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公开(公告)号:US10312669B2
公开(公告)日:2019-06-04
申请号:US16072425
申请日:2016-10-17
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Daisuke Sumoyama , Tatsuya Gozawa , Tsutomu Shibata
Abstract: An electrode base material of the spark plug contains not less than 50 wt. % of Ni. A discharge member contains not less than 45 wt. % of Pt, and at least one of Ni and Rh. An intermediate member contains Pt and Ni. In the discharge member, a content of Pt is highest, and a total content of Pt, Rh, and Ni is not less than 92 wt. %. In the intermediate member, a content of one of Pt and Ni is not less than 50 wt. %, a content of Ni is higher than a content of Ni in the discharge member, and a total content of Pt, Rh, and Ni is not less than 85 wt. %. A thickness of the diffusion layer formed between the discharge member and the intermediate member is not less than 0.002 mm and not more than 0.065 mm.
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公开(公告)号:US10186845B2
公开(公告)日:2019-01-22
申请号:US15315105
申请日:2015-05-26
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Daisuke Sumoyama , Tatsuya Gozawa , Magoki Shimadate , Yusuke Kawashima
Abstract: An electrode tip for a spark plug, wherein Pt is contained as a main component, 7% by mass or more of Rh is contained, and a total content of Pt and Rh is greater than or equal to 95% by mass. The electrode tip includes: a narrow portion having the same cross-sectional shape in a direction of an axis; and a wide portion which is adjacent to the narrow portion and has a cross-sectional area, in a radial direction, which is greater than the narrow portion.
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公开(公告)号:US09705292B2
公开(公告)日:2017-07-11
申请号:US15245583
申请日:2016-08-24
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa , Daisuke Sumoyama , Tsutomu Shibata
Abstract: A spark plug comprising a center electrode, a ground electrode disposed on the center electrode across a gap, and a tip joined to an opposed surface of the ground electrode that is opposed to the center electrode, the tip has a discharge layer and a relieving layer, the relieving layer is formed from a Pt—Ni alloy and joined to the opposed surface via a diffusion layer, the discharge layer is formed from a Pt—Rh alloy and joined via a clad diffusion layer to a side of the relieving layer opposite to a side of the relieving layer at which the ground electrode is joined, and 0.81≦A/B≦1.21 is satisfied when an average cross-sectional area of the discharge layer is A mm2 and an average cross-sectional area of the relieving layer is B mm2, and a method for producing the spark plug.
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公开(公告)号:US10910796B2
公开(公告)日:2021-02-02
申请号:US16868852
申请日:2020-05-07
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa
Abstract: A spark plug includes: a center electrode; a ground electrode that is provided such that a gap for spark discharge is formed between the center electrode and the ground electrode; and a plug cover covering the center electrode and the ground electrode from a front side to form an auxiliary chamber, the plug cover being provided with a through hole, wherein 60% or more of the auxiliary chamber is present in a sphere. The sphere t has a center at a midpoint of a line segment connecting the center electrode and the ground electrode at a shortest distance on an axial line of the center electrode and is in contact with a point located closest from the center on an inner open end of the through hole is imagined.
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公开(公告)号:US10742002B1
公开(公告)日:2020-08-11
申请号:US16837495
申请日:2020-04-01
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa , Daiki Goto
IPC: H01T13/02
Abstract: A spark plug wherein the occurrence of pre-ignition and misfires in the spark plug are suppressed. The spark plug includes a cover portion, that covers a front end portion of a center electrode and a facing portion of a ground electrode from a front end side of the spark plug to form a pre-chamber space. The cover portion has injection holes that are through-holes. A metal shell volume A (mm3) of a portion of the metal shell on the front side with respect to a rear end of the pre-chamber space and a thermal conductivity B (W/mK) of the metal shell at the normal temperature satisfy a formula (1): 3.6
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公开(公告)号:US10714904B2
公开(公告)日:2020-07-14
申请号:US16549250
申请日:2019-08-23
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa
Abstract: A spark plug includes: an insulator with an axial hole; a center electrode held in a front end side of the axial hole; a cylindrical metal shell disposed around the insulator and having a seal part brought into contact with an outer circumferential surface of the insulator; a ground electrode arranged to form a gap with the center electrode; and a cap connected to a front end part of the metal shell to define therein an auxiliary combustion space in which the gap is formed, the cap having at least one through hole formed to provide communication between the auxiliary combustion space and the outside, wherein the condition (B/A)≤0.25 is satisfied where A represents a volume of an imaginary space defined at a position frontward of the seal part; and B represents a volume of parts of the ground and center electrodes located in the imaginary space.
