linear coupling mechanism for coupling the brake booster piston to the adjustment means in order to apply variable force to the brake booster piston application_number US 201113993073 A description fig1 shows a schematic view of the electromechanical brake booster under consideration in the text which follows identical reference signs denote identical components the brake booster under consideration comprises a brake booster piston 10 which exerts an assistance force on a brake master cylinder 100 in order to brake the vehicle 200 not shown the assistance force of the brake booster piston 10 is produced during the interaction of an electric motor 20 with an adjustment means 50 and is then transmitted to the brake booster piston 10 via a coupling mechanism 40 which interacts with the adjustment means 50 and implements a variable transmission ratio of the coupling mechanism 40 depending on its position the coupling mechanism 40 operates according to a simple lever arm principle in which the pulling force of the adjustment means 50 on the coupling mechanism 40 is intensified in proportion to the length of the lever arms of the coupling mechanism 40 the electric motor 20 is arranged above the brake booster piston 10 with the axis of symmetry of the brake booster piston 10 and the axis of symmetry of the electric motor 20 lying in a common vertical plane the output shaft of the electric motor 20 is formed by a threaded spindle 30 which extends substantially parallel to the axis of symmetry of the brake.