Abstract: A ceramic pin heating element having exterior heating conductors and integrated electrical connection surfaces, and method for making same. A first body is injection molded from a first injection-moldable ceramic composite compound having a first electrical resistance, and a second body is injection-molded from a second injection-moldable ceramic composite compound having a second electrical resistance about the first body so as to form a compound body. The compound body is then sintered. The resulting ceramic pin heating element is directly formed without additional steps for protecting (insulating) the element so as to prevent the exterior, complementary heating conductors from contacting the housing and/or terminal bolts. The danger of breakage of the pins at the mounting location and/or at the seal seat through variations in the thickness of contact and/or insulation coatings is minimized.

Abstract: A silicon nitride-tungsten carbide composite sintered material which contains silicon nitride and tungsten carbide, and characterized in that in an arbitrary cross-section of the sintered material, the ratio of the area of a tungsten carbide portion to that of the entirety of the cross-section is 20-35%, and a tungsten carbide aggregation portion having a longitudinal length of at least 5 &mgr;m is present in the arbitrary cross-section. The production process includes firing raw material powder containing tungsten carbide powder and two silicon nitride powders having different particle sizes.

Abstract: A ceramic micro-glow plug made from three primary constituents, silicon, carbon and nitrogen by forming a precursor liquid polymer in a mold or by photolithograpy, drying, pyrolizing and annealing. A U-shaped design with two arms joined at thin tip, and the composition of the silicon carbon-nitride ceramic allow the tip to reach a high operating temperature with a minimum power applied across the electrical contacts. When the tip is at the highest operating temperature, the remainder of the structure remains relatively cool. In an embodiment, an additional component such as boron is added to the silicon carbon-nitride to increase the electrical conductivity of the micro-glow plug. In another embodiment, a plurality of micro-glow plugs are attached to a body wherein when the operational micro-glow plug fails, the next successive micro-glow plug receives power across its electrical contacts.

Abstract: Robust ceramic igniters are provided that include an improved sealing system which can significantly enhance operational life of the igniter. Preferred igniters comprise a conductive cold zone and hot zone with higher resisitivity. A hermetic sealant material covers one or more electrical connections on the of each cold zone, thus shielding the electrical connections from environmental exposure, and thereby avoiding igniter failure resulting from electrical shorts and/or undesired oxidation.

Abstract: An ion flow measurement glow plug with an electrical terminal for the ignition current of a heating element which is located in a glow tube on an end which is directed to the combustion space of an engine block. The glow tube is located in a plug housing, insulated relative to the latter, and the plug housing is electrically connected to the engine block. At a terminal-side area of the plug, a solid-state switch is integrated or modulalry arranged, which is triggered by a control signal, as a result of which the second terminal of the heating element is switched to the engine block (ground) via the plug housing.

Abstract: There is provided a glow plug connection apparatus for installing a plurality of glow plug connectors to corresponding glow plugs mounted in a cylinder head in an internal combustion engine while simultaneously preventing engine oil leakage. The apparatus comprises a rigid buss bar rail, a plurality of glow plug connectors attached to the buss bar rail, a plurality of connector wires routed in the buss bar rail and connected to the glow plug connectors, a wire router, a conduit retaining clip, and an apparatus connector angle. Additionally, the glow plug connectors preferably comprises a buss bar rail interface section, a glow plug connector angle, a sealing section having an O-ring seal, a guide section having guide fins around the periphery of the glow plug connector, and a clip section having a clip fingers around the periphery of the glow plug connector able to engage a glow plug terminal.

Abstract: A ceramic heater includes a rod-shaped heater body provided with an insulating ceramic substrate, a heating resistor embedded in a front end portion of the ceramic substrate and a pair of first and second electric conductors embedded in the ceramic substrate with front end portions thereof electrically connected to the heating resistor and rear end portions thereof exposed at a rear end surface of the heater body. The ceramic heater further includes first and second lead-out members having front surfaces joined to parts of the rear end surface of the heater body via metallic layers so as to cover the exposed rear end portions of the first and second electric conductors, respectively, and to be kept from covering an outer circumferential surface of the heater body.

