초록 ▼

A method and system employing a feedback signal indicative of monitored motion of an electro-mechanical acoustic transducer to generate one or both of a control signal for driving the transducer at its natural resonance frequency, and a warning signal indicating that the transducer is not vibrating

A method and system employing a feedback signal indicative of monitored motion of an electro-mechanical acoustic transducer to generate one or both of a control signal for driving the transducer at its natural resonance frequency, and a warning signal indicating that the transducer is not vibrating at a frequency within a selected frequency range. In preferred embodiments, the transducer is a voice coil loudspeaker mounted in or on a vehicle. In other preferred embodiments, the electro-mechanical transducer is driven by an initial electrical pulse followed by a sequence of electrical pulses. A feedback signal indicative of monitored motion of a moving portion of the transducer is generated. Each pulse (following the initial pulse) is applied at a time (determined by the feedback signal) so as to drive the transducer at its actual natural resonance frequency. Some embodiments monitor the peak velocity (rather than displacement) of a driven electro-mechanical transducer, process the monitored peak velocity signal to generate feedback indicative of actual radiated energy from the transducer, and generate from the feedback signal one or both of a control signal for driving the transducer in a desired manner and a warning signal indicating that the transducer has not radiated a selected minimum amount of energy.

대표청구항 ▼

An acoustic transducer system, including: an electro-mechanical acoustic transducer, having a movable portion, wherein the transducer is a voice coil loudspeaker, and the movable portion of the transducer includes a voice coil; driving means for driving the transducer at any selected frequency withi

An acoustic transducer system, including: an electro-mechanical acoustic transducer, having a movable portion, wherein the transducer is a voice coil loudspeaker, and the movable portion of the transducer includes a voice coil; driving means for driving the transducer at any selected frequency within a range of frequencies including a nominal natural resonance frequency of said transducer; detector means, coupled to the transducer, for generating a feedback signal indicative of actual natural resonance frequency of the movable portion of the transducer; and control means for receiving the feedback signal, and controlling the driving means in response to the feedback signal to cause said driving means to drive the transducer at said actual natural resonance frequency, wherein the driving means includes means for applying a sequence of voltage pulses across the transducer, wherein the detector means is a high-impedance detector circuit connected across the voice coil, and wherein the feedback signal is indicative of a zero crossing of voltage across the voice coil following application of each of said pulses.