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:
Oct. 03, 1989
Filed:
Mar. 08, 1984
John P Kirby, Peabody, MA (US);
Richard Paglia, Carlisle, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
An ultrasonic transducer assembly capable of being operated in a corrosive and/or abrasive environment that might otherwise degrade transducer performance and/or damage transducer related components. The assembly includes an ultrasonic transducer of the type having a vibratile diaphragm supported at its periphery by a support housing and having the diaphragm center portion spaced a predetermined distance from a protective perforated cover. A channel is provided in the transducer between opposite sides of the vibratile diaphragm to avoid temperature induced pressure differentials between gases (air) present in the space immediately adjacent opposite diaphragm surfaces. A plastic film is adhesively attached to the outer surface of this diaphragm-protecting cover and the entire transducer is enclosed within an outer housing. A flexible seal engages the plastic film and an outer housing surface. With this arrangement the outer housing interior is divided into two isolated spacial volumes with one volume being in direct communication with the atmosphere and with the other volume (formed by the outer housing, plastic film and flexible seal) forming a chamber that completely isolates the entire ultrasonic transducer from its operating environment. A tube couples the interior of the transducer containing chamber to a corrosive gas and foreign particle free environment at a remote protected location for the purpose of neutralizing any performance-degrading and/or protective film distorting pressure differentials between the two spacial volumes while avoiding direct contact between the transducer and/or related components and environmental components in the atmosphere potentially harmful to transducer performance, during such pressure neutralization.