A transducer having an energy conversion medium for converting changes in applied mechanical energy into corresponding changes in thermal energy and a pyroelectric material in thermal energy transfer relationship with the energy conversion medium for producing an electrical output substantially in response to the converted thermal energy. Such transducer is particularly useful as a hydrophone in detecting low frequency sound waves emitted by, or reflected from, underwater objects.
Combinations of oppositely poled piezoelectric shapes which, when electrically stimulated, effect increased linear or rotational displacement. In a typical arrangement a length of PVDF piezoelectric material poled in one direction is spatially separated from a second similarly shaped length of PVDF piezoelectric material poled in the opposite direction by an electrically inert substance. When stimulated by an appropriate voltage, one length contracts while the other length expands producing an increased deflection in the combination.
The present invention relates to compact solid state silicon-based condenser microphone systems suitable for batch production. The combination of the different elements forming the microphone system is easier and more economical to manufacture compared to any other system disclosed in prior art. In addition the invention is compatible with electronic equipment manufacturing processes, such as SMD pick and place techniques. The invention uses a transducer chip comprising a chamber, a diaphragm that is positioned at the first lower surface and covering the second opening of the transducer chip. The transducer chip is flip-chip mounted onto a post-processed chip also comprising a chamber. The microphone system can be electrically connected to an external substrate by conventional techniques such as wire bonding.
A composite piezoelectric transducer, whose piezoeletric element is a "ribbon wound" film of piezolectric material. As the film is excited, it expands and contracts, which results in expansion and contraction of the diameter of the entire ribbon winding. This is accompanied by expansion and contraction of the thickness of the ribbon winding, such that the sound radiating plate may be placed on the side of the winding.
A power transfer system for converting recurring wave movement within the ocean to electrical energy. The system comprises pressure sensing structure such as a pressure transducer 10 or combination movable magnet and coil 50, positioned below water level and at a location 20 of wave movement for (i) registering changes in height of water 18 and 19 above the pressure sensing structure 10, 50 and (ii) providing electrical power output at the ocean floor corresponding to changes in gravity force associated with the changes in the height of water. A transfer medium 12 is coupled at one end to the pressure sensing structure and extends at a second end to a shore location. A power receiving device such as a bank of storage batteries 14 or electrical load is coupled to the transfer medium at the shore location for receiving the power output from the transfer medium and for processing the power for use.
A roof system for a building is adapted to harness pyroelectric and piezoelectric effects to generate electric power. A roof system is provided wherein roof tiles, or other covering structure, are adapted with piezoelectric materials capable of converting mechanical energy from falling rain into electric energy by compression or deformation of the piezoelectric material, and further adapted with a pyroelectric system that generates electric power from temperature changes. The use of polyvinylidene fluoride, a material having both piezoelectric and pyroelectric characteristics, is discloses as a preferred material for accomplishing the goals of the present invention. The power generated supplies thermoelectric cooling systems that provide temperature conditioning of the building's interior space.
