Face spline clutch

An infinitely variable transmission comprising

• a rotational input,
• a rotational output,
• a mode shift apparatus including
• a first side coupled to the rotational input, the first side including a first engagement surface having an imaginary center corresponding generally to the axis of rotation of the input, the first engagement surface formed to include a number of radially extending channels that increase in size as they extend radially,
• a second side coupled to the rotational output, the second side including a second engagement surface having an imaginary center corresponding generally to the axis of rotation of the rotational input, the second engagement surface formed to include a number of radially extending splines that increase in size as they extend radially, the radially extending splines sized to engage the channels of the first engagement surface, the second side forming a spur gear including a number of teeth positioned about the periphery of the gear with the splines positioned on a face of the spur gear with each spline defining an axis that is generally perpendicular to a longitudinal axis of the teeth of the spur gear, and
• a hydraulically powered actuator acting on the first side to move the first side between a first position in which the first and second engagement surfaces are disengaged such that rotation between the first and second sides is independent, and a second position in which the first and second engagement surfaces are engaged such that rotation is transferred from the first side to the second side.