Fanuc Corporation

Akira Egawa

Michinori Maeda

Minoru Ando

Norio Karube

Mitsuo Manabe

Etsuo Yamazaki

Nobuaki Iehisa

Kazuhiro Suzuki

Yoshitaka Kubo

Kazuya Ohta

Eiji Kobayashi

Hajime Ikemoto

Atsushi Mori

Akihiko Nishio

Hiroaki Tokito

Takafumi Murakami

Takeshi Watanabe

Toshiyasu Shiomi

Akira Miyake

Motohiko Sato

Kazuhiro Room12-602 Fanuc Suzuki

Motohiko Fanuc Dai2virakaramatsu Sato

Yoshitaka Room 12-503 Fanuc Manshonharimomi Kubo

Kazuhiro Room12-602 Fanuc Manshonharimomi Suzuki

A gas laser apparatus including a laser oscillating section including a blower forcibly circulating a medium gas in a medium circuit, and a blower monitoring section monitoring a maintenance state of the blower. The blower includes a lubricant storage chamber storing a lubricant, and a lubricant monitoring chamber connected to the lubricant storage chamber to ensure fluidic communication therebetween at a position lower than an oil level of a lubricant having a predetermined appropriate volume and stored in the lubricant storage chamber. The blower monitoring section includes a lubricant detecting section detecting that a lubricant stored in the lubricant storage chamber of the blower flows into the lubricant monitoring chamber and at least a part of the lubricant is present in the lubricant monitoring chamber, as a result of internal-pressure change in the lubricant storage chamber, and a lubricant-change judging section monitoring whether the lubricant detecting section detects a presence of the lubricant in the lubricant monitoring chamber, before the laser oscillating section is activated, and judging that, when the lubricant detecting section does not detect the presence, the lubricant stored in the lubricant storage chamber is in a state immediately after a lubricant change.

Gas laser apparatus, and method and device for monitoring blower

A gas laser oscillating unit having a gas junction part where gas flow may be stable, whereby a stable laser beam output and/or a laser beam that does not fluctuate very much may be achieved. The laser gas, flowing through first and second excitation parts, is introduced into the first and second tapered gas flow passages. After that, the two gas flows are mixed at or near the center point of a gas junction part and the mixed gas flows in a next flow passage. Then, one of the gas flows from the first excitation part is biased toward the &#x2212;X direction by a first biasing member arranged in the first gas flow passage, and the other gas flow from the second excitation part is biased toward the +X direction by a second biasing member arranged in the second gas flow passage.

Gas laser oscillating unit

A discharge excitation type gas laser oscillator has a discharge excitation unit for exciting a laser gas by discharge in a discharge tube to generate induced emission of laser light, a high-frequency power supply unit for supplying power to the discharge tube, and a controller unit for controlling output current of the high-frequency power supply unit. The laser oscillator further has an output detecting section that detects actual current value of the high-frequency power supply unit supplying power to the discharge tube at an arbitrary pressure lower than the high pressure during the steady-state operation, at the start of the laser oscillator, after the laser gas begins discharge excitation at a pressure lower than the high pressure during steady-state operation, an output comparison section that compares the detected actual current value with a normal current value that has been detected when the gas composition of the laser gas is normal at the same pressure as the actual current value is detected; and a power supply control section that discriminates, if the difference between the actual current value and the normal current value is equal to or greater than a preset value, that the gas composition of the laser gas is abnormal, and stops output of the high-frequency power supply unit.

Method for discriminating anomaly in gas composition and discharge excitation type gas laser oscillator

A laser-machining device () for machining a workpiece (W) by radiating it with the laser beam output from a nozzle () of a laser oscillator () is disclosed. A gap amount sensor () detects the gap amount between the workpiece and the nozzle. An approach unit () causes the nozzle to approach the workpiece to a position suitable for the laser machining. The approach unit performs a first approach operation () for making the nozzle approach the workpiece using the gap amount detected by the gap amount sensor until the gap amount comes to assume a predetermined value, and a second approach operation (), after the first approach operation, for causing the nozzle to approach the workpiece until the complete approach without using the gap amount detected by the gap amount sensor. As a result, the required time is shorter and a stable piercing process can be executed.

