Patent ID: 9450382
Filing Date: 2016-09-20
CPC Classification: B60R,F01M,F02D,F02P,H01T

Claim Text:
1. A spark plug for an internal combustion engine, comprising a center electrode; a ground electrode arranged in radial direction around the center electrode; and an annular spark gap is formed between the center electrode and the ground electrode for igniting a fuel mixture by an electric ignition spark between the center electrode and the ground electrode, wherein the ground electrode is contoured such that particles reaching a region of the ground electrode can be removed from the annular spark gap under an influence of gravitational force, wherein the ground electrode has a first portion extending in axial direction of the center electrode and a second portion extending in radial direction toward the center electrode, through-holes for the fuel mixture arranged circumferentially in the first portion that penetrate the ground electrode viewed in radial direction of the center electrode, whereby the particles reaching the region of the ground electrode are removed via the through-holes, wherein the annular spark gap is formed between the center electrode and the second portion of the ground electrode, and wherein the ground electrode is contoured at an upper surface of the second portion extending in radial direction of the center electrode such that the upper surface extends downward in a ramp-like manner with an increasing distance from the annular spark gap, and wherein a valley is formed at an upper surface of the second portion extending in radial direction of the center electrode, wherein a lower surface of the second portion opposite the upper portion is substantially planar and substantially perpendicular to the first portion, wherein the valley is formed adjacent to the through-holes for the fuel mixture that penetrate the ground electrode viewed in radial direction of the center electrode, between the through-holes and the annular spark gap at a radial distance from the through-holes and at radial distance from the annular spark gap, and wherein the radial distance from the through-holes is smaller than the radial distance from the annular spark gap.