High speed revolving board singulator with retracting shoe and variable dwell duckers

A lug loader comprising:

• a first shaft rotatably mounted transversely across a board flow path, wherein a board in said board flow path is aligned transversely across said board flow path and translates in a downstream direction on a board infeed transfer from an upstream position,
• a board supporting structure mounted to said first shaft so as to rotate with rotation of said first shaft, said board supporting structure having a shoe mounting surface generally orthogonal to said first shaft and having a radially outer-most rim, radially outer-most relative to said first shaft, said rim generally circumferentially contiguous so as to form a board supporting surface around said rim,
• an elongate shoe having first and second ends, a board supporting heel mounted thereon, said shoe pivotally mounted at said first end of said shoe to said shoe mounting surface, a cam follower mounted to said shoe so as to protrude from said shoe away from said shoe mounting surface,
• a selectively rotatable cam mounted on a cam support, said cam cooperating with said cam follower, said cam independently selectively rotatable relative to said first shaft, said cam having a cam surface lying generally in a first plane adjacent to and generally parallel with said shoe mounting surface, said cam surface a radial cam distance from said cam support, said rim a radial rim distance from said cam support, said radial cam distance less than said radial rim distance, said cam surface defining a first cam lobe, said first cam lobe asymmetric and radially extended about said cam support relative to a non-extended circumference of said cam surface, said first cam lobe generally on an upstream side of said cam, said non-extended circumference of said cam generally on a downstream side of said cam, said cam lobe selectively rotatable, by selective rotation of said cam by a cam actuator, between an upwardly rotated shoe actuating position and a downwardly rotated shoe non-actuating position, said cam follower lying generally in said first plane and cooperating with said cam surface so as to ride over, in surface following contact with, said cam surface on said upstream and downstream sides of said cam, as said board supporting structure rotates about said first shaft relative to said cam, said cam lobe when in said shoe actuating position driving said board supporting surface on said shoe radially outwardly of said rim as said cam follower rides over said cam surface corresponding to said cam lobe.