US 4,615,249 A · Apparatus for trimming stacks of paper sheets or the like

Abstract

A machine for trimming the edges of stacked paper sheets at a trimming station has a conveyor which delivers successive stacks to the trimming station, several knives which are movable from raised positions to lower end positions to thereby trim the respective edges of a stack at the trimming station, anvil blocks which are penetrated into by the cutting edges of the knives when the knives complete their working strokes subsequent to trimming of a stack, and a control unit which prevents the knives from contacting the respective blocks if the knives perform working strokes in the absence of a stack at the trimming station. The control unit can shift the working strokes of the knives and/or lower the blocks to thus ensure that the cutting edges of the knives are arrested short of the respective blocks when a photocell detects the absence of a stack at the trimming station while the knives perform their working strokes.

Claims10

Dependent claims

Apparatus for trimming the edges of stacks of paper sheets or analogous commodities delivered to at least one trimming station, comprising conveyor means for delivering successive commodities to the trimming station;

at least one knife arranged to perform recurrent working strokes during each of which the knife moves from a first to a spaced-apart second position to thereby trim an edge of a commodity at said station;
drive means for moving the knife between said positions in substantial synchronism with the anticipated arrival of commodities at said station, said drive means including a linkage connecting said knife with a motor;
an anvil block located in the path of movement of and being normally engaged by the knife when the latter completes a working stroke;
and control means actuatable to prevent engagement between the knife and the block without interrupting operation of said drive means when the knife completes a working stroke in the absence of a commodity at said station, said control means including means for shifting the knife, and said shifting means being disposed in said linkage.

1 more element

Dependencies are inferred from the claim text.

Apparatus for trimming stacks of paper sheets or the like

Life of this patent

Apparatus for trimming stacks of paper sheets or the like

Life of this patent

Abstract

Claims10