(19)
(11) EP 1 014 416 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
12.12.2001 Bulletin 2001/50

(43) Date of publication A2:
28.06.2000 Bulletin 2000/26

(21) Application number: 99204083.2

(22) Date of filing: 02.12.1999
(51) International Patent Classification (IPC)7: H01H 57/00, H01H 83/02, H01H 71/12
(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: 24.12.1998 IT MI982830

(71) Applicant: ABB Ricerca SpA
20099 Sesto San Giovanni (MI) (IT)

(72) Inventors:
  • Mandurino, Pietro
    40141 Bologna (IT)
  • Sciacca, Aldo
    20097 San Donato Milanese (MI) (IT)
  • Colonna, Donato
    20137 Milano (IT)
  • Volponi, Silvia
    20033 Desio (MI) (IT)
  • Bianc, Giuseppe Bertolotto
    10020 Lauriano (To) (IT)

(74) Representative: Giavarini, Francesco 
ABB Ricerca S.p.A. Viale Edison, 50
20099 Sesto San Giovanni (MI)
20099 Sesto San Giovanni (MI) (IT)

   


(54) Residual-current device


(57) A residual current device comprising an actuator which is operatively connected to kinematic elements for opening contacts following the detection, by a sensor, of an earth fault current. The actuator comprises a bistable metallic element which is operatively connected to the kinematic elements and to which at least one piezoelectric element is coupled, the piezoelectric element being excited by an electrical signal as a consequence of the detection of the fault current and inducing a movement of the bistable metallic element from a first stable equilibrium position to a second stable equilibrium position. The device further comprises reset elements which are suitable to return the bistable metallic element into the first stable equilibrium position before the contacts close again.






Search report