JPH10216977A - Machining head of laser beam machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent spatter and dust from sticking to a surface of a condensing lens. SOLUTION: The machining head is arranged with a condensing lens 12 in a lens holder 11 and a guide ring 17 near the condensing lens 12. A gas introducing port 19 introducing assist gas is formed to the lens holder 11 at an outer periphery of the guide ring 17. A guide part 20, by which assist gas is blown from a whole outer periphery of the guide ring 17 to the condensing lens 12 surface, is formed to a tip part of the guide ring holder 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing machine for performing processing such as cutting on a work, and more particularly to a processing head thereof.

[0002]

2. Description of the Related Art Generally, in a processing head of this type of laser processing machine, a condensing lens is disposed at an upper portion in a holder, and a nozzle is attached to a lower end of the holder. Then, the laser beam condensed by the condensing lens is irradiated from the nozzle toward the work, and at the same time, the assist gas is ejected from the nozzle, and the work is subjected to processing such as cutting.

In a processing head of this type of laser processing machine, when a laser beam is transmitted through a condensing lens during processing of a work, the temperature of the condensing lens rises and so-called heat, such as deformation of the condensing lens. Because of the possibility of a lens phenomenon, a processing head having a configuration as disclosed in, for example, Japanese Utility Model Laid-Open No. 63-34590 has been conventionally proposed.

In this conventional configuration, a plurality of gas outlets are formed on the peripheral wall of the holder below the condenser lens. Then, the assist gas is introduced from the gas ejection port into the holder in a direction substantially parallel to the lower surface of the condenser lens, and the condenser gas is cooled by the assist gas.

[0005]

By the way, in this type of processing head, although the assist gas is ejected from the tip opening of the nozzle, spatter and dust generated by laser processing are against the flow of the assist gas. Intrudes into the holder through the tip opening of the nozzle and adheres to the surface of the condenser lens. In this way, if spatter or dust adheres to the condenser lens, the refractive index or the like changes, so it is necessary to disassemble the holder and clean the condenser lens. It was decreasing. Further, depending on the degree of adhesion, the life of the condensing lens has been significantly shortened.

Here, in the processing head described in the above-mentioned publication, the assist gas jet port faces in a direction parallel to the lower surface of the condenser lens. Therefore, the assist gas from each gas ejection port collides with each other below the condenser lens and flows downward. For this reason, since the merging point of the assist gas flow that acts to push back the spatter and dust is located below the condensing lens, the length of the assist gas flow to the tip of the nozzle is shortened, and the spatter and dust are pushed back. It is poor in action and cannot suppress the attachment of spatter and dust to the condenser lens.

In addition, in the conventional processing head, the gas ejection port has a structure in which a plurality of small holes are arranged in a ring shape. And dust stagnate and adhere to the condenser lens.

For this reason, in the conventional processing head,
The troublesome cleaning work described above had to be performed frequently. The present invention has been made by focusing on the problems existing in such a conventional technique. The purpose is to
An object of the present invention is to provide a processing head of a laser processing machine capable of sufficiently exhibiting an effect of preventing adhesion of a spatter or the like to the surface of a condenser lens.

[0009]

In order to achieve the above object, according to the first aspect of the present invention, an annular chamber in which an assist gas is introduced into an inner periphery of a holder between a condenser lens and a nozzle. Was formed between the annular chamber and the holder, and an annular continuous ejection port for blowing the assist gas from the annular chamber toward the entire circumference of the surface of the condenser lens was formed.

According to a second aspect of the present invention, in the processing head of the laser processing machine according to the first aspect, a cylindrical body is provided inside the holder, and the cylindrical body is provided between the cylindrical body and the inner peripheral surface of the holder. An annulus was defined.

According to a third aspect of the present invention, in the processing head of the laser processing machine according to the second aspect, the jet port includes an inclined guide surface formed on the outer peripheral edge of the distal end of the cylindrical body. According to a fourth aspect of the present invention, in the processing head of the laser processing machine according to the third aspect, the lens retainer for supporting the condenser lens is substantially parallel to the inclined guide surface of the cylindrical body. An inclined guide surface was formed.

In the processing head of the laser processing machine according to the first aspect, the laser beam condensed by the condenser lens is irradiated from the nozzle toward the work, and the work such as cutting is performed on the work. Is done. At this time, the assist gas is blown from the annular chamber toward the surface of the condenser lens.

In the processing head of the laser processing machine according to the second aspect, the annular chamber is formed only by providing the cylindrical body. In the processing head of the laser processing machine according to the third aspect, an inclined guide surface is formed on the cylindrical body. Therefore, the assist gas can be uniformly blown along the inclined guide surface toward the entire surface of the condenser lens.

