JP2010212571A - Laser oscillation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser oscillation device that can be reduced in cost and maintain stable performance for a long period. <P>SOLUTION: The laser oscillation device includes one or more discharge tubes 4 constituting a flow path of laser gas, a gas circulation path 12 connected to the discharge tubes 4, and a plurality of blower means 10a, 10b and 10c provided in the gas circulation path 12, and parts of the gas circulation path 12 where the blower means 10a, 10b and 10c are provided are composed of a plurality of parallel paths, so that the laser gas is supplied from the plurality of blower means 10a, 10b and 10c to one discharge tube 4. With this constitution, the flow rate of the laser gas can be increased by increasing the number of the blower means 10a, 10b and 10c per each discharge tube 4, so that the laser oscillation device can have higher output inexpensively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention mainly relates to a laser oscillation device using a plurality of air blowing means.

  2. Description of the Related Art In recent years, laser processing machines are widely used for cutting and welding of various materials and shapes because of the feature that a workpiece can be processed in a non-contact manner and with little thermal influence. A conventional laser oscillation apparatus used for such a laser processing machine will be described below with reference to FIG.

  In the conventional laser oscillation device shown in FIG. 2, a laser gas 2 is circulated in a discharge tube 4 made of a dielectric. A high voltage power supply 8 connected to electrodes 6 and 7 provided around the discharge tube 4 generates a discharge 3 in the discharge tube 4. The laser gas 2 is excited by the discharge 3, passes through the total reflection mirror 14 and the partial reflection mirror 13, and is output as laser light 1 to the outside. Inside the gas circulation path 12 that forms a laser gas circulation path together with the discharge tube 4, the laser gas 2 is sent by the blowing means 10, and the heat exchanger 9 is used to lower the temperature of the laser gas raised by the discharge 3 and the blowing means 10. 11 are arranged.

  Next, the structure and operation of the blowing means 10 will be described. The air blowing means 10 includes a gas circulation air blowing section provided in the gas circulation path 12 and a driving section adjacent thereto, and the air blowing section and the driving section are connected to each other by a shaft. The blower is connected to the gas circulation path 12 and allows laser gas to flow through a gas blower such as a rotor blade. On the other hand, the drive unit is configured to transmit power to the blower unit by rotation of drive means such as a motor. In general, an inverter (frequency conversion device) or the like is often used as a method for supplying electric power to the drive unit of the air blowing means 10, and a three-phase power source is controlled by the inverter unit 24 for power control and frequency conversion control. The rotational speed of the means 10 can be controlled.

  As shown in FIG. 2, acceleration time and deceleration time are set in the soft start unit 22, and the ratio of the output voltage to the frequency is set in the V / F setting unit 23, and an operation start signal of the control device 21 is set. In accordance with the acceleration time of the soft start unit 22 and the setting condition of the relationship between the frequency and the output voltage set in the V / F setting unit 23, the inverter unit 24 is controlled to start the operation of the blower unit 10 until the set frequency. After acceleration, the vehicle is operated at a constant frequency (number of rotations). Further, in response to the operation stop command of the control device 21, the operation is decelerated and stopped according to the relationship between the deceleration time of the soft start unit 22, the frequency set in the V / F setting unit 23, and the output voltage, contrary to the startup. .

  In general, the relationship between the frequency of the V / F setting unit 23 and the output voltage is set such that the output voltage is set low during the low frequency immediately after startup in order to suppress the startup inrush current at the start of the operation of the blower 10. The frequency is gradually increased with the lapse of time, and the output voltage is increased as the frequency is increased, so that the rotational speed of the blower 10 can be smoothly increased (see, for example, Patent Document 1). .

Such a conventional laser oscillation apparatus needs to improve the capability of the blowing means 10 in order to increase the circulating flow rate of the laser gas as means for increasing the output.
JP 2003-110172 A

  As described above, it is common to increase the output of the laser oscillation device by improving the air blowing capability of the air blowing means 10 used for the laser gas circulation of the laser oscillation device and increasing the circulation flow rate of the laser gas. is there.

  In order to improve the capacity of the air blowing means, there is a means for efficiently blowing air with an inverter or the like. However, since the basic air blowing capacity depends on the performance of the air blowing means 10, a turbo as the air blowing means is required to increase the output beyond a certain level. It was common to use a pump.

