Method of extracting and accelerating flat objects

摘要

A method of extracting and accelerating flat objects such as postal items which are presented in the outlet position of an unstacking head for use by a machine downstream therefrom, the method making use of a clamp for grasping postal items one-by-one and of various sensors (7) such as photoelectric cells, serving to indicate the presence of a postal item in the outlet position of the unstacking head, or in the field of action of the clamp, or serving to indicate that the clamp is in a waiting position or in an end-of-stroke position, the method being characterized in that it essentially comprises the following stages: moving the clamp to a waiting position; when the presence of a postal item is expected in the outlet position from the unstacking head, driving the carriage towards the outlet position of the unstacking head; when the presence of the postal item is detected within the field of action of the clamp, the clamp is closed and the carriage is driven towards the downstream machine; as soon as the presence of a postal item is no longer detected in the outlet position of the unstacking head, the clamp is unclamped, thereby releasing the postal item; and the carriage is stopped and returned to the waiting position.