Fluid particle sensor apparatus and method for transmitting data to a remote receiver

• US 6,392,562 B1
• Filed: 12/28/1998
• Issued: 05/21/2002
• Est. Priority Date: 12/28/1998
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Unger, Bruce E., Scholl, Rolland D., Boston, Timothy A.
• Primary Examiner(s): EDWARDS JR, TIMOTHY
• Application Number:
  US09/221,400
• Time in Patent Office: 1,240 Days
• Field of Search: 340/870, 340/28, 340/631, 340/870.16, 324/204, 73/614.1, 73/614.2
• US Class Current: 340/870.28
• CPC Class Codes: G01N 15/0656 using electric, e.g. electrostatic methods or magnetic methods by investigating individual particles G01N15/1031, G01N15/12
• CPC Class Codes: G01N 33/2888 Lubricating oil characteristics, e.g. deterioration lubricating properties G01N33/30
• CPC Class Codes: G08C 17/02 using a radio link

Abstract

A sensor for detecting particles in a fluid including a housing having a cavity associated therewith, a magnet disposed adjacent the cavity to attract particles into the cavity, first and second coils wound around the outer surface of the cavity, the induction of the first coil being responsive to the particle accumulation within the cavity, the inductance of the second coil being responsive to the temperature of the fluid and being independent of the particle accumulation within the cavity, a first microprocessor coupled to the first and second coils for processing the signals received therefrom and for outputting signals indicative of the particle accumulation within the cavity, an rf transmitter for converting the signals received from the first microprocessor into rf signals, and an rf antenna for transmitting the processed signals to a remote location. The signals outputted from the first microprocessor are encoded with an identification code to identify and distinguish such signals. A second rf antenna and receiver are positioned at a remote location for receiving the transmitted rf signals. The receiver decodes and processes such transmitted rf signals back into an electrical signal indicative of the particle accumulation within the cavity and inputs such signal into a second microprocessor or electronic controller which stores and monitors such information for diagnostic, prognostic and trend analysis purposes.

Claims

1. A sensor system carried by a work machine for sensing particle accumulation within a fluid contained in a work machine component and transmitting a signal representative of such particle accumulation to a receiver carried by the work machine, said system comprising:

a sensor carried by a work machine positionable relative to a fluid and capable of generating an electrical signal responsive to the particle accumulation within the fluid;

a first microprocessor coupled to said sensor for receiving electrical signals therefrom and for outputting a signal indicative of the particle accumulation in the fluid;

a transmitter coupled to said first microprocessor for processing the signals received from said first microprocessor into rf signals and transmitting said rf signals;

a receiver carried by the work machine and positioned at a location remote from said transmitter for receiving the rf signals from said transmitter and processing said signals back into an electrical signal; and

a second microprocessor coupled to said receiver for receiving and storing the electrical signals from said receiver, said electrical signals being indicative of the particle accumulation within the fluid.

2. The sensor system as set forth in claim 1 wherein the sensor, first microprocessor and transmitter are powered by at least one battery carried by a portion of the sensor system.

3. The sensor system as set forth in claim 2 wherein the first microprocessor and transmitter operate alternately in a sleep mode and run mode.

4. The sensor system, as set forth in claim 1, wherein said second microprocessor produces a signal indicative of the particle accumulation in the fluid.

5. The sensor system, as set forth in claim 4, including a monitoring system adapted to receive signals from said second microprocessor and producing a warning signal in response thereto if said signal exceeds a predetermined value.

6. The sensor system, as set forth in claim 5, wherein said predetermined value is based upon a rate of increase of particle accumulation with the fluid.

7. The sensor system, as set forth in claim 5, wherein said sensor can be re-calibrated to change the predetermined value above which a warning signal will be produced by said monitoring system.

8. The sensor system, as set forth in claim 1, wherein said first microprocessor encodes the electrical signals received from said sensor with an identification code unique to said sensor.

9. The sensor system, as set forth in claim 8, wherein said receiver only processes those rf signals encoded with the identification code unique to said sensor.

10. The sensor system as set forth in claim 8 wherein there are a plurality of said sensors carried by the work machine each having a respective and first microprocessor and transmitter.

11. The sensor system as set forth in claim 10 wherein each sensor and respective microprocessor and transmitter are powered by a respective battery.

