Matches 1 - 50 out of 51 1 2 >


Match Document Document Title
8144887 Electronic stethoscope and the stethoscope auscultation method using the same  
The present invention relates to a stethoscope auscultation method, adapted for an improved stethoscope so as to be used for assisting a medical diagnosis according to visceral sounds. The...
8121303 Stethoscope capable of eliminating unwanted sounds and method thereof  
A stethoscope capable of eliminating unwanted sounds and method thereof, the stethoscope and method thereof mainly use a stethoscope head containing a sensor and a signal processing circuit. By way...
8121844 Dimension measurement system  
A dimension measurement system is provided. The dimension measurement system includes a speech I/O device fit in an ear canal of a worker, generating a voice signal from vibration in the air...
8073149 Loudspeaker device  
The loudspeaker device according to the present invention comprises a loudspeaker; a feedforward processing section for performing feedforward processing on an electric signal to be inputted to the...
7706547 System and method for noise cancellation  
The invention is directed to a system and method for noise cancellation for an apparatus such as an electric motors or generator. The system may comprise a plurality of actuators, a plurality of...
7103188 Variable gain active noise cancelling system with improved residual noise sensing  
An active noise cancellation system includes a series of features for more effective cancellation, greater reliability, and improved stability. A particular feature adapted for headset systems...
7031460 Telephonic handset employing feed-forward noise cancellation  
A telephonic handset comprises an active noise reduction (ANR) system. The ANR system comprises a reference microphone and an IIR filter. The IIR filter is receivingly coupled to the reference...
6944303 Noise cancellation device, engine-noise cancellation device, and noise cancellation method  
A phase-locked loop (PLL) circuit generates a sine wave signal synchronized with an input signal. The sine wave signal is directly supplied to a first multiplier. The sine wave signal is also...
6688422 Method and apparatus for actively influencing the intake noise of an internal combustion engine  
A method and apparatus for actively influencing the intake noise of an internal combustion engine. The apparatus comprises a controller (7) which senses the actual noise (I) via a microphone (16)...
6625287 Enhancing automatic noise reduction using negative output resistance  
An Automatic Noise Reduction system wherein the Q of the frequency response is reduced using a negative output resistance to substantially eliminate the coil resistance of a speaker in a headset....
6449369 Method and device for hybrid active attenuation of vibration, particularly of mechanical, acoustic or similar vibration  
A filtering device consisting of a nonadaptive feedback filter that generates active attenuation of the vibration on the framework, without generating instability in a first frequency band, and an...
6278786 Active noise cancellation aircraft headset system  
An active noise cancellation aircraft headset system. A speaker is mounted within each earcup of a headset for receiving and acoustically transducing a composite noise cancellation signal. A...
6259792 Waveform playback device for active noise cancellation  
A noise environment is sampled via microphone. A processor generates a cancellation signal to offset the effects of the noise to a listener. The cancellation signal is converted into a sample...
6061456 Noise cancellation apparatus  
Disclosed is a transducer for use in a noise cancellation apparatus for reducing background noise. The transducer includes a housing having first microphone means for receiving a first acoustic...
5848169 Feedback acoustic energy dissipating device with compensator  
An acoustic energy dissipating device (100) comprises an acoustic driver (112) coupled to an acoustic medium and an acoustic sensor (110) for detecting a pressure of the acoustic medium near the...
5781640 Adaptive noise transformation system  
A system for suppressing the effects of undesirable noise from an annoying noise source contains a plurality of transformation sounds which, when combined with the noise form a sound that is...
5638454 Noise reduction system  
A system for reducing periodic noise, which includes a plurality of harmonically related noise signals, comprises an actuator for producing a canceling acoustic signal, a sensor for detecting a...
5627746 Low cost controller  
A simple, low cost active noise cancellation system employing a delay and actuator estimator (35), a gain determination (34), a gain (33) and speaker (36) that cancels stationary random noise such...
5619581 Active noise and vibration cancellation system  
An active noise and vibration control system (20) for cancellation of noise or vibration. The system (20) provides a system whereby the adaptation path and feedforward path are implemented in...
5604813 Industrial headset  
This invention relates to the various features of a headset design that utilizes active noise cancellation. This particular design has been developed to work with radio communication systems, but...
5590206 Noise canceler  
In a noise canceler, a pilot-canceling signal without noise is applied to the inverting input of a subtracter via a first MOS transistor. When a noise signal is present, a pilot signal and noise...
5488666 System for suppressing sound from a flame  
A system for suppressing sound from a flame comprises a detector for detecting a first signal which emanates from the flame. A photo sensor rapidly detects the noise from the flame. The first...
5440642 Analog noise cancellation system using digital optimizing of variable parameters  
A digitally controlled analog cancellation system containing an analog noise cancellation circuit with a residual microphone (39) with a digital virtual earth controller (40) for optimizing...
5412735 Adaptive noise reduction circuit for a sound reproduction system  
A noise reduction circuit for a hearing aid having an adaptive filter for producing a signal which estimates the noise components present in an input signal. The circuit includes a second filter...
