With Specific Joint Structure Patents (Class 313/144)
  • Patent number: 10978856
    Abstract: A spark plug including a cylindrical insulator having a step portion; a center electrode provided in an axial hole of the insulator; and a cylindrical metal shell having a ledge portion, the metal shell holding the insulator from an outer circumferential side in a state in which the step portion is engaged with the ledge portion via a packing, wherein a recess is formed on a part contacting with the packing, of one of the step portion and the ledge portion, and a projection which at least partially overlaps the recess in the axial-line direction is formed on a part contacting with the packing, of the other of the step portion and the ledge portion.
    Type: Grant
    Filed: October 12, 2020
    Date of Patent: April 13, 2021
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Yusuke Tanahashi, Naoki Nishio
  • Patent number: 10320156
    Abstract: A spark plug and a method for manufacturing a spark plug. The spark plug has a retaining mechanism holding the insulator in the body in a positive manner, by means of which the insulator is pressed against the seal seat in the longitudinal direction with a preloading force (Fv) in order to seal the passage against the flow of combustion gases through it. A positive-acting securing mechanism that at least partially overlaps the side of the retaining mechanism facing away from the front end is placed on, and attached to, the body. Provision is made so that the insulator projects beyond the side of the securing mechanism facing away from the front end, wherein the securing mechanism overlaps the retaining mechanism, forming a gap with the retaining mechanism and forming a gap with the insulator.
    Type: Grant
    Filed: August 14, 2017
    Date of Patent: June 11, 2019
    Assignee: FEDERAL-MOGUL IGNITION GMBH
    Inventors: Werner Niessner, Marko Schwesinger
  • Patent number: 10096976
    Abstract: An electrode for a spark plug, having an electrode base body and a cylindrical wear part, the wear part having a longitudinal axis that extends from an end face of the wear part, facing the electrode base body, to an end face situated opposite this end face, and the wear part having a first region and a second region, the wear part not being fused in the first region and the wear part being fused in the second region.
    Type: Grant
    Filed: October 9, 2015
    Date of Patent: October 9, 2018
    Assignee: ROBERT BOSCH GMBH
    Inventors: Andreas Benz, Sabine Blankl
  • Patent number: 9455553
    Abstract: A spark plug includes a metal shell formed with a mounting male thread portion and a radially outwardly protruding seat portion and a solid annular gasket disposed between the male thread portion and the seat portion. The gasket has a recessed portion formed with a depth in the direction of an axis such that the recessed portion has an opening at a front end surface of the gasket (18) located opposite to the seat portion. The front end surface of the gasket includes an inner peripheral front end surface region decreasing in thickness toward an inner periphery of the gasket and an outer peripheral front end surface region formed radially outside the inner peripheral front end surface region. The opening of the recessed portion is located radially inside an innermost periphery of the outer peripheral front end surface region.
    Type: Grant
    Filed: February 12, 2014
    Date of Patent: September 27, 2016
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Takuya Shimamura, Jiro Kyuno
  • Patent number: 9368943
    Abstract: A spark plug having a metal shell, an insulator, a center electrode, a ground electrode, and a multi-layer sparking component. The multi-layer sparking component is attached at a firing end of the ground electrode and includes a thin precious metal layer formed overtop a base metal layer and, according to some embodiments, overhangs the end of the ground electrode. The precious metal and base metal layers may be pre-manufactured together as a bi-metal ribbon, sheet or laminate before the multi-layer sparking component is attached to the ground electrode.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: June 14, 2016
    Assignee: FEDERAL-MOGUL IGNITION COMPANY
    Inventors: Kevin J. Kowalski, Frederick J. Quitmeyer, Nathan A. Thomson, Curtis W. Verhoff, Richard L. Keller
  • Patent number: 9041275
    Abstract: In a spark plug, a center electrode includes a base member and a discharge chip that has a higher melting point than the base member. The base member and the discharge chip are joined to each other by both a weld and a diffusion layer. The weld is formed, by fusion welding, along an outer periphery of an interface between the base member and the discharge chip into an annular shape. The weld is made up of those parts of the base member and the discharge chip which are molten and mixed together during the fusion welding and solidified after the fusion welding. The diffusion layer is formed radially inside the annular weld. The diffusion layer is made up of those parts of the base member and the discharge chip which are diffused into each other across the interface between the base member and the discharge chip.
