JPH02182392A - Laser beam working head for laser beam machine - Google Patents

Abstract

PURPOSE:To shorten waiting time for working by arranging a valve in inner hole of a torch at tip part of a laser beam working head or in assist gas supplying passage in the laser beam working head. CONSTITUTION:In the case of working process, a piston rod in air pressure cylinder 34 is acted so as to shrink and retreat, and under condition of keeping a rotating valve 44 to close, a solenoid is excited to open a solenoid valve 42. Gas from a gas cylinder 41 is filled up in the working head 20 and the torch 23 is shifted from a waiting position to a positioning position under this condition. At the positioning position, the rotating valve 44 is opened and also irradiation of the laser beam for working through inner mirror device in the laser beam oscillator 31 is started. The assist gas filled up in the head 20 is injected from the tip hole 27 of the torch 23 and at the same time, injected from injection hole 25 toward a beam condenser lens 22 in the head body 21. By this method, at the time of laser beam working, the beam condenser lens 22 for the laser beam is cooled and also invasion of spattering into the working head 20 from the tip hole 27 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a laser processing machine, and particularly to a laser processing head to which an assist gas is supplied.

[Conventional technology]

A laser processing head to which assist gas is supplied in a conventional laser processing machine is connected to a switching valve connected to a gas supply source, such as a gas cylinder, via an assist hose on the stationary side of the laser processing machine.

Then, during processing, the assist gas from the gas cylinder is supplied to each of the laser processing heads by the assist hose via the on-off switching valve that is in the open state. The on/off switching valve is closed when not processing.

[Problem to be solved by the invention]

The laser processing head of a laser processing machine using conventional technology is
1. It is connected to the on-off switching valve on the fixed side of the laser processing machine with an assist hose. The assist hose is long and 1
For example, in a large aircraft, the distance can be more than 10 meters.

Then, when the on-off switching valve is closed, the assist gas in the assist hose between the on-off switching valve and the laser processing head is not used and is wasted. Since the assist hose is long and has a large volume, there is a large amount of leakage.

Moreover, assist gas is leaking inside the assist hose between the on-off switching valve and the laser processing head.
When the on-off switching valve is opened to restart machining, there is a problem in that the assist gas pressure within the laser machining head rises slowly and machining must wait until it reaches a predetermined pressure.

[Means to solve the problem]

The laser processing head of the laser processing machine according to the present invention is provided with an on-off valve in the inner hole of the torch at the tip of the laser processing head or in the assist gas supply passage in the laser processing head.

[For production]

In the case of an on-off valve installed in the inner hole of the torch at the tip of the laser processing head, when the processing laser beam is projected during the laser processing process, the valve is opened, and the processing laser beam is projected from the torch tip hole and assists. During the movement of the laser processing head when gas is injected and processing laser light is not projected, the valve is closed and the ejection of assist gas is cut off. During the teaching laser beam projection and during standby, the assist gas supply source is closed, the blowout of the assist gas is cut off, and the on-off valve is opened.

In the case of an on-off valve provided in the assist gas supply passage in the laser processing head, it is opened only when the processing laser beam is projected, and the assist gas is injected at the same time as the processing laser beam is projected from the torch tip hole. At other times, it is closed and no assist gas is blown out.

〔Example〕

Embodiments of the invention will be described with reference to the drawings.

FIG. 4 illustrates a laser processing machine to which the laser processing head according to the present invention is applied.

On the pallet 2 on the base 1, there are 4 plate-shaped workpieces W, 6 to be fixed at λ.On both sides of the base 1, there are longitudinal direction (X-axis direction) guide rails 3 on the top surface. A guide rail platform 4, 4 is installed. Both ends of the X-axis movable table 5 that straddles the base 1 are supported by the guide rails 3, 3 via ball retainers 6, 6, and the X-axis movable table 5 is supported in the X-axis direction (
It is designed to travel in a direction perpendicular to the paper plane of FIG. 4 by a feeding mechanism controlled and driven by an X-axis servo motor (not shown). The X-axis movable table 5 has a guide rail 7.7 and a feed screw 8 in the Y-axis direction (left and right direction in FIG. 4).
is provided, and a Y-axis movable table 9 is provided with a guide rail 7.
．． 7 and is provided so as to run by a feed screw 8 which is controlled and driven by a Y-axis servo motor 10.

The Y-axis movable table 9 is provided with a feed screw (not shown) which is controlled and driven by the guide rails II, It and the Z-axis servo motor 12 in the Z-axis direction (vertical direction in FIG. 4), and is further movable along two axes. The platform 13 is the guide rail 11.1
1 and is provided so as to run by a feed screw.

7, 11i1! A laser processing head 20 as shown in FIGS. 1, 2, and 3 is mounted on the I-line movable table 13.

