118 results about "Electrodynamic loudspeaker" patented technology

A method of estimating diaphragm excursion of an electrodynamic loudspeaker may be performed using audio signals. An audio output signal may be applied to a voice coil of the electrodynamic loudspeaker through an output amplifier to produce sound. A detected voice coil current and a determined voice coil voltage may be applied to a linear adaptive digital loudspeaker model that has a plurality of adaptive loudspeaker parameters. The parameter values of the adaptive loudspeaker parameters may be computed based on the linear adaptive digital loudspeaker model and applied to a non-linear state-space model of the electrodynamic loudspeaker. For the non-linear state-space model, a predetermined non-linear function may be applied to at least one of the plurality of received parameter values to compute at least one non-linearity compensated parameter value of the adaptive loudspeaker parameters, to determine an instantaneous excursion of the diaphragm.

The invention belongs to the high-temperature off-gas temperature measurement technical field, in particular to an apparatus adopting the acoustics to measure the temperature of off-gas in a hearth. A set of sound-wave transceiver comprising a sound-wave duct, an electric speaker and a reinforced microphone is respectively arranged onto the symmetrical positions of the wall on two sides of the boiler hearth; the electric speakers send out sound signals which are simultaneously received by the reinforced microphone of the same side or the opposite side and are converted into voltage signals; after the voltage signals pass through a signal regulator, the signals are input through a cable into a double-channel data collecting card to be converted into digital signals; then a cross correlation is adopted for analysis to obtain the time-of-flight of sound wave and finally the computer and software are adopted to figure out the temperature of off-gas. The work of the apparatus is not limited by the high-temperature, dusts, corrosion and onflow and the like. complicated and rigid conditions in the boiler and the apparatus is provided with the features of non-insertion style, accuracy, real-time and portable measurement; and the apparatus can replace the traditional hearth high-temperature probes and can in time judge the combustion condition of the boiler for regulation and control.

The present invention relates in one aspect to a method of detecting diaphragm excursion of an electrodynamic loudspeaker. The method comprises steps of generating an audio signal for application to a voice coil of the electrodynamic loudspeaker and adding a high-frequency probe signal to the audio signal to generate a composite drive signal. The method further comprises a step of applying the composite drive signal to the voice coil through an output amplifier and detecting a modulation level of a probe signal current flowing through the voice coil.

A feedback cancellation assembly for an electroacoustic communication apparatus may include a signal transmission path for generation and emission of an outgoing sound signal to an external environment through an electrodynamic loudspeaker and a signal reception path comprising a microphone for generation of a microphone input signal corresponding to sound received from the external environment. The signal reception path may generate a digital microphone signal. The outgoing sound signal may be acoustically coupled to the microphone. An electronic feedback cancellation path may be coupled between a tapping node and a summing node to produce a feedback cancellation signal to the summing node.

A method of detecting enclosure leakage of an electrodynamic loudspeaker mounted in an enclosure or box may include applying an audio signal to a voice coil of the electrodynamic loudspeaker through an output amplifier and detecting a voice coil current flowing into the voice coil. A voltage across the voice coil may be detected and an impedance or admittance of the loudspeaker across a predetermined audio frequency range may be detected based on the detected voice coil current and voice coil voltage. A fundamental resonance frequency of the loudspeaker may be determined based on the detected impedance or admittance and compared with a nominal fundamental resonance frequency of the loudspeaker representing a sealed state of the enclosure. Acoustic leakage of the enclosure may be detected based on a deviation between the determined the fundamental resonance frequency and the nominal fundamental resonance frequency of the electrodynamic loudspeaker.

Electro-dynamic loudspeakers typically include a diaphragm having a conductor applied to one of its surfaces where the diaphragm is secured to a frame. The conductor is connected to a power supply for providing electrical current through linear traces of the conductor that interact with magnetic fields generated by magnets that are mounted to the frame. The diaphragm is driven by a motive force created when current passes through the conductor within the magnetic field. The electrical current is varied to create an acoustical output from the electro-dynamic loudspeaker.

The invention belongs to the technical field of on-line temperature monitoring of a wall cooled wall, and particularly relates to a system for monitoring the fire facing side wall temperature of a water cooled wall of a power station boiler on line, and a monitoring method. The section of a furnace is provided with sound wave receiving and sending systems, each sound wave receiving and sending system consists of a sound wave guide pipe, an electrodynamic loudspeaker, and a special electret microphone; and receiving and sending measurement points of the sound wave receiving and sending systems are distributed on a heating side of the same side of the water cooled wall. The method comprises the following steps of: sending sound signals by the electrodynamic loudspeaker, receiving the sound signals and converting the sound signals into voltage signals by an enhanced microphone simultaneously, allowing the voltage signals to pass through a cable input signal conditioner and enter a data acquisition card, and converting the voltage signals into digital signals; obtaining time of flying by generalized cross correlation time delay estimation; and calculating the fire facing side wall side temperature of the water cooled wall by a computer and software. The system is not limited by severe environments such as high temperature, corrosion, dustiness and the like in the furnace, can truthfully reflect the fire facing side wall side temperature of the water cooled wall, avoids pipe explosion phenomena, and reduces accident rate and operation cost.

