Patent ID: 7262532

Claim:
A multi-rotor motor structure having hermetically separated first and second modules, wherein the first module comprises an electronically commutated external-rotor motor ( 20 ), having an internal stator ( 22 ) that is arranged on a bearing tube ( 30 ) and that is separated by a first air gap ( 24 ) from an external rotor ( 26 ; 92 ), a rotor cup ( 40 ), forming part of said external rotor, that is open at one end and is joined at its other end to a shaft ( 46 ) that is journalled in the bearing tube ( 30 ), a permanent-magnet arrangement ( 76 ), arranged at the open end of the rotor cup ( 40 ), for magnetic interaction with a second permanent-magnet rotor ( 92 ) forming part of said second module and rotatably journalled in the motor structure, which permanent-magnet arrangement ( 76 ) is separated from that second rotor ( 92 ) by a second air gap and forms with it a magnetic coupling ( 94 ), so that a rotation of the permanent-magnet arrangement ( 76 ) brings about a rotation of that second rotor ( 92 ), and a non-ferromagnetic separating element ( 82 ) arranged in the second air gap, wherein: said separating element hermetically separates the second rotor ( 92 ) from the external-rotor motor ( 20 ); said separating element is formed with a support ( 106 ) for journalling the second rotor ( 92 ), as well as with a support for the bearing tube ( 30 ; 134 ) for journalling the shaft ( 46 ; 46 ′) of the rotor cup ( 40 ); said separating element seals off a rotor-cup-remote end of said bearing tube ( 30 ); and said shaft ( 46 ; 46 ′) of said rotor cup ( 40 ) is secured ( 54 , 59 ) against axial removal from said bearing tube ( 30 ).