JPH02133188A - Laser beam machining robot - Google Patents

Abstract

PURPOSE:To obtain a working robot in which a reference attitude of a converging system is constant and an assembly property and a maintenance property are satisfactory by combining plural arms having a driving part, respectively and installing the converging system in its tip, and also, providing a laser optical path by separating it from the arm. CONSTITUTION:On a frame 10 of the upper end of a column 9 provided vertically on a base 8, a first arm 13 being oscillatable is provided, and on its tip part, a second and a third arms 17, 19 are provided so as to be oscillatable through axes 15, 18. Also, in the tip part of a third arm 19, a converging system 3 of an oscillating laser light is installed. In the laser beam machining robot 1, said first arm 13 is oscillated by a driving part 11, on the turning column 9. Moreover, a second arm 17 is oscillated by a driving part 12 through a lever 14 and a rod 23. In that case, the arm 19 connected to the frame 10 by a parallelogram link consisting of a rod, an L-shaped link 16, etc., is oscillated by using the axis 18 as an axis. On the other hand, a laser light 7 passes through an optical system 6, conduction pipes P1-P4, optical joints E1-E4, a frame 19a of a third arm 19, and a hollow axis 19b, and transmitted to the converging system 3.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a laser processing robot, and particularly to laser processing in which a workpiece is processed by guiding a laser beam transmitted from a laser oscillator to the tip of an arm. About robots.

(Conventional technique VFR) Laser processing robots, which combine lasers and industrial robots to perform welding, cutting, etc., require a smaller footprint and are easier to install than the gantry-type NC processing machines commonly used for laser processing. - It is a new field of application for lasers and robots because it is easy to move and can be easily applied to line production formats. As shown in FIG.
An optical system 6 is provided above the axis of one rotation axis using an articulated laser beam transmission system 5 such as a mirror and a pipe attached to the upper arm 4.
There are many configurations in which the laser beam 7 bent downward from the wrist is guided to a condensing system 3 at the tip of the wrist 2. Also.

Some devices use a hollow arm as a transmission path for laser light.

By the way, the field of application of this laser processing robot is mainly drilling and cutting of press-formed three-dimensional shaped workpieces, welding, etc. In particular, by taking advantage of the characteristic of laser processing that can suppress thermal distortion, it is possible to perform complicated and Many are intended for high-precision workpieces.

(To be solved by the invention [1]) By the way, in drilling, cutting, and welding such three-dimensional workpieces, the wrist, nozzle, and arm tip that directly accesses the workpiece must be small.

However, in FIG. 4, the laser beam transmission system 5 is located outside the arm 4 and wrist 2, so it is large in size. On the other hand, if the hollow part of the arm is used as the transmission path for the laser beam, the wrist and the tip of the arm will be compact. The transmission mechanism is complicated, making assembly and maintenance difficult. Next, welding of thick parts is generally performed downward, but in the conventional robot 1 shown in FIG. 4, an arm 4 with a wrist 2 at the tip
The position of the robot changes depending on the access position, and is limited to accessing only from diagonally above the robot 1 side. For example, even a simple task of standing a long part on a workpiece and welding around it cannot be done without peripheral equipment such as a positioner.

Furthermore, in order to ensure the safety that laser processing equipment requires, especially to prevent radiation to the surrounding area during beam handling, it is possible to limit the depression angle of the nozzle direction of the condensing system with respect to the horizontal depending on the surrounding shielding situation. In FIG. 4, the nozzle direction angle of the condensing system 3 changes depending on the attitude of the arm 4, so it can only be calculated by a computer, and reliable and reliable measures such as hard limits and mechanical stoppers cannot be taken.