    Type: Grant
    Filed: June 9, 2014
    Date of Patent: May 26, 2015
    Assignee: DENSO CORPORATION
    Inventors: Nobuo Abe, Yuki Murayama
  • Patent number: 9000658
    Abstract: A spark plug in which a front end portion of a ground electrode is positioned outside of a virtual outer circumferential face that is formed by extending a front and outer circumferential face of a center electrode in the axis direction, and positioned on a front end side in the axis direction with respect to a virtual face including a front end face of the center electrode. Further, the equation 1.1?b/a?1.6 is satisfied, where “a” (mm) represents a first minimal distance between the front end portion of the center electrode and the front end portion of the ground electrode and, where “b” (mm) represents a second minimal distance between the front end portion of a ceramic insulator and the front end portion of the ground electrode.
    Type: Grant
    Filed: April 3, 2009
    Date of Patent: April 7, 2015
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Iwao Kunitomo, Kenji Ban
  • Patent number: 8994257
    Abstract: The spark plug has a configuration satisfying the relationships of B?0.7A and 0.3 mm?A?0.6 mm, where B is an axial thickness along the central axis line Q of the weld portion formed between the base material electrode and the noble-metal chip, and A is an axial distance along the central axis line Q between the intersection points P3 and X. The intersection point P3 is a point at which a phantom axis line radially distant from the central axis line Q by D/2 (D being a diameter of the noble-metal chip) intersects with the boundary line between the weld portion and the noble-metal chip. The intersection point X is a point at which an extension of the contour line of the base material electrode in the vicinity of the weld portion intersects with a boundary line between the weld portion and the base material electrode.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: March 31, 2015
    Assignee: Denso Corporation
    Inventors: Hiroya Ishiguro, Masaya Nakamura
  • Patent number: 8981634
    Abstract: A spark plug with a particular configuration, particularly in the area of a gasket that seals between a shell and insulator, increases the mechanical strength of the spark plug and helps prevent breaking, cracking and/or other failures in the insulator. The spark plug is designed such that the shell, insulator and gasket, which may be in the form of a sleeve-like cylindrical gasket or a ring-like annular gasket, work together to provide better support for the insulator against axial and/or radial stresses. This improved support can offset certain stresses, such as radial stress RS that can be exerted against the insulator core nose when the engine experiences knocking or misfiring.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: March 17, 2015
    Assignee: Federal-Mogul Ignition GmbH
    Inventor: Stefan Henke
  • Patent number: 8946977
    Abstract: A spark plug includes a center electrode, a ground electrode, and a tip joined to the center electrode and forming a spark discharge gap with the ground electrode. The tip is joined to the center electrode via a fusion zone, which has an exposed surface exposed to the external environment. In a section containing an axis and the center of the exposed surface, C?B?0.02 is satisfied, where C (mm) is the distance on the side surface of the tip between the fusion zone and the distal end of the tip, and B (mm) is the distance between a distal end surface of the tip and a portion of the fusion zone located closer to the axis than the side surface of the tip and located closest in the fusion zone to the distal end surface of the tip.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: February 3, 2015
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Kohei Katsuraya, Katsutoshi Nakayama
  • Patent number: 8933618
    Abstract: An electrode-attached insulator having an insulator provided with an axial hole extending in the direction of an axis and a center electrode which is disposed on a distal-end side of the axial hole and has a front end portion that is exposed from a front end of the insulator. The electrode-attached insulator includes a locking member having a collar portion which is locked on a step portion. The center electrode and the locking member are joined together in the axial hole.
    Type: Grant
    Filed: April 2, 2013
    Date of Patent: January 13, 2015
    Assignee: NGK Spark Plug Co., Ltd.
    Inventor: Yasushi Sakakura
  • Patent number: 8922103
    Abstract: A spark plug (1) includes a metallic shell (3) and a ground electrode (27) resistance-welded to the metallic shell (3). The ground electrode (27) is formed from a metal material in which precipitates PR containing at least one of an oxide, an intermetallic compound, etc., are precipitated in grain boundaries. The diameter of an equivalent circle of a precipitate PR having the greatest area is 50 ?m or less, and the shortest distance between the precipitates PR is 2 ?m or greater. The area occupied by the precipitates PR on the section of the heat-affected zone 27A is equal to 65% or more the area occupied by the precipitates PR (the diameter of an equivalent circle of a precipitate PR having the greatest area) on a section of the normal zone 27B.
    Type: Grant
    Filed: November 26, 2010
    Date of Patent: December 30, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Osamu Yoshimoto, Tomo-o Tanaka, Norihide Kachikawa
  • Publication number: 20140361679
    Abstract: In a spark plug, a center electrode includes a base member and a discharge chip that has a higher melting point than the base member. The base member and the discharge chip are joined to each other by both a weld and a diffusion layer. The weld is formed, by fusion welding, along an outer periphery of an interface between the base member and the discharge chip into an annular shape. The weld is made up of those parts of the base member and the discharge chip which are molten and mixed together during the fusion welding and solidified after the fusion welding. The diffusion layer is formed radially inside the annular weld. The diffusion layer is made up of those parts of the base member and the discharge chip which are diffused into each other across the interface between the base member and the discharge chip.
