Laser oscillator

Abstract

The present invention provides a laser oscillator that can suppress manufacturing costs and is more compact. A laser oscillator (1) outputs laser light, and comprises: a housing (10); a transformer (40) disposed in the housing (10) and connected to a power supply (2) to supply power to a first device (20) with a predetermined power consumption; and a power factor improvement unit (50) disposed in the housing (10) and having a power factor improvement circuit (53) for making the power factor close to 1. The power factor improvement unit (50) is connected to the power supply (2) to supply power to a second device (30) whose power consumption is relatively high compared to that of the first device (20).

Description

Technical Field

[0001] The present invention relates to a laser oscillator. Background Art

[0002] Laser processing machines that use lasers to process workpieces are known. The laser processing machine is equipped with a laser oscillator for generating the laser light that is irradiated onto the workpiece. Patent Document 1, for example, describes this technology. Patent Document 1 describes a laser oscillator comprising a light-emitting portion (resonant cavity unit) for providing excitation light and a power supply unit for supplying current to the resonant cavity unit to control the light emission of multiple light-emitting elements.

[0003] Laser oscillators are supplied with power supply voltages that vary from country to country, such as from distribution boards. For example, Japan uses 200V, Europe uses 400V, the United States uses 480V, and China uses 380V. To accommodate these power supply voltages, transformers are used to convert the voltage.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-103413 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] Transformers are built into laser oscillators or installed separately from them. However, increasing the laser output intensity requires installing many transformers, or the transformers become larger. Transformers are relatively inexpensive, but accommodating large or numerous transformers within a laser oscillator increases the size of the laser oscillator.

[0009] An object of the present invention is to provide a laser oscillator that can be further miniaturized while suppressing manufacturing costs.

[0010] Solutions for solving problems

[0011] One embodiment of the present disclosure relates to a laser oscillator that outputs laser light, the laser oscillator comprising: a housing; a transformer disposed within the housing and connected to a power supply to supply power to a first device having a specified power consumption; and a power factor improvement unit disposed within the housing and having a power factor improvement circuit for making a power factor close to 1, wherein the power factor improvement unit is connected to the power supply to supply power to a second device whose power consumption is relatively high compared to the power consumption of the first device.

[0012] Effects of the Invention

[0013] According to one embodiment, an object is to provide a laser oscillator that can be further miniaturized while suppressing manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a block diagram showing the electrical configuration of a laser oscillator according to one embodiment of the present invention.

[0015] Figure 2 This is a schematic diagram showing a power factor improvement unit of a laser oscillator according to one embodiment of the present invention.

[0016] Figure 3 This is a schematic diagram showing an example of a specific structure of a laser oscillator according to one embodiment of the present invention.

[0017] Description of Reference Numerals

[0018] 1: Laser oscillator; 2: Power supply; 10: Housing; 20: First device; 30: Second device; 40: Transformer; 50: Power factor improvement unit; 53: Power factor improvement circuit. DETAILED DESCRIPTION

[0019] Hereinafter, one embodiment of the present disclosure will be described with reference to the accompanying drawings. Figure 1 is a block diagram showing an electrical configuration of a laser oscillator 1 according to one embodiment. Figure 2 This is a schematic diagram showing a power factor improvement unit of a laser oscillator according to one embodiment.

[0020] like Figure 1 As shown, a laser oscillator 1 according to one embodiment includes a housing 10, a first device 20 having a predetermined power consumption, a second device 30 having a higher power consumption than the first device 20, a beam combiner 11, a laser processing head 12, a transformer 40, and a power factor improvement unit 50. The laser oscillator 1 operates using power supplied from a power supply 2, which is an AC power supply, via a distribution board 3, and emits laser light.

[0021] like Figure 1 As shown, the housing 10 accommodates a first device 20 , a second device 30 , a combiner 11 , a transformer 40 , and a power factor improvement unit 50 .

[0022] The first device 20 is a relatively low-power device among the devices constituting the laser oscillator 1. The laser oscillator 1 includes a dehumidifier 21 for performing a dehumidification operation, a control power supply 22, a safety circuit 23, a contactor coil 24, a 24V power supply unit 25, and a fan motor 26.

[0023] The second device 30 is a device that consumes relatively more power than the first device 20. The second device 30 is a device that primarily directly contributes to laser output and includes, for example, LD power supply units 31 and 32 (laser diode power supplies), laser resonant cavity units 33 and 34, laser diodes 33a and 34a included in the laser resonant cavity units 33 and 34, oscillation optical fibers 33b and 34b, and a transmission optical fiber 35.

[0024] Next, the respective structures of the second device 30 will be described.

