Fluid-level sensor

Patent metadata

Field	Value
Publication number	US-11674840-B2
Application number	US-202117479689-A
Country	US
Kind code	B2
Filing date	Sep 20, 2021
Priority date	Sep 20, 2021
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

A fluid-level sensor includes a housing, a substrate supported by the housing and defining an arcuate slot completely though a thickness of the substrate, and electrically conductive traces disposed on a backside of the substrate. A wiper assembly is disposed adjacent to a front side of the substrate and includes an arm pivotal relative to the substrate and a wiper attached to the arm. The wiper has an elongate neck extending through the slot and a head attached to the neck and in contact with the traces to close an electric circuit, wherein the wiper is configured to move along the slot and slide across the traces responsive to pivoting of the arm to vary resistance of the electric circuit to output a fluid-level reading.

First claim

What is claimed is:

1. A fluid-level sensor comprising:
a housing;
a ceramic card supported by the housing and defining an arcuate slot completely through a thickness of the card, the card including a front side and a backside;
electrically conductive traces disposed on the backside of the card; and
a wiper assembly disposed adjacent to the front side of the card and including an arm pivotal relative to the card and a wiper attached to the arm, the wiper including an elongate neck extending from the front side, completely through the slot, and to the backside, the wiper further including a head attached to the neck and in contact with the traces to close an electric circuit, wherein the wiper is configured to move along the slot on the backside of the card and slide across the traces responsive to pivoting of the arm to vary resistance of the electric circuit to output a fluid-level reading, wherein the arm is located on the front side of the card and the head is located on the backside of the card.

2. The fluid-level sensor of claim 1 further comprising a float attached to the arm and configured to rise and fall with fluid level to pivot the arm.

3. The fluid-level sensor of claim 1 wherein the traces extend along at least a portion of a periphery of the slot.

4. The fluid-level sensor of claim 1 , wherein the slot has an enlarged opening at one end configured to receive the wiper therethrough and a main portion that is narrower than the opening.

5. The fluid-level sensor of claim 4 , wherein the head has a width that is wider than the main portion to inhibit removal of the wiper from the slot and is narrower than the opening such that the head is capable of insertion and removal only at the opening.

6. The fluid-level sensor of claim 1 , wherein the wiper is tee-shaped.

7. The fluid-level sensor of claim 6 , wherein the head is wider than the slot and the neck is narrower than the slot.

8. The fluid-level sensor of claim 1 , wherein the wiper is pre-tensioned away from the arm such that the head is urged into contact with the traces.

9. The fluid-level sensor of claim 8 , where the neck incudes a first side facing the arm and a second side facing the substrate, wherein the pre-tension puts the first side in tension and the second side in compression.

10. The fluid-level sensor of claim 1 , wherein the neck extends away from the arm at an oblique angle.

11. A fluid-level sensor comprising:
a housing;
a substrate supported by the housing and defining an arcuate slot completely though a thickness of the substrate;
electrically conductive traces disposed on a backside of the substrate, wherein the traces include a first trace extending along one side of the slot and a second trace extending along another side of the slot; and
a wiper assembly disposed adjacent to a front side of the substrate and including an arm pivotal relative to the substrate and a wiper attached to the arm, the wiper including an elongate neck extending through the slot and a head attached to the neck and in contact with the traces to close an electric circuit, wherein the wiper is configured to move along the slot and slide across the traces responsive to pivoting of the arm to vary resistance of the electric circuit to output a fluid-level reading.

12. The fluid-level sensor of claim 11 further comprising a float attached to the arm and configured to rise and fall with fluid level to pivot the arm.

13. The fluid-level sensor of claim 11 , wherein the wiper is pre-tensioned away from the arm such that the head is urged into contact with the traces.

14. A fluid-level sensor comprising:
a substrate defining an arcuate slot and having electrically conductive traces disposed on a backside of the substrate, wherein the traces include a first trace extending along one side of the slot and a second trace extending along another side of the slot; and
a wiper assembly including an arm pivotal relative to the substrate and located on a front side of the substrate, and the wiper assembly further including an electrical contact attached to the arm, the contact extending completely through the slot and disposed against the traces to form an electric circuit having resistance dependent upon a circumferential position of the contact within the slot to output a fluid-level reading.

15. The fluid-level sensor of claim 14 , wherein the slot extends through a thickness of the substrate.

16. The fluid-level sensor of claim 15 , wherein the contact includes a neck disposed in the slot with a first portion on the front side and a second portion on the backside and a head connected to the second portion and in contact with the traces.

17. The fluid-level sensor of claim 14 , wherein the slot has an enlarged opening at one end configured to receive the contact therethrough and a main portion that is narrower than the opening.

18. The fluid-level sensor of claim 17 , wherein the contact is tee-shaped with a head being wider than the main portion and narrower than the enlarged opening.

19. The fluid-level sensor of claim 14 , wherein the contact is elastically deformed such that the contact is urged against the traces.

Assignees

• Ford Global Tech Llc

Inventors

• Mondragón Avelar José David
• Rosas Contreras Sebastian
• Soriano Canchola Tanya Stephany
• Benítez Torreblanca Miguel Ángel
• Sharp Sheven

Classifications

• G01F23/363 Primary

  using electromechanically actuated indicating means · CPC title

• G01F23/24

  by measuring variations of resistance of resistors due to contact with conductor fluid · CPC title