JPH04158996A - Thermal cutting machine - Google Patents

Abstract

PURPOSE:To improve the quality of a work and to perform unmammed automatic working by reciprocating a receiving base receiving concentrated irradiation of laser beam. CONSTITUTION:When a motor 32 is driven while the work 1 is cut by laser beam, the main frame 23 of an unloading equipment 20 reciprocates in the direction of an arrow A by an eccentric equivalent of a cam 31. Thereby, since a cylindrical body 2, too, mounted on the main frame 23 reciprocates, the opening part 2a of the cylindrical body displaces to the laser beam axis 2a as it receives the laser beam. Consequently, the inner surface of the cylindrical body 2 on the opposite side of the opening part 2a is not irradiated concentrically with the laser beam cut the work 1 and the cylindrical body 2 is not pierced. Consequently, the cylindrical body 2 need not be monitored and unmanned automatic machining can be performed for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a thermal cutting device that cuts a cylindrical workpiece such as a pipe by irradiating it with a laser beam.

[Prior art] When thermally cutting a cylindrical workpiece with a laser beam,
A cylindrical body that serves as a pedestal for the laser beam is inserted in the axial direction of the workpiece to block the laser beam after the workpiece is fused. Further, in Japanese Patent Application Laid-Open No. 53-89098, this cylinder is also used as a means for recovering the melt produced from the workpiece.

FIG. 7 shows a conventional thermal cutting device having the above structure. A cylindrical workpiece 71 is held by chuck claws 73 of a chuck 72, and a laser beam L emission nozzle 74 faces a predetermined position in the length direction of the workpiece 71 to thermally cut the workpiece 71 in the radial direction. It has become.

A cylindrical body 75 serving as a pedestal for the laser beam L is attached to the tip of an arm 76 of the unloading device, and in this state is inserted in the axial direction of the work 71 from the open end of the work 71. This cylindrical body 75 has an opening 75a formed in alignment with the irradiation position of the laser beam L for recovering the molten material.

The apparatus having such a structure thermally cuts the workpiece 71 in the radial direction by irradiating the laser beam L from the output nozzle 74 while rotating the workpiece 71. At this time, the laser beam that melted the workpiece 71 is blocked by the inner surface of the cylinder body 75 on the opposite side to the opening 75a, so that the inner surface of the workpiece 71 on the opposite side to the cut portion of the workpiece 71 is not damaged.

Further, the melt generated from the workpiece during cutting is removed from the opening 75a.
The workpiece 71 falls into the cylinder 75 and is collected.
It will not stick to the inner surface.

[Problems to be Solved by the Invention] However, in the conventional thermal cutting processing device, the laser beam L after cutting the workpiece is directed to the cylindrical body 75 on the opposite side to the opening 75a.
In order to irradiate a single point X on the inner surface with high energy density, the X point is processed and a hole is created. If this hole is opened, the laser beam L will irradiate the inner surface on the opposite side of the workpiece 71, causing a quality problem that may damage the workpiece 71.

For this reason, with conventional equipment, it is necessary for the operator to frequently monitor the cylinder, making it difficult to perform automatic processing without an operator.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a thermal cutting processing device that can prevent holes from forming in a cylindrical body and improve the quality of a workpiece, and also enables unmanned automatic processing. With the goal.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a cylindrical body that serves as a cradle for the laser beam in the axial direction within a cylindrical workpiece that is cut in the radial direction by laser beam irradiation. In the inserted thermal cutting processing device, an opening is formed in the cylindrical body to receive the laser beam that has passed through the workpiece, and the cylindrical body is movable back and forth so that the opening is displaced with respect to the beam axis of the laser beam. This is a thermal cutting processing device characterized by the following.

[Function] The thermal cutting device configured as described above displaces the opening of the cylinder with respect to the beam axis of the laser beam by reciprocating the cylinder, so that the laser beam can not be focused on the inner surface of the cylinder. do not have. This prevents holes from forming in the cylinder.

[Example] Hereinafter, the present invention will be specifically explained by referring to an illustrative example. Note that in each embodiment, the same elements are given the same reference numerals and correspond to each other, thereby omitting redundant explanation.

(First example) FIG. 1 shows the overall configuration of a first embodiment of the present invention.

