IMPROVEMENTS IN PRINTING MACHINES
Year: 1869

page_text: LETTERS PATENT to Aaron Bradshaw, of Accrington, in the County
of Lancaster, for the Invention of "IMPROVEMENTS IN PRINTING
MACHINES."
Sealed the 28th June 1870, and dated the 31st December 1869.
PROVISIONAL SPECIFICATION left by the said Aaron Bradshaw at the
Office of the Commissioners of Patents, with his Petition, on the
31st December 1869.
I, AARON BRADSHAW, of Accrington, in the County of Lancaster, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
PRINTING MACHINES," to be as follows:-
This Invention consists in improved arrangements of machinery or
apparatus for the purpose of employing hydraulic power to give the
necessary pressure to the rollers, and also to obtain for each or any of
the rollers an intermittent nip when required.

page_text: The two bearings of each roller are connected to rams in cylinders
with water-tight packing, as in the hydraulic press, the cylinders com-
municating by pipes to a water chamber connected with one or more
force pumps and the chamber provided with a safety and regulating
valve. The force pumps are similar to those used for hydraulic presses,
and when with great pressure they force water into the water chamber
and cylinders the rams press the rollers against the central cylinder with
a force corresponding with the pressure of the water and the diameters
of the rams. For giving intermittent nips to any of the rollers the water
is supplied to and cut off from the corresponding cylinders alternately,
the roller when the water is off being brought back to take off the nip
by weights or springs, and when the nip is to be again given to the
roller the cut-off is closed and the supply put on, the movements for
working the cocks or valves being regulated by catches or projections on
a revolving part of the machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Aaron Bradshaw in the Great Seal Patent Office on
the 29th June 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, AARON
BRADSHAW, of Accrington, in the County of Lancaster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirty-first day of December, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Aaron Bradshaw, Her special license that
I, the said Aaron Bradshaw, my executors, administrators, and assigns,
or such others as I, the said Aaron Bradshaw, my executors, adminis-
trators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN PRINTING MACHINES," upon the condition, amongst others, that
I, the said Aaron Bradshaw, by an instrument in writing under my

page_text: hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said Aaron Bradshaw, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Figure on the
accompanying Sheet of Drawings, and to the letters of reference marked
thereon (that is to say) :-
This Invention consists in improved arrangements of machinery or
apparatus for the purpose of employing hydraulic power to give the
necessary pressure to the rollers, and also to obtain for each or any of
the rollers an intermittent nip when required.
The two bearings of each roller are connected to cylinders on rams or
to rams in cylinders with water-tight packing, the cylinders com-
municating, by pipes. to.a water or other liquid chamber or accumulator
connected with one or more force pumps, and the accumulator is
provided with regulating valves between it and the cylinders, and also
with a safety valve. The force pumps are similar to those used for
hydraulic presses, and when they force water or other liquid into
the accumulator and through the regulating valves into the cylinders
the rollers are pressed against the central cylinder with a force corre--
sponding with the pressure of the liquid and the diameters of the.
rams. For giving intermittent nips to any of the rollers the liquid'
is supplied to and let off from the corresponding cylinders alternately,.
the roller being brought back by weights or springs when the liquid:
is let off, and when the nip is to be again given the let-off is closed
and the supply put on, the movements for working the regulating
valves being obtained by catches or projections on a revolving part
of the machine.
The Figure on the accompanying Sheet of Drawings is a side view.
with part in section shewing the application of one arrangement of my
improvements to two of the rollers of a four-colour printing machine;.
a representing part of the framework; b, the central cylinder; c, the-

page_text: rollers; and d, the endless web. The shafts e of the rollers work in
bearings ffixed or cast to the blocks g fitted in girders h forming part of
the framework, and in each block there is a circular hole i used as a
hydraulic cylinder. In the hole is placed the ram k packed with
hydraulic packing 1, and in contact with the outer end of the ram there
is an adjusting screw m, connected by a nut with a weighted lever or
other self-adjusting arrangement. To each block g is held a plate m¹ by
bolts n, and between the plate and the outer end of the ram there is a
spiral or other spring o adjusted by nuts p, and to each block is attached
a pipe q kept tight by the gland r. The screw m and weighted lever
are so adjusted that the roller is about a quarter of an inch from the
endless web when the pressure from the accumulator is off, and the
weight of the lever is held in its lowest position; but when com-
munication with the accumulator is established with the cylinder by
means of the regulating valve the block rises and the ram descends, the
block placing the roller against the endless web and compressing the
spring o, the roller remaining against the endless web as long as the
communication with the accumulator is maintained, the weighted lever
being required to adjust itself to any irregularities that may exist in the
central cylinder or endless web as in ordinary printing, but the moment
the pressure is removed from the cylinder by the regulating valve the
spring o brings back the block, and removes the roller from the endless
web, and it is evident that as any of the rollers can be placed in its
working position and taken off as often as the water or other liquid is
forced in and let off the bydraulic cylinder intermittent nips can be
obtained as required. When desired the cylinders and rams may be
reversed, the bearings of the rollers being cast or fixed to the rams, and
the springs adapted to suit; but I prefer the arrangement before
described, as greater steadiness is given to the rollers. In some cases
the weighted levers are dispensed with, and the block g is set to the
required distance from the central cylinder 6 by means of a screw, the
put of which rests on india-rubber blocks in a metal chamber, and when
these are used I place the hydraulic apparatus between the india-rubber
blocks and the roller,
L

page_text: of hydraulic pressure to obtain constant or intermittent nips, as herein
described and illustrated on the accompanying Sheet of Drawings.
In witness whereof, I, the said Aaron Bradshaw, have hereunto
set my hand and seal, this Twenty-seventh day of June, in the
year of our Lord One thousand eight hundred and seventy.
AARON BRADSHAW. (L.s.)