Clutch or brake system for a torque transmission with a planetary gear

A clutch or brake system for a torque transmission having an input arranged for connection to a drive source, and an output arranged for connection to a load, the clutch or brake system including:

• a first rotatable unit connectable to the input or output, including at least one first abutment surface;
• a second rotatable unit connectable to the output or input, respectively, including at least one gripping member having at least one second abutment surface arranged for selectively engaging the first abutment surface, the first and second abutment surfaces being adapted to each other so as to allow disengaging under load;
• a third rotatable unit including at least one retaining member having a plateau and a ramp to the plateau, the third rotatable unit being arranged for selectively being in one of one or more first rotational positions or one of one or more second rotational positions relative to the second rotatable unit, wherein the at least one retaining member in a first rotational position locks the at least one second abutment surface in a first disposition for rotationally coupling the second rotatable unit to the first rotatable unit, and in a second rotational position releases the at least one second abutment surface to a second disposition for decoupling the second unit from the first unit;
• wherein the third rotatable unit includes a first actuation member arranged for moving the third rotatable unit from a first position to a second position and a second actuation member arranged for moving the third rotatable unit from a second position to a first position relative to the second rotatable unit;
• a fourth unit including a selector, the selector being arranged for selectively being in a first mode or second mode,
• the selector in the first mode being arranged for gripping the first actuation member for rotating the third rotatable unit from a first position to a second position relative to the second rotatable unit;
• the selector in the second mode being arranged for gripping the second actuation member for rotating the third rotatable unit from a second position to a first position relative to the second rotatable unit;
• the second rotatable unit including a retractor member arranged for moving the first and/or second actuation member out of engagement with the selector;
• wherein the at least one second abutment surface and the retractor member are angularly positioned such that while the at least one second abutment surface moves from the second disposition to the first disposition the first actuation member is kept out of engagement with the selector by a trailing end of the retractor member when the at least one gripping member contacts the at least one retaining member at a border between the ramp and the plateau, and the first actuation member is released from the retractor member when the at least one gripping member reaches the plateau of the at least one retaining member.