Delivery and ejection device for flat elements into a machine working them

A delivery and ejection device for receiving flat elements from a production machine which produces a plurality of parallel streams of flat elements exiting the machine on a first conveyor moving at a first speed, with the elements in each stream arranged in an overlapping, shingled configuration, the device comprising:

• a second conveyor moving at a second speed which is slower than the first speed, the second conveyor being positioned to receive the streams from the first conveyor, and as a consequence of the speed difference, to cause an increased overlap of the flat elements in each stream, whereby the streams become compacted as they pass onto the second conveyor;
• a third conveyor positioned to receive the compacted streams from the second conveyor;
• a stacking station including a plurality of stack-forming assemblies,
• wherein each stack-forming assembly:
• is positioned to receive a respective one of the streams from the third conveyor;
• is selectively adjustable to a first configuration in which it is operative to compact the stream into a stack and to eject the stack to a position further downstream, and also adjustable to a second configuration in which it is operative to divert the stream to a fourth conveyor when elements in the stream are determined to be defective;
• and
• a stream interrupting mechanism that introduces spacing into each stream to delineate portions of the streams which will form successive stacks, the stream interrupting mechanism being comprised of:
• a first adjusting device that is operative to lengthen and shorten a portion of the second conveyor which carries the streams;
• a second adjusting device that is operative to lengthen and shorten a portion of the third conveyor which carries the streams,
• the first and second adjusting devices being operative simultaneously and at the same rate of change, to lengthen the carrying portion of one of the second and third conveyors and to shorten the carrying portion of the other of the second and third conveyors;
• and
• a gripping device selectively operable to stop passage of the streams from the second conveyor to the third conveyor, the resulting space introduced between successive elements in the streams serving to delineate the portions of the streams which will form successive stacks;
• and
• a drive mechanism for the third conveyor which is operative to move the third conveyor at the same speed as the second conveyor to receive the stream from the second conveyor, and to move the third conveyor faster than the second conveyor when delineated portions of the streams are being delivered to the stacking station.