JPH0970680A - Laser working device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely focus a laser beam on a face to be worked by providing with a head part holding means which presses a condenser lens side of a working head part main body to members to be worked without necessitating the precise position and attitude control. SOLUTION: The head part holding means 5 is still continued to lower after a flat contacting face 11 of a condenser lens 9 is brought into contact with the face 19 to be worked, and the working head part main body 3 is inserted into the inside of the head part holding means 5. An elastic force is produced by providing a pressing mechanism 13 between the head part main body 3 and the holding means 5. Members 21a and 21b to be worked are pressed by the condenser lens 9 owing to the elastic force. When the head part holding means 5 is further lowered, a shutter switch 17 arranged to the holding means 5 is pushed by the upper face part of the working head part main body 3, a shutter 16 arranged between an optical fiber 7 and the condenser lens 9 is released. The face 19 to be worked is irradiated with the laser beam L through the condenser lens 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus, and more particularly to a laser processing apparatus for irradiating a processing member with laser light and processing the member by the energy of the laser light.

[0002]

2. Description of the Related Art Conventionally, a laser processing apparatus shown in FIG. 8 has been used. That is, the laser processing device 51 includes an optical fiber 57 for guiding the laser light L from a laser light source (not shown) and a convex lens for focusing the laser light L from the optical fiber 57 on the processing surface 69. 59 and a processing head portion main body 53 that holds the optical fiber 57 and the convex lens 59. Further, further, in the processing head main body 53 of the laser processing device 51,
A guide roller mechanism 61 for maintaining a distance between the processing member 71a and the processing surface 69 at a predetermined amount is provided.

Explaining these in more detail, the processing head portion main body 53 of the laser processing apparatus 51 is composed of a hollow cylindrical tube, and the side facing the processing member 71a is opened. Then, as shown in FIG. 8, an optical fiber 57 for emitting the laser light L generated in the laser light source is introduced in the center of the inside of the processing head main body 53. That is, the optical fiber 57 is installed in the central axis region of the processing head main body 53.

A convex lens 59 as shown in FIG. 8 is arranged inside the processing head main body 53 and in front of the laser light irradiation side of the optical fiber 57. That is, the laser light L emitted from the optical fiber 57 is condensed by the convex lens 59, and is then emitted to the surface of the processing member 71a through the opening of the processing head main body 53. This convex lens 59 has a focal length of about several tens [mm].
It is of a degree.

On the side surface of the processing head main body 53,
A guide roller mechanism 61 is provided to keep the distance between the tip of the processing head main body 53 and the processing surface 69 constant. More specifically, in the guide roller mechanism 61, a rod-shaped member is disposed on the side surface of the processing head portion main body 53, and the tip end portion thereof projects from the opening of the tip end portion of the processing head portion main body 53. A rotatable roller is attached to the tip of this rod-shaped member.

The operation of the laser processing apparatus 51 of the conventional example configured as described above will be described. As shown in FIG.
The processed members 71a and 71b are arranged in a stacked manner, and each member is fixed by a jig 55 in order to enhance the close contact between them.

Then, the machining head main body 53 installed in the industrial robot (not shown) approaches the machining surface 69 of the machining member 71a, and the above-mentioned guide roller contacts the machining surface. Then, the processing head main body 53 is accurately positioned at the processing position on the processing surface 69, and the laser light L is emitted. At this time, the laser light L is condensed by the convex lens 59 and focused on the processed surface 69. As a result, the members of the processed portion are melted and the two are integrally joined.

Further, at the time of irradiation with the laser beam L, in order to protect the convex lens 59 and the opening of the processing head main body 53, a shield gas made of an inert gas such as argon or nitrogen is introduced from the inside of the processing head main body 53. Is jetted.

[0009]

However, in the above conventional example, the following inconveniences have occurred. That is, the laser processing apparatus according to the conventional example has a disadvantage that it is necessary to precisely perform the position control and the attitude control so that the laser beam is properly focused on the processing surface. Specifically, since the lens and the processing surface are separated from each other, when the processing head body is tilted, the distance to the processing surface is slightly changed even if the guide roller is mounted.

Further, in the processing portion area, the members to be processed are separated from each other, and a special jig is required to suppress the so-called floating state of the members, which is a disadvantage.