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公开(公告)号:US11431155B2
公开(公告)日:2022-08-30
申请号:US17283203
申请日:2020-06-23
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Kenji Ban , Tatsuya Gozawa
IPC: H01T13/54
Abstract: A spark plug includes a metal shell and a cap member joined to the metal shell to define a pre-chamber. The cap member includes an overlapping surface that overlaps the metal shell along the axial line direction, an inner facing surface positioned closer to the pre-chamber than is the overlapping surface, the inner facing surface facing the metal shell in the axial line direction, and an outer facing surface positioned closer to an outer periphery than is the overlapping surface, the outer facing surface facing the metal shell in the axial line direction. A portion of the cap member that is closer to the pre-chamber than is the overlapping surface s spaced from the metal shell. The metal shell and the cap member are joined together at at least one of the outer facing surface and the overlapping surface.
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公开(公告)号:US11005236B2
公开(公告)日:2021-05-11
申请号:US16835488
申请日:2020-03-31
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa
Abstract: A spark plug wherein the occurrence of cracks at a joint portion between a cover portion and a metal shell in the spark plug is prevented. The spark plug includes a cylindrical metal shell that accommodates an insulator therein, and a cover portion that covers, from a front end side of the spark plug, a front end portion of a center electrode and a facing portion of a ground electrode to form a pre-chamber space. The cover portion is joined to a front end side of the metal shell and has injection holes that are through-holes. A first coefficient of thermal expansion A (10−5/K) of the material forming the cover portion at normal temperature and a second coefficient of thermal expansion B (10−5/K) of the metal shell at normal temperature satisfy a formula (1): A
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公开(公告)号:US10833486B1
公开(公告)日:2020-11-10
申请号:US16814126
申请日:2020-03-10
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa , Kenji Ban , Daiki Goto
Abstract: A spark plug having excellent ignitability including a rod-shaped center electrode; a ground electrode that includes a facing portion facing a front end portion of the center electrode and forms a discharge gap between the facing portion and the front end portion of the center electrode; an insulator; a metal shell; and a cover portion that covers, from a front end side of the spark plug, the front end portion of the center electrode and the facing portion of the ground electrode to form a pre-chamber and includes injection holes that are through holes.
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公开(公告)号:US10770868B1
公开(公告)日:2020-09-08
申请号:US16841991
申请日:2020-04-07
Applicant: NGK SPARK PLUG CO., LTD.
Inventor: Tatsuya Gozawa
Abstract: A spark plug wherein both pre-ignition and misfires are suppressed. The spark plug includes a center electrode; a ground electrode; a cylindrical insulator; a metal shell that accommodates the insulator therein; and a cover portion that covers a front end portion of the center electrode and a facing portion of the ground electrode to form a pre-chamber. The insulator includes an outer peripheral surface exposed to the pre-chamber, the cover portion includes a portion exposed to the pre-chamber, and the metal shell includes a portion exposed to the pre-chamber. When a surface area of the outer peripheral surface is a first surface area A (mm2), and a total surface area of the portion of the cover portion and the portion of the metal shell is a second surface area B (mm2), the spark plug satisfies a relational expression 1:0.10
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