Abstract: A crank assembly for a bicycle includes a crank axle rotatably mounted to a frame of the bicycle, and a carrier shaft slidably mounted on the crank axle and configured to slide in a direction substantially parallel to a central longitudinal axis of the crank axle and relative to the crank axle. The crank assembly also includes an elliptical sprocket mounted on the carrier shaft. The elliptical sprocket rotates to move the bicycle in response to a rotation of the crank axle. A start time of a power stroke of the elliptical sprocket is changed by sliding the carrier shaft relative to the crank axle.

Abstract: A crank assembly for a bicycle includes a crank axle, crank arms mounted to the crank axle to rotate the crank axle, a carrier shaft slidably mounted on the crank axle and configured to slide relative to the crank axle, and a sprocket mounted on the carrier shaft. A position sensor determines a relative position of a diametric axis of the sprocket relative to a central longitudinal axis of the crank arm at an end of a power stroke. Further, an actuator is operatively coupled to the carrier shaft to slide the carrier shaft, and a controller is configured to actuate the actuator to slide the carrier shaft relative to the crank axle based on input from the position sensor to change a start time of the power stroke of the sprocket.

Abstract: A crank assembly for a bicycle includes a crank axle rotatably mounted to a frame of the bicycle, and a carrier shaft slidably mounted on the crank axle and configured to slide in a direction substantially parallel to a central longitudinal axis of the crank axle and relative to the crank axle. The crank assembly also includes an elliptical sprocket mounted on the carrier shaft. The elliptical sprocket rotates to move the bicycle in response to a rotation of the crank axle. A start time of a power stroke of the elliptical sprocket is changed by sliding the carrier shaft relative to the crank axle.

Abstract: A crank assembly for a bicycle includes a crank axle, crank arms mounted to the crank axle to rotate the crank axle, a carrier shaft slidably mounted on the crank axle and configured to slide relative to the crank axle, and a sprocket mounted on the carrier shaft. A position sensor determines a relative position of a diametric axis of the sprocket relative to a central longitudinal axis of the crank arm at an end of a power stroke. Further, an actuator is operatively coupled to the carrier shaft to slide the carrier shaft, and a controller is configured to actuate the actuator to slide the carrier shaft relative to the crank axle based on input from the position sensor to change a start time of the power stroke of the sprocket.

Abstract: A concrete block molding apparatus and component molding parts coated with a flame spray refractory material and binder composition. The coatings can be smoothed to provide a finished surface for the blocks as by polishing, pressure on the coated surface or preferably by a coating of a thermoset resin as a binder. A preferred thermoset resin includes polytetrafluoroethylene (PTFE) in the coating to improve slipperiness. The parts have a greatly increased life cycle and the apparatus has a much longer cycle time between changes of the parts.