Electro-mechanical pivot wing drive for pivoting wings of doors or the like

An electro-mechanical rotary leaf drive for pivotal leaves for doors comprising:

• an elongated housing,
• an electric motor and a transmission adjoining said electric motor as an axial extension thereof and in said housing,
• said transmission having an intermediate output shaft drivingly connected with a bevel transmission, said bevel transmission having an output drive shaft arranged transversely of said elongated housing and adapted for coupling with a linkage for driving a pivotal leaf,
• a restoring spring unit acting on the output drive shaft,
• said restoring spring unit comprising a helical spring having at least thirty turns and a spring moment during an opening movement of the rotary leaf which increases less than 100% as a maximum, said helical spring surrounding one of said electric motor and said transmission and at a drive output end thereof bearing against an entrainment means, said entrainment means being connected in such manner as to prevent relative rotation with said intermediate shaft, and
• means for deenergizing said electric motor during the entire closing phase of the pivotal leaf to obtain a generator effect and consequent damping during the door closing phase.