Abstract: This spark plug inhibits excessive increase in the temperature of a ground electrode to inhibit occurrence of pre-ignition. The spark plug includes: an insulator in which an axial hole extending in an axial line direction is formed; a center electrode disposed at a front end in the axial line direction of the axial hole and having a front end portion that protrudes from a front side of the axial hole; a tubular metal shell holding the insulator; and a ground electrode having one end portion that is fixed to a through hole provided in the metal shell, the ground electrode further having another end portion that forms a discharge gap between the other end portion and the front end portion of the center electrode. The through hole extends toward the front side in the axial line direction, in a direction from an outer peripheral surface toward an inner peripheral surface of the metal shell. The one end portion is located on a rear side relative to the other end portion in the axial line direction.

Abstract: A waveguide includes a dielectric substrate, a first conductor layer and a second conductor layer formed on a lower surface and an upper surface thereof, a pair of side wall parts forming side walls of both sides of the waveguide, and a feed part feeding an input signal to the waveguide. The feed part includes a feed terminal formed on the lower surface of the dielectric substrate and does not contact the first conductor layer, a first via conductor connected at a lower end thereof to the feed terminal, a first connection pad connected to an upper end of the first via conductor, and second via conductors that are each connected at a lower end thereof to the first connection pad. The sum of the cross-sectional areas of the second via conductors is greater than the sum of the cross-sectional area of the first via conductor.

Abstract: An ultrasonic generator includes an ultrasonic wave source and a converging portion. The converging portion includes a first reflecting portion which reflects the ultrasonic wave generated by the ultrasonic wave source on its first reflecting surface, a second reflecting portion which reflects the ultrasonic wave reflected by the first reflecting surface on its second reflecting surface, and a waveguide serving as a transmission path for the ultrasonic wave. The waveguide is disposed such that the ultrasonic wave reflected by the second reflecting surface is introduced through an introduction portion thereof. The focal point of the second reflecting surface and the focal point of the first reflecting surface are disposed such that the ultrasonic wave reflected by the second reflecting surface becomes a plane wave.

Abstract: Disclosed is a gas sensor element having: a solid electrolyte body containing oxygen-ion conductive ZrO2; a detection electrode disposed on the solid electrolyte body to be exposed to a gas under measurement; and a reference electrode disposed on the solid electrolyte body to be exposed to a reference gas. In the gas sensor element, the detection electrode contains Pt and ZrO2; the detection electrode has a thickness of 3 to 10 ?m; the amount of ZrO2 contained relative to Pt in the detection electrode is 12 to 18 wt %; the detection electrode has a porosity of 5% or lower; and, in a particle size distribution graph of ZrO2 particles in the detection electrode, a cumulative value of peaks appearing in a range of 0.025 ?m to 0.200 ?m is 60 to 75%, and a cumulative value of peaks appearing in a range of 1.000 ?m to 3.162 ?m is 2 to 7%.

Abstract: One aspect of the disclosure provides an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al2O3 crystal grains and crystal grains represented by formula (Y,A)3B5O12:Ce. In the optical wavelength conversion member, a (Y,A)3B5O12:Ce crystal grain has a region wherein the A concentration of a peripheral portion of the (Y,A)3B5O12:Ce crystal grain is higher than that of an interior portion of the (Y,A)3B5O12:Ce crystal grain. Thus, the optical wavelength conversion member exhibits high fluorescence intensity (i.e., high emission intensity) and high heat resistance (i.e., low likelihood of temperature quenching). The optical wavelength conversion member has a structure wherein the element A concentration of a peripheral portion of a (Y,A)3B5O12:Ce crystal grain differs from that in an interior portion of the crystal grain.

Abstract: A first ceramic member and a second ceramic member are joined together at a lower joining temperature while reducing the loss of bond strength. A method for producing a semiconductor production device component includes a step of providing a first ceramic member including an AlN-based material, a step of providing a second ceramic member including an AlN-based material, and a step of joining the first ceramic member and the second ceramic member to each other by thermally pressing the first ceramic member and the second ceramic member to each other via a joint agent including Eu2O3, Gd2O3 and Al2O3 disposed between the first ceramic member and the second ceramic member.

