Variable resistor card for a fuel level sensor
View Patent ↗A variable resistor card for a fuel level sensor includes a first wiper contact area, a first electrically conductive pathway electrically communicated to the first wiper contact area, a second wiper contact area, a second electrically conductive pathway electrically communicated to the second wiper contact area, and a nonconductive layer on at least one of the first and second electrically conductive pathways.
1. A variable resistor card for a fuel level sensor, comprising:
a first wiper contact area;
a first electrically conductive pathway electrically communicated to the first wiper contact area;
a second wiper contact area;
a second electrically conductive pathway electrically communicated to the second wiper contact area; and
a nonconductive layer covering at least a portion of at least one of the first or second electrically conductive pathways to resist current leakage between the pathways and thereby minimize electrolysis-induced corrosion.
2. The variable resistor card of claim 1 wherein the nonconductive layer is composed of a thick film insulating material.
3. The variable resistor card of claim 2 wherein the nonconductive layer is composed of a glass encapsulant.
4. The variable resistor card of claim 1 wherein at least a portion of the first electrically conductive pathway is within 2.0 mm of at least a portion of the second electrically conductive pathway.
5. The variable resistor card of claim 1 wherein at least a portion of at least one of the first or second electrically conductive pathways has a cross-sectional area of no greater than 0.5 mm 2 .
6. A variable resistor card for a fuel level sensor, comprising:
a substrate;
a first wiper contact area disposed on the substrate;
a first terminal pad disposed on the substrate;
a first electrically conductive pathway disposed on the substrate and electrically communicating the first wiper contact area to the first terminal pad;
a second wiper contact area disposed on the substrate;
a second terminal pad disposed on the substrate;
a second electrically conductive pathway disposed on the substrate and electrically communicating the second wiper contact area to the second terminal pad; and
a nonconductive layer covering at least a portion of at least one of the first or second electrically conductive pathways to resist current leakage between the pathways and thereby minimize electrolysis-induced corrosion.
7. The variable resistor card of claim 6 wherein the nonconductive layer is composed of a thick film insulating material.
8. The variable resistor card of claim 7 wherein the nonconductive layer is composed of a glass encapsulant.
9. The variable resistor card of claim 6 wherein at least a portion of the first electrically conductive pathway is within 2.0 mm of at least a portion of the second electrically conductive pathway.
10. The variable resistor card of claim 6 wherein at least a portion of at least one of the first or second electrically conductive pathways has a cross-sectional area of no greater than 0.5 mm 2 .
11. A fuel level sensor comprising:
a float arm mechanism including:
a base;
a float;
a float arm having a float end carrying the float and a base end pivotably carried by the base;
a variable resistor card carried by the base of the float arm mechanism and including:
a substrate at least partially composed of a ceramic material;
a resistive wiper contact area on the substrate;
a first electrically conductive pathway on the substrate and in electrical communication with the resistive wiper contact area;
a conductive wiper contact area on the substrate;
a second electrically conductive pathway on the substrate and in electrical communication with the conductive wiper contact area; and
a nonconductive layer covering at least a portion of one of the first or second electrically conductive pathways to resist current leakage between the pathways and thereby minimize electrolysis-induced corrosion.
12. The fuel level sensor of claim 11 wherein the nonconductive layer is composed of a thick film insulating material.
13. The fuel level sensor of claim 12 wherein the nonconductive layer is composed of a glass encapsulant.
14. The fuel level sensor of claim 11 wherein at least a portion of the first electrically conductive pathway is within 2.0 mm of at least a portion of the second electrically conductive pathway.
15. The fuel level sensor of claim 11 wherein at least a portion of at least one of the first or second electrically conductive pathways has a cross-sectional area of no greater than 0.5 mm 2 .