Spark plug
AssigneeNgk Spark Plug Co., Ltd.
InventorJunji Kimura
Life of this patent
Estimating the term…
Abstract
A spark plug includes a tip extending in a first direction and an electrode base metal having an extending portion extending in the first direction and connected to the tip through a fusion zone. In a section taken along the first direction and containing a center axis of the tip, in a case where two ends of the interface between the extending portion and the fusion zone are located at the same position with respect to the first direction, the linear distance between the ends is denoted by A, or, in a case where one end is located forward of the other end, the distance from the one end to an intersection between a straight line passing the one end and extending perpendicularly to the center axis and the outline of the fusion zone is denoted by A. The interface length B satisfies a relational expression B/A≥1.2.
Claims8
A spark plug comprising:
- a tip extending in a first direction directed from a rear end side to a forward end side;
- and
- an electrode base metal having an extending portion which extends in the first direction and whose forward end portion is connected to a rear end portion of the tip through a fusion zone,
- wherein, in a section taken along the first direction and containing a center axis of the tip extending in the first direction,
- A and B satisfy a relational expression B/A≥1.2,
- where, in a case where two ends of a line indicative of an interface between the extending portion and the fusion zone are located at the same position with respect to the first direction, A is a linear distance between the two ends, or,
- in a case where one of the two ends is located forward of the other end with respect to the first direction, A is a distance on a straight line passing the one end and extending perpendicularly to the center axis, from the one end to an intersection between the straight line and an outline of the fusion zone on a side toward the other end, and
- B is a length of the line indicative of the interface.
Dependencies are inferred from the claim text.