New Transducers Limited

Flat Audio Technologies LLC

Graham Bank

Neil John Harris

Martin Colloms

Henry Firouz Azima

Neil Simon Owen

Julian Fordham

Martin Christopher Cassey

Nicholas Patrick Roland Hill

Paul Antony Burton

Kieron Dunk

Christien Ellis

Farad Azima

Denis Morecroft

Charles Bream

Martin Roberts

Bijan Djahansouzi

Andrew Marchant

David Keith Berriman

Douglas Andrew Marchant

An acoustic device intended to operate pistonically and in bending comprising a panel-form acoustic radiator, a magnetic drive system including a voice coil on a tubular bobbin, the bobbin being directly coupled to the radiator to drive the radiator directly; and a coupling device connected to the bobbin, and to the radiator at a position at or near to the first nodal line of bending resonance of the radiator. A method of improving the on-axis response of a loudspeaker having a panel-form radiator and intended to operate both pistonically and in bending, comprising driving the radiator by a directly connected tubular bobbin, and substantially suppressing the lowest natural frequency of the radiator by providing a coupler connected from the bobbin to the radiator at or near to its first nodal line.

Acoustic device

An acoustic device and method of making said acoustic device. The acoustic device comprises a diaphragm having resonant bending wave modes in the operating frequency range, and a plurality of electromechanical transducers coupled to the diaphragm. The positioning and mechanical impedance of the transducers are such that at least a selected number of the resonant bending wave modes are balanced so that the net transverse modal velocity over the area of the diaphragm tends to zero with the balancing of the resonant bending wave modes being achieved substantially by the positioning and mechanical impedance of the transducers. The parameters of the diaphragm may be such that there are a plurality of nodal grouped locations at or around which the nodal lines of a selected number of resonant modes are clustered. Each transducer may be mounted at one of the plurality of nodal grouped locations.

Bending wave acoustic device and method of making thereof

An acoustic device comprising a diaphragm () having an area and having an operating frequency range and the diaphragm () being such that it has resonant modes in the operating frequency range, an electromechanical transducer having a drive part coupled to the diaphragm () and adapted to exchange energy with the diaphragm, and at least one mechanical impedance means () coupled to or integral with the diaphragm, the positioning and mass of the drive part () of the transducer and of the at least one mechanical impedance means () being such that the net transverse modal velocity over the area of the diaphragm () tends to zero. A method of making an acoustic device having a diaphragm having an area and having an operating frequency range which includes the piston-to-modal transition, comprising choosing the diaphragm parameters such that it has resonant modes in the operating frequency range, coupling a drive part of an electro-mechanical transducer to the diaphragm to exchange energy with the diaphragm, adding at least one mechanical impedance means to the diaphragm, and selecting the positioning and mass of the drive part of the transducer and the positioning and parameters of the at least one mechanical impedance means so that the net transverse modal velocity over the area tends to zero.

Acoustic device and method of making acoustic device

A transducer () for producing a force which excites an acoustic radiator, e.g. a panel () to produce an acoustic output. The transducer () has an intended operative frequency range and comprises a resonant element which has a distribution of modes and which is modal in the operative frequency range. Parameters of the transducer () may be adjusted to improve the modality of the resonant element. A loudspeaker () or a microphone may incorporate the transducer.

Resonant element transducer

An electromechanical force transducer having an intended operative frequency range comprises a resonant element () having a periphery and having a frequency distribution of modes in the operative frequency range, characterized by support means () coupled to the periphery of the resonant element, the support means () having a substantially restraining nature in relation to bending wave vibration of the resonant element (). The transducers may be mounted to an acoustic radiator () in a loudspeaker via coupling means () to excite the acoustic radiator to produce an acoustic output.

Transducer

A bending wave loudspeaker having an operating frequency range and a coincidence frequency which is above the operating frequency range, comprising a resonant panel having two generally orthogonal axes, vibration exciting means coupled to the panel to excite the panel into resonance along the one axis of the panel, and means restraining or preventing resonance along the other axis of the panel whereby the panel radiates an acoustic output which is of wide directivity along the one axis and of narrow directivity along the other axis of the panel.

