摘要:
The invention relates to an electro-acoustic transducer using a self-supporting active radiating membrane made from a polymer material. The invention provides a transducer in which a resilient shape restoring member fixed to the case capped by the radiating membrane takes on the shape of the concave parts of the membrane, so as to oppose the definitive staving-in of the membrane by an accidental thrust force acting on the dome shaped protuberance on its outer face and restore the member to its initial shape when the force is removed.
摘要:
The invention relates to the manufacture of electromechanical transducers with at least one element made from a polymer material shaped and polarized so as to obtain an active self-supporting structure having a nondevelopable surface and to a manufacturing process which consists in shaping a structure already coated with metalizations, so that the electric polarizing field may be applied to the structure during shaping and until return thereof to ambient temperature.
摘要:
The invention relates to the production of blocks of macromolecular material displaying piezoelectric and pyroelectric properties and provides a production process consisting in drawing a thin strip of a film of macromolecular material from a feed reel, electrically polarizing the said film and coating it with adhesive by means of a solution based on a polymeric binder before the forming on a mandrel of a roll of which the turns form, after drying, a monolithic structure which may be split into blocks.The invention finds particular use in the production of electromechanical transducers for applications connected with electroacoustics and underwater acoustics.
摘要:
In a method of fabrication of piezoelectric polymer transducers by forging, a preform is subjected to flattening by compression in order to produce a radial orientation of the molecular chains constituting the polymer with respect to the center of pressure.
摘要:
A composite co-laminated piezoelectric transducer with at least one layer of polymeric substance capable of acquiring piezoelectric properties when co-laminated in the presence of an electrical field, the layer being adjacent to a conductive material acting as an electrode. According to the invention the conductive material is a polymeric substance.
摘要:
The invention relates to piezoelectric or pyroelectric polymer materials. It provides a process for manufacturing these materials comprising pressing polymer pellets while heating, dipping the obtained sheets in water, stretching the sheets, electrically polarizing the sheets by applying between the two faces of the sheets an electric orientation field, irradiating the sheets to obtain crosslinking and reheating the sheets.
摘要:
The invention relates to piezoelectric polymer films.The invention relates to a production process consisting of stretching a polymer material blank by rolling under an electrical field between two oppositely rotating rollers.The invention is more particularly applicable to the production of electromechanical transducers, whose active elements are constituted by piezoelectric polymer films provided with electrodes.
摘要:
A thermal detector with a monolithic structure comprises a layer of material sensitive to infrared radiation and an insulating layer constituted by a thermostable polymer that can be deposited as a thin layer and has a microporous structure. This insulating layer enables the thermal decoupling of the sensitive layer from the substrate comprising reading circuits with which the detector is provided. The performance characteristics of currently used monolithic infrared detectors can thus be substantially improved through the notable reduction of the thermal losses in the sensitive layer. This is achieved through the greatly reduced thermal conductivity of the layer of dielectric polymer. Application to infrared imaging devices.
摘要:
A thermal detector with a monolithic structure comprises a layer of material sensitive to infrared radiation and an insulating layer constituted by a thermostable polymer that can be deposited as a thin layer and has a microporous structure. This insulating layer enables the thermal decoupling of the sensitive layer from the substrate comprising reading circuits with which the detector is provided. The performance characteristics of currently used monolithic infrared detectors can thus be substantially improved through the notable reduction of the thermal losses in the sensitive layer. This is achieved through the greatly reduced thermal conductivity of the layer of dielectric polymer. Application to infrared imaging devices.
摘要:
An electronic card having an electronic control circuit, an elector-optical element configured as a normal operation indicator, and a power supply source. Electrical tracks connect the electronic control circuit with the electro-optical element and the power supply source, and affixing elements attach the electronic card to a substantially planer surface. The electrical tracks having embrittlement grooves which destroy the connections made by the electrical tracks upon removal of the electronic card from the substantially planer surface to which the electronic card is attached. The electronic card is suited for applications in the identification and automatic detection of objects and in particular, stolen vehicles.