Abstract: A cutting tool (1) formed of a silicon nitride-based sintered body (2) including a matrix phase (3), a hard phase (4), and a grain boundary phase (10) in which a glass phase (11) and a crystal phase (12) exist. The sintered body (2) contains yttrium in an amount of 5.0 wt % to 15.0 wt % in terms of an oxide, and contains titanium nitride as the hard phase (4) in an amount of 5.0 wt % to 25.0 wt %. In an X-ray diffraction peak, a halo pattern appears at 2? ranging from 25° to 35° in an internal region of the sintered body (2). A ratio B/A of a maximum peak intensity B to a maximum peak intensity A satisfies 0.11?B/A?0.40 . . . Expression (1) in a surface region of the sintered body (2), and satisfies 0.00?B/A?0.10 . . . Expression (2) in the internal region of the sintered body (2).

Abstract: A spark plug which includes an insulator having an axial hole extending along an axial line, a metallic shell disposed around the insulator, and a center electrode disposed in the axial hole to be located on the forward end side of the axial line is provided. The insulator has a step portion provided on the outer circumferential surface thereof and facing toward the forward end side. The metallic shell has a receiving surface provided on the inner circumferential surface thereof and facing toward the rear end side and with which the step portion is engaged via a packing. A portion of the step portion on the outer circumferential side is a first curved surface being convex toward the forward end side, and a portion of the step portion on the inner circumferential side of the first curved surface is a second curved surface which being convex toward the rear end side.

Abstract: A NOx sensor element includes: a first pump cell configured to adjust an oxygen concentration in a first measurement chamber; a diffusion resistance portion configured to adjust a diffusion rate of a measurement target gas introduced into the first measurement chamber; and a second pump cell in which a pump current corresponding to a NOx concentration in the measurement target gas after the adjustment of the oxygen concentration, flows. The first pump cell includes: a first solid electrolyte; an inner pump electrode containing a noble metal, and exposed to the first measurement chamber; and an outer pump electrode containing a noble metal, and disposed outside the first measurement chamber. The outer pump electrode contains not less than 22% by mass of a main component of the first solid electrolyte.

Abstract: A package has a package body formed by stacked insulating layers and having a front surface including a mounting area, a back surface and a side surface; a plurality of hollow portions arranged so as to be adjacent to each other on the front surface of the package body; a plurality of electrode pads individually placed on respective bottom surfaces of the hollow portions; and a partition wall formed by at least one insulating layer that forms the package body and having protruding banks at its both edge sides. Surfaces of the electrode pads are located at a lower position with respect to the front surface of the package body. The hollow portions are arranged at opposite sides of the partition wall. The electrode pads are electrically connected to respective conductor layers that are formed on the back surface and/or the side surface of the package body.

Abstract: A method for manufacturing a sensor element that includes: a pair of electrodes; a ceramic layer having a hollow space that is to be an air introduction hole; and a first layer and a second layer stacked at both surfaces of the ceramic layer, One of the electrodes is in communication with the hollow space, The method includes: preparing an unsintered ceramic sheet, and a burn-out material sheet having a thickness different from that of the unsintered ceramic sheet, the burn-out material sheet having, in a plane orthogonal to the direction of an axial line O, a cross-sectional area substantially identical to a cross-sectional area of the pre-sintering hollow space; placing the burn-out material sheet in the pre-sintering hollow space; pressing the sheets so as to have an identical thickness; and burning out the burn-out material sheet.

Abstract: A gas sensor (100) extending in an axial direction AX including: a gas sensor element (120) which detects the concentration of a specific gas in a gas under measurement; a tubular metallic shell (110) having a polygonal tool engagement portion (110B) surrounding the gas sensor element (120); a tubular outer tube (103) which extends rearward from the metallic shell (110), surrounds the gas sensor element (120), and has an opening (103E) at a rear end thereof; a sealing member (191) which seals the opening (103E); and a tubular heat dissipating member (104) which surrounds the outer tube (103) and reduces the amount of heat transferred from the forward end side of the gas sensor (100) through the outer tube (103) to the sealing member (191). The maximum diameter D1 of the heat dissipating member (104) is equal to or less than the opposite side dimension D2 of the tool engagement portion (110B).

Abstract: A spark plug capable of generating a sufficient volume of jet with an increased range is provided. The spark plug includes a metal shell having a tubular shape; a center electrode retained in the metal shell in an insulated manner; a ground electrode that is electrically connected to the metal shell and that defines a spark gap between the center electrode and an end portion of the ground electrode; and a cap portion that covers the center electrode and the end portion of the ground electrode from the front in a region in front of the metal shell and in which a through hole is formed. The cap portion includes a plurality of projections on an inner surface of the through hole. The projections extend in an extending direction in which the through hole extends.

