Patent Publication Number: US-2017359066-A1

Title: Self-powered switch intitation system

Description:
This application is a Continuation of U.S. Continuation Reissue patent application Ser. No. 12/399,954, entitled “Self-Powered Switch Initiation System,” filed on Mar. 8, 2009 (now allowed), which is a Continuation Reissue Application of U.S. Reissue application Ser. No. 12/183,574, filed Jul. 31, 2008 (now abandoned), which is in turn a Reissue Application of U.S. Pat. No. 7,084,529 B2, issued on Aug. 1, 2006 from U.S. patent application Ser. No. 10/188,633, filed Jul. 3, 2002, which claims the benefit of U.S. Provisional Patent Application No. 60/302,990, filed Jul. 3, 2001, the disclosures of which are hereby incorporated by reference herein in their entirety. This application is related to U.S. patent application Ser. No. [Attorney Docket No. 020-028], entitled “Self-Powered Switch Initiation System,” filed on a same day as this application, the disclosure of which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates generally to switching devices for energizing lights, appliances and the like. More particularly, the present invention relates to a self-powered switch initiator device to generate an activation signal for a latching relay. The power is generated through a piezoelectric element and is sent through signal generation circuitry coupled to a transmitter for sending RF signal (which may be unique and/or coded) to one or more receivers that actuate the latching relay. The receivers are also trainable to respond to multiple transmitters. 
     2. Description of the Prior Art 
     Switches and latching relays for energizing lights, appliances and the like are well known in the prior art. Typical light switches comprise, for example, single-pole switches and three-way switches. A single-pole switch has two terminals that are hot leads for an incoming line (power source) and an outgoing line to the light. Three-way switches can control one light from two different places. Each three-way switch has three terminals: the common terminal and two traveler terminals. A typical pair of three-way switches uses two boxes each having two cables with the first box having an incoming line from a power source and an outbound line to the second box, and the second box having the incoming line from the first box and an outbound line to the light. 
     In each of these switching schemes it is often necessary to drill holes and mount switches and junction boxes for the outlets as well as running cable. Drilling holes and mounting switches and junction boxes can be difficult and time consuming. Also, running electrical cable requires starting at a fixture, pulling cable through holes in the framing to each fixture in the circuit, and continuing all the way back to the service panel. Though simple in theory, getting cable to cooperate can be difficult and time consuming. Cable often kinks, tangles or binds while pulling, and needs to be straightened out somewhere along the run. 
     Remotely actuated switches/relays are also known in the art. Known remote actuation controllers include tabletop controllers, wireless remotes, timers, motion detectors, voice activated controllers, and computers and related software. For example, remote actuation means may include modules that are plugged into a wall outlet and into which a power cord for a device may be plugged. The device can then be turned on and off by a controller. Other remote actuation means include screw-in lamp modules wherein the module is screwed into a light socket, and then a bulb screwed into the module. The light can be turned on and off and can be dimmed or brightened by a controller. 
     An example of a typical remote controller for the above described modules is a radio frequency (RF) base transceiver. With these controllers, a base is plugged into an outlet and can control groups of modules in conjunction with a hand held wireless RF remote. RF repeaters may be used to boost the range of compatible wireless remotes, switches and security system sensors by up to 150 ft. per repeater. The base is required for all wireless RF remotes and allows control of several lamps or appliances. Batteries are also required in the hand held wireless remote. 
     Rather than using a hand held RF remote, remote wall switches may be used. These wall switches, which are up to ¾″ thick, are affixed to a desired location with an adhesive. In conjunction with a base unit (plugged into a 110V receptacle) the remote wall switch may control compatible modules or switches (receivers). The wireless switches send an RF signal to the base unit and the base unit then transmits a signal along the existing 110V wiring in the home to compatible switches or modules. Each switch can be set with an addressable signal. Wireless switches also require batteries. 
     These remotes control devices may also control, for example, audio/video devices such as the TV, VCR, and stereo system, as well as lights and other devices using an RF to infrared (IR) base. The RF remote can control audio/video devices by sending proprietary RF commands to a converter that translates the commands to IR. IR commands are then sent to the audio/video equipment. The console responds to infrared signals from the infrared remotes and then transmits equivalent commands to compatible receivers. 
     A problem with conventional wall switches is that extensive wiring must be run both from the switch boxes to the lights and from the switch boxes to the power source in the service panels. 
     Another problem with conventional wall switches is that additional wiring must be run for lights controlled by more than one switch. 
     Another problem with conventional wall switches is that the high voltage lines are present as an input to and an output from the switch. 
     Another problem with conventional wall switches is the cost associated with initial installation of wire to, from and between switches. 
     Another problem with conventional wall switches is the cost and inconvenience associated with remodeling, relocating or rewiring existing switches. 
     A problem with conventional RF switches is that they require an external power source such as high voltage AC power or batteries. 
     Another problem with conventional RF switches is the cost and inconvenience associated with replacement of batteries. 
     Another problem with conventional RF switches is that they require high power to individual modules and base units. 
     Another problem with conventional AC-powered RF switches is the difficulty when remodeling in rewiring or relocating a wall switch. 
     Another problem with conventional RF switches is that a pair comprising a transmitter and receiver must generally be purchased together. 
     Another problem with conventional RF switches is that transmitters may inadvertently activate incorrect receivers. 
     Another problem with conventional RF switches is that receivers may accept an activation signal from only one transmitter. 
     Another problem with conventional RF switches is that transmitters may activate only one receiver. 
     Accordingly, it would be desirable to provide a network of switch initiators and/or latching relay devices that overcomes the aforementioned problems of the prior art. 
     SUMMARY 
     The present invention provides a self-powered switching initiator or latching relay device using an electroactive or electromagnetic actuator. The piezoelectric element in the electroactive actuator is capable of deforming with a high amount of axial displacement, and when deformed by a mechanical impulse generates an electric field. In an electromagnetic device, the relative motion between a magnet and a series of coils develops the electrical signal. The electroactive actuator is used as an electromechanical generator for generating a momentary signal that initiates a latching or relay mechanism. The latching or relay mechanism thereby turns electrical devices such as lights and appliances on and off or provides an intermediate or dimming signal. 
     The mechanical actuating means for the electroactive actuator element applies a suitable mechanical impulse to the electroactive actuator element in order to generate an electrical signal, such as a pulse or wave having sufficient magnitude and duration to actuate downstream circuit components. A switch similar to a light switch, for example, may apply pressure through a toggle, snap action, paddled or plunger mechanism. Larger or multiple electroactive actuator elements may also be used to generate the electrical signal. Copending application Ser. No. 09/616,978 entitled “Self-Powered Switching Device,” which is hereby incorporated by reference, discloses a self-powered switch where the electroactive element generates an electrical pulse. Copending provisional application 60/252,228 entitled “Self-Powered Trainable Switching Network,” which is hereby incorporated by reference, discloses a network of switches such as that disclosed in the application Ser. No. 09/616,978, with the modification that the switches and receivers are capable accepting a multiplicity of coded RF signals. In the present invention, a modification has been developed to the mechanical actuation of the electroactive element resulting in a modification of the type of electrical signal produced by the actuator. The present invention describes a self-powered switch initiator having an electroactive element and accompanying circuitry designed to work with an oscillating electrical signal. To harness the power generated by the electroactive element, the accompanying RF signal generation circuitry has also been modified to use the electrical signal most efficiently. 
     In one embodiment of the invention, the electroactive actuator is depressed by the manual or mechanical actuating means and the oscillating electrical signal generated by the electroactive actuator is applied to the relay or switch through circuitry designed to modify the electrical signal. In yet another embodiment, the electromagnetic or electroactive actuator signal powers an RF transmitter which sends an RF signal to an RF receiver which then actuates the relay. In yet another embodiment, the electromagnetic or electroactive actuator signal powers a transmitter, which sends a pulsed RF signal to an RF receiver which then actuates the relay. Digitized RF signals may be coded (as with a garage door opener) to only activate the relay that is coded with that digitized RF signal. The transmitters may be capable of developing one or more coded RF signals and the receivers likewise may be capable of receiving one or more coded RF signal. Furthermore, the receivers may be “trainable” to accept coded RF signals from new or multiple transmitters. 
     Accordingly, it is a primary object of the present invention to provide a switching or relay device in which an electroactive or piezoelectric element is used to activate the device. 
     It is another object of the present invention to provide a device of the character described in which switches may be installed without necessitating additional wiring. 
     It is another object of the present invention to provide a device of the character described in which switches may be installed without cutting holes into the building structure. 
     It is another object of the present invention to provide a device of the character described in which switches do not require external electrical input such as 120 or 220 VAC or batteries. 
     It is another object of the present invention to provide a device of the character described incorporating an electroactive device that generates an electrical signal of sufficient magnitude and duration to activate a latching relay and/or switch initiator. 
     It is another object of the present invention to provide a device of the character described incorporating an electroactive that generates an electrical signal of sufficient duration and magnitude to activate a radio frequency transmitter for activating a latching relay and/or switch initiator. 
     It is another object of the present invention to provide a device of the character described incorporating an actuator that generates an electrical signal of sufficient magnitude to activate a radio frequency transmitter for activating a latching relay and/or switch initiator. 
     It is another object of the present invention to provide a device of the character described incorporating a transmitter that is capable of developing at least one coded RF signal. 
     It is another object of the present invention to provide a device of the character described incorporating a receiver capable of receiving at least one coded RF signal from at least one transmitter. 
     It is another object of the present invention to provide a device of the character described incorporating a receiver capable of “learning” to accept coded RF signals from one or more transmitters. 