Abstract: A glow plug comprises a ceramic heater having an insulating ceramic substrate, a heating resistor embedded in a front end portion of the ceramic substrate and a pair of first and second electric conductors embedded in the ceramic substrate and electrically connected at front end portions thereof to the heating resistor, a metallic sleeve circumferentially surrounding the ceramic heater with a front end portion of the ceramic heater protruded from the metallic sleeve, a metallic shell fitted onto the metallic sleeve, and a central electrode partly disposed in a rear portion of the metallic shell. The first and second electric conductors have rear end portions exposed at a rear end surface of the ceramic heater and electrically connected to the metallic shell and the central electrode via first and second connecting members, respectively.

Abstract: Method of joining a rod-shaped heating element with a tubular carrier element involving attaching a cylindrical carrier ring to the rod-shaped heating element using a magnetic forming process and inserting the carrier ring and the rod-shaped heating element into the tubular carrier element such that the outer circumferential surface of the carrier ring contacts the inner circumferential surface of the tubular carrier element.

Abstract: A heater has a cylindrical metallic shell, a heater body partly disposed in a front end portion of the metallic shell, an electrode disposed in a rear portion of the metallic shell and electrically connected to the heater body, and a terminal adapted to be capped with an electric connector. The terminal includes a terminal body for power supply to the heater body through the electrode and an engaging portion formed on an outer circumferential surface of the terminal body so as to be engageable with the electric connector. The electrode and the terminal body are formed integrally with each other. Such a heater can maintain good electrical conduction from the terminal to the heater body with its simple structure throughout an extended period of time.

Abstract: A ceramic heater 1 includes a silicon nitride ceramic substrate 13 and a resistance-heating member 10 embedded in the silicon nitride ceramic substrate 13. The silicon nitride ceramic substrate 13 contains oxygen derived from a sintering aid at an average concentration of 0.4-3.2% by weight in a surface layer portion extending from the surface thereof to a depth of 1 mm. The ceramic heater 1 can be manufactured by firing through hot pressing. A firing jig for use in a firing process has an SiC—C composite layer which is formed therein along the surface of cavities thereof while having a predetermined depth as measured from the cavity surface.

Abstract: A sheathed element glow plug having an ionic current sensor and a method of operating such a sheathed element glow plug are provided. The sheathed element glow plug includes a housing and a rod-shaped heating element arranged in a concentric bore in the housing. The heating element has at least one insulation layer, a first feeder layer, and a second feeder layer, the first feeder layer and the second feeder layer being connected by a web on the combustion chamber-side end of the heating element, the first and second feeder layers and the web being made of an electrically conducting ceramic material, and the insulation layer being made of an electrically insulating ceramic material. The heating element has at least one ionic current detection electrode made of an electrically conducting ceramic material.

Abstract: An ion sensor glow plug assembly includes a metal shell for attachment to a cylinder head of a compression ignition engine. The ion sensor glow plug assembly also includes a center terminal at least partially disposed in the metal shell and connected to a source of power to create a heating circuit. The ion sensor glow plug assembly includes a metal glow sheath disposed at least partially in the metal shell and about the center terminal. The ion sensor glow plug assembly further includes an insulator disposed about the metal glow sheath and at least partially in the metal shell and extending axially into a glow area of the metal glow sheath to clean off soot on the insulator by glowing.

Abstract: A sheathed-element glow plug having an ionic-current sensor, as well as a method for operating a sheathed-element glow plug having an ionic-current sensor are described, the sheathed-element glow plug having a housing (3) and a rod-shaped heating element (5) arranged in a concentric bore hole of the housing. The heating element (5) has at least one insulating layer (11) as well as a first lead layer (7) and a second lead layer (9), the first lead layer (7) and the second lead layer (9) being connected via a bar (8) at end (6) of the heating element (5) on the combustion chamber side, the first and second lead layers (7, 9) and the bar (8) being made of electroconductive ceramic material, and the insulating layer (11) being made of electrically insulating ceramic material. The heating element (5) has a first electrode (33) for detecting ionic current and a second electrode (33′) for detecting ionic current which are embedded in the insulating layer (11) or are applied on the insulating layer (11).

