×

Tire condition monitor

  • US 4,052,696 A
  • Filed: 03/01/1976
  • Issued: 10/04/1977
  • Est. Priority Date: 03/01/1976
  • Status: Expired due to Term
First Claim
Patent Images

1. A condition sensing circuit adapted for mounting on a vehicle wheel to monitor the condition of a tire and provide an indication of a change in condition through inductive coupling with signal monitoring and indicating apparatus mounted on the vehicle chassis, the sensor circuit comprising:

  • A. a toroidal ferrite element that switches from a ferromagnetic state to a nonferromagnetic state when the element temperature exceeds the Curie point established for the ferrite material;

    B. an inductive circuit for establishing a particular inductive coupling effect indicative of a normal tire condition when in proximate position to the signal monitoring apparatus; and

    C. means to couple the ferrite element into the inductive circuit comprising a pair of inductive coils wound on opposite halves of the toroid element and forming parallel branch circuits such that current flow in one of the branches is reversed when the element switches to a nonferromagnetic state due to a temperature above the Curie point, said current reversal effectively altering the particular inductive coupling effect for an abnormal tire condition indication.

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