     It is another object of the present invention to provide a device of the character described for use in actuating lighting, appliances, security devices and other fixtures in a building. 
     Further objects and advantages of the invention will become apparent from a consideration of the drawings and ensuing description thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an elevation view showing the details of construction of a flextensional piezoelectric actuator used in the present invention; 
         FIG. 1 a    is an elevation view showing the details of construction of the flextensional piezoelectric actuator of  FIG. 1  having an additional prestress layer; 
         FIG. 2  is an elevation view showing the details of construction of an alternate multi-layer flextensional piezoelectric actuator used in a modification the present invention; 
         FIG. 3  is an elevation view of an embodiment of a device for mechanical application and removal of a force to the center of an actuator; 
         FIG. 4  is an elevation view of the device of  FIG. 3  illustrating the deformation of the actuator upon application of a force; 
         FIG. 5  is an elevation view of the device of  FIG. 3  illustrating the recovery of the actuator upon removal of the force by tripping of a quick-release device; 
         FIG. 6  is an elevation view of the actuating device of the present invention for generation of an electrical signal by deflecting a flextensional piezoelectric actuator; 
         FIG. 7  is an elevation view of the preferred actuating device of the present invention for generation of an electrical signal by deflecting a flextensional piezoelectric actuator; 
         FIG. 8  is a block diagram showing the components of a circuit for using the electrical signal generated by the device of  FIG. 6 or 7 ; 
         FIG. 9  a detailed circuit diagram of the circuit in  FIG. 8 ; 
         FIGS. 10 a - c    show the electrical signal generated by the actuator, the rectified electrical signal and the regulated electrical signal respectively; 
         FIG. 11  is a plan view of a tuned loop antenna of  FIG. 8  illustrating the jumper at a position maximizing the inductor cross-section; 
         FIG. 12  is a plan view of the tuned loop antenna of  FIG. 8  illustrating the jumper at a position minimizing the inductor cross-section; 
         FIG. 13  is an elevation view of a preferred deflector assembly and casing which enclose the actuator of the present invention; 
         FIG. 14  is an elevation view of an alternate embodiment a deflector assembly using a sliding paddle; 
         FIGS. 15 a - c    are elevational cross-sections taken along line  15 - 15  of  FIG. 13  showing the preferred embodiment of a casing and deflector assembly using a quick release mechanism; and 
         FIGS. 16 a - d    are elevational cross-sections taken along line  16 - 16  of  FIG. 14 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Electroactive Actuator 
     Piezoelectric and electrostrictive materials (generally called “electroactive” devices herein) develop a polarized electric field when placed under stress or strain. The electric field developed by a piezoelectric or electrostrictive material is a function of the applied force causing the mechanical stress or strain. Conversely, electroactive devices undergo dimensional changes in an applied electric field. The dimensional change (i.e., expansion or contraction) of an electroactive device is a function of the applied electric field. Electroactive devices are commonly used as drivers, or “actuators” due to their propensity to deform under such electric fields. These electroactive devices or actuators also have varying capacities to generate an electric field in response to a deformation caused by an applied force. 
     Electroactive devices include direct and indirect mode actuators, which typically make use of a change in the dimensions of the material to achieve a displacement, but in the present invention are preferably used as electromechanical generators. Direct mode actuators typically include a piezoelectric or electrostrictive ceramic plate (or stack of plates) sandwiched between a pair of electrodes formed on its major surfaces. The devices generally have a sufficiently large piezoelectric and/or electrostrictive coefficient to produce the desired strain in the ceramic plate. However, direct mode actuators suffer from the disadvantage of only being able to achieve a very small displacement (strain), which is, at best, only a few tenths of a percent. Conversely, direct mode generator-actuators require application of a high amount of force to piezoelectrically generate a pulsed momentary electrical signal of sufficient magnitude to activate a latching relay. 
     Indirect mode actuators are known to exhibit greater displacement and strain than is achievable with direct mode actuators by achieving strain amplification via external structures. An example of an indirect mode actuator is a flextensional transducer. Flextensional transducers are composite structures composed of a piezoelectric ceramic  32  element and a metallic shell, stressed plastic, fiberglass, or similar structures. The actuator movement of conventional flextensional devices commonly occurs as a result of expansion in the piezoelectric material which mechanically couples to an amplified contraction of the device in the transverse direction. In operation, they can exhibit several orders of magnitude greater strain and displacement than can be produced by direct mode actuators. 
     The magnitude of achievable strain of indirect mode actuators can be increased by constructing them either as “unimorph” or “bimorph” flextensional actuators. A typical unimorph is a concave structure composed of a single piezoelectric element externally bonded to a flexible metal foil, and which results in axial buckling or deflection when electrically energized. Common unimorphs can exhibit a strain of as high as 10%. A conventional bimorph device includes an intermediate flexible metal foil sandwiched between two piezoelectric elements. Electrodes are bonded to each of the major surface of the ceramic elements and the metal foil is bonded to the inner two electrodes. Bimorphs exhibit more displacement than comparable unimorphs because under the applied voltage, one ceramic element will contract while the other expands. Bimorphs can exhibit strains up to 20%. 
     For certain applications of electroactive actuators, asymmetrically stress biased electroactive devices have been proposed in order to increase the axial deformation of the electroactive material, and therefore increase the achievable strain of the electroactive material. In such devices, (which include, for example, “Rainbow” actuators (as disclosed in U.S. Pat. No. 5,471,721), and other flextensional actuators) the asymmetric stress biasing produces a curved structure, typically having two major surfaces, one of which is concave and the other which is convex. 
     Referring to  FIG. 1 : A unimorph actuator called “THUNDER”, which has improved displacement, strain and load capabilities, has recently been developed and is disclosed in U.S. Pat. No. 5,632,841. THUNDER (which is an acronym for THin layer composite UNimorph ferroelectric Driver and sEnsoR), is a unimorph actuator in which a pre-stress layer is bonded to a thin piezoelectric ceramic wafer at high temperature, and during the cooling down of the composite structure asymmetrically stress biases the ceramic wafer due to the difference in thermal contraction rates of the pre-stress layer and the ceramic layer. 
     The THUNDER actuator  12  is as a composite structure, the construction of which is illustrated in  FIG. 1 . Each THUNDER actuator  12  is constructed with an electroactive member preferably comprising a piezoelectric ceramic layer  67  of PZT which is electroplated  65  and  65   a  on its two opposing faces. A pre-stress layer  64 , preferably comprising spring steel, stainless steel, beryllium alloy or other metal substrate, is adhered to the electroplated  65  surface on one side of the ceramic layer  67  by a first adhesive layer  66 . In the simplest embodiment, the adhesive layer  66  acts as a prestress layer. The first adhesive layer  66  is preferably LaRC™-SI material, as developed by NASA-Langley Research Center and disclosed in U.S. Pat. No. 5,639,850. A second adhesive layer  66   a , also preferably comprising LaRC-SI material, is adhered to the opposite side of the ceramic layer  67 . During manufacture of the THUNDER actuator  12  the ceramic layer  67 , the adhesive layer(s)  66  and  66   a  and the pre-stress layer  64  are simultaneously heated to a temperature above the melting point of the adhesive material. In practice the various layers composing the THUNDER actuator (namely the ceramic layer  67 , the adhesive layers  66  and  66   a  and the pre-stress layer  64 ) are typically placed inside of an autoclave or a convection oven as a composite structure, and slowly heated by convection until all the layers of the structure reach a temperature which is above the melting point of the adhesive  66  material but below the Curie temperature of the ceramic layer  67 . It is desirable to keep the temperature of the ceramic layer  67  beneath the Curie temperature of the ceramic layer in order to avoid disrupting the piezoelectric characteristics of the ceramic layer  67 . Because the multi-layer structure is typically convectively heated at a slow rate, all of the layers tend to be at approximately the same temperature. In any event, because an adhesive layer  66  is typically located between two other layers (i.e. between the ceramic layer  67  and the pre-stress layer  64 ), the ceramic layer  67  and the pre-stress layer  64  are usually very close to the same temperature and are at least as hot as the adhesive layers  66  and  66   a  during the heating step of the process. The THUNDER actuator  12  is then allowed to cool. 
     During the cooling step of the process (i.e. after the adhesive layers  66  and  66   a  have re-solidified) the ceramic layer  67  becomes compressively stressed by the adhesive layers  66  and  66   a  and pre-stress layer  64  due to the higher coefficient of thermal contraction of the materials of the adhesive layers  66  and  66   a  and the pre-stress layer  64  than for the material of the ceramic layer  67 . Also, due to the greater thermal contraction of the laminate materials (e.g. the first pre-stress layer  64  and the first adhesive layer  66 ) on one side of the ceramic layer  67  relative to the thermal contraction of the laminate material(s) (e.g. the second adhesive layer  66   a ) on the other side of the ceramic layer  67 , the ceramic layer deforms in an arcuate shape having a normally convex face  12   a  and a normally concave face  12   c , as illustrated in  FIGS. 1 and 2 . 
