公开(公告)号：US12249808B2

公开(公告)日：2025-03-11

申请号：US18686680

申请日：2022-08-29

Applicant: NITERRA CO., LTD.

Inventor： Yuki Yoshida ,  Naoki Nishio

IPC: H01T13/06

Abstract: A spark plug which can increase the reactive force of a shelf part. The spark plug includes a cylindrical metal shell provided around an outer periphery of an insulator. The metal shell includes, on an inner periphery of the metal shell, a proximally oriented surface in contact with the insulator, a distally oriented surface located on the distal side relative to the proximally oriented surface, a first surface extending from the distally oriented surface toward the distal side; and a second surface extending from the proximally oriented surface toward the proximal side. In a section containing an axial line, angle A formed between the distally oriented surface and the first surface and angle B formed between the proximally oriented surface and the second surface have a relationship A≤1.15B, with angle A being greater than or equal to 90° and angle B being greater than or equal to 90°.