A closing device includes a torque storing mechanism, a first and a second actuation member which are both rotatable with respect to the supporting frame and a mechanical connector piece which is rotatable with respect to the supporting frame and configured for being mechanically fixed to the second hinge member which is fixed to the closure member. A first locking mechanism enables to lock the mechanical connector piece either to the first actuation member or to the second actuation member and a second locking mechanism enables to lock the supporting frame to the second actuation member when the connector piece is locked to the first actuation member and to the first actuation member when the connector piece is locked to the second actuation member. In this way, the closing device is suited for left and right turning closure members without requiring an extra gearing to reverse the rotation direction.

A fixation seat having a first guiding element and a second guiding element mounted inside of a hinge mechanism is mounted at a wall or a frame's surface. A first guided assembly and a second guided assembly are mounted at the fixation seat and respectively guided by the first guiding element and the second guiding element to move away from each other or move back. A movable assembly comprises a movable and pivotable shaft mounted through the fixation seat and optionally connected to the first guided assembly or the second guided assembly. A door is mounted at the movable assembly and pivots relative to the surface through the shaft. The movable assembly lifts and lowers the door via the shaft, connected one of the guided assemblies, guided by the guiding elements, so the hinge mechanism is adaptable to install the door at left-side or right-side surfaces.

A transmission assembly for converting a garage door operator (GDO) from a ceiling mounted configuration to a jackshaft configuration by operably coupling the transmission assembly to a motorhead configured to be employed in either the ceiling mounted configuration or the jackshaft configuration may include an output coupler to operably couple the transmission assembly to a drive tube rotatable to alternately open and close a sectional door, the output coupler comprising an output pinion, an input coupler to operably couple the transmission assembly to a motor output shaft of the motorhead, the input coupler comprising an input pinion, a flexible coupling member operably coupling the input pinion and the output pinion, a transmission housing configured to extend around at least a portion of each of the input pinion, the output pinion and the flexible coupling member, and a multi-position coupling bracket having a wall interface portion for rigid connection to a wall, a transmission interface portion to hold the transmission housing relative to the wall interface portion at a first selected angle, and a motorhead interface portion to operably couple the wall interface portion relative to the motorhead at a second selected angle.