Positioning control device of two elements (22, 23) with each other, for example the blades of a cutting tool of the pruning shears class, of which one of them (23) is fixed and the other (22), mobile and mechanically connected to a gearmotor (21) in order to be dragged by the latter along a preset path, the position of said movable member (22) being subject to the position of a control member (24) such as a trigger, said device including a carrier frame of the fixed element (23), characterized in that it comprises a control circuit (3) of the geared motor (21), a first fixed Hall effect sensor (40), connected to the circuit of control (3), fixedly installed in relation to the frame, suitable for capturing, with a straight permanent magnet (41), supported by the movable element (22), a position of zero or negative distancing of the two elements (22, 23) , and a second Hall effect sensor (42), connected tado to the control circuit (3), fixedly installed in relation to the frame, suitable for capturing, with a permanent permanent magnet supported by the mobile element (22), a position of maximum distance of the two elements, because the magnet (41 ) is positioned so that its north-south axis is perpendicular to its trajectory, because the first sensor (40) is arranged in an area according to which the magnetic field vector of this first magnet has a component perpendicular to said north axis -sur, said first sensor (40), for its sensitive face, parallel to the north-south axis of the associated magnet (41), and is capable of giving two position information, namely, abscissa and orderly, of the magnet (41 ) associated, in a fixed Cartesian reference in relation to said sensor, and because the latter has two Hall effect cells that form an angle between them, said cells being, by their sensitive faces, parallel to the north-south axis of the magnet associate (41), and why The value of the minimum or negative distance between the moving element (22) and the fixed element