  However, when a turbo pump is used, there is a problem that the cost increases.

  An object of the present invention is to provide a laser oscillation device that can reduce the cost of the device and maintain stable performance over a long period of time.

  In order to achieve the above object, the present invention comprises one or more discharge tubes constituting a laser gas flow path, a gas circulation path connected to the discharge tube, and a plurality of blowing means provided in the gas circulation path. A portion of the gas circulation path provided with the blowing means is constituted by a plurality of parallel paths, and the laser gas from the plurality of blowing means is supplied to the one discharge tube.

  With this configuration, the flow rate of the laser gas can be increased by increasing the number of blowing means per discharge tube, and the output of the laser oscillation device can be increased at low cost.

  As described above, the present invention can increase the flow rate of laser gas by using a plurality of general air blowing means, and not only can reduce the cost of the apparatus, but also can maintain stable performance over a long period of time. A laser oscillator device that can be provided can be provided.

(Embodiment)
Hereinafter, a laser oscillation apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a laser oscillation apparatus according to the present embodiment.

  In addition, the same code | symbol is attached | subjected to the same part as the conventional structure.

  In the laser oscillation device shown in FIG. 1, a laser gas 2 is circulated in a discharge tube 4 made of a dielectric. A high voltage power supply 8 connected to electrodes 6 and 7 provided around the discharge tube 4 generates a discharge 3 in the discharge tube 4. The laser gas 2 is excited by the discharge 3, passes through the total reflection mirror 14 and the partial reflection mirror 13, and is output as laser light 1 to the outside. Inside the gas circulation path 12 that forms a laser gas circulation path together with the discharge tube 4, the laser gas 2 is sent by the blowing means 10a, 10b, 10c, and the temperature of the laser gas raised by the discharge 3 and the blowing means 10a, 10b, 10c. In order to lower the temperature, heat exchangers 9 and 11 are arranged.

  A gas cylinder 31 for supplying laser gas is connected to the gas circulation path 12 through a solenoid valve in the middle of the gas circulation path 12.

  Further, a vacuum pump 36 is connected to the gas circulation path 12 in order to discharge the laser gas deteriorated by the discharge from the gas circulation path 12, and the vacuum pump is controlled by the control device 21.

  Then, the gas pressure in the gas circulation path 12 is detected by the gas pressure sensor 32 and a signal from the gas pressure sensor 32 is input to the control device 21 to control the amount of laser gas supplied from the gas cylinder 31 by the electromagnetic valve, and the vacuum. The pump 36 controls the discharge of the laser gas to balance the pressure.

  Next, the structure and operation of the blowing means 10a, 10b, 10c will be described. The air blowing means 10a, 10b, and 10c are composed of a gas circulation air blowing portion provided in the gas circulation path 12 and a driving portion adjacent thereto, and the air blowing portion and the driving portion are connected to each other by a shaft. It has become. The blower is connected to the gas circulation path 12 and allows laser gas to flow through a gas blower such as a rotor blade. On the other hand, the drive unit is configured to transmit power to the blower unit by rotation of drive means such as a motor. In general, an inverter (frequency converter) or the like is often used as a method for supplying power to the driving units of the blowing units 10a, 10b, and 10c, and the inverter unit 24 performs power control and frequency conversion control on the three-phase power source. Thus, the rotational speed of the air blowing means 10a, 10b, 10c can be controlled.

  As shown in FIG. 1, acceleration time and deceleration time are set in the soft start unit 22, and the ratio of the output voltage to the frequency is set in the V / F setting unit 23, and an operation start signal of the control device 21 is set. In accordance with the acceleration time of the soft start unit 22 and the setting condition of the relationship between the frequency and the output voltage set in the V / F setting unit 23, the inverter unit 24 is controlled to start operation of the blowing means 10a, 10b, 10c, After accelerating to the set frequency, the motor is operated at a constant frequency (rotation speed). Further, in response to the operation stop command of the control device 21, the operation is decelerated and stopped according to the relationship between the deceleration time of the soft start unit 22, the frequency set in the V / F setting unit 23, and the output voltage, contrary to the startup. .

