Back to results
US 10,992,112 B2Granted
Fouling resistant spark plugs
AssigneeFram Group IP LLC
InventorsJing Zheng, Ronald P. Rohrbach, Peter D. Unger, Jeffrey T. Boehler
Life of this patent
Estimating the term…
Abstract
A spark plug includes an insulative sleeve. A glaze coating is disposed on an exterior surface of the insulative sleeve. The glaze coating includes a boric acid, a borosilicate glass, a barium borate glass, a phosphorous glass, a silicate glass, or a combination thereof. The glasses are independently modified with a modifier selected from the group consisting of alkali group metals, alkali earth group metals, aluminum, silicon, a halogen, or a combination thereof. The glaze coating has a softening point between about 650° C. and about 1100° C.
Claims14
A spark plug comprising
- an insulative sleeve having a central axial bore and an exterior surface that is substantially parallel to the central axial bore, wherein a glaze coating is disposed on the exterior surface, wherein the glaze coating is a continuous band located about 0.1 to about 5 millimeters from a top edge of the insulative sleeve, the band having a width of about 1 to about 20 mm, wherein the glaze coating has a softening point between about 650° C. and about 1100° C., wherein the glaze coating is located at a constant distance from about 1 mm to about 3 mm away from the central axial bore, and wherein the glaze coating comprises (a) a barium borate glass material with a respective first modifier selected from the group consisting of an alkali group metal, an alkali earth group metal, aluminum, silicon, a halogen, and a combination thereof, and (b) a high temperature silicate glass material with a respective second modifier selected from the group consisting of an alkali earth group metal, aluminum, and a combination thereof;
- a center electrode extending through the central axial bore of the insulative sleeve and having a firing tip that extends beyond the top edge of the insulative sleeve;
- a metal shell, wherein the insulative sleeve is positioned within and secured to the metal shell;
- and
- a ground electrode supported by the metal shell and positioned in a spaced relationship relative to the center electrode so as to generate a spark gap.
2 more elements
A spark plug comprising
- an insulative sleeve having a central axial bore and an exterior surface that is substantially parallel to the central axial bore, wherein a glaze coating is disposed on the exterior surface, wherein the glaze coating is a continuous band located about 0.1 to about 5 millimeters from a top edge of the insulative sleeve, the band having a width of about 1 to about 20 mm, wherein the glaze coating has a softening point between about 650° C. and about 1000° C., wherein the glaze coating has a thickness of about 100 to about 400 micrometers, wherein the glaze coating is located at a constant distance from about 1 mm to about 3 mm away from the central axial bore, and wherein the glaze coating comprises (a) a barium borate glass material with a first modifier selected from the group consisting of alumina, silica, CaO, SrO, BaO, Na2O, MgO, Cl, and a combination thereof, and (b) a high temperature silicate glass material with a second modifier selected from the group consisting of an alkali earth group metal, aluminum, and a combination thereof;
- a center electrode extending through the central axial bore of the insulative sleeve and having a firing tip that extends beyond the top edge of the insulative sleeve;
- a metal shell, wherein the insulative sleeve is positioned within and secured to the metal shell;
- and
- a ground electrode supported by the metal shell and positioned in a spaced relationship relative to the center electrode so as to generate a spark gap.
2 more elements
Dependencies are inferred from the claim text.