The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 18, 2003
Filed:
Mar. 29, 1999
Ryszard Marian Lec, Philadelphia, PA (US);
Other;
Abstract
A method and apparatus are described for noncontact measurement of torque applied to a torque-bearing member such as a shaft. The method involves the use of a piezoelectric transducer mechanically coupled to the shaft for rotation therewith, and having electrical characteristics responsive to applied torque. Electrical signal characteristics are changed by the torque-dependent transducer characteristics. The electrical signals are coupled to the outside (non-rotating) world by at least one capacitive coupler. In one embodiment, an fixed-frequency oscillator produces signal, and the transmission of the signal is affected by the torque-dependent resonant frequency of the transducer. In another embodiment, the transducer is coupled in the feedback loop of a circuit to form an oscillator, in which the frequency is responsive to the torque. A transducer may be placed and distributed in a protective holder. The holder may be pierced in particular locations in order to increase or decrease its sensitivity. One transducer is in the form of a monolithic mounting/transducer.