JPS61252090A - Turning gear for joint type robot using direct drive motor - 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 (Technical Field) The present invention relates to a rotating device for an articulated robot using a direct drive motor.

(Prior Art) FIG. 3 shows a conventional articulated robot. This is pedestal 61
A body 63 is attached to a column 62 fixed to the column 62. The body 63 is formed into a flange shape at both ends, and motors 64.6 are mounted on the flange portions 63α and 63b.
5 are installed at opposite positions. motor 64.6
The output shafts of No. 5 are connected to a first arm 66 and a third arm 67, respectively, via reduction gears (not shown). A second arm 68 is pivotally supported at the tip of the first arm 66, and the middle of the second arm 68 and the third arm 67 are rotatably connected by a link 69 to form a parallelogram mechanism.

70 is a hand attached to the tip of the second arm 68.

The structure is such that the hand 70 can be positioned in a plane by appropriately controlling the rotation of the motors 65 and 64. In this structure, the motor that drives the arm is attached to the body 63, which is a fixed part, which has the advantage of reducing the weight of the arm and increasing the rotation speed of the arm. This had the disadvantage that the range of rotation of the arm was limited.

In addition, the drive motor is similarly arranged in the fixed part as shown in Fig. 6 of JP-A No. 57-173487, and the
As shown in Japanese Patent No. 9-160182, a device has been proposed in which the rotary drive shaft is a double shaft and the rotation range of the arm can be obtained by more than 360°.

However, since the devices shown in these publications have two rotating shafts, one of which is supported within the other, the shaft for rotational connection (especially the inner shaft) becomes quite long. Therefore, due to the increase in motor load inertia, the response of the motor and the acceleration of the arm are poor, and even if the motor is installed in a fixed part to reduce the weight of the moving part, the arm speed will not increase as much as expected. Not only is it impossible to do this, but the long shaft causes torsion, which causes vibrations and other problems that adversely affect the positioning accuracy of the arm.

(Objective) The present invention has been made in view of the above-mentioned problems, and it aims to reduce the load inertia of the drive shaft, improve motor response and acceleration, increase arm speed, and increase positioning accuracy. Another object of the present invention is to provide a rotation device for an articulated robot that can make the rotation range of an arm more than 360 degrees.

(Structure) In order to achieve the above object, the present invention includes two direct motors each having an annular rotor arranged between a pair of concentrically arranged stators, arranged vertically coaxially with a predetermined gap between them, A fixed shaft is fitted into the center hollow part of both direct motors, and a first arm base and a second arm driving pulley are rotatably connected to the fixed shaft in the gap, and the rotors of the two direct motors are connected to each other. A driven pulley fixed to a second arm rotation shaft disposed at the tip of the first arm and the second arm driving pulley are connected using a rotation transmission means. be. Hereinafter, a detailed explanation will be given based on an example.

A servo motor 4 equipped with an encoder 2 and a brake 3 is installed on a fixed pedestal 1, and a shaft 5 of the servo motor 4 is connected to a bearing 8 provided in a support tube 7 connected to the upper part of the fixed pedestal 1 via a coupling 6. It is connected to a ball screw 9 that is pivotally supported. 10 is a linear bearing provided on a cylindrical base 11, and a linear guide 1 provided on the support tube 7.
It is engaged with 2. The base 11 is fixed at its upper end to a seven flange 13α formed at the lower end of the fixed shaft 13. In addition, the support stand 14 attached to the 7 flange 13α
A nut 15 screwed onto the ball screw 9 is fixed to the lower end of the holder.

A direct drive motor 16 is fixed to the upper end of the seven flange 13α, and a fixed shaft 13 connected to the flange 13α is fitted into a central cavity 16α of the direct drive motor 16.

The direct drive motor 16 has an annular rotor 16d between a pair of concentrically arranged stators 165 and 160, which is supported by bearings 16e and 16f, so that the rotor 16d protrudes from the upper ends of the stators 16b and 16C as an output shaft. It is configured. This protrusion 16
! I is coupled to the base 17cL of the first arm 17.

The central cavity 19α of the direct drive motor 19 is fitted into the upper part of the fixed shaft 13, and the direct drive motor 19 is inserted into the 7 flange 18 at the upper end of the fixed shaft 13 so that a predetermined gap exists between both direct drive motors 16 and 19. It is fixed at Direct drive motor 19
is a pair of stators 19b arranged in a concentric ring shape.

The annular rotor 19d between the bearings 19g and 19f
The rotor 1'M is supported by the stators 19b and 19.
It is configured to protrude from the lower end of C as an output shaft. The output shaft 19.7 is connected to a sleeve 21 which is supported by a bearing 20 on the fixed shaft 13. The sleeve 2
A drive pulley 22 is pivotally supported in the middle of the drive pulley 22, and the pulley is connected to the output shaft of a servo motor 23, which is connected to the upper part of the pulley and the flange 18 so that its output shaft is parallel to the direct drive motor 19. A timing belt 25 is stretched between the timing belt 24 and the timing belt 24, and is rotatably connected to the timing belt 25.

A pulley 26 is fixed to the lower end of the sleeve 21. - At the tip of the force cylinder 1 arm 17, a hollow second arm rotation shaft 27 is supported in parallel to the fixed shaft 13 by bearings 28 and 29 fixed to the tip 17. A hollow driven pulley 30 is fixed to the upper end of the second arm rotation shaft 27, and a timing belt 31 is stretched between the pulley 26 and the pulley 26, and the pulley 30 is rotatably connected to the pulley 30. Inside this hollow second arm rotation shaft, a hollow inner shaft 32 is supported by bearings 33 and 34 provided on the inner diameter of the second arm rotation shaft 27. One end of the inner shaft 32 protrudes beyond the driven pulley 30, and a pulley 35 is fixed to this protrusion. The pulley 35 is rotationally connected to the lower part of the pulley 22 by a timing belt 36 stretched between the pulley 35 and the lower part of the pulley 22.

