Abstract: A discharge unit for sequentially discharging a lowermost piece of a stack of said pieces superposed in a shaft. The pieces in the stack have the same dimension as the inner cross section of the shaft and the shaft has a lower end wherefrom the lowermost pieces are sequentially discharged. The lower shaft end defines a plane and an axle extends in this plane. A bell crank lever having a first arm and a second arm is supported on the axle for pivoting between a first position wherein the first arm projects into the inner cross section of the shaft to hold the lowermost piece in the shaft and a second position wherein the first arm is retracted out of the inner shaft cross section to release the lowermost piece for discharge from the shaft. The second bell crank lever arm is arranged to clamp the piece of the stack superposed over the lowermost piece in position when the first bell crank lever arm is pivoted into the second position to hold the stack in the shaft.