Abstract: A heater 1 has a seal structure formed by inserting a shaft-like member 4 into a stepped bore 8 formed in a tubular member 2, and setting an O-ring 16 on an upper surface of a stepped portion of the stepped bore 8, a clearance 15 between the shaft-like member 4 and tubular member 2 being thereby sealed with this seal structure. A seal region 17 is formed on the upper surface of the stepped portion of the stepped bore 8, and a conical introduction port portion 18 extending divergently in the rearward direction from the seal region toward an opening of the stepped bore 8 is provided. Moreover, a cone angle &agr; of the introduction port portion 18 with respect to an axis L of the tubular member 2 is set to not larger than 35°.

Abstract: A sheathed-element glow plug including a glow plug body and a heating rod inside the glow plug body, and a heating element. Optionally, the glow plug includes a control element, embedded in insulating material, associated with said heating element which is positioned within the heating rod. The heating element, at the end facing the electrical connection, has an internal pole, with internal pole lead-in, for connection to a power source; while, the end of said heating element facing the combustion chamber is connected to the tip of the heating rod. The glow plug also includes a contact tube which is pushed onto the end region of the heating rod facing the electrical connection in order to extend the heating rod in the direction of the electrical connection to define a hollow space between the contact tube and the internal pole, internal pole lead-in, which is filled with insulating material.

Abstract: A method for fabricating electrically conductive silicon carbide articles by doping and sintering submicron silicon carbide particles using sub-micron alumina as the dopant source. Submicron alumina particles are made by milling aluminum powder. Despite the ductility of metallic aluminum, it is successfully ball milled in an aqueous medium through the creation and abrasion of successive layers of an alumina skin to yield alumina particles as small as 0.01 &mgr;m across. When suitably composed mixtures of the silicon carbide and alumina are molded into a green body and heated sufficiently in a non-oxidizing furnace atmosphere, the alumina breaks down to metallic aluminum which diffuses into the silicon carbide. The small particle sizes and the presence of a sintering aid enable rapid processing kinetics which favor saturation of the silicon carbide by the aluminum and inhibit grain growth.

Abstract: A heater comprising: a metal sheath; a heating element that is connected to the inner surface of the metal sheath at one end thereof; a center pole that is extending from an opening of the metal sheath to an interior of the metal sheath and directly or indirectly connected to the heating element; an insulating material that is packed in the interior of the metal sheath; and an elastic packing, wherein the opening of the metal sheath is closed by sealing of a gap between the metal sheath and the center pole with the elastic packing, and an axial length of a portion of the elastic packing, the portion is between the metal sheath and the center pole, is not smaller than 2.5 mm.

Abstract: A multi-layer ceramic heater for igniting fuel in a diesel engine having an electrode, an insulative layer disposed over the electrode, a resistive layer disposed over the insulative layer at the tip of the heater, and a conductive layer covering the insulative layer and extending from the resistive layer over the insulative layer to the base of heater. A substantial proportion of the volume of resistive layer is located in close proximity to the tip of heater. The resistive layer has a positive temperature coefficient (PTC) of electrical resistance and preferably a portion of the electrode is variably resistive for self regulation purposes. Due to the geometry of the resistive layer and the variable resistive characteristics of the resistive layer and the electrode, the heater is well suited to applications that require quick start heating as well as good afterglow properties or prolonged heating at high temperatures.

Abstract: To provide a ceramic heater which is better in the durability of an ion current detecting electrode portion and which can be manufactured at a low cost.