Furthermore, in order to protect the convex lens and the front end region of the processing head main body, it is necessary to spray a predetermined shield gas toward the processing region. However, injecting this shield gas results in rapid cooling of the processed portion, which causes a problem that a so-called solidification crack phenomenon easily occurs.

[0012]

It is an object of the present invention to provide a laser processing apparatus capable of improving the disadvantages of the conventional example, and in particular, requiring no precise position control or attitude control of the processing head main body and capable of reliably processing a processing member. The purpose is to do.

[0013]

In order to achieve the above-mentioned object, in the invention described in claim 1, the laser processing apparatus is
A condenser lens installed facing the processing surface of the processing member,
An optical fiber that is provided along the center line of the condenser lens, guides laser light, and radiates and outputs the laser beam toward the central portion of the condenser lens; and a processing head portion main body that holds the optical fiber and the condenser lens. Is equipped with. In addition, the condensing lens is provided with a flat abutting surface that abuts the machined surface of the machined member through an oil film, holds the machining head body, and uses the condensing lens side of the machining head body as a machining member The head portion holding means for pushing toward is equipped.

In the invention according to claim 2, the head holding means is equipped with a pressing mechanism for appropriately pressing the condensing lens side of the processing head main body against the processing member. The configuration is the same as that of the invention described in claim 1.

According to the invention of claim 3, the invention according to claim 1
In the laser processing apparatus described above, the head holding means,
The configuration is such that an oil injection mechanism for injecting oil for forming an oil film is provided between the condenser lens and the processing member.

Further, in the invention described in claim 4, a hemispherical lens is used as the condenser lens, and the other structures are the same as those in the invention described in claim 1, 2, or 3.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. First, in FIG. 1, a laser processing apparatus 1 is provided with a light condensing device provided facing a processing surface 19 of a processing member 21a. A lens 9, an optical fiber 7 provided along the center line of the condenser lens 9 for guiding the laser light L and radiating and outputting the laser light L toward the central portion of the condenser lens 9, the optical fiber 7 and the condenser lens. Processing head body 3 for holding 9
And Further, the processing member 2 is attached to the condenser lens 9.
A flat contact surface 11 that contacts the processing surface 19 of 1a, 21b via an oil film 23 is provided, and the processing head main body 3 is held and the condenser lens 9 side of the processing head main body 3 is connected to the processing member 21a, It is equipped with a head portion holding means 5 which is pressed toward 21b.

Explaining the above configuration in more detail, the processing head portion main body 3 is composed of a cylindrical hollow member, and one end on the side facing the processing members 21a and 21b is opened. Then, in the opening of the processing head body 3, FIG.
Also, a hemispherical condenser lens 9 as shown in FIG. 2 is provided. More specifically, the spherical surface is processed into the head body 3
The flat contact portion 11 is arranged so as to face the outer side of the processing head portion main body 3, that is, the processing members 21a and 21b side.

An optical fiber 7 for introducing the laser light L from a laser light output unit (not shown) into the condenser lens 9 is arranged on the central axis portion of the processing head main body 3. The optical fiber 7 is made of a glass material, and internally reflects the laser light L and irradiates the laser light L from the tip to the outside. Further, the laser light L emitted from the optical fiber 7
Is incident on the spherical surface side of the condensing lens 9 arranged at the tip of the processing head body 3, and is emitted from the flat contact surface 11 side. Further, between the optical fiber 7 and the condenser lens 9, a shutter 16 that blocks and transmits the laser light L at a predetermined timing is provided. The shutter 16 opens and closes according to the operation of a shutter switch 17 described later. The shutter 16 is an electromagnetic shutter. However, the shutter is not limited to the electromagnetic type and may be a mechanical type.

An oil injection mechanism 15 for injecting oil onto the processing surfaces 19 of the processing members 21a and 21b is provided on the outer peripheral surface of the processing head main body 3. This oil injection mechanism 15
Is made of a pipe-shaped member, and its tip is bent toward the above-described condenser lens 9. In addition, the oil injection mechanism 1
Reference numeral 5 is connected to an oil storage portion (not shown), and at the time of laser processing, oil is appropriately sprayed between the condenser lens 9 and the processing surface 19.

