Camshaft Assembly

A camshaft assembly comprising an inner shaft, a coaxial outer tube rotatable relative to the inner shaft, and two groups of cams mounted on the outer tube, the first group of cams being fast in rotation with the outer tube and the second group of cams being rotatably mounted on the tube and being connected for rotation in phase with the inner shaft by means of connecting members that pass through circumferentially elongated slots in the outer tube, characterised in that the outer tube surrounds the inner shaft with clearance such that the inner shaft is not radially supported by the outer tube at any point along the length of the inner shaft and in that the members connecting different ones of the cams of the second group to the inner shaft are inclined relative to one another and act to locate the axis of the inner shaft relative to the outer tube.