Rotational control apparatus

Apparatus for providing rotational control comprising, in combination:

• a first member;
• a second member;
• a third member, with the first, second and third members being rotatable relative to each other about an axis;
• a first interface element axially slideable relative to but rotatable with the first member;
• a second interface element rotatable with the second member;
• a piston mounted to and axially moveable relative to the third member;
• a bearing including first and second races, with the first race extending axially and including first and second axial ends, with the second race having L-shaped cross sections including an axially extending annular portion extending generally parallel to but radially spaced from the first race, with the second race further including a radially extending annular portion extending from the axially extending annular portion and having a radially inner extent corresponding to the first axial end of the first race, with the bearing further including a plurality of balls located between the first race and the axially extending annular portion of the second race, with the second axial end of the first race abutting with one of the piston and the first interface element and the radially extending annular portion abutting with the other of the piston and the first interface element, with the piston being movable from a disengaged position where the first and second interface elements are allowed to be axially separated to an engaged condition with the piston through the bearing moving the first interface element to engage the second interface element with axial forces being applied directly through the bearing.