Abstract: A spark plug includes: a central electrode extending from a front end side to a rear end side along an axis; an insulator including a front end section formed to be a bottomed tube surrounding a tip of the central electrode; a metal shell shaped to be tubular and structured to support the insulator such that the front end section of the insulator projects to the front end side from a front end section of the metal shell; and a plurality of ground electrodes each of which includes a first end forming a discharge gap with the front end section of the insulator and includes a second end connected to the front end section of the metal shell. The plurality of ground electrodes include a pair of ground electrodes different from each other in size of their discharge gaps.

Abstract: A spark plug includes: a central electrode extending from a front end side to a rear end side along an axis; an insulator including a front end section formed to be a bottomed tube surrounding a tip of the central electrode; a metal shell shaped to be tubular and structured to support the insulator such that the front end section of the insulator projects to the front end side from a front end section of the metal shell; and a plurality of ground electrodes each of which includes a first end forming a discharge gap with the front end section of the insulator and includes a second end connected to the front end section of the metal shell. The plurality of ground electrodes include a pair of ground electrodes different from each other in size of their discharge gaps.

Abstract: In an ignition plug, since a ground electrode is formed in a thin-rod-shape or a mesh-like shape, sufficiently strong radicals are locally generated by a barrier discharge, an anti-inflammation effect by the electrode is small, and the growth of a flame is hardly hindered. Furthermore, by making the thickness dimension of a second dielectric facing a discharge region uniform, the barrier discharge is spread over the surface of the second dielectric, the generation of the radicals is maintained, and combustibility after ignition is promoted. Furthermore, because an end portion of a high voltage electrode and a ground electrode are disposed to face each other within a combustion chamber, a fuel gas introduced into the combustion chamber is liable to flow into the discharge region, and is easily ignited by the radicals generated due to the discharge.

Abstract: A spark plug ground electrode assembly including a ground electrode having a ground electrode base defining a receptacle. A base flange extends about less than an entirety of the receptacle to define an open lateral end of the receptacle. The open lateral end of the receptacle is arranged to receive a ground electrode pad slid into the receptacle and onto a support surface in a direction perpendicular to a spark plug longitudinal axis. The flange of the ground electrode pad is arranged between the base flange and the support surface to restrict movement of the ground electrode pad along the spark plug longitudinal axis. A welding is at the open end of the receptacle to restrict movement of the ground electrode pad in the direction perpendicular to the spark plug longitudinal axis.

Abstract: A spark plug is provided which includes a cylindrical metal shell, a cylindrical porcelain insulator retained in the metal shell, a center electrode, and a ground electrode. The center electrode is disposed in the insulator with a head protruding outside a front end surface of the insulator. The ground electrode is joined to the metal shell and includes a gap-defining portion which faces a side surface of a side surface of the center electrode to define a spark gap and also faces the front end surface of the porcelain insulator to define a semi-surface discharge gap for burning off, for example, carbon deposits on the front end surface of the insulator.

Abstract: A spark plug includes a housing, a center electrode disposed within the housing, and a ground electrode cooperating with the center electrode to generate a spark. The ground electrode further includes an arm having a main body and a base, a pad fixed to the base, and a covering affixed to at least one of the main body and the base. The main body is fixed to the housing. The covering alters a dielectric constant of the main body or a dielectric constant of the base to create a difference in the dielectric constant of the main body and the dielectric constant of the base and focus the spark on the pad.

Abstract: An ignition system that uses a technique capable of restraining radiation of noise caused by discharge of a spark plug in the ignition system. The ignition system includes a spark plug and a power supply section. The spark plug is attached to an engine head. The power supply section has a battery having a ground terminal, and an ignition coil which transforms a voltage of the battery and supplies a transformed voltage to the spark plug. In the ignition system, a metallic shell of the spark plug is fixed to the engine head while being electrically insulated from the engine head through an insulator; an electrically conductive path is connected to the metallic shell; and the electrically conductive path is electrically connected to the ground terminal of the battery while being electrically insulated from the engine head.

Abstract: A spark plug for a gas-powered internal combustion engine, having a center conductor, an insulator surrounding the center conductor, a body surrounding the insulator, a center electrode connected in an electrically conductive manner to the center conductor, and at least one ground electrode that is connected in an electrically conductive manner to the body and forms a spark air gap with the center electrode. A shield that shields the spark air gap in the radial direction of the spark plug is located at the front end of the body. The shield includes multiple shield components that are attached to the front end of the body adjacent to one another in the circumferential direction of the spark plug.

