Patent ID: 8513845

Claim:
A tubular electric motor unit ( 10 ) for roll-up elements such as blinds, curtains or similar items, of the type intended to be housed inside a winding tube ( 11 ) of the roll-up element, comprising a tubular body ( 12 ) inside which a geared motor ( 13 ) is housed with a drive output at one end of the tubular body ( 12 ) and a limit stop unit ( 14 ) at the other end, wherein for the transmission of the movement of rotation to the limit stop unit ( 14 ) there is a first transmission ring ( 15 ) that is fitted so that said first transmission ring ( 15 ) can be rotated on a protruding portion of the limit stop unit ( 14 ) to couple kinetically with the limit stop unit ( 14 ), said first transmission ring has an external peripheral surface coupled peripherally with minimal clearance with an inside surface of the winding tube of the roll-up element, said first transmission ring ( 15 ) being able to be opened and closed again for replacement on the limit stop unit ( 14 ), said tubular electric motor unit having a second transmission ring ( 25 ) with an external peripheral surface coupled peripherally with minimal clearance with the inside surface of the winding tube and said second transmission ring is fitted, coaxially to the tubular body ( 12 ), on a rotary head ( 27 ) that is set in rotation by the geared motor, wherein said first transmission ring ( 15 ) and said second transmission ring ( 25 ) are identical to each other and comprise on their internal peripheral surface both means ( 28 ) of engagement with the rotary head and means ( 18 ) of kinetic coupling with the limit stop unit ( 14 ) so that said first transmission ring ( 15 ) and said second transmission ring ( 25 ) are indistinctly interchangeable with each other, wherein the means of engagement of the second transmission ring ( 25 ) on the rotary, head comprise grooved couplings ( 28 ) to be inserted in complementary grooved couplings ( 29 ) on a periphery of the rotary head and the means of kinetic coupling with the limit stop unit ( 14 ) comprise a ring gear ( 18 ) joined by said grooved couplings ( 28 ) to couple with a complementary cogwheel ( 19 ) in the limit stop unit ( 14 ).