5371801 Energy absorption apparatus  
Apparatus for absorbing acoustic energy directed toward a wall. The appars includes a piezoelectric layer intermediate the wall and the source of the acoustic energy. Circuitry attached to the...
5363451 Method and apparatus for the active reduction of compression waves  
An apparatus for reducing noise characterized by a number of input microphones arranged near an undesired noise source, a signal processor coupled to the input microphones and operative to develop...
5315661 Active high transmission loss panel  
An active high transmission loss panel for quieting either one or two way sound radiation which incorporates a number of cells (11) which contain sensors and actuators (12) adapted to be controlled...
5305387 Earphoning  
An earphone for use in an active noise reduction system includes a shell accommodating a microphone closely adjacent to a driver shaped and sized to fit in the concha of an ear.
5276740 Earphone device  
An earphone device includes an acoustic tube having an inner diameter substantially identical to that of the external auditory canal has an ear mounting portion at one end and an acoustic...
5267321 Active sound absorber  
The Active Sound Absorber of the invention is based on an electroacoustical transceiver defined as a bilateral electroacoustical transducer acting as both a diaphragm actuator and motion sensor,...
5221185 Method and apparatus for synchronizing rotating machinery to reduce noise  
A system for reducing noise created by multiple rotating machines by synchronizing the machines so as to establish a phase relationship between the machines which minimizes the noise. One or more...
5182774 Noise cancellation headset  
A headset for acoustic reproduction of an electronic signal which electronic signal is representative of the summation of a desired audio signal and an anti-noise signal. The headset includes a...
5138664 Noise reducing device  
This invention is concerned with a device for reducing the external noise reaching the ear in extremely noisy places such as in the vehicle or construction sites. According to the present...
5047736 Selective interference reduction in transmission lines  
Devices and methods for selectively reducing an electromagnetic or acoustic interference present in a transmission line by an active adaptive means, are described. For the electromagnetic...
5046874 Impact printer print head with active sound pressure attenuation means  
An improved impact printer print head is provided that includes the means for active attenuation of acoustic emission in the vicinity of the print head in a printer. The print head incorporates an...
4985925 Active noise reduction system  
Improvement in active noise reduction based on a negative feedback electro-acoustical system which consists of an Electronic Earplug seated in the concha fossa combining active and passive noise...
4953217 Noise reduction system  
In order to overcome problems in an active noise reduction system of sound buffets at low frequency and signal enhancement caused by imperfect transfer functions of a noise cancelling sound...
4947434 Electronic attenuator  
An electronic attenuator uses a speaker which is sheet-like in shape and is made of a piezoelectric material for generating a reversal sound. The attenuator uses a microphone installed in a noise...
4899387 Active low frequency acoustic resonance suppressor  
An electrically active sound wave attenuation apparatus mounted in an upright, free-standing housing for eliminating unwanted reflected waves in a room. The housing is intended to be placed in a...
4805733 Active silencer  
An active silencer provided in a pipe which has one end reaching the noise source and the other end open, the active silencer being provided with a sound generating means which is provided at the...
H000417 Headset for ambient noise suppression  
The headset system utilizes the theory that unique sound waves can be added or subtracted without loss of information to attenuate the noise at the ear and mouthpiece, without lowering the noise...
4625083 Voice operated switch  
A voice operated switch for use in noisy environments is described. The switch includes independent amplifiers for separately amplifying frequency band limited speech and noise signals. The...
4527282 Method and apparatus for low frequency active attenuation  
A low frequency attenuation method based on the virtual earth system has the driver feeding cancelling waveforms into a partially closed volume which contains the microphone of the virtual earth...
4490841 Method and apparatus for cancelling vibrations  
Methods and apparatus for cancelling both random and repetitive vibrations in gases, liquids or solids. The invention relies on generating cancelling vibrations (S) for a primary vibration to be...
4489441 Method and apparatus for cancelling vibration  
Improved method and apparatus for the nulling of a primary vibration by the "active" method, based on the "virtual earth" system in which the output of a loudspeaker (3') is continually controlled...
4455675 Headphoning  
Headphones have a small cavity between the diaphragm and the ear canal with a microphone in the cavity closely adjacent to the diaphragm providing a feedback signal that is combined with the input...
4449235 Electronic cancelling of acoustic traveling waves  
An acoustic disturbance in a thin support rod may be suppressed by detecting the disturbance, and processing the detected signal with electronic circuits to generate two output signals, which are...
4122303 Improvements in and relating to active sound attenuation  
A primary sound wave in a confined space is attenuated by a secondary sound wave generated to null with the primary wave. The secondary wave is produced by a first electrical signal representing...
4025724 Noise cancellation apparatus  
An array of independent sound cancellation units is arranged over a vibrating noise generating surface. Each unit includes an arrangement of acoustic transducers (sensors) positioned adjacent the...
2983790 Electronic sound absorber  
Matches 1 - 50 out of 51 1 2 >