Abstract: An on-demand-type drive state control apparatus for a vehicle is provided. In the case where acceleration slippage occurs at drive wheels (rear wheels) of a vehicle when a drive system is in a two-wheel drive state, the drive system is switched from the two-wheel drive state to a four-wheel drive state. That is, the maximum transmittable torque of a multi-disc clutch mechanism increases from “0” to a predetermined value. In the four-wheel drive state, the maximum transmittable torque decreases stepwise from the present value by a predetermined value every time the vehicle travels over a predetermined distance in a state in which none of the wheels cause acceleration slippages. That is the clutch drive current supplied to the multi-disc clutch mechanism decreases gradually (stepwise or in a plurality of steps), and the drive torque distributed to the front wheels (rear wheels) decreases (increases) gradually.

Abstract: A spark plug (100) including a center electrode (130) and a ground electrode (140), which is formed by joining a ground electrode chip (143) to a ground electrode base material (141) via an intermediate member (142). A method for producing the spark plug (100) includes providing a projecting portion (142p) on the intermediate member (142), and projection-welding the intermediate member (142) to the ground electrode base material (141) by means of the projecting portion (142p), to thereby join the intermediate member 142 to the ground electrode base material (141). Further, the intermediate member (142) of the spark plug (100) includes a cylindrical columnar portion (142e) which is joined to the ground electrode chip (143), and a flange portion (142d) which is joined to the ground electrode base material (141) and which flange portion (142d) has a diameter greater than that of the cylindrical columnar portion (142e).

Abstract: A drive state control apparatus is applied to a vehicle which has not only a transfer including a multi-disc clutch mechanism but also a changeover mechanism interposed in an axle and which can be switched between 2WD and 4WD. When a 2WD-to-4WD changeover condition is satisfied, the multi-disc clutch is immediately switched from a “decoupled state” to a “coupled state.” Meanwhile, a connecting operation of the changeover mechanism is started upon establishment of a state in which left and right rear wheels have no acceleration slippage, and a state in which rotational speeds of first and second axles on opposite sides of the changeover mechanism are approximately equal to each other. In addition, in the case where the left and right rear wheels have acceleration slippage after the 2WD-to-4WD changeover condition has been satisfied, an E/G output reduction control is executed. Thus, the connecting operation can be performed smoothly.

Abstract: A spark plug having an electrode, an insulator, a metallic shell, a main ground electrode, and at least two auxiliary ground electrodes.

Abstract: Provided are a spark plug in which the occurrence of spark blowout or the like is restrained for improvement of ignition performance, and a method of manufacturing the spark plug. A ground electrode 27 of the spark plug has a protrusion 28 which faces a center electrode 5. The distal end surface of the protrusion 28 has a noble metal tip 32 provided at the center thereof and includes an annular fusion portion 33 adjacent to the periphery of the noble metal tip 32, and an annular electrode base metal surface located externally of the annular fusion portion 33. A spark discharge gap 35 is formed between the center electrode 5 and the distal end of the protrusion 28 including the noble metal tip 32.

Abstract: A voltage nonlinear resistor is made of a sintered body that mainly includes zinc oxide grains, spinel grains including zinc and antimony as main ingredients, and a bismuth oxide phase, in which the bismuth oxide phase includes at least one of alkali metals selected from the group of potassium and sodium at a ratio in the range of 0.036 at % or higher and 0.176 at % or lower. The voltage nonlinear resistor has good voltage nonlinearity and loading service life characteristics, and can be used for a lightning arrester.

Abstract: A spark plug in which the center electrode is formed by laser welding along the circumference of a joint surface between a center electrode base metal and a noble metal tip in excess of full circumference. When G represents a spark gap and A represents a shortest gap between a laser weld bead and a line drawn parallel with axis X, A?3G. Straight lines S1 and S2 which connect the center of the noble metal tip 1 and the circumferential center of a proximal end 52 of the ground electrode 51 and vertex 8 of a protrusion 7 formed at a final end portion 6e of a bead 6 formed by circumferential laser welding, respectively, form an angle ? of 45 degrees. Since the protrusion 7 of the bead is the angle ? away from the ground electrode 51, an abnormal discharge is unlikely to be generated.