Next, the head holding means 5 for holding the processing head body 3 will be described. Head part holding means 5
Like the processing head main body 3, has a hollow cylindrical shape. However, the inner diameter thereof is formed to be slightly larger than the outer diameter of the processing head body 3. The processing head body is slidably fitted inside the head holding means 5.

Processing head body 3 and head holding means 5
As shown in FIGS. 1 and 3, a pressing means 13 and a shutter switch 17 each of which is composed of a predetermined shaft member and a spring member are disposed between and. One end of the shaft member of the pressing means 13 is fixed to the processing head main body 3, while the other end is inserted into a shaft hole provided on the head holding means 5 side. Then, when the mutual distance between the processing head main body 3 and the head holding means 5 changes, the other end of the shaft member enters the shaft hole. A spring member having a predetermined spring constant is attached to the shaft member.

A shutter switch 17 is arranged between the processing head main body 3 and the head holding means 5. The shutter switch 17 is fixed to the head unit holding means 5 side, and on the side facing the processing head unit body 3,
A button for turning on the switch is provided, and the shutter is normally closed to block the laser light. Especially, the position where the switch is turned on is related to the spring constant of the spring member,
The condenser lens 9 is set at a location where an elastic force required to appropriately press the processing members 21a and 21b is generated.
The shutter switch 17 is used to match the timing of opening and closing the shutter 16 described above.

Next, the operation and function of the laser processing apparatus 1 configured as above will be described with reference to the drawings.

First, the laser processing apparatus 1 is installed in an automatic machine such as an industrial robot as shown in FIG. Then, as shown in FIG. 5, the processing member 21a is positioned near the portion to be processed. In particular, FIG. 5 shows a case where an automobile door is processed. However, the application is not limited to these, and can be widely used when welding a plurality of members.

Next, the machining head main body 3 set at an appropriate position approaches the machining surface 19 substantially vertically (S).
1). At this time, on the surface of the processed surface 19, the oil injection mechanism 1
5, oil is applied in advance so that an oil film is formed between the condenser lens 9 and the processed surface 19 (S).
2). Then, the flat contact surface 11 of the condenser lens 9 contacts the processing surface 19 (S3).

The flat contact surface 11 of the condenser lens 9 is the processed surface 1.
Even after contact with 9, the head holding means 5 continues to descend,
As a result, the processing head main body 3 causes the head holding means 5 to move.
Enter inside. That is, the distance between the processing head body 3 and the head holding means 5 becomes short. At this time, between the machining head body 3 and the head holding means 5,
As shown in FIG. 3, since the pressing mechanism 13 described above is provided, an elastic force proportional to the decrease amount of the mutual distance is generated. Then, due to this elastic force, the condenser lens 9 presses the processing members 21a and 21b (S3). This allows
Before processing, even if there is a gap between the processing members 21a and 21b, they can be brought into close contact with each other appropriately. Therefore, it is not necessary to separately provide a special jig or the like for bringing them into close contact with each other.

When the head holding means 5 is further lowered, the upper surface of the processing head body 3 pushes the shutter switch 17 arranged on the head holding means 5 (S4).
When this shutter switch is pressed, the lowering of the head unit holding means 5 is stopped, and at the same time, the shutter 16 disposed between the optical fiber 7 and the condenser lens 9 is opened.
Then, the laser light L emitted from the optical fiber 7 passes through the condenser lens 9 and is applied to the processing surface 19 (S
5).

Next, referring to FIG.
The laser light L is incident on the condenser lens 9 as substantially parallel light. Then, the light is refracted at the spherical surface of the condensing lens 9 formed in a hemispherical shape. The refracted laser light L converges into a small spot near the flat contact surface 11 of the condenser lens 9. Further, the condenser lens 9
Even when entering the oil film 23 from the above, a certain refraction phenomenon occurs, and the focus is formed on the processed surface. That is, the curvature of the condenser lens 9 is determined by the wavelength of the laser light L, the refractive index of the condenser lens, the refractive index of the oil film, the thickness of the oil film, and the like. In other words, by setting these values accurately in advance, it is possible to reliably perform laser processing without performing precise position control or attitude control of the processing head main body 3.