Abstract: Methods and systems are provided for inferring spark plug fouling due to accumulation of fuel additives thereon. In one example, an engine controller may infer spark plug fouling due to accumulation of fuel additive based on a combination of engine operating parameters correlated with spark plug health. For example, the engine operating parameters may include a change in an adaptive knock term, an engine pre-ignition rate, and engine exhaust oxygen sensor switching frequency over a vehicle drive cycle, and an engine misfire rate.

Abstract: Spark plug for an internal combustion engine, having a center electrode and a ground electrode. A spark gap is formed between the center electrode and ground electrode for igniting a fuel mixture by an electric ignition spark developing between the center electrode and the ground electrode. The center electrode and the ground electrode are contoured such that a ratio of a surface of the center electrode and the ground electrode, which is available for development of the ignition spark to a wear volume when an ignition spark is generated, is increased in such a way that an enlargement of the spark gap occurring as a result of wear when an ignition spark is generated is minimized.

Abstract: A barrier discharge ignition apparatus has a tip end exposed to a combustion chamber of an internal combustion engine and, when subjected to a high-frequency high-voltage AC burst, generates streamer discharges for igniting a fuel/air mixture in the combustion chamber. A central electrode of the apparatus, covered by a dielectric layer and coaxially enclosed in a ground electrode, extends into the combustion chamber to a greater distance than the ground electrode. An electrode portion close to the tip end of the inner periphery of the ground electrode protrudes towards the dielectric layer, for creating a localized high-density electric field. The streamer discharges thereby enter both the to combustion chamber and also a discharge chamber of the ignition apparatus.

Abstract: A spark plug including an insulator containing an Al component, in terms of oxides, 89 mass % or more and a Ti component, in terms of oxides, more than 0 mass % and 0.2 mass % or less, characterized in that the insulator is formed of an alumina-based sintered material which contains, in a grain boundary phase present between alumina crystal grains, a first crystal phase containing at least one species selected from among an La component, an Nd component, a Pr component, a Y component, an Er component, a Yb component, and an Lu component, and a second crystal phase containing at least one species of Group 2 element components, an Al component and an Si component.

Abstract: An ignition system for an internal combustion engine includes a discharge portion of the center electrode in which a part thereof is surrounded by a bottom portion and a tubular tip portion of the center dielectric, the part of the discharge portion and the tubular tip portion are projected into a combustion chamber of the internal combustion engine from a substantially annular tip portion of the ground electrode that opens to the combustion chamber at a distal end of the ground electrode, a diameter-changing portion formed by reducing a diameter of a part of the tubular tip portion in a radial direction gradually as approaching toward a tip thereof, and a thin-walled portion formed by reducing a thickness of the tip of the tubular tip portion.

Abstract: An alumina sintered body contains a main phase consisting of alumina crystal, and crystalline phases dispersed in the main phase. The crystalline phases consist of at least one selected from a group consisting of MgAl2O4, 2MgO.2Al2O3.5SiO2, 2MgO.SiO2 and MgO.SiO2. The average grain size of the crystalline phases is 0.4 ?m to 5.3 ?m. In an arbitrary area having a size of 100 ?m×100 ?m in a cross-section of the alumina sintered body, the number of the crystalline phases having grain sizes 1 ?m to 5 ?m is 8 to 412.

Abstract: A spark plug having a metal shell, center electrode and a ground electrode. The ground electrode includes an electrode base portion extending from a front end portion of the metal shell toward the front, a bent portion connected at one end thereof to a front end of the electrode base portion and an electrode distal end portion extending from the other end of the bent portion and forming a spark discharge gap with a center electrode. The ground electrode has a base material and a coating layer applied to the base material. The coating layer is formed on at least a front end face and an outer circumferential surface other than a center-electrode-side surface of the electrode distal end portion of the ground electrode. The base material of the ground electrode is exposed at least at a part of the electrode base portion.