Abstract: An optical joint (1) includes a 2×2 MMI coupler (30) and a 2×2 MMI coupler (31) joined to the 2×2 MMI coupler (30). The 2×2 MMI coupler (30) includes a port (32) and a port (33) at one side. The 2×2 MMI coupler (31) includes a port (34) and a port (35) at one side. A light-absorbing region (20) is connected to the port (33), and a light-absorbing region (second light-absorbing section) (21) is connected to the port (34). A reflecting boundary (22) that reflects light propagated through the 2×2 MMI coupler (30) or the 2×2 MMI coupler (31) is formed at the junction portion between the 2×2 MMI coupler (30) and the 2×2 MMI coupler (31).

Abstract: There are provided a spark plug in which a plating film applied to a ground electrode can be relatively easily removed, without cost increase, to prevent deterioration in ignition performance, and a process for producing the spark plug. A spark plug 1 has a metal shell 3, a ground electrode 27 made of a Ni alloy and a Ni plating layer 28 containing Ni as a main component and applied to surfaces of at least a rear end portion of the ground electrode 27 and of the metal shell 3. A Ni plating film 41 applied to a center-electrode-side part of a portion of the ground electrode 27 to be bent has been irradiated with a laser beam or the like, thereby forming a molten layer 29 in which metal materials of the Ni plating film 41 and the ground electrode 27 are molten together on the center-electrode-side part of the portion of the ground electrode 27 to be bent. The Ni plating layer 28 is formed on a part of the ground electrode 27 other than the part irradiated with the laser beam.

Abstract: A manufacturing method for an ignition plug is provided. The method includes: preparing an insulator having a cavity provided at a leading end portion thereof by disposing a leading end of the center electrode more inwards than a leading end of the insulator; building the insulator in an interior of the metal shell such that the leading end of the insulator is situated closer to a rear end side than the leading end of the metal shell; removing at least part of a leading end portion of the metal shell which projects from a leading end face of the insulator; and disposing the ground electrode at the leading end portion of the metal shell and welding the ground electrode and the metal shell together after the removal step.

Abstract: A first exemplary aspect of the present invention is a wavelength-tunable optical transmitter including: a semiconductor substrate (101); a wavelength-tunable light source that is formed on the semiconductor substrate (101) and includes at least a first reflector (102) of a wavelength-tunable type and a gain region (104); a semiconductor optical modulator formed on the semiconductor substrate (101); a first semiconductor optical waveguide (105c) that is formed on the semiconductor substrate (101) and smoothly connected to the wavelength-tunable light source; a second semiconductor optical waveguide (105d) that is formed on the semiconductor substrate and smoothly connected to the semiconductor optical modulator; a waveguide coupling region (108) in which the first and second semiconductor optical waveguides are collinearly coupled with a length LC that is not equal to m/2 (m: integer) times a complete coupling length LC0; and a second reflector (113) formed at an end of the waveguide coupling region (108).

Abstract: A spark plug includes a ground electrode formed with a flat region and a convex curved region on an outer peripheral surface thereof. The flat region is located on a front end of the ground electrode and has a length of 0.2 mm or more from a front end face of the ground electrode in a longitudinal direction of the ground electrode. The ground electrode satisfies the following dimensional condition (1) with respect to first and second cross sections of the ground electrode taken through the convex curved region and the flat region in directions perpendicular to the longitudinal direction of the ground electrode, 0.950?(S2/L2)/(S1/L1)?0.995 ??(1) where S1 is the area of the first cross section; L1 is the perimeter of the first cross section; S2 is the area of the second cross section; and L2 is the perimeter of the second cross section.

Abstract: A method of producing a spark plug includes reducing the diameter of a center electrode while maintaining the heat dissipation property of the center electrode. A columnar member in which an outer skin member and a core member having a high thermal conductivity are clad, and which is columnarly extended, are configured by extrusion molding into a state where the thickness of the outer skin member is substantially uniform. A flange portion and a tip end portion are formed in the columnar member to obtain an electrode intermediate member. In a middle trunk portion of the electrode intermediate member, the thickness of the outer skin member is maintained. Then, the surface of the middle trunk portion is cut or polished to reduce the thickness, whereby the diameter of a center electrode is reduced while maintaining the outer diameter of the core member.

