US Patent 8256574 Centrifugally-operated apparatus

Herein is disclosed a centrifugally-operated apparatus that comprises at least a shaft with an axis of rotation and a pawl that is coaxially mounted on the shaft with at least a portion of the pawl being movable radially inwardly and outwardly from the shaft. The axis of rotation of the shaft passes through the pawl, at a location that is radially offset from the center of mass of the pawl. Rotation of the shaft and pawl above a predetermined speed can cause at least the movable portion of the pawl to be moved radially outward from the shaft, in which position an engaging end of the movable portion of the pawl may engage with a component such as a ratchet.