[0014] In the processing head of the laser processing machine according to the fourth aspect, an inclined guide surface is also formed on a lens holder that supports the condenser lens. Therefore, by the cooperative action of the two inclined guide surfaces, toward the entire surface of the condenser lens,
The assist gas can be sprayed more uniformly.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a processing head in a laser processing machine according to the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, the holder 30 of the processing head of this embodiment includes a lens holder 11, a guide ring 17, a sleeve 26, a nozzle holder 15, and a nozzle 16. The lens holder 11 is formed in a cylindrical shape, and a condensing lens 12 is provided between the cylindrical space 10 and the condensing lens upper space 10a via a cylindrical lens receiver 13 and a lens holder 14, respectively. It is supported so that airtightness is maintained. The guide ring 17 as a cylindrical body is fixed to the lower part of the lens holder 11 by a bolt 23 at a flange 17a on the outer periphery thereof.
The guide ring 17 includes an upper cylindrical portion 17b extending from a portion of the flange 17a to immediately near the lens holder 14,
And a lower cylindrical portion 17c extending downward.

The sleeve 26 has a flange 26a on its outer peripheral surface, and a nut 2 screwed into the flange 26a.
5, the sleeve 26 is held. That is, the step 17 d is formed on the outer periphery of the flange 17 a of the guide ring 17.
The step 17d is engaged with the flange 26a of the sleeve 26 from above, and the guide ring 17 and the sleeve 26 are located between the step 17d and the flange 17a.
And a lock pin 24 for preventing relative rotation between the two. The nut 25 has a hook-shaped engaging portion 25a at its upper end, and the engaging portion 25a is engaged with the upper surface of the step portion 17b. Therefore, the step 17b is
The guide ring 17 is held between the lens holder 11 and the sleeve 26 by being sandwiched between the lens holder 11 and the sleeve 26.

The lens holder 11 and the guide ring 1
7, the sleeve 26 and the nozzle holder 15 are
It is attached so that the airtightness between the outside and the outside is maintained.
Further, a lower cylindrical portion 17c of the guide ring 17 is disposed in the sleeve 26.

A pressing ring 27 is provided on the lower surface of the sleeve 26.
Are fixed by bolts 28. The nozzle holder 15 is held between the sleeve 26 and the press ring 27. That is, the flange 15 a of the nozzle holder 15 is
6 is held between the holding ring 27 and the holding ring 27 and is screwed into the holding ring 27 to engage with the flange 15a.
9 is centered. Then, the nozzle holder 15
Is located immediately near the lower end of the guide ring 17.

A nozzle 16 is fixed to a lower portion of the nozzle holder 15 by a screw. And the condensing lens 12
The laser beam condensed in the above is irradiated from the nozzle 16 toward the work W, and the work W is subjected to processing such as cutting.

The guide ring 17 and the lens holder 11
An annular chamber 18 is formed between the annular chamber 18 and the inner peripheral surface. The gas inlet 19 is formed on the outer wall of the lens holder 11 so as to correspond to the lower part of the annular chamber 18, and assist gas is introduced from the gas inlet 19 into the annular chamber 18 on the outer periphery of the guide ring 17. The assist gas outlet 31 is formed between the guide ring 17 and the lens holder 14. The inclined guide surface 20 which forms a part of the ejection port 31 is formed on the outer peripheral edge of the upper end of the guide ring 17, and corresponds to the inclined guide surface 20 in a substantially parallel relationship.
An inclined guide surface 21 that forms a part of the ejection port 31 is also formed on the inner peripheral surface of the nozzle 4.

The assist gas in the annular chamber 18 is blown from the entire outer periphery of the guide ring 17 toward the lower surface of the condenser lens 12 by the cooperative action of the two inclined guide surfaces 20 and 21. I have. After the assist gas is changed in direction on the lower surface of the condenser lens 12, the assist gas is jetted from the nozzle 16 toward the work W through the guide ring 17 and the nozzle holder 15.

Next, the operation of the processing head of the laser processing machine configured as described above will be described. Now, in the processing head of this laser processing machine, the laser beam condensed by the condenser lens 12 is irradiated from the nozzle 16 toward the work, and the work is subjected to processing such as cutting.
At this time, an assist gas is introduced into the annular chamber 18 on the outer periphery of the guide ring 17 from the gas inlet 19 of the lens holder 11, and the assist gas guides the inclined guide surfaces 20, 21 as indicated by an arrow 22. The spout 31
It is sprayed from all over the entire circumference of the surface of the condenser lens 12. Then, the assist gas strikes the lower surface of the condenser lens 12 and is turned downward at the lower surface,
From there, it is jetted toward the workpiece from the nozzle 16 through the inside of the guide ring 17 and the nozzle holder 15 forming the airtight space 10.

As described above, the assisting gas is uniformly blown onto the entire surface of the condenser lens 12 by the guiding action of the two inclined guide surfaces 20 and 21. This reliably prevents spatter and dust generated during processing from adhering to the surface of the condenser lens 12.