Laser-machining device

A gas laser oscillator includes a supply-side valve for regulating a laser gas supply to a gas chamber, an exhaust-side valve for regulating a laser gas exhaust from the gas chamber, a gas pressure measuring device for measuring a pressure in the gas chamber, and a control device functioning as a laser gas replacement measuring device. The control device makes a first measurement and a second measurement of the pressure in the gas chamber by a gas pressure measuring device at a predetermined time interval during the vacuuming or purging of the gas chamber, and determines the laser gas replacement amount per unit time during the laser oscillating operation, based on the results of the first and second measurements.

Gas laser oscillator and method of measuring laser gas replacement amount

A high-frequency discharge excited gas laser oscillator receiving power from a laser power supply controlled by a pulse command, the high-frequency discharge excited gas laser oscillator provided with a power detecting section for detecting supply power from the laser power supply to a discharge tube and a pulse command control section positioned at an upstream side of the laser power supply, comparing an allowable upper limit value of supply power found from a relationship between a discharge tube temperature and supply power and an actual supply power detected by the power detecting section, stopping the pulse command value to the discharge tube when the supply power is higher than the allowable upper limit value, and setting a pulse command value based on the allowable upper limit value.

High frequency discharge excited gas laser oscillator

A laser processing system including a laser processing machine capable of operating along an inherent control axis, an axis driving section driving the control axis of the laser processing machine, a laser oscillator supplying a laser beam to the laser processing machine, a control unit controlling the axis driving section and the laser oscillator, and a transfer line connecting the axis driving section and the laser oscillator to the control unit in a daisy-chain mode. The control unit includes a data preparing section preparing, from a given laser processing program, motion data commanded to the axis driving section and laser output-condition data commanded to the laser oscillator; a data converting section converting the motion data and the laser output-condition data, prepared by the data preparing section, into serial data including the motion data and the laser output-condition data described in a time-series fashion, based on a communication data format common to the axis driving section and the laser oscillator; and a data transmitting section transmitting the serial data, obtained by the data converting section, to the transfer line at a predetermined command cycle common to the motion data and the laser output-condition data included in the serial data.

Laser processing system

A laser cutting apparatus capable of properly cutting a workpiece having a large thickness with a laser beam. The laser cutting apparatus includes a gas laser oscillator; and an optical system including a collective lens and transmitting and collecting a laser beam generated in the gas laser oscillator to irradiate a workpiece with the laser beam. An index Mfor evaluating a beam quality of the laser beam emerging from the optical system, with which the workpiece is irradiated, is in a range of 2.8 to 4.5; while the index Mis defined by a formula: M=&#x3c0;&#xd7;(dm)/(4&#xd7;&#x3bb;&#xd7;Zr); in which &#x3bb; is a wavelength of the laser beam; dm is a minimum beam diameter of the laser beam in a predetermined optical-path range including a focal point of the collective lens; and Zr is a distance between a first position on an optical axis, at which the minimum beam diameter dm is established, and a second position on the optical axis, at which a beam diameter '2&#xd7;dm' is established, in the laser beam in the predetermined optical-path range.

Laser cutting apparatus with a high quality laser beam

In an laser oscillator (), a blower () for circulating a laser medium between an electric discharge tube () and a circulating passage () includes: a casing () having a suction port () and an exhaust port (); and a blade () pivotally supported in the casing () so that the blade () can face the suction port () and the exhaust port (). The blade () is formed into a shape in which a diameter of the blade () is different at a position on a cross section perpendicular to a rotary central line (O), and a gap (G) between a portion, in which a diameter of the blade () is relatively large, and the casing is larger than a gap (G) between a portion, in which a diameter of the blade () is relatively small, and the casing. Due to the foregoing, a highly reliable blower used for a laser oscillator, the reduction of the blower efficiency of which is suppressed to be as small as possible, can be provided.

Blower used for laser oscillator

A plurality of discharge sections are formed in an optical resonance space and are provided with electrodes that are mutually different in for example shape, size and construction. Laser medium gas flows through a circulatory passage passing through a fan and heat exchangers. Mutually different modes can be obtained when discharge is produced independently in the discharge sections. When discharge is produced in both of the discharge sections, the various intermediate modes can be obtained, in accordance with the distribution of power supplied from power sources for discharge excitation that are independently operated. If the number of discharge sections is three or more, it is possible to control the distribution of the discharge power that is supplied to the discharge sections in regard to at least two discharge sections of these discharge sections, and the shape and dimensions of the discharge sections or shape, dimensions and construction of the electrodes are selected such that 'different modes are excited when independently discharged'.