Abstract: A plasma ignition plug for an internal combustion engine has a thorium alloyed tungsten anode separated from a vanadium- or beryllium-alloyed copper cathode by a boron nitride ceramic powder insulator. A generally semi-spherical titanium emitter is electrically coupled to the anode and disposed within an end of the insulator so as to form an annular gap with a torus on the end of the cathode. The surface of the emitter protrudes slightly beyond the rim of the torus on the cathode. High amplitude pulses driven into the anode arc across the annular gap to the cathode at more than twenty-four spots simultaneously, generating a plasma ignition front.

Abstract: A spark plug including: a central electrode including an upper end and a lower end; an insulating part including an upper portion and a lower portion and surrounds the central electrode so that the lower end of the central electrode extends beyond the lower portion of the insulating part; and a cap including an upper portion and a lower portion that has an end section and that surrounds the insulating part so that the lower portion of the insulating part extends beyond the lower portion of the cap. The insulating part includes an annular groove, on the external periphery thereof, on the lower end of the cap, and the lower end section of the cap is placed in the groove.

Abstract: A spark plug includes an insulator, a terminal electrode, a center electrode, a resistor, and a glass seal layer. The terminal electrode has: a recess part opened to the front end side and having a depth in a center axis direction of the terminal electrode; and a flat part neighboring the recess part at its outer circumference side. The relationship 0.52?B/A?0.91 is satisfied, wherein A (mm2) represents an area of a region surrounded by an outline of an outer circumference surface of the terminal electrode, and B (mm2) which represents an area of a region of the terminal electrode surrounded by an outline of an inner surface of the recess part, in a cross section orthogonal to the center axis and located 0.1 mm away from a front end along the center axis to the rear end side.

Abstract: A spark plug includes an insulator, a terminal electrode, a center electrode, a resistor, and a glass seal layer. The terminal electrode has: a recess part opened to the front end side and having a depth in a center axis direction of the terminal electrode; and a flat part neighboring the recess part at its outer circumference side. The relationship 0.52?B/A?0.91 is satisfied, wherein A (mm2) represents an area of a region surrounded by an outline of an outer circumference surface of the terminal electrode, and B (mm2) which represents an area of a region of the terminal electrode surrounded by an outline of an inner surface of the recess part, in a cross section orthogonal to the center axis and located 0.1 mm away from a front end along the center axis to the rear end side.

Abstract: The invention relates to an HF ignition device for igniting a fuel in an internal combustion engine with a corona discharge, comprising an ignition electrode, an insulating body on which the ignition electrode is mounted, the insulating body having a continuous channel in which an inner conductor leading to the ignition electrode is disposed, and an outer conductor which encloses the insulating body and, in combination with a section of the inner conductor, forms a capacitor, wherein the channel is filled with an electrically conductive filling material which encloses at least one conductor piece that forms at least one section of the inner conductor.

Abstract: A spark plug includes an insulator formed of a ceramic material. The ceramic material comprises Al2O3 in an amount of 98.00 wt % to 99.50 wt %; Group 2 oxides in an amount of 0.16 wt % to 0.70 wt %; SiO2 in an amount of 0.25 wt % to 0.75 wt %, Group 4 oxides in an amount of 0.01 wt % to 0.16 wt %, Group 1 oxides in an amount less than 0.0060 wt %, and P2O5 in an amount of less than 0.0040 wt %. The Al2O3 is formed of particles having a D50 median particle size by volume of 1.2 ?m to 1.8 ?m. The ceramic material is pressed, sintered, and formed to a predetermined shape. The sintered ceramic material includes a glass phase comprising the Al2O3, Group 2 oxides, and SiO2. The sintered ceramic material also includes secondary crystals of calcium hexa-aluminate (CaAl12O19) spinel (MgAl2O4), anorthite (CaAl2Si2O8), and mullite (Al6Si2O13).

Abstract: This invention relates to a corona discharge ignitor used to ignite air/fuel mixtures in automotive applications and the like. To suppress an arc from forming when a voltage is applied to the ignitor, the corona discharge ignitor has various shapes and configurations, such as angular depressions or grooves, at the tip of the insulator. The shape and configuration of the tip provides a smaller radius which creates a more intensified electric field and provides better combustion.

