Timing-range gear

A centrifugal force governed valve timing device used as a compact integral part of an internal combustion engine for adjusting at least one of an advancing and a retarding of a relative angular position of a driven camshaft with respect to an angular position of a driving crankshaft, the camshaft having a central longitudinal axis, said device includes a camshaft drive means comprising:

• an inner-hub member having an axial bore for removably interfacing the camshaft, a first circular cavity coaxial to said bore extending inward from a first planar mating surface for receiving existing engine components, a circular load-bearing periphery, a flange extending outward form said circular load-bearing periphery and having a second planar mating surface, and a first radial cavity means extending from said first planar mating surface to said second planar mating surface and extending radially inward from said circular load-bearing periphery for receiving and coaperatively interacting with a slidable flyweight means;
• an outer-hub member, in a phased relation to a crankshaft, having a circular central cavity with a journaling surface ending at a flat-bottom thereof for slidably receiving and rotatably interacitng with said inner-hub member through said first and second planar surfaces and said circular load-bearing periphery thereof, and having a second radial cavity means extending radially outward from the journaling surface;
• said slidable flyweight means includes at least one member, each said member including a phasing portion, said phasing portion including a rounded corner, said rounded corner engaging a corresponding phasing surface of the second radial cavity means of said outer-hub member, wherein a sliding action of the slidable flyweight means is translated into angular displacement between said inner-hub and outer-hub members;
• and a spring means disposed to interact with said slidable flyweight means.