     Referring to  FIG. 1 a   : One or more additional pre-stressing layer(s) may be similarly adhered to either or both sides of the ceramic layer  67  in order, for example, to increase the stress in the ceramic layer  67  or to strengthen the actuator  12 B. In a preferred embodiment of the invention, a second prestress layer  68  is placed on the concave face  12   a  of the actuator  12 B having the second adhesive layer  66   a  and is similarly heated and cooled. Preferably the second prestress layer  68  comprises a layer of conductive metal. More preferably the second prestress layer  68  comprises a thin foil (relatively thinner than the first prestress layer  64 ) comprising aluminum or other conductive metal. During the cooling step of the process (i.e. after the adhesive layers  66  and  66   a  have re-solidified) the ceramic layer  67  similarly becomes compressively stressed by the adhesive layers  66  and  66   a  and pre-stress layers  64  and  68  due to the higher coefficient of thermal contraction of the materials of the adhesive layers  66  and  66   a  and the pre-stress layers  64  and  68  than for the material of the ceramic layer  67 . Also, due to the greater thermal contraction of the laminate materials (e.g. the first prestress layer  64  and the first adhesive layer  66 ) on one side of the ceramic layer  67  relative to the thermal contraction of the laminate material(s) (e.g. the second adhesive layer  66   a  and the second prestress layer  68 ) on the other side of the ceramic layer  67 , the ceramic layer  67  deforms into an arcuate shape having a normally convex face  12   a  and a normally concave face  12   c , as illustrated in  FIG. 1   a.    
     Alternatively, the substrate comprising a separate prestress layer  64  may be eliminated and the adhesive layers  66  and  66   a  alone or in conjunction may apply the prestress to the ceramic layer  67 . Alternatively, only the prestress layer(s)  64  and  68  and the adhesive layer(s)  66  and  66   a  may be heated and bonded to a ceramic layer  67 , while the ceramic layer  67  is at a lower temperature, in order to induce greater compressive stress into the ceramic layer  67  when cooling the actuator  12 . 
     Referring now to  FIG. 2 : Yet another alternate actuator  12 D includes a composite piezoelectric ceramic layer  69  that comprises multiple thin layers  69   a  and  69   b  of PZT which are bonded to each other. Each layer  69   a  and  69   b  comprises a thin layer of piezoelectric material, with a thickness preferably on the order of about 1 mil. Each thin layer  69   a  and  69   b  is electroplated  65  and  65   a , and  65   b  and  65   c  on each major face respectively. The individual layers  69   a  and  69   b  are then bonded to each other with an adhesive layer  66   b , using an adhesive such as LaRC-SI. Alternatively, and most preferably, the thin layers  69   a  and  69   b  may be bonded to each other by cofiring the thin sheets of piezoelectric material together. As few as two layers  69   a  and  69   b , but preferably at least four thin sheets of piezoelectric material may be bonded/cofired together. The composite piezoelectric ceramic layer  69  may then be bonded to prestress layer(s)  64  with the adhesive layer(s)  66  and  66   a , and heated and cooled as described above to make a modified THUNDER actuator  12 D. By having multiple thinner layers  69   a  and  69   b  of piezoelectric material in a modified actuator  12 D, the composite ceramic layer generates a lower voltage and higher current as compared to the high voltage and low current generated by a THUNDER actuator  12  having only a single thicker ceramic layer  67 . 
     A flexible insulator may be used to coat the convex face  12   a  of the actuator  12 . This insulative coating helps prevent unintentional discharge of the piezoelectric element through inadvertent contact with another conductor, liquid or human contact. The coating also makes the ceramic element more durable and resistant to cracking or damage from impact. Since LaRC-SI is a dielectric, the adhesive layer  67   a  on the convex face  12   a  of the actuator  12  may act as the insulative layer. Alternately, the insulative layer may comprise a plastic, TEFLON or other durable coating. 
     Electrical energy may be recovered from or introduced to the actuator element  12  by a pair of electrical wires  14 . Each electrical wire  14  is attached at one end to opposite sides of the actuator element  12 . The wires  14  may be connected (for example by glue or solder  20 ) directly to the electroplated  65  and  65   a  faces of the ceramic layer  67 , or they may alternatively be connected to the pre-stress layer(s)  64 . As discussed above, the prestress layer  64  is preferably adhered to the ceramic layer  67  by LaRC-SI material, which is a dielectric. When the wires  14  are connected to the pre-stress layer(s)  64 , it is desirable to roughen a face of the pre-stress layer  64 , so that the pre-stress layer  64  intermittently penetrates the respective adhesive layers  66  and  66   a , and make electrical contact with the respective electroplated  65  and  65   a  faces of the ceramic layer  67 . Alternatively, the Larc-SI adhesive layer  66  may have a conductive material, such as Nickel or aluminum particles, used as a filler in the adhesive and to maintain electrical contact between the prestress layer and the electroplated face of the ceramic. The opposite end of each electrical wire  14  is preferably connected to an electric pulse modification circuit  10 . 
     Prestressed flextensional transducers  12  are desirable due to their durability and their relatively large displacement, and concomitant relatively high voltage that such transducers are capable of developing. The present invention however may be practiced with any electroactive element having the properties and characteristics herein described, i.e., the ability to generate a voltage in response to a deformation of the device. For example, the invention may be practiced using magnetostrictive or ferroelectric devices. The transducers also need not be normally arcuate, but may also include transducers that are normally flat, and may further include stacked piezoelectric elements. 
     In operation, as shown in  FIG. 4 , when a force indicated by arrow  16  is applied to the convex face  12   a  of the actuator  12 , the force deforms the piezoelectric element  67 . The force may be applied to the piezoelectric actuator  12  by any appropriate means such as by application of manual pressure directly to the piezoelectric actuator, or by other mechanical means. Preferably, the force is applied by a mechanical switch (e.g., a plunger, striker, toggle or roller switch) capable of developing a mechanical impulse for application to and removal from the actuator  12 . The mechanical impulse (or removal thereof) is of sufficient force to cause the actuator  12  to deform quickly and accelerate over a distance (approximately 10 mm) which generates an electrical signal of sufficient magnitude to activate an electromechanical latching relay. 
     Referring to  FIGS. 3, 4 and 5 : An illustration of prior means generating an electrical pulse by application of mechanical force comprises a switch plate  18  and a plunger assembly  13 . The two ends of the piezoelectric actuator are each pivotably held in place within a recess  44  of a switch plate  18 . The switch plate  18  is the same shape as the actuator  12  contained therein, preferably rectangular. Alternatively, a circular actuator is mounted in a circular recess of a circular switch plate. The recess(es)  44  in the switch plate  18  hold the actuator  12  in place in its relaxed, i.e., undeformed state. The recesses  44  are also sufficiently deep to fully receive the ends or edges of the actuator  12  in its fully deformed, i.e., flat state. The plunger assembly comprises a push button  22  pivotably connected to a hinged quick-release mechanism  24 . The opposite end of the quick-release mechanism  24  contacts shaft  26  connected to a pair of plates  27  and  28  which are clamped on both sides of the actuator  12 . A release cog  25  is located along the path of the quick-release mechanism  24 . 
     In operation, when the push button  22  is depressed in the direction of arrow  16 , the quick-release mechanism  24  pushes down on the shaft  26  and plates  27  and  28  and deforms the actuator  12 . When the quick-release mechanism  24  reaches the release cog  25 , the quick-release mechanism  24  pivots on its hinge and releases the downward pressure from the shaft  26 , plates  27  and  28  and actuator  12 . The actuator  12 , on account of the restoring force of the substrate of the prestress layer  64 , returns quickly to its undeformed state in the direction of arrow  30  as in  FIG. 5 . 
     As previously mentioned, the applied force causes the piezoelectric actuator  12  to deform. By virtue of the piezoelectric effect, the deformation of the piezoelectric element  67  generates an instantaneous voltage between the faces  12   a  and  12   c  of the actuator  12 , which produces a pulse of electrical energy. Furthermore, when the force is removed from the piezoelectric actuator  12 , the actuator  12  recovers its original arcuate shape. This is because the substrate or prestress layers  64  and  68  to which the ceramic  67  is bonded exert a compressive force on the ceramic  67 , and the actuator  12  thus has a coefficient of elasticity that causes the actuator  12  to return to its undeformed neutral state. On the recovery stroke of the actuator  12 , the ceramic  67  returns to its undeformed state and thereby produces another electrical pulse of opposite polarity. The downward (applied) or upward (recovery) strokes should cause a force over a distance that is of sufficient magnitude to create the desired electrical pulse. The duration of the recovery stroke, and therefore the duration of the pulse produced, is preferably in the range of 50 100 milliseconds, depending on the amount of force applied to the actuator  12 . 
     Referring to  FIG. 6 : In the preferred embodiment of the invention, the actuator  12  is clamped at one end  121  and the mechanical impulse is applied to the edge on the free end  122 , i.e., at the end opposite to the clamped end  121  of the actuator  12 . By applying the force to the edge on the free end  122  of the actuator  12  and releasing it, the electrical pulse that is generated upon removal of the force is an oscillating wave rather than a single pulse as in the prior actuating means disclosed above. 
     Referring again to  FIG. 6 :  FIG. 6  illustrates one embodiment of a device for generating an electrical pulse by application of mechanical force to an end of the actuator  12 . This device comprises an actuator  12  mounted between a base plate  70  and a clamping member  75  as well as a deflector assembly  72 . The base plate  70  is preferably of substantially the same shape (in plan view) as the actuator  12  attached thereon, and most preferably rectangular. One end  121  of the piezoelectric actuator  12  is held in place between the clamping member  75  and the upper surface  70   a  of a base plate  70 , preferably on one end thereof. The clamping member  75  comprises a plate or block having a lower surface  75   a  designed to mate with the upper surface  70   a  of the base plate  70  with the actuator  12  therebetween. The device also has means for urging  76  the mating surface  75   a  of the clamping block towards the upper surface  70   a  of the base plate  70 . This allows the lower surface  75   a  of the clamping plate  75  to be substantially rigidly coupled to the upper surface  70   a  of the base plate  70 , preferably towards one side of the switch plate  70 . The means for urging  76  together the mating surfaces  70   a  and  75   a  of the base plate  70  and clamping plate  75  may comprise screws, clamping jaws or springs or the like. Most preferably the urging means  76  comprises at least one screw  76  passing through the clamping member  75  and into a screw hole  77  in the upper surface  70   a  of the base plate  70 . 
