WO1993017837A1

WO1993017837A1 - Articulated robot

Info

Publication number: WO1993017837A1
Application number: PCT/JP1993/000281
Authority: WO
Inventors: Hiroaki Takechi; Tatsunori Suwa; Takashi Ono
Original assignee: Kabushiki Kaisha Komatsu Seisakusho
Priority date: 1992-03-06
Filing date: 1993-03-05
Publication date: 1993-09-16
Also published as: JPH068182A

Abstract

An articulated robot, wherein a small circle, small square and the like can be cut with high precision without the motion of a main body of an articulated robot (2), and moreover, an operating space can be enlarged for cutting a large circle, large square and the like. To ensure such operations, the proximal end portion of a first arm (6) is rotatably supported on a support member (5) fixed to the forward end portion (1) of the articulated robot (2), the proximal end portion of a second arm (7) rotatable in a horizontal plane is supported on the other (forward) end portion of the first arm (6) to thereby form a seven- or eight-axial robot, and a tool gripping member (13) is provided at the forward end portion of the second arm (7).

Description

Description Multi-entry bot

Technical field

The present invention relates to an industrial articulated robot having a new shaft configuration. Background technology

Conventional industrial articulated robots do not have a configuration in which the gripper itself moves when the gripper that supports the processing tool needs to be moved, and it is close to the robot body or the robot body. The grip was moved by moving the arm. Therefore, there is a problem that a large horsepower is required when the gripper is moved at a high speed, and the positional accuracy is low. On the other hand, for example, Japanese Patent Application Laid-Open No. 63-25050 and Japanese Utility Model Application Laid-Open No. 9-23992 have been proposed, and a considerable part of the above-mentioned problems can be solved.

However, according to the techniques disclosed in the above publications, the trajectory that can be cut and cut is smaller than the outermost diameter of the gripping device of the processing tool, and the operating range is narrow for the size of the gripping device. In addition, when such a gripping device is attached to the tip of an articulated robot to cut a work, there is a new problem that the gripping device interferes with the work and becomes an obstacle. Disclosure of Kishimei

The present invention does not operate each axis of the conventional 5- or 6-axis robot, but uses a small circle or square formed by the trajectory of two arms that roll on a horizontal plane provided at the end of the robot. Providing a multi-joint robot with a new shaft configuration that can cut at high speed and high precision, and when cutting with a 5- or 6-axis robot, both arms are tapped and the posture can be changed so as not to interfere with the workpiece It is intended to do so. For this reason, the present invention provides a support member fixed to the distal end of a multi-joint robot main body having five or six axes, which supports the base end of the first arm so as to be able to roll around, and the other first arm. A 7- or 8-axis robot is configured by supporting the base end of the second arm that rolls in the same plane at the tip of the arm, and a tool gripping member is provided at the other end of the second arm. .

When cutting a small diameter circle or square, the position is determined by the 5- or 6-axis robot body, and the first arm is turned by the first drive motor. When the second drive motor is driven, the second arm is turned with respect to the first arm, thereby drawing an arbitrary trajectory in a plane where the tool gripping member fixed to the distal end side of the second arm extends. Driven. By attaching a plasma cutting torch or a YAG laser torch to this tool gripping member, the work is cut along the above-mentioned trajectory.

Also, when cutting with the 5- or 6-axis mouth-botting body as in the conventional mouth-botting, both arms are turned by the first drive motor and the second drive motor, and the posture is set so as not to interfere with the work. Cut any trajectory while changing or after changing.In addition, if you want to cut a wide range of straight lines or curves and add small roundness to the corners, first use a straight line or -5 with the S-axis robot body. The curve is cut, and then the small roundness is cut with high precision using the combination of the movements of the first arm and the second arm. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a side view of an industrial multi-articulated robot according to the present invention, FIG. 2 is a plan view showing a main part of the first embodiment of the present invention, and FIG. 3 is a main view of the first embodiment of the present invention. FIG. 5 is a cross-sectional view showing a second embodiment of the present invention, FIG. 5 is a cross-sectional view taken along the arrow A in FIG. 4, FIG. 6 is a cross-sectional view taken along line BB of FIG. 4, and FIG. FIG. 8 is a plan view showing an essential part of the second embodiment of the invention, FIG. 8 is an explanatory view of an operation in the first embodiment shown in FIG. 2, FIG. 9 is a flowchart showing an operation of cutting a figure by a plasma cutting torch, FIG. 0 is arbitrary with plasma torch 5 is a flowchart showing an operation when cutting a shape. BEST MODE FOR CARRYING OUT THE INVENTION

The configuration of the first embodiment of the present invention will be described with reference to FIGS.

In FIGS. 1 and 2, reference numeral 1 denotes a distal end of a six-axis articulated robot 2, and reference numeral 3 denotes two surface-turning first arms 6 attached to the distal end portion 1 of the mouth robot 1 via a bracket 4. And a tool holding device having a second arm 7. A support member 5 is fixed to the bracket 4, and the base end of the first arm 6 is rotatably supported by the support member 5. The distal end portion of the first arm 6 of the other, and _c proximal end of the second arm 7 is rotatably supported, the support member 5 and the second arm 7, the first driving motor 8, respectively The second drive motor 9 is fixed.

The output shaft 8a of the first drive motor 8 is connected to a shaft 6a formed at the base end of the first arm 6 via a first reduction gear 10, as shown in FIG. Further, the output shaft 9 a of the second drive motor 9 is connected to a shaft 6 b formed at the tip of the first arm 6 via the second reduction gear 11. The first and second reduction gears 10 and 11 use wave gears (product name: Harmonic Drive), which are compact in configuration and light in weight. Also, a tool gripping member 13 is fixed to the tip of the second arm 7.

