IMPROVEMENTS IN MACHINERY FOR CUTTING PAPER
Year: 1883

page_text: LETTERS PATENT to Thomas Galloway Dawson and Jeremiah Dawson of
Otley in the county of York, Printers Engineers. for an Invention of
IMPROVEMENTS IN MACHINERY FOR CUTTING PAPER
PROVISIONAL SPECIFICATION left by the said Thomas Galloway Dawson
and Jeremiah Dawson at the Office of the Commissioners of Patents on the
6th July 1883.
THOMAS GALLOWAY DAWSON and Jeremiah Dawson of Otley in the County of
York, Printers Engineers IMPROVEMENTS IN MACHINERY FOR CUTTING PAPER
Our invention relates to what is known as Guillotine paper cutting machines,
and has for its object an improved clamping apparatus whereby any thickness of
paper, or other material is held whilst being cut and a considerable amount of the
power exerted for clamping and raising the knife bar is partly utilized for the
cutting of the paper
We accomplish the above by mounting to a cross bar of the machine two double
sectors gearing into each other at the centre, whilst the outer portions of each
sector gear into racks one on each side of the machine and secured to each end
of the clamping bar.
To a stud on one of the double sectors we connect a rod the other end of which
is mounted to a right angled lever the long end of which is lifted by a bowl on a
crank fixed on the main shaft of the machine: this right angled lever is carried on
a stud fixed about midway between the centre and periphery of a circular plate
which we term a retarding plate.
This plate is held down to a stop by spiral springs which are compressed and act
through levers upon the cutting bar in the direction of the cut thus assisting the
knife to perform its work. When the machine is started the clamping bar is
brought down by the crank on the main shaft until the pressure on the paper
overcomes the power of the springs on the retarding plate when the plate and
springs move around at the same speed as the knife bar and the pressure is
maintained until the knife has cut through and returned above the paper.

page_text: :
.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Galloway Dawson and Jeremiah Dawson in the Patent Office
on the 5th January 1884.
THOMAS GALLOWAY DAWSON and JEREMIAH DAWSON of Otley in the County
of York. Printers Engineers. IMPROVEMENTS IN MACHINERY FOR CUTTING PAPER.
Our invention relates to what is known as Guillotine paper cutting machines,
and has for its object an improved clamping apparatus whereby any thickness of
paper or other material is held whilst being cut, and to utilize a considerable
amount of the power exerted for clamping for the cutting of the paper.
We accomplish the above by mounting to a cross bar of the machine, two double
sectors gearing into each other at the centre, whilst the outer portions of each sector
gear into racks one on each side of the machine secured to each end of the
clamping bar.
To a stud on one of the double sectors we connect a rod, the other end of which
is carried by a stud fixed to an angular lever, the long end of which is lifted by a
bowl on a crank fixed to the main shaft of the machine; this angular lever is
carried on a stud fixed about midway' between the centre and periphery of a
circular plate which we term a retarding plate. This plate is held down to a
stop by spiral springs which are compressed and act through levers upon the
cutting bar in the direction of the cut, thus preventing the jarring of the knife and
assisting it to perform its work.
.
When the machine is started, the clamping bar is brought down by the action of
the before mentioned crank, until the pressure on the paper or other material
overcomes the power of the springs in connection with the retarding plate; then
the plate will move round in accordance with the thickness of the paper to be cut
without further compressing the said springs, and after the cutting has taken place,
the retarding plate will move back to its original position; the springs pressing a
lever against the knife bar in the direction of the cut, thereby assisting the knife
to perform its work.
The pressure of the clamping bar upon the paper is maintained until the knife
has cut through and returned above the paper, when it is relieved by the action of
tlie crank on the main shaft.
In order that our invention may be more clearly understood, we have hereunto
'appended drawings in which Figure 1 represents such portions of a Guillotine
cutting machine as are required to explain our invention, and Figure 2 is an end
'view thereof, similar letters indicate similar parts.
The machine is driven and motion communicated to the main shaft A in the
'usual manner. To the cross bar B secured to each end frame C, we mount upon
studs two double sectors D and D1 gearing with each other at the centre, and at
the outside with the racks E and E¹, one of which is secured to each end of the
clamping bar F. The clamping bar F can be brought down by hand by means of
lever F to indicate the line of cut.
The sector D and the angular lever G are connected together by means of rod H,
and the lever G is carried by a stud J secured to the retarding plate L, which is
'supported by a bracket M secured to the end frame of apparatus.
When the machine is set in motion the bowl B' on revolving crank C¹, raises the
long end of lever G and thereby moves the short end at G' and the connecting
rod H in the direction of the arrow, causing the sectors D and D¹ to turn on their
centres, and the racks E. and E. and clamping plate F to descend and firmly secure
any material that may be placed between the table T and the said bar. When.
the material has been pressed to such a degree as to overcome the pressure of

page_text: the spiral springs S, which are compressed between projections on the retarding
plate and levers N, the retarding plate will then move in the bracket M and
maintain the pressure upon the said springs, until the knife cuts through and
returns above the paper.
1
By the springs being compressed in the manner described before the knife begins
to cut, the surplus power exerted in clamping the material is absorbed by the
springs S and utilized when cutting the paper. This is effected by the compressed
springs S acting upon the levers N mounted on a short shaft, and which cause the
long end of one of the levers at N¹ to press against the bowl B³ mounted on a stud
passing through the jaw of knife bar K, and thereby assisting the ordinary
oscillating link through the connecting rod R to move the knife in the direction of
the cut.
Having thus described our invention and the manner in which the same is to be
performed, we have to state that what we claim as our invention is :-
The arrangement and combination of the retarding plate, and spiral springs with
the levers N substantially in the manner and for the purpose as herein before.
described, and as illustrated by the accompanying drawings.
The arrangement and combination of the crank C¹, lever G, connecting rod H
and double sectors with the racks and clamping bar substantially in the manner
and for the purpose as hereinbefore described and as illustrated by the
accompanying drawings.
In witness whereof I the said Thomas Galloway Dawson for and on behalf of
myself and the said Jeremiah Dawson have hereunto set my hand and seal this
third day of January in the year of our Lord one thousand eight hundred and
eighty four.
THOS G DAWSON (L.S.)