Pennwalt Corporation

Other

The Whitaker Corporation

Peter F Radice

Kyung T Park

James P King

Mitchell L Thompson

Joseph Simkin

Joseph V Chatigny

Richard A Ferren

Donald L Halvorsen

A traffic sensor including piezoelectric sensors having different polarities in different lanes of the roadway so that traffic data for different lanes of a roadway may be discriminated from the polarity of the received signal(s). Preferably, the piezoelectric sensors are formed by splicing oppositely polarized piezoelectric cables or films, by changing the applied electric field during manufacture so that adjacent portions of a piezoelectric cable or film have different polarities, or by applying an electric field of a reversed polarity to respective longitudinal sections of a piezoelectric film. Traffic data from up to 8 different lanes of traffic may be discriminated using only two piezoelectric sensors in accordance with the invention by providing unique combinations of output polarities for deflections of the piezoelectric sensors in the different lanes. In order to simplify installation, such piezoelectric sensors may be disposed in parallel within the same housing or concentrically within the same cable.

Traffic sensor having piezoelectric sensors which distinguish lanes

An electroacoustic novelty, particularly to the brim on an article of headware, or to a flag, containing a piezoelectric polymer film, where means are electrically coupled with electrodes on the film for applying an audio-frequency signal voltage across the film to cause the film to vibrate and emit sound waves.

Electroacoustic novelties

Electroacoustic novelties are disclosed having a piezoelectric polymer film which functions as a speaker or microphone. The novelties include flags, banners, posters or articles of headwear. The piezoelectric polymer film may be attached to a portion of the flexible substrate forming the novelty, or it may be used as an integral part of the novelty structure. An audio output or recording device is electrically coupled to the piezoelectric polymer film. Both the piezoelectric polymer film and the electrodes may be transparent so that the adjoining portion of the novelty is visible.

Piezoelectric polymer film, when conformably adhered to inner or outer surfaces of an inflated balloon, functions as a microphone when the pressure of sound waves causes the film to vibrate and generate an electrical signal. The film may be in the form of an helical strip, individual strips electrically serially connected, or may itself form the inflatable material. A receiving device is electrically coupled with the electrodes formed on the piezoelectric film for processing the electrical signals generated by the vibrating piezoelectric polymer film.

Air buoyant piezoelectric polymeric film microphone

Piezoelectric polymer film transducers include a metallized film electrode deposited on each of the two surfaces of the film. The electrodes are provided with leads extending therefrom in staggered parallel relationship. Each lead of the improved connector is associated with a reinforced assembly comprising plastic strips, a terminal connector, optional spacer washers, and a metal rivet penetrating the assembly such that electrical contact is effected between the lead and terminal connector. To insure positive electrical contact, a conductive ink may be deposited on one of the plastic strips through which an orifice is provided. The orifice communicates with a selected lead. The ink coats walls of the orifice to insure electrical continuity between the lead and terminal connector. A modified connector assembly disposes the reinforced connectors beyond the edges of a substrate which carries or supports the piezoelectric polymer film transducers.

Connectors for use with piezoelectric polymeric film transducers

Piezoelectric polymer film, when conformably adhered to inner or outer curved surfaces of an inflated balloon, for example, acts as a speaker when the metallized coatings of the film are suitably connected to the output of an audio device. The film may be in the form of an helical strip, or individual strips elastically serially connected, or may itself form the inflatable material. Amplifying and impedance matching means may be interposed between the audio output and film coatings.

Piezoelectric polymeric film balloon speaker

Electrodes with leads deposited on different surfaces of a piezoelectric polymeric film or films are easily and quickly electrically connected by forming a continuous channel through the film and lead to form a pierced lead, and then applying an electrically conductive material, by any one of several known processes, onto the film over the channel to thereby form a connecting lead, the conductive material being permitted to penetrate the channel to effect a continuity of conductive material between the pierced lead and connecting lead.

Means for electrically connecting electrodes on different surfaces of

An embodiment of a non-contact electrical keyboard switch which completely resists EMI and eliminates cross-talk comprises a pair of electrically insulating substrates having rows and columns of openings therethrough. A poled piezoelectric PVDF film is adhered to each substrate over the openings. The films have silk-screened ground electrodes deposited on one surface and signal generating key electrodes deposited on the other surface in registration with the openings. Leads connecting individual rows of key electrodes on one film and individual columns of key electrodes on other film are disposed orthogonally. An insulating sheet separates the films which have their key electrode surfaces facing each other. Leads are connected to ground and/or suitable electrical connectors to provide the keyboard switch. Processes are disclosed for fabricating embodiments of the keyboard switch.

Piezoelectric polymer keyboard apparatus

Methods are disclosed for stabilizing poled piezoelectric and pyroelectric polymer films by exposing the poled film to a glow discharge at a reduced pressure for a sufficient period to thereby remove unwanted and unstable homo- and hetero-charges from the poled film.

Glow discharge stabilization of piezoelectric polymer film

Polymeric films exhibiting piezoelectric properties have such properties enhanced by being subjected to improved poling apparatus of the present invention comprising a textured corona discharge electrode roller oscillating over the polymeric film, preferably polyvinylidene fluoride, while the film is simultaneously slowly transported on a rotating drum. The electrode continuously discharges corona through the film while sweeping back and forth thereover. Comparatively low voltages are employed and dielectric breakdown of the film is substantially non-existent. A protective reuseable co-film is preferably interposed between the oscillating electrode and film to be poled.

Apparatus for the rapid continuous corona poling of polymeric films

The present invention provides a process for preparing piezoelectric film using a corona discharge device wherein a multi-layer of pellicles, of which at least one or more is a piezoelectric sensitive film and at least one other of the multi-layer is a companion pellicle (i.e. a pellicle with a conductance no less than that of the piezoelectric sensitive pellicle when the conductance is measured under the poling conditions of the corona discharge and in the direction of the discharge field), is subjected to a corona discharge between a pair of electrodes of which at least one such electrode has a textured surface.

Corona discharge poling process

A device for verifying personal hand markings, e.g., signatures, and optionally, voice-produced sound, by comparison of electronically produced representations thereof with similar stored information wherein such representations are produced by variations of electrical energy caused by hand markings on a surface adapted to receive said markings and comprising a poled sheet of a piezoelectric-forming resin.

Personal verification device

A polarized pellicular resin article is prepared by bringing one surface of a pellicle of a polarizable, dielectric resin into intimate contact with a single electroconductive surface and charging said electroconductive surface with an electric potential at least sufficient to polarize said pellicular resin article.

Single electrode poling of dielectric films

A stabilized piezoelectric resin element is produced by applying high pressure to a poled piezoelectric resin element for a given time and short circuiting the surface of said element under pressure.

Stabilization of piezoelectric resin elements

Improved coatings having resistance to high temperature degradation are obtained by modifying a zirconium phosphinate polymer with phosphinic acid and a pigment. Acrylate or alkyd resins may also be included in the formulation.

Growing community of inventors

King of Prussia, PA, United States of America

Peter F Radice