Hollow cylindrical head body 2 in laser processing head 20
A condensing lens 22 is provided in the head body 1, and a conical torch 23 is fixed coaxially to the tip of the head body 21. A CO2 laser oscillator 31 for processing and a Ha-Ne laser oscillator 32 for teaching are provided at appropriate locations on the fixed side of the laser processing machine, with the optical axis perpendicular to each other.
means that the laser beams from both laser oscillators 31 and 32 are 1-
-Mirrors 33a and 33b that guide the tip hole 24 of the chi 23
. . , are connected by an optical system consisting of a condenser lens 22 and the like within the head body 21. In particular, in the illustrated example, He-N
A mirror 33a, which is inclined 115 degrees with respect to the optical axis of the e-laser oscillator 32 and is provided at a point perpendicular to the optical axes of both laser oscillators 31 and 32, is connected to a compressed air source (not shown) via an electromagnetic switching valve. It is attached to the piston rod of the pneumatic cylinder 34 for use in the Hc-N e laser oscillator 32, and moves back and forth in the direction of the optical axis of the Hc-N e laser oscillator 32. Thus,
In the forward position, the mirror 33a refracts the laser beam of the He-Ne laser oscillator 32 by 90 degrees and causes it to travel straight toward the next mirror 33b, and in the backward position,
Only the laser beam from the O2 laser oscillator 31 is transferred to the next mirror 33.
Go straight towards b.

Note that both laser oscillators 31. ．． Each of the mirrors 32 has an internal mirror device (not shown) that switches itself to open or block the laser beam from being projected to the outside.

The assist gas supply system is an assist gas supply system in which an electromagnetic switching valve 42 connected to a gas supply #0 source 1, for example, a gas cylinder 41, and a head main body 21 are bent and expanded in both the X-axis and Y-axis directions. They are connected by a hose 43.

The head main body 21 is provided with a passage 26 that communicates between a supply port 24 that is open on the outer circumferential surface and to which the assist hose 43 is coupled, and an injection port 25 that is open on the inner circumferential surface and that faces the condensing lens 22. There is.

A one-turn valve 44 is provided near the tip of the torch 23,
The tip hole 27 is opened and closed. To describe the rotary valve 44 more specifically, the rotary valve 44 is connected to the torch 2.
3 so as to be rotatable perpendicular to the axis of the torch 23,
Its end protrudes from the outer peripheral surface of the torch 23 and the one-turn valve 44
A rotating arm 45 is fixed to the protruding end of the rotary arm 45 . The rotary valve 44 has a valve hole 4 having a shape that is continuous with the inner peripheral surface of the torch 23 only when the rotary valve 44 is in the open position.
6 is formed perpendicular to the valve rotation axis.

A pneumatic cylinder 53 for operating a rotary valve connected to a compressed air source 51 via an electromagnetic switching valve 52 is attached in the axial direction to the side surface of the head body 21, and is connected to the tip of a piston rod 54 protruding below the pneumatic cylinder 53. The tip of the rotating arm 45 is connected to a transmission wire 56 that is guided through a wire hose 55.

Instead of providing the rotary valve 44 near the tip of the torch 23,
An electromagnetic switching valve 47 may be provided in the passage 26, especially in the supply 24.

The operation and function of the above laser processing machine will be explained.

A plate-shaped workpiece W is placed and secured on the pallet 2 of the base 1-L. The X-axis movable base 5 travels on the guide rails 3, 3 in the X-axis direction (perpendicular to the plane of the drawing in FIG. 4) via the feed mechanism by driving the X-axis servo motor under the control of a control device (not shown). At the same time, the Y-axis movable base 9 is moved in the Y-axis direction (the fourth
It runs on the guide rail 7.7 in the left-right direction in the figure.

Therefore, the torch 23 of the laser processing head 20 is moved to a desired position on the surface of the workpiece W.

Draw the desired trajectory.

When the laser processing head 20, that is, the first chip 23 is in the standby position O shown in FIG. The supply of assist gas is stopped, and the assist gas is not within the laser processing head 20 and does not flow out from the torch 23.

When starting the teaching process and the machining process, each laser oscillator is activated in advance, and the laser beam is blocked from being projected to the outside by an internal mirror device.

First, in the case of the teaching process, at the standby position 0, with the 'ir1 magnetic switching valve 42 closed, the head main body 21
While stopping the supply of assist gas to the
2, actuates the pneumatic cylinder 53, extends the piston rod 54, rotates the rotating arm 45 via the transmission wire 56, and opens the rotary valve 44. Furthermore.

An electromagnetic switching valve is switched to a compressed air source (not shown), and the piston of the pneumatic cylinder 34 is operated to extend, the mirror 33a is moved to the forward position, and the internal mirror device releases the projection of the laser beam.