12. An apparatus carried by a work machine for detecting particles within a fluid contained in a work machine component, comprising:

a housing unit including a cavity, said housing unit carried by a work machine;

a first coil disposed adjacent said cavity to generate electrical signals responsive to the temperature of the fluid, said signal being independent of any particle accumulation within said cavity;

a second coil disposed adjacent said cavity to generate electrical signals responsive to the particle accumulation within said cavity, said electrical signals being representative of particle accumulation within said cavity in response to the change of the inductance of said second coil due to accumulation of particles within said cavity;

a first microprocessor coupled to said first and second coils for receiving electrical signals therefrom, said microprocessor encoding said electrical signals specific to said apparatus;

a transmitter coupled to said first microprocessor for transmitting said encoded signals to a remote location;

a receiver carried by said work machine and disposed at said remote location for discriminating among a plurality of signals in order to identify and decode signals specific to said apparatus; and

a second microprocessor coupled to said receiver for receiving signals from said receiver and producing a signal indicative of the particle accumulation within said cavity.

13. An apparatus, as set forth in claim 12, wherein the electrical signals representative of the identifying accumulation with said cavity are encoded with identifying information representative of said apparatus.

14. An apparatus carried by a work machine for detecting particles within a fluid contained in a work machine component comprising:

a housing adapted for at least partial placement in a fluid system and including a cavity, said housing being carried by a work machine;

a magnet disposed adjacent to said cavity and adapted to attract and contain particles within said cavity;

a first coil wound about the outer surface of said cavity, the inductance of said first coil being responsive to the particle accumulation within said cavity;

a second coil spaced from said first coil, the inductance of said second coil being responsive to the temperature of the fluid and being independent of any particle accumulation within said cavity;

a first microprocessor coupled to said first and second coils adapted to receive electrical signals therefrom, said first microprocessor determining the particle accumulation within said cavity and producing a detecting signal representative thereof;

an rf transmitter coupled to said first microprocessor for processing the detecting signal into an rf signal;

a first antenna coupled to said rf transmitter for transmitting the rf signal from said transmitter;

a second antenna carried by the work machine and positioned at the remote location from the first antenna for receiving the rf signal;

an rf receiver coupled to said second antenna for receiving and processing the rf signal into electrical signals, said electrical signals being representative of the particle accumulation within said cavity; and

a second microprocessor carried by the work machine and coupled to said rf receiver and adapted to receive electrical signals therefrom, said second microprocessor storing and monitoring the particle accumulation data represented by the signals received from said rf receiver.

15. The apparatus, as set forth in claim 14, wherein said housing includes first and second members, one of said members including said cavity and being engageable with said other member.

16. The apparatus, as set forth in claim 14, including a monitoring system adapted to receive a signal from said second microprocessor, said monitoring system producing a warning signal in response to the signal received from said second microprocessor if said signal exceeds a predetermined value.

17. The apparatus, as set forth in claim 14, wherein said first microprocessor and said rf transmitter are located within said housing.

18. The apparatus, as set forth in claim 14, wherein the signals representative of particle accumulation within said cavity are encoded with identifying information representative of said detecting apparatus.

19. The apparatus, as set forth in claim 18, wherein the electrical signal transmitted from said rf receiver to said second microprocessor includes the identifying information representative of said detecting apparatus.

20. The apparatus, as set forth in claim 17, including an oscillator selectively coupled to the first and second coils for producing an oscillating waveform, wherein the frequency of the oscillating waveform is a function of the induction of one of said first and second coils.

21. The apparatus, as set forth in claim 20, including a multiplexer adapted to select one coil to energize at a given time.

22. The apparatus, as set forth in claim 21, wherein the oscillator produces an oscillating waveform having a series of pulses the frequency of which is a function of the one energized coil inductance.

23. A method for detecting particles within a fluid contained within a work machine component comprising the following steps:

providing a sensor capable of detecting particle accumulation within a fluid in a work machine component and providing a signal indicative of said particle accumulation;

generating a signal indicative of the particle accumulation within the fluid;

encoding said signal with identifying information unique to said sensor;

converting said signal into an rf signal and transmitting said rf signal to a remote location on the work machine;

receiving said rf signal at said remote location;

decoding said rf signal based upon said identifying information unique to said sensor; and

reading and storing said decoded signal at said remote location wherein the particle accumulation within the fluid is monitored.

24. The method as set forth in claim 23 including providing at least one battery for powering the signal generation, the signal encoding and the rf signal transmitting steps.

25. The method as set forth in claim 23 wherein the signal generating, signal encoding and rf signal transmitting steps alternate between a run mode and a sleep mode.