    Type: Application
    Filed: June 9, 2014
    Publication date: December 11, 2014
    Inventors: Nobuo ABE, Yuki MURAYAMA
  • Patent number: 8896193
    Abstract: A spark plug including a ceramic insulator having an axial hole, a center electrode inserted into the axial hole, a metallic shell provided around the insulator, a ground electrode fixed to the metallic shell, and a tip joined to a distal end portion of the ground electrode and forming a spark discharge gap between the tip and a forward end portion of the center electrode. The ground electrode includes an outer layer and an inner layer provided inside the outer layer and formed of a metal containing copper as a main component. The tip is joined to the ground electrode by a fusion portion containing a metal forming the tip and a metal forming the outer layer. The fusion portion is in contact with the inner layer and contains copper. The spark plug efficiently conducts heat from the tip to the inner layer to improve corrosion resistance of the tip.
    Type: Grant
    Filed: December 3, 2012
    Date of Patent: November 25, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventor: Yoshikazu Kataoka
  • Patent number: 8896194
    Abstract: A spark ignition device has a ceramic insulator surrounded by a metal shell. The metal shell extends along a longitudinal axis to a distal end. A center electrode is received in the ceramic insulator and extends along the longitudinal axis. A ground electrode has an attachment end fixed by a weld joint to the distal end of the shell and a free end extending from the distal end to provide a spark gap. The weld joint includes a capacitive pulse discharge weld joint and a laser weld joint, which in combination inhibit material expulsion; provide a reliable, strong attachment of the ground electrode to the shell; provide an improved heat transfer path between the ground electrode and the shell, and facilitate repeatable and accurate positioning of the ground electrode to the shell. The weld joint includes a homogeneous mixture of the metal shell and the ground electrode.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: November 25, 2014
    Assignee: Federal-Mogul Ignition Company
    Inventor: Frederick James Quitmeyer
  • Patent number: 8884503
    Abstract: A spark plug has a metal shell and a ground electrode joined at a base end portion thereof to the metal shell and includes a surface layer and a core higher in thermal conductivity than the surface layer. The surface layer has a thickness of 0.2 to 0.4 mm at a specific position that is located 1 mm from the base end portion. The spark plug satisfies the following condition: W1?W2×1.55?(W3+0.25) where W1 (mm) is a width of the metal shell at a weld region of the metal shell joined with the base end portion in a specific direction that extends perpendicular to the axis direction through a center line of the ground electrode; W2 (mm) is a thickness of the ground electrode at the specific position in the specific direction; and W3 (mm) is a thickness of the surface layer at the specific position in the specific direction.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: November 11, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Satoshi Nagasawa, Akira Suzuki
  • Patent number: 8878427
    Abstract: The spark plug has a configuration satisfying the relationships of B?0.7A and 0.3 mm?A?0.6 mm, where B is an axial thickness along the central axis line Q of the weld portion formed between the base material electrode and the noble-metal chip, and A is an axial distance along the central axis line Q between the intersection points P3 and X. The intersection point P3 is a point at which a phantom axis line radially distant from the central axis line Q by D/2 (D being a diameter of the noble-metal chip) intersects with the boundary line between the weld portion and the noble-metal chip. The intersection point X is a point at which an extension of the contour line of the base material electrode in the vicinity of the weld portion intersects with a boundary line between the weld portion and the base material electrode.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: November 4, 2014
    Assignee: Denso Corporation
    Inventors: Hiroya Ishiguro, Masaya Nakamura
  • Patent number: 8860292
    Abstract: A spark plug and a method of forming the same. The spark plug having a rod-shaped center electrode extending in an axial direction, a tubular insulator having an axial hole and holding the center electrode in the axial hole, a tubular metallic shell having an end surface, an inner circumferential surface, and a gap formed between the inner circumferential surface and a forward end portion of the insulator, and a ground electrode welded to the end surface. A method of manufacturing the spark plug includes a welding step of welding the ground electrode to the end surface; and a shaping step which is performed after the welding step so as to form the inner circumferential surface, through shaping, on the metallic shell having the ground electrode welded to the end surface thereof.
    Type: Grant
    Filed: February 10, 2014
    Date of Patent: October 14, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventor: Tomoki Kawai
  • Patent number: 8853930
    Abstract: An ignition plug that reliably restrains generation of corona discharge for enhancing accuracy in detection of ionic current and method of manufacturing same. The ignition plug is configured such that a metallic shell and an insulator are fixed together by means of a crimped portion provided at a rear end portion of the metallic shell and bent radially inward. An electrically insulative filling member fills a space formed between the crimped portion and the insulator. The filling member covers at least a portion of an outer circumferential surface of a rear trunk portion of the insulator along the entire circumference and the entirety of a rear end surface of the metallic shell, which is a portion of the outer surface of the crimped portion and is visible from the rear side with respect to the direction of an axial line CL1.