Therefore, the purpose of the present invention is to provide easy assembly and maintenance, and to provide easy cutting and maintenance.
To obtain a laser processing robot with excellent safety, which can always perform welding work from above without interfering with a workpiece, and furthermore, can mechanically limit the depression angle of the nozzle direction angle of a condensing system.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a first arm that swings about an axis perpendicular to the pivot axis at the top of a column that pivots about a vertical axis, and the first arm that swings about an axis perpendicular to the pivot axis.
At the tip of 7-11, there is a second shaft that swings around an axis parallel to the swing axis.
An arm is provided to configure an arm mechanism with 3 degrees of freedom, and the tip of the arm is equipped with an internal laser beam transmission path that allows for rotation around a longitudinal axis and swinging around an axis perpendicular to the rotation of the nozzle of the focusing system. A third arm, which has a degree of freedom, is supported so as to be able to swing freely around an axis parallel to the swing axes of the first and second arms, and a Rondo or L-shaped link is provided between the third arm and the column. A joint section that is connected by two parallel links configured, and that guides the laser from the nine-dimensional optical system to the V end of the second arm through a transmission system, which is installed above almost coinciding with the robot's rotation center, and supports the third arm. This is a laser processing robot that is guided from the center to the focusing system at the tip via the axis of the 37th arm.

(Function) As a result, the tip of the second arm is three-dimensionally positioned at an arbitrary position within the operating range with three degrees of freedom: rotation of the column, swinging of the first arm, and swinging of the second arm. The third arm, which is connected to the column by a series of parallel links and has a condensing system at its tip, always has a constant attitude with respect to the column (that is, vertically downward in this case), and the reference posture of the condensing system is also always constant. . On the other hand, the laser beam sent from the oscillator to the optical system installed above almost coincident with the rotation center of the robot is transmitted to the rear end of the third arm via a transmission system installed outside the robot. The light enters the axis, and then passes through a condensing system provided at the tip of the third arm, and is then irradiated onto the workpiece to be processed.

(Example) Hereinafter, an example of the laser processing robot of the present invention will be described with reference to the drawings.

1 and 2, a column 9 is supported on the base 8 of the robot 1 so as to be rotatable about a vertical axis, and is linked to a drive section comprising a motor and a speed reducer (not shown). On both sides of the frame 10 at the top of the column 9, drive units 11 and 12, each consisting of a motor and a speed reducer, are provided facing each other and concentrically, and a first arm 13 is fixed to the output shaft of the drive unit 11. , a lever 14 is fixed to the output shaft of the rlA moving part 12, and the lever 14 swings around an axis perpendicular to the rotation axis of the column 9.
An L-shaped sunk 16.
Each of the second arms 17 is swingably supported, and a shaft 18 parallel to the shaft 15 is provided at the tip of each second arm 17, and a third arm 19 is swingably supported. The third arm 19 includes a frame 19a and a hollow shaft 19b which is supported by the frame 19a and has a light collecting system 3 at its lower end that is swingable about an axis perpendicular to the axis thereof, and is supported by the frame 19a so as to be able to swing about the axis.
The drive unit 20.21 includes a motor and a speed reducer that drive each independently.

On the other hand, the tip of a rod 23 whose rear end is connected to the tip of the lever 14 with a bearing 22b is connected to the protruding end of the rear end of the second arm 17 with a bearing 22a. The rear end portions of the two arms 17 constitute a parallelogram link. Further, the tip of the rod 25 is connected at its rear end to the frame 10 by a bearing 24a.

It is connected to one end of the L-shaped sink 16 by a bearing 24b, the base end of a rod 27 is connected to the other end of the L-shaped sink 16 by a bearing 26a, and the tip of the rod 27 is connected to the third arm 1 by the bearing 26b.
It is swingably connected to a lever 28 protruding from 9. Moreover, the frame 10, the rod 25, one side of the L-shaped sink 16, the other sides of the first arm 13, the L-shaped sink 16, the rod 27, the lever 28, and the second arm 17 each constitute a parallelogram link. .