Abstract: An alumina sintered body comprises alumina crystals as a main phase and a grain boundary phase made up of crystalline Y2Si2O7 and amorphous SiO2 at grain boundaries of the alumina crystals wherein when the alumina sintered body is taken as 100 wt %, the high melting phase is present in the range of from 0.1 wt % to 15 wt %. There is also provided a method for preparing the alumina sintered body, which method comprising a first mixing step P1 of mixing, at least, a yttria powder having an average particle size of 60 to 100 nm and a silica powder having a given average particle size to provide a mixed slurry and a second mixing step of further mixing an alumina powder having an average particle size of 0.5 to 1.0 ?m in the mixed slurry.

Abstract: An ignition device having an electrode structure including an anode, a cathode, an auxiliary electrode, an anode coating, an auxiliary electrode coating, and an anode supporting body. A coated surface of the anode is opposed to a coated surface of the auxiliary electrode with the anode coating, a combustion space, and the auxiliary electrode coating therebetween. An exposed surface of the anode is opposed to an exposed surface of the cathode with the combustion space therebetween. A distance D1 from the coated surface of the anode to the coated surface of the auxiliary electrode via the anode coating, the combustion space, and the auxiliary electrode coating is shorter than a distance D2 from the exposed surface of the anode to the exposed surface of the cathode via the combustion space (D1<D2). A combustion bomb may be used as the cathode.

Abstract: A spark plug having sufficient durability for an internal combustion engine can restrain a sharp increase in resistance of a resistor in spite of its reduced size. The spark plug comprises an insulator having an axial hole, a metallic shell provided on the outer circumference of the insulator, a center electrode inserted into a front end portion of the axial hole, a terminal electrode inserted into a rear end portion of the axial hole, and a ground electrode. A circular columnar resistor is disposed within the axial hole between the center electrode and the terminal electrode, thereby electrically connecting the center electrode and the terminal electrode. The resistor is composed of carbon black that serves as a conductive material, a glass powder, and ceramic particles. Each of the ceramic particles has a maximum particle size of 0.5 ?m or less.

Abstract: A spark plug is such that a front end portion of an insulating member projects 2 mm or larger from a front end face of a metal shell and a volume of a portion of the insulating member which lies within a range from a front end of the insulating member to a position lying 1 mm towards a rear end side from the front end is 11 mm3 or smaller.

Abstract: Method for manufacturing a high-energy, low-voltage ignition plug comprising a ceramic material between its electrodes: there is mixed, in a container containing a liquid, from 50 to 75% of a compound which is intended to form a conductive phase and from 25 to 50% of one or more materials which allow the formation of phases of yttrium garnet after thermal processing; operations are carried out for pulverizing, drying and sieving the admixture; the admixture is pressed or injected into a mould; sintering is carried out so as to obtain a ceramic material having porosity of between 0 and 30%; the ceramic material is used in order to constitute the material located between the electrodes of a high-energy, low-voltage ignition plug. Ignition plug manufactured in that manner.

Abstract: A plasma jet spark plug provides improved ignitability and durability by forming a part of a spark discharge gap outside the electric discharge space which generates plasma. An ignition system for the plasma jet spark plug is also disclosed. The plasma jet spark plug includes a center electrode, an insulator defining an axial bore which partially surrounds the center electrode, a cavity surrounded by an inner circumferential face of the axial bore which extends from an opening portion of a front end of the axial bore of the insulator and wherein a front end face of the center electrode is formed. A ground electrode is bent towards a front end portion of the insulator.

Abstract: An igniter comprises at least two conductors in the spaced-apart configuration and an electrically conductive layer bridging the at least two conductors, wherein the conductive layer has an electrical resistance greater than an electrical resistance of the at least two conductors. In one embodiment, the at least two conductors and the electrically conductive layer comprise a conductive ink, which may be the same conductive ink having different dimensions. A supplementary initiator composition may be deposited on or incorporated into the conductive layer. In a process for producing the igniter, the electrically conductive layer and the at least two conductors are printed on a non-electrically conducting substrate.

Abstract: An ignition plug is disclosed which includes a hollow main cell having a bendable extension part and a primary combustion chamber, an insulator mounted in the main cell, to insulate a terminal rod centrally embedded in the main cell, a central electrode having a first electrical contact arranged in the primary combustion chamber, the central electrode extending downwardly from the terminal rod while being surrounded by the insulator, a second electrical contact provided at a lower inner surface of the main cell while being arranged in the primary combustion chamber, the second electrical contact corresponding to the first electrical contact, and a cross flame ignition valve coupled to the main cell by the extension part in a bent state of the extension part, the cross flame ignition valve having a main ignition hole and auxiliary ignition holes for guiding flames from the primary combustion chamber to an interior of a cylinder.

