JPS62224592A - Wrist mechanism of industrial robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wrist mechanism for driving, and particularly to a wrist mechanism for linearly moving and rotating a robot hand.

[Conventional technology]

As an example of a conventional industrial robot, a four-axis industrial robot having four operating axes is shown in FIG. This robot belongs to a cylindrical coordinate robot in terms of operation type, and is rotated by a motor 101 around an axis 102 erected on a base 100 in the rotation direction 〇).A robot arm 104 extending from the axis 102 is - The robot arm 104 can be extended and contracted in the axial direction R by the drive unit 103 including the arm, and the robot 71 is attached to the tip of the robot arm 104 via the wrist part 106.
- A hand (not shown) is attached. This wrist part 1
06, a linear motion part 110 is guided in the vertical axis Z direction by a guide rod 108 driven by a motor (not shown) fixed to the robot arm 104, and is movable in a straight line. A flange portion 114 fixed to the tip of the output shaft of the motor 112 is formed to be rotatable (rotation direction α) by another motor 112 fixed to the front surface of the motor. The robot hand is attached to the flange portion 114 of the wrist portion 106.

[Problem that the invention seeks to solve]

However, since the linear motion part of the wrist of the conventional industrial robot mentioned above incorporates a built-in motor for rotation around the vertical axis (α), a load is placed on the drive source of the linear motion part. As the weight inevitably increases, the linear motion part itself tends to become larger. For this reason, the linear motion part has poor operational responsiveness, causing delays in starting and stopping, and the linear motion part may become an obstacle when working with a robot hand in a narrow space.

Therefore, in order to solve these problems, the present invention provides a wrist mechanism for an industrial robot that is lightweight and has a small wrist surface movement section.

[Means for solving problems]

In view of the above-mentioned objects of the invention, the present invention is directed to an industry in which the robot hand is attached to the tip of a robot arm and has a robot hand mounting means to impart movement in a linear axis direction and rotation about the same linear axis to the robot hand. In the wrist mechanism of the robot, the linear movement and rotation movement sources are fixedly held in immovable positions with respect to the robot arm, and the linear movement movement sources are operated via the first belt or chain transmission mechanism. A movable elongated shaft that is pivotally connected and can be moved linearly by a feed screw mechanism, and is engaged with the elongated shaft and is rotatably operated via the rotational operation source and a second belt or chain transmission mechanism. An industrial robot-nod characterized in that a spline shaft for transmitting rotational motion to the elongated shaft is provided in the wrist part, and the robot hand mounting means is attached to an end of the elongated shaft. Provides a wrist mechanism.

[For production]

According to the above means according to the present invention, the linear movement motion source within the wrist moves the elongated shaft linearly in the axial direction together with the moving plate by the feeding mechanism via the first transmission mechanism, and the rotational motion within the wrist moves. A source is enabled to rotate the elongated shaft via a second transmission mechanism and a splined shaft. Therefore, it is possible to linearly move only the elongated shaft out of the wrist and rotate it.

〔Example〕

The following is based on the embodiments of the present invention shown in the accompanying drawings,
FIG. 2 is a partially cutaway front view taken along arrow A in FIG. 1, with the motor and belt partially omitted.

Referring to FIGS. 1 and 2, the wrist mechanism of this embodiment is fixed to the output shaft of a motor Ml fixed to a wrist part 11 fixed to a robot arm (not shown) using an appropriate bracket member. A bearing 1 is provided with a brake 13 located above the outer upper plate 12 by a horizontal lower plate 10 fixed to the wrist portion and an upper platework 2.
5, and a pulley P2 fixed to the lower end of the ball screw shaft S1, both pulleys P1. Transmission bell) Vl stretched between P2
A transmission mechanism is formed to rotationally drive the ball screw shaft S1 via the ball screw shaft S1. A nut 14 is screwed onto the ball screw shaft S1 between the upper plate 12 and the lower plate, and when the ball screw shaft S1 is rotationally driven, the nut 14 moves a movable plate 16 horizontally fixed to the ball screw shaft S1. Accordingly, it moves along the ball screw axis S1.

A sliding tube 18 is provided near the other end of the moving plate 16 with respect to the ball screw shaft S1 so as to be movable together with the moving plate 16 in the direction of the vertical axis Z, and is rotatable about the axis of the sliding tube 18. It is attached via a bearing 20 as shown in FIG. A ball spline shaft S2 supported in the longitudinal direction is concentrically inserted into the sliding tube 18 via a bearing (not shown) in a reduction gear n22 held by the upper plate 12. The ball spline shaft S2 is engaged with a spline nut 24 fixed to the upper end of the sliding tube 18, and the sliding tube 18 is rotated in the Z direction with respect to the ball spline shaft S2 via the spline nut 24. It is movable.

