Telemetric measuring device with high power generation

• US 5,151,695 A
• Filed: 10/02/1990
• Issued: 09/29/1992
• Est. Priority Date: 10/02/1990
• Status: Expired due to Fees

• Current Assignee: Southwest Research Institute
• Original Assignee: Southwest Research Institute
• Inventors: Davis, James K., Burrahm, Robert W., Perry, William D., De Los Santos, Armando, Rollwitz, William L.
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): Krakovsky, Michael
• Application Number:
  US07/591,952
• Time in Patent Office: 728 Days
• Field of Search: 340/870.33, 340/870.3, 340/870.13, 340/870.16, 340/870.26, 340/870.17, 324/207.15, 324/174, 331/65, 331/66, 331/60, 322/3, 310/15, 307/116, 307/125, 361/143
• US Class Current: 340/870.33
• CPC Class Codes: G08C 17/02 using a radio link
• CPC Class Codes: G08C 19/06 using variable inductance
• CPC Class Codes: H02K 35/06 with moving flux distributors, and both coil systems and magnets stationary

Abstract

A telemetric measuring device for measuring physical conditions of machinery having a periodically moving part. The device generates its own power with power generator that uses the periodic motion of the machinery to move a reciprocator slug inside a coil, and thereby opening and closing a magnetic circuit and generating a continuous alternating current. This current powers a transmitter that receives output from a multi-channel switch for a number of sensors. The transmitter delivers a radio frequency signal, whose frequency is a function of the condition being measured.

Claims

1. A power generator for a telemetric measuring device for measuring physical conditions of machinery having a moving part, comprising:

a magnet for energizing a magnetic circuit, said magnet being fixed with respect to said moving part;

a coil for providing induced electrical current, said coil being fixed with respect to said moving part; and

a reciprocator slug, made from a magnetically conductive material, placed inside said coil and moveable with respect to said magnet and said coil, such that said slug is free to move in response to inertial forces provided by said moving part, thereby opening and closing said magnetic circuit and inducing an electrical current in said coil.

2. The power generator of claim 1, and further providing a means for offsetting the magnetic force on said slug.

3. The power generator of claim 1, wherein said means for offsetting the magnetic force comprises a spring attached to said moving part.

4. The power generator of claim 1, wherein said slug has an enlarged cap portion outside said coil.

5. The power generator of claim 1, wherein said power generator generates continuous power while said moving part is in motion.

6. The power generator of claim 1, wherein said power generator generates a positive signal and a negative signal of different magnitudes.

15. The power generator of claim 4, wherein said cap portion is separated from said magnetic circuit by an air gap, which is opened and closed so as to cause said slug to make or break contact with said magnetic circuit as said slug moves.

16. The power generator of claim 4, wherein slug is stopped at one end by an end plate and said cap portion is at the impact end of said slug.

7. A telemetric measuring device for measuring physical conditions of machinery having a periodically moving part, comprised of:

a power generator having a coil, a magnet, and a reciprocator slug, wherein said magnet and said coil are fixed with respect to said machinery and said reciprocator slug is made from a magnetically conductive material and is moveable inside said coil such that it may move inertially in response to the motion of said moving part, wherein said reciprocator slug opens and closes a magnetic circuit formed at least in part by said magnet and said reciprocator slug as it moves;

a rectifying circuit connected to said coil for rectifying the signal generated by said power generator;

a transmitter, powered by said power generator and connected to said rectifier, for transmitting electrical signals; and

at least one sensor for acquiring data representing a physical condition of said machinery.

8. The power generator of claim 7, and further providing a means for offsetting the magnetic force on said slug.

9. The measuring device of claim 7, wherein said transmitter is a blocking oscillator circuit and said sensor is a component of said oscillator circuit.

10. The measuring device of claim 7, and further comprising a multi-channel switch powered by said power generator for acquiring data from multiple sensors and for delivering a selected channel of said data to said transmitter.

17. The power generator of claim 7, wherein said slug has an enlarged cap portion extending outside said coil, and wherein said cap portion is separated from said magnetic circuit by an air gap, which is opened and closed so as to cause said slug to make or break contact with said magnetic circuit as said slug moves.

18. The power generator of claim 17, wherein slug is stopped at one end by an end plate and said cap portion is at the impact end of said slug.

19. The measuring device of claim 7, and further comprising a plurality of said sensors and wherein said power generator generates an asymmetrical positive and negative voltage output, and further comprising a multiplexer for selecting among said sensors wherein said multiplexer is powered by said asymmetrical voltage output.

11. A telemetric measuring system for measuring physical conditions of machinery having a moving part, comprised of:

a measuring device having a magnetic power generator having a coil, a magnet, and a reciprocator slug, wherein said magnet and said coil are fixed with respect to said machinery and said reciprocator slug is moveable inside said coil such that it moves in response to the motion of said moving part, wherein said reciprocator slug is made from a magnetically conductive material and opens and closes a magnetic circuit formed at least in part by said magnet and said reciprocator slug as it moves;

a rectifying circuit connected to said coil for recitfying the signal generated by said power generator;

a transmitter connected to said rectifier for transmitting electrical signals;

a multi-channel switch for acquiring data from multiple sensors and for delivering a selected channel of said data to said transmitter; and

a sensing unit having a number of sensors, each for acquiring data representing a physical condition of said machinery;

an antenna for receiving said transmitted signals at a remote location;

a receiver for detecting a frequency of said signal; and

a converter for converting said frequency to data representing a measured value.

20. The power generator of claim 11, wherein said slug has an enlarged cap portion extending outside said coil, and wherein said cap portion is separated from said magnetic circuit by an air gap, which is opened and closed so as to cause said slug to make or break contact with said magnetic circuit as said slug moves.

12. A method of measuring physical conditions associated with machinery having a moving part, comprising the steps of:

attaching a magnet and a coil to a moving part of machinery;

placing a reciprocating slug made from a magnetically conductive material inside said coil;

generating power for a transmitter, using said slug to open and close a magnetic circuit, which is formed at least in part by said magnet and said slug, in response to motion of said moving part, while said coil and said magnet remain stationary;

acquiring data from a first sensor of said measuring device;

converting said data to a radio frequency signal; and

transmitting said radio frequency signal to a receiver via an antenna, using power generated by said power generating step.

13. The method of claim 12, and further comprising the step of switching to a second sensor and repeating said converting and transmitting steps, using power generated by said power generating step.

14. The method of claim 12, and further comprising the step of offsetting the magnetic force on said slug to reduce to inertial force required to move said slug.

21. The method of claim 13, wherein said generating step produces an asymmetrical voltage output and wherein said switching step uses said asymmetrical output to bias switching transistors.