Board turner apparatus and method capable of multiple turn inspection

Abstract

The board turner apparatus and method is capable of turning a board over several times for repeated inspection of both sides of such board for more accurate grading of such board before allowing the board to be conveyed forward past a retractable stop. The retractable stop means when extended above the conveyor engages the leading edge of the board at a fixed stop position along a conveyor means and keeps the board from advancing along the conveyor means until such stop means is retracted. The board inverter means includes a plurality of curved turner arms which pivot about the axis of a common support shaft between a lowered position below the upper surface of the conveyor and a raised position above such upper conveyor surface. The turner arms engage the leading edge of the board and cause it to pivot backwards about its trailing edge when such turner arms are pivoted from their lowered position to the raised position in an opposite direction to the movement of the conveyor until the board falls backward onto the conveyor, at a location rearwardly of the stop position. In one embodiment, the retractable stop means is a plurality of stop members separate from the inverter arms. However, in a second embodiment, the stop means is provided by stop surfaces in notches on the free ends of the inverter arms which partially project above the surface of the conveyor in the extended position of the stop means, and are moved down below the surface of such conveyor in the retracted position of such stop means.