Patent ID: 6918480

Claim:
A centrifugal clutch for coupling a drive shaft to a driven member at rotary speeds above a pre-determined threshold, comprising: a centrifugal slider with a massive enlargement at one end and a first coupling formation; a frame formed to carry the centrifugal slider on formations to constrain it to sliding motion between an extended radial position and a retracted radial position, and to fit fixedly on the drive shaft to be driven by it, with the shaft at right-angles to the axis of sliding motion of the frame; an output drive member mountable for free rotation on the drive shaft and formed for driving engagement with the driven member in use, and formed with a second coupling formation which connects drivingly with the first only when the centrifugal slider is at its extended position; and a return spring acting on the centrifugal slider, and also bearing directly on the drive shaft in use, to bias the centrifugal slider towards its retracted position; whereby rotation of the centrifugal slider and frame causes the massive enlargement to pull the centrifugal slider radially from its retracted to its extended radial position to cause the first and second coupling arrangements to interengage and thus to transmit rotary drive from the drive shaft to the driven member, but the spring causes disengagement when the rotation ceases, so as to decouple the drive shaft from the driven member.