LASER OSCILLATION CONTROLLER

Abstract: The output of the laser oscillator is controlled by a G-code in a programme of instruction means and by other addresses. The output power is instructed by an address, the frequency is instructed by an address, and the pulse duty is instructed by an address, and the pulse duty is instructed by an another address. The instruction data are given to a high-frequency power source to control the laser output. The output of the laser beam is controlled by the G-code, and the machining is effected automatically without need for the operator to set the machining conditions for every machining step.

Description: The present invention relates to a laser oscillation control system, and more particularly to a laser oscilation control system wherein an output of the laser oscillator is controlled by a G-code. Background Art Today, a laser machining equipment with a numerical control system is widely used. In such a laser machining equipment, an X-Y table is controlled by the numerical control system, a work is set in position on the X-Y table so that the work is subject to machining such as cutting by a laser beam emitted from a stationary laser oscillator. In this type of the laser machining equipment, it is a widely practiced system that an output of laser is increased or decreased by a dial on an operation panel or the like mounted on the laser machining equipment at the time of machining. In such a system, however, setting of the laser output by the dial has to be changed every time a different kind of a work is loaded, and it is troublesome for the operator to be frequently involved in such a setting job. It is an object of the present invention for solving the aforesaid problem to provide a laser oscillation control system wherein an output of a laser oscillator is controlled by a G-code. According to the present invention, there is provided a laser control system comprising: a laser oscillator for performing laser machining by controlling an X-Y table with a numerical control system, characterised in that: a machining operation is designated by a G-code with a power output command, a pulse frequency command and a pulse duty ratio for controlling the output of the laser oscillator. With the control system, the output of the laser oscillator is controlled with the program, and so the operator is not required to set the output each time a different kind of work is loaded. In the drawings: Fig. 1 is a block diagram of a laser oscillator control system according to the present invention. An embodiment of the present invention will hereinafter be described in specific details with reference to the drawing. Fig. 1 is a block diagram of a laser oscillation control system according to an embodiment of the present invention, wherein denoted at 1 is a command means of a program or the like such as a paper tape reader or a cassette tape reader or the like as an input device. Denoted at 2 is a numerical control system, which reads and interprets the program from the command means and applies the command to other units. The program is commanded in the following form: G01 X2000 Y3000 F4000 S600 P1000 Q5 CR where "G01" is a G-code to represent a linear cutting mode. Besides, other G-codes such as "G02" and "G03" for circular cutting can be used. "X2000" and "Y3000" are respectively incremental command values to represent a movement of the table, but the command values can also be used for an absolute command. F represents a moving speed of the table or a machining speed. "S600" represents an output of a laser beam, of which "600" denotes that the output is 600W. "P1000" represents a frequency of pulse output, which is 1000Hz. "Q5" represents a duty ratio of the pulse, that is, a percentage of a pulse-on time to one cycle of a pulse, which is 5% in this case. Denoted at 3 and 4 are servoamplifiers, which respectively receive the commands concerning an X-axis and a Y-axis from a numerical control system 2 to drive servomotors. Denoted at 5 and 6 are the servomotors, which are driven in response to commands from servoamplifiers 3 and 4 to move an X-Y table (not shown). Denoted at 7 is the high-frequency power supply, which outputs a high-frequency pulse power of several MHz. In this case, a power S, a pulse frequency P and a duty ratio Q are determined according to commands from the numerical control system 2. Denoted at 8 is a laser tube wherein laser medium gas circulates. Denoted at 9a and 9b are electrodes, through which the high-frequency pulse from the high-frequency power supply is supplied to the laser tube where electric discharge is caused by the laser medium gas, and a laser beam is oscillated and amplified. Denoted at 10a, 10b and 10c are on-off valves for assist gas, which are controlled by commands from the numerical control system 2. For instance, the commands for controlling turning on and off of the assist gas include: G24 P1 CR where "G24" represents a G-code for controlling the assist gas, and "P1" a command for turning on a nozzle of a first assist gas. In such a manner, not only the commands for controlling the power, the pulse frequency and the duty ratio of the laser beam but also the commands for controlling the assist gas can be given by the G-code, so that an operator is not required to set machining conditions. In the case of the above embodiment, the command for machining operation is given through the paper tape, it may be inputted directly to a memory through a keyboard or the like. As explained above, according to the present invention, the output of the laser beam is controlled by the G-code, so that the machining operation can be performed automatically without requiring the operator to set the machining conditions for each machining operation.

Claims: A laser control system comprising: a laser oscillator (8) for performing laser machining by controlling an X-Y table with a numerical control system, characterised in that: a machining operation is designated by a G-code with a power output command (S), a pulse frequency command (P) and a pulse duty ratio (Q) for controlling the output of the laser oscillator (8). A system according to claim 1, wherein an assist gas control command is provided by a G-code. A system according to claim 1, comprising: an X-Y table; command means (1) for outputting a command program including a predetermined G-code, a power output command, a pulse frequency command and a pulse duty ratio; numerical control means (2) connected to the command means for receiving the command program, interpreting the command program and outputting the commands including the predetermined G-code, the power output command, the pulse frequency command and the pulse duty ratio command; servo amplifiers (3,4) connected to the numerical control means for receiving the commands from the numerical control means and outputting drive commands; servomotors (5,6) connected to the servo amplifiers for receiving the drive commands for driving the servomotor; a high frequency power source (7) connected to the numerical control system for outputting a predetermined power, frequency and duty ratio determined by the commands from the numerical control system; the oscillator being connected to the high frequency power source, an output of the laser being oscillated and amplified by the commands from the high frequency power source; and, valve means (10) connected to the numerical control means for providing assist gas, the commands from the numerical control system turning on and off the assist gas from the valves.

Inventors: ISOHATA SHIGERU, NAGAMINE TSUYOSHI, YAMAZAKI ETSUO, ISOHATA, SHIGERU, NAGAMINE, TSUYOSHI, YAMAZAKI, ETSUO
Applicants: FANUC LTD, FANUC LTD.
Application year: 1988
Main classification: B23K26
IPC codes: B23K26, H01S3, G05B19