IMPROVEMENTS IN MACHINERY APPLICABLE TO THE MANUFACTURE OF PAPER
Year: 1851

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
LIGHTFOOT, of Jarrow Paper Mills, South Shields, in the County of Durham,
Paper Manufacturer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Sixteenth day of October, in the fifteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Thomas Lightfoot, Her especial license, full power, sole privilege and autho-
rity, that I, the said Thomas Lightfoot, my exors, adiñiors, and assigns, and
such others as I, the said Thomas Lightfoot, my exors, adñors, or assigns,
should at any time agree with, and no others, from time to time and at all
times during the term of years therein mentioned, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of
Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN MACHINERY APPLICABLE
TO THE MANUFACTURE OF PAPER;" in which said Letters Patent is contained a
proviso obliging me, the said Thomas Lightfoot, by an instrument in writing
under my hand and seal, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, and to
cause the same to be enrolled in Her Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said in
part recited Letters Patent, as in and by the same, reference being thereunto
had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Thomas Lightfoot, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say):-
My Improvements in Machinery applicable to the Manufacture of Paper
relate to the rag engine, or that part of the machinery in which the rags are
reduced to a state of pulp ready to be made into paper. The ordinary rag
engine in general use merely consists of an oblong cistern divided for about
two thirds of its length by a partition running up the middle. At one side of
this partition is mounted a "roll," which has a series of knives placed round
its circumference. This "roll "is made to revolve rapidly upon or above a
a series of knives which are secured underneath, and are called the "plate."
The cistern being filled with water and rags, and motion being communicated
to the roll, the rags are drawn underneath it and over the plate; it then draws
them over the raised part behind it called the "back-fall" or "weir." By
falling over the "weir" the pulp or rags acquire sufficient momentum to
cause them to travel round the end of the partition until they return to the
roll, which again draws them in, and carries them over the plate and "backfall,"
as before, until they are torn and cut into fibre.
One of the improvements which forms part of the present Invention consists
in the introduction of a second roll placed behind the first, as shewn in the
accompanying Drawings, which represent a rag engine constructed according
to my present improvements. This second roll is made to revolve more
rapidly than the first, and from its position the rags are thrown upon it by the
first roll in an opened-out condition, whereby it acts upon every fibre, whereas
in the ordinary engine they go in before the roll in large wedge-like masses,
and half the power is consequently lost. Both rolls are mounted in adjustable
bearings, so that they may be raised from or lowered on to the plates at
pleasure by means of levers and screws, as in the ordinary engine. This
improved arrangement, and the construction and operation of the several parts,
will be best understood by referring to the accompanying Drawings, in which
Fig. 1 represents a plan view of my improved rag engine; Fig. 2 is a longi-
tudinal vertical section of the same; Fig. 3 is a transverse vertical section;
and Fig. 4 is a section taken in the line 1, 2, of Fig. 1. a and a are the
rolls, and are the backfalls or weirs behind the rolls. Beneath the rolls
are the plates c, c¹, which consist of a number of vertical knives or cutters
secured in a recess below the rolls.