    Type: Grant
    Filed: January 14, 2014
    Date of Patent: October 7, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Tatsunori Yamada, Naofumi Yamamura, Kenji Ban
  • Patent number: 8791627
    Abstract: A spark plug includes an insulator, and a metal shell disposed at an outer periphery of the insulator and including a shoulder. The insulator includes a trunk portion, and a leg formed at the tip end side of the trunk portion. The shoulder of the metal shell includes a first shoulder, and a second shoulder formed at the tip end side of the first shoulder. A distance Da between the tip end of the second shoulder and the leg and a distance Db between the tip end of the trunk portion and the second shoulder satisfy a relationship of Da/Db?1.1. A distance T between the rear end of the first shoulder and the tip end of the second shoulder and a distance L between the rear end of the first shoulder and a tip end face of the metal shell satisfy a relationship of T/L?0.5.
    Type: Grant
    Filed: September 24, 2013
    Date of Patent: July 29, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Keiji Ozeki, Naoyuki Mukoyama
  • Patent number: 8766520
    Abstract: A ground electrode is provided having a ground electrode body, the ground electrode body having an anchored end and a non-anchored end opposite the anchored end. The ground electrode includes a plateau extending from a surface of the ground electrode body adjacent the non-anchored end. In illustrative embodiments, the plateau is formed by removing a portion of the ground electrode body near the non-anchored end. The plateau is configured to be exposed around its periphery. A noble metal tip is fixably attached to the plateau.
    Type: Grant
    Filed: March 4, 2013
    Date of Patent: July 1, 2014
    Assignee: Fram Group IP LLC
    Inventors: Jeffrey T. Boehler, Matthew B. Below, Jerry Williams Reeves, Jr., Ovidio Bocanegra, Jayme R. Eastman, Timothy M. Frech
  • Patent number: 8760044
    Abstract: An electrode material may be used in spark plugs and other ignition devices including industrial plugs, aviation igniters, glow plugs, or any other device that is used to ignite an air/fuel mixture in an engine. In one embodiment, the electrode material has one or both of iridium (Ir) or ruthenium (Ru), and has rhenium (Re).
    Type: Grant
    Filed: February 22, 2012
    Date of Patent: June 24, 2014
    Assignee: Federal-Mogul Ignition Company
    Inventor: Shuwei Ma
  • Patent number: 8749126
    Abstract: A corona igniter 20 includes a central electrode 34 for receiving a high radio frequency voltage from a power source and emitting a radio frequency electric field to ionize a fuel-air mixture and provide a corona discharge 22. The corona igniter 20 includes an insulator 38 extending along the central electrode 34 longitudinally past the central electrode 34 to an insulator firing end 40. The insulator firing surface 42 and the center axis A present an angle ? of not greater than 90 degrees therebetween, for example the insulator firing surface may be concave. The central electrode 34 may also include a firing tip 50, in which case the insulator firing surface 42 surrounds all sides of the firing tip 50. The geometry of the insulator firing surface 42 concentrates and directs the corona discharge 22.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: June 10, 2014
    Assignee: Federal-Mogul Ignition Company
    Inventors: Patrick Durham, James Lykowski
  • Patent number: 8729784
    Abstract: An insulator for a spark plug is provided having an insulator tip. The insulator tip includes a feature extending radially inward from an exterior surface of the insulator tip.
    Type: Grant
    Filed: February 13, 2013
    Date of Patent: May 20, 2014
    Assignee: Fram Group IP LLC
    Inventors: Ronald P. Rohrbach, Peter D. Unger, Jeffrey T. Boehler, Jing Zheng
  • Patent number: 8729785
    Abstract: A spark plug comprises an insulator and a metal shell. The insulator includes a nose length portion at the forward end, and a tapered portion, extending from the rear end of the nose length portion toward the rear end of the insulator, increased in diameter toward the rear end. The metal shell includes a shoulder portion, protruding inward and having a retaining surface by which the tapered portion is retained, and a male thread portion on the outer peripheral side of the shoulder portion, and the thread diameter of the male thread portion is set to M12 or less. When the insulator's cross-sectional area, perpendicular to an axis, passing through the boundary between the nose length section and tapered portion is B (mm2), and the metal shell's cross-sectional area, perpendicular to the axis, passing through the tip of the retaining surface is C (mm2), 2.80?C/B?3.50 is satisfied.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: May 20, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Takuya Shimamura, Jiro Kyuno
  • Publication number: 20140084776
    Abstract: A spark plug includes an insulator, and a metal shell disposed at an outer periphery of the insulator and including a shoulder. The insulator includes a trunk portion, and a leg formed at the tip end side of the trunk portion. The shoulder of the metal shell includes a first shoulder, and a second shoulder formed at the tip end side of the first shoulder. A distance Da between the tip end of the second shoulder and the leg and a distance Db between the tip end of the trunk portion and the second shoulder satisfy a relationship of Da/Db?1.1. A distance T between the rear end of the first shoulder and the tip end of the second shoulder and a distance L between the rear end of the first shoulder and a tip end face of the metal shell satisfy a relationship of T/L?0.5.