Abstract: A holding device includes: a plate-shaped member having a first surface approximately orthogonal to a first direction; heat generating resistors and temperature measuring resistors disposed in respective segments formed by virtually dividing at least part of the plate-shaped member, the segments being arranged in a direction orthogonal to the first direction; and an electricity supply section that forms electricity supply paths for the heat generating resistors and the temperature measuring resistors. The holding device holds an object on the first surface of the plate-shaped member. The position of the temperature measuring resistors in the first direction differs from the position of the heat generating resistors in the first direction. A specific temperature measuring resistor that is at least one of the temperature measuring resistors includes a plurality of resistor elements disposed at different positions in the first direction and connected to one another in series.

Abstract: A spark plug includes a center electrode, a tubular metallic shell which holds the center electrode therein in an insulated state, and a ground electrode which faces a forward end portion of the center electrode. The metallic shell has a penetration hole which penetrates the metallic shell in a direction intersecting an axial direction. The ground electrode has a press-fitted portion inserted into the penetration hole and fixed to the metallic shell, a projecting portion projecting toward an inner side of the metallic shell, and an insertion portion disposed between the press-fitted portion and the projecting portion, inserted into the penetration hole, and forming a space between the insertion portion and an inner surface of the penetration hole. An angle ? formed between the inner surface of the penetration hole and an outer surface of the insertion portion falls within a range of 0°<?<90°.

Abstract: [Object] To prevent a sealant from intruding between a flange and a stepped portion during manufacture of a spark plug and to prevent cracking of an insulator during use of the spark plug. [Solution] A spark plug includes a center electrode including a flange, an insulator having a through-hole extending in an axial-line direction and holding the center electrode, and a sealant filled in the through-hole to fix the flange and the insulator to each other. The insulator includes a stepped portion in which the through-hole reduces a diameter toward a front end side and that supports the flange, and a small-diameter portion that is continuous with a front end side of the stepped portion and in which the diameter of the through-hole is smaller than in the stepped portion. An angle ?1 formed by the stepped portion and a plane perpendicular to the axial line and an angle ?2 formed by the plane perpendicular to the axial line and an opposing surface of the flange opposing the stepped portion satisfies ?1??2?6°.

Abstract: The hydrogel includes a first network structure and a second network structure. The second network structure is entwined with the first network structure. The first network structure contains a polymer crosslinked with a first crosslinking agent. The second network structure contains a polymer crosslinked with a second crosslinking agent. 50 mol % or more of the first crosslinking agent does not contain a decomposable bond. 50 mol % or more of the second crosslinking agent does not contain a decomposable bond.

Abstract: A spark plug that prevents a decrease in strength of a member to which a mark is attached while ensuring a readability of the mark, and a method of manufacturing the spark plug. The spark plug is configured to ignite an air-fuel mixture in an internal combustion engine. The spark plug includes: a mark formed of an oxide film generated on a surface of a metallic member or is formed of the metallic member and the oxide film; and a coating material covering the whole mark and allowing transmission of light.

Abstract: The spark plug includes a cylindrical insulator, a center electrode provided in the insulator, and a cylindrical metal shell provided around the insulator. A ledge portion of the metal shell has a frontward facing surface facing a front side, a rearward facing surface facing a rear side, and a connection surface connecting the rearward facing surface and the frontward facing surface. The rearward facing surface engages with a step portion of the insulator. The metal shell includes a front cylindrical portion connected to the front side of the ledge portion. The inner circumferential surface of the front cylindrical portion is connected to the frontward facing surface of the ledge portion via a chamfered surface or a rounded surface. A corner at which the connection surface and the frontward facing surface are connected is located on the front side with respect to a front end of the insulator.

Abstract: Disclosed is a manufacturing method of a gas sensor. The gas sensor has a plate-shaped sensor element with at least one pair of electrode pads, a separator disposed around the sensor element, and at least one pair of opposed metal terminals held in an insertion hole of the separator and electrically connected at contact regions thereof to the respective electrode pads. The manufacturing method includes mounting the metal terminals in the insertion hole of the separator with use of a mounting jig. The mounting jig has a flat portion interposed between the contact regions of the metal terminals during the mounting of the metal terminals in the separator so as to prevent contact and entanglement of the opposed metal terminals.