Improvements in or relating to Mechanism for Cutting or Severing Sheets or Tubes of Paper.
Year: 1899

page_text: Date of Application, 25th Oct., 1899-Accepted, 30th Dec., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to Mechanism for Cutting or Severing
Sheets or Tubes of Paper.
We, BIBBY & BARON LIMITED, of New Bridge Paper and Paper Bag Works,
Bury, in the County of Lancaster, and JOB DUERDEN, of 69, Bankfield, Bury,
aforesaid, Manager to the said Firm, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement and accompanying
drawings;
Our said invention relates to improvements in mechanism for cutting or
severing continuous lengths of paper, either flat, folded, or in the form of
a tube, so as to produce separate sheets or tubes as is well understood.
The first part of our invention has for its object to improve the cutting
arrangements of machines in which such cutting arrangements sever the paper
at right angles to its longitudinal travel.
In paper cutting arrangements at present in use having revolving cutters it is
necessary in order to cut square to provide means to twist or turn the rotary
cutter out of parallel with the drawing rolls in proportion to the shear of the
blade so that such rotary cutters cannot be driven by gearing but must be
operated by bands. If the rotary cutter is arranged parallel with the drawing
rolls then the paper is not cut square but at a slight diagonal.
According to our invention we arrange for the cutter shaft to remain parallel
with the drawing rolls and yet obtain a square cut and this we do by mounting
the rotary cutter on a cone or conical carrier and so as to act against a fixed
blade.
The second part of our invention relates to means for severing sheets or
tubes of paper with a curved cut by means of a thin curved blade mounted on a
revolving carrier.
Our invention will be clearly understood from the following description in
which reference is had to the annexed two sheets of drawings.
Referring in the first place to Sheet 1 of the drawings.
In the said drawings.
Fig. 1 is a view of the drawing rolls together with a rotary cutting knife and
fixed blade constructed and arranged in accordance with our invention.
Fig. 2 is a front view of the conical cutting knife and fixed blade.
Fig. 3 is a diagramatic plan view.
Fig. shows a slight modification.
In carrying our invention into effect instead of arranging the shaft of the
rotary cutter out of line with the drawing rolls we mount the shaft of the
rotary cutter in bearings parallel with the drawing rollers aa as clearly indicated
in Figs. 1 and 3. The rotary cutting blade is secured to a conical carrier or
tapered roller d so that the Knife edge at the lesser end of the cone is always a
little in advance of the edge at the larger end of the cone as will be readily
understood. Below the revolving cone we mount a fixed inclined blade c

page_text: secured to adjustable brackets f g by means of bolts so that for every revolu-
tion of the rotary cutter the knife c comes into contact with the blade e and
severs a. sheet or tube of paper with a clean straight cut. The edge of the
knife cat the smaller end of the cone is set back a little so that the edge at
the larger end first encounters the fixed blade e the cutting action of the full width
of the knife following as the carrier & revolves. Whilst this cutting or severing
action is taking place the paper p is being fed forward by the drawing rolls a a
to such an extent as to be about equal to the advance of the knife at the smaller
end of the cone so that the action of the knife severs the passing sheet or tube
with a cut at right angles to the longitudinal traverse of the paper. It will
be obvious that were the knife e mounted on a cylindrical carrier and given
slicar the passing sheet would be severed at a slight diagonal and not with a
cut at right angles, but by securing the knife to a conical carrier we are enabled
to cut quite square and yet give considerable shear to the knife.
Prior to our invention in order to give shear to the knife so as to obtain
effective cutting it has been necessary to twist or arrange the rotary cutter out
of parallel with the drawing rolls this being very objectionable interfering as
it does with the direct driving of the cutter. By mounting the knife con a
conical carrier we are enabled to set the shaft b parallel with the drawing
rolls a a, drive direct keeping the gearing in a straight line, and yet cut
perfectly square. In addition to this by utilising a tapered carrier we are
enabled to give considerably more shear to the knife than has heretofore been
possible so that cutting is rendered easier and less strain is put on the machine.
Instead of employing the form of cutter shown in Fig. 1 of the drawings
we may utilise a thin flexible steel cutter i clamped to the conical carrier d
by a plate as clearly indicated in Fig. 4. A cutter of this type is much more
easily sharpened and can be readily reversed so as to present a fresh cutting
edge when desired. We find that a thin flexible cutter such as severs the
paper more cleanly and remains sharp longer than the old form.
In some cases in order to sever the paper with a curved cut we propose to
employ a thin curved steel blade secured to a revolving roller or carrier as is
shown in Sheet 2 of the drawings.
In the said drawings.
Fig. 5 is a front view of this type of severing arrangement.
Fig. 6 is a sectional view of Fig. 5 taken on the line A B.
Fig. 7 represents a blank of paper severed at each end with a circular cut.
Under this part of our invention we employ a cylindrical roller suitably
formed or cut away to receive the thin curved cutter which is clamped in
position by means of a curved plate 7 and set screws. The roller carrying the
thin curved blade is arranged parallel with the drawing rolls and revolves
against a fixed parallel blade m mounted on a supporting bar carried on
adjustable brackets ¹. The paper to be cut is fed forward by suitable rollers
not shown and by the action of the revolving curved knife k against the fixed
blade m the paper is severed at intervals with a curved cut as indicated at o
Fig. 7.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1) In mechanism for cutting or severing sheets or tubes of paper, mounting
the revolving cutting blade on a tapered roller or conical carrier and so as to
act in conjunction with a fixed inclined blade, in the manner, for the purposes,
and substantially as described.
2) In combination, in mechanism for cutting or severing sheets or tubes of
paper, a conical roller , a thin steel cutter i and a fixed inclined blade e, sub-
stantially as described.
3) The improved means for severing sheets or tubes of paper with a curved cut,

page_text: consisting of a cylindrical roller provided with a thin curved steel blade or
cutter and acting in conjunction with a fixed blade, in the manner, and sub-
stantially as herein described and shown in Sheet 2 of the drawings.
Dated this 24th day of October 1899
E. K. DUTTON & Co.,
Chartered Patent Agents, 5, John Dalton Street, Manchester.