Self-powered switch initiation system

Patent metadata

Field	Value
Publication number	US-RE46499-E
Application number	US-39995409-A
Country	US
Kind code	E1
Filing date	Mar 8, 2009
Priority date	Jul 3, 2001
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A self-powered switching device using a prestressed flextensional electroactive member generates a signal for activation of a latching relay. The electroactive member has a piezoelectric element with a convex and a concave face that may be compressed to generate an electrical pulse. The flextensional electroactive member and associated signal generation circuitry can be hardwired directly to the latching relay or may be coupled to a transmitter for sending an RF signal to a receiver which actuates the latching relay.

First claim

We claim:

1. A self-powered switching system, comprising:
a flextensional transducer, said flextensional transducer comprising;
a first electroactive member having opposing first and second electroded major faces;
said first opposing electroded major face being substantially convex and said second opposing electroded major face being substantially concave;

a prestress layer bonded to said second electroded major face of said first electroactive member;
said prestress layer applying a compressive force to said first electroactive member;
said prestress layer having first and second ends adjacent said concave second electroded major face of said first electroactive member;

wherein
said flextensional transducer is adapted to deform from a first position to a second position upon application of a force to said flextensional transducer; and
and wherein upon said deformation to said second position, said flextensional transducer is adapted to generate a first voltage potential between said first electroded major face and said second electroded major face;

a mounting member for retaining said first end of said prestress layer;
said mounting member comprising:
a plate adjacent said first end of said prestress layer and said convex first electroded major face of said flextensional transducer;

said mounting member comprising clamping means adjacent said first end of said prestress layer and said concave second electroded major face of said flextensional transducer;
a recess defining a depressed surface in said plate, said depressed surface substantially conforming to at least a portion of said first electroded major face of said flextensional transducer adjacent said first end of said prestress layer and said first electroded major face of said electroactive member; and
a conductive sheet within said recess, said conductive sheet being in electrical contact with said first electroded major face of said first electroactive member and a first conductor electrically connected to said first electroded major face of said first electroactive member;

pressure application means for application of a force to said second end of said prestress layer, said pressure application means being adapted to apply a force sufficient to deform said flextensional transducer from said first position to said second position, thereby generating said first voltage potential;
a first conductor electrically connected to said first electroded major face of said first electroactive member;
a second conductor electrically connected to said second electroded major face of said first electroactive member;
first signal transmission means electrically connected to said first and second conductors;
said first signal transmission means comprising a first radio frequency generator subcircuit connected to an antenna;

signal reception means for receiving a first signal transmitted by said first signal transmission means;
said signal reception means being adapted to generate a second signal in response to said first signal transmitted by said signal transmission means; and

a switch having a first position and a second position;
said switch being in communication with said signal reception means; and
said switch being adapted to change between said first position and said second position in response to said second signal.

2. The switching system according to claim 1 :
wherein said mounting member further comprises a recess defining a depressed surface in said plate, said depressed surface substantially conforming to at least a portion of said convex face of said flextensional transducer adjacent said first end of said prestress layer and said major first electroded face of said electroactive member; and a conductive sheet within said recess, said conductive sheet being in electrical contact with said first electroded major face of said electroactive member and said first conductor.

3. The switching system according to claim 2 1:
wherein said mounting member further comprises a flexible material within said recess in said plate, said flexible material being between said depressed surface and said conductive sheet.

4. The switching system according to claim 3 , further comprising:
a voltage regulator having an input side and an output side;
said input side of said voltage regulator being electrically connected to said first and second conductors;
said output side of said voltage regulator being electrically connected to said signal transmission means.

5. The switching system according to claim 4 , further comprising:
a diode having an anode and a cathode connected in parallel with said flextensional transducer;
said cathode of said diode being electrically connected to said first conductor and said input side of said voltage regulator;
said anode of said diode being electrically connected to said second conductor and said input side of said voltage regulator;
whereby said diode is connected in parallel with first and second electroded major faces of said first electroactive member.

6. The switching system according to claim 5 , wherein said signal transmission means further comprises:
a tone generator subcircuit having an input side and an output side;
said input side of said tone generator subcircuit being connected to said output side of said voltage regulator;
said output side of said tone generator subcircuit being connected to said first radio frequency generator subcircuit.

7. The switching system according to claim 6 , wherein said tone generator subcircuit comprises:
an oscillator array having an input side and an output side;
said input side of said oscillator array being connected to said output side of said voltage regulator; and

a transistor having a grounded emitter and a base connected to said output side of said oscillator array;
and wherein said first radio frequency generator subcircuit comprises a resonant subcircuit having a first and a second junction;
said first junction of said resonant subcircuit being connected to said voltage regulator;
said second junction of said resonant subcircuit being connected to a collector of said transistor.

8. The switching system according to claim 7 , wherein said first radio frequency generator subcircuit further comprises:
a radio frequency choke connected in series between said output side of said voltage regulator and said first junction of said resonant subcircuit.

9. The switching device according to claim 8 , wherein said resonant subcircuit comprises:
a first capacitor having a first and a second plate; and
an inductive loop of a third conductor having first and second ends;
said first plate of said first capacitor being connected to said first end of said third conductor, thereby forming said first junction of said resonant subcircuit;
said second plate of said first capacitor being connected to said second end of said third conductor, thereby forming said second junction of said resonant subcircuit.

10. The switching system according to claim 9 , wherein said oscillator array further comprises an inverter array connected between said output side of said voltage regulator and said base of said transistor.

11. The switching system according to claim 10 , wherein said radio frequency choke comprises an inductor.

12. The switching system according to claim 11 , wherein said resonant subcircuit further comprises:
a tuning jumper comprising a sixth conductor having first and second ends each connected to said third conductor;
said tuning jumper being adapted to pivot at said first and second ends, thereby rotating relative to said third conductor.

13. The

Assignees

• Face Bradbury R
• Boyd Clark D
• Rogers Jr Glenn F
• Thomas Gregory P
• Face Int Corp

Inventors

• Face Bradbury R
• Boyd Clark D
• Rogers Jr Glenn F
• Thomas Gregory P

Classifications

• H01H35/00 Primary

  Switches operated by change of a physical condition (operated by change of magnetic or electric field H01H36/00; thermally-actuated switches H01H37/00) · CPC title

• Y02B90/20

  Smart grids as enabling technology in buildings sector (smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00) · CPC title

• Y04S20/14

  Protecting elements, switches, relays or circuit breakers · CPC title

• H03K2217/94089

  Wireless transmission · CPC title

• H03K17/964 Primary

  Piezoelectric touch switches · CPC title