     One end  121  of an actuator  12  is placed between the mating surfaces  70   a  and  75   a  of the base and clamping plates  70  and  75 . The mating surfaces  70   a  and  75   a  are then urged towards each other with the screw  76  to rigidly hold the end  121  of the actuator  12  in place between the base and clamping plates  70  and  75  with the opposite end  122  of the actuator  12  free to be moved by a mechanical impulse applied manually or preferably by a deflector assembly  72 . 
     Referring now to  FIG. 7 : In the preferred embodiment of the invention the surfaces  70   a  and  75   a  of the base and clamping plate  70  and  75  are designed to best distribute pressure evenly along the end  121  of the actuator therebetween. To this end the upper surface  70   a  of the base plate  70  contacting the end  121  of the actuator is preferably substantially flat and lower surface  75   a  of the clamping member  75  preferably has a recess  74  therein which accommodates insertion of the actuator end  121  therein. Preferably the depth of the recess  74  is equal to half the thickness of the actuator substrate  64 , but may be as deep as the substrate thickness. Thus, the end  121  of the actuator  12  may be placed between the recess  74  and the upper surface  70   a  of the base plate  70  and secured therebetween by the screw  76 . Alternatively, either or both of the mating surfaces  70   a  and  75   a  of the base and clamping plates  70  and  75  may have a recess therein to accommodate insertion and retention of the end  121  of the actuator  12  therebetween. The portion of the bottom surface  75   a  of the clamping member  75  beyond the recess  74  has no contact with the actuator  12 , and is that portion through which the screw  76  passes. This portion of the bottom surface  75   a  may contact the upper surface  70   a  of the base plate  70 , but most preferably there is a small gap (equal to the difference of the substrate thickness and the recess depth) between the lower surface  75   a  of the clamping member  75  and the top surface  70   a  of the base plate  70  when the actuator  12  is inserted therebetween. In yet another embodiment of the invention, the mating surfaces  70   a  and  75   a  of the base and clamping plates  70  and  75  may be adhesively bonded together (rather than screwed) with the end  121  of the actuator  12  sandwiched therebetween. In yet another alternative embodiment of the device, the clamping member  75  and base plate  70  may comprise a single molded structure having a central slot into which may be inserted one end  121  of the actuator  12 . 
     The clamping assembly  75  holds the actuator  12  in place in its relaxed, i.e., undeformed state above the base plate  70  with the free end  122  of the actuator  12  in close proximity to a deflector  72  assembly. More specifically, the actuator  12  is preferably clamped between the mating surfaces  70   a  and  75   a  of the base and clamping plates  70  and  75  with the convex face  12   a  of the actuator  12  facing the base plate  70 . Since the actuator  12  in its relaxed state is arcuate, the convex face  12   a  of the actuator  12  curves away from the upper surface  70   a  of the base plate  70  while approaching the free end  122  of the actuator  12 . Mechanical force may then be applied to the free end  122  of the actuator  12  in order to deform the electroactive element  67  to develop an electrical signal. 
     Because of the composite, multi-layer construction of the actuator  12  it is important to ensure that the clamping member  75  not only holds the actuator  12  rigidly in place, but also that the actuator  12  is not damaged by the clamping member  75 . In other words, the actuator  12 , and more specifically the ceramic layer  67 , should not be damaged by the clamping action of the clamping member  75  in a static mode, but especially in the dynamic state when applying a mechanical impulse to the actuator  12  with the plunger  72 . For example, referring to  FIG. 6 , when a mechanical impulse is applied to the actuator  12  in the direction of arrow  81 , the bottom corner of the ceramic (at point C) contacts the base plate  70  and is further pushed into the base plate, which may crack or otherwise damage the ceramic layer  67 . 
     Referring again to  FIG. 7 : It has been found that the tolerances between the mating surfaces  75   a  and  70   a  of the clamping and base plates  75  and  70  are very narrow. It has also been found that application of a downward force (as indicated by arrow  81 ) to the free end  122  of the actuator  12  would cause the ceramic element  67  of the actuator  12  to contact the upper surface  70   a  of the base plate  70 , thereby making more likely damage to the ceramic  67 . Therefore, in the preferred embodiment of the invention, the switch plate  70  has a recessed area  80  in its upper surface  70   a  which not only protects the electroactive element  67  from damage but also provides electrical contact to the convex face  12   a  of the actuator  12  so that the electrical signal developed by the actuator  12  may be applied to downstream circuit elements. 
     As can be seen in  FIG. 7 , one end  121  of the actuator is placed between the surfaces  75   a  and  70   a  of the clamping and base plates  75  and  70  such that only the substrate  64  contacts both surface  75   a  and  70   a . The clamping plate  75  preferably contacts the concave surface  12   b  of the actuator  12  along the substrate  64  up to approximately the edge of the ceramic layer  67  on the opposite face  12   a  of the actuator  12 . The clamping member may however extend along the convex face  12   c  further than the edge C of the ceramic layer  67  in order to apply greater or more even pressure to the actuator surfaces  12   a  and  12   c  between the clamping member  75  and base plate  70 . The ceramic layer  67  which extends above the surface of the substrate  64  on the convex face  12   a  extends into the recessed area  80  of the switch plate  70 . This prevents the ceramic layer  67  from contacting the upper surface  70   a  of the base plate  70 , thereby reducing potential for damage to the ceramic layer  67 . 
     The recess  80  is designed not only to prevent damage to the ceramic layer  67 , but also to provide a surface along which electrical contact can be maintained with the electrode  68  on the convex face of the actuator  12 . The recess  80  extends into the base plate  70  and has a variable depth, preferably being angled to accommodate the angle at which the convex face  12   a  of the actuator  12  rises from the recess  80  and above the top surface  70   a  of the base plate  70 . More specifically, the recess  80  preferably has a deep end  81  and a shallow end  82  with its maximum depth at the deep end  81  beneath the clamping member  75  and substrate  12  just before where the ceramic layer  67  extends into the recess  80  at point C. The recess  80  then becomes shallower in the direction approaching the free end  122  of the actuator  12  until it reaches its minimum depth at the shallow end  82 . 
     The recess  80  preferably contains a layer of rubber  85  along its lower surface which helps prevent the ceramic layer  67  from being damaged when the actuator  12  is deformed and the lower edge C of the ceramic layer  67  is pushed into the recess  80 . Preferably the rubber layer  85  is of substantially uniform thickness along its length, the thickness of the rubber layer  85  being substantially equal to the depth of the recess  80  at the shallow end  82 . The length of the rubber layer  85  is preferably slightly shorter than the length of the recess  80  to accommodate the deformation of the rubber layer  85  when the actuator  12  is pushed into the recess and rubber layer  85 . 
     The rubber layer  85  preferably has a flexible electrode layer  90  overlying it to facilitate electrical contact with the aluminum layer  68  on the ceramic layer  67  on the convex face  12   a  of the actuator  12 . More preferably, the electrode layer  90  comprises a layer of copper overlaying a layer of KAPTON film, as manufactured by E.I. du Pont de Nemours and Company, bonded to the rubber layer  85  with a layer of adhesive, preferably CIBA adhesive. The electrode layer  90  preferably extends completely across the rubber layer  85  from the deep end  81  to the shallow end  82  of the recess  80  and continues for a short distance on the top surface  70   a  of the base plate  70  beyond the recess  80 . 
     In the preferred embodiment of the invention, the end  121  of the actuator  12  is not only secured between the clamping plate  75  and the base plate  70 , but the aluminum electrode layer  68  covering the ceramic layer  67  of the actuator  12  is in constant contact with the electrode layer  90  in the recess  80  at all times, regardless of the position of the actuator  12  in its complete range of motion. To this end, the depth of the recess  80  (from the top surface  70   a  to the electrode  90 ) is at least equal to a preferably slightly less than the thickness of the laminate layers (adhesive layers  66 , ceramic layer  67  and prestress layer  68 ) extending into the recess  80 . 
     An assembly was built having the following illustrative dimensions. The actuator comprised a 1.59 by 1.79 inch spring steel substrate that was 8 mils thick. A 1 1.5 mil thick layer of adhesive having a nickel dust filler in a 1.51 inch square was placed one end of the substrate 0.02 inch from three sides of the substrate (leaving a 0.25 inch tab on one end  121  of the actuator). An 8-mil thick layer of PZT-5A in a 1.5 inch square was centered on the adhesive layer. A 1-mil thick layer of adhesive (with no metal filler) was placed in a 1.47 inch square centered on the PZT layer. Finally, a 1-mil thick layer of aluminum in a 1.46 inch square was centered on the adhesive layer. The tab  121  of the actuator was placed in a recess in a clamping block  76  having a length of 0.375 inch and a depth of 4 mils. The base plate  70  had a 0.26 in long recess  80  where the deep end  81  of the recess had a depth of 20 mils and tapered evenly to a depth of 15 mils at the shallow end  82  of the recess  80 . A rubber layer  85  having a thickness of 15 mils and a length of 0.24 inches was placed in the recess  80 . An electrode layer of 1 mil copper foil overlying 1 mil KAPTON tape was adhered to the rubber layer and extended beyond the recess 1.115 inches. The clamping member  75  was secured to the base plate  70  with a screw  76  and the aluminum second prestress layer of the actuator  12  contacted the electrode  90  in the recess  80  substantially tangentially (nearly parallel) to the angle the actuator  12  thereby maximizing the surface area of the electrical contact between the two. 
