Fouling resistant spark plug
An insulator for a spark plug is provided having an insulator tip. The insulator tip includes a feature extending radially inward from an exterior surface of the insulator tip.
1. An insulator for a spark plug comprising:
an insulator tip; and,
a circumferential feature extending radially inward from an exterior surface of the insulator tip, wherein the circumferential feature is a groove that has a diameter that is less than a diameter of the exterior surface of the insulator tip.
2. The insulator according to claim 1 , wherein the groove is a continuous annular groove formed about an entire circumference of the insulator tip.
3. The insulator according to claim 1 , wherein the groove is a discontinuous groove formed in a circumference of the insulator tip.
4. The insulator according to claim 2 , wherein the groove forms a pair of parallel conical surfaces connected by a semi-circular surface.
5. The insulator according to claim 1 , wherein a longitudinal length of the groove prevents foulant particles from creating an electrical short across the groove.
6. The insulator according to claim 1 , wherein an inward depth of the groove prevents foulant particles from accumulating to create a conductive surface through which an electrical charge could travel.
7. The insulator according to claim 1 , further comprising a substance located within the groove.
8. The insulator according to claim 7 , wherein the substance is a fluid or glaze capable of absorbing combustion particles.
9. The insulator according to claim 7 , wherein the substance is nonconductive or does not exceed a maximum conductivity.
10. A spark plug comprising:
a center electrode;
an insulator disposed about the center electrode;
an outer shell surrounding the insulator; and
wherein the insulator includes a tip that extends beyond an end portion of the outer shell and wherein a circumferential feature is formed in an exterior surface of the insulator tip and is a groove in the insulator tip.
11. The spark plug according to claim 10 , wherein the groove is a continuous annular groove formed about an entire circumference of the insulator tip.
12. The insulator according to claim 10 , wherein the groove is a discontinuous groove formed in a circumference of the insulator tip.
13. The spark plug according to claim 11 , wherein the groove forms a pair of parallel conical surfaces connected by a semi-circular surface.
14. The spark plug according to claim 10 , wherein a longitudinal length of the groove prevents foulant particles from creating an electrical short across the groove.
15. The spark plug according to claim 10 , wherein an inward depth of the groove prevents foulant particles from accumulating to create a conductive surface.
16. The spark plug according to claim 10 , further comprising a substance located within the groove.
17. The spark plug according to claim 16 , wherein the substance is a fluid or glaze capable of absorbing combustion particles.
18. The insulator according to claim 16 , wherein the substance is nonconductive or does not exceed a maximum conductivity.
19. The insulator according to claim 1 , wherein the groove has a triangular cross-sectional shape.
20. The insulator according to claim 1 , wherein the groove has a rounded cross-sectional shape.