Then, the teaching laser beam travels straight toward the mirror 33a, is refracted 90 degrees by the mirror 33a, and then passes through the mirror 33a.
b, is reflected by the mirror 33b, passes through a predetermined optical path, enters the head body 21, is focused by the condensing lens 22, and is irradiated from the tip hole 27 of the 1-chi 23.

Then, as described above, the torch 2:1 starts from the waiting position [io] on the surface of the workpiece W, passes through the positioning positions Al, A2, and then moves to the waiting position 0 as shown in FIG. Teaching is performed by performing positioning movement and desired locus (for example, six circular movements in FIG. 5) until the position returns to .

Next, in the case of the machining process, at the standby position ○, the electromagnetic switching valve is switched to a compressed air source (not shown), the piston of the pneumatic cylinder 34 is operated to retract, and the mirror 33
When the rotary valve 44 is in the forward position and the rotary valve 44 remains closed, the solenoid 1 of the electromagnetic switching valve 42 is energized and opened. Then, the assist gas from the gas cylinder 41 fills the laser processing head 20 at a predetermined pressure. In this state, the torch 23 is positioned and moved from the standby position ◯ to the positioning position Al.

At the positioning position A1, the electromagnetic switching valve 52 is switched, the pneumatic cylinder 53 is operated, the piston rod 54 is extended, and the rotary arm 45 is rotated via the transmission wire 56, thereby opening the rotary valve 44. At the same time, the internal mirror device of the CO2 laser oscillator 31 releases the projection of the processing laser beam.

Then, the assist gas filling the laser processing head 20 is ejected from the tip hole 27 of the torch 23, and at the same time, the assist gas from the gas cylinder 41 is ejected from the injection port 25 toward the condensing lens 22 into the head body 21. Injected. As a result, the condenser lens 22 onto which the laser beam is projected during laser processing is cooled, and the spud is prevented from entering into the laser processing head 20 through the tip hole 27.

The processing laser beam then travels straight toward the mirror 33b, is reflected by the mirror 33b, passes through a predetermined optical path, enters the head body 21, and enters the condenser lens 22, which is cooled by the injected assist gas. The light is focused and irradiated from the tip hole 27 of the torch 23 to the positioning position AI on the surface of the workpiece W, and processing is started.

Then, as described above, the torch 23 moves along a desired trajectory (eg, circular in FIG. 5) and returns to the positioning position AI, and the workpiece W is cut into the desired shape (circular).

Therefore, the internal mirror device of the CO2 laser oscillator 31 blocks the projection of the laser beam for processing, and the um switching valve 52 is switched, the pneumatic cylinder 53 is operated, the piston rod 54 is retracted, and the to rotate the rotating arm 45 and close the rotary valve 44.

Then, the assist gas does not eject from the tip hole 27 of the head body 21 while remaining filled at a predetermined pressure. Then, in this state, the torch 23 is positioned and moved from the positioning position A1 to the positioning position A2.

Thereafter, the laser processing and positioning movement as described above are repeated, and, for example, six circular cuts are performed as shown in FIG. 5.

Then, the torch 23 returns from the positioning position 6 to the standby position O in the same manner as the positioning movement.

〔Effect of the invention〕

According to this invention, the on-off switching valve connected to the gas supply source on the stationary side of the laser processing machine is always kept open during the processing process, and while the torch is moving between two positions,
The on-off valve in the laser processing head is closed, and the assist hose and laser processing head are filled with assist gas.
Assist gas pressure is maintained. Therefore, when re-projecting the laser beam, the opening/closing valve is opened and processing is performed, but at that time, the injection state of the assist gas is immediately set to the predetermined state from the beginning, so that the processing time can be shortened.

Moreover, when the on-off switching valve is closed, a large amount of assist gas in the long assist hose or processing head between the on-off switching valve and the laser processing head is not used and is not wasted. In particular, when drilling holes such as small holes requires a lot of machining, the assist gas loss of 50% becomes about 0 to 5%.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of a laser processing head of a laser processing machine according to an embodiment of the present invention, and FIG. 2 is a partial cross-sectional view of a laser processing head of a laser processing machine according to an embodiment of the present invention. Partial cross-sectional side view of No. 3 +”J is I1 in Fig. 2.
4 is a partial front view of the laser processing machine according to the embodiment of the present invention; FIG. 5 is a side view of the laser processing head of the laser processing machine according to the embodiment of the present invention; This is a saltwater map.

Claims (1)

[Claims] A laser processing head of a laser processing machine, characterized in that an on-off valve is provided in the inner hole of the torch at the tip of the laser processing head or in the assist gas supply passage in the laser processing head.