Abstract: Drive device for manually driving a blind, roller shutter or the like, comprising an epicyclic reduction gearbox consisting of the juxtaposition of two simple planetary gear trains of type I (A1, B1, a1,/A2, B2, a2), the sun wheels (A1, A2) of which are mechanically linked so as to be driven simultaneously at the same speed and the annulus gear (B1) of the first planetary gear train of which, on the input side of the reduction gearbox, is fixed and the other annulus gear (B2) of which can rotate. The reduction ratio is less than or equal to 3. This drive device makes it possible to obtain a low reduction ratio with a small diameter.

Abstract: Drive device for manually driving a blind, roller shutter or the like, comprising an epicyclic reduction gearbox consisting of the juxtaposition of two simple planetary gear trains of type I (A1, B1, a1,/A2, B2, a2), the sun wheels (A1, A2) of which are mechanically linked so as to be driven simultaneously at the same speed and the annulus gear (B1) of the first planetary gear train of which, on the input side of the reduction gearbox, is fixed and the other annulus gear (B2) of which can rotate. The reduction ratio is less than or equal to 3.

Abstract: Reducer comprising at least one stage and associated with a nonreturn device and with an Oldham coupling. The nonreturn device consists of two tubular seats fitted one into the other and of a helical spring braking by expansion against the casing of the reducer. The Oldham cross is seated within the nonreturn device. The reducer, the nonreturn device and the Oldham coupling are seated within the casing and are retained axially in the latter by a ring capable of receiving an adapter piece for mounting the assembly in a frame. The assembly forms a compact unit which can be handled easily.