Method of stacking continuously arriving sheets

A method of operating an apparatus for stacking sheets and having:

• conveyor means having a downstream end spaced upstream in a horizontal transport direction from a stacking station for delivering the sheets continuously one after the other at a predetermined upper level in the direction to the station;
• a main platform vertically displaceable in the stacking station between an upper position below the upper level and a lower position;
• an auxiliary platform below the upper level and formed by a plurality of transversely spaced and parallel rods horizontally displaceable in the direction between an extended position in the station above the main platform, a retracted position upstream of the main platform, and between an upper position just below the upper level and a lower position therebelow;
• a plurality of vertically extending separator elements between the conveyor means downstream end and the stacking station and having bent-over upper ends projecting downstream between the rods in the transport direction and displaceable between
• a separating position projecting into the station between the auxiliary platform and the upper level and engageable between trailing edges of the sheets in the station,
• a withdrawn position out of the station between the station and the conveyor means downstream end,
• an upper position with the upper ends just below the upper level, and
• a lower position with the upper ends level with the upper position of the auxiliary platform, each element having a vertical length greater than the vertical distance between the auxiliary platform and the upper level,
• the method comprising the steps, when a sufficiently tall stack is formed in the station, of sequentially
• raising the elements into their upper positions and advancing the elements into their separating positions,
• lowering the elements into their lower positions while maintaining them in their separating positions to form in the stack a gap level with the auxiliary platform,
• advancing the auxiliary platform into its extended position while the elements are in their lower and separating positions, so as to support the stack above the gap and retracting the elements to their withdrawn positions,
• lowering the main platform, removing the stack therefrom, and raising the main platform to its upper position, and
• withdrawing the auxiliary platform to its retracted position to deposit the stack on it onto the main platform.