A mounting apparatus for attaching a device like an electro-dynamic loudspeaker to a mounting location in an automobile or other vehicle. The mounting apparatus employs bracket hardware that is either affixed to or integral with the loudspeaker that is to be mounted. The mounting apparatus can position the loudspeaker in a fixed angular orientation, or enable the angular orientation of the loudspeaker to be variable, as desired, to achieve the optimum performance of the loudspeaker.

The present invention relates in one aspect to a voice coil temperature protector for electrodynamic loudspeakers. The voice coil temperature protector comprises an audio signal input for receipt of an audio signal supplied by an audio signal source and a probe signal source for generation of a low-frequency probe signal. A signal combiner is configured to combine the audio signal with the low-frequency probe signal to provide a composite loudspeaker drive signal comprising an audio signal component and a probe signal component. The voice coil temperature protector comprises a current detector configured for detecting a level of a probe current component flowing through the voice coil in response to the composite loudspeaker drive signal and a current comparator which is configured to comparing the detected level of the probe current component with a predetermined probe current threshold. The predetermined probe current threshold corresponds to a predetermined voice coil temperature via a known temperature dependency of a voice coil resistance. The voice coil temperature protector further comprises a signal controller configured for attenuating a level of the audio signal in response to the probe current component falls below the predetermined probe current threshold.

The present invention provides a loudspeaker diaphragm and an electrodynamic loudspeaker of an elongated shape being shorter in the minor-axis direction than in the major-axis direction, which have a desirable sound reproducing capability with a high efficiency and are not significantly influenced by divided vibrations of an elongated loudspeaker diaphragm, and which are suitably installed in devices such as display devices. In the elongated loudspeaker diaphragm: the diaphragm body includes a first diaphragm portion in a central portion of a rear surface thereof, the first diaphragm portion including a junction to a voice coil bobbin, a second diaphragm portion extending on each side of the first diaphragm portion in the major-axis direction, and a reinforcement rib extending continuously through the first diaphragm portion and the second diaphragm portions; and the edge includes a free edge portion for freely supporting opposite ends in the minor-axis direction of the first diaphragm portion and the second diaphragm portion, and a fixed edge portion being thicker than the free edge portion for fixedly supporting a distal end of each second diaphragm portion in the major-axis direction.

Heat-sound refrigeration machine includes connected noise collector, heat exchanger in heat end, heat-sound plate pile, heat exchanger in cold end, resonating tube and resonant cavity. There are various noise sources including electroacoustic (such as electrodynamic loudspeaker), heat-sound source (such as standing wave type and traveling wave type heat-sound driver) and pneumatic sound source. Consuming available energy is common point of these sound sources (electrical energy, heat energy and kinetic energy). Purpose of the invention is to correct ubiquity noise to drive heat-sound refrigeration machine so as to change wastes into valuables. One directional reflection type oxhorn shaped sound channel is utilized to correct and magnify noise in environment to raise sound pressure level to reach requirement of Heat-sound refrigeration system.

Electro-dynamic loudspeakers typically include a diaphragm having a conductor applied to one of its surfaces. The diaphragm is secured to a frame. The conductor is connected to a power supply for providing electrical current through linear traces of the conductor that interact with magnetic fields generated by magnets that are mounted to the frame. The diaphragm is driven by a motive force created when current passes through the conductor within the magnetic field. The electrical current is varied to create an acoustical output from the electro-dynamic loudspeaker. Different methods of tensioning the diaphragm are provided for simplifying the manufacturing process and for assuring proper diaphragm tension.

The present invention relates in one aspect to a method of controlling or limiting diaphragm excursion of a loudspeaker. The method comprising steps of receiving a first audio signal and deriving an excursion signal representing diaphragm excursion of the electrodynamic loudspeaker from the first audio signal. The method additionally comprises deriving an excursion envelope from the excursion signal and applying a second audio signal, derived from the first audio signal, to an input of an adjustable low-frequency suppressor. The second audio signal is filtered by the adjustable low-frequency suppressor to selectively attenuate low-frequency components based on the excursion envelope to produce a processed audio signal with reduced low-frequency content.