A pulley P3 is fixed to the upper end of the ball spline shaft S2 (above the reducer 22), and another pulley P3 is fixed to the wrist portion 11 fixed to the robot arm (not shown) using an appropriate bracket member. A rotation transmission mechanism is configured to rotate the ball spline shaft S2 via a pulley P4 fixed to the output shaft of the motor M2 and a transmission belt 2 engaged with the pulley P3.

As a result, the sliding tube 18 is rotated (rotation direction α) by joining the spline nut 24 that is engaged with the ball spline shaft S2. Further, the ball spline shaft S2 extends to the lower end of the lower plate 10, and the upper end of the sliding tube I8 can be lowered to the vicinity of the lower plate 10 together with the movable plate 16. The percutaneous tube 18
An annular hand attachment flange 26 (not fixed) is attached to the lower end of the handle.

In this embodiment, for the purpose of smoothing the sliding movement of the movable plate 16 in the Z direction, a supporting ball spline shaft S3 is further provided between the upper plate 12 and the lower plate 1O. S2
They are arranged to form a triangle. The support ball spline shaft S3 passes through the movable plate 16 and engages with a support spline nut 28 fixed to the movable plate 16. The spline nut moves along the ball spline shaft S3 in the Z direction together with the movable plate 16.
It is possible to move along the

In this example, each axis is arranged vertically and each plate is arranged horizontally, but there is no need to limit it to this example. The present invention can also be applied to a configuration in which the

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, the motor constituting the drive source is fixedly arranged with respect to the robot arm, and the motor that constitutes the drive source is fixedly arranged with respect to the robot arm, and the motor that constitutes the drive source is fixedly arranged with respect to the robot arm, and the motor that constitutes the drive source is fixedly arranged with respect to the robot arm, and the motor that constitutes the drive source is fixedly arranged with respect to the robot arm. Since we have cleverly formed a lightweight and small wrist-related moving part, we have created an industrial robot that has good operational responsiveness, no delay in starting and stopping, and has good workability with the robot hand in narrow areas. wrist mechanism.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the configuration of the main parts of the wrist mechanism of an industrial robot according to the present invention, FIG. FIG. 1 is a perspective view showing an example of an industrial suffix having a wrist portion. IO...Lower plate, 11...Wrist part,
12... Upper plate, 13... Brake, 14... Nut, 15... Bearing,
1G... moving plate, 18... moving tube,
20...bearing, 22...reducer, 2
4...Spline nut, 26...Flange,
28... Spline nut for support, 100... Base, 101... Motor, 102... Axis, 103... Drive unit, 104... Robot arm, 106...
Wrist part, 10B... Guide rod, 110...
・Linear motion part, 112...Motor, 114
...Flange part, Ml, M2...Motor, PI, P2. P3. P4...Pulley, Sl...Ball screw shaft, S2...Ball spline shaft, S3...Ball spline shaft for support, Vl, V2...
·belt. Figure 1

Claims (1)

[Scope of Claims] 1. An industrial robot that is attached to the tip of a robot arm and has a robot hand attachment means to give the robot hand movement in a linear axis direction and rotation about the same linear axis. In the wrist mechanism, a feed screw mechanism that holds both the linear motion source and the rotation motion source in a fixed position relative to the robot arm and is operated via the linear motion source and a first belt or chain transmission mechanism. an elongated shaft that is integrally movable in a straight line by being pivotally connected to a movable plate that moves linearly; and a long shaft that is engaged with the elongated shaft and is rotatably operated via the rotational operation source and a second belt or chain transmission mechanism. A wrist mechanism for an industrial robot, characterized in that a spline shaft for transmitting rotational motion to the elongated shaft is provided in a wrist box, and the robot hand mounting means is attached to an end of the elongated shaft. 2. The industrial robot according to claim 1, wherein the elongated shaft is a hollow elongated shaft, and the spline shaft is coaxially disposed inside the elongated shaft. wrist mechanism. 3. The wrist mechanism for an industrial robot as set forth in claim 1 or 2, wherein a guide shaft inserted into the movable plate is provided to stably move the movable plate and the elongated shaft in a straight line. 4. The first and second belt or chain transmission mechanisms are spaced apart from each other in the axial direction of the elongated shaft, and are connected to the two operating sources coaxially arranged in parallel on the robot arm. A wrist mechanism for an industrial robot according to any one of claims 1 to 3. 5. Claim 1, characterized in that both of the motion sources are fixedly held within the wrist box via appropriate fixing means.
The wrist mechanism of the industrial robot according to any one of Items 1 to 4.