     As shown in  FIG. 7 , in an alternate embodiment of the invention, a weight  95  may be attached to the free end  122  of the actuator  12 . The addition of the mass  95  to the free end  122  of the actuator  12 , decreases the amount of damping of the oscillation and thereby increases the duration of oscillation of the actuator  12  when it was deflected and released. By having a longer duration and higher overall amplitude oscillation, the actuator  12  is capable of developing more electrical energy from its oscillation than an actuator  12  having no additional mass at its free end  122 . 
     Referring to  FIGS. 6 and 7 : As mentioned above, it is desirable to generate an electrical signal by deforming the actuator  12 . Deformation of the actuator  12  may be accomplished by any suitable means such as manually or by mechanical deflection means such as a plunger, lever or the like. In  FIGS. 6 and 7  a simple deflector  72  is mounted to the base plate  70  in proximity to the free end  122  of the actuator  12 . This deflector assembly  72  includes a lever  86  having first and second ends  87  and  88 . The lever is pivotably mounted between the two ends  87  and  88  to a fulcrum  89 . By exerting a force on the first end  87  of the lever  86  in the direction of arrow  91 , the lever pivots about the fulcrum  89  and applies a mechanical impulse in the direction of arrow  81  to the free end  122  of the actuator  12 . Alternatively, the lever  86  may be moved opposite the direction of arrow  91  and the actuator  12  may thus be deflected in the direction opposite arrow  81 . 
     Referring now to  FIGS. 13 and 14   a - c :  FIGS. 13 and 14   a - c  show the preferred embodiment of a casing with a deflector assembly  72  and containing the actuator  12 . The base plate  70  forms the base of a casing  200 , which encloses the actuator  12 . On each side of the casing  200  is a wall  201 ,  202 ,  203  and  204  which extends perpendicularly from the top surface  70   a  of the base plate  70 . On one end of the casing  200  is mounted a deflector assembly  72 . The plunger has an interior surface  172   b  and an exterior surface  172   a , as well as a free end  173  and a mounted end  174 . More specifically, the plunger  172  is pivotably mounted on one end  174  to a wall  201  of the casing  200 . The free end  173  of the plunger  172  has a ridge  173   a  thereon which engages a lip  202   a  on the opposite wall  202  of the casing. Preferably the free end  173  of the plunger  172  is spring loaded so that the ridge  173   a  is constantly urged towards the lip  202   a . To this end, there is a preferably a spring  150  held in compression between the top surface  70   a  of the base plate  70  and the ridge  173   a  or interior surface of the plunger  172   b . This provides for device wherein an actuator  12  mounted on a base plate  70  is contained within a casing  200  formed by the base plate  70  and four walls  201 ,  202 ,  203  and  204  as well as a plunger  172  pivotably mounted opposite the base plate  70  on a wall  201  of the casing  200 . Because the plunger is pivotably mounted, placing pressure (in the direction of arrow  180  on the on the exterior surface  172   a  of the plunger  172  makes it pivot about the hinge  175  toward the top surface  70   a  of the base plate  70 . Because the plunger is pivotably mounted and spring loaded, releasing pressure from the on the exterior surface  172   a  of the plunger  172  makes it pivot about the hinge  175  away the top surface of the base plate  70  until the ridge  173   a  catches on the lip  202   a.    
     Within the casing  200  is a mounted quick release mechanism  180  comprising a spring loaded rocker arm  185  on the interior surface  172   b  of the plunger  172  which works in conjunction with a release pin  186  mounted on the top surface  70  of the base plate  70 . The quick release mechanism  180  is designed to deflect and then quickly release the free end  122  of the actuator  12  in order to allow it to vibrate between positions  291  and  292 . The quick release mechanism  180  is also designed not to interfere with the vibration of the actuator  12  as well as to return to a neutral position for follow-on deflections of the actuator  12 . 
     Referring to  FIGS. 14 a - c   : The rocker arm  185  is pivotably attached to the interior surface  172   b  of the plunger  172  above the free end  122  of the actuator  12 . More specifically, the rocker arm  185  is pivotably attached in such a way that it has a neutral position from which it may pivot away from the clamped end  121  of the actuator, but will not pivot towards the clamped end  121  of the actuator  12  from that neutral position. In other words a rotational stop  183  forms part of the quick release mechanism  180  and its placement prevents the rocker arm from pivoting beyond the neutral position at the stop  183 . The rocker arm  185  is preferably spring loaded in order to keep the rocker arm  185  in its neutral position when not being deflected. To this end a spring  187  in compression is placed on the side of the rocker arm  185  opposite the stop  183 , between the rocker arm  185  and a spring stop  188 . 
     Inside the casing  200  is also a release pin  186  which is located on the top surface  70   a  of the base plate  70 . The release pin  186  is located in a position just beyond the free end  122  of the actuator  12  in its deflected position, but not beyond the rocker arm  185 . In other words, when the plunger  172  is depressed toward the release pin  186 , depressing with it the actuator  12  from position  291  to position  292 , the release pin  186  will contact the rocker arm  185  but not the actuator  12 . As the rocker arm  185  (and actuator  12 ) are depressed further, the release pin  186  pushes the rocker arm  185  away, making the rocker arm  185  pivot away from the clamped end  121  of the actuator  12 . The rocker arm  185  pivots until the edge  122  of the actuator  12  is no longer held by the rocker arm  185  in position  292 , at which point the edge  122  of the actuator  12  is released and springs back to its undeformed state, thereby oscillating between positions  291  and  292 . 
     When pressure from the plunger  172  is released, the plunger  172  returns to its undeflected position (with the ridge  173   a  against the lip  202   a ) by virtue of the restoring force of the spring  150 . Also when the pressure from the plunger  172  is released, and the plunger  172  returns to its undeflected position, the rocker arm  185  also returns to its undeflected position (above the actuator  12  against the stop  183 ) by virtue of the restoring force of the spring  187 . Lastly, the actuator  12  also returns to its undeflected state in position  291  after its oscillations between positions  291  and  292  have ceased. 
     Referring now to  FIGS. 14 and 16   a - d :  FIGS. 14 and 16   a - d  show an alternate embodiment of a deflector assembly  72  mounted to a casing  200  that contains the actuator  12 . The base plate  70  forms the base of a casing  200 , which encloses the actuator  12 . On each side of the casing  200  is a wall  201 ,  202 ,  203  and  204  which extends perpendicularly from the top surface  70   a  of the base plate  70 . Attached to the top of the walls of the casing  200  (opposite the base plate  70 ) is a face plate  220  to which is mounted a slide mechanism  230  that acts as a deflector assembly  72 . The face plate  220  has an interior surface  220   a  and an exterior surface  220   b  and a channel  240  extending through substantially the center of the face plate  220 . The channel  240  has a first end  241  and a second end  242  and extends substantially linearly along an axis L perpendicular to the first and second walls  201  and  202  of the casing  200 . In other words, the first end  241  of the channel  240  through the face plate  220  is in proximity to the first wall  201  of the casing  200  and the second end  242  of the channel  240  through the face plate  220  is in proximity to the second wall  202  of the casing  200 . The second end of the channel  240  preferably extends further towards the second wall  202  of the casing than does the free end  122  of the actuator  12 . 
     The channel  240  is adapted to slidably retain a spring loaded paddle  250 . Preferably, the paddle has first and second ends  251  and  252  respectively and a central pin  255 . The channel in the face plate  220  allows the paddle to extend through the face plate  220 , while also slidably retaining the central pin  255  in the channel  240 . More specifically, the paddle  250  extends through the face plate  220  by means of the channel  240 , along which the paddle may be slid in a direction parallel to the channels&#39; axis L, i.e., from the clamped end  121  to the free end  122  of the actuator  12  and back. The first end  251  of the paddle  250  is located above the exterior surface  220   b  of the face plate  220  and the second end  252  of the paddle  250  is located within the casing  200  above the actuator  12 . The paddle  250  is retained in the described position be means of the pin  255  which is retained in the channel  240 . Thus, the width of the channel  240  at the exterior surface  220   b  is sufficient for the paddle upper portion  251  to pass through, as is the width of the channel  240  at the interior surface  220   a  is sufficient for the paddle lower portion  252  to pass through. The width and height of the channel  240  within the face plate  220  (between the interior and exterior surfaces  220   a  and  220   b ) is sufficient to accommodate the width and height of the central pin  255 , which is wider than the width of the paddle upper and lower portions  251  and  252 . 
     The first end  251  of the paddle  250  preferably extends a distance above the exterior surface  220   b  of the face plate  220  enough to be grasped manually. The second end  252  of the paddle  250  preferably extends into the casing  200  a distance above the actuator  12  such that the paddle  250  does not contact the clamping member  75  and/or clamped end  121  of the actuator  12 , but also far enough that it may contact and deflect the free end  122  of the actuator  12 . The paddle  250  is also preferably hinged at the second end  252  (within the casing  200  or the channel  240  at or in proximity to the central pin  255 ) in a manner that allows the second end  252  to pivot about the hinge or central pin  255  when travelling in one direction but not the other. Preferably, the second end  252  of the paddle  250  is hinged in a way that it may pivot when the paddle  250  is travelling toward the first wall  201  of the casing  200  but not pivot when travelling towards the second wall  202  of the casing  200 . 