Abstract: A heater comprising: a cylindrical metal shell having an engagement portion, the portion having a narrowed diameter; a cylindrical heating tube comprising a closed top end, a fitting portion, a smaller diameter portion, a base end side-larger diameter portion and a top end side-larger diameter portion, wherein a base end of the heating tube protrudes into an inside of the metal shell, the fitting portion is fitted into the engagement portion in interference fit, the smaller diameter portion comprises the base end of the heating tube, the smaller diameter portion has a smaller outer diameter than an inner diameter of the engagement portion, the base end side-larger diameter portion is formed between the fitting portion and the smaller diameter portion, the base end side-larger diameter portion has an outer diameter larger than or equal to the inner diameter of the engagement portion, the top end side-larger diameter portion is formed adjacent to a top end side of the fitting portion, and the top end side-large

Abstract: A silicon nitride sintered material containing silicon nitride, a Group 4a through 6a element, a rare earth element, and silicon carbide, characterized in that the amount of the rare earth element as reduced to a certain oxide thereof is 5.7-10.3 mol %; the ratio by mol of subtraction remainder oxygen amount calculated in relation to the oxygen contained in the sintered material, the remainder oxygen amount being expressed in terms of silicon dioxide, to the amount of oxygen contained in the sintered material is at least 0.50 and less than 0.70; a four-component crystalline phase of rare earth element-silicon-oxygen-nitrogen is not present; and the thermal expansion coefficient is at least 3.7 ppm/° C. between room temperature and 1,000° C.

Abstract: A joint structure which does not exhibit impaired joining strength induced by exposure to heat cycles and the occurrence of migration, in a ceramic heater for a glow plug or like device. A heating element 6 is embedded in a silicon nitride ceramic substrate 5. Lead wires 15 are joined to corresponding lead wire connection terminals 11, which are connected to the heating element 6 while electrical continuity is established therebetween, by use of a brazing metal 20 which contains a predominant amount of copper. The brazing metal 20 used for joining assumes the form of a brazing metal layer having a thickness of 30-400 &mgr;m.

Abstract: The present invention is to provide a glow plug (1) with an ion current detecting function, which is mounted in a combustion chamber of a Diesel engine. The glow plug includes an insulator (8); a heating element (6) embedded in the insulator and energized through a pair of lead wires (11a, 11b) to generate heat; and an ion current detecting electrode (14) embedded in the insulator with a portion exposed into a flame in the combustion chamber so that an ionization state in the flame can be detected. The heating element of the glow plug promotes ignition and combustion of fuel in the combustion chamber (7) due to its heating action caused when running the heating element hot. The ion current detecting electrode detects an ionization state in the combustion flame. When detecting ion current, the ion current detecting electrode and the adjacent inner wall of the combustion chamber form two electrodes for capturing positive and negative ions existing between both when burning the fuel.

Abstract: A heater is provided which comprises a metallic shell, a heating element disposed at an end of the metallic shell, and a terminal electrode electrically connected to the heating element. The terminal electrode has a protruded portion protruding from the metallic shell. The protruded portion has a locking engagement section lockingly engageable with a connector for electrically connecting the terminal electrode to an outside for conduction of the heating element. A method of producing such a heater is also provided.

Abstract: A ceramic heater 1 is configured such that a ceramic resistor 10 includes a first resistor portion 11, which is disposed at a front end portion of a heater body 2, and which is formed of a first electrically conductive ceramic, and a pair of second resistor portions 12, which are disposed on the rear side of the first resistor portion 11 so as to extend along the direction of the axis O of the heater body 2. The front end parts of the second resistor portions 12 are joined to corresponding end parts of the first resistor portion 11 as viewed along the direction of electricity supply. The second resistor portions are formed of a second electrically conductive ceramic having an electrical resistivity that is lower than that of the first electrically conductive ceramic. At least a portion of a joint interface 15 between the first resistor portion 11 and each of the second resistor portions 12 deviates from a transverse plane P that perpendicularly intersects the axis O of the heater body 2.

Abstract: A ceramic heater 1 includes a rodlike heater body 2 configured such that a ceramic resistor 10 is embedded in a ceramic substrate 13. The ceramic resistor 10 includes a front end part 11a and two large-diameter rodlike portions Ld. The large-diameter rodlike portions Ld form passages for supplying electricity to the front end part 11a, extend rearward along a direction of an axis O of the heater body 2, and have an electricity-supply sectional area greater than that of the front end part 11a. The large-diameter rodlike portions Ld each have a connection end part connected to the front end part 11a. The connection end part is formed of a first electrically conductive ceramic and constitutes a first resistor portion 11. The remaining portion of each of the large-diameter rodlike portions Ld is formed of a second electrically conductive ceramic having an electrical resistivity lower than that of the first electrically conductive ceramic and constitutes a second resistor portion 12.

