Patent ID: 8904683

Claim:
Device for successively changing elongated flexible objects ( 100 - 400 ) from an active viewable position to a non-active, non-viewable position, said device comprising: a rotatable drum ( 1 ) to which the flexible objects ( 100 - 400 ) are attached, a motor ( 11 ) arranged for driving the rotatable drum ( 1 ) in two opposing rotational directions comprising a first direction where the flexible objects ( 100 - 400 ) are unwound from the drum ( 1 ) and a second direction where the flexible objects ( 100 - 400 ) are wound up on the drum ( 1 ), a controller unit ( 13 ) for controlling the rotational speed and direction of the motor ( 11 ), a balancing spring ( 16 ; 116 ), and a freewheeling clutch ( 17 ; 117 ) mechanism operatively connected to the balancing spring in such a way that i) when the drum ( 1 ) is being rotated in the first direction where the flexible objects ( 100 - 400 ) are unwound from the drum ( 1 ), the freewheeling clutch ( 17 ; 117 ) engages with the balancing spring ( 16 ; 116 ) forcing the balancing spring ( 16 ; 116 ) to take increasing load, and ii) when the drum ( 1 ) is being rotated a first amount in the second direction where the flexible objects ( 100 - 400 ) are wound up on the drum ( 1 ), the balancing spring ( 16 ; 116 ) assists in rotating the drum ( 1 ) until the balancing spring ( 16 ; 116 ) has no inherent load, and when the rotation of the drum ( 1 ) in the second direction proceeds further beyond the first amount in the second direction where the balancing spring ( 16 ; 116 ) has no inherent load, no preloading of the balancing spring ( 16 ; 116 ) occurs.