IMPROVEMENTS IN THE MANUFACTURE OF PAPER
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
BONSOR CROMPTON, of Farnworth, Bolton, in the County of Lancaster, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by
Her Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Ninth day of April, in the second year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said
Thomas Bonsor Crompton, Her especial licence, full power, sole privilege and
authority, that I, the said Thomas Bonsor Crompton, my exors, adñors, and
assigns, or such others as I, the said Thomas Bonsor Crompton, my exors,
admors, 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 expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF PAPER;" in which said Letters Patent is contained
a proviso that I, the said Thomas Bonsor Crompton, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be inrolled in Her said 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.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Thomas Bonsor Crompton, do hereby declare the nature of my said Invention,

page_text: and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being
had to the Drawing hereunto annexed, and to the figures and letters marked
thereon, that is to say :-
My Invention relates to a mode of obtaining a partial vacuum below a
portion of the moving endless wire cloth on which the pulp is laid in the
making of paper, in order to facilitate the separation of water therefrom. In
making paper by means of what are known as Fourdrinier's 'machines, partial
vacuum has been before resorted to for facilitating the getting away of water
and pressing the pulp by means of the outer atmosphere pressing towards the
vacuum below the moving endless wire cloth employed; but in such cases
very expensive air-pumps have been used for withdrawing air from below the
moving endless wire cloth, and it is well known to machinists that owing to the
change of stroke of the pistons of such air pumps an uniform withdrawing
of air cannot be obtained; hence the pulp passing over the vacuum chamber
receives varying degrees of pressure which tends to make the paper of an
equal thickness; hence it has become desirable in using a partial vacuum below
the moving endless wire cloth, that the vacuum may at all times be maintained
at as uniform a degree as possible, in order that the pressure of the atmosphere
may press on all parts of the paper equally at all times, as it is progressively
made. And my Invention consists in combining revolving fans (similar to
those which are now extensively employed as blowing machines) with such
paper machines as are known as Fourdrinier's machines, that is, where an
endless moving wire cloth is used to receive the pulp, as is well understood.
Figure 1 shows a plan, and Figure 2 a side view of what may be called the
vacuum box or chamber, which is placed just before the couching rollers;
Figure 3 is a side section, and Figure 4 a plan of the description of rotatóry
fan which I employ. At the time, I would observe that the shapes of the
vanes may be varied as well as the numbers of vanes, but I prefer that
whatever be the number, that it should be an odd number. employed. a is
the vacuum box or chamber, which has two sliding ends b, b, capable of being
moved to and from each other in order to their being adjusted to the
width of paper which at the time is being made on the moving wire cloth,
and the upper edges of the vacuum box or chamber and sliding ends are
covered with leather, in order to ensure the wire cloth being as air-tight as
possible. At the upper part of the vacuum box or chamber, 'a series. of wires
(about a quarter of an inch diameter, set about half an inch apart,) are affixed
from end to end of the vacuum box or chamber, which are supported at
intervals, as is shewn at c, c. At one end of the vacuum box or chamber is

page_text: a trunk or pipe d, which is connected to the rotatory fan, and e is a syphon by
which the water received into the box or chamber is drawn off; f is the case
of the revolving fan, and 9 is the fan with five vanes; i is the eduction
way for the air withdrawn from below the pulp on the moving endless wire
cloth. The rotatory fan may be placed in any convenient position in respect
to the machine to which it is applied; but it is desirable to avoid bends of the
trunk or pipe d, and I generally cause the fan to revolve one thousand two
hundred times in a minute, and I usually have a water syphon to indicate
the pressure, and such pressure may be varied by the speed of the fan
employed.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I lay no claim to
any of the parts separately; but what I do claim is, the combining of rotatory
fans with paper machines having moving endless cloths of wire, as above
described.
In witness whereof, I, the said Thomas Bonsor Crompton, have here-
unto set my hand and seal, this Seventh day of October, One thousand