Abstract: A ceramic heater 2 is arranged in a metallic cylinder member 3 by forming a convergent taper portion 2t at the leading end 2a of the ceramic heater 2 and by positioning the leading end 3a of the metallic cylinder member 3 on the leading end side of a taper starting point P1 of the taper portion 2t. Solder is applied in the clearance between the inner circumference 3d of the metallic cylinder member 3 and the outer circumference 2b of the heater 2. An applied solder layer 10 is also formed on the leading end side of the taper starting point P1 of the taper portion 2t. The thick solder layer 10 present on the leading end side prevents a cut or broken off portion of the ceramic heater from separating or sliding out.

Abstract: A silicon nitride-tungsten carbide composite sintered material which contains silicon nitride and tungsten carbide, and characterized in that in an arbitrary cross-section of the sintered material, the ratio of the area of a tungsten carbide portion to that of the entirety of the cross-section is 20-35%, and a tungsten carbide aggregation portion having a longitudinal length of at least 5 &mgr;m is present in the arbitrary cross-section. The production process includes firing raw material powder containing tungsten carbide powder and two silicon nitride powders having different particle sizes.

Abstract: An ion sensor glow plug assembly includes a shell for attachment to a cylinder head of a compression ignition engine and having a passageway extending axially therethrough. The ion sensor glow plug assembly also includes a center terminal disposed at least partially in the passageway of the shell and connected to a source of power to create a heating circuit. The ion sensor glow plug assembly includes a glow sheath disposed at least partially in the passageway of the shell and about the center wire to create an ion sensing circuit. The ion sensor glow plug assembly further includes a coating disposed about a portion of the glow sheath between the glow sheath and the shell to isolate the shell from the glow sheath and extending axially into a glow area of the glow sheath to clean off soot on the glow sheath by glowing.

Abstract: Rod glow plug with a plug body and an internal heating rod. Between the heating rod (1) and the plug body (7) in the area of a seal seat of the rod glow plug, an electrically insulating shaped part (3) securely adjoins the heating rod (1) supporting the combustion space-side end (7a) of the plug body (7), electrically insulated from the heating rod (1).

Abstract: A glow plug for internal-combustion engines, comprising: a metal body (12); a metal sheath (24) having one closed end (26) and one open end (28); a terminal (30) extending through the open end (28) of the sheath (24); a conductive powder (34) set in electrical connection with one end (36) of the terminal (30) and with the sheath (24); and a layer (38) of insulating powder set between the aforesaid conductive powder (34) and the sheath (24) in an area between the closed end (26) of the sheath (24) and the end (36) of the terminal (30).

Abstract: A silicon nitride sintered material containing a silicon nitride component and silicon carbide having an average particle size of 1 &mgr;m or less in an amount of at least 1 mass % and less than 4 mass %, based on 100 mass % of the silicon nitride component. The carbide is dispersed in the silicon nitride component, and the silicon nitride sintered material has a thermal expansion coefficient of at least 3.7 ppm/° C. between room temperature and 1,000° C. The silicon nitride component contains a rare earth element in an amount of 15-25 mass % as reduced to a certain oxide thereof and Cr in an amount of 5-10 mass % as reduced to a certain oxide thereof, and a crystalline phase is present in intergrain regions of the sintered material.

Abstract: A glow plug (10) that includes a metal tubular body (12), a metal sheath (24) carried by the tubular body, a heating resistor (33) located inside the sheath, first and second electrical terminals (30,32), and a layer (36) of insulating material applied on a portion of the outer surface of the sheath. The first terminal (30) is electrically connected to the heating resistor (33) and the second terminal (32) is electrically connected to the sheath (24). The layer (36) of insulating material is located on the sheath (24) between the sheath and tubular body (12) to thereby electrically insulate the metal sheath from the metal tubular body. The layer (36) of insulating material can be applied by plasma deposition which enables the sheath (24) to be attached to the tubular body (12) by an interference fit of the sheath within a cavity (16) in the tubular portion. Also disclosed is a method of fabricating the glow plug (10).

