Motorized actuator and movable barrier provided with said actuator

Motorized drive configured to open and/or close a wing of a barrier wherein the motorized drive comprises an electric motor and a reduction unit through which the electric motor can operate the wing opening and closing and wherein:

• the reduction unit comprises a first and a second toothed profile engaging together, thus forming a gear with a variable transmission ratio depending on the angular and/or linear position of at least one of the two toothed profiles;
• and
• at least one of the first and of the second toothed profile forms at least one toothed section having a pitch profile which is substantially non-circular;
• wherein the first toothed profile comprises teeth along an entire circumference thereof and is configured to fully rotate around a first rotation axis that is located within the first toothed profile and has a pitch profile comprising a shape defined by points, each point being at a distance from said first rotation axis and determined based on the Minimum Values_3 and the Maximum Values_3 indicated in Table 11B, the Minimum Values_3 and the Maximum Values_3 being unitless and uniformly scalable, wherein said distance and said pitch profiles are considered in a plane perpendicular to the first rotation axis, wherein the second toothed profile has a substantially arched shape delimited by a first and a second end and is configured to rotate around a second rotation axis that is located within the second toothed profile when the first and the second toothed profile are engaged at or near a substantially middle portion between the two ends of the second toothed profile, the contact point between the first and second toothed profile is at a maximum distance from the first rotation axis.