公开(公告)号：US20240396309A1

公开(公告)日：2024-11-28

申请号：US18669762

申请日：2024-05-21

Applicant: Niterra Co., Ltd.

Inventor： Tatsuya GOZAWA

IPC: H01T13/34

Abstract: A spark plug includes: a cylindrical center electrode extending along an axial line; a metal shell that holds the center electrode in an insulated manner; and a ground electrode electrically connected to the metal shell. A spark gap is formed between a side surface of the center electrode and an end face of the ground electrode. The metal shell includes a tubular distal end portion inside which the spark gap is located. In a cross section perpendicular to the axial line and including a center of gravity of the end face, a distance between a center line of the ground electrode, the center line including the center of gravity, and a point of tangency of a tangent line to the side surface of the center electrode is greater than 0 and smaller than a distance between an edge of the end face and the center of gravity.

公开(公告)号：US20240063609A1

公开(公告)日：2024-02-22

申请号：US18265869

申请日：2021-10-11

Applicant: Niterra Co., Ltd.

Inventor： Tatsuya GOZAWA ,  Ritsuka NAKAGAWA

IPC: H01T13/32 ,  H01T13/08 ,  H01T13/46 ,  H01T13/54 ,  H01T13/34

CPC classification number: H01T13/32 ,  H01T13/08 ,  H01T13/467 ,  H01T13/54 ,  H01T13/34

Abstract: Provided is a spark plug with which pre-ignition of fuel gas that has flowed into an auxiliary chamber can be reduced. The spark plug is provided with: an insulator (11); a central electrode (14) disposed in the insulator; a main metal fitting (20) in which a shelf portion (23) for locking the insulator is provided; a grounding electrode (30) between the central electrode and which a spark gap (32) is provided; and a cap (40) joined to the main metal fitting by way of a melted portion (41). The cap forms an auxiliary chamber (42), and includes an injection port (45) penetrating from an inner surface (43) to an outer surface (44). There is a gap (47) extending from the auxiliary chamber to the melted portion, between a first surface (26) connecting an inner peripheral surface of the main metal fitting and an outer peripheral surface of the main metal fitting on a tip end side of the shelf portion, and a second surface (46) of the cap, connecting an inner surface and an outer surface thereof, and the gap includes an opening portion (48) which opens into the auxiliary chamber in a radial direction.

公开(公告)号：US20240243556A1

公开(公告)日：2024-07-18

申请号：US18559754

申请日：2022-06-06

Applicant: Niterra Co., Ltd.

Inventor： Susumu IMAI ,  Tatsuya GOZAWA

IPC: H01T13/34

CPC classification number: H01T13/34

Abstract: A spark plug includes an insulator having an axial hole, a center electrode disposed in the axial hole and having a forward end portion projecting to a forward end of the axial hole, a tubular metallic shell which holds the insulator on its inner circumference and has a screw portion formed on its outer circumferential surface, and a ground electrode whose first end portion is inserted into a through hole provided in the metallic shell and is welded to the through hole and whose second end portion forms a discharge gap between the second end portion and the forward end portion. The screw portion has a first screw portion located on a rear end of the through hole and a second screw portion located on a forward end of the through hole, and the second screw portion has a pitch diameter larger than that of the first screw portion.

公开(公告)号：US20240250507A1

公开(公告)日：2024-07-25

申请号：US18559762

申请日：2022-06-06

Applicant: Niterra Co., Ltd.

Inventor： Susumu IMAI ,  Tatsuya GOZAWA

IPC: H01T13/08

CPC classification number: H01T13/08

Abstract: A spark plug includes an insulator having an axial hole, a center electrode disposed in the axial hole and having a forward end portion projecting to a forward end of the axial hole, a tubular metallic shell which holds the insulator on its inner circumference and has a screw portion formed on its outer circumferential surface, and a ground electrode whose first end portion is fixed to a through hole provided in the metallic shell and whose second end portion forms a discharge gap between the second end portion and the forward end portion. The screw portion has a first screw portion located on a rear end of the through hole and a second screw portion located on a forward end of the through hole, and the first screw portion has a pitch diameter larger than that of the second screw portion.

公开(公告)号：US20240396308A1

公开(公告)日：2024-11-28

申请号：US18669682

申请日：2024-05-21

Applicant: Niterra Co., Ltd.

Inventor： Tatsuya GOZAWA

IPC: H01T13/16 ,  H01T13/34

Abstract: A spark plug includes: a center electrode; a metal shell that holds the center electrode in an insulated manner; and a rod-like ground electrode electrically connected to the metal shell and having one end opposed to the center electrode. The metal shell includes a tubular distal end portion inside which the one end of the ground electrode is located. The distal end portion has a hole into which the other end of the ground electrode is inserted. A value obtained by dividing a surface area of a portion of the ground electrode, the portion being located on an inner circumferential side of the distal end portion, by a side surface area of a portion of the ground electrode, the portion being located inside the hole, is less than or equal to 13.1.