Device for winding and unwinding a sun screen or the like, comprising at least one electric motor connected to an external power supply by means of a power cable provided with a connector determining an internal interface plane and fitting in a removable manner into a recess arranged in an external interface plane of a stator of the electric motor, such that its internal interface plane comes into contact with an internal interface plane determined in said recess and being parallel to its external interface plane and located at a distance X from the latter, said device being characterised in that it includes at least: - a support plate configured to be fixed to a wall of a building, - a spacer fixed to said support plate and supporting the connector such that the internal interface plane of the latter is parallel to said support plate and located at a distance A from the latter, - a first interface part fixed to the support plate and determining an internal interface plane parallel to said support plate and located at a distance B from the latter, said first interface part comprising an orifice extending perpendicular to said internal interface plane, and - a second interface part comprising a projecting portion extending perpendicularly from an external interface plane parallel to said support plate, and determining an internal interface plane parallel to its external interface plane and located at a distance C from the latter, said second interface part being fixed to the stator such that its internal interface plane comes into contact with the external interface plane of said stator and that its portion is inserted into said orifice until its external interface plane comes into contact with the internal interface plane of said first interface part, and in that said spacer, first interface part and second interface part are shaped such that the difference between the value of the distance A and the sum of the respective values of distances B and C is equal to the value of distance X. - a support plate configured to be fixed to a wall of a building, - a spacer fixed to said support plate and supporting the connector such that the internal interface plane of the latter is parallel to said support plate and located at a distance A from the latter, - a first interface part fixed to the support plate and determining an internal interface plane parallel to said support plate and located at a distance B from the latter, said first interface part comprising an orifice extending perpendicular to said internal interface plane, and - a second interface part comprising a projecting portion extending perpendicularly from an external interface plane parallel to said support plate, and determining an internal interface plane parallel to its external interface plane and located at a distance C from the latter, said second interface part being fixed to the stator such that its internal interface plane comes into contact with the external interface plane of said stator and that its portion is inserted into said orifice until its external interface plane comes into contact with the internal interface plane of said first interface part, and in that said spacer, first interface part and second interface part are shaped such that the difference between the value of the distance A and the sum of the respective values of distances B and C is equal to the value of distance X.