Cylinder for driving mechanisms, the cylinder comprising a main body having a cavity, a rotating body rotatably housed in said cavity and having an axis of rotation along a longitudinal development direction of said cylinder, and a cam, rotatably fixed to said main body and selectively couplable to said rotating body to rotate about said axis of rotation rigidly with said rotating body, wherein said cylinder comprises: - a coupling element structured to alternatively assume a coupling position in which it couples said cam with said rotating body and a decoupling position in which it does not couple said cam with said rotating body, - an actuator structured to move said coupling element from said decoupling position to said coupling position, - an electric power supplier electrically connected to said actuator, - a handling body rotatably fixed to said main body and structured to rotate said cam about said axis of rotation at least when said coupling element is in said coupling position, wherein said electric power supplier is housed inside said handling body and said handling body comprises an access opening to said electric power supplier configured to allow reversible extraction/insertion of said electric power supplier through said access opening and realized on a face of said handling body facing away from, and distal from, said cam or on a surface of said handling body with substantially longitudinal development, wherein said actuator is a linear actuator acting along a longitudinal direction, wherein said actuator comprises a thrust element mechanically connected to said coupling element in such a way that a displacement of said thrust element from an at-rest position to a thrust position gives to said coupling element a thrust force towards said cam or towards said rotating body, wherein said actuator comprises an electric motor electrically connected to said electric power supplier and to a command and control unit, characterized in that said thrust element is in form of a rod having a main development direction along said axis of rotation, and in that said electric motor is structured to rectilinearly displace said thrust element from said at-rest position distal from the cam to said thrust position proximal to the cam. - a coupling element structured to alternatively assume a coupling position in which it couples said cam with said rotating body and a decoupling position in which it does not couple said cam with said rotating body, - an actuator structured to move said coupling element from said decoupling position to said coupling position, - an electric power supplier electrically connected to said actuator, - a handling body rotatably fixed to said main body and structured to rotate said cam about said axis of rotation at least when said coupling element is in said coupling position, wherein said electric power supplier is housed inside said handling body and said handling body comprises an access opening to said electric power supplier configured to allow reversible extraction/insertion of said electric power supplier through said access opening and realized on a face of said handling body facing away from, and distal from, said cam or on a surface of said handling body with substantially longitudinal development, wherein said actuator is a linear actuator acting along a longitudinal direction, wherein said actuator comprises a thrust element mechanically connected to said coupling element in such a way that a displacement of said thrust element from an at-rest position to a thrust position gives to said coupling element a thrust force towards said cam or towards said rotating body, wherein said actuator comprises an electric motor electrically connected to said electric power supplier and to a command and control unit, characterized in that said thrust element is in form of a rod having a main development direction along said axis of rotation, and in that said electric motor is structured to rectilinearly displace said thrust element from said at-rest position distal from the cam to said thrust position proximal to the cam.