JPS62188687A - 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 Field of Industrial Application The present invention relates to a horizontal articulated industrial robot whose arm is directly driven by a prime mover without the use of a speed reducer, and which transfers and assembles work objects on a flat surface. It is.

Conventional technology Conventionally, robots for flat work that mainly move horizontally were
Most of the robots are horizontal articulated robots with serial arms, so-called scalar robots, the specific configuration of which is shown in the figure.

This includes a first arm 3 that is rotatably coupled to a support column 2 that is integrated with a base 1, a first motor 4 that drives this arm, and a first reduction gear that is generally represented by a harmonic reduction gear. The other end of the first arm 3 has a second arm 6 rotatably coupled to it, a second motor 7 and a second reduction gear for driving this, and the other end of the second arm 6 has a It is equipped with a rotation means that is interlocked with an actuator 9 for vertical movement (generally a small motor equipped with a deceleration means such as an air cylinder or a pole screw) and a motor actuator 10 attached to the support column 2 and is transmitted by a timing belt 11 or the like. .

Problems to be Solved by the Invention However, in the above configuration, since the arms are connected in series, the first arm 3 and the second arm 6 interfere with each other during robot operation, and the first drive motor 4 and the second motor 7 as a disturbance, resulting in deterioration of controllability. Further, since the second motor 7 and the vertical movement motor 9 are installed on the arm, the self-inertial force of the arm increases and the driving torque increases. As a result, a large motor is required and disturbances further increase, leading to deterioration of controllability.

The present invention was invented in view of the above problems, and provides a high-speed, high-precision, direct-drive industrial robot by reducing interference torque between arms and inertia torque of the arms, and improving controllability. It is something.

Means for Solving the Problems In order to solve the above problems, the industrial robot of the present invention includes a first prime mover that is fixedly installed on a base, and a first prime mover that is directly fixed to the output shaft of the first prime mover. a second arm rotatably coupled at the other end of the first arm;
a third arm rotatably coupled at the other end of the second arm; a fourth arm having a rotation axis in the middle of the third arm and having a rotation axis common to the rotation axis of the third arm; , a second prime mover fixedly installed on the base and having the fourth arm directly fixed to the output shaft, and a hand section provided at the other end of the third arm and having a vertical movement mechanism and a rotation mechanism. , a third prime mover and a fourth prime mover for driving the vertical movement mechanism and rotation mechanism of the hand section are installed on the base.

Function The present invention, as configured above, includes a first prime mover, a second prime mover,
By installing the third prime mover and the fourth prime mover on the base, the self-inertia of the arm can be reduced. Also, by making the arms into a closed loop, the arm length of each arm (first .
Second. Third. 4th arm each 61-12m13-14
shall be. ), arm mass (mass of the 1st, 2nd, 3rd, and 4th arms in ml.

m29m39m4. ) and center of gravity position (1st, 2nd
, 3rd. The positions of the centers of gravity of each of the fourth arms and the distances from each connection point are hl, h2. h3゜h4
shall be. ) ° can be installed so as to satisfy the condition m211h2=m312h3, and the effect of reducing the mutual interference torque generated between the first arm and the fourth arm occurs, which is compatible with the above-mentioned reduction in the self-inertia of each arm. As a result, the drive torque of the prime mover and the interference torque that causes disturbance to the control system are reduced, and controllability can be improved.

Note that by aligning the axes of the first to fourth prime movers, the rotation range of each arm is expanded.

EXAMPLE An industrial robot according to an example of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view showing the configuration of an embodiment of the present invention.

In FIG. 1, 12 is a base plate part 12b, a bracket part 12
aφ), 13 is a first prime mover fixedly installed on the bracket portion 12a of the base 12, and a fourth prime mover 14 is fixed to the base 12 sharing the same axis.

16 is the output shaft of the first prime mover 13;
6, a first arm 17 is directly fixedly coupled to the second arm 17, and a second arm 17 is rotatably coupled to the other end of the first arm 16;
8 is a third arm rotatably coupled to the other end of the second arm 17;
Arm 19 is a fourth arm that has a rotation axis 60 in the middle of the third arm 18 and has a rotation axis common to this rotation axis 5o. A second motor 21 is held on the base 12m portion 12b and installed so that its axis coincides with the first motor 13.
A prime mover 22 is a third prime mover that shares the same axis as the second prime mover 21 . 23 is an output shaft of the second prime mover and is directly coupled to the fourth arm 19.

