Oil quality sensor system, method and apparatus

• US 6,718,819 B2
• Filed: 09/10/2001
• Issued: 04/13/2004
• Est. Priority Date: 09/10/2001
• Status: Expired due to Fees

• Current Assignee: FRAM Group IP, LLC
• Original Assignee: Honeywell International Inc.
• Inventors: Schoess, Jeffrey N.
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): JACKSON, ANDRE K
• Application Number:
  US09/950,196
• Publication Number:
  US 20030046985A1
• Time in Patent Office: 946 Days
• Field of Search: 73/530.5, 73/614.1, 73/616.1, 324/448, 210/85, 210/86, 210/799, 210/416.5, 210/168, 210/167
• US Class Current: 73/53.05
• CPC Class Codes: B01D 27/08 Construction of the casing
• CPC Class Codes: B01D 29/60 integrally combined with devices for controlling the filtration
• CPC Class Codes: G01N 33/2888 Lubricating oil characteristics, e.g. deterioration lubricating properties G01N33/30

Abstract

An apparatus for determining the condition of engine lubricating oil includes a sensor having a plurality of spaced apart electrode pairs on a nonconductive polymer film. The sensor is operatively associated with an oil filter, which provides retro-fit capability and easy access for servicing and replacement. The multi-electrode pair design averages signal output to reduce operational electromagnetic interference noise. A forcing-function waveform reactive circuit is applied to the sensor input electrode as a common voltage potential. The output current from the sensor electrodes is then relayed to a current follower amplifier, which converts the output current into an equivalent voltage for comparison with predetermined values. Based on the voltage values, the on-board sensing system will determine the oil'"'"'s condition, and will trigger a trouble code if the equivalent voltage falls within a predetermined range.

Claims

1. An oil quality sensing system, comprising:

an oil filter;

a conductivity sensor attached to the oil filter, said conductivity sensor comprising a plurality of spaced apart electrode pairs mounted on a nonconductive film substrate, configured as a linear array or said electrode pairs extending in a band around an inner wall of the oil filter;

a waveform generator;

a measuring device for measuring a signal reflected by the sensor,

a comparing device, and

a signal generator.

2. An oil quality sensing system, comprising:

an oil filter;

a conductivity sensor attached to the oil filter, said conductivity sensor comprising a plurality of spaced apart electrode pairs mounted on a nonconductive film substrate, configured as a substantially circular array of said electrode pairs extending in an annular band around the underside of a tapping plate of said oil filter;

a waveform generator;

a measuring device for measuring a signal reflected by the sensor,

a comparing device, and

a signal generator.

3. An oil quality sensing system, comprising:

an oil filter;

a conductivity sensor attached to the oil filter, said conductivity sensor comprising a plurality of spaced apart electrode pairs mounted on a nonconductive film substrate;

a waveform generator;

a measuring device for measuring a signal reflected by the sensor,

a comparing device,

a signal generator; and

a flexible electrical cable, electrically connected to said sensor and extending away from the oil filter, and a disconnectable plug attached to the cable.

4. A sensor for immersing placement in oil to monitor the condition thereof, said sensor comprising:

a nonconductive film of a polymeric substrate; and

plurality of spaced apart electrode pairs applied to a first surface of the substrate; and

a pressure-sensitive adhesive applied to a second surface of the substrate opposite the first surface.

5. A sensor for immersing placement in oil to monitor the condition thereof, said sensor comprising:

a nonconductive film of a polymeric substrate;

a plurality of spaced apart electrode pairs applied to a first surface of the substrate;

a first electrode connector strip extending laterally on the substrate;

a plurality of spaced apart electrodes extending from said first connector strip and in electrical communication therewith;

a second electrode connector strip extends laterally on the substrate, spaced from the second connector strip; and

a plurality of spaced apart electrodes extending from said second connector strip and in electrical communication therewith.

6. The sensor of claim 5, wherein the electrodes of the first and second connector strips are interdigitated.