    Type: Application
    Filed: September 24, 2013
    Publication date: March 27, 2014
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Keiji Ozeki, Naoyuki Mukoyama
  • Patent number: 8672721
    Abstract: A spark-ignited, internal combustion engine ignition device to increase electrical transfer efficiency of the ignition by peaking the electrical power of the spark during the streamer phase of spark creation and improving combustion quality, incorporating an electrode design and materials to reduce electrode erosion due to high power discharge, an insulator provided with capacitive plates to peak the electrical current of the spark discharge, and concomitant methods.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: March 18, 2014
    Assignee: Enerpulse, Inc.
    Inventor: Louis S. Camilli
  • Publication number: 20140070692
    Abstract: A park plug includes a tubular insulator extending along and centered on an axis, and a tubular metal shell secured to an outer peripheral surface of the insulator by crimping, in which powder for sealing is filled between the outer peripheral surface of the insulator and an inner peripheral surface of the metal shell. A relationship between a minimum outer diameter d of the insulator and a maximum inner diameter D of the metal shell in a filling-up area where the powder is filled between the metal shell and the insulator satisfies 1.12?D/d?1.16.
    Type: Application
    Filed: September 3, 2013
    Publication date: March 13, 2014
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventor: Jiro KYUNO
  • Patent number: 8664843
    Abstract: A spark plug having an insulator with improved breakage resistance. The spark plug has a cross-section that satisfies the following relationship: 0.6 mm<=L, where “A” represents a connection point between a support portion of the insulator and an insulator trunk portion formed at a front end side with respect to the support portion, where “B” represents a position closer to the outer circumference side among the positions of (a) an innermost position of a contact portion where the support portion and a packing are in contact with each other and (b) an intersection of the support portion and a virtual straight line that is parallel to an axial line of the spark plug and extends from an innermost circumferential end of a stepped portion of a metal shell, and where “L” represents a length of a path from point “A” to point “B” along a surface of the insulator.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: March 4, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Yuichi Yamada, Hiroaki Kuki, Naomichi Miyashita, Jiro Kyuno
  • Patent number: 8664844
    Abstract: An object of the invention is to restrain separation of an electrode tip from a ground electrode or from a center electrode. A spark plug satisfies a condition 0.8?A1/A2?1.9, where, as viewed on a section which contains a center axis (O) of an electrode tip, A1 [Hv] is hardness of the electrode tip as measured outside a circle having a radius of 0.2 mm, with a boundary point (PA) on a surface of the spark plug between a fusion zone and the electrode tip serving as the center of the circle, and A2 [Hv] is hardness of the electrode tip as measured within the circle having a radius of 0.2 mm.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: March 4, 2014
    Assignee: NGK Spark Plug., Ltd.
    Inventors: Naomichi Miyashita, Mamoru Musasa
  • Publication number: 20140042893
    Abstract: A spark plug includes a tip joined to a center electrode. The coefficient of linear thermal expansion of the center electrode is greater than that of the tip. The tip has a gap-forming portion having a maximum width of 1.2 mm or greater and forming a gap in cooperation with the ground electrode and a to-be-joined portion joined to the center electrode. At a position A which is shifted 0.1 mm from the forward end of the outer surface of the fusion portion toward the forward end side, the width of the to-be-joined portion measured on the cross section is smaller than the width of the gap-forming portion. The to-be-joined portion satisfies Dtw/Dw?1.1, where Dtw represents the width of the to-be-joined portion at the position A, and Dw represents the width of the fusion portion at the forward end of the outer surface thereof.
