Oil level/condition sensor

• US 6,799,458 B2
• Filed: 05/04/2001
• Issued: 10/05/2004
• Est. Priority Date: 05/04/2001
• Status: Expired due to Fees

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Thomson, Steven Douglas, Ismail, Keith N., Lecea, Oscar Alfonso
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): WILSON, KATINA M
• Application Number:
  US09/849,201
• Publication Number:
  US 20020162390A1
• Time in Patent Office: 1,250 Days
• Field of Search: 733/04.R, 732/90.R, 733/04.C, 338/38, 340/620, 361/284, 324/663, 324/671
• US Class Current: 73/304.00C
• CPC Class Codes: G01F 23/265 for discrete levels
• CPC Class Codes: G01F 23/268 mounting arrangements of probes
• CPC Class Codes: G01N 33/2888 Lubricating oil characteristics, e.g. deterioration lubricating properties G01N33/30

Abstract

An oil level/condition sensor includes a first level sensing tube, a common tube, and a second level sensing tube. The tubes are concentric to each other around a central axis. Moreover, the tubes are separated by plastic spacers which insulate the level sensing tubes from the common tube and maintain the concentricity of the tubes. Installed in the end of the first level sensing tube is a coupling/plug and disposed around the coupling/plug is a first condition sensing tube. The coupling/plug insulates the first level sensing tube from the first condition sensing tube and prevents fluid communication therebetween. A second condition sensing tube is attached to the second level sensing tube around the common tube and the first condition sensing tube. A ring-shaped insulator electrically isolates the second condition sensing tube from the second level sensing tube. The multiple tube configuration provides increased sensing surface area without increasing the length of the sensor or dramatically increasing the overall diameter of the sensor package. As such, the increased sensing surface area increases the signal strength and the accuracy of the sensor. Thus, the sensor is used in relatively shallow oil pans where the length of the sensor is constrained by the depth of the oil pan.

Claims

1. An oil sensor comprising:

at least a first level sensing tube;

at least a common tube surrounding the level sensing tube; and

at least a second level sensing tube surrounding the common tube, the second level sensing tube being electrically connected to the first level sensing tube, the common tube being separated from the first and second level sensing tubes.

2. The oil sensor of claim 1, further comprising:

a coupling/plug disposed in the end of the first level sensing tube; and

at least a first condition sensing tube disposed around the coupling/plug, the coupling/plug electrically insulating the first condition sensing tube from the first level sensing tube.

3. The oil sensor of claim 2, further comprising:

at least a second condition sensing tube attached to the second level sensing tube around the first condition sensing tube and the common tube, the second condition sensing tube being electrically insulated from the second level sensing tube and electrically connected to the first condition sensing tube.

4. The oil sensor of claim 1, wherein the tubes are concentric.

5. The oil sensor of claim 1, further comprising:

plural spacers disposed between the first level sensing tube and the common tube; and

plural spacers disposed between the common tube and the second level sensing tube.

6. The oil sensor of claim 1, wherein the sensor is disposed in a relatively shallow oil pan.

7. The oil sensor of claim 6, wherein the sensor is connected to a control module, the control module receiving a signal from the sensor representing a level of oil in the oil pan.

8. The oil sensor of claim 6, wherein the sensor is connected to a control module, the control module receiving a signal from the sensor representing a condition of oil in the oil pan.

9. The oil sensor of claim 7, wherein the control module is connected to a warning device, the warning device receiving a signal from the control module when the level of oil falls below a predetermined minimum.

10. The oil sensor of claim 8, wherein the control module is connected to a warning device, the warning device receiving a signal from the control module when the condition of the oil falls outside a predetermined operating range.