     Preferably the paddle  250  is also spring loaded so that the paddle is constantly urged along the channel  240  towards the first wall  201  of the casing  200 . To that end, there is a spring  260  held between the paddle and the first  201  or second wall  202  of the casing  200  or most preferably the spring  260  held between the paddle  250  and the first or second end  241  or  242  of the channel  240 . In order to urge the paddle toward the first wall  201  the spring  260  is either held in tension between the paddle  250  and the first end  241  of the channel  240 , or most preferably the spring  260  is held in compression between the paddle  250  and the second end  242  of the channel  240 . 
     This provides for device wherein an actuator  12  mounted on a base plate  70  is contained within a casing  200  formed by the base plate  70 , four walls  201 ,  202 ,  203  and  204  and a face plate opposite the base plate  70 . Because the paddle  250  is slidably mounted, placing pressure (in the direction of arrow  281  on the on the  251  first end of the paddle makes it slide along the channel  240  toward the second wall  202  of the casing  200 . Because the paddle  250  is slidably mounted and spring loaded, releasing pressure from the paddle  250  makes it return along the channel  240  toward the first wall  201  of the casing  200  until it comes to rest against the first end  241  of the channel  240 . 
     Referring to  FIGS. 16 a - d   : The paddle upper portion  251  is pivotably attached to the paddle lower portion  252  below the interior surface  220   a  of the face plate  220  (within the casing  200 ) above the actuator  12 . More specifically, the paddle lower portion  252  is pivotably attached in such a way that it has a neutral position from which it may pivot away from the clamped end  121  of the actuator, but will not pivot towards the clamped end  121  of the actuator  12  from that neutral position. In other words the shape of the paddle  250  prevents the lower portion  252  from pivoting beyond the neutral position. 
     In operation, when the paddle  250  is moved (in the direction of arrow  281 ) toward the second end  242  of the channel  240 , the paddle lower portion  252  contacts concave face  12   c  of the actuator  12  and commences to deflect the actuator free end  122  (away from position  291 ). As the paddle  250  continues to move in the direction of arrow  281 , the paddle lower portion  252  depresses the free end  122  of the actuator  12  to its maximum deflection at position  292  when the free end  122  is directly beneath the paddle lower portion  252 . When the paddle moves further from this point in the direction of arrow  281 , the free end  122  of the actuator  12  is abruptly released from the applied deflection of the paddle lower portion  252 . Upon release, the edge  122  of the actuator  12  springs back to its undeformed state at position  291 , thereby oscillating between positions  291  and  292 . Upon release of pressure (in the direction of arrow  281 ) from the paddle  250 , the paddle then travels in the direction of arrow  282 , by virtue of the restoring force of the spring  260 . As the paddle  250  returns towards its undeflected position (towards the first end  241  of the channel  240 ), the free end  122  of the actuator  12  in position  291  applies pressure against the lower portion  252  of the paddle  250 . In response to the pressure being applied to the paddle lower portion opposite the direction of travel of the upper portion  251 , the lower portion  252  pivots about the hinged central pin  255  of the paddle. After the paddle lower portion  252  has traveled in the direction of arrow  282  beyond the free end  122  of the actuator, the lower portion  252  returns to its undeflected (unbent) state. The pivoting of the paddle lower portion  252  allows the paddle  250  to return to its neutral undeflected position at the first end  241  of the channel  240 . 
     When the end  122  of the actuator  12  is deflected and then released (either manually or using a deflector assembly  72  such as in  FIG. 6, 7 , or  13 - 16 ), the end  122  of the actuator  12 , much like a diving board, oscillates back and forth between positions  291  and  292 . This is because the substrate and prestress layer  64  and  68  to which the ceramic  67  is bonded exert a compressive force on the ceramic  67  thereby providing a restoring force. Therefore, the actuator  12  has a coefficient of elasticity or spring constant that causes the actuator  12  to return to its undeformed neutral state at position  291 . The oscillation of the actuator  12  has the waveform of a damped harmonic oscillation, as is illustrated in  FIG. 10 a   . In other words, the amplitude of the oscillation of the free end  122  of the actuator  12  is at its maximum immediately following (within a few oscillations after) the release of the mechanical impulse from the free end  122  of the actuator  12 . As the actuator  12  continues to vibrate, the amplitude gradually decreases over time (approximately exponentially) until the actuator  12  is at rest in its neutral position. 
     The applied force, whether by manual or other mechanical deflection means  72  causes the piezoelectric actuator  12  to deform and by virtue of the piezoelectric effect, the deformation of the piezoelectric element  67  generates an instantaneous voltage between the faces  12   a  and  12   c  of the actuator  12 , which produces an electrical signal. Furthermore, when the force is removed from the piezoelectric actuator  12 , the actuator oscillates between positions  291  and  292  until it gradually returns to its original shape. As the actuator  12  oscillates, the ceramic layer  67  strains, becoming alternately more compressed and less compressed. The polarity of the voltage produced by the ceramic layer  67  depends on the direction of the strain, and therefore, the polarity of the voltage generated in compression is opposite to the polarity of the voltage generated in tension. Therefore, as the actuator  12  oscillates, the voltage produced by the ceramic element  67  oscillates between a positive and negative voltage for a duration of time. The duration of the oscillation, and therefore the duration of the oscillating electrical signal produced, is preferably in the range of 100 250 milliseconds, depending on the shape, mounting and amount of force applied to the actuator  12 . 
     The electrical signal generated by the actuator  12  is applied to downstream circuit elements via wires  14  connected to the actuator  12 . More specifically, a first wire  14  is connected to the electrode  90  which extends into the recess  80  and contacts the electrode  68  on the convex face  12   a  of the actuator  12 . Preferably the wire  14  is connected to the electrode  90  outside of the recess close to the end of the base plate  70  opposite the end having the clamping member  75 . A second wire  14  is connected directly to the first prestress layer  64 , i.e., the substrate  64  which acts as an electrode on the concave face  12   c  of the actuator  12 . 
     Referring to  FIG. 8 , the actuator  12  is connected to circuit components downstream in order to generate an RF signal for actuation of a switch initiator. These circuit components include a rectifier  31 , a voltage regulator U 2 , an encoder  40  (preferably comprising a peripheral interface controller (PIC) chip) as well as an RF generator  50  and antenna  60 .  FIG. 10 b    shows the waveform of the electrical signal of  FIG. 10 a    after it has been rectified.  FIG. 10 c    shows the waveform of the rectified electrical signal of  FIG. 10 b    after it has been regulated to a substantially uniform voltage, preferably 3.3 VDC. 
     Referring now to  FIG. 9 : The actuator  12  is first connected to a rectifier  31 . Preferably the rectifier  31  comprises a bridge rectifier  31  comprising four diodes D 1 , D 2 , D 3  and D 4  arranged to only allow positive voltages to pass. The first two diodes D 1  and D 2  are connected in series, i.e., the anode of D 1  connected to the cathode of D 2 . The second two diodes D 3  and D 4  are connected in series, i.e., the anode of D 3  connected to the cathode of D 4 . The anodes of diodes D 2  and D 4  are connected, and the cathodes of diodes D 1  and D 3  are connected, thereby forming a bridge rectifier. The rectifier is positively biased toward the D 2  D 4  junction and negatively biased toward the D 1  D 3  junction. One of the wires  14  of the actuator  12  is electrically connected between the junction of diodes D 1  and D 2 , whereas the other wire  14  (connected to the opposite face of the actuator  12 ) is connected to the junction of diodes D 3  and D 4 . The junction of diodes D 1  and D 3  are connected to ground. A capacitor C 11  is preferably connected on one side to the D 2  D 4  junction and on the other side of the capacitor C 11  to the D 1  D 3  junction in order to isolate the voltages at each side of the rectifier from each other. Therefore, any negative voltages applied to the D 1  D 2  junction or the D 3  D 4  junction will pass through diodes D 1  or D 3  respectively to ground. Positive voltages applied to the D 1  D 2  junction or the D 3  D 4  junction will pass through diodes D 2  or D 4  respectively to the D 2  D 4  junction. The rectified waveform is shown in  FIG. 10   b.    
     The circuit also comprises a voltage regulator U 2 , which controls magnitude of the input electrical signal downstream of the rectifier  31 . The rectifier  31  is electrically connected to a voltage regulator U 2  with the D 2  D 4  junction connected to the Vin pin of the voltage regulator U 2  and with the D 1  D 3  junction connected to ground and the ground pin of the voltage regulator U 2 . The voltage regulator U 2  comprises for example a LT1121 chip voltage regulator U 2  with a 3.3 volts DC output. The output voltage waveform is shown in  FIG. 10 c    and comprises a substantially uniform voltage signal of 3.3 volts having a duration of approximately 100 250 milliseconds, depending on the load applied to the actuator  12 . The regulated waveform is shown in  FIG. 10 b   . The output voltage signal from the voltage regulator (at the Vout pin) may then be transmitted via another conductor to the relay switch  290 , in order to change the position of a relay switch  290  from one position to another. Preferably however, the output voltage is connected through an encoder  40  to an RF generation section  50  of the circuit. 
     Referring again to  FIGS. 8 and 9 : The output of the voltage regulator U 2  is preferably used to power an encoder  40  or tone generator comprising a peripheral interface controller (PIC) microcontroller that generates a pulsed tone. This pulsed tone modulates an RF generator section  50  which radiates an RF signal using a tuned loop antenna  60 . The signal radiated by the loop antenna is intercepted by an RF receiver  270  and a decoder  280  which generates a relay pulse to activate the relay  290 . 
