×

Self-calibrated subcarrier telemetry system

  • US 4,225,851 A
  • Filed: 03/22/1979
  • Issued: 09/30/1980
  • Est. Priority Date: 03/22/1979
  • Status: Expired due to Term
First Claim
Patent Images

1. In combination with apparatus having a stationary member, and a heavy rotational member or rotor adapted to rotate at high speed within said stationary member, a telemetry system for detecting strain on a part of said rotational member comprising:

  • (a) a transducer-data transmission portion mounted on and rotatable with said rotational member;

    (b) a stationary data reception-readout portion having means for generating a radio frequency (RF) signal, said RF signal being supplied to said transducer-data transmission portion and to said data reception-readout portion;

    (c) means for inductively coupling signals between said transducer-data transmission portion and said data reception-readout portion;

    (d) said transducer-data transmission portion including(d1) a first means for frequency division of said RF signal to provide a lower frequency subcarrier signal;

    (d2) a strain gage transducer adapted for excitation by said subcarrier signal and responsive to strain on said rotational member by producing a corresponding amplitude modulated signal at the subcarrier frequency;

    (d3) an FM transmitter for receiving said amplitude modulated signal and generating a carrier signal for transmission through said inductive coupling means to said stationary data reception-readout portion, said carrier signal being frequency modulated by said amplitude modulated signal; and

    (e) said data reception-readout portion including(e1) a second means for frequency division of said RF signal to provide a reference signal equal in frequency to said subcarrier signal;

    (e2) an FM receiver for receiving and demodulating said carrier signal to yield said amplitude modulated signal; and

    ,(e3) a synchronous detector having a first input for receiving said reference signal and a second input for receiving said amplitude modulated signal from said FM receiver, said synchronous detector producing a demodulated signal representative of strain on said rotational member.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×