Signature feeder having improved signature extraction
AssigneeMcCain Manufacturing Corporation
InventorsGeorge Higgins, James Wrona
Life of this patent
Estimating the term…
Abstract
A sheet feeder has a supply station wherein signatures fresh from the printing press are stacked. The stack is supported such that the signatures are in an arched, non-planar configuration. A sheet stripper extracts signatures successively from the stack and feeds them in a constant stream to a transfer conveyor. The stripper grips the sheets with a suction device which applies a constant but locally intermittent vacuum. The transfer conveyor carries the signatures to a delivery station. The delivery station includes fingers which arch the signatures. Arching the signatures in the supply and delivery stations prevents rolling of the signatures.
Claims22
A machine for feeding signatures, having a first lap and a second lap joined at a backbone, to a delivery station, comprising:
- a supply station in which the signatures are to be first loaded in a flat stack with the backbones perpendicular to the direction the signatures will be withdrawn, the supply station including support means for eliminating rolling of the signatures as they depart the supply station, the support means including a pile plate and a riser block mounted on the pile plate, the riser block having a width sufficiently less than the width of the signatures such that the edges of the signatures hang down over the sides of the riser block toward the pile plate, imparting a curvature to the signatures in the stack, the curvature being perpendicular to the direction the signatures will be withdrawn;
- a signature stripper means engageable with the foremost signature of the stack for extracting signatures successively from the stack in the supply station;
- and
- transfer means for receiving signatures from the stripper means and advancing them in a stream to the delivery station.
In a machine for feeding signatures, having a first lap and a second lap joined at a backbone, from a supply station to a delivery station, a method of eliminating rolling of the signatures as they depart the supply station comprising the steps of:
- stacking the signatures in the supply station with the backbones perpendicular to the direction the signatures will be withdrawn;
- engaging the central portion such that the edges of the signatures in the supply station hang downwardly, thereby imparting a curvature to the stacked signatures, the curvature being perpendicular to the direction the signatures will be withdrawn;
- extracting signatures successively from the stack in the supply station;
- and
- advancing signatures extracted from the stack to the delivery station.
A machine for feeding signatures, having a first lap and a second lap joined at a backbone, to a delivery station, comprising:
- a supply station in which the signatures are to be first loaded with the backbones perpendicular to the direction the signatures will be withdrawn, the supply station including support means, engageable with the central portion of the signatures such that the edges hang downwardly from the central portion, said support means eliminating rolling of the signatures as they depart the supply station by imparting a curvature to the stacked signatures, the curvature being perpendicular to the direction the signatures will be withdrawn;
- a signatures stripper means engageable with the foremost signature of the stack for extracting signatures successively from the stack in the supply station;
- and
- transfer means for receiving signatures from the stripper means and advancing them in a stream to the delivery station.
A machine for feeding sheets to a delivery station, comprising:
- a supply station in which the sheets are to be first loaded in a stack;
- a sheet stripper means engageable with the foremost sheet of the stack for extracting sheets successively from the stack in the supply station;
- and
- transfer means for receiving sheets from the stripper means and advancing them in a stream to the delivery station;
- the sheet stripper means including a vacuum source, traveling suction means for carrying sheets from the stack to the transfer means, the suction means having at least two discrete locations at which the vacuum can be applied for gripping the foremost sheet, and cycling means for supplying the vacuum to the discrete locations of the suction means such that the vacuum is constantly present at at least one location but at each specific location the vacuum is applied during at least two time intervals to a particular sheet being carried, with an intervening period between said two time intervals wherein the vacuum is removed from said specific location.
In a machine for feeding sheets from a supply station to a delivery station, a method of extracting sheets from the supply station comprising the steps of:
- stacking the sheets in the supply station;
- extracting sheets successively from the stack in the supply station by applying traveling suction means to the foremost sheets of the stack at at least two discrete locations and supplying a vacuum to the discrete locations such that the vacuum is constantly present at at least one of said locations but at each particular location the vacuum is applied during at least two time intervals to a particular sheet being carried, with an intervening period between said two time intervals wherein the vacuum is removed from said particular location;
- and
- advancing sheets extracted from the stack to the delivery station.
Dependencies are inferred from the claim text.