Abstract: The invention relates to a plasma-generating spark plug which undergoes excitation in the radio frequency domain. The invention comprises at least one first metallic electrode (12, 14), an insulator (13), one of which is equipped with a housing (130) in which the other element (13, 14) is mounted with a gap (15, 16) therebetween. The surface of the insulator (13) opposite the first electrode (12, 14) is metallised.

Abstract: A plasma ignition system includes an ignition plug attached to an engine and a high-voltage supply. The plug includes a center electrode serving as a positive pole, a ground electrode serving as a negative pole, and an insulating member insulating the center electrode from the ground electrode and defining a discharge space therein. At least a part of a surface of the center electrode faces the space, and at least a part of a surface of the ground electrode faces the discharge space. The plug puts gas in the space into a plasma state and injects the gas into the engine as a result of application of high voltage and supply of a large current to the plug by the high-voltage supply. The center electrode has a recess portion opposed to the space and recessed in a direction opposite to an injection direction.

Abstract: A spark plug and method for making. The spark plug comprises a center electrode, an insulator surrounding the center electrode, and a metallic shell surrounding the insulator. The spark plug also includes a ground electrode engaged with the metallic shell. The ground electrode has a first surface facing the center electrode for defining a spark gap and a second surface opposite the first surface. A cross-section of the ground electrode between the first and second surfaces includes a first zone of a non-noble metallic base material extending a distance from the second surface toward the first surface and a second zone of a blend of the non-noble base material and a noble metallic material extending from the first zone to the first surface. A method of making the spark plug includes the step of disposing a quantity of noble metallic material on an electrode blank formed of a non-noble metallic base material.

Abstract: A ceramic includes alumina in an amount between about 90 and about 99% by weight, a zirconium containing compound in an amount between about 0 and about 1% by weight, and an oxide mixture in an amount between about 1 and about 10% by weight. The oxide mixture includes a glass former and a network modifier, wherein the molar ratio of the glass former to the network modifier ranges between about 0.8:1 and 1.2:1. The ceramic insulator is particularly adapted for use as an insulator in a spark plug to provide improved dielectric strength and shunt resistance of greater than one 1000 megaohms at 1000 degrees Fahrenheit, so as to reduce the shunting of the spark plug and thereby improve the quality of the spark generated by the spark plug.

Abstract: The present application is to provide a spark plug where a marking layer 2m under a glaze layer 2d can form a color stably, even if the Pb amount is decreased in the glaze layer. The glaze layer 2d is formed on an insulator 2 of the spark plug, and the marking layer 2m is formed under the glaze layer 2d. The glaze layer 2d contains, e.g., 1 to 25 mol % of a Zn component in terms of Zno and 5 mol % or lower, e.g., 1 mol % or lower of a Pb component in terms of PbO. On the other hand, the marking layer 2m is adjusted in kinds and amounts of metallic element components in such manners that a tint seen through the glaze layer 2d is 3 or lower in brightness specified by JIS:Z8721 as well as 3 or lower in chroma specified by JIS:Z8721, or 4 or lower in the brightness specified by JIS:Z8721 as well as 2 or lower in the chroma specified by JIS:Z8721.

Abstract: In a spark plug composed of a center electrode and an earth electrode, at least one of confronting portions of the center electrode and the earth electrode which are in opposed relation to each other is constructed with a noble metal chip containing Pt as a principal component. The noble metal chip is joined to an electrode base material of the center electrode or the earth electrode and is made of an alloy comprising Pt and another element. In this noble metal chip, Pt is contained as a first component, while Re is contained as a second component. The employment of this noble metal chip enables suppressing the growth of platinum balls even in a high-temperature atmosphere.

Abstract: The seal between the insulator and the center electrode is to be improved in a spark plug for an internal combustion engine comprising a shell (12), an insulator (16) located in the shell and composed of a sintered ceramic material, as well as a center electrode (18) and a terminal stud (22) that have an electrically conductive connection with each other and are located in the insulator. For this purpose, it is provided that a cermet (28) abuts the center electrode, the ceramic phase of which is composed of the same or a similar material as the insulator, and the metallic phase of which is composed of a material having good electrical conductivity. Since the material properties of the cermet are similar to those of the insulator—the thermal expansion, in particular, is same—a particularly good seal is created between the cermet and insulating body.