Next, a configuration of a second embodiment of the present invention will be described with reference to FIGS. However, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In FIGS. 4 and 7, the first arm 6 is driven via a first reduction gear 10 by a first drive motor 8 fixed to a support member 5. The second arm 7 is driven by a second drive motor 9 ′ fixed to the support member 5, as shown in FIGS. 5 and 6, a second reduction gear 11 ′ composed of belts 15 and 16, etc. It is performed by driving through the.

Next, the operation of the configuration of the first embodiment or the second embodiment will be described. Function 1: When cutting a small diameter circle or square, first position the body with the 6-axis robot 2 and drive the first drive motor 8 to support the support member 5. L, the first arm 6 turns. Further, by driving the second drive motor 9 or 9 ′, the second arm 7 is turned around the tip of the first arm 6, and thereby the tool fixed to the tip of the second arm 7. The axis of gripping member 13 is, for example, With, an arbitrary trajectory can be drawn in the area indicated by the diagonal lines. At this time, the workpiece is cut along the trajectory by holding the plasma cutting or YAG laser torch 12 on the tool holding member 13.

Function 2: When cutting with the main body of the 6-axis robot 2 in the same way as the conventional robot, the # 1 arm 6 and the second arm 7 are moved to change the posture so that they do not interfere with the work. By controlling the respective axes of the 6-axis robot 2 while keeping the positions of the tool holding member 13 and the support member 5 constant without moving the drive motor 8 and the second drive motor 9 or 9 ′, Cut any shape. In this case, if the first arm 6 and the second arm end do not interfere with the workpiece, it is not necessary to change their postures while cutting with the main body of the 6-robot 2.

However, in FIG. 2, when the tip 1 of the 6-axis robot 2 is moved in the direction of arrow A and the tip of the second arm 移動 is also moved in the direction of arrow B in parallel with this, When there is an obstacle 14 in the hand, the base end of the second arm 7 interferes with the obstacle 14. -So the second arm? The torch 12 gripped by the tip of the torch cannot move close to the obstacle 14, and a dead space is generated in a processing range such as cutting. In such a case, as shown in FIG. 8, the first arm 6 and the second arm Ί are turned in the opposite direction, and the leading end of the second arm 7 is directed to the obstacle 14 side. By doing so, the default space can be eliminated.

Function 3: When cutting a wide range of straight lines or curves and adding small roundness to the corners, first cut the straight lines or curves with the body of the 6-axis robot 2, and then cut the first arm 6 and the second arm. Cutting the small roundness with high precision by combining the rotational movements of the two arms 7 When cutting a small R or square on the plane の of the operation 1, the first and second drive motors 8 and 9 Or 9 'is controlled by a control device (not shown). It is also possible to cut by teaching the control trajectory based on a predetermined calculation formula. The flow chart at this time is shown in FIG. 9 and is implemented by the steps (1) to (10). As teaching, the length of the first arm 6 is 1, the length of the second arm 7 is 1 ₂ , and the angle of the first arm 6 from the reference coordinates! , The angle from the reference coordinates of the second arm 7 is _z, and the coordinate of the center point of the figure to be cut is X. In step (3), the tip of the second arm 7 is moved to the teaching point (Χο, Υο). In step (5), the coordinates of the cutting trajectory are converted into the surface tiling angle of the motor 8, 9 or 9 'of each axis. The conversion into the surface turning angle is performed by the following equation.

_{X (1, + 1 2 COS} Θ z) + Y 1 2 Sin Θ

COS

^{. 1 2 - 1 2 1,} l z COS ^ 2

! X one Y 1 ι ^ζ -1

θ COS

2 1, 1

Also, when cutting with the main body of the 6-axis robot 2 in the same way as the conventional mouth robot of function 2, the posture is changed so that the first arm 6 and the second arm 7 are moved so as not to interfere with the stroke. By controlling each axis of the 6-axis robot 2 while cutting, any shape can be cut. The feature at this time is shown in FIG. 10 and is implemented by the steps (21) to (27). INDUSTRIAL APPLICABILITY The present invention is capable of cutting a plurality of small Rs and squares with high accuracy without moving the articulated robot main body such as a six-axis robot, and is capable of cutting a plurality of small Rs and squares even when approaching a workpiece. This is useful as an industrial articulated robot that can avoid interference.

Claims

The scope of the claims

The support member fixed to the distal end of the multi-joint robot body having 1.5 or 6 axes supports the base end of the first arm so that it can turn freely, and the other end of the first arm has a horizontal plane. A multi-joint robot characterized by comprising a 7- or 8-axis robot by supporting the base end of a rotating second arm and a tool gripping member at the other end of the second arm. .

2. The first arm is driven via a speed reducer by a first drive motor attached to a support member fixed to the distal end of the multi-joint robot main body, and the second arm is driven. 2. The multi-joint robot according to claim 1, wherein the control is performed via a speed reducer by a second drive motor fixed to a distal end of the first arm.

3. The first drive motor and the speed reducer thereof are arranged at an axis symmetric position at the center of the first arm with respect to the second drive motor and the speed reducer thereof. The articulated robot described in 1.

4. The first arm is driven via a first reduction gear by a first drive motor attached to a support member fixed to the tip of the articulated robot wooden body, and the second arm is driven. 2. The multi-joint roller hood according to claim 1, wherein the driving is performed by a second drive motor attached to the support member via a second reduction gear.

5. The tool to be attached to the tool gripping member is a plasma torch or a YAG laser torch, which has a sensor to measure the distance between the tool tip and the workpiece before cutting the workpiece. The teaching point of the robot is corrected by measuring the amount of deformation of the robot, and the gap between the tool tip and the workpiece is kept constant while the workpiece is being cut. The multi-lane entrance according to claim 1, wherein the position of the tool tip is moved.