Abstract: The invention is an modified audible signal, such as a piezoelectric noise-making and audible signaling device, which further includes a hydrophobic covering material, such as polytetrafluoroethylene (PTFE). The hydrophobic covering material is known to be water resistant, but does not effect the sound of the audible signaling device, thereby delaying or preventing the failure of the audible signaling device from water corrosion.

Abstract: A multi-function electronic warning horn system comprises a couple of horns (1, 2) and a microprocessor (6), integrated in an electronic module (16) comprising a voltage adjuster (13), an oscillator (17), power stages (3, 4) and a control circuit (7). Horns (1, 2) are controlled by either the push-button (5) of the steering wheel for the traditional function of acoustic signaling or by a coded signal transmitted to microprocessor (6) by the “intelligent” electronic unit or onboard computer of the vehicle for the function of buzzer.

Abstract: In a signal generation circuit for a compound acoustic actuator that generates a sound and a vibration in response to a frequency of a signal input to the compound acoustic actuator, the signal generation circuit comprising a plurality of signal data stored in a memory to generate a plurality of signals having mutually different frequencies, the plurality of signals at least including a signal, a frequency of which is equal to a resonant frequency causing the compound acoustic actuator to generate the vibration, a synthesizing means to synthesize a plurality of drive signals in accordance with the plurality of signal data so as to cause the compound acoustic actuator to generate the vibration, and a sweeping means to sweep the plurality of drive signals, repeatedly.

Abstract: A piezoelectric transducer driving circuit has a main oscillator stage, a buffer circuit, and a voltage-doubling circuit. The main oscillator stage includes a frequency-swept signal generator that can be configured to provide different outputs to the buffers, which in turn provide the output to the voltage-doubling circuit, which supplies the piezoelectric transducer, causing it to mechanically deform and produce audible sounds of different types.

Abstract: In a signal generation circuit for a compound acoustic actuator that generates a sound and a vibration in response to a frequency of a signal input to the compound acoustic actuator, the signal generation circuit comprising a plurality of signal data stored in a memory to generate a plurality of signals having mutually different frequencies, the plurality of signals at least including a signal, a frequency of which is equal to a resonant frequency causing the compound acoustic actuator to generate the vibration, a synthesizing means to synthesize a plurality of drive signals in accordance with the plurality of signal data so as to cause the compound acoustic actuator to generate the vibration, and a sweeping means to sweep the plurality of drive signals, repeatedly.

Abstract: A sounder device includes a piezoelectric resonant transducer, an amplifier and a coupling transformer to drive the transducer, an electronic signal produced to provide an input signal to the amplifier, and in which the electronic signal producer includes at least two lower frequency oscillators, a logical “OR” circuit having inputs from each of the lower frequency pulse oscillators, a resonant frequency pulse oscillator having a higher frequency near the resonant frequency of the transducer, a logical “AND” circuit having a first input connected to the output of the logical “OR” circuit, a second input connected to the output of the resonant frequency oscillator, and having an output connected to the amplifier input.

Abstract: The invention is an improved piezoelectric noise-making and audible signaling device which produces a distinctive 2 KHz tone that is more pronounced and significantly easier to perceive, especially in a noisy environment. The volume of the audible tone is amplified by using two or three sound-amplifying chambers or cavities.

Abstract: A sounder device includes a piezoelectric resonant transducer, an amplifier and a coupling transformer to drive the transducer, an electronic signal produced to provide an input signal to the amplifier, and in which the electronic signal producer includes at least two lower frequency oscillators, a logical “OR” circuit having inputs from each of the lower frequency pulse oscillators, a resonant frequency pulse oscillator having a higher frequency near the resonant frequency of the transducer, a logical “AND” circuit having a first input connected to the output of the logical “OR” circuit, a second input connected to the output of the resonant frequency oscillator, and having an output connected to the amplifier input.

Abstract: A piezoelectric transducer driving circuit has a main oscillator stage, a buffer circuit, and a voltage-doubling circuit. The main oscillator stage includes a frequency-swept signal generator that can be configured to provide different outputs to the buffers, which in turn provide the output to the voltage-doubling circuit, which supplies the piezoelectric transducer, causing it to mechanically deform and produce audible sounds of different types.

Abstract: A personal communication device comprises a housing, a receiver component, a processor and a multi-functional piezoelectric transducer. The transducer is mounted within the housing, is electrically connected to the processor, and produces mechanical vibrations in response to the electrical signals transmitted by the processor. These mechanical vibrations are over a broad range of frequencies and are of a force sufficient to generate a tactile alert, an audible alert, and audible sound over the audible frequency range.