[0025] The LD power supply units 31 and 32 include a switching circuit (not shown), a smoothing circuit (not shown), and a control circuit (not shown). The switching circuit includes a switching transistor and a diode. This switching circuit turns the switching transistor on and off according to a control signal from the control circuit, generating a charging current in conjunction with the diode. The smoothing circuit includes an inductor and a capacitor. Based on the charging current, this smoothing circuit generates a DC voltage across the capacitor and outputs this DC voltage to the laser resonator units 33 and 34.

[0026] The laser resonator unit 33 includes a laser diode 33a and an oscillation optical fiber 33b, and generates laser light in accordance with the voltage supplied from the LD power supply unit 31. The laser diode 33a serves as the laser light source of the laser oscillator 1. Specifically, when power is supplied from the LD power supply unit 31 to the laser diode 33a, the laser diode 33a causes excitation light to enter the oscillation optical fiber 33b.

[0027] The laser resonator unit 34 includes a laser diode 34a and an oscillation optical fiber 34b, and generates laser light in accordance with the voltage supplied from the LD power supply unit 32. The laser diode 34a serves as the laser light source of the laser oscillator 1. Specifically, when power is supplied from the LD power supply unit 32 to the laser diode 34a, the laser diode 34a causes excitation light to enter the oscillation optical fiber 34b.

[0028] The transmission optical fiber 35 is connected between each of the laser resonator units 33 and 34, the beam combiner 11, and the laser processing head 12 to transmit laser light. The excitation light oscillated by the laser resonator units 33 and 34 is transmitted to the beam combiner 11 through the transmission optical fiber 35.

[0029] The beam combiner 11 combines the laser beams generated in the laser resonator units 33 and 34 and inputs the combined beams to the laser processing head 12. The laser processing head 12 irradiates the workpiece with the laser beam.

[0030] Next, the transformer 40 will be described. The transformer 40 is connected to the power supply 2 of the distribution board 3. The transformer 40 steps up or steps down the AC voltage supplied from the power supply 2 and supplies it to the low-power first devices 20. Because the first devices 20, such as the dehumidifier 21 and the control power supply 22, have low power consumption, a compact transformer 40 can be used. Therefore, the transformer 40 is compact and can be accommodated within the housing 10.

[0031] Next, the power factor improvement unit 50 will be described. The power factor improvement unit 50 is connected to the power supply 2 via the distribution board 3. The power factor improvement unit 50 adjusts the AC voltage provided from the power supply 2 and provides power to the LD power supply units 31, 32 and the laser resonant cavity units 33, 34 as the second device 30. The power factor improvement unit 50 has a power factor improvement circuit 53 and is housed in the housing 10. The power factor improvement unit 50 involved in this embodiment is configured to support different power supply voltages in the range of AC380V to AC480V. In addition, with respect to the wiring method, the power factor improvement unit 50 can also be configured to support multiple wiring methods. For example, it can be switched from star wiring to delta wiring.

[0032] The power factor improvement unit 50 is a rectifier circuit that can input an AC voltage of a specific value and generate a DC voltage from the AC voltage internally and output the DC voltage. Figure 2 As shown, the power factor correction unit 50 includes a capacitor 52, a power factor correction circuit (PFC (Power Factor Correction)) 53, and six diodes 51. The power factor correction circuit 53 is a circuit that brings the power factor close to 1. The structure of the power factor correction unit 50 other than the power factor correction circuit 53 is a general rectifier circuit structure and is well known, so a detailed description is omitted here.

[0033] Next, a usage example of the laser oscillator 1 according to one embodiment will be described. Figure 3 This is a schematic diagram showing an example of a specific structure of the laser oscillator 1 according to this embodiment connected to the switchboard 3. Figure 3 In the figure, the control power supply 22 and the combiner 11 are omitted.

[0034] Power supply 2, serving as the power source for laser oscillator 1, is a three-phase AC power supply with a voltage of 380 to 480 volts AC. Power supply 2 is connected in a three-phase, three-wire, star-type configuration. Laser oscillator 1 is supplied with AC voltage by connecting three cables (U, V, and W phases) of power supply 2 via a distribution board 3. The AC voltage enters housing 10 from the U, V, and W phases, and is supplied to power factor improvement unit 50 as an input voltage of 380 to 480 volts AC via contactors and branch circuit breakers.

[0035] The power factor improvement unit 50 of the laser oscillator 1 includes two units: a first power factor improvement unit 50a and a second power factor improvement unit 50b. The first power factor improvement unit 50a is connected to the LD power supply unit 31 to adjust the power factor close to unity and to supply a DC voltage to the LD power supply unit 31. The second power factor improvement unit 50b is connected to the LD power supply unit 32 to adjust the power factor close to unity and to supply a DC voltage to the LD power supply unit 32.