A holding device 10 for a cylindrical workpiece 1 and an unloading device 2 holding a cylindrical body 2 that serves as a pedestal for a laser beam.
0 are arranged opposite to each other. A holding device 10 for a workpiece 1 includes an XY table 11 that moves in the XY force direction within a plane by numerical control, a rotary table 12 that is placed on the XY table 11 and whose output shaft is rotationally driven, and an output of the rotary table 12. The chuck 13 is attached to a shaft and rotates. The chuck 13 has a plurality of chuck claws 14 on its tip surface, and the workpiece 1 is chucked in a horizontal state by the chuck claws 14. A thermal cutting machine 3 that irradiates a laser beam is installed above the workpiece 1, and its output nozzle 4 is connected to the workpiece 1.
It is facing the cutting position. The holding device 10 positions the cutting part of the workpiece 1 by moving the XY table 11, rotates the workpiece 1 by driving the rotary table 12, and irradiates the workpiece 1 with a laser beam from the output nozzle 4 in this rotating state. thermally cut in the radial direction. 5 is the beam axis of the laser beam irradiated to the workpiece 1, and 6 is the workpiece 1
The workpiece is cut with these axes perpendicular to each other.

The unloading device 20 has a linear guide 22 mounted on a base 21, and a main body 2 on this linear guide 22.
3 are attached. The main body 23 is the base 2
The linear guide 22 is connected to a piston rod of a cylinder 24 attached to the lower surface of the cylinder 24, and moves in the direction of arrow A on the linear guide 22 when the cylinder 24 is driven. This main body 23 is provided with an arm mount 25, and this arm mount 25
An arm 26 extends horizontally in the direction of the holding device 10, and the cylindrical body 2 is attached to the tip of the arm 26. The cylindrical body 2 is inserted in the axial direction of the work 1 so that its axis is coaxial with the axis 6 of the work 1.

FIG. 2 shows the shape of the cylindrical body 2, in which a horizontally elongated opening 2a is formed on the distal end side. The opening 2a receives the molten material generated from the workpiece 1 by thermal cutting with the laser beam, and is located at a position opposite to the beam axis 5 of the laser beam, as shown in FIG. In this embodiment, the cylindrical body 2 is reciprocated in its axial direction by the drive of a reciprocating mechanism 30, and the opening 2a is displaced with respect to the beam axis 5 of the laser beam by this reciprocating movement. It is configured as follows.

The reciprocating mechanism 30 converts rotational motion into reciprocating linear motion using a cam 31. As shown in FIG. A cam 31 is attached to the cam 31. In this case, the motor 32
Pulleys 34 and 35 are attached to the output shaft and the rotation shaft 34 of the bearing box 33, respectively, and
A belt 36 is passed around these pulleys 34, 3'5, so that the rotation of the motor 32 is transmitted to the cam 31. This cam 31 converts the rotational motion of the motor 32 into reciprocating linear motion by contacting a cam floor 37 fixed to the base 21. FIG. 3 shows a cam diagram of the cam 31, in which the eccentricity JIH of the cam changes linearly around a rotation angle of 180°.

In the above configuration, when the motor 32 is driven during cutting of the workpiece 1 with a laser beam, the main body 23 of the unloading device 20 reciprocates in the direction of arrow A by an amount equivalent to the eccentricity of the cam 31 due to the action of the cam 31. As a result, the cylinder 2 attached to the main body 23 also reciprocates in the same direction and by the same amount, so that the opening 2a of the cylinder 2 receives the laser beam and is displaced relative to the beam axis 2a.

Therefore, the laser beam that melted the workpiece l is exposed to the opening 2a.
There is no concentrated irradiation on the inner surface of the cylinder body 2 on the opposite side.
No holes are formed in the cylindrical body 2. Therefore, there is no need to monitor the cylinder 2, and unmanned automatic processing can be performed for a long time.

(Second example) 4 and 5 show a second embodiment of the invention.

In this second embodiment, a cylindrical body 2 serving as a pedestal for a laser beam is moved linearly in a reciprocating manner and rotated in a reciprocating manner within a predetermined angular range, as shown in FIG. 4(a).

(As shown in bl, bearings 41 and 41 are attached to the front and rear of the inside of the arm mount 25.