    Type: Application
    Filed: August 2, 2013
    Publication date: February 13, 2014
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Yasushi SAKAKURA, Yukinobu HASEGAWA, Kei TAKAHASHI
  • Publication number: 20140042894
    Abstract: A spark plug having a metallic shell extending along an axis (CL1) and a solid annular gasket. The metallic shell has an externally threaded portion and a seat portion, and the gasket has an inside diameter smaller than the thread diameter of the externally threaded portion and is provided between the externally threaded portion and the seat portion. The forward end surface of the gasket has an inclined portion which inclines rearward with respect to the direction of the axis (CL1) from the radially outer side toward the raidally inner side. The thickness of the gasket along the axis (CL1) is 2.0 mm or less; the distance along the axis (CL1) between the outermost circumferential edge and the innermost circumferential edge of inclined portion is 0.02 mm to 0.12 mm; and the Vickers hardness of the gasket is 60 Hv or more.
    Type: Application
    Filed: April 9, 2012
    Publication date: February 13, 2014
    Inventors: Naomichi Miyashita, Yuuichi Nakano
  • Patent number: 8643263
    Abstract: A spark plug (20) includes an insulator seat angle (?i) of 35° to 50° and an increased insulator thickness (ti) in selected areas around the insulator seat (28). The insulator seat angle (?i) is greater than or equal to a boundary value provided by the equation: 90°?a cos [1?(R1?R2)÷(R4+R5)], and preferably not greater than 150% of the boundary value. The radii (R1, R2, R3, R4, R5) can be adjusted to maximize R4 while maintaining an acceptable R2. A gasket is compressed between the insulator (22) and shell (58), and the inner gasket thickness (tg2) is greater than or equal to 70% of the outer gasket thickness (tg1).
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: February 4, 2014
    Assignee: Federal-Mogul Corporation
    Inventor: John Antony Burrows
  • Patent number: 8633640
    Abstract: [Objective] To provide a spark plug which is configured such that an insulation member, from which a center electrode projects, is pressed frontward and held in a metallic shell, and is fixed by means of crimping the rear end of the metallic shell, and which can prevent a drop in gas tightness between the metallic shell and the insulation member due to a difference in thermal expansion therebetween. [Means for Solution] In a spark plug in which a mating shaft portion (10) of an insulation member (1) is loose-fitted into a mating hole portion (30) of a metallic shell (21), a filler (41) for maintaining gas tightness is charged between the outer circumferential surface of the mating shaft portion (10) and the inner circumferential surface of the mating hole portion (30). Despite the thermal expansion difference, the gas tightness is maintained, because the filler (41) for maintaining gas tightness is charged between the inner and outer circumferential surfaces.
    Type: Grant
    Filed: December 22, 2009
    Date of Patent: January 21, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Jiro Kyuno, Akira Suzuki, Mamoru Musasa
  • Patent number: 8629605
    Abstract: A spark plug includes a center electrode extending in an axial direction; an insulator formed externally of the outer circumference of the center electrode; a metallic shell formed externally of the outer circumference of the insulator and having a ledge which supports the insulator; and a ground electrode joined to the metallic shell. The insulator has a support portion which faces the ledge. A “frontward direction” is defined as the direction parallel to the axial direction toward a spark portion formed between the center electrode and the ground electrode. The insulator has a diameter reduction portion whose outside diameter reduces along the frontward direction from the support portion, and a diameter increase portion whose outside diameter increases along the frontward direction from the front end of the diameter reduction portion. This restrains the generation of leak current while maintaining heat resistance of the spark plug.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: January 14, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Kohei Katsuraya, Hiroyuki Kameda, Katsutoshi Nakayama
  • Patent number: 8624472
    Abstract: A ground electrode (27) and a noble-metal chip (32) are joined via a weld portion (42) formed by fusing and mixing an Ni alloy and a Pt alloy. A plurality of acicular or rhizoid microcracks (51) are formed in the weld portion (42). As viewed on a section of the weld portion (42), the average length of the microcracks is 50 ?m to 500 ?m, and the average aspect ratio (shorter dimension/longer dimension) of the microcracks is 0.05 or less. At least one of the Ni alloy used to form the ground electrode (27) and the Pt alloy used to form the noble-metal chip (32) contains as an additive at least one of elements belonging to Groups 3A and 4A of the Periodic Table and oxides of these elements.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: January 7, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventor: Osamu Yoshimoto
  • Patent number: 8624475
    Abstract: Disclosed is a spark plug having an insulator with good breakage resistance. A spark plug 1 contains a ceramic insulator 2, a plate packing 22 and a metal shell 3. The ceramic insulator 2 has, on an outer circumferential surface thereof, a step portion 14, a leg portion 13 and a curved surface portion 31 between the step portion 14 and the leg portion 13. The metal shell 3 has, on an inner circumferential surface thereof, a taper portion 21. The ceramic insulator 2 is fixed in the metal shell 3 with the step portion 14 retained on the taper portion 21 via the plate packing 22. Herein, 50% or more of an inner circumferential edge portion IP of the plate packing 22 is in contact with a part of the ceramic insulator 2 located front of a middle region CP of the curved surface portion 31.
