JPH02207994A - Laser beam machine - Google Patents

Abstract

PURPOSE:To obtain the laser beam machine for decreasing the replacement frequency of a shielding body by providing a transparent shielding body for preventing a molten scattered object from adhering to a condensing lens from an object to be worked between the condensing lens for a laser light and the object to be worked. CONSTITUTION:A laser light 10 converged by a condensing lens 12 is allowed to pass through a transparent shielding body 14, and welding is executed to an object to be worked 21. In this case, a molten scattered object is generated, but the greater part of the scattered object is prevented from being scattered in the direction of the condensing lens 12 by pressurized air from an air blow nozzle 20. Also, it is prevented that a partial scattered object which reaches the direction of the condensing lens 12 adheres to the condensing lens 12. Moreover, since the shielding body 14 is rotated at about 400rpm, its adhesion to the shielding body 14 can also be decreased to the utmost by centrifugal force.

Description

[Detailed description of the invention] [Object of the invention] (Industrial field of application) (Prior art) When a laser beam emitted from a laser oscillator is focused by a condensing lens and irradiated onto a workpiece, the workpiece is Things melt. Undesirable molten metal is scattered from the melt-processed workpiece, and the molten metal may fly to the condenser lens and contaminate the condenser lens. Condensing lenses are expensive, and it is uneconomical to replace them with new ones every time they become contaminated. Therefore, a transparent shielding body, such as a glass plate, is arranged between the condenser lens and the workpiece to prevent melted particles from the workpiece from adhering to the condenser lens.

Although this glass plate is contaminated, it is cheaper to replace than a condenser lens.

However, in order to replace the glass plate, it is necessary to stop the laser processing apparatus, which has the disadvantage that the operation rate of the apparatus decreases.

In addition, laser processing equipment does not exist on its own, but coexists with other complex assembly equipment, safety equipment, and supply materials in a small space, so there is no space to easily replace glass plates, and the work Bad sex.

(Problems to be Solved by the Invention) As described above, replacing the shield in the conventional apparatus has the problem that the operating rate decreases.

Therefore, an object of the present invention is to provide a 1-meter laser processing device in which the frequency of replacing the shield is reduced.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a method in which molten debris from the workpiece is focused between the workpiece and a condenser lens that focuses laser light from a laser oscillator. A laser processing apparatus is provided with a transparent shield for preventing adhesion to a lens, characterized in that the shield is attached so as to be continuously rotatable.

(Function) In the present invention, since the shielding body is attached so as to be able to rotate continuously, even if undesired molten metal is scattered from the workpiece, the amount that adheres to the condensing lens due to centrifugal force is smaller than in the past. There are very few.

(Example) The following describes a laser welding device according to an example of the present invention.
This will be explained with reference to the figures.

FIG. 1 is a schematic cross-sectional view of a laser welding device, in which laser light (lO) emitted from an oscillator is guided to a condenser lens holding cylinder (11) by a light transmission means. Condensing lens holding tube (
, 11) has a condensing lens (12) on the front end with a screw (13)
Fixed by A rotating mechanism for a transparent shield is disposed in front of and opposite to the condenser lens.

This rotation mechanism includes a rotating holding cylinder (15) that fixes the transparent shield (14) to the front end face in the laser beam traveling direction, and a pair of bearings (1B) that rotatably supports this holding cylinder (15).
) (1B), a rubber roller (17) is attached to the rotation holding cylinder (15).
DC motor (18), 1 which transmits rotational driving force via )
A pair of brackets (19) (19) holding a pair of bearings (1B) (1B) are provided, and the bracket (19)
(19), a DC motor (18), and a condensing lens holding cylinder (11) are each fixed on a table (20).

In addition, workpieces are placed in front of the transparent shield (14) at predetermined intervals. Further, an air blow nozzle (22) is arranged near the workpiece (21) and facing toward the workpiece. The operation of the laser welding apparatus of this embodiment configured as described above will be described below.

Laser light (10
) passes through the transparent shield (14) and performs welding at the part to be processed. At this time, melted scattered objects are generated, but most of the scattered objects do not fly toward the condenser lens due to the pressurized air from the air blow nozzle (22).

However, some of the scattered objects may reach the direction of the condenser lens.

In this case, the transparent shield (14) can prevent flying objects from adhering to the condenser lens, and the transparent shield (14)
Since it rotates at a rotational speed of approximately 00 rpm, adhesion to the transparent shield (14) can be minimized due to centrifugal force.

Experiments have confirmed that tgorps or higher is preferable. Incidentally, FIG. 2 shows the relationship between the number of rotations of the transparent shield (14) and the amount of contamination.

It is clear from FIG. 2 that the amount of adhesion decreases as the rotational speed increases.

[Effects of the Invention] As described above, according to the present invention, the frequency of replacing the shield in a laser processing device is reduced, and the industrial value is great.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a laser welding apparatus embodying the present invention, and FIG. 2 is a diagram showing the relationship between the number of rotations of a shield and the amount of contaminants on the shield. DESCRIPTION OF SYMBOLS 10... Laser beam 11... Condensing lens holding tube 12... Condensing lens 13... Screw 14... Transparent shield 15... Rotating holding tube 16... Bearing 17... Rubber roller 18...DC motor
19... Bracket 20... Table 21.
...Workpiece 22...Air blow nozzle agent Patent attorney Noriyuki Chika Yudo Kikuo Takehana

Claims (1)

[Scope of Claims] A transparent shield that is located between a condenser lens that condenses laser light from a laser oscillator and a workpiece, and that prevents melted debris from the workpiece from adhering to the condenser lens. What is claimed is: 1. A laser processing device comprising: the shielding body mounted so as to be continuously rotatable;