US Patent 7670072 Cam-locking positioning mechanism

A locking positioning mechanism includes a first element and a second element, the first element and second element rotatable relative to one another about a common rotational axis between a locked orientation and an unlocked orientation and axially translatable relative to one another. The mechanism further includes one or more first locking surfaces of the first element and one or more second locking surfaces of the second element. The second locking surfaces are configured to clear the first locking surfaces in the unlocked orientation. The second locking surface is configured for an interference fit with a first locking surface in the locked orientation.