Abstract: A glow plug in which a ceramic heater is fixedly disposed in a metallic, cylindrical member such that a front end thereof projects from a front end of the cylindrical member, and the resultant cylindrical member is fixedly disposed in a plug body such that the front end of the cylindrical member projects from a front end of the body, and which readily provides a mounting structure such that, even when loosening arises at a joint between the body and the cylindrical member after the glow plug is mounted onto a cylinder head, the cylindrical member is prevented from dropping into the interior of an engine. A portion 23 of a cylindrical member 3 projecting from a front end 4 of a plug body 4 has outside diameter D2, which is defined as a smaller diameter than a portion of the metallic, cylindrical member which is fixedly disposed within the metallic, cylindrical plug body (a large-diameter portion 33 of the cylindrical member 3).

Abstract: A glow plug (10) for diesel engines that includes a threaded metal tubular body (12) and a metal sheath (22) carried by the tubular body. The sheath (22) has an end portion (24) projecting from the tubular body (12) and is electrically insulated from the tubular body. The glow plug (10) includes first and second electrical terminals (30,46) and a heating resistor (34) electrically connected to the first terminal (30) and to the end portion (24) of the sheath (22). The first terminal (30) has the shape of a metal rod extending through the tubular body (12) and has an end inserted inside the sheath (22). The heating resistor (34) is also set inside the sheath (22). The second terminal (46) is electrically connected to the sheath (22) and can be disposed either coaxially around the first terminal (30) or coaxially within the first terminal.

Abstract: A glow plug for internal-combustion engines, comprising:

Abstract: A glow plug includes an inner pole and a ceramic heating rod disposed in and fixed to an outer shell at uppermost and lowermost pole fixed portions A, C and a heating rod fixed portion D. A ratio of L2/L1 is larger than 2, where L1 is a distance from the lower end of the inner pole to the lower end of the fixed portion C; and L2 is a distance from the lower end of the inner pole to the lower end of the fixed portion A. A ratio of L3/L4 is smaller than 15, wherein L3 is a distance from a middle point between the lower end of the inner pole and the upper end of the heating rod to the lower end of the fixed portion C; and L4 is a distance from the above middle point to the upper end of the fixed portion D.

Abstract: A silicon nitride—tungsten carbide composite sintered and process for preparing the same which contains silicon nitride and tungsten carbide, and is characterized in that the total in amounts of an entirety of rare earth elements as reduced to certain corresponding oxides thereof, the elements being contained in the sintered material, and excess oxygen as reduced to silicon dioxide is 6-20 mass %; the ratio, on a mol basis, of (the amounts of rare earth elements as reduced to the certain corresponding oxides thereof)/(the amounts of the rare earth elements as reduced to the corresponding oxides thereof+the amount of excess oxygen as reduced to silicon dioxide) is 0.3-0.7; a crystalline phase is present in an intergrain region of the sintered material; and an effective firing temperature range within which a flexural strength of at least 800 MPa is obtained encompasses at least 100 degrees.

Abstract: The present invention relates to ceramic igniter devices, and more particularly, to such devices that contain two or more segregated hot zone regions that are electrically connected such as in series or in parallel. These devices are suitably incorporated in a variety of devices, including diesel fuel filters.

Abstract: A glow plug includes an inner pole and a ceramic heating rod disposed in and fixed to an outer shell at uppermost and lowermost pole fixed portions A, C and a heating rod fixed portion D. A ratio of L2/L1 is larger than 2, where L1 is a distance from the lower end of the inner pole to the lower end of the fixed portion C; and L2 is a distance from the lower end of the inner pole to the lower end of the fixed portion A. A ratio of L3/L4 is smaller than 15, wherein L3 is a distance from a middle point between the lower end of the inner pole and the upper end of the heating rod to the lower end of the fixed portion C; and L4 is a distance from the above middle point to the upper end of the fixed portion D.

