US5648941A - Transducer backing material - Google Patents Connect public, paid and private patent data with Transducer backing material Info Publication number US5648941A Authority US Grant status Grant Patent type Prior art keywords fiber material preform acoustic backing Prior art date 1995-09-29 Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Expired - Fee Related Application number US08536763 Inventor Robert W. King Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.) Koninklijke Philips NV Original Assignee HP Inc Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.) 1995-09-29 Filing date 1995-09-29 Publication date 1997-07-15 Grant date 1997-07-15 Links • • • • • Images • • • • Classifications • • B— PERFORMING OPERATIONS; TRANSPORTING • B06— GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL • B06B— METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. An electroacoustic transducer having a base formed of a transducer backing material for use in supporting an array of active elements.

The backing material is formed as a composite of a preform, preferably selected according to a fiber architecture, and an acoustically-attenuating matrix. Preferred embodiments of the preform include linear, planar, and integrated fiber systems. A particularly preferred embodiment includes a macroporous mesh structure provided in the form of stacked sheets, or an integrated fiber system, having therein fibers arranged in spaced relationship. Download Whats App For Nokia 2690 there. The fibers define a plurality of openings which in turn provide voids that may be filled by the matrix via techniques such as vacuum-impregnation. FIELD OF THE INVENTION This invention relates to improvements in electroacoustic transducers, and in particular to backing materials for ultrasonic electroacoustic transducers. BACKGROUND OF THE INVENTION Electroacoustic transducers are generally comprised of an array of active elements in the form of piezoelectric crystals that are mounted in parallel, spaced relationship on the surface of a base of sound-absorbing material.

The base is typically constructed of a backing material that exhibits particular acoustical characteristics. For example, the backing material is typically formed by molding a composition of a material having a high acoustical impedance, such as tungsten powder, and an acoustically-absorbing binder so as to substantially eliminate spurious acoustic reflections. In constructing such a transducer, it is customary to adhere the back of a large crystal to the surface of the base and saw through it in parallel spaced planes so as to form the separate crystals of the array. Acoustic transducer arrays, and in particular ultrasonic transducer arrays, may be arranged in a number of configurations including linear, one-dimensional arrays, matrix two dimensional arrays, annular ring arrays, etc. Harmful coupling between the elements of the array by surface waves is substantially reduced by extending the cuts into the base. Antec Veris Fusion Black Manual.