  In general, the relationship between the frequency of the V / F setting unit 23 and the output voltage is such that the output voltage is lowered while the frequency is low immediately after startup in order to suppress the startup inrush current at the start of operation of the air blowing means 10a, 10b, 10c. The frequency is gradually increased with the passage of time, and the output voltage is increased with the increase of the frequency so that the blowing means 10a, 10b, 10c can rise smoothly. .

  The above configuration is the same as that of the conventional laser oscillation device, but the feature of the present embodiment is that the portion of the gas circulation path 12 provided with the air blowing means 10a, 10b, 10c is connected to a plurality of parallel paths (air blowing means). 10a, the path of the blower means 10b, and the path of the blower means 10c), and the laser gas is supplied from the plurality of blower means 10a, 10b, 10c to one discharge tube 4. .

  The air blowing means 10a, 10b, and 10c are connected to gas discharge paths for discharging the laser gas from their drive units, gas pressure sensors 33 are provided in these gas discharge paths, and oil from the drive units is provided. Each gas discharge path is connected by a manifold 35 via an oil trap 34 for collecting mistakes, and the manifold 35 is discharged by a vacuum pump 36.

  The signals of these gas pressure sensors 33 are input to the control device 21 so as to drive the air blowing means 10a, 10b, 10c and drive control of the vacuum pump 36.

  In this configuration, the pipe diameters of the gas discharge paths from the air blowing means 10a, 10b, and 10c are all the same, and the pipe lengths from the air blowing means 10a, 10b, and 10c to the gas pressure sensor 33 are the same. It has a configuration.

  Therefore, it is possible to measure the pressure fluctuations of the driving units of the plurality of blowing units 10a, 10b, and 10c without variation, and by operating the blowing units 10a, 10b, and 10c at the same operation rate, a highly efficient and stable laser gas can be measured. Circulation can be performed.

  According to the above configuration, the portion of the gas circulation path 12 provided with the blowing means 10a, 10b, and 10c is configured by a plurality of parallel paths (the path of the blowing means 10a, the path of the blowing means 10b, and the path of the blowing means 10c). In addition, since the laser gas is supplied from the plurality of air blowing means 10a, 10b, and 10c to one discharge tube 4, the discharge tube is formed using a conventional inexpensive, for example, gear type compression pump type air blowing means. By increasing the number of blowing means per one, the flow rate of the laser gas can be increased, the output of the laser oscillation device can be increased at a low cost, and the piping of the gas discharge path from the drive part of each blowing means Since all the diameters are the same and the pipe length from the air blowing means 10a, 10b, 10c to the gas pressure sensor 33 is the same, even if the number of air blowing means is increased, each air blower accurately It can be controlled.

  The laser oscillation device of the present invention is useful as a laser oscillation device that can achieve high output at low cost.

Schematic configuration diagram of a laser oscillation device in an embodiment of the present invention Schematic configuration diagram of a conventional laser oscillation device

DESCRIPTION OF SYMBOLS 1 Laser beam 2 Laser gas 3 Discharge 4 Discharge tube 6 Anode electrode 7 Cathode electrode 8 High voltage power supply 9 Heat exchanger 10a, 10b, 10c Blower means 11 Heat exchanger 12 Gas circulation pipe 13 Partial reflection mirror 14 Total reflection mirror 21 Control Device 22 Soft start section 23 V / F setting section 24 Inverter section 31 Gas cylinder 32, 33 Gas pressure sensor 34 Oil trap 35 Manifold 36 Vacuum pump

Claims (4)

One or more discharge tubes constituting a laser gas flow path, a gas circulation path connected to the discharge tube, and a plurality of blowing means provided in the gas circulation path, the gas circulation provided with the blowing means A laser oscillation apparatus, wherein a path portion is configured by a plurality of parallel paths, and laser gases from the plurality of blowing means are supplied to the one discharge tube. The air blowing means includes a gas circulation air blowing section provided in the gas circulation path and a driving section adjacent thereto, and a gas discharge path for discharging laser gas from the driving section is provided. 2. The laser oscillation device according to claim 1, wherein the pressure loss in the gas discharge path is the same. The laser oscillation device according to claim 2, wherein the pipe diameters of the gas discharge paths of the plurality of air blowing means are the same. The laser oscillation device according to claim 2 or 3, wherein the piping lengths of the gas discharge paths of the plurality of blowing means are the same.

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