The second arm rotation shaft 27 has a second arm 37 at its lower part.
It is connected to the base 37a of. The other end of the inner shaft 32 protrudes from the base 37α of the second arm 37, and is connected to a pulley 38 at the protrusion. The pulley 38 is rotated by a timing belt 43 stretched between a pulley 42 fixed to a tool shaft 41 which is supported at the tip of the second arm 37 by bearings 39 and 40 in parallel with the second arm rotation shaft 27. connected.

44 is a hand fixed to the lower end of the tool shaft 41.

In addition, 45 is a first bolt for applying pressure so that the wiring 46 to the hand does not get tangled or break when the tool shaft 41 rotates.
The wiring 46 is connected to the hand through the inner diameter of the hollow tool shaft 41.

Further, this wiring passes through a guide pipe 47 formed in the hollow of the inner shaft 32 and passes through a second slip ring 48 provided at the top of the tip of the first arm 17 so as to be coaxial with the inner sleeve. is connected to. Second slip ring 4
8, the M46 is connected to the third slip ring 49 provided on the outer periphery of the direct drive motor 16 through the inside of the first arm 17, and then connected to the connector provided on the fixed pedestal 1 through the inside of the base 11. I am led by 50. On the other hand, the fixed shaft 13 is formed in a hollow shape, and the wiring 51 of the direct drive motor 19 and the servo motor 23 is led to the connector 50 through the inside of the base 11 through its inner diameter.

Further, when the second arm 37 rotates around the rotation axis of the second arm as shown in FIG.
The length is such that it does not interfere with 6 or the base 11.

Next, the effect will be explained.

When the servo motor 4 is rotated, the base 11 moves up and down together with the arm. Since the servo motor 4 is equipped with a brake 3, it can be prevented from falling during a power outage. Also, when the direct drive motor 16 is rotated, the first arm 17 is activated, when the direct drive motor 19 is rotated, the second arm 37 is activated by the timing belt 31, and when the servo motor 23 is rotated, the timing belt 25,
Since the tool shaft 41 can be rotated by the tools 36 and 43, the positioning of the hand 44 in space and the rotational posture of the hand around the axis can be controlled by the above.

In addition, the first arm 17, second arm 37, and hand 44 are arranged so that they do not interfere with each other so that each can rotate more than 360 degrees, and the wiring of the motor that drives the second arm and/or hand is fixed. The wiring passes through the inside of the shaft 13 and is led to the fixed side, and the wiring to the node 1 is also connected to the fixed side via three slip rings, so the arm and hand can rotate more than 360 degrees on the wiring. Even if the wiring is twisted or broken, it will not occur.

Incidentally, the above-mentioned timing belt can be replaced by various rotation transmission means such as links, wires, chains, etc.

(Effect) The present invention comprises two direct motors each having an annular rotor arranged between a pair of concentrically arranged stators, which are arranged vertically and coaxially with a predetermined gap between them. a fixed shaft is fitted into the gap, a first arm base and a second arm driving pulley are rotatably pivoted to the fixed shaft in the gap, and each is integrally connected to the rotor of the two direct motors; Since the driven pulley fixed to the second arm rotation shaft disposed at the tip of the first arm and the second arm driving pulley are connected using a rotation transmission means, the load inertia of the drive shaft can be reduced. It is possible to improve the responsiveness and acceleration of the motor, increase the speed of the arm, increase the positioning accuracy, and increase the rotation range of the arm to 36σ or more.

[Brief explanation of drawings]

FIG. 1 is a front sectional view of an embodiment of the present invention, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a front view of a conventional device. 1...Fixed pedestal 13...Fixed shafts 16, 19
...Direct drive motor 16α, 19α...
・Central cavity 16b, 16C, 19b, 19cm2 cheetah 15c!
, 19d... Rotor 17... First arm 26.
...Drive pulley 27...Second arm rotation shaft 30.
... Driven pulley 31 ... Timing belt 37 ...
...Second arm patent applicant Pentel Co., Ltd. Figure 2 Figure 3 Procedural amendment (voluntarily submitted) July 15, 1985 Michibu Uga, Commissioner of the Patent Office 1, Indication of the case 1985 Patent application No. 93358 2, Name of the invention Rotation device for articulated robot using direct drive motor 3, Relationship to the case of the person making the correction Patent applicant address 7-2 Kokinumachi, Nihonbashi, Chuo-ku, Tokyo Name (
551) Pentel Co., Ltd. 4, Agent address: 2-2-5-5 Shinbashi, Minato-ku, Tokyo, Date of amendment order: 6, Subject of amendment: Drawing 2

Claims (1)

[Claims] Two direct motors with an annular rotor arranged between a pair of concentrically arranged stators are arranged coaxially above and below with a predetermined gap, and a fixed shaft is fitted into the central cavity of both direct motors. A first arm base and a second arm driving pulley are rotatably pivoted to the fixed shaft in the gap, and each is integrally connected to the rotor of two direct motors, and is disposed at the tip of the first arm. A rotating device for an articulated robot that uses a direct drive motor that connects a driven pulley fixed to a second arm rotating shaft and a pulley for driving the second arm using a rotation transmission means.