Stacking apparatus

An apparatus for stacking sheets of asbestos cement interleaved with patterns, comprising feeding means for feeding fresh asbestos cement sheets, first and second flanking guideways for guiding respectively pattern-carrying trolleys and trolleys carrying mixed stacks of sheets interleaved with patterns, a bridge structure arranged above said guideways and said feeding means, a carriage displaceably mounted on the said bridge structure and provided with respective suction boxes for picking up, transporting and depositing the said sheets and the patterns, a trolley elevator in the area where the stacks of interleaved sheets and patterns are formed, wherein the improvement consists in the provision at the station where the mixed stack of sheets and patterns is formed on the respective trolley, under the bridge structure, of a section of auxiliary guideway, disposed above the second guideway for the mixed stack-carrying trolley, at a higher level than the maximum height attainable by the top of the mixed stack when said trolley is on said second guideway, a transfer mechanism for transferring said trolleys from the first guideway to the auxiliary guideway, and means for disengaging the section of auxiliary guideway from the trolley when the latter is engaged by the said elevator such that said elevator lowers the trolley onto the second guideway.