Results
author = "Lemarquand, Guy"
New structure of loudspeaker
Author(s) :
Lemarquand, Guy
Description :
We present a new structure of loudspeaker: the motor is ironless, the suspension is ferrofluidic, the moving part is piston like, with a concave dome. The absence of iron guarantees a small and constant inductance of the moving coil, as well as the absence of Eddy currents. The motor includes two ci...
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Language(s) :
English
Ironless loudspeakers
Author(s) :
Lemarquand, Guy
Description :
We note the drawbacks of classical loudspeaker motors: the inductance varies with the coil's position, there is a reluctant effect and Eddy currents appear because of the iron in the motor. We then present ironless structures of loudspeaker motors to eliminate these drawbacks. These structures are s...
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HAL - Hyper Article on Line
Language(s) :
English
Discussion about the magnetic field produced by cylindrical halbach structures
Description :
This paper uses a three-dimensional analytical approach based on the Coulombian model for studying the magnetic field produced by cylindrical Halbach structures. Such structures, commonly used in magnetic couplings or in electrical machines, are composed of tile permanent magnets with rotating magne...
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Language(s) :
English
Analytical Expression of the Magnetic Field Created by Tile Permanent Magnets Tangentially Magnetized and Radial Currents in Massive Disks
Description :
In this paper, we present new expressions for calculating the magnetic field produced by either tile permanent magnets tangentially magnetized or by radial currents in massive disks. These expressions are fully analytical, that is, we do not use any special functions for calculating them. In additio...
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Language(s) :
English
Modelling an Ironless Loudspeaker by Using Three-Dimensional Analytical Approaches
Description :
This paper presents some improved three-dimensional expressions of the magnetic field created by tile permanent magnets uniformly and radially magnetized for the design of ironless loudspeaker structures. All the expressions determined have been reduced to compact forms. We use these expressions for...
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Language(s) :
English
Mechanical Properties of a Ferrofluid Seal: Three-Dimensional Analytical Study based on the Coulombian Model
Description :
This paper presents a general method for studying the mechanical properties of a ferrofluid seal by using a three-dimensional analytical approach based on the coulombian model of a magnet. The fundamental Maxwell's equations lead us to define the concept of magnetic energy of the ferrofluid seal by ...
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Language(s) :
English
Design of ironless loudspeakers with ferrofluid seals: analytical study based on the coulombian model
Description :
This paper presents an analytical method based on the coulombian model of a magnet for studying a ferrofluid seal in ironless electrodynamic loudspeakers. Such an approach differs from the ones generally used for studying such geometries because the ferrofluid used is submitted to a very high magnet...
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Language(s) :
English
Mechanical Properties of a ferrofluid seal: three-dimensional analytical study based on the coulombian model
Description :
This paper presents a general method for studying the mechanical properties of a ferrofluid seal by using a three-dimensional analytical approach based on the coulombian model of a magnet. The fundamental Maxwell's equations lead us to define the concept of magnetic energy of the ferrofluid seal by ...
Repository :
HAL - Hyper Article on Line
Language(s) :
English
Comparison of the coulombian and amperian current models for calculating the magnetic field produced by radially magnetized arc-shaped permanent magnets
Description :
This paper presents some improved analytical expressions of the magnetic field produced by arc-shaped permanent magnets whose polarization is radial with the amperian current model. First, we show that the radial component of the magnetic field produced by a ring permanent magnet whose polarization ...
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HAL - Hyper Article on Line
Language(s) :
English
Magnetic Couplings With Cylindrical and Plane Air Gaps: Influence of the Magnet Polarization Direction
Description :
We present a synthesis of cylindrical magnetic couplings realized with tile permanent magnets whose polarizations can be radial, tangential or axial. The expressions of the torque transmitted between the two rotors of each coupling have been determined by using the coulombian approach. All the calcu...
Repository :
HAL - Hyper Article on Line
Language(s) :
English