JPS62251090A - 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 [Object of the Invention] (Industrial Application Field) The present invention relates to an industrial robot, and particularly to a horizontal articulated robot.

(Prior Art) In horizontal articulated robots widely used for assembly work, each axis is conventionally configured with a combination of an electric motor and a reduction gear such as a harmonic. However, this speed reducer has poor efficiency, weak mechanical strength, and low rigidity and play, which causes vibration and reduces accuracy. On the other hand, the recently developed direct drive system, which uses a low-speed, high-torque motor to directly drive the arm, is attracting attention because it does not have the drawbacks of a reducer and allows for efficient and highly accurate positioning.

Figure 4 shows an example of this squash-shaped robot.

The first arm 2 swings with respect to the column 1, and this 17th-
There are a 27th arm 3 that swings at the tip of the second arm 2, a hand shaft 4 that rotates at the tip of the second arm 3, and two shafts 5 that move this up and down.

(Problems to be Solved by the Invention) In the conventional system configured as described above, a heavy low-speed high-torque motor must be placed on the second arm 3 or the hand shaft 4, which increases the moment of inertia. Moreover, since the wiring and piping are done all the way to the hands, the range of motion is limited. In addition, since the Z-axis 5 that realizes vertical movement is provided at the hand, the hand becomes complicated and cannot be used in places where height is restricted, such as when loading and unloading a press. Furthermore, the Z type, which consists of a linear mechanism with sliding motion near the hand, can also be applied to dust-free rooms.
This is not possible because the axis is provided.

The present invention provides an industrial robot that does not increase the moment of inertia even when using a heavy low-speed high-torque motor, has compact hands, is easy to seal when applied to a dust-free room, and has a wide range of motion. With the goal.

[Structure of the invention]

(Means for solving the problem) In FIGS. 1 and 2, a hollow low-speed high-torque motor 6.7 and a parallelogram link 8.9 are arranged on the same axis.
10.11 A ball spline 14.15 of a multi-layer structure that moves up and down by a pole screw 13 driven by a motor 12 and a ball spline bearing 16.17 are provided between the arms configured in 10.11, and a parallelogram link 8.9 is provided. .10.1
1, two adjacent sides 8 and 9 are each connected to a ball spline 14.
．． It was fixed at 15.

(Function) By driving the low speed high torque motor 6.7, the parallelogram link 8.9.10.11 changes its attitude and the tool shaft 36 at the tip moves two-dimensionally to an arbitrary position. By further driving the motor 12, the parallelogram link 8.
9.10.11 moves up and down without changing its two-dimensional posture.

(Example) Hereinafter, one example of the present invention will be described based on the drawings. In FIGS. 1 and 2, the low speed high torque motor 6 is fixed to the upper surface of the base 18, and the low speed high torque motor 7 is coaxially fixed via a spacer 19. The motor 12 is attached to a mounting seat 20 at the bottom of the base 18 and connected via a coupling 21 to a pole screw 13 rotatably supported on the mounting seat 20 by a bearing 22.

Next, ball spline bearings 16.17 are fixed to the output shafts 6a and 7a of the low-speed high-torque motor 6.7 through housings 23.24, respectively, and each supports a hollow ball spline 14.15 at its lower end. are doing. The pole screw nut 13a is fixed to the lower end of the ball spline 14 via a mounting member 25. On the other hand, the upper end of the ball spline 14 is connected to the link 8 via a joint 26, and the upper end of the ball spline 15 is rotatably connected to the link 8 via a bearing 27.
At the same time, a link 9, which is adjacent to the link 8 through a joint 28 and constitutes a parallelogram link with other links, that is, links 10 and 11, is connected. A motor 29 is provided and interlocks with the tool shaft 36 at the tip of the link 11 via toothed pulleys 30, 31, 32, 33 and toothed belts 34, 35.

Next, the operation of this embodiment will be explained. Now, by appropriately operating the low-speed high-torque motor 6.7, the shape of the parallelogram link can be changed and the tool shaft 36 at the tip of the link 11 can be moved two-dimensionally.

Further, by driving the motor 12 and rotating the pole screw, the parallelogram link 8.9.10.11 as a whole moves up and down. Furthermore, when the low speed high torque motor 29 is driven, the toothed pulleys 30, 31, 32, 33 and the toothed belt 3
4, 35, the tool shaft 36 at the tip of the link 11 rotates.

=4- According to this configuration, the parallelogram links 8,9°10,1
1, only the low-speed high-torque motor 29 placed at the center of rotation of the link 8 becomes an inertial load, and there is no major influence. Moreover, since both the low-speed high-torque shafts 6 and 7 are fixed to the base 18, the driving torques do not interfere with each other. Furthermore, since there is no need to support the arm drive low-speed, high-torque motor for vertical movement of the entire arm, high-speed movement can be achieved using a small-capacity motor.

Further, since only the wiring to the low-speed high-torque motor 29 and the piping to the hand etc. are guided to the arm movable section, the range of motion is not limited.

On the other hand, as shown in FIG. 3, a low-speed, high-torque motor 29 for the tool shaft 36 is also provided on the base 18 side, so that the coaxial multiple spline shafts can have a triple structure 14, 15, 37, and a parallelogram link (not shown) is used. The old arm mechanism becomes lighter.

〔Effect of the invention〕

As explained above, according to the present invention, the arm made of a parallelogram link and the low-speed high-torque motor fixed to the base are linked by multiple spline shafts that move up and down with a pole screw. It is possible to provide an industrial robot that does not increase the moment of inertia even when using a heavy low-speed high-torque motor, has compact hands, and has only a rotating part when applied to a dust-free room, so it is easy to seal and has a wider range of motion. can.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of the main parts showing one embodiment of the industrial robot of the present invention, FIG. 2 is an overall view of the same, FIG. 3 is a longitudinal cross-sectional view of the main parts showing another embodiment, and FIG. FIG. 1 is an overall diagram showing a conventional method. 8.9, 10.11...Link 6.7.29...Low speed high torque motor 14.15.3
7...Ball spline 13.13a...Pole screw, Natsuto agent Patent attorney Nori Chika Ken Yudo Wang Hou Hirofumi

Claims (1)

[Claims] In a horizontal articulated robot driven by low-speed, high-torque motors, at least two or more low-speed, high-torque motors are fixed to the base, and ball spline bearings are each fixed to the output shafts of the motors. An industrial robot comprising a ball spline, at least one of which is driven in the axial direction by a ball screw, and a parallelogram link including two links fixed to the end of the ball spline and each independently driven.