Abstract: Provided are a casting die inspection method and a casting device, the method including: a step for acquiring the ultimate pressure in a cavity section, at the time when a prescribed vacuuming time has elapsed since evacuation the inside of the cavity section of the casting die was started; a step for evacuating the inside of the cavity section and acquiring an increased pressure in the cavity section that has increased during a prescribed stop time, at the time when the prescribed stop time has elapsed since the evacuation was stopped; a step for evaluating a first sealing property of the casting device on the basis of the ultimate pressure; and a step for evaluating a second sealing property of the casting device on the basis of the increased pressure.

Abstract: Provided is a sensor element for use in measurement of the concentration of a predetermined gas component in a measurement target gas. The sensor element includes a plate-shaped element body and a protective layer. The element body includes a solid electrolyte layer having oxygen ion conductivity and a heater configured to heat the solid electrolyte layer. A protective layer is formed on at least one face of the element body. A surface of the protective layer has a surface roughness Ra of 8 ?m or less and a surface waviness Wa of 6 ?m or more.

Abstract: A gas sensor sensing a sensing target gas component contained in a measurement gas and identifying concentration of the sensing target gas component includes: a sensor element having an inlet for the measurement gas on one end portion, and including: an element base made of an oxygen-ion conductive solid electrolyte; a heater buried in the element base; and a porous leading-end protective layer covering a predetermined range of the element base on the one end portion; and a metallic member within which the sensor element is fixedly disposed, wherein a minimum distance between the sensor element and an inner surface of the metallic member is 0.20 mm or more and 0.95 mm or less, and a portion of the inner surface of the metallic member closest to the sensor element has an arithmetic average roughness of 5 ?m or less.

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having an inlet at one end portion thereof; at least one internal chamber located inside the ceramic body, and communicating with the inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chamber, and a solid electrolyte located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a leading end surface and a region to be coped with water-induced cracking specified in advance. A single heat insulating space is interposed between the leading-end protective layer and a whole side surface of the element base at least in the above region.

Abstract: A sensor element includes: an inner protective layer having a porosity of 30% to 65% on two main surfaces; an intermediate protective layer having a porosity of 25% to 80%, which is equal to or smaller than the porosity of the inner layer; and an outer protective layer surrounding an element base on an outermost periphery on the one end portion of the element, and having a porosity of 15% to 30%, which is smaller than the porosity of the intermediate layer, wherein these layers are laminated in this order at least in a range in which the at least one inner chamber is provided in the element base, the outer is in contact with the inner layer in a range in which the at least one inner chamber is not provided, and a difference of porosity between the inner layer and the outer layer is 10% to 50%.

Abstract: A sensor element includes: an inner protective layer having a porosity of 30% to 65% on two main surfaces; an intermediate protective layer, at least a part of which has contact with the inner layer, and having a porosity of 25% to 80%, which is equal to or smaller than the porosity of the inner layer; and an outer protective layer surrounding an element base on an outermost periphery on the one end portion of the sensor element, having contact with the intermediate and the inner layer, having contact with a leading end surface of the element base or the intermediate layer on the leading end surface, and having a porosity of 15% to 30%, which is smaller than the porosity of the intermediate layer, wherein a difference of porosity between the inner and the outer layer is 10% to 50%.

Abstract: A sensor element includes: an element body including an oxygen-ion-conductive solid electrolyte layer; and a protective layer that covers at least part of the element body and is a porous body having a plurality of pores thereinside. The standard deviation of the porosity of the protective layer is 2.3% or less.

Abstract: A decompression path conductance factor calculation device 110 obtains a cavity pressure change characteristic representing a pressure change characteristic of a cavity portion 30 from an exhaust speed of a decompression device 70, a cavity conductance factor, an overflow conductance factor, a decompression path conductance factor, and respective volumes of inside spaces of a cavity portion 30, an overflow portion 50, and a decompression path 60, obtains a decompression path pressure change characteristic representing a pressure change characteristic of the decompression path 60 from the exhaust speed of the decompression device 70, the volume of the inside space of the decompression path 60, and the decompression path conductance factor, and obtains the decompression path conductance factor such that a difference between respective approximate curves representing the obtained cavity pressure change characteristic and the obtained decompression path pressure change characteristic becomes a threshold value or

Abstract: A gas sensor includes a solid electrolyte body with oxygen ion conductivity, a gas flow portion (ranging from a gas inlet port to a second inner cavity), a particular gas detector (including a main pump cell, a measurement pump cell, an auxiliary pump cell, etc.), and a control device. Prior to startup of the gas sensor, the control device sets electric power supplied to a heater such that a temperature difference between a temperature of the heater and a preset target temperature becomes zero, and determines, on the basis of the set electric power, whether temperature raising control of supplying the set electric power to the heater is to be executed.