Abstract: A spark plug comprising: a center electrode; a metal shell; and an alumina ceramic insulator disposed between the center electrode and the metal shell, wherein at least part of the surface of the insulator is covered with a glaze layer comprising oxides, the glaze layer comprising: 1 mol % or less of a Pb component in terms of PbO; 40 to 60 mol % of a Si component in terms of SiO2; 20 to 40 mol % of a B component in terms of B2O3; 0.5 to 25 mol % of a Zn component in terms of ZnO; 0.5 to 15 mol % in total of at least one of Ba and Sr components in terms of BaO and SrO, respectively; 2 to 12 mol % in total of at least one alkaline metal component of Na, K and Li, in terms of Na2O, K2O, and Li2O, respectively, wherein K is essential; and 0.

Abstract: A spark plug retains a resistor and has formed on alumina-based insulator a glaze layer, in which the glaze layer contains Pb component in a content of 1 mol % or less in terms of PbO, contains Si component, B component, Zn component, Al component, Ba component and/or Sr component, and contains F component in a content of 1 mol % or less. In addition, the glaze layer contains one kind or more of alkaline metal components, with Li component being necessary, and further contains one kind or more of phosphate ion, sulfate ion, fluoride ion and chloride ion in a content of 0.5 to 10 mol %. The glaze layer has a Vickers hardness Hv of 100 or more, shows excellent strength, especially impact resistance in spite of a reduced content of Pb component.

Abstract: A glass or glass powder is fused from a starting mixture containing approximately 38 wt % to 48 wt % SO2, 15 wt % to 19 wt % Al2O3, 4.5 wt % to 11 wt % TiO2, 0 wt % to 1.5 wt % Na2O, 0 wt % to 1.5 wt % K2O and 23 wt % to 30 wt % CaO. In addition, a glass powder mixture includes two glass powders, a carbon black powder and an organic binder, the first glass powder having a mean particle size of approximately 150 &mgr;m to 250 &mgr;m, the second glass powder having a mean particle size of less than approximately 100 &mgr;m, which may be 10 &mgr;m to 70 &mgr;m. The glass or glass powder mixture is suitable for producing a glass ceramic, such as that used as a resistor seal and/or a gas-tight glass ceramic solder in a spark plug.

Abstract: The glaze layer 2d of the spark plug 100 includes oxides of: 15 to 60 mol % of a Si component in terms of SiO2; 22 to 50 mol % of a B component in terms of B2O3; 10 to 30 mol % of a Zn component in terms of ZnO; 0.5 to 35 mol % of Ba and/or Sr components in terms of BaO or SrO; 1 mol % or less of an F component; 0.1 to 5 mol % of an Al component in terms of Al2O3; and 5 to 10 mol % in total of at least one of alkaline metal components of Na, K and Li, in terms of Na2O, K2O, and Li2, respectively, wherein Li is essential, and the amount of the Li component is 1.1 to 6 mol % in terms of Li2O.

Abstract: An insulator for spark plug comprises an alumina-based sintered body comprising: Al2O3 as a main component; and at least one component (hereinafter referred to as “&bgr; component”) selected from the group consisting of Ca component, Sr component and Ba component, wherein the alumina-based sintered body comprises particles comprising a compound comprising the &bgr; component and Al component, the compound having a molar ratio of the Al component to the &bgr; component of 4.5 to 6.7 as calculated in terms of oxides thereof, and has a relative density of 90% or more.

Abstract: A contact glass composition for use in resistor-type spark plugs is described. The contact glass composition is a mixture of: (a) at least one metal; (b) graphite; and (c) silicon. Additionally, borosilicate glass, barium borate glass, magnesium aluminum silicate, ball clay, and aluminum may also be included in the contact glass composition.

Abstract: An igniter for a combustor of a gas turbine comprises a ground shell electrical conductor which provides the electrical ground path back to the spark source. The spark source connects to the conductor and a ground return path connects to the ground shell. Multiple ignition spark source electrical conductors are used in the single igniter. At least one insulator isolates the spark sources from each other and from the ground shell conductor. An electrical connection, typically a connector that would mate with an ignition source electrical lead having a source conductor, a ground conductor, and insulation to separate these conductors, mates with a spark source to operate the igniter.