A magnet assembly having inner and outer yokes of magnetic flux conductive material which together define an annular air gap and a radially oriented magnet sandwiched between the inner and outer yokes such that a first face of a first magnetic polarity contacts the inner yoke and a second face of a second opposite magnetic polarity contacts the outer yoke, characterised by an axially oriented magnet forming part of the magnet assembly, and wherein the radially oriented magnet is annular and has opposed axial ends, and the inner and outer yokes are annular and together enclose one axial end of radially oriented magnet to define the air gap, and wherein the axially oriented magnet is disposed adjacent to the other axial end of the radially oriented magnet, whereby the inner and outer yokes and the axially oriented magnet together reduce flux leakage from the magnet assembly. From other aspects the invention is a moving coil actuator comprising the magnet assembly described above or a loudspeaker incorporating the actuator.

Magnet assembly for loudspeakers

A bending wave loudspeaker includes a transparent acoustic radiator capable of supporting bending wave vibration and an electromechanical force transducer mounted to the acoustic radiator to excite bending waves in the acoustic radiator to produce an acoustic output. The transducer has an intended operative frequency range and includes a resonant element having a frequency distribution of modes in the operative frequency range and a coupler for mounting the transducer to the acoustic radiator. The loudspeaker may be incorporated in a telephone handset or a visual display unit.

Loudspeaker

A bending wave panel-form acoustic radiator formed from sheet material to define an acoustically active area and having at least one integral stiffening member in the form of a corrugation extending out of the plane of the sheet and at least partially across the acoustically active area of the radiator, which stiffening member is of substantially U-shaped cross section. Also disclosed is a method of making a bending wave panel-form acoustic radiator, comprising forming a sheet into a panel having at least one integral corrugation member extending out of the plane of the sheet and at least partly across the sheet and of substantially U-shape cross-section, to stiffen the sheet to have a desired ability to support and propagate bending waves.

Bending wave acoustic radiator

A loudspeaker comprising a phase uncorrelated diffuse sound source and a duct or wave guide coupled to the sound source to direct acoustic energy from the source, the duct or wave guide having a substantially parallel section extending from the vicinity of the sound source and a termination positioned remotely from the panel.

Loudspeakers

A loudspeaker comprising a resonant panel-form member adapted to produce an acoustic output and a vibration exciting system on the panel-form member and adapted to apply bending wave energy thereto, characterized in that the vibration exciting system is adapted to apply a bending couple to the panel-form member.

A touch pad assembly for use in an electronic article. The assembly comprises a touch pad, a coupler for mechanically coupling the touch pad to casing of the electronic article and a transducer which is mounted by coupling means on the coupler or the touch pad to drive the casing as an acoustic radiator. An electronic article can incorporate the same. An electronic article comprises a body in or on which a bending wave loudspeaker is mounted. The loudspeaker comprises a bending wave acoustic radiator and an electromechanical force transducer mounted to the radiator to vibrate the radiator to produce an acoustic output. The transducer has an intended operative frequency range and comprises a resonant element having a frequency distribution of modes in the operative frequency range and coupling means for mounting the transducer to the radiator.

Electronic article comprising loudspeaker and touch pad

A loudspeaker drive unit comprising a resonant acoustic radiator, an exciter on the radiator to apply bending wave energy to the radiator to cause it to resonate, a support for the loudspeaker drive unit, and means resiliently coupling the exciter to the support.

A communication device comprising a microphone, a conduction interface and an electromechanical force transducer mounted to the conduction interface to drive the interface to conduct sound to a user by bone conduction, characterised in that the transducer has an intended operative frequency range and comprises a resonant element having a frequency distribution of modes in the operative frequency range and coupling means for mounting the transducer to the interface.

Growing community of inventors

Woodbridge, United Kingdom

Graham Bank