US 5,205,704 A · Apparatus for prefeeding sheets of paperboard products

Abstract

An improved prefeeder assembly for shingling sheets of planar material in which a sheet stack is positioned on a prefeeder lift conveyor which lowers the sheet stack into a floor pit to incrementally elevate the sheet stack. A block pusher assembly sequentially pushes block segments to a conveyor assembly where a shingling assembly shingles the sheets. A bottom sheet removal assembly having an in-path diverter plate contacts and diverts only the bottom sheet of the bottom most block segment as this block segment is being shingled. As shingled sheets are discharged to other process equipment, a tamping assembly actuated by balloon cylinders serve to tamp the sheet edges for uniform restacking.

An improved prefeeder assembly for shingling sheets of planar material from block segments removed from a sheet stack and passing the sheets to a sheet feeder hoppers, the prefeeder assembly supported on a support floor and comprising:

infeed lift conveyor means for receiving the sheet stack substantially at floor level, for lowering the sheet stack below floor level and for selectively lifting the sheet stack so that the block segments can be moved therefrom;
block pusher means for sequentially pushing each block segment from the sheet stack;
conveyor means for receiving block segments and for moving same to discharge the sheets into the sheet feeder hopper, the conveyor means comprising:
a block conveyor having a first end and a second end, the first end of the block conveyor disposed to receive the block segments as the block pusher pushes the block segments from the sheet stack, the second end of the block conveyor disposed to deliver the block segments to the shingling means;
and
block conveyor power means for selectively powering the block conveyor so that a block segment on the block conveyor is moved thereby;
shingling means for shingling the sheets on the conveyor means prior to discharge into the sheet feeder hopper;
bottom sheet removal means for removing the bottom sheet of the last removed block segment from the sheet stack, the bottom sheet removal means comprising:
a diverter plate;
and
diverter actuator means for supporting the diverter plate in a first position and a second position, the diverter plate in the first position is disposed in the path of the shingled sheets so that at least the bottommost sheet on the conveyor means is diverted to pass away from the conveyor means, and the diverter plate in the second position is disposed in clearing relationship to the shingled sheets;
and
wherein the conveyor means further comprises:
a conveyor frame;
a shingle conveyor having first and second ends, the first end of the shingle conveyor pivotally supported by the conveyor frame and disposed to receive shingled sheets from the shingling means, the second end of the shingle conveyor disposed to discharge shingled sheets into the sheet feeder hopper;
shingle conveyor power means for powering the shingle conveyor to move the shingled sheets therealong;
and
conveyor support and pivoting means for supporting the second end of the shingle conveyor and for selectively pivoting same to an elevated position and to a substantially horizontal position, the conveyor support and pivoting means comprising:
at least one fluid cylinder having an extended position and a retracted position;
at least one support structure supported by the floor and having a vertically extending first member with a top end portion and a second member with an inclined guide surface;
a free hanging member pivotally connected to the shingle conveyor, the free hanging member disposable to be disposed along the inclined guide surface when the shingle conveyor is in the horizontal position and the free hanging member caused to be pulled up the inclined guide surface as the shingle conveyor is being moved to the elevated position by the fluid cylinder so that the free hanging member is caused by gravity to hang from the shingle conveyor to be disposed over the top end of the first member of the support structure, the second end of the shingle conveyor supportable substantially at the elevated position thereof by the free hanging member extending upward from the first member of the support structure;
and
fluid means for alternatively positioning the fluid cylinder in the extended position and in the retracted position.

20 more elements

Apparatus for prefeeding sheets of paperboard products

Life of this patent

Apparatus for prefeeding sheets of paperboard products

Life of this patent

Abstract

Claims16