JPH0565317B2 - - Google Patents

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) Conventionally, a rotating first arm has a second arm that rotates about an axis parallel to the rotation axis of the first arm at the tip thereof, and a power tool is provided at the tip of the second arm.
JP-A 57/1999 discloses an apparatus in which the first arm can be rotated more than 360 degrees to expand the working range when the first arm and the second arm are rotated appropriately to position the above-mentioned work tool on a plane. -No. 173487 and Utility Model Kai 59-
The one shown in No. 160182 has been proposed.

In these devices, the rotation drive sources of the two arms are placed on the fixed side, so that the first arm does not interfere with other objects, and the cables of the rotation drive sources do not get tangled or twisted. One of its features is that it can be rotated without any movement, allowing its working range to be over 360°.

However, since both have a working tool installed at the end of the second arm, an air tube or cable is required to connect the working tool and the control unit installed on the fixed part in order to supply compressed air and power to the working tool, and to send and receive signals. etc. are essential.

When considering the installation of tubes, cables, etc., if the first arm rotates 360 degrees or more, the tubes, cables, etc. will be twisted or bent.
Due to the risk of wire breakage and damage, it was practically impossible to extend the rotation range of the first arm to 360 degrees or more.

The above-mentioned problem also occurs when an actuator is provided on a rotating part such as an arm in order to rotate the work tool around an axis parallel to the first arm rotation axis.

Furthermore, since the second arm is driven by a link, the rotation range of the second arm must be substantially 140 degrees or less. For example, when moving a power tool from point A to point B as shown in FIG. If the second arm passes under the first arm, the rotation angle of the first arm becomes θ ₁ , whereas the second arm passes under the first arm.
Since the arm cannot be moved beyond the arm line, the rotation angle of the first arm increases to θ ₂ and there is a problem that the working time becomes longer.

(Purpose) The present invention was made in view of the above-mentioned problems, and it reduces the working time by rotating the first arm and the second arm by more than 360 degrees without interfering with each other, and at the same time, there is a risk of twisting or breaking the wiring. The purpose is to prevent

(Structure) In order to achieve the above object, the present invention comprises two direct drive motors each having an annular rotor arranged between a pair of concentrically arranged stators, arranged vertically and coaxially with a predetermined gap between them. A fixed shaft is fitted into the central cavity of both direct motors, and a first arm base and a second arm driving pulley are rotatably pivoted to the fixed shaft in the gap, and the two direct motors are connected to each other. is integrally coupled to the rotor of the first
This is an articulated robot in which a driven pulley fixed to a second arm rotating shaft disposed at the tip of the arm and the second arm driving pulley are connected using a rotation transmission means, and the second arm driving pulley is connected to a fixed shaft of a fixed base. A first slip ring is attached to the rotation shaft at the tip of the first arm, a second slip ring is attached to the tool shaft at the tip of the second arm, and a third slip ring is attached to the tool shaft at the tip of the second arm.
A slip ring was provided, and the wiring inside the fixed shaft was connected to the second slip ring through the first slip ring, then through the rotating shaft at the tip of the first arm to the third slip ring, and then through the tool shaft to the hand. It is characterized by this. 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 cylinder 7 connected to the upper part of the fixed pedestal 1 via a coupling ring 6. It is connected to a ball screw 9 that is pivotally supported. Reference numeral 10 denotes a linear bearing provided on a cylindrical base 11, which engages with a linear guide 12 provided on the support tube 7. The base 11 is fixed at its upper end to a flange 13a formed at the lower end of the fixed shaft 13. Further, a nut 15 screwed onto the ball screw 9 is fixed to the lower end of the support base 14 attached to the flange 13a.

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

In the direct drive motor 16, an annular rotor 16d between a pair of concentrically arranged stators 16b and 16c is supported by bearings 16e and 16f, and the rotor 16d is connected to the stator 16.
It is configured to protrude from the upper ends of b and 16c as an output shaft. This protrusion 16g is coupled to the base 17a of the first arm 17.

The fixed shaft 13 protrudes further from the direct motor 16, passes through a hole 17b formed in the base 17a of the first arm 17, protrudes until a gap is created above the direct drive motor 16, and the flange 18 is fixed to the upper part. There is. A hole 19 penetrating the center of the gap in the lower surface of the flange 18
A direct drive motor 19 is attached so that the fixed shaft 13 passes through the a.
In the direct drive motor 19, an annular rotor 19d between a pair of stators 19b and 19c arranged concentrically is supported by bearings 19e and 19f.
It is configured to protrude from the lower end of c as an output shaft. The output shaft 19g has a bearing 2 on the fixed shaft 13.
It is connected to a sleeve 21 which is pivotally supported by 0. A pulley 22 is pivotally supported in the middle of the sleeve 21, and connected to the output shaft of a servo motor 23 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 pulley 24 and the pulley 24, and is rotatably connected to the pulley 24.

