixed to the counter load-side casing 18, as an arbitrary configuration. Hereinafter, a direction along a rotation center line L22 of a motor shaft 22 of the motor 14 will be simply referred to as an axial direction, and a radius direction and a circumferential direction of a circle centered on the rotation center line L22 will be simply referred to as a radial direction and a circumferential direction. In addition, a side (a left side on a paper surface of FIG. 1) toward the speed reducer 16 from the motor 14 in the axial direction will be referred to as a load side, and a side opposite thereto (a right side on the paper surface of FIG. 1) in the axial direction will be referred to as a counter load side. The motor 14 includes, in addition to the motor