Next, an embodiment of a laser beam transmission system will be described in detail with reference to FIGS. 1 and 3. An optical system 6 on a pedestal (not shown) mounted above almost coincident with the robot's rotation axis is connected to an optical axis guided from a laser oscillator (not shown), a mirror A0 with a reflective surface tilted downward by 45 inches, and a transmission beam. It consists of a bearing 8□ which supports the pipe P rotatably as shown by the arrow i in the figure.At the bottom of the transmission pipe P1, there is a mirror town and X facing the optical axis at an angle of 45@. An optical joint E□ is provided which is swingably connected to the bearing B2 as shown by the arrow ■ in the figure, and a transmission pipe P2 is connected concentrically to the output side optical axis.The other end of this transmission pipe P2 Similarly, mirrors M, , M, and bearings B,
There is an optical joint E2 that can swing freely as shown by arrow ■ in the figure, and a transmission pipe P that is concentric with the output side optical axis has a bearing that can swing freely as shown by arrow iv in the figure at the optical axis opening. It is supported via B4. Furthermore, this transmission pipe P.

An optical joint E3, which is also made of mirrors M, , M, and a bearing B5 and is swingable as shown by arrow V in the figure, is provided at the tip of the optical joint E3, and a transmission pipe P4 concentric with the output optical axis is connected to the optical axis opening. The second arm 17 is rotatably supported via a bearing BG as indicated by an arrow Vi in the figure, and its outer diameter is supported by a support 29 fixed to the side surface of the second arm 17. - direction, third arm 19
One end of an optical joint E4 consisting of a mirror M connected to the lower end of the transmission pipe P4 and a bearing B7 is fixed to the upper end of the frame 19a constituting the frame 19a. Also, a bearing B is provided for the frame 19a.

A spur gear 30 is attached to the outer periphery of the upper end of the hollow shaft 19b, which is rotatable through ,
A mirror M is provided which intersects the optical axis at an angle of 451, and a condensing system 3 consisting of a mirror M8, a lens Qe, etc. is swingably supported on the side wall of the hollow shaft 19b via a bearing B. A spur gear 32 provided on the outer periphery of the optical system 3 meshes with a spur gear 33 fixed to the output shaft of a drive unit 21 consisting of a motor and a speed reducer.

Next, the operation of this embodiment will be explained.

In FIG. 1, first, the column 9 is rotated by a drive unit (not shown). Next, when the drive unit 11 is driven,
The first arm 13 performs the swinging motion of ■, and when the drive unit 12 is driven, the second arm 17 performs the motion of the arrow ■ in the figure with the lever 14 and rod 23, and the second arm 17 moves with the above three degrees of freedom. The tip can be three-dimensionally positioned at any position within the operating range. FIG. 2 shows the operating range S on the longitudinal section of the tip of the third arm 19 obtained by the swinging of the first arm 13 and the second arm 17. Since it is connected to the frame IO by two pairs of parallelogram links consisting of 16 and rods 27, it swings about the shaft 18 as shown by the arrow ■' in the figure, and as shown by the chain line in Fig. 2. , the posture is the same at any point within the motion range S in the longitudinal section. Furthermore, when the driving portions 20, 21 provided on the third arm 19 are driven, the condensing system 3 at the tip moves as indicated by the arrows ``■'' and ``■'' in the figure, respectively.

On the other hand, the laser beam transmission system passively operates according to the movement of each degree of freedom of the robot. That is.

The transmission system leading to the pipe P supported by the second arm 17 via the support 29 includes a coaxial rotation i directly below the optical system 6 above the robot, a rocking movement ii of the optical system 1yiu, and an optical joint E.
2 swing ■, coaxial rotation iV of transmission pipe P3, swing V of optical joint E, and coaxial rotation Vi of transmission pipe P4 6
It has a degree of freedom and supports 29 three-dimensional movements,
Follows your posture.

Therefore, in the laser processing robot of the present invention configured as described above, (1) the arm mechanism consisting of the first arm 13 and the second arm 17 whose tip positions change three-dimensionally is further provided with two parallel links; By providing the third arm 19 connected to the frame lO on the upper part of the column 9 via.