Abstract: A novel modular audible signaling device is provided capable of expanded functionality, such as the provision of visual signaling as well. A piezoelectric transducer audible alarm signaling device is provided with an assembly having a housing defining an interior holding a piezoelectric transducer, the housing having a first exterior portion for attachment to a surface and a second exterior portion extending beyond the surface, wherein the first exterior portion and the second exterior portion comprise at least one pair of communicating apertures whereby an electrical conductor may extend through the at least one pair of apertures to the surface.

Abstract: A novel modular audible signaling device is provided capable of expanded functionality, such as the provision of visual signaling as well. A piezoelectric transducer audible alarm signaling device is provided with an assembly having a housing defining an interior holding a piezoelectric transducer, the housing having a first exterior portion for attachment to a surface and a second exterior portion extending beyond the surface, wherein the first exterior portion and the second exterior portion comprise at least one pair of communicating apertures whereby an electrical conductor may extend through the at least one pair of apertures to the surface.

Abstract: A circuit for automatically driving a mechanical device at its resonance frequency is provided. To do so, the circuit detects non-resonance driving conditions of the mechanical device being coupled to and driven by such circuit. Based on such detection, the circuit generates a signal to drive the device at its resonance frequency.

Abstract: A microcontroller is used to drive a piezoelectric transducer. Certain pins on the microcontroller are indicative of selection signals. The selector can be activated either by a user directly (e.g., by pushing buttons), by an offboard actuator (e.g., another microcontroller), or by any method known in the art for activating switches. In one embodiment, an output pin of the microcontroller acts as output for a high-low oscillator. The oscillation amplitude toggles between 0 and 5 volts in a square wave fashion. The output pin is coupled to the base of a bipolar junction transistor so that the transistor turns on and off as a switch in response to the high-low oscillations.

Abstract: An electromagnetic sound generator has a vibrating plate mounted in a case. An armature is secured on the vibrating plate at a central portion thereof. The armature has a concave spherical shape.

Abstract: A piezoelectric buzzer formed by using a piezoelectric ceramic having both a higher heat resistance and a higher piezoelectric characteristics than those of a conventional product. The piezoelectric buzzer 10 of the present invention has a metal plate 12. Formed on the metal plate 12 is a piezoelectric ceramic 14. Further, formed on the piezoelectric ceramic 14 is an electrode 16. The piezoelectric composition forming the piezoelectric ceramic is a piezoelectric ceramic composition characterized in that about 0.2 to 2 mol % of the Pb atoms of a lead zirconate titanate (PZT) represented by the composition formula PbA[(TixZr1-x)a(SnyCr1-y)bSbc]O3 has been displaced by La, wherein 0.94≦A≦1.02, 0.46≦x≦0.51, 0.01≦y≦0.5, 0.01≦b≦0.03, 0.01≦c≦0.04,a+b+c=1.

Abstract: Device for identifying multiple two-conductor alarm wires originating from a common location but terminating at individual remote locations. This device is utilized at the common location by connecting a plurality of test leads and common leads to wires to be identified. User then visits the remote locations where alarm wires connected to test leads and common leads are suspected to terminate. Device emits frequency pulses along connected wires. Using an inductance amplifier probe user can locate and verify that the wire at the remote location is indeed connected to the device. If necessary the user can find the wire it buried within the wall and when found, strip back insulation of the same terminating end of alarm wire and momentarily join the two conductors together. The result is a number of audible beeps sounding from a piezoelectric transducer from the device letting user, who is at the remote location, know which test lead is connected to the wires that were momentarily joined together.

Abstract: A horn switch assembly (26) is mounted on inner surface (28) of airbag cover (16). Horn switch assembly (26) includes a sensor (30) coupled to cover (16), and a load and rate sensing device (32) arranged to interact with sensor (30) and with a vehicle horn. Deflection of outer surface (18) of airbag cover (16) applies a force to sensor (30). Deflection of outer surface (18) of airbag cover (16) may be caused by an operator action of pressing on airbag cover (16). In which case, the increase in the magnitude of the force on sensor (30) will be rapid, and load and rate sensing device (32) will cause the vehicle horn to sound. Alternatively, deflection of outer surface (18) of airbag cover (16) may be caused by shrinkage of airbag cover (16) due to an ambient temperature drop. In which case, the increase in the magnitude of the force on sensor (30) will be slow, and load and rate sensing device (32) will not cause the horn to sound.

Abstract: A portable alarm device of minimum dimensions and weight having secure activation and deactivation, and a visible alarm display, is activated by a motion detection switch, which, when displaced from it's original position, causes electrical current from an internal power source to activate a high decibel alarm speaker. The alarm device can be permanently attached to the object to be secured or attached by an easily removeable fastener system so that the alarm can be used on various objects as a security need may arise.