A pulley 26 is fixed to the lower end of the sleeve 21. On the other hand, at the distal end of the first arm 17, a second arm rotation shaft 27 is supported in parallel to the fixed shaft 13 by bearings 28 and 29 fixed to the distal end 17. A hollow 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 thereto. This hollow second arm rotation shaft 27
Inside the second arm rotation shaft 27, an inner shaft 32, which is also hollow, 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 pulley 30, and a pulley 35 is fixed to this protrusion. The pulley 35
is rotatably connected to the lower part of the pulley 22 by a timing belt 36 stretched between the pulley 22 and the lower part of the pulley 22.

The second arm rotation shaft 27 is connected to the base 37a of the second arm 37 at its lower part. The other end of the inner shaft 32 protrudes from the base 37a of the second arm 37, and is connected to a pulley 38 at the protrusion. The pulley 38 includes 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, and a timing belt 43 stretched between them. Rotationally connected by. 44 is a hand fixed to the lower end of the tool shaft 41. The wiring connected to the power source is connected from the connector 50 of the fixed pedestal 1 through the inside of the base 11, through the inside of the hollow fixed shaft 13, and to the first slip ring 49 on the outer periphery of the fixed shaft 13, the drive motor 19, and the servo motor 23. A second slip ring 48 attached to the second arm and a first slip ring 49 are connected by a wiring 46. The wiring 46 connected to the second slip ring 48 passes through the guide pipe 47 in the rotation shaft 27 and passes through the tool shaft 4.
1, and is connected to the hand 44 through the inside of the tool shaft 41.

Further, the second arm 37 has a length such that it does not engage with the base 11 when rotated, as shown in FIG.

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, direct drive motor 1
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.

Furthermore, the first arm 17, the second arm 37, and the hand 44 are arranged so as not to 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 the hand is connected to a fixed axis. 13 to the fixed side, and the wiring to the hand is also connected to the fixed side via three slip rings.
Wiring will not twist or break even when rotated more than 360°.

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

(Effects) The present invention comprises two direct drive motors each having an annular rotor arranged between a pair of concentrically arranged stators, which are arranged vertically coaxially with a predetermined gap between both direct drive motors. A fixed shaft is fitted into the central cavity, and 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. The articulated robot is an articulated robot in which 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, the robot having a fixed base. A first slip ring is installed on the fixed shaft, a second slip ring is installed on the rotating shaft at the end of the first arm, and a third slip ring is installed on the tool shaft at the end of the second arm.The wiring inside the fixed shaft is connected to the first slip ring. It is connected to the second slip ring through the shaft, then to the third slip ring through the rotation shaft at the tip of the first arm, and then to the hand through the tool shaft.
arm and second arm without interfering with each other.
It can rotate more than 360 degrees, reducing work time and preventing the risk of wiring twisting or breaking.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of an embodiment of the present invention, FIG. 2 is a front view of the same, and FIG. 3 is a plan view illustrating the operation of a conventional device. DESCRIPTION OF SYMBOLS 1... Fixed pedestal, 13... Fixed shaft, 16, 19... Direct drive motor, 16a, 19a... Center cavity, 16b, 16c, 19b, 19c... Stator, 16d, 19d... Rotor, 17... First arm, 27... Second arm rotation axis, 37...second
Arm, 44... Tool shaft, 45... Third slip ring, 46... Wiring, 48... Second slip ring,
49...First slip ring.

Claims (1)

[Claims] 1 Two direct drive motors with an annular rotor arranged between a pair of concentrically arranged stators are arranged vertically and coaxially with a predetermined gap, and fixed in the central cavity of both direct motors. A first arm base and a second arm driving pulley are rotatably connected to the fixed shaft in the gap, and each is integrally connected to the rotor of two direct motors, and the first arm The second one located at the tip
A driven pulley fixed to the arm rotation shaft and the second
It is an articulated robot in which arm driving pulleys are connected using a rotation transmission means, and includes a first slip ring on a fixed shaft of a fixed base, a second slip ring on a rotating shaft at the tip of the first arm, and a second slip ring on a rotating shaft at the tip of the first arm. A third slip ring is provided on the tool shaft at the tip of the second arm, and the wiring inside the fixed shaft is routed through the first slip ring to the second slip ring, and further through the rotating shaft at the tip of the first arm to the third slip ring. Furthermore, this is a rotating device for an articulated robot that uses a direct drive motor that is connected to the hand through the tool shaft.