page_text: An entirely new system of washing apparatus is adapted to the engine, and
forms the second part of my Invention. It will be seen by referring to Fig. 3,
that the partition e, technically called the "midfeather," is made hollow, and is
furnished with openings which are covered with woven wire on the side oppo-
site the rolls. The side of the engine also has recesses f, f, formed therein,
and covered in a similar manner with wire gauze or other suitable perforated
material, and along or across the bottom of the engine hollow spaces d, d,
(see Fig. 4) are made, and covered level with the bottom of the engine with
perforated plates or bars. Through these wired facings and perforated plates
the dirty water passes into the recesses and hollows d, e, and f¹, and from
thence into two or more pipes h and i, large enough to carry it to a receptacle
9, in which a series of slides h¹, i, are adapted to the ends of the pipes,
and are worked by an excentric or crank l, or otherwise connected in some
convenient manner to and worked by a prime mover, so that the egress of the
water from the pipes shall not be continuous but alternating; in other words,
by the rising and falling of the slides h¹ and ¹ at each end of the lever k, the
flow of the water will be stopped for a certain period of time, say, one or two
seconds, in first one and then the other of the pipes, and then allowed to flow
for the same length of time, and so on, alternately. The stoppage of the flow
in the pipes causes a cessation of suction through the wire and perforated
plates; and if any fibres of rag have been drawn into the interstices of the
wire or perforations of the plates, they are then drawn out and carried forward
in the engine by the flow of water and rag or pulp over them, and by this
means the straining surfaces or perforated plates are kept clean. In order
more effectually to avoid a strong suction through the wires when the fibre
shall have become short, the slides above named are made to work in the
cistern 9 into which the water flows, and from which it has egress by two
passages, one at the bottom of the cistern, to be used in the first part of the
washing process, and the other at the top, a little below the level of the pulp
in the engine, to be used when the fibre shall have become short. During
the washing operation a stream of clear water continually flows into the engine
from a pipe p placed above the fall, between the rolls, and parallel with them,
baving a longitudinal slit or opening along its undermost side about two feet
long and an eighth of an inch wide, so that the water from it may fall upon
the rags before they pass under the second roll. Previous to the rags being
placed in the engine just described, it will be found necessary to wash and
boil them, and open the fibres of the rags. The apparatus I employ for this
purpose consists of a cylinder with perforated sides which is mounted and

page_text: made to revolve in a water-tight cistern. In the sides of the cylinder, and
projecting inwards, are several rows of spikes from six to twelve inches long.
The shaft or spindle on which the cylinder is mounted is made hollow, and is
also furnished with spikes. Into this cylinder water and steam are admitted
through the hollow shaft or spindle, which is perforated with holes for the
purpose. In the side of the cylinder is a door which, being furnished with
hinges, may be opened and closed when desired, and in the surrounding
cistern another door, so made as to be water-tight when closed, and so placed
that the door of the cylinder can be brought opposite to it to be opened. The
ends of the hollow shaft of the cylinder, where they pass through the surround-
ing cistern, are mounted in packing boxes for the purpose of keeping the cistern
water-tight. The cylinder being filled with rags is put in motion by spur
wheels or otherwise, and water being allowed to pass in, the rags are agitated
and torn by the spikes, and washed at the same time. The dirty water is
then allowed to pass out at the bottom of the cistern, and the process being
continued as long as is deemed necessary, the flow of the water is stopped.
A portion of alkali may then be placed in the cylinder, and steam allowed to
pass in to boil the rags.
Having now described my Invention, and the best means with which I am
acquainted for carrying the same into effect, I would observe, in conclusion,
that I do not mean or intend to confine myself rigidly to the precise construc-
tion and arrangement of parts herein shewn and described, as they may,
perhaps, be varied without departing from the nature and object of my
improvements. But that which I consider to be new, and therefore wish to
claim as the Invention secured to me by the herein-before in part recited
Letters Patent, is the employment of two rolls in the rag engine, one of which
rolls is driven at a speed superior to the other.
I also claim making the sides and bottom of the vat and midfeather hollow;
and also the method herein shewn, or any modification thereof, whereby the
dirty water may be carried off from the rags or pulp, and the flow of the dirty
water from the engine may be periodically interrupted, so as to prevent the
pulp from being sucked through the straining surfaces, as above described.
In witness whereof, I, the said Thomas Lightfoot, have hereunto set my
hand and seal, this Thirteenth day of April, in the year of our Lord
One thousand eight hundred and fifty-two.
THOMAS (L.s.) LIGHTFOOT.

page_text: AND BE IT REMEMBERED, that on the Thirteenth day of April, in the
year of our Lord 1852, the aforesaid Thomas Lightfoot came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
5 written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Enrolled the Sixteenth day of April, in the year of our Lord One thou-
sand eight hundred and fifty-two.