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:
May. 04, 1999
Filed:
Mar. 28, 1997
Ching Chu, Madison, WI (US);
Neil D Roiland, Deerfield, WI (US);
Ohmeda Inc., Liberty Corner, NJ (US);
Abstract
An ultrasonic transducer is disclosed for emitting an ultrasonic wave radially inward. The transducer is constructed with a strip of piezoelectric material laminated with a pair of electrically conductive metal layers that are conductively isolated from one another. In a preferred embodiment, the strip of piezoelectric material is formed in a cylindrical shape and with continuous sinusoidal ripples along the circumference. The sinusoidal ripples are designed to emit a specific wave length of a desired frequency. The radius of the sinusoidal wave is based on material characteristics and the desired resonance frequency. The invention discloses various methods and apparatus for constructing and maintaining the transducer sinusoidal shape. One method includes attachment of a pair of rigid end caps on the laminated piezoelectric material, and another discloses weaving the laminated piezoelectric material through a nonconductive mesh cage, and yet another includes adhesively attaching the transducer to a housing. The invention also includes an application of the above described transducers in a gas analyzer having an internal chamber in which the transducer is arranged. The method of analyzing gas includes passing the gas through the internal chamber and across the surface of the transducer, energizing the transducer to emit an ultrasonic wave into the passing gas toward the center of the transducer. The ultrasonic wave is reflected from a pressure center and sensed by the same transducer that emitted the wave. The invention also includes a method of manufacturing the transducer with sinusoidal ripples to accomplish an emission of desired frequency.