The invention relates to a thin type electrodynamic loudspeaker. The loudspeaker comprises a speaker frame, and a magnetic circuit structure, a positioning support chip and a voice cone which are installed in the speaker frame, wherein the speaker frame is provided with a wiring board. The loudspeaker is characterized in that the magnetic circuit structure comprises a U-shaped magnetic conducting yoke, a magnet, a magnetic pole core and a voice coil, wherein the U-shaped magnetic conducting yoke is arranged in the speaker frame, and the outer bottom surface of the U-shaped magnetic conducting yoke is tightly combined with the upper bottom surface of the speaker frame; the magnet and the magnetic pole core are installed in the U-shaped magnetic conducting yoke, the lower surface of the magnet is tightly combined with the inner surface at the bottom of the U-shaped magnetic conducting yoke, and the upper surface of the magnet is tightly combined with the magnetic pole core; the voice coil is wound around the magnet and the magnetic pole core, a space is reserved between the inner wall of the voice coil and the outer wall of the magnetic pole core, and a space is also reserved between the outer wall of the voice coil and the inner wall of the U-shaped magnetic conducting yoke. The invention has the advantages of artful structure, compactness and reasonableness, optimizes the thickness while not decreasing the magnetic flux and the BL value, and can not produce excessive heat energy, thereby ensuring the acoustic performance and the reliability of the loudspeaker.

The invention provides an electric array satellite sound and vibration integrated simulation test system, which is characterized by comprising an electric array sound field simulation system and a vibration simulation test system, wherein the electric array sound field simulation system is used for providing noise excitation and collecting sound signals; and the vibration simulation test system isused for providing vibration excitation and collecting acceleration signals. The electric array sound field simulation system comprises an electric loudspeaker array (1), wherein the electric loudspeaker array (1) comprises audio devices; the audio devices comprise loudspeakers; and a plurality of audio devices and a plurality of loudspeakers are arranged. The invention provides a sound and vibration test system, which is short in period and low in cost, for accomplishing a satellite mechanical environment test, the test period of satellite mechanical environment test simulation is greatly shortened, a complex mechanical environment of the coupling between noise and vibration in a radome during the satellite launching process can be simulated more authentically, the test efficiency is improved, the test cost is reduced, and test technical requirements of the satellite mechanical environment are met.

An electrodynamic speaker in which the number of steps of forming a tinsel wire to be connected to a voice coil and connecting the tinsel wire to a terminal can be reduced is provided.A frame of the electrodynamic speaker includes an edge mounting section, a magnetic circuit mounting section, a coupling section for coupling the edge mounting section and the magnetic circuit mounting section so as to define a plurality of window sections, a terminal fixing section for fixing a terminal, and at least one void for dividing the edge mounting section having an approximately annular shape, the void being communicatively connected to the window sections of the coupling section. A middle portion of the tinsel wire passes through the void or the window sections communicatively connected to the void, and the other end of the tinsel wire is connected and fixed to the terminal.

An air conduit device with an active noise reduction function comprises a noise space side air conduit and a noise reduction space side air conduit, wherein the noise space side air conduit and the noise reduction space side air conduit communicate with each other; the noise reduction space side air conduit is a double-layered conduit which includes an inner-layer conduit and an outer-layer conduit respectively; the outer-layer conduit sleeves the inner-layer conduit; a ventilating interlayer is formed between the inner-layer conduit and the outer-layer conduit; at least one noise sensor is mounted on the edge of the noise space side air conduit or in the noise space side air conduit; an electrodynamic loudspeaker is mounted in the inner-layer conduit; the noise sensor and the electrodynamic loudspeaker are connected with a noise reduction control circuit respectively; and the noise reduction control circuit receives noise signals from the noise sensor and drives the electrodynamic loudspeaker. Since the sound wave plane of a secondary sound source is parallel to that of noise, the air conduit device can obtain a favorable wideband noise suppression effect; and an air circulating port is formed near a noise canceling section, so that the air conduit device can achieve an obvious noise suppression effect while guaranteeing the ventilation quantity.

An electro-dynamic loudspeaker is provided with dampening arrangements that contribute to improved acoustical properties for the electro-dynamic planar loudspeaker. The dampening arrangements include providing a frame having a curved sidewall surface for reducing standing waves. Another design provides for a ferrofluid being disposed between the diaphragm and magnets of the electro-dynamic loudspeaker in order to dampen the resonance frequency of the device. In addition, a diaphragm of an electro-dynamic loudspeaker is provided with a short turn of conductor disposed along a fringe zone at an edge of the diaphragm in order to electro-dynamically dampen the edge resonance of the film.

An electrodynamic loudspeaker assembly having an electrodynamic loudspeaker and first and second compensation filters. The electrodynamic loudspeaker includes a voice coil arranged in an air gap of a magnetically permeable structure and a compensation coil wound around a portion of the magnetically permeable structure. The first compensation filter filters an audio input signal to the loudspeaker assembly with a first frequency response to generate a voice coil compensation signal for application to the voice coil. The second compensation filter filters the audio input signal to the loudspeaker assembly with a second frequency response to generate a second compensation signal for application to the compensation coil. The first and second frequency responses, across a predetermined audio frequency range, suppress a time-varying or AC magnetic flux in the air gap caused by voice coil current such that magnetic flux modulation in the air gap of the loudspeaker is suppressed.

