Abstract: Provided is a laser oscillator (2) including: a first electrode pair (7a); a second electrode pair (7b); a discharge power supply (4) that induces pulse discharge in the first and second electrode pairs (7a, 7b); and at least one of a discharge phase control unit (53) which extends control so that a first discharge phase (X1) to be attained in the first electrode pair (7a) and a second discharge phase (X2) to be attained in the second electrode pair (7b) will be different from each other during the pulse discharge induced by the discharge power supply (4), a duty cycle control unit (53) which extends control so that a first duty cycle (Y1) to be attained in the first electrode pair (7a) and a second duty cycle (Y2) to be attained in the second electrode pair (7b) will be different from each other during the pulse discharge, a pulse frequency control unit (53) which extends control so that a first pulse frequency (Z1) to be attained in the first electrode pair (7a) and a second pulse frequency (Z2) to be attai

Abstract: 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.

Abstract: A gas laser oscillator (10) provided with voltage detecting means (4a to 4d) for detecting the voltage of each of a plurality of discharge tube segments (6a to 6d) of a discharge tube before start of discharge and a discharge tube segment start judging means (1) for judging if each of the plurality of discharge tube segments (6a to 6d) has started based on the voltage of the discharge tube segments (6a to 6d) detected by the voltage detecting means (4a to 4d), wherein the discharge tube segment start judging means (1) allows all of the plurality of discharge tube segments (6a to 6d) to start only when the voltages of all of the discharge tube segments (6a to 6d) of the plurality of discharge tube segments are smaller than a predetermined voltage (Vb) is provided. Due to this, it is possible to judge an abnormality in the laser gas before the start of discharge without any work on the part of the operator and thereby prevent the discharge tube from being damaged.

Abstract: A laser apparatus (100) for performing the laser machining operation by condensing the laser light output from a laser oscillator (3) is disclosed. A laser output value calculation unit calculates a laser output value (L1) based on a command value (L0) issued to a laser oscillator (2). A temperature change estimating unit (31) estimates the temperature change or the temperature (Te) of specified component element(s) (7a, 7b) of the laser apparatus based on the elapsed time (t) and the laser output value calculated by the laser output value calculation unit. An adjusting unit (32) adjusts the conditions for controlling the laser or the conditions for laser machining based on the temperature change or the temperature of the specified component element estimated by the temperature change estimating unit. A stable laser machining operation is performed without a temperature sensor. The laser output value (L1) may be measured by a laser power sensor (5).

Abstract: A method of making a flanged tubular metallic part by cold forging is provided. The method comprises a step of forming an axial depression in a blank and a flange forming step of making the depression axially deeper while causing a metal of the blank to flow radially outward thereby forming the blank into an intermediate product having a flange. The flange forming step includes axially moving an inner punch of a die assembly so as to cause a leading end of the inner punch to be positioned more forward than a backward side surface of the flange thereby causing the intermediate product to be formed with a sleeve portion that is position backward of the flange while allowing an outer punch of the die assembly to apply a biasing force to a backward side surface of the flange during formation of the flange.

Abstract: 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 M2 for 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.

Abstract: 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 (alternative 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.

Abstract: A method of making a metallic shell for a spark plug is provided. The metallic shell includes a multi-stepped through hole, an intermediate tubular portion, a tip end side tubular portion and a base end side tubular portion. The through hole includes a large diameter hole section, an intermediate diameter hole section and a small diameter hole section. The method includes the steps of cutting a metal pipe that is used as a starting material to a predetermined length and thereby preparing a pipe-shaped blank, and subjecting the blank to a deformation process and thereby forming the blank into the metallic shell. A spark plug and a method of making the same are also provided.

Abstract: A method of making a flanged tubular metallic part by cold forging Is provided. The method comprises a step of forming an axial depression in a blank and a flange forming step of making the depression axially deeper while causing a metal of the blank to flow radially outward thereby forming the blank into an intermediate product having a flange. The flange forming step includes axially moving an inner punch of a die assembly so as to cause a leading end of the inner punch to be positioned more forward than a backward side surface of the flange thereby causing the intermediate product to be formed with a sleeve portion that is position backward of the flange while allowing an outer punch of the die assembly to apply a biasing force to a backward side surface of the flange during formation of the flange.