Reference numeral 24 denotes a vertical drive ball screw (vertical movement mechanism) provided at the tip of the third arm 18, which is connected to the output shaft 27 of the fourth prime mover 14 through timing belts 25 and 26, and the driving force is transmitted thereto. 28 is a rotating spline shaft (rotating mechanism) provided at the tip of the third arm 18 and connected by a ball screw 24 and a bracket 29, and is connected to the output shaft 32 of the third prime mover 22 by timing belts 30 and 31 for rotation. force is transmitted. 33 is a gripping chuck provided at the tip of the spline shaft 28. 34
is the hand part that holds these. Third
FIG. 2 is a cross-sectional view showing the configuration of prime movers 21 and 22. 1st. The configuration of the fourth prime mover is also similar to that shown in FIG.

36 is a stator of the second prime mover 21; 36 is a rotor integrally engaged with the output shaft 23; 37, 38;

39 is a bearing that rotatably supports this rotor. 4
0 is an encoder that detects the rotational position of the second prime mover. Reference numeral 41 denotes a housing portion of the second prime mover, which is fixedly and integrally engaged with the base 12.

42 is a stator of the third prime mover, 43 is a rotor integrally engaged with the output shaft 32, and 44 is a rotor 43 connected to a bearing 37.
．． This is a bearing that rotatably supports 3B. Jealousy is the third
This is an encoder that detects the rotational position of the prime mover.

Reference numeral 46 denotes a housing portion of the third prime mover 22, which is integrally connected to the housing 41 via an intermediate housing 47, and is connected to the base 12.
It is fixedly connected to.

The operation of the industrial robot configured as described above will be explained.

In general, industrial robots that mainly perform work on a flat surface are required to move to arbitrary positions on a flat surface. The robot of the present invention operates the first arm 16 and the 47th arm 19 by operating the first prime mover 13 and the second prime mover 21.
moves by a predetermined angle, and the hand portion 34 installed at the tip of the third arm 18 is moved by a closed loop link mechanism formed by the second and third arms 17 and 18 rotatably engaged with these arms. Move into position.

Next, positioning by vertical and rotational movement of the tip hand portion 34 will be explained. For vertical movement, the fourth prime mover 14
Due to the operation of
A driving force is transmitted to the ball screw 24, and the ball screw 24 is moved to an arbitrary height. The rotational movement of the chuck 33 is achieved by rotating the spline shaft 28 via the timing belts 30 and 31 also disposed within the fourth arm 19 and the third arm 18 by the operation of the third prime mover 22 to achieve a predetermined rotation angle. Can be set. Furthermore, as described in the section on means for solving the problem, by setting the length, mass, and center of gravity of each arm to satisfy certain conditions, interference torque between the arms can be suppressed. Result tube 1. Second prime mover 13.
The disturbance ring (interference torque and nonlinear torque) exerted on the motor 21 is reduced, and the controllability of the prime mover is improved.

Effects of the Invention As described above, according to the present invention, the prime mover for positioning the arm on the plane, which performs the basic movements necessary for plane work, and the vertical and rotational movements of the hand, is fixed on the base, and the shape of the arm is adjusted. By using a closed-loop link configuration, a lightweight arm can be realized, which is extremely useful for practical use as it reduces the size of the motor and improves controllability.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of an industrial robot according to an embodiment of the present invention, FIG. 2 is a sectional view of a unit constituting a prime mover, and FIG. 3 is a configuration diagram showing a conventional example. 12...Base, 13...First prime mover, 14...Fourth prime mover, 16...First prime mover
Arm, 17...Second arm, 18...
・3rd arm, 19...4th arm, 21...
...Second prime mover, 22...Third prime mover, 2
4...Ball screw, 28...Spline shaft, 6°...Rotation axis. Name of agent: Patent attorney Toshio Nakao and 1 other person2
---Yi person 3rd - O1gb Shin 14-・Ima+ Da 1st figure Pa-917-4 f7--O2 ri No. 8---3rd-19-1-χ To 1 2 Zuichi --Tz 汽运术过时闭22・-+3 The 2dar--Hole Shift 28-°-Spline Middle Figure 2

Claims (2)

[Claims] (1) A first prime mover fixedly installed on a base, a first arm fixedly attached directly to the output shaft of the first prime mover, and a first arm rotatably coupled at the other end of the first arm. a second arm, a third arm rotatably coupled at the other end of the second arm, and a third arm having a rotation axis in the middle of the third arm and having a rotation axis common to the rotation axis. 4 arms, a second prime mover that is fixedly installed on the base, and the fourth arm is directly fixed to the output shaft, and a hand section that is provided at the other end of the third arm and has a vertical movement mechanism and a rotation mechanism. and a third mechanism for driving the vertical movement mechanism and rotation mechanism of the hand section.
An industrial robot in which a prime mover and a fourth prime mover are fixedly installed on the base. (2) The first prime mover that drives the first arm, the second prime mover that drives the fourth arm, and the third prime mover and fourth prime mover that drive the vertical movement mechanism and rotational movement mechanism in the hand part share the same axis. The industrial robot according to claim 1, wherein the industrial robot is installed on the same base.