    Type: Grant
    Filed: August 8, 2011
    Date of Patent: January 7, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Takuya Shimamura, Tomoaki Kato, Jiro Kyuno, Naomichi Miyashita
  • Publication number: 20130307403
    Abstract: A spark plug with a particular configuration, particularly in the area of a gasket that seals between a shell and insulator, increases the mechanical strength of the spark plug and helps prevent breaking, cracking and/or other failures in the insulator. The spark plug is designed such that the shell, insulator and gasket, which may be in the form of a sleeve-like cylindrical gasket or a ring-like annular gasket, work together to provide better support for the insulator against axial and/or radial stresses. This improved support can offset certain stresses, such as radial stress RS that can be exerted against the insulator core nose when the engine experiences knocking or misfiring.
    Type: Application
    Filed: May 9, 2013
    Publication date: November 21, 2013
    Inventor: Stefan Henke
  • Patent number: 8568181
    Abstract: A spark plug for an internal combustion engine, the spark plug having: an elongated center electrode having a center electrode tip at one end and a terminal proximate the other end; an insulator substantially surrounding the center electrode, the insulator having a channel formed in an exterior surface of the insulator; and an outer shell surrounding the insulator, the outer shell having a jamb nut portion and a distal end extending from the jamb nut portion, the distal end of the outer shell is aligned with the channel such that the distal end of the outer shell is received in and engages the channel of the outer shell.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: October 29, 2013
    Assignee: Fram Group IP LLC
    Inventor: Matthew Brian Below
  • Patent number: 8569940
    Abstract: A spark plug includes a metallic shell, an insulator, a center electrode body, a ground electrode body, and a ground electrode tip. In one embodiment, the ground electrode tip includes a non-precious metal piece and a precious metal piece attached to each other. The non-precious metal piece has a side surface attached to a free end surface of the ground electrode body.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: October 29, 2013
    Assignee: Federal-Mogul Ignition Company
    Inventors: Richard L. Keller, Kevin J. Kowalski
  • Patent number: 8564184
    Abstract: A spark plug that is equipped with an insulator that has a stem portion on a front end side, a center electrode, and a main metal member that retains the insulator at an engaging projection portion, wherein an inner diameter DIN of the engaging projection portion, the maximum outer diameter dOUT of the stem portion, which faces an inner circumferential surface of the engaging projection portion, its inner diameter dIN, and dielectric constant ? of the insulator satisfy the condition of “(DIN?dOUT)/2?0.40 (mm)”, “(dOUT?dIN)/2?1.65 (mm)”, and “??9.4”.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: October 22, 2013
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Hirokazu Kurono, Toshitaka Honda, Katsuya Takaoka, Hiroki Takeuchi, Kuniharu Tanaka, Takeshi Mitsuoka
  • Patent number: 8558442
    Abstract: A plasma jet ignition plug exhibiting high plasma generation efficiency while restraining occurrence of preignition. P1 represents the position of a rear end of a region of a metallic shell ledge, the region being in contact with an insulator. P2 represents the position of a rear end of a region of the insulator ledge, the region being in contact with the center electrode. Front end surfaces of the metallic shell, the insulator, and center electrode, an imaginary plane S1 which is perpendicular to the axis and contains position P1, and an imaginary plane perpendicular to the axis and contains position P2 are disposed in this order from front side to rear side along the axis. The axial distance A from the front end surface of the insulator to imaginary plane S1 and axial distance B from the imaginary plane S1 to imaginary plane S2 satisfy 0.5×A?B.
    Type: Grant
    Filed: December 1, 2011
    Date of Patent: October 15, 2013
    Assignee: NGK Spark Plug Co., Ltd.
    Inventor: Hiroyuki Kameda
  • Patent number: 8552628
    Abstract: An assembly for a spark plug, the assembly having: an insulator, the insulator having a channel formed in an exterior surface of the insulator; and a jamb nut surrounding the insulator, the jamb nut being aligned with the channel such that a distal end of the jamb nut does not contact the insulator.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: October 8, 2013
    Assignee: Fram Group IP LLC
    Inventor: Matthew B. Below
  • Patent number: 8534041
    Abstract: An apparatus and assembly for an igniter is provided. The igniter includes a shell comprising a base, a tip surface, and a sidewall extending therebetween wherein the sidewall surrounds a cavity within the shell. The igniter also includes a shell bore extending from the tip surface to the cavity and a pin embedded into the tip surface extending substantially tangentially with respect to the bore.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: September 17, 2013
    Assignee: Unison Industries, LLC
    Inventors: Brendon Francis Mee, Randal Parker Bold
  • Publication number: 20130221832
    Abstract: The spark plug has a configuration satisfying the relationships of B?0.7A and 0.3 mm?A?0.6 mm, where B is an axial thickness along the central axis line Q of the weld portion formed between the base material electrode and the noble-metal chip, and A is an axial distance along the central axis line Q between the intersection points P3 and X. The intersection point P3 is a point at which a phantom axis line radially distant from the central axis line Q by D/2 (D being a diameter of the noble-metal chip) intersects with the boundary line between the weld portion and the noble-metal chip. The intersection point X is a point at which an extension of the contour line of the base material electrode in the vicinity of the weld portion intersects with a boundary line between the weld portion and the base material electrode.