[0036] The laser resonator unit 33 is supplied with a voltage of 380 V DC from the LD power supply unit 31, causing the laser diode 33a to generate laser light, and the excitation light is incident on the oscillation optical fiber 33b. The laser resonator unit 34 is supplied with a voltage of 380 V DC from the LD power supply unit 32, causing the laser diode 34a to generate laser light, and the excitation light is incident on the oscillation optical fiber 34b.

[0037] A single-phase AC voltage of 380V to 480V is supplied to the transformer 40 from two cables, the U-phase and V-phase cables of the power supply 2. The transformer 40 steps down the AC voltage from 380V to 480V to 200V AC. This voltage is then supplied to the dehumidifier 21, control power supply 22, safety circuit 23, contactor coil 24, 24V power supply unit 25, and fan motor 26 on the secondary side. In this embodiment, the input voltage of each first device 20 is 200V AC, and its specifications are standardized. This makes it easier to supply power to each first device 20 without using transformers 40 with different output voltages.

[0038] According to the laser oscillator 1 according to one embodiment of the present disclosure described above, the following effects can be achieved.

[0039] In a laser oscillator 1 according to one embodiment of the present disclosure, a transformer 40 and a power factor improvement unit 50 are housed in a housing 10. The transformer 40, which supplies power, and the power factor improvement unit 50 are used separately, depending on the power consumption of the electrical equipment of the laser oscillator 1. This can suppress increases in the overall manufacturing cost of the laser oscillator 1 and achieve miniaturization of the laser oscillator 1.

[0040] Specifically, when power is supplied to the second device 30 without using the power factor improvement unit 50, the power consumption of the second device 30 is high, and therefore the capacity of the electrical components of the laser oscillator 1, such as the power input unit, increases. In the laser oscillator 1 according to this embodiment, the power factor improvement unit 50 improves the power factor, thereby reducing the reactive current flowing to the LD power supply units 31 and 32. This allows efficient power to be supplied to the second device 30, which consumes high power, and reduces the overall size of the laser oscillator 1. Furthermore, since the power factor improvement unit 50 can be cooled, it can be more compact than the transformer 40. Furthermore, since heat generation can be suppressed, the power factor improvement unit 50 can be built into the laser oscillator 1, which has a simple structure, by being housed in the housing 10.

[0041] Furthermore, when the transformer 40 is used for the second device 30, which consumes high power, the amount of power supplied increases, necessitating a larger transformer 40 and increasing the amount of heat generated by the transformer 40. In the laser oscillator 1 according to this embodiment, the first device 20, powered by the transformer 40, consumes less power, allowing the transformer 40 to be smaller and suppressing heat generation. Furthermore, the transformer 40 is less expensive than the power factor improvement unit 50. Therefore, by using the transformer 40 and the power factor improvement unit 50 separately, depending on the power consumption of the electrical devices in the laser oscillator 1, the manufacturing cost of the laser oscillator 1 can be reduced.

[0042] Furthermore, the power factor improvement unit 50 of the laser oscillator 1 according to one embodiment of the present disclosure can support various power supply voltages and wiring methods, and the voltage specifications that can be input to the first device 20, which is powered by the transformer 40, are standardized. Thus, by simply selecting the transformer 40 that corresponds to the input voltage provided by the power supply 2, it is possible to accommodate different power supply voltages and wiring methods in different countries.

[0043] As mentioned above, although one embodiment related to this disclosure was described, this disclosure is not limited to the above embodiment, and appropriate changes can be made.

[0044] In the above embodiment, the first power factor improvement unit 50a and the second power factor improvement unit 50b are provided as separate units from the LD power supply units 31 and 32. However, they may be integrated into one unit. Specifically, the first power factor improvement unit 50a may be built into the LD power supply unit 31, and the second power factor improvement unit 50b may be built into the LD power supply unit 32.

[0045] In the above embodiment, the voltage specification that can be input to each first device 20 is standardized. However, the design of the voltage that can be input to the first device 20 is not particularly limited, and different voltages can be used.

Claims

1. A laser oscillator that outputs laser light to process a workpiece, the laser oscillator comprising: case; a transformer disposed in the housing and connected to a power source to supply power to a first device with a predetermined power consumption; and A power factor improvement unit is arranged in the housing and has a power factor improvement circuit that makes the power factor close to 1. The power factor improvement unit is connected to the power supply to supply power to a second device whose power consumption is relatively high compared to the power consumption of the first device.

2. The laser oscillator according to claim 1, wherein The first device is at least one of a dehumidifier, a control power supply, a safety circuit, a contactor coil, a 24V power supply unit, and a fan motor.

3. The laser oscillator according to claim 1 or 2, wherein: The second device is at least one of an oscillation optical fiber, a laser diode for injecting excitation light into the oscillation optical fiber, and a laser diode power supply for supplying power to the laser diode.

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