A method of estimating diaphragm excursion of an electrodynamic loudspeaker may be performed using audio signals. An audio output signal may be applied to a voice coil of the electrodynamic loudspeaker through an output amplifier to produce sound. A detected voice coil current and a determined voice coil voltage may be applied to a linear adaptive digital loudspeaker model that has a plurality of adaptive loudspeaker parameters. The parameter values of the adaptive loudspeaker parameters may be computed based on the linear adaptive digital loudspeaker model and applied to a non-linear state-space model of the electrodynamic loudspeaker. For the non-linear state-space model, a predetermined non-linear function may be applied to at least one of the plurality of received parameter values to compute at least one non-linearity compensated parameter value of the adaptive loudspeaker parameters, to determine an instantaneous excursion of the diaphragm.

The invention discloses a motor-driven speaker and a vibrating diaphragm provided by the invention which is used in the symmetrical magnetic field and metal coil of the vibrating diaphragm is charged with alternating current. The vibrating diaphragm of the invention comprises an insulation membrane and the metal coil which is distributed on the membrane and adopts pure copper or an alloy mainly containing copper as raw material. The making method of the vibrating diaphragm comprises the steps that: the insulation membrane, the pure copper or the alloy mainly containing copper are first prepared; the pure copper or the copper alloy is processed into the metal coil with the thickness between 0.009 and 0.1mm; the metal coil is fixed with the insulation membrane by a certain winding method. The making method of the invention firstly applies the copper into the vibrating diaphragm as material of the metal coil and due to the excellent conductivity and density of the copper, the excellent sound quality can be provided; additionally, the invention also provides necessary optimum technical parameters such as thickness, density, co-ordination, etc., when the copper is adopted in the making method, thereby breaking the routine thought and overcoming the technical barriers.

The invention discloses an indoor relative humidity on-line monitoring system and a humidity calculation method in the field of environment index monitoring. A sound wave measurement system consisting of an electric loudspeaker, a microphone, a temperature sensor and a pressure sensor is arranged on each of opposite wall surfaces indoor; the electric loudspeaker on one side sends a sound signal; the sound signal is detected by the microphone on the same side; then the sound signal is received by the microphone on the opposite wall surface indoor; the received sound signal is converted into a voltage signal; after being input into a signal conditioner through a cable, the voltage signal enters a data acquisition card so as to be converted into a digital signal; the sound wave transmission time is calculated by a time delay algorithm; and therefore, the indoor transmission speed of a sound wave can be calculated. Furthermore, the indoor temperature and the indoor pressure are detected by probes of the pressure sensor and the temperature sensor which are arranged on two wall bodies. Finally, the indoor relative humidity is calculated through a main control machine. The indoor relative humidity on-line monitoring system can accurately measure the whole indoor average humidity in real time and record the change of the indoor humidity in real time.

The invention belongs to the technical field of online monitoring of temperature of liquid aluminum in an aluminum ladle after vacuum aluminum discharge, and particularly relates to a temperature online monitoring system for liquid aluminum in the aluminum ladle based on acoustic temperature detection and a method. A sound wave conduit, an electric loudspeaker and a microphone are arranged in the same vertical section in the middle of both sides of the aluminum ladle. The electric loudspeaker sends a sound signal which is transmitted to the aluminum ladle by the sound wave conduit and penetrates through the liquid aluminum. The sound signal is received by the microphone and converted into a voltage signal which is input to a signal conditioner through a cable and enters a data collecting card from a junction box to be converted into a digital signal so as to calculate a sound wave flying time and finally calculate the temperature of the liquid aluminum in the aluminum ladle. According to the temperature online monitoring system for the liquid aluminum in the aluminum ladle based on acoustic temperature detection and the method provided by the invention, the continuously changing temperature of liquid aluminum can be truly reflected so that the inner quality of cast aluminum is improved. The system is not affected by severe environment such as high temperature of aluminum ladle, strong corrosion of liquid aluminum and dust, and can be remotely operated to the benefit of controlling and saving labor. Meanwhile, injury of operators caused by field temperature detection can be avoided.

Electro-dynamic loudspeakers typically include a diaphragm that is secured to a frame and has a conductor applied to at least one surface of the diaphragm. The conductor is connected to a power amplifier for providing electric current through the linear traces of the conductor that interact with magnetic fields generated by magnets that are mounted to the frame. The interaction between the current passing through the conductor and the magnetic fields cause vibration in the diaphragm that creates the sound that is heard from the electro-dynamic loudspeaker. Different methodologies of forming the conductor are provided for simplifying the manufacturing process and for locating the conductor closer to the magnetic field generated by the magnets.