Patent ID: 7478810

Claim:
A rotary feeder for conveying enclosures, the feeder comprising: a feeder drum; a drive unit that drives rotation of the feeder drum; a cam-actuated pair of claws mounted at diametrically opposite locations on the feeder drum, wherein the claws are pivoted into an open position counter to a prestressing force of a prestressing means via cam follower rollers and a cam as the drum rotates, and wherein the claws are pivoted into a closed position under the prestressing force of prestressing means as the drum rotates further, such that a claw grips an enclosure border of a respectively lowermost enclosure of an enclosure stack and, as the drum continues to rotate, draws this lowermost enclosure out of the enclosure stack and guides the enclosure around a circumference of the feeder drum; wherein the cam is configured in a first section with an increase in radial spacing of its profile in accordance with a claw-opening movement and in a second section with a decrease in the radial spacing of its profile in accordance with a claw-closing movement, such that a braking moment caused by the claw opening counter to the prestressing force of the prestressing means is compensated for by a substantially simultaneous and substantially equivalent accelerating moment caused by the claw closure under the prestressing force of the prestressing means.