Piezoelectric snap action switch

A non-contact piezoelectric switch comprising:

• a first snap action plate with a curved surface;
• a second snap action plate with a curved surface;
• a piezoelectric polymer film having respective surfaces disposed between said curved surfaces of said first and second snap action plates, whereby upon depression of at least one of said snap action plates said piezoelectric polymer film is extended or contracted along the surface thereof so as to conduct an electrical signal between said first and second snap action plates;
• and
• a chamber having a fluid normally pressurized to a predetermined level, said first and second snap action plates being disposed across an opening in said chamber so as to be depressed by a change in a pressure differential between the inside and outside of said chamber, whereby conduction of said electrical signal indicates the presence of said change in said pressure differential.

A non-contact piezoelectric switch comprising:

• first and second conductors;
• a first snap action plate with an upwardly convex surface electrically connected to said first conductor;
• a second snap action plate with an upwardly convex surface electrically connected to said second conductor;
• a piezoelectric polymer film having respective surfaces disposed between said upwardly convex surfaces of said first and second snap action plates;
• first and second electrodes disposed on said respective surfaces of said piezoelectric polymer film;
• and
• a third conductor intermediate of said first and second conductors, whereby upon depression of at least one of said snap action plates said first, second and third conductors are brought into electrical contact with each other and said piezoelectric polymer film is extended or contracted along the surface thereof so as to conduct an electrical signal between said first and second conductors via said first and second electrodes.

A non-contact piezoelectric switch comprising:

• first and second conductors;
• a first snap action plate with an upwardly convex surface electrically connected to said first conductor;
• a second snap action plate with an upwardly convex surface electrically connected to said second conductor;
• a piezoelectric polymer film having respective surfaces disposed between said upwardly convex surfaces of said first and second snap action plates;
• first and second electrodes disposed on said respective surfaces of said piezoelectric polymer film, whereby upon depression of at least one of said snap action plates said piezoelectric polymer film is extended or contracted along the surface thereof so as to conduct an electrical signal between said first and second conductors via said first and second electrodes;
• and
• a chamber having a fluid normally pressurized to a predetermined level, said first and second snap action plates being disposed across an opening in said chamber so as to be depressed by a change in a pressure differential between the inside and outside of said chamber, whereby conduction of said electrical signal indicates the presence of said change in said pressure differential.

A non-contact piezoelectric switch comprising:

• first and second conductors;
• a first snap action plate with an upwardly convex surface electrically connected to said first conductor;
• a second snap action plate with an upwardly convex surface electrically connected to said second conductor;
• a substantially disc-shaped piezoelectric polymer film having respective surfaces disposed between said upwardly convex surfaces of said first and second snap action plates;
• first and second substantially disc-shaped electrodes disposed on said respective surfaces of said piezoelectric polymer film;
• and
• an electrical insulator having a ring-like shape for insulating said first and second electrodes from said first and second snap action plates when neither of said snap action plates is in a depressed state,
• whereby upon depression of at least one of said snap action plates said first and second electrodes are brought into electrical contact with said first and second snap action plates and said piezoelectric polymer film is extended or contracted along the surface thereof so as to conduct an electrical signal between said first and second conductors via said first and second electrodes.

A non-contact piezoelectric switch comprising:

• first and second conductors;
• a first snap action plate with an upwardly convex surface electrically connected to said first conductor;
• a second snap action plate with an upwardly convex surface electrically connected to said second conductor;
• a piezoelectric polymer film having respective surfaces disposed between said upwardly convex surfaces of said first and second snap action plates;
• and
• first and second electrodes disposed on said respective surfaces of said piezoelectric polymer film, whereby said first and second snap action plates are depressed as a result of thermal expansion thereof when a predetermined temperature is exceeded, thereby extending or contracting said piezoelectric polymer film along the surface thereof so as to conduct an electrical signal between said first and second conductors via said first and second electrodes.

A non-contact piezoelectric switch comprising:

• a first disc-shaped snap action plate with a curved surface;
• a second disc-shaped snap action plate with a curved surface;
• a piezoelectric polymer film having respective surfaces disposed between said curved surfaces of said first and second snap action plates so as to electrically insulate said first and second snap action plates;
• first and second electrodes disposed on said respective surfaces of said piezoelectric polymer film so as to be respectively electrically coupled to said first and second snap action plates upon depression thereof, whereby upon such depression at least one of said snap action plates said piezoelectric polymer film is extended or contracted along the surface thereof so as to begin to conduct an electrical signal between said first and second snap action plates via said first and second electrodes;
• and
• a chamber having a fluid normally pressurized to a predetermined level, said first and second snap action plates being disposed across an opening in said chamber so as to be depressed by a change in a pressure differential between the inside and outside of said chamber, whereby conduction of said electrical signal indicates the presence of said change in said pressure differential.

A non-contact piezoelectric switch comprising:

• a first disc-shaped snap action plate with a curved surface;
• a second disc-shaped snap action plate with a curved surface;
• a piezoelectric polymer film having respective surfaces disposed between said curved surfaces of said first and second snap action plates so as to electrically insulate said first and second snap action plates;
• and
• first and second electrodes disposed on said respective surfaces of said piezoelectric polymer film so as to be respectively electrically coupled to said first and second snap action plates upon depression thereof, whereby said first and second snap action plates are depressed as a result of thermal expansion thereof when a predetermined temperature is exceeded, thereby extending or contracting said piezoelectric polymer film along the surface thereof so as to begin to conduct an electrical signal between said first and second snap action plates via said first and second electrodes.

A non-contact piezoelectric switch comprising:

• a first snap action plate with a curved surface;
• a second snap action plate with a curved surface;
• a substantially disc-shaped piezoelectric polymer film having respective surfaces disposed between said curved surfaces of said first and second snap action plates;
• first and second substantially disc-shaped electrodes disposed on said respective surfaces of said piezoelectric polymer film so as to conduct an electrical signal between said first and second snap action plates;
• and
• an insulator having a ring-like shape for electrically insulating said first and second electrodes from said first and second snap action plates when neither of said snap action plates is in a depressed state,
• whereby upon depression of at least one of said snap action plates said first and second electrodes are brought into electrical contact with said first and second snap action plates and said piezoelectric polymer film is extended or contracted along the surface thereof so as to conduct said electrical signal between said first and second snap action plates.