(19)
(11) EP 0 353 369 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
06.03.1991 Bulletin 1991/10

(43) Date of publication A2:
07.02.1990 Bulletin 1990/06

(21) Application number: 88312396.0

(22) Date of filing: 29.12.1988
(51) International Patent Classification (IPC)5: H01H 13/10, H01H 13/52, H01H 1/24
(84) Designated Contracting States:
AT BE CH DE ES FR GB GR IT LI LU NL SE

(30) Priority: 01.08.1988 US 227310

(71) Applicant: Wu, I-Long
Taichung (TW)

(72) Inventor:
  • Wu, I-Long
    Taichung (TW)

(74) Representative: Parry, Christopher Stephen et al
PAGE, WHITE & FARRER 54 Doughty Street
London WC1N 2LS
London WC1N 2LS (GB)


(56) References cited: : 
   
       


    (54) Keyswitch


    (57) A keyswitch includes a pushbutton (1, P, 1a, 1b) and a conductive coil spring (2, S, 2a, 2b) for supporting the pushbutton (1, P, 1a, 1b) on the upper end of the spring (2, S, 2a, 2b). The lower part of the spring (2, S, 2a, 2b) is in the shape of a conical helix. When the pushbutton (1, P, 1a, 1b) is depressed, the spring (2, S, 2a, 2b) forms a conductive path between two terminals (3 and 3, A and B, 3a and 8a, 3b and 3b).







    Search report