Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Denki K.k.

Shuji Ogawa

Shigenori Yagi

Masaki Kuzumoto

Norikazu Tabata

Satoru Kotoh

Kunihiko Kaga

Masaru Kanaoka

Koji Yasui

Takashi Yumura

Masaaki Tanaka

Tetsu Yamamoto

Miki Kurosawa

Akihiro Otani

Masayuki Sugahara

Takanori Ueno

Kiyoshi Funai

Atsuhiko Kawamura

Toru Murai

A machining head of a laser machining apparatus comprises a main assist gas nozzle at the center portion of the machining head for supplying a main assist gas and one or more annular sub assist gas nozzles surrounding the main assist gas nozzle, whose jet outlet of the innermost diameter is larger or equal to the jet outlet of main assist gas. The jet outlet of the main assist gas nozzle is positioned at upstream of said jet outlets of the respective sub assist gas nozzle. According to the above construction, the jet gas pressure and the jet gas velocity vary continuously at the assist gas jet outlet and the jet gas pressure and flow velocity fluctuation of the main assist gas are increased.

Machining head and laser machining apparatus

A machining head of a laser machining apparatus for adjusting flow speed distribution includes a sub assist gas supply inlet; an annular partition for partitioning the inside of the sub assist gas nozzle toward axis direction; an annular flat board which contacts rotatably to the side surface of the down stream of the annular partition wall, and interrupts a part of gas supply inlet, and a part of which is notched; two partition plates which are mounted on both end portions of the annular flat board, partition the inside of the sub assist gas nozzle down stream of the annular partition wall, and rotate with the annular flat board; a driving device for driving the annular flat board; and a control apparatus for operating the driving device.

A method and apparatus for detecting the machining status of a laser beam machining device, having a multi-mirror resonator for generating a machining beam, which utilizes the secondary light generated by the machining operation and returned from the workpiece surface into the resonator for control of the machining operation. The oscillator and accompanying components, such as beam dividing mirrors and splitters, are operative to separate the secondary light from the laser beam within the resonator and direct the two beams separately to detectors located outside of the resonator. Alternatively, the secondary light and laser beam may be directed to the outside together where they are separated by an integrating sphere for detection.

Laser machining apparatus and method

A laser oscillator includes a housing which seals a laser medium gas from the atmosphere, concave mirrors (or a set of concave and convex mirrors) positioned in the housing and having the laser medium gas therebetween, an apertured mirror positioned between the concave mirror and the other concave or convex mirror on a line connecting the spherical centers of the mirrors at a predetermined angle relative to the line, and a window through which a laser beam reflected by the apertured mirror is output from the housing. The apertured mirror has a curved reflective surface, thereby simplifying the optical system in the housing and increasing the system's reliability.

Laser oscillator having a curved mirror with a through-hole

A laser cutting head has a nozzle as well as a lens disposed in a holder that is moveable by a mechanical drive along the laser beam axis and has a working gas supply port at the nozzle side of the head. The head also has an annular groove that is defined by concentric internal and external cylinders and a drive gas supply port in the external cylinder at the laser supply side of the head. An annular piston is formed at the laser beam application side end of the movable lens holder, that is disposed in the annular groove. The piston may be pressed toward the nozzle side of the head by the pressure of drive gas supplied through the drive gas supply port. The drive gas pressure and the area of the piston is selected to define an offsetting pressure for reducing the effect of the cutting gas on the lens and lens holder.

Laser processing head and method for operation thereof

A laser oscillator having an enclosure serving as a vacuum vessel which is capable of preventing an electric discharge from occurring between a pair of electrodes and the inner surface of the vacuum vessel. The laser oscillator is made smaller in size, lower in total weight, and lower in manufacturing cost while securing a sufficient insulation gap between the electrodes and the inner surface of the vacuum vessel.

Laser oscillator

A laser device having an infrared laser medium and an aperture member disposed within a resonator in which the mode symmetry is improved. An optical resonator including a total reflecting mirror and a partial reflecting mirror disposed at opposite ends of a gap between electrodes is arranged parallel to an optical axis and orthogonal to a gas flow direction. An aperture member disposed along the optical axis between the mirrors on the side of the partial reflecting mirror has the form of a ring having an axis coinciding with the optical axis. Plural laser beam detecting elements are disposed on the inner peripheral area of the ring. The angular positions of the mirrors are controlled such that a difference in outputs of the detecting elements is minimized.

Laser device

A gas laser device comprises a discharge tube made of a dielectric material; a laser medium gas which is circulated at a high speed within the discharge tube in the axial direction of the discharge tube; an optical resonator composed of a total refelection mirror and a partial reflection mirror, both being disposed in mutual confrontation at both ends of the discharge tube; a plurality of electrodes oppositely provided on the outer periphery of the discharge tube; and a power source for applying an a.c. voltage to the oppositely provided electrodes to generate silent discharge.

Gas laser device

A silent discharge type pulse laser device having a pair of opposing electrodes, at least one of which is an electrode covered by a dielectric, which is mounted opposite to a metallic electrode with a silent discharge space in between, a laser resonator consisting of a total reflection mirror and a partial reflection mirror mounted opposite to each other with the silent discharge section in between, a source of high frequency voltage for supplying to the pair of electrodes a high frequency voltage having a predetermined period for silent discharge, and a controller for controlling the high frequency voltage from the source with respect to a first interval and a second interval that form a period longer than the period for silent discharge. The high frequency voltage is supplied to the silent discharge section at a first peak voltage value during the first interval and at a second peak voltage value during the second interval, wherein the second peak voltage value is sufficient to cause a discharge but insufficient to excite laser oscillation.

Silent discharge type pulse laser device

A silent discharge-type laser device in which silent discharge is established to produce a laser output by applying a high-frequency voltage across a set of opposing electrodes, at least one of the electrodes being a dielectric electrode; signals which are fed to the power source which produces a high-frequency voltage, used to modify the amplitude of the high-frequency output or to modify the frequency of the high-frequency output. According, the output voltage produced by the high-frequency power source can be increased or decreased at high speeds.

Silent discharge-type laser device

A silent discharge gas laser apparatus has three or more electrodes arranged in axial symmetry with the laser radiation axis and supplied with voltage from a multi-phase high frequency power source to establish a continuous discharge and a higher discharge density at reduced frequencies, particularly in the central region of the discharge zone.

Multi-phase silent discharge gas laser apparatus

A silent discharge gas laser comprises an earthing electrode and a high voltage electrode whose discharge surface is covered with a dielectric and a power source for applying an AC high frequency high voltage to excit a laser gas. The power source periodically and intermittently applies high frequency voltage to turn on and off to give high peak value.

Silent discharge gas laser

A silent discharge type gas laser device comprises a high voltage side electrode and a low voltage side electrode which are disposed through a discharge space wherein substantial surface area of at least one of the electrodes is covered with a dielectric and an equivalent diameter of the covered dielectric is less than several times the length of the discharge space.

Growing community of inventors

Aichi, Japan

Shuji Ogawa