Abstract: A gas sensor includes a sensor element and a contact metal fitting. The sensor element has an element body having an oxygen-ion-conductive solid electrolyte layer; an upper connector electrode disposed outside the element body; a lead disposed outside the element body and electrically conductive to the upper connector electrode; and a first protection layer that covers the lead, where a thickness T1 of a portion covering the lead is 2 µm or more, a porosity P1 is 20% or less, and a height difference D1 relative to the upper connector electrode is 22 µm or less. The contact metal fitting has: a conduction member that projects to the upper connector electrode and is in contact with and electrically conducted to the upper connector electrode; and a support member that projects toward the lead and is in contact with the first protection layer.

Abstract: A casting mold is provided with a cavity portion and an overflow portion, and the overflow portion is connected to a gas flow path (suction path). A valve (an on-off valve, a shut-off valve) is provided between the gas flow path and the overflow portion. A heating method for a casting mold includes a step of setting the pressure in the cavity portion to a second pressure by sucking gas in the overflow portion and in the cavity portion while the valve is kept open for a second time period shorter than a first time period during casting. The heating method further includes a step of heating the casting mold by supplying molten metal into the cavity portion set at the second pressure, and solidifying the molten metal.

Abstract: A sensor element for detecting a target gas to be measured in a measurement-object gas includes: an element body including an oxygen-ion-conductive solid electrolyte layer; and a protective layer covering at least a part of a surface of the element body. The protective layer includes a porous material that has a pore inside; and, in the pore in the protective layer, a ratio (Lt/Lf) of a pore length (Lt) in a thickness direction perpendicular to the surface of the element body to a pore length (Lf) in a surface direction perpendicular to the thickness direction is 0.6 to 0.9.

Abstract: A sensor element is used to detect the concentration of a predetermined component in a gas. The sensor element includes a sensor element body including a solid-state-electrolyte layer having oxygen-ion conductivity, an outer pump electrode that is disposed on an upper surface, which is one of the surfaces, of the sensor element body, and a porous protective layer that is provided so as to cover at least the outer pump electrode. A spatial layer is provided between the porous protective layer and the sensor element body. The spatial layer includes a first spatial layer between the porous protective layer and the outer pump electrode. The maximum-height roughness Rz of a region of the inner surface of the porous protective layer, the region facing the outer pump electrode, is 50 ?m or smaller.

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having a gas inlet at one end portion thereof; at least two internal chambers located inside the ceramic body, and communicating with the gas inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chambers, and solid electrolytes located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a part from a leading end surface to two internal chambers close to the gas inlet of the element base. A single heat insulating space is interposed between the leading-end protective layer and a portion of the element base in which the two internal chambers are located.

Abstract: A casting mold is provided with a cavity portion and an overflow portion, and the overflow portion is connected to a gas flow path (suction path). A valve (an on-off valve, a shut-off valve) is provided between the gas flow path and the overflow portion. A heating method for a casting mold includes a step of setting the pressure in the cavity portion to a second pressure by sucking gas in the overflow portion and in the cavity portion while the valve is kept open for a second time period shorter than a first time period during casting. The heating method further includes a step of heating the casting mold by supplying molten metal into the cavity portion set at the second pressure, and solidifying the molten metal.

Abstract: A casting mold includes a cavity portion, a gas flow path, and a shut-off valve capable of blocking the gas flow path. An inspection method for the casting mold includes: a step of, when the casting mold is cold, supplying air having a predetermined pressure into the gas flow path while the shut-off valve is closed, and thereafter stopping supply of the air; a step of acquiring a cold time pressure reduction rate of the air in the gas flow path after the supply of the air is stopped; and a step of determining whether the cold time sealing performance of the shut-off valve is good, based on the cold time pressure reduction rate.

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having an inlet at one end portion thereof; at least one internal chamber located inside the ceramic body, and communicating with the inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chamber, and a solid electrolyte located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a leading end surface and a region to be coped with water-induced cracking specified in advance. A single heat insulating space is interposed between the leading-end protective layer and a whole side surface of the element base at least in the above region.

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having a gas inlet at one end portion thereof; at least two internal chambers located inside the ceramic body, and communicating with the gas inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chambers, and solid electrolytes located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a part from a leading end surface to two internal chambers close to the gas inlet of the element base. A single heat insulating space is interposed between the leading-end protective layer and a portion of the element base in which the two internal chambers are located.

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having an inlet at one end portion thereof; at least one internal chamber located inside the ceramic body, and communicating with the inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chamber, and a solid electrolyte located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a leading end surface and a region to be coped with water-induced cracking specified in advance. A single heat insulating space is interposed between the leading-end protective layer and a whole side surface of the element base at least in the above region.

Abstract: A gas sensor includes a solid electrolyte body with oxygen ion conductivity, a resistance heating element imbedded in the solid electrolyte body, a gas flow portion provided in a fore end portion of the solid electrolyte body, a particular gas detector detecting particular gas in measurement object gas introduced to the gas flow portion and a controller setting, prior to startup of the gas sensor, electric power supplied to the resistance heating element such that a temperature in the fore end portion becomes equal to a preset target temperature, and determining, on basis of a temperature rise speed in the fore end portion when the set electric power is supplied to the resistance heating element, whether temperature raising control of supplying the set electric power to the resistance heating element is to be continued.