The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 06, 2015
Filed:
Jun. 10, 2014
Denso Corporation, Kariya, Aichi-pref., JP;
Yuki Murayama, Toyoake, JP;
Denso Corporation, Kariya, JP;
Abstract
A spark plug for an internal-combustion engine. The spark plug includes a central electrode, an insulator that holds the central electrode inside, a housing that holds the insulator inside, a ground electrode that forms a spark gap with the central electrode. The ground electrode includes a ground base member connected to the housing, and a ground protrusion protruding from a confronting face of the ground base member confronting the central electrode. The ground protrusion has a diameter of 0.9 to 1.4 mm. The spark plug is configured to satisfy θ≧−53R+49, where R [mm] is a curvature radius of a base member corner and θ[degrees] is an angle formed by a shortest connecting line between the base member corner and a protrusion corner and a plane perpendicular to an axial direction of the ground protrusion.