     The output of the voltage regulator U 2  is connected to a PIC microcontroller, which acts as an encoder  40  for the electrical output signal of the regulator U 2 . More specifically, the output conductor for the output voltage signal (nominally 3.3 volts) is connected to the input pin of the programmable encoder  40 . Types of register-based PIC microcontrollers include the eight-pin PIC12C5XX and PIC12C67x, baseline PIC16C5X, midrange PIC16CXX and the high-end PIC17CXX/PIC18CXX. These controllers employ a modified Harvard, RISC architecture that support various-width instruction words. The datapaths are 8 bits wide, and the instruction widths are 12 bits wide for the PIC16C5X/PIC12C5XX, 14 bits wide for the PIC12C67X/PIC16CXX, and 16 bits wide for the PIC17CXX/PIC18CXX. PICMICROS are available with one-time programmable EPROM, flash and mask ROM. The PIC17CXX/PIC18CXX support external memory. The encoder  40  comprises for example a PIC model 12C671. The PIC12C6XX products feature a 14-bit instruction set, small package footprints, low operating voltage of 2.5 volts, interrupts handling, internal oscillator, on-board EEPROM data memory and a deeper stack. The PIC12C671 is a CMOS microcontroller programmable with 35 single word instructions and contains 1024.times.14 words of program memory, and 128 bytes of user RAM with 10 MHz maximum speed. The PIC12C671 features an 8-level deep hardware stack, 2 digital timers (8-bit TMRO and a Watchdog timer), and a four-channel, 8-bit A/D converter. 
     The output of the PIC may include square, sine or saw waves or any of a variety of other programmable waveforms. Typically, the output of the encoder  40  is a series of binary square waveforms (pulses) oscillating between 0 and a positive voltage, preferably +3.3 VDC. The duration of each pulse (pulse width) is determined by the programming of the encoder  40  and the duration of the complete waveform is determined by the duration of output voltage pulse of the voltage regulator U 2 . A capacitor C 5  is preferably be connected on one end to the output of the voltage regulator U 2 , and on the other end to ground to act as a filter between the voltage regulator U 2  and the encoder  40 . 
     Thus, the use of an IC as a tone generator or encoder  40  allows the encoder  40  to be programmed with a variety of values. The encoder  40  is capable of generating one of many unique encoded signals by simply varying the programming for the output of the encoder  40 . More specifically, the encoder  40  can generate one of a billion or more possible codes. It is also possible and desirable to have more than one encoder  40  included in the circuit in order to generate more than one code from one actuator or transmitter. Alternately, any combination of multiple actuators and multiple pulse modification subcircuits may be used together to generate a variety of unique encoded signals. Alternately the encoder  40  may comprise one or more inverters forming a series circuit with a resistor and capacitor, the output of which is a square wave having a frequency determined by the RC constant of the encoder  40 . 
     The DC output of the voltage regulator U 2  and the coded output of the encoder  40  are connected to an RF generator  50 . A capacitor C 6  may preferably be connected on one end to the output of the encoder  40 , and on the other end to ground to act as a filter between the encoder  40  and the RF generator  50 . The RF generator  50  consists of tank circuit connected to the encoder  40  and voltage regulator U 2  through both a bipolar junction transistor (BJT) Q 1  and an RF choke. More specifically, the tank circuit consists of a resonant circuit comprising an inductor L 2  and a capacitor C 8  connected to each other at each of their respective ends (in parallel). Either the capacitor C 8  or the inductor L 2  or both may be tunable in order to adjust the frequency of the tank circuit. An inductor L 1  acts as an RF choke, with one end of the inductor L 1  connected to the output of the voltage regulator U 2  and the opposite end of the inductor L 1  connected to a first junction of the L 2  C 8  tank circuit. Preferably, the RF choke inductor L 1  is an inductor with a diameter of approximately 0.125 inches and turns on the order of thirty and is connected on a loop of the tank circuit inductor L 2 . The second and opposite junction of the L 2  C 8  tank circuit is connected to the collector of BJT Q 1 . The base of the BJT Q 1  is also connected through resistor R 2  to the output side of the encoder  40 . A capacitor C 7  is connected to the base of a BJT Q 1  and to the first junction of the tank circuit. Another capacitor C 9  is connected in parallel with the collector and emitter of the BJT Q 1 . This capacitor C 9  improves the feedback characteristics of the tank circuit. The emitter of the BJT Q 1  is connected through a resistor R 3  to ground. The emitter of the BJT Q 1  is also connected to ground through capacitor C 10  which is in parallel with the resistor R 3 . The capacitor C 10  in parallel with the resistor R 4  provides a more stable conduction path from the emitter at high frequencies. 
     Referring now to  FIGS. 11 and 12 : The RF generator  50  works in conjunction with a tuned loop antenna  60 . In the preferred embodiment, the inductor L 2  of the tank circuit serves as the loop antenna  60 . More preferably, the inductor/loop antenna L 2  comprises a single rectangular loop of copper wire having an additional smaller loop or jumper  61  connected to the rectangular loop L 2 . Adjustment of the shape and angle of the smaller loop  61  relative to the rectangular loop L 2  is used to increase or decrease the apparent diameter of the inductor L 2  and thus tunes the RF transmission frequency of the RF generator  50 . In an alternate embodiment, a separate tuned antenna may be connected to the second junction of the tank circuit. 
     In operation: The positive voltage output from the voltage regulator U 2  is connected the encoder  40  and the RF choke inductor L 1 . The voltage drives the encoder  40  to generate a coded square wave output, which is connected to the base of the BJT Q 1  through resistor R 2 . When the coded square wave voltage is zero, the base of the BJT Q 1  remains de-energized, and current does not flow through the inductor L 1 . When the coded square wave voltage is positive, the base of the BJT Q 1  is energized through resistor R 2 . With the base of the BJT Q 1  energized, current is allowed to flow across the base from the collector to the emitter and current is also allowed to flow across the inductor L 1 . When the square wave returns to a zero voltage, the base of the BJT Q 1  is again de-energized. 
     When current flows across the choke inductor L 1 , the tank circuit capacitor C 8  charges. Once the tank circuit capacitor C 8  is charged, the tank circuit begins to resonate at the frequency determined by the circuit&#39;s LC constant. For example, a tank circuit having a 7 picofarad capacitor and an inductor L 2  having a single rectangular loop measuring 0.7 inch by 0.3 inch, the resonant frequency of the tank circuit is 310 MHz. The choke inductor L 1  prevents RF leakage into upstream components of the circuit (the PIC) because changing the magnetic field of the choke inductor L 1  produces an electric field opposing upstream current flow from the tank circuit. To produce an RF signal, charges have to oscillate with frequencies in the RF range. Thus, the charges oscillating in the tank circuit inductor/tuned loop antenna L 2  produce an RF signal of preferably 310 MHz. As the square wave output of the inverter turns the BJT Q 1  on and off, the signal generated from the loop antenna  60  comprises a pulsed RF signal having a duration of 100 250 milliseconds and a pulse width determined by the encoder  40 , (typically of the order of 0.1 to 5.0 milliseconds thus producing 20 to 2500 pulses at an RF frequency of approximately 310 MHz. The RF generator section  50  is tunable to multiple frequencies. Therefore, not only is the transmitter capable of a great number of unique codes, it is also capable of generating each of these codes at a different frequency, which greatly increases the number of possible combinations of unique frequency-code signals. 
     The RF generator  50  and antenna  60  work in conjunction with an RF receiver  270 . More specifically, an RF receiver  270  in proximity to the RF transmitter  60  (within 300 feet) can receive the pulsed RF signal transmitted by the RF generator  50 . The RF receiver  270  comprises a receiving antenna  270  for intercepting the pulsed RF signal (tone). The tone generates a pulsed electrical signal in the receiving antenna  270  that is input to a microprocessor chip that acts as a decoder  280 . The decoder  280  filters out all signals except for the RF signal it is programmed to receive, e.g., the signal generated by the RF generator  50 . An external power source is also connected to the microprocessor chip/decoder  280 . In response to the intercepted tone from the RF generator  50 , the decoder chip produces a pulsed electrical signal. The external power source connected to the decoder  280  augments the pulsed voltage output signal developed by the chip. This augmented (e.g., 120 VAC) voltage pulse is then applied to a conventional relay  290  for changing the position of a switch within the relay. Changing the relay switch position is then used to turn an electrical device with a bipolar switch on or off, or toggle between the several positions of a multiple position switch. Zero voltage switching elements may be added to ensure the relay  290  activates only once for each depression and recovery cycle of the flextensional transducer element  12 . 
     Switch Initiator System with Trainable Receiver 
     Several different RF transmitters may be used that generate different tones for controlling relays that are tuned to receive that tone. In another embodiment, digitized RF signals may be coded and programmable (as with a garage door opener) to only activate a relay that is coded with that digitized RF signal. In other words, the RF transmitter is capable of generating at least one tone, but is preferably capable of generating multiple tones. Most preferably, each transmitter is programmed with one or more unique coded signals. This is easily done, since programmable ICs for generating the tone can have over 2 30  possible unique signal codes which is the equivalent of over 1 billion codes. Most preferably the invention comprises a system of multiple transmitters and one or more receivers for actuating building lights, appliances, security systems and the like. In this system for remote control of these devices, an extremely large number of codes are available for the transmitters for operating the lights, appliances and/or systems and each transmitter has at least one unique, permanent and nonuser changeable code. The receiver and controller module at the lights, appliances and/or systems is capable of storing and remembering a number of different codes corresponding to different transmitters such that the controller can be programmed so as to actuated by more than one transmitted code, thus allowing two or more transmitters to actuate the same light, appliance and/or system. 
