an article unstacking system includes an infeed conveyor which delivers stacks of articles to an unstacker which has an inclined support wall and a carriage reciprocatively movable parallel to the support wall and carrying a platform disposed in a plane perpendicular to the support wall for cooperation therewith to define a generally v - shaped trough into which the stack is received . the carriage is moved upwardly until the top article is engaged by a discharge roller which lifts it from and peels it off the stack . to facilitate separation of the top article , the stack is retracted a short distance as soon as the top article is engaged by the discharge rollers , so that the carriage undergoes repeated up and down movements until the stack is depleted . carriage drive is effected by short - stroke and long - stroke air cylinders , with the former being carried by the movable element of the latter .