(19)
(11) EP 1 096 830 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
02.05.2003 Bulletin 2003/18

(43) Date of publication A2:
02.05.2001 Bulletin 2001/18

(21) Application number: 00309554.4

(22) Date of filing: 30.10.2000
(51) International Patent Classification (IPC)7: H04R 7/12, H04R 31/00
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 29.10.1999 GB 9925674
09.03.2000 US 521911

(71) Applicant: KEF Audio (UK) Limited
GB-Maidstone Kent ME15 6PQ (GB)

(72) Inventors:
  • Anthony, Philip Jeffrey
    Singleton Ashford, Kent TN234 4YR (GB)
  • Wright, Julian Roger
    Matfield, Kent TN12 7LB (GB)

(74) Representative: Molyneaux, Martyn William 
Wildman, Harrold, Allen & Dixon 11th Floor, Tower 3, Clements Inn,
London WC2A 2AZ
London WC2A 2AZ (GB)

   


(54) High frequency transducer


(57) A high frequency transducer 10 having a dome diaphragm 52 with a configuration of a bisected ellipse to overcome the distortion and breaking point of prior art domes even at frequencies above 30kHz. The dome diaphragm having an annular skirt 54 extending therefrom in an integral fashion and connecting to a disc shaped plate 30 of the transducer. A voice coil 60 of cylindrical section is directly connected to the skirt at a region of close proximity to said dome. The dome is constructed of a rigid material such as a metal, an alloy, a metalloid such as, but not limited to, titanium, aluminum, and boron, or a combination thereof. The dome is constructed in accordance with a general formula for an ellipse (x2/a2)+(y2/b2)=1, and a>b, wherein a is half of the length of a major axis and b is half of the length of a minor axis of the ellipse.






Search report