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EP-4741110-A1 - ARTICULATED ROBOT

EP4741110A1EP 4741110 A1EP4741110 A1EP 4741110A1EP-4741110-A1

Abstract

The articulated robot 1 includes: a first joint (joint JT1) including a first support portion (support portion 23) and a first operation portion (first end 311); a first actuator (actuator 41) whose first body (body 411) is located on the opposite side of the first operation portion from the first support portion; a second joint (joint JT2) including a second support portion (second end 312) and a second operation portion (first end 321); and a second actuator (actuator 42) in which, in a direction in which a first axis (axis Ax1) or a second axis (axis Ax2) extends, a direction in which a second shaft (shaft 422) projects is opposite to a direction in which a first shaft (shaft 421) projects.

Inventors

  • TATSUTA, Norihisa
  • YAMAMOTO, MASATO
  • KAWATA, TAKUYA

Assignees

  • KAWASAKI JUKOGYO KABUSHIKI KAISHA

Dates

Publication Date
20260513
Application Date
20240802

Claims (8)

  1. An articulated robot comprising: a first joint including a first support portion and a first operation portion arranged in a direction in which a horizontal first axis extends, the first operation portion being rotatable relative to the first support portion about the first axis; a first actuator including a first body and a first shaft projecting from the first body and connected to the first joint, the first actuator being configured to drive the first joint through the first shaft, and the first body being located on an opposite side of the first operation portion from the first support portion; a second joint connected in series with the first joint and supported by the first joint, the second joint including a second support portion and a second operation portion supported by the second support portion, the second operation portion being rotatable relative to the second support portion about a second axis parallel to the first axis; and a second actuator including a second body and a second shaft projecting from the second body and connected to the second joint, the second actuator being configured to drive the second joint through the second shaft, the second shaft projecting, in a direction in which the first axis or the second axis extends, opposite to a direction in which the first shaft projects.
  2. The articulated robot of claim 1, wherein the first body is located on a first side of the first joint in the direction in which the first axis or the second axis extends, and the second body is located on a second side of the second joint opposite to the first side in the direction in which the first axis or the second axis extends.
  3. The articulated robot of claim 2, wherein the first operation portion supports the first body.
  4. The articulated robot of claim 2 or 3, wherein the second support portion supports the second body.
  5. The articulated robot of any one of claims 1 to 4, further comprising: a third joint connected in series with the first joint and the second joint and supported by the first joint, the third joint including a third support portion and a third operation portion supported by the third support portion, the third operation portion being rotatable relative to the third support portion about a third axis parallel to the first axis; and a third actuator including a third body and a third shaft projecting from the third body and connected to the third joint, the third actuator being configured to drive the third joint through the third shaft.
  6. The articulated robot of claim 5, wherein in a direction in which the first axis, the second axis, or the third axis extends, a direction in which the third shaft projects is opposite to the direction in which the first shaft projects and is the same as the direction in which the second shaft projects.
  7. The articulated robot of claim 5 or 6, further comprising: a base that is a fourth joint rotatable about a fourth axis orthogonal to the first axis; a first link coupled to the base via the first joint; a second link coupled to the first link via the second joint; a third link coupled to the second link via the third joint; a fifth joint by which the third link is rotatable about a fifth axis orthogonal to the first axis; a fourth link coupled to the third link; a sixth joint interposed between the third link and the fourth link, by which the fourth link is rotatable relative to the third link about a sixth axis parallel to the first axis; and a seventh joint by which the fourth link is rotatable about a seventh axis orthogonal to the first axis.
  8. The articulated robot of claim 7, further comprising a hand for holding an article, the hand being supported by the fourth link.

Description

TECHNICAL FIELD The present invention relates to articulated robots. BACKGROUND ART Patent Document 1 describes a conventional articulated robot. The conventional articulated robot is a seven-joint robot. The conventional articulated robot includes a first arm, a second arm, and a third arm connected in series. An actuator of the first arm swings the first arm about a horizontal axis, an actuator of the second arm swings the second arm about a horizontal axis, and an actuator of the third arm swings the third arm about a horizontal axis. The three actuators are located on the same side in a direction along the horizontal axis, with respect to the first arm and the second arm. CITATION LIST PATENT DOCUMENT PATENT DOCUMENT 1: Japanese Patent No. 5975129 SUMMARY OF THE INVENTION TECHNICAL PROBLEM In an articulated robot with joints connected in series, a particular joint supports one or more other joints, and thus the supporting strength of that particular joint is increased. For example, a typical six-axis articulated robot includes a first arm connected to a swivel section and a second arm connected to the first arm. A particular joint that connects the swivel section and the first arm has high supporting strength in order to support a second joint that connects the first arm and the second arm. In the conventional articulated robot, the joint that connects the swivel section and the first arm is desired to have higher supporting strength than a joint of a typical six-axis articulated robot. This is because the conventional articulated robot has a larger number of arms and actuators than the typical six-axis articulated robot. The joint of the conventional articulated robot includes a connection portion of the swivel section and a proximal end of the first arm supported by the connection portion. The actuator is fixed to the connection portion. Since the actuator is fixed to the connection portion, it is difficult to enlarge the connection portion to increase the supporting strength of the joint. However, in the conventional articulated robot, the supporting strength of the joint cannot be increased. SOLUTION TO THE PROBLEM The technology disclosed herein relates to an articulated robot. The articulated robot includes: a first joint including a first support portion and a first operation portion arranged in a direction in which a horizontal first axis extends, the first operation portion being rotatable relative to the first support portion about the first axis;a first actuator including a first body and a first shaft projecting from the first body and connected to the first joint, the first actuator being configured to drive the first joint through the first shaft, and the first body being located on the opposite side of the first operation portion from the first support portion;a second joint connected in series with the first joint and supported by the first joint, the second joint including a second support portion and a second operation portion supported by the second support portion, the second operation portion being rotatable relative to the second support portion about a second axis parallel to the first axis; anda second actuator including a second body and a second shaft projecting from the second body and connected to the second joint, the second actuator being configured to drive the second joint through the second shaft, the second shaft projecting, in a direction in which the first axis or the second axis extends, opposite to a direction in which the first shaft projects. ADVANTAGES OF THE INVENTION Since the first joint of the articulated robot does not directly support the first actuator, the first joint can have high supporting strength. BRIEF DESCRIPTION OF THE DRAWINGS [FIG. 1] FIG. 1 is a rear view of an articulated robot.[FIG. 2] FIG. 2 is a side view of the articulated robot.[FIG. 3] FIG. 3 is a partially sectional rear view of the articulated robot, showing first to third joints and first to third actuators in an enlarged view.[FIG. 4] FIG. 4 is a partially sectional rear view of an articulated robot according to a modification.[FIG. 5] FIG. 5 is a partially sectional rear view of an articulated robot according to a modification.[FIG. 6] FIG. 6 is a partially sectional rear view of an articulated robot according to a modification. DESCRIPTION OF EMBODIMENTS An embodiment of an articulated robot will now be described with reference to the drawings. The articulated robot described herein is merely an example. (Overall Configuration of Articulated Robot) FIG. 1 shows an articulated robot 1. FIG. 1 is a rear view of the articulated robot 1. FIG. 2 is a side view of the articulated robot 1. The articulated robot 1 is a vertical articulated robot. The articulated robot 1 is a seven-axis robot including joints JT1 to JT7. The articulated robot 1 is used, for example, in the logistics field. Specifically, the articulated robot 1 loads articles onto a truck bed or into a container, or unloads