Gas laser oscillation device

A gas laser oscillator of easy maintenance which is capable of switching a beam mode at high speed. Electric discharge sections in which gas medium is flown are formed in an optical resonating space in an electric discharge tube between a rear mirror and an output mirror. Electrodes are connected to electric discharge power sources (alternating current or direct current power sources). Coils are wound around the electric discharge tube at the respective electric discharge sections and excited by coil excitation circuits. Directions and intensities of the excitation currents from the coil excitation circuits are controlled by a controller. Regions in which the electric discharge currents flow between the electrodes in the respective electric discharge sections are varied by magnetic fields generated by the coils in accordance with the directions and intensities of the excitation currents of the coils, to thereby control the beam mode.

Gas laser oscillator

A laser oscillator capable of preventing contamination of optical components by organic matter such as oil mist. Gas laser medium in an optical resonator constituted by optical components is pumped by an electric discharge generated in an electric discharge tube to produce a laser beam. The gas medium flows at high speed in the electric discharge tube incorporated in a circulating path including a blower. A part of lubrication oil of the blower is evaporated and mixed into the gas medium. Since the optical components are cooled by retaining mechanisms to prevent temperature rise of the components and a gas stagnation occurs between the optical component and the electric discharge tube, the evaporated oil mist tends to be congealed and adhered to a surface of the optical component. A photocatalyst arranged in the vicinity of the optical component effectively decomposes and removes the oil mist.

Laser oscillator

A laser oscillator capable of effectively collecting and removing particulate foreign matter contained in gas laser medium flowing in a circulating path. An electric discharge section arranged in an optical resonator is incorporated into a circulating path of the gas medium including a heat exchanger and a blower. The gas laser medium flows at a high speed in the circulating path. At least one spiral-flow dust collecting mechanism is provided in the circular path downstream of the heat exchanger, and the gas laser medium discharged from the blower is supplied to the electric discharge section through the spiral-flow dust collecting mechanism. The gas laser medium containing the particulate foreign matter spirally flows around an inner pipe in a cylindrical body of the spiral-flow dust collecting mechanism. While spirally flowing in the cylindrical body, the foreign matter having a relative density larger than that of the gas medium is separated from the gas medium by centrifugal force, to introduced into a dust collecting section through a slit to be deposited. Pressure of the gas laser medium flowing in the circulating path may be adjusted in accordance with diameter and/or mass of the particulate foreign matter to be removed.

A laser oscillator which is capable of preventing damage caused by light reflected from a workpiece and a decrease in productivity resulting therefrom. Between a rear mirror and an output mirror within the laser oscillator is arranged a bending mirror. The bending mirror has a coating formed on the surface thereof, which reflects S-polarized light sufficiently but has a low reflectance with respect to P-polarized light. A laser beam is amplified between the rear mirror and the output mirror, and emitted through the output mirror. The laser beam output at this time is formed by S-polarized light. The S-polarized light is converted to a circularly polarized light by a zero-shifting mirror and a quarter wavelength mirror. The laser beam converted to the circularly-polarized light turns in a perpendicular direction at a mirror and is converged onto a workpiece by a condenser lens. Part of the laser beam irradiated onto the workpiece is reflected therefrom and returns along the same path that the emitted laser beam travelled. This reflected light input via the output mirror is formed by P-polarized light. The P-polarized light received back into the laser oscillator is attenuated when reflected from the bending mirror.

An external optical system is simplified in construction so that a laser oscillation apparatus is low-priced and compact as a whole. On the side of one end portion (10A) of a return-type resonator (10), a laser beam is reflected by a polarizing mirror (147) to be incident upon a polarizing mirror (146) which is situated diagonally below the mirror (147), and is also reflected by a polarizing mirror (142) to be incident upon a polarizing mirror (141) which is situated diagonally above the mirror (142). Thus, at the one end portion (10A), the polarizing mirror (141) and the like are arranged so that optical axes cross each other. Since the emitted laser beam forms a linear polarized beam inclined at an angle of 45.degree. to a horizontal plane, as indicated by arrow (100), the laser beam can be subjected to circular polarization by using only one 1/4-wavelength mirror. Thus, the construction of the external optical system can be simplified. Since the optical axes cross each other at the return side, moreover, the construction can be made compact as a whole.

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Gotenba, Japan

Akira Egawa