US 7,397,353 B2 · Wireless tire pressure and/or wheel speed sensing system for aircraft

Abstract

A wireless tire pressure sensing system for an aircraft comprises: dual resonant circuits mounted to a wheel of the aircraft, each resonant circuit comprising: a variable capacitance sensor and a wire loop of a predetermined inductance coupled thereto, one capacitance sensor for monitoring the pressure of a tire mounted to the wheel, and the other capacitance sensor operative as a reference to the one capacitance sensor; an interrogating circuit magnetically coupleable to the dual resonant circuits and operative to induce magnetically a variable frequency current in the dual resonant circuits, the one resonant circuit responding to the induced current with an E-field signal at a first resonant frequency commensurate with the capacitance of the one sensor, and the other resonant circuit responding to the induced current with an E-field signal at a second resonant frequency commensurate with the capacitance of the other sensor; a receiving circuit E-field coupleable to the dual resonant circuits and operative to receive the E-field signals at the first and second resonant frequencies and to generate first and second signals representative thereof, and a processing circuit coupled to the receiving circuit for processing the first and second signals to generate a compensated pressure reading of the tire. The pressure sensing system may be modified to provide and/or include wheel speed sensing.

Claims22

Dependent claims

A wireless tire pressure and wheel speed sensing system for an aircraft, said system comprising:

a resonant circuit mounted to a wheel of the aircraft for monitoring the pressure of a tire mounted to said wheel, said resonant circuit comprising a wire loop of a predetermined inductance;
an interrogating circuit magnetically coupleable to said resonant circuit and operative to induce magnetically a variable frequency current in the wire loop of said resonant circuit, said resonant circuit generating a corresponding variable frequency electric field in response to said induced current, said variable frequency electric field including a resonant frequency commensurate with the pressure of said tire;
a magnetic field altering apparatus for alternating the magnetic coupling between said wire loop and said interrogating circuit to cause a rate of amplitude modulations of said variable frequency electric field commensurate with said wheel speed;
a receiving circuit E-field coupleable to said resonant circuit and operative to receive said amplitude modulated variable frequency electric field of said resonant circuit and to generate a signal representative thereof;
a first processing circuit coupled to said receiving circuit for processing said signal to generate a pressure reading of said tire based on the resonant frequency thereof;
and
a second processing circuit coupled to said receiving circuit for processing said signal to generate a wheel speed reading based on the rate of amplitude modulations thereof.

4 more elements

Dependencies are inferred from the claim text.

Wireless tire pressure and/or wheel speed sensing system for aircraft

Life of this patent

Wireless tire pressure and/or wheel speed sensing system for aircraft

Life of this patent

Abstract

Claims22