When the laser light L is focused on the processed surface 19,
Heat is generated by the energy of the laser light L, and the processing member 21a is heated. Then, due to this heat, the processing member 21a is melted, and the melting region 25 is expanded to the processing member 21b. At this time, since the condenser lens 9 is protected by the oil film 23, adhesion of the melted member is prevented.

Subsequently, the processing head portion main body 3 is processed by the processing surface 1
Rise from 9. Therefore, the shutter switch 17 is turned off (S6), and the shutter 16 is closed. This allows
The temperature of the melting region 25 decreases, and the processing members 21a and 21b are joined (S7).

Further, the laser processing apparatus is, as described above,
Since precise position control and attitude control are not required, an operator may directly hold the laser processing apparatus 1a in his hand and inject the oil spray 27 as shown in FIG.

[0033]

Since the present invention is constructed and functions as described above, according to the invention of claim 1, it is possible to reliably perform precise position control and attitude control of the machining head main body with respect to the machining member. In addition, the laser light may be focused on the processed surface. As a result, there is an excellent effect that high quality laser processing can be performed with a simple structure and control.

According to the second aspect of the invention, the condenser lens directly presses the processed member via the oil film. Therefore, it is possible to surely bring the processed members into close contact with each other without using a special jig or the like, and it is possible to perform a high quality laser processing, which is an excellent effect. Also,
Since the oil film is interposed between the processing member and the condenser lens,
Adhesion of the processing member melted by the laser processing to the condenser lens is appropriately prevented. In addition, even if the processing member adheres to the condenser lens, it is possible to easily remove the processing member, which is an excellent effect.

Further, according to the third aspect of the present invention, since the oil jetting mechanism is provided near the tip of the processing head main body, an appropriate oil film is always provided even when continuously laser processing a wide range. It is formed on the processed member. As a result, when the laser processing apparatus is mounted on an automatic machine or the like, the working efficiency is improved, which is an excellent effect.

Further, according to the invention of claim 4, since the hemispherical lens is used as the condenser lens, the focal length is very short, and more specifically, the focal point is formed in the vicinity of the condenser lens. Therefore, even if the flat contact surface of the condenser lens is brought into contact with the processing member, there is an excellent effect that the processing member surface is focused and laser processing can be performed.

Further, since the flat contact surface of the condenser lens contacts the processed member via the oil film, the oil film between the condenser lens and the processed member is kept uniform, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a condenser lens and a processing portion of the laser processing device disclosed in FIG.

3 is a cross-sectional view showing a pressing mechanism of the laser processing apparatus disclosed in FIG.

FIG. 4 is a diagram showing an industrial robot equipped with the laser processing apparatus disclosed in FIG. 1;

FIG. 5 is a diagram showing a processing head body and a processing member.

FIG. 6 is a diagram showing a state in which processing is performed by a portable laser processing device.

FIG. 7 is a flowchart showing each step of laser processing.

FIG. 8 is a sectional view showing a conventional laser processing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser processing apparatus 3 Processing head main body 5 Head holding means 7 Optical fiber 9 Condensing lens 11 Flat contact surface 13 Pressing mechanism 15 Oil injection mechanism 19 Processing surfaces 21a, 21b Processing member 23 Oil film L Laser light

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area B23K 26/08 B23K 26/08 B 26/14 26/14 Z

Claims (4)

[Claims] 1. A condenser lens provided so as to face a processing surface of a processing member, and a laser lens provided along a center line of the condenser lens for guiding laser light and directed toward a central portion of the condenser lens. In a laser processing apparatus comprising an optical fiber for radiating and outputting, and a processing head portion main body for holding the optical fiber and the condenser lens, the condenser lens is applied to the processing surface of the processing member via an oil film. A flat contact surface is provided to be in contact with the processing head portion, and head portion holding means for holding the processing head portion main body and pressing the condensing lens side of the processing head portion main body toward the processing member is provided. Laser processing equipment. 2. The laser according to claim 1, wherein the head portion holding means is equipped with a pressing mechanism for appropriately pressing the condensing lens side of the processing head portion main body against the processing member. Processing equipment. 3. The laser processing apparatus according to claim 1, wherein the head holding means is equipped with an oil injection mechanism for injecting oil for forming an oil film between the condenser lens and the processing member. A laser processing device characterized in that 4. The laser processing apparatus according to claim 1, wherein a hemispherical lens is used as the condenser lens.