Abstract: A spark plug for an internal combustion engine comprises a tubular metal ground shell, a first electrode passing through the interior of the shell, a ceramic insulator sealing the space between the shell and the first electrode and a second electrode extending from the shell to define a gap with the first electrode. The ratio of effective distance along the surface of the ceramic defining the potential surface discharge path to the distance between the first and second electrodes being selected to prevent surface discharge as the spark gap erodes.

Abstract: An igniter plug is disclosed for use in jet and other internal combustion engines. The igniter plug has a center electrode having a firing tip, which is mounted within an insulator which in turn is mounted within an exterior metal shell. A ground electrode is integral with or in electrical contact relationship with the metal shell and is disposed in a spaced, spark gap relation with the firing tip of the center electrode. An electrically semiconducting surface is disposed adjacent the spark gap and in electrical contact with the center electrode and with the ground electrode. The electrically semiconducting surface is formed by a sintered ceramic body having an actual density of more than 95 percent of its theoretical maximum density, and consists essentially of 67-80 wt % of silicon carbide particles and 20-33 percent by weight of grain boundary phase of alumina particles, as well as one or more sintering aids selected from magnesia, silica or calcia.

Abstract: A spark plug in use for an internal combustion engine, includes an insulator placed in a metal shell in a manner to extend its front end beyond the metal shell, a center electrode is placed within an axial bore provided by the insulator, an outer electrode which is welded to a front end of the metal shell is so bent that a firing end of the outer electrode faces a front end of the insulator with a space therebetween to cause surface-spark discharges along a front end surface of the insulator and to cause a semi-surface spark discharge between the center electrode and the outer electrode, the front end of the center electrode is protroacted from a front end of the insulator by at most than 0.5 mm or retracted from the front end of the insulator by at most than 1.0 mm, and the firing end of the outer electrode is in line with the front end surface of the insulator, thereby optimizing a carbon-deposit cleaning performance of the spark plug with the semi-surface spark discharge, according to the invention.

Abstract: In a spark plug insulator made of a sintered ceramic body, including aluminum nitride (AlN) or aluminum oxynitride (AlON) ceramic powder having an average grain size of 1.5 .mu.m in which the oxygen content of the aluminum nitride or the aluminum oxynitride powder is less than 2 percent by weight. Magnesium (Mg) is also present in an amount in the range from 0.01 wt. % to 5.0 wt. % where the amount of the magnesium (Mg) is calculated by converting the magnesium (Mg) to its oxidized compound (MgO). Also included is a sintering additive present in an amount up to 10 wt. % selected from the group consisting of rare earth metal compounds in which the weight percentage of the sintering additive is calculated by converting the sintering additive to its oxidized compound. The rare earth metal compound is selected from the group of yttrium oxide (Y.sub.2 O.sub.3) calcium oxide (CaO), barium oxide (BaO), strontium oxide (SrO), scandium oxide (Sc.sub.2 O.sub.2), europium oxide (Eu.sub.2 O.sub.

Abstract: A spark plug for igniting fuel/air mixtures in internal combustion engines, in particular in internal combustion engines of motor vehicles. On its insulating-body foot, the spark plug has a coating which is intended to protect against misfirings and cold-starting difficulties as a consequence of electrically conductive deposits, in particular in the case of installation of spark plugs in new motor vehicles. The coating includes solvent-free silicone rubber or silicone resin. The silicone rubber may contain filler and is provided with silicone oil for the purpose of good processability. Expediently, the inner side of the metal housing which is exposed to the combustion chamber is also covered with the coating. The coating is physiologically safe, environmentally acceptable and resistant to handling, and does not require expensive extraction systems if it is sprayed onto the appropriate region of the spark plug by means of nozzles.

Abstract: A compact fluorescent lamp having a lamp envelope with a plurality of lamp ends disposed within a housing or base configuration, utilizes an enhanced adhesive material for securing the lamp envelope to the housing or base that is reflective. The adhesive material has a reflective material added thereto that allows for the light typically absorbed or otherwise lost in the housing, to be reflected back out thereby improving the luminous efficiency of such lamp. The adhesive material is also effective for blocking UV radiation from entering the area in which electronic components of the ballast circuit may be disposed.