Abstract: A ceramic heater extending in an axial direction to have an elongate shape includes (a) a basal body; (b) a lead wire embedded in the basal body; and (c) a heating element embedded in the basal body. This heating element includes (1) a matrix ceramic phase; (2) conductive ceramic particles dispersed in the matrix ceramic phase; (3) a portion in which an end portion of the lead wire is embedded; and (4) a reference zone in terms of concentration of a particular element (e.g., rare-earth element). The heating element may include a condensed zone in terms of concentration of the particular element. The ceramic heater can be free from the condensed zone, or at least its formation is minimized to have a thickness of not greater than 5 &mgr;m. With this, the ceramic heater is improved in bending strength.

Abstract: The invention provides a glow plug with an electric resistor made of a material comprising 20 to 60% by weight nickel and less than 5% by weight iron and the balance of cobalt and unavoidable impurities. The glow plug pf the invention attains an excellent quick heating ability, a self-temperature control function, high oxidation resistance, long durability and good workability.

Abstract: In a glow plug controller, a glow plug 10 fixed to an engine 30 comprises a heater 4 and a ceramic substrate 2 having an exposed portion 2d which is exposed to the interior of a combustion chamber 32. A glow plug control apparatus 100 causes ECU 105 to control the energization of the heater 4 of the glow plug 10 to keep the surface temperature Ts of the exposed portion 2d to not lower than 500° C. Further, ionic current Ii is measured using the glow plug 10. Switches 102 and 103 switch from the energization of the glow plug to the detection of ionic current or vice versa in response to a command signal from ECU 105.

Abstract: A low cost process for self-forming a uniformly adherent protective rare earth silicate coating on a silicon-based ceramic component for protecting the component against corrosive/erosive environments. The coating is self-formed by an oxidation process of a silicon-based ceramic associated with a reaction between a silica (SiO2) film layer on the surface of silicon-based ceramic and the rare earth oxide existing inside of silicon-based ceramic component.

Abstract: A multi-layer ceramic heater for igniting fuel in a diesel engine having an electrode, an insulative layer disposed over the electrode, a resistive layer disposed over the insulative layer at the tip of the heater, and a conductive layer covering the insulative layer and extending from the resistive layer over the insulative layer to the base of heater. A substantial proportion of the volume of resistive layer is located in close proximity to the tip of heater. The resistive layer has a positive temperature coefficient (PTC) of electrical resistance and preferably a portion of the electrode is variably resistive for self regulation purposes. Due to the geometry of the resistive layer and the variable resistive characteristics of the resistive layer and the electrode, the heater is well suited to applications that require quick start heating as well as good afterglow properties or prolonged heating at high temperatures.

Abstract: The invention provides a glow plug with an electric resistor made of a material comprising 20 to 60% by weight nickel and less than 5% by weight iron and the balance of cobalt and unavoidable impurities. The glow plug of the invention attains an excellent quick heating ability, a self-temperature control function, high oxidation resistance, long durability and good workability.

Abstract: A glow plug including a heating rod having a plug body composed of an electrically insulating plastic material, an inner pole connected to heating elements, and optionally, control elements, and an outer pole which is electrically insulated from adjoining components of the plug body by an insulative material provided between an inner and outer support tube, the inner support tube surrounding the heating rod while the plug body surrounds the outer support tube.

Abstract: In a glow plug controller, a glow plug 10 fixed to an engine 30 comprises a heater 4 and a ceramic substrate 2 having an exposed portion 2d which is exposed to the interior of a combustion chamber 32. A glow plug control apparatus 100 causes ECU 105 to control the energization of the heater 4 of the glow plug 10 to keep the surface temperature Ts of the exposed portion 2d to not lower than 500° C. Further, ionic current Ii is measured using the glow plug 10. Switches 102 and 103 switch from the energization of the glow plug to the detection of ionic current or vice versa in response to a command signal from ECU 105.

Abstract: A glow plug and a process for joining a heating rod of a glow plug to a glow plug body such that a centered force fit between the heating rod and the glow plug body is produced by the radial force acting on the glow plug body.