    Type: Application
    Filed: February 28, 2013
    Publication date: August 29, 2013
    Applicant: DENSO CORPORATION
    Inventor: Denso Corporation
  • Publication number: 20130221831
    Abstract: An electrode for a spark plug includes an electrode tip end. A first weld affixes at least a portion of the noble metal tip to the tip end of the electrode. The noble metal tip has a fold around its periphery. A second weld joins the fold of the noble metal tip to the tip end of the electrode and creates a seal over the first weld.
    Type: Application
    Filed: February 19, 2013
    Publication date: August 29, 2013
    Applicant: Fram Group IP LLC
    Inventor: Fram Group IP LLC
  • Patent number: 8492964
    Abstract: A spark plug including a center electrode; an insulator; and a metal shell, the metal shell including: a tool engaging section; a body section; and a groove section formed between the tool engaging section and the body section, and having bulges which bulge in an outer peripheral direction and in an inner peripheral direction. When a portion of the groove section having a largest outer diameter is a first section, a thinnest portion from the first section to the body section is a second section, and a portion having a thickness that is the same as that of the first section is a third section, a relation between a thickness A of the second section and a radius of curvature R of an outer surface of the metal shell that continues from the second section to the third section satisfies R×A?0.20 mm2.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: July 23, 2013
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Mai Nakamura, Akira Suzuki
  • Patent number: 8487520
    Abstract: A spark plug (1) including a noble metal tip joined to a ground electrode and forming a spark discharge gap in cooperation with a center electrode. A surface of the noble metal tip which forms the gap has an area of 0.9 mm2 or greater. The noble metal tip (32) is joined to the ground electrode (27) via a fusion zone (35) formed by irradiating at least one surface among a distal end surface and side surfaces of the ground electrode with a laser beam or an electron beam. Further, as viewed on a projection plane orthogonal to a center axis of the noble metal tip and on which the noble metal tip and the fusion zone are projected along the center axis, an overlapping region between the noble metal tip (32) and the fusion zone accounts for 70% or more of a projected region of the noble metal tip.
    Type: Grant
    Filed: December 3, 2010
    Date of Patent: July 16, 2013
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Nobuaki Sakayanagi, Katsutoshi Nakayama
  • Patent number: 8476816
    Abstract: A spark plug includes an inner conductor, an ignition tip connected to the inner conductor, an insulator surrounding the inner conductor and having a front end and a rear end, a spark plug body having a front end and a rear end, and at least one ground electrode connected to the front end of the spark plug body. The spark plug has a longitudinal direction extending parallel to the inner conductor. The spark plug body comprises a passage extending in the longitudinal direction and in which the insulator is disposed. A sleeve composed of metal is disposed between the insulator and the spark plug body. The sleeve is tightly connected to the insulator and the spark plug body and is referred to below as the “first sleeve”. At least one second sleeve is disposed at a distance from the first sleeve) and, in fact, between the first sleeve and the rear end of the insulator. The second sleeve is connected to the insulator and touches the spark plug body in the passage thereof.
    Type: Grant
    Filed: March 15, 2011
    Date of Patent: July 2, 2013
    Assignee: Federal-Mogul Ignition GmbH
    Inventor: Werner Niessner
  • Patent number: 8471449
    Abstract: Method for manufacturing a spark plug comprising an inner conductor, an insulator enclosing the inner conductor, a spark plug body enclosing the insulator, and two electrodes, the first electrode being a center electrode connected to the inner conductor in an electrically conductive manner, and the second electrode being a ground electrode connected to the spark plug body in an electrically conductive manner, with a separately prefabricated precious metal component positioned on one of the electrodes and connected to the electrode by way of resistance welding, and subsequently affixed by way of laser or electron beam welding, so that the precious metal component extends like a heel beyond the electrode surface next to the precious metal component. The precious metal component, a ball is shaped by stamping after resistance welding and before laser or electron beam welding, wherein at least one region of the ball protruding from the electrode surface is reshaped.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: June 25, 2013
    Assignee: Federal-Mogul Ignition GmbH
    Inventors: Werner Niessner, Christophe Houlle