Abstract: 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. An ultraviolet ray contained in light emitted by electric discharge is utilized for exciting the photocatalyst.

Abstract: By heating a glass sealing material, a center electrode is sealed and fixed within an axial bore of an insulator. Formation of a groove in a head portion of the center electrode makes it possible to protect the head portion of the center electrode from deformation under a pressure which is applied upon filling the glass sealing material in a powder form in the axial bore. The glass sealing material is therefore assured to flow to a peripheral side wall of a flange portion of the center electrode, thereby enhancing mechanical engagement between the center electrode and the insulator, that is, uniting strength for them. A spark plug is hence obtained with improved impact resistance and accordingly, with sufficient durability.

Abstract: The present invention is intended to artificially break pit membranes in cell membranes of cells constituting wood and then to readily attain dryness of the wood. In view of the fact that one pit or the other pit of pits in the form of a pair is blocked with the torus 1 in felled wood to cause poor removal of water in cells, it is intended to prevent the blockage of the pit membrane, i.e., to break the pit membrane per se, thereby facilitating easy escapement of water in cells after the breaking. In the present invention, wood fuel is burned, and subject wood is allowed to stand in a treatment chamber filled with smoky wood gas generated by the combustion for a predetermined period of time, to expose the subject wood to far-infrared radiation and components contained in the wood gas.

Abstract: In a spark plug, a tubular insulator has an axial bore in which a center electrode and a terminal electrode are axially aligned, the terminal electrode having a seal portion fixedly supported by partly filling the axial bore with a glass sealant. The insulator further has a tapered shoulder portion between a diameter-reduced portion and a diameter-increased portion, each provided on the insulator. A metallic shell is placed around the diameter-increased portion of the insulator, a rear end of the metallic shell being caulked against the diameter-reduced portion of the insulator, a space between the metallic shell and the diameter-reduced portion of the insulator being filled with a ceramic powder. An inclination of the tapered shoulder portion of the insulator ranges from 10 to 45 degrees against a plane perpendicular to the terminal electrode. A roulette is formed on an outer surface of the seal portion of the terminal electrode in which the glass sealant is filled.

Abstract: A pair-facsimile device in which a pair of facsimile devices having similar performance characteristics are temporarily coupled to each other in a distributing channel starting from a manufacturer to a terailer shop, connected as, one compact integral product and in case of using the facsimile devices, they are separated and each of them is installed at a requisite location.

Abstract: In an outer electrode, a rear end of which is securely connected to a metallic shell of a spark plug by means of welding to form a spark gap between a front end of the outer electrode and a firing tip of a center electrode which is concentrically placed within the metallic shell through an insulator, a middle core which is provided which is made of copper, and the middle core is clad by a heat and spark-erosion resistant metal. A centermost core is clad by the middle core. The centermost core is made of a similar metal to the metallic shell, and rear end of the centermost core is welded to the metallic shell so as to reinforce a welding portion between the metallic shell and the outer electrode.

Abstract: A pair-facsimile device in which a pair of same kinds of facsimile devices are temporarily coupled to each other in a distributing channel starting from a manufacturer to a retailer shop, connected as one compact integral product and in case of using the facsimile devices, they are separated and each of them is installed at a requisite locations.

Abstract: A method of making terminal nut for ignition plug by plastic working, comprising; first step in which a metallic blank is struck at its end surfaces to flatten the end surfaces in prependicular to axial direction of the blank; second step in which a central conical dent is formed at one end surface of the blank, and forming first bottom-ended hole at other end surface of the blank; third step in which second bottom-ended hole is formed concentrically and continuously from the first bottom-ended hole at the blank to be diametrically lesser than the first bottom-ended hole; fourth step in which the blank is axially contracted to diametrically bulge outward by upsetting; fifth step in which a perforation hole is axially formed at the blank by punching in concentrical relationship with the first bottom-ended hole; sixth step in which the blank is shaved at its bulged portion.