The condensing system 3 can always access the workpiece from above, and by changing the length of the third arm 19, it is possible to cut, weld, etc., while escaping the workpiece that is erected.

■ Moreover, at this time, the reference posture of the oscillation V of the focusing system, which determines the angle of depression with respect to the horizontal among the degrees of freedom of the focusing system 3, is relative to the stationary coordinate system (i.e., the workpiece) at all positions within the operating range. Since it is kept constant, the nozzle direction of the condensing system 3 can be restricted by a hard limit or a mechanical stopper on this axis.

■ On the other hand, in the laser beam transmission system, the transmission system from the fixed optical system 6 above the robot to the transmission pipe P4 fixed to the second arm is configured with 6 degrees of freedom using optical joints, etc.
Not only can it follow any movement of the robot, but it can also absorb errors in alignment between the optical axis of the optical system 6 and the robot rotation axis, making installation and movement easier.

(v) Furthermore, since the laser beam is guided to the 37th-A19 axis coaxially with the swing axis 18 of the third arm 19, not only the tip of the arm and the vicinity of the condensing system 3 are made small, but also the third arm Since there is no drive mechanism around the swing axis of the arm 19 and the tip of the protrusion 28 is driven by the rod 27, it is possible to prevent the drive mechanism from intertwining with the laser light transmission system even though there is a laser light path inside the arm.

In this embodiment, the transmission system outside the robot is a multi-joint type with six degrees of freedom, but a telescopic transmission pipe with two to three degrees of freedom of swing may be used at both ends.

In the above embodiment, the third arm 19 is configured to always face downward, but the third arm 19 is
It may also be bent forward and always directed horizontally forward. In this case, the third arm 19 moves in a horizontal state like the arm of a cylindrical coordinate robot, so for example, the third arm 19 moves in a horizontal state around the axis of a turning machine. It has the advantage of being suitable for welding.

〔Effect of the invention〕

According to the present invention, the reference posture of the condensing system at the tip is constant at any position in the operating range, the welding/cutting work does not always interfere with the workpiece, and the optical path is provided inside the arm at the tip of the arm. It is possible to obtain a laser processing robot that is compact, has an optical system and a drive mechanism separated, and is easy to assemble and maintain, and is also highly safe because it can mechanically limit the depression angle of the nozzle direction of the light focusing system. can.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the laser processing robot of the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is an explanatory view showing the operation of the laser processing robot of the present invention, and FIG. 4 1 is a perspective view showing an example of a conventional laser processing robot. 1...Robot 2...Wrist 3...Condensing system 9...Column! 1, 12, 20. 21... Drive unit 14... Lever 16... L-shaped link 13... First arm l7... Second arm 19... Third arm ■... No. 1st axis■...Second axis■...Third axis■'...Fourth axis E1~E,...Optical joint P1~P,...Transmission pipe

Claims (1)

[Scope of Claims] A column that is erected and rotates around a first axis, a first arm that is supported by the column and swings around a second axis that is orthogonal to the first axis, and a second arm that is supported at the tip of the first arm and swings around a third axis that is parallel to the second axis; and a fourth axis that is supported at the tip of the second arm and that is parallel to the third axis. a third arm that is swingably supported by the fourth axis and has a condensing system at its tip that pivots about an axis perpendicular to the fourth axis and swings about an axis perpendicular to the orthogonal axis; and two pairs of parallel link mechanisms connected by levers provided between the column and the third shaft and swingably supported by the third shaft. a plurality of driving means each independently driving degrees of freedom for movement, rotation of the third arm, and swinging of the light focusing system;
a laser transmission path provided near the upper end of the axis of the third arm to bend the laser light transmitted to the optical system and guide it to the tip of the second arm; A laser processing robot comprising: an optical system that guides the laser beam into the third arm; and an optical system that is provided at the tip of the third arm and guides the laser beam to a condensing system.