Abstract: A plasma jet spark plug comprising: a center electrode; an insulator having an axial bore extending in an axial direction, and retaining the center electrode within the axial bore; a metallic shell surrounding and retaining the insulator from outside with respect to a radial direction perpendicular to the axial direction; and a ground electrode disposed frontward of the front end portion of the insulator with respect to the axial direction, wherein the ground electrode has a contact portion contacting the front end portion of the insulator in an annular contact zone, the ground electrode is not in contact with the metallic shell with respect to the axial direction and the ground electrode is in contact with the metallic shell with respect to a radial direction perpendicular to the axial direction and is electrically connected with the metallic shell by means of an outer peripheral portion thereof being joined to the metallic shell.

Abstract: A spark plug is provided capable of speedily burn off carbon adhered on an insulator. With this spark plug, in order to improve the temperature rise performance of a front end side of an insulator 10, an amount of protrusion H (mm) of the insulator 10, a front-end side volume Vi (mm3) of the insulator 10, and a front-end side volume Vc (mm3) of a center electrode 20 are respectively defined. In consequence, it is possible to improve the recovery property of carbon fouling while retaining the voltage resistance of the insulator 10 and the durability of the center electrode 20. In addition, since the recovery property of carbon fouling improves, it is possible to prevent the occurrence of side sparks generated from the center electrode 20 to a metal shell 50 along the insulator 10, thereby making it possible to stably ensure proper ignition of an air-fuel mixture.

Abstract: When an insulator of a spark plug receives an external force in a bending direction perpendicular to an axis at a rear end side body portion, a position C where the insulator is supported by a crimping portion via a packing acts as a fulcrum, and a stress is applied between the position C and a position B where the insulator is supported by a ledge portion via a packing. When an insulator is designed in which the balance of size and modulus of section is adjusted so that ?A which denotes a proof strength against bending between a rear end position A of the insulator and the position C and ?B which denotes a proof strength against bending between the position B and the position C satisfy 0.71??A/?B?1.27, cracks can be prevented.

Abstract: A method of producing a spark plug includes reducing the diameter of a center electrode while maintaining the heat dissipation property of the center electrode. A columnar member in which an outer skin member and a core member having a high thermal conductivity are clad, and which is columnarly extended, are configured by extrusion molding into a state where the thickness of the outer skin member is substantially uniform. A flange portion and a tip end portion are formed in the columnar member to obtain an electrode intermediate member. In a middle trunk portion of the electrode intermediate member, the thickness of the outer skin member is maintained. Then, the surface of the middle trunk portion is cut or polished to reduce the thickness, whereby the diameter of a center electrode is reduced while maintaining the outer diameter of the core member.

Abstract: Provided is a traveling-wave type semiconductor optical phase modulator capable of high speed and low voltage operation by improving an n-SI-i-n-type layered structure. A first exemplary aspect of the present invention is a waveguide-type semiconductor optical modulator including: a semiconductor substrate (101); a first n-type cladding layer (103) and a second n-type cladding layer (108) formed on the semiconductor substrate (101); an undoped optical waveguide core layer (104) and an electron trapping layer (107) formed between the first n-type cladding layer (103) and the second n-type cladding layer (108); and a hole supplying layer (106) formed between the undoped optical waveguide core layer (104) and the electron trapping layer (107).

Abstract: An isolation portion (P) of an insulator (10) of a spark plug (100) electrically insulatively isolates a front end portion (22) of a center electrode (20) and a holding portion (56) of a metallic shell (50) from each other and has an intermediate portion (P2) which extends while its outside diameter varies, thereby ensuring an insulation distance between the two portions. The ratio (S/V) of the surface area (S) of the outer surface (14) of the isolation portion (P) to the volume (V) of the isolation portion (P) satisfies the relation 1.26 mm?1?S/V, whereby the insulation distance between the front end portion (22) and the holding portion (56) is sufficiently ensured while existing dimensional conditions are held unchanged. Through satisfaction of the relation S/V?1.

Abstract: A spark plug and manufacturing method. The spark plug (1) includes a metallic shell (3) extending along an axis CL1, a ceramic insulator (2), a center electrode (5), and a ground electrode (27) having a base end portion joined to a front end face (26) of the metallic shell (3). The method includes assembling the metallic shell (3) and a center electrode assembly (41); and joining the ground electrode (27) to the front end face (26). The distance between a reference plane SP perpendicular to the axis CL1 and the front end face (26) as measured along the axis CL1 varies in the circumferential direction. In the joining step, the position of the distal end portion of the ground electrode (27) relative to the front end portion of the center electrode assembly (41) along the axis CL1 is adjusted by changing the region of the front end face (26) to which the ground electrode (27) is joined.