Modular Single-Fork Lumber Stacking Machine

A lumber stacking machine, comprising:

• a conveyor for transporting a series of boards of varying thickness;
• a lift table for receiving the boards from the conveyor stacked into layers;
• a stacker comprises a board width sensor for detecting widths of the boards as they travel along the conveyor, a controller for receiving boards width measurements from the board sensors, a rail, a carriage movable along the rail, a fork supported by the carriage, and an adjustable stop for selectively blocking movement of the boards to force the boards to drop off the rail as the rail retracts while carrying a layer of the boards;
• wherein the controller comprises a microprocessor and a memory storing non-transient computer-executable instructions which, when executed by the microprocessor, causes the microprocessor to:
• (a) determine or obtain widths of boards traveling on the conveyor;
• (a) position the carriage in response to the widths of a plurality of the boards to assemble a layer of the boards on the fork,
• (b) set the adjustable stop in a first position to position a leading edge of the layer,
• (c) retract the carriage a sufficient distance to drop a first board of the layer onto the stack,
• (d) determine a desired spacing between the first board of the layer and a second board of the layer,
• (e) set the adjustable stop in a second position to impart a desired spacing between the first and second boards,
• (f) retract the carriage a sufficient distance to drop the second board of the layer onto the stack with the desired spacing between the first and second boards.