Therefore, the effects that can be expected from the above embodiment will be described below. In the processing head of the laser processing machine of this embodiment, the lens holder 11
A guide ring 17 is provided therein to form an annular chamber 18. An ejection port 31 for ejecting the assist gas toward the lower surface of the condenser lens 12 is formed between the guide ring 17 and the lens holder 14. Therefore, as described above, the assist gas can be uniformly sprayed on the entire surface of the condenser lens 12, and it is possible to reliably prevent spatter and dust from adhering to the surface of the condenser lens 12. That is, the assist gas ejected to the lower surface of the condenser lens 12 is inverted at the lower surface, flows downward, and flows in the direction of the nozzle holder 15. Therefore, the confluence of the assist gas flow for pushing back the spatter and dust becomes the lower surface of the condenser lens 12, and the length of the gas flow becomes equal to the total length between the condenser lens 12 and the nozzle 16, so that the The length of the gas stream for pushing back the dust can be increased.

Moreover, the assist gas is introduced into the lower part of the annular chamber 18 and diffused there, and is then ejected from the annular outlet 31 on the upper part. Does not occur, and a uniform gas flow can be secured. Therefore, it is possible to prevent spatter and dust from reaching the condenser lens 12. In the processing head of the laser processing machine of this embodiment, the inclined guide surface 20 is formed on the outer peripheral edge of the distal end of the guide ring 17. For this reason, troublesome processing such as drilling for the gas ejection port 31 is not required, and despite the simple shape, the entire outer periphery of the guide ring 17 is directed toward the entire surface of the condenser lens 12. The assist gas can be sprayed uniformly. Further, the inclined guide surface 2
An inclined guide surface 21 opposing 0 is formed on a lens holder 14 for supporting the condenser lens. Therefore, the number of parts does not increase and the configuration is simplified. In the processing head of the laser processing machine of this embodiment, as described above, the inclined guide surface 2 of the guide ring 17
In order to correspond to 0, an inclined guide surface 21 is also formed on the inner peripheral edge of the front end of the lens holder 14 that supports the condenser lens 12. Therefore, the assist gas can be sprayed more uniformly on the entire surface of the condenser lens 12 by the cooperative action of the two inclined guide surfaces 20 and 21. In the processing head of the laser processing machine of this embodiment, the annular chamber 18 into which the assist gas is introduced is formed only by the configuration in which the guide ring 17 is provided. Therefore, the configuration is simple. In the processing head of the laser processing machine of this embodiment, since the assist gas directly hits the condenser lens 12,
The condenser lens 12 can be effectively cooled.

The present invention can be embodied with the following modifications. -The number of gas inlets 19 should be plural. With such a configuration, the assist gas is diffused more effectively in the annular chamber 18 and a more uniform gas flow can be secured. -The inclined guide surface 21 on the inner peripheral edge of the front end of the lens holder 14 is omitted.

[0028]

The present invention is configured as described above, and has the following effects. According to the first aspect of the present invention, by providing the annular ejection hole for ejecting the assist gas toward the surface of the condenser lens, not only can the condenser lens be effectively cooled, but also the condenser lens can be effectively cooled. It is possible to reliably prevent spatter and dust from adhering to the lens surface.

According to the second aspect of the invention, since the cylindrical body is merely provided in the holder to form the annular chamber, the configuration is simplified. According to the third aspect of the present invention, since the inclined guide surface for guiding the assist gas is formed on the outer peripheral edge of the distal end of the cylindrical body, the assist gas can be sprayed uniformly on the entire surface of the condenser lens.

According to the fourth aspect of the present invention, since the guide surface is provided on the lens holder for supporting the condenser lens, the assist gas is sprayed more uniformly on the entire surface of the condenser lens. be able to.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of a processing head of a laser processing machine according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Holder, 11 ... Lens holder, 12 ... Condensing lens, 13 ... Lens holder, 14 ... Lens holder, 15 ... Nozzle holder, 16 ... Nozzle, 17 ... Guide ring as a cylindrical body, 18 ... Annular chamber, 19 ... Gas inlet, 20, 21
... Slope guide surface, 31 ... Spout.

Claims (4)

[Claims] 1. A condensing lens is provided in a cylindrical holder, and a laser beam condensed by the condensing lens is irradiated onto a workpiece from a nozzle provided at a tip of the holder. In the processing head of the laser beam machine, an annular chamber into which an assist gas is introduced is defined on the inner periphery of the holder between the condenser lens and the nozzle, and the annular chamber is provided between the annular chamber and the holder. A processing head of a laser processing machine that has an annularly continuous ejection port for blowing assist gas from the nozzle toward the entire periphery of the surface of the condenser lens. 2. The processing head according to claim 1, wherein a cylindrical body is provided inside the holder, and the annular chamber is defined between the cylindrical body and an inner peripheral surface of the holder. 3. The processing head of a laser processing machine according to claim 2, wherein said ejection port includes an inclined guide surface formed on an outer peripheral edge of a distal end of a cylindrical body. 4. The processing head of a laser beam machine according to claim 3, wherein an inclined guide surface substantially parallel to the inclined guide surface of the cylindrical body is formed on a lens holder for supporting the condenser lens.