     The remote control system includes a receiver/controller for learning a unique code of a remote transmitter to cause the performance of a function associated with the system, light or appliance with which the receiver/controller module is associated. The remote control system is advantageously used, in one embodiment, for interior or exterior lighting, household appliances or security system. Preferably, a plurality of transmitters is provided wherein each transmitter has at least one unique and permanent non-user changeable code and wherein the receiver can be placed into a program mode wherein it will receive and store two or more codes corresponding to two or more different transmitters. The number of codes which can be stored in transmitters can be extremely high as, for example, greater than one billion codes. The receiver has a decoder module therein which is capable of learning many different transmitted codes, which eliminates code switches in the receiver and also provides for multiple transmitters for actuating the light or appliance. Thus, the invention makes it possible to eliminate the requirements for code selection switches in the transmitters and receivers. 
     Referring to  FIG. 8 : The receiver module  101  includes a suitable antenna  270  for receiving radio frequency transmissions from one or more transmitters  126  and  128  and supplies an input to a decoder  280  which provides an output to a microprocessor unit  244 . The microprocessor unit  244  is connected to a relay device  290  or controller which switches the light or appliance between one of two or more operation modes, i.e., on, off, dim, or some other mode of operation. A switch  222  is mounted on a switch unit  219  connected to the receiver and also to the microprocessor  244 . The switch  222  is a two position switch that can be moved between the “operate” and “program” positions to establish operate and program modes. 
     In the invention, each transmitter, such as transmitters  126  and  128 , has at least one unique code which is determined by the tone generator/encoder  40  contained in the transmitter. The receiver unit  101  is able to memorize and store a number of different transmitter codes which eliminates the need of coding switches in either the transmitter or receiver which are used in the prior art. This also eliminates the requirement that the user match the transmitter and receiver code switches. Preferably, the receiver  101  is capable of receiving many transmitted codes, up to the available amount of memory locations  147  in the microprocessor  144 , for example one hundred or more codes. 
     When the controller  290  for the light or appliance is initially installed, the switch  222  is moved to the program mode and the first transmitter  126  is energized so that the unique code of the transmitter  126  is transmitted. This is received by the receiver module  101  having an antenna  270  and decoded by the decoder  280  and supplied to the microprocessor unit  244 . The code of the transmitter  126  is then supplied to the memory address storage  247  and stored therein. Then if the switch  222  is moved to the operate mode and the transmitter  126  energized, the receiver  270 , decoder  280  and the microprocessor  244  will compare the received code with the code of the transmitter  126  stored in the first memory location in the memory address storage  247  and since the stored memory address for the transmitter  126  coincides with the transmitted code of the transmitter  126  the microprocessor  244  will energize the controller mechanism  290  for the light or appliance to energize de-energize or otherwise operate the device. 
     In order to store the code of the second transmitter  128  the switch  222  is moved again to the program mode and the transmitter  128  is energized. This causes the receiver  270  and decoder  280  to decode the transmitted signal and supply it to the microprocessor  244  which then supplies the coded signal of the transmitter  128  to the memory address storage  247  where it is stored in a second address storage location. Then the switch  222  is moved to the operate position and when either of the transmitters  126  and  128  are energized, the receiver  270  decoder  280  and microprocessor  244  will energize the controller mechanism  290  for the light or appliance to energize de-energize or otherwise operate the device. Alternately, the signal from the first transmitter  126  and second transmitter  128  may cause separate and distinct actions to be performed by the controller mechanism  290 . 
     Thus, the codes of the transmitters  126  and  128  are transmitted and stored in the memory address storage  247  during the program mode after which the system, light or appliance controller  290  will respond to either or both of the transmitters  126  and  128 . Any desired number of transmitters can be programmed to operate the system, light or appliance up to the available memory locations in the memory address storage  247 . 
     This invention eliminates the requirement that binary switches be set in the transmitter or receiver as is done in systems of the prior art. The invention also allows a controller to respond to a number of different transmitters because the specific codes of a number of the transmitters are stored and retained in the memory address storage  247  of the receiver module  101 . 
     In yet another more specific embodiment of the invention, each transmitter  126  or  128  contains two or more unique codes for controlling a system, light or appliance. One code corresponds in the microprocessor to the “on” position and another code corresponds in the microprocessor  244  to the “off” position of the controller  290 . Alternately, the codes may correspond to “more” or “less” respectively in order to raise or lower the volume of a sound device or to dim or undim lighting for example. Lastly, the unique codes in a transmitter  126  or  128  may comprise four codes which the microprocessor interprets as “on”, “off”, “more” and “less” positions of the controller  290 , depending on the desired setup of the switches. Alternatively, a transmitter  126  or  128  may only have two codes, but the microprocessor  244  interprets repeated pushes of “on” or “off” signals respectively to be interpreted as dim up and dim down respectively. 
     In another embodiment of the invention, receiver modules  101  may be trained to accept the transmitter code(s) in one-step. Basically, the memory  247  in the microprocessor  244  of the receiver modules  101  will have “slots” where codes can be stored. For instance one slot may be for all of the codes that the memory  247  accepts to be turned on, another slot for all the off codes, another all the 30% dimmed codes, etc. 
     Each transmitter  126  has a certain set of codes. For example one transmitter may have just one code, a “toggle” code, wherein the receiver module  101  knows only to reverse its current state, if it&#39;s on, turn off, and if it&#39;s off, turn on. Alternatively, a transmitter  126  may have many codes for the complex control of appliances. Each of these codes is “unique”. The transmitter  126  sends out its code set in a way in which the receiver  101  knows in which slots to put each code. Also, with the increased and longer electrical signal that can be generated in the transmitter  126 , a single transmission of a code set is achievable even with mechanically produced voltage. As a back-up, if this is not true, and if wireless transmission uses up more electricity than we have available, some sort of temporary wired connection (jumper not shown) between each transmitter and receiver target is possible. Although the disclosed embodiment shows manual or mechanical interaction with the transmitter and receiver to train the receiver, it is yet desirable to put the receiver in reprogram mode with a wireless transmission, for example a “training” code. 
     In yet another embodiment of the invention, the transmitter  126  may have multiple unique codes and the transmitter randomly selects one of the multitude of possible codes, all of which are programmed into the memory allocation spaces  247  of the microprocessor  244 . 
     In yet another embodiment of the invention, the transmitter  126  signal need not be manually operated or triggered, but may as easily be operated by any manner of mechanical force, i.e., the movement of a window, door, safe, foot sensor, etc. and that a burglar alarm sensor might simultaneously send a signal to the security system and a light in the intruded upon room. Likewise, the transmitter  126  may be combined with other apparatus. For example, a transmitter  126  may be located within a garage door opener which can also turn on one or more lights in the house, when the garage door opens. 
     Furthermore, the transmitters can talk to a central system or repeater which re-transmits the signals by wire or wireless means to lights and appliances. In this manner, one can have one transmitter/receiver set, or many transmitters interacting with many different receivers, some transmitters talking to one or more receivers and some receivers being controlled by one or more transmitters, thus providing a broad system of interacting systems and wireless transmitters. Also, the transmitters and receivers may have the capacity of interfacing with wired communications like SMARTHOME or BLUETOOTH. 
     While in the preferred embodiment of the invention, the actuation means has been described as from mechanical to electric, it is within the scope of the invention to include batteries in the transmitter to power or supplement the power of the transmitter. For example, rechargeable batteries may be included in the transmitter circuitry and may be recharged through the electromechanical actuators. These rechargeable batteries may thus provide backup power to the transmitter. 
     It is seen that the present invention allows a receiving system to respond to one of a plurality of transmitters which have different unique codes which can be stored in the receiver during a program mode. Each time the “program mode switch”  222  is moved to the program position, a different storage can be connected so that the new transmitter code would be stored in that address. After all of the address storage capacity have been used additional codes would erase all old codes in the memory address storage before storing a new one. 
     This invention is safe because it eliminates the need for 120 VAC (220 VAC in Europe) lines to be run to each switch in the house. Instead the higher voltage overhead AC lines are only run to the appliances or lights, and they are actuated through the self-powered switching device and relay switch. The invention also saves on initial and renovation construction costs associated with cutting holes and running the electrical lines to/through each switch and within the walls. The invention is particularly useful in historic structures undergoing preservation, as the walls of the structure need not be destroyed and then rebuilt. The invention is also useful in concrete construction, such as structures using concrete slab and/or stucco construction and eliminate the need to have wiring on the surface of the walls and floors of these structures. 
     While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one preferred embodiment thereof. Many other variations are possible, for example: 
     In addition to piezoelectric devices, the electroactive elements may comprise magnetostrictive or ferroelectric devices; 
     Rather than being arcuate in shape, the actuators may normally be flat and still be deformable; 
     Multiple high deformation piezoelectric actuators may be placed, stacked and/or bonded on top of each other; 
     Multiple piezoelectric actuators may be placed adjacent each other to form an array. 
     Larger or different shapes of THUNDER elements may also be used to generate higher impulses. 
     The piezoelectric elements may be flextensional actuators or direct mode piezoelectric actuators. 
     A bearing material may be disposed between the actuators and the recesses or switch plate in order to reduce friction and wearing of one element against the next or against the frame member of the switch plate. 
     Other means for applying pressure to the actuator may be used including simple application of manual pressure, rollers, pressure plates, toggles, hinges, knobs, sliders, twisting mechanisms, release latches, spring loaded devices, foot pedals, game consoles, traffic activation and seat activated devices.