SU1756075A1 - Method of laser cutting - Google Patents

Abstract

Use: mechanical engineering. SUMMARY OF THE INVENTION: A cut is formed by focused laser radiation of constant power and a stream of gas, and a cutting speed for each thickness is determined from a treatment zone signal, corresponding to the formation of edges without breaks and burrs. To increase productivity, a cut is formed on a workpiece of variable thickness in a single pass, and a signal from the treatment area is used to adjust the cutting speed depending on the thickness of the workpiece. The signal used is the direction of the outflow of the gas stream from the cut. 1 з п. Ф-л, 2 silt,

Description

The invention relates to a technique for laser processing of materials, mainly cutting sheet blanks.

The aim of the invention is to improve the performance of the process mode determination process.

The goal is achieved by performing a process of cutting blanks of variable thickness in a single pass with focused laser radiation of constant power and a gas jet. The signal from the cutting zone limits the cutting speed and adjusts it depending on the change in the thickness of the workpiece, avoiding formation of burrs and burrs at the edges of the cut. The direction of jet outflow from the cut can be used as a signal from the cut zone.

The achievement of this goal is ensured by the fact that the laser radiation depends on the thickness of the workpiece to determine the desired speed of cutting sheet material when the processing quality is achieved by performing only one cut of a variable thickness and controlling the cutting speed depending on the signal level from the processing area.

FIG. 1 shows an apparatus for carrying out the method; in fig. 2 is a graph of the speed of movement of the workpiece from its thickness.

A workpiece 3 of variable thickness of a given material is placed on the table 1 of the laser setup, having a controlled drive 2 of movement along the cutting direction. When used as

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the signal from the zone of processing the gas jet outflow direction from the cut, pneumatic sensors 4 coaxially with laser radiation with lead and lag in the direction of cutting are located under the table. The sensors are connected to the signal analyzer 5, the table actuator 6, and the recorder 7. Radiation of constant power sufficient to cut the workpiece of the greatest thickness is supplied and the table 1 is turned on with blank 3. Regardless of the change in the thickness of the workpiece, the cutting speed is maintained at the level providing cut quality (without burr and burr), using the signal from sensors 4 to control the operation of the table drive. The dependent change in cutting speed on the thickness of the workpiece, recorded by the recording device 7 and set in accordance with the thickness values, is the desired set of laser cutting modes for the material of workpieces of various thicknesses.

Example. We chose processing modes for billets of various thickness (1-10 mm) from StZ steel. For processing, we used a COA emitter with a power of 0.8 kW in a single-mode mode, a focusing lens made of KCI salt with a focal length of 200 mm. The working gas is oxygen with a pressure of 2 atm. As sensors used

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pneumatic diaphragm sensors mounted at a distance of 0.8 mm from the radiation axis. The initial movement speed of the blanks was 12 m / min. The blank is made in the form of a wedge with a minimum thickness of 0.5 mm and a maximum of 11 mm with a length of 400 mm. The dependence obtained when making a single pass along the direction of changing the thickness of the workpiece (Fig. 2) allows you to choose high-quality cutting modes for sheet blanks made of Stz steel of various thickness (from 1 to 10 mm) with a constant radiation power of 800 W and varying values speed.

Claims (2)

Claim 1. Method for determining the laser cutting mode of workpieces of various thickness, in which the cut is formed by focused laser radiation of constant power and a stream of gas and a signal from the treatment area sets the cutting speed for each thickness, corresponding to the formation of edges without burrs, characterized by that, in order to increase productivity, a cut is formed on a workpiece of variable thickness in a single pass. 2. A method according to claim 1, characterized in that a change in the direction of flow of the gas stream from the cut is used as a signal. ; & .. W & / SS / S /// 7 / V 1 U X n / ftutt