The bearing 41.41 is mounted in a positioned state by a collar 42 inserted into the arm mount 25 and a cover 43 attached to the tip end surface of the arm mount 25. 26 shaft portions 26a are rotatably inserted.

Further, a motor 44 is fixed to the lower surface of the arm mount 25, and an eccentric joint 45 is attached to the output shaft of the motor 44. On the other hand, a guide arm 47 having a slit 47a at its lower part hangs down from the arm 26, and the pin 46 of the eccentric joint 45 is inserted into the slit 47a of the guide arm 47. The pin 46 of the eccentric joint 45 is eccentric to the output shaft of the motor 44, and when the motor 44 rotates, the guide arm 47 rotates back and forth, and this rotation is transmitted to the cylindrical body 2 via the arm 26. .

Therefore, although the cylinder 2 rotates reciprocally within a predetermined angle range, the width of the opening 2a of the cylinder 2 is set so that it does not come out of the laser beam during the reciprocating rotation. In FIG. 4 (al), 48 is a ring that prevents removal of a C ring or the like that is hooked to the end of the shaft portion 26a of the arm 26.

Such a configuration is added to the first embodiment in which the cylinder body 2 is moved in a reciprocating linear motion, and the reciprocating linear motion by the reciprocating mechanism 30 in the first embodiment and the reciprocating rotational motion in this embodiment are combined. It acts on the cylinder body 2 at the same time.

Figure 5 shows the locus of the laser beam irradiated to the cylinder body 2 when the cycle of the reciprocating rotational motion of the cylinder body 2 is made slower than the cycle of the reciprocating linear motion. Irradiates in a zigzag pattern.

In the second embodiment, the laser beam does not irradiate the cylindrical body 2 only in one straight line, but irradiates it over a wide range. Moreover, by controlling the rotation speed of the motor 44 and changing the cycle of the reciprocating rotational movement, the range can be further expanded. Therefore, the durability of the cylindrical body 2 is increased compared to the first embodiment, and unmanned automatic processing can be performed for a longer period of time.

(Third Embodiment) FIG. 6 shows a third embodiment of the present invention, in which a plurality of small holes 29 are formed in a row in the cylinder 2 at predetermined intervals. Each small hole 2
Reference numeral 9 is an opening that receives the laser beam, and a servo motor or the like is used as the motor 26 (see FIG. 1) to correspond to the pitch of the small holes 29.
The rotation angle is controlled.

That is, the motor 26 intermittently controls the movement of the cylinder so that each small hole 29 faces the beam axis of the laser beam. In this case, the thermal cutting machine 3 (see FIG. 1) is activated in conjunction to irradiate the laser beam when the small hole 29 faces the beam axis.

In the third embodiment, since the irradiation position of the laser beam on the cylinder body 2 changes by moving the small hole 29, it is possible to prevent holes from being made in the cylinder body 2, and long-term unmanned automatic processing is possible. It becomes possible.

[Effects of the Invention] As explained above, the present invention reciprocates the laser beam pedestal to displace the opening of the pedestal with respect to the beam axis, thereby preventing the laser beam from making a hole in the pedestal. This enables long-term unmanned automatic processing.

[Brief explanation of drawings]

1 is a partially cutaway side view showing the overall configuration of the first embodiment of the present invention, FIG. 2 is a side view and a sectional view showing the cylinder, and FIG. 3 is a reciprocating 4(a) and 4(b) are a partially cutaway side view and front view showing the main parts of the second embodiment of the present invention, and FIG. 5 is a cam diagram of the cam for the laser beam. FIG. 6 is a plan view showing the firing locus, FIG. 6 is a perspective view showing a cylindrical body according to a third embodiment of the present invention, and FIG. 7 is a partially cutaway side view showing a conventional device. 1...Workpiece 2...Cylinder 2a...Aperture 5...Beam axis of laser beam 30...Reciprocating mechanism BQ') - Fig. 2 h i a Fig. 3 Rotating mountain

Claims (1)

[Claims] (1) A thermal cutting device in which a cylindrical body serving as a cradle for the laser beam is inserted in the axial direction within a cylindrical workpiece to be cut in the radial direction by laser beam irradiation, receives the laser beam that has passed through the workpiece. forming an opening in the cylinder;
A thermal cutting processing device characterized in that a cylindrical body is movable back and forth so that the opening is displaced with respect to the beam axis of the laser beam.