A NEW OR IMPROVED METHOD OF AND APPARATUS FOR WASHING OR CLEANSING " WHILST IN MOTION THE FELTS USED IN MAKING PAPER BY MACHINE
Year: 1870

page_text: LETTERS PATENT to Thomas John Marshall, of Bishopsgate Street
Without, in the City of London, Engineer, for the Invention of "A
NEW OR IMPROVED METHOD OF AND APPARATUS FOR WASHING OR CLEANSING
"
PROVISIONAL SPECIFICATION left by the said Thomas John Marshall
at the Office of the Commissioners of Patents, with his Petition,
on the 2nd December 1870.
I, THOMAS JOHN MARSHALL, of Bishopsgate Street Without, in the
City of London, Engineer, do hereby declare the nature of my said
Invention for "A NEW OR IMPROVED METHOD OF AND APPARATUS FOR WASHING
OR CLEANSING WHILST IN MOTION THE FELTS USED IN MAKING PAPER BY MACHINE,"
to be as follows:-
My Invention relates to the effectual washing or cleansing of the felts
usually known as the "wet press felts," used in the manufacture of paper
by machinery whilst the said felts are at work or in motion.

page_text: My Invention consists in the use of a perforated cylindrical roll or
vacuum cylinder of gun metal, brass, or of other suitable metal. This
roll is mounted on hollow trunnion bearings, and has within it, fitted to
the interior surface in such a manner as to be air-tight thereto, a box or
trough. This box or trough may be of any shape convenient for that
purpose, but by preference I make it in the shape of a segment of a
circle. This box or trough is connected by means of two or more short
metal tubes with another pipe or tube passing through the centre of the
perforated cylindrical roll or vacuum cylinder. One end of this pipe or
tube is connected with another tube leading to a suction pump or pumps
by preference to a set of three barrel pumps. The perforated cylindrical
roll is made to revolve by means of ordinary gear connected with and
driven by other parts of the machine, and is rotated at such a rate that
its periphery travels at the same speed as the revolving felts. I prefer
as the most suitable means that the speed should be regulated by an
expanding pulley driven by a belt. After the revolving continuous or
endless felt carrying the wet paper from the making machine through
the pressing rollers is separated from the paper it will pass a jet tube or
trough of warm or cold water, or through a trough kept supplied with
water in contact with a beater, and then between a pair of rollers, drums,
or reels on its way to the before-named perforated cylindrical roll or
vacuum cylinder, where the cleansing is perfected by means of the action
of the pumps and vacuum box chamber, or trough through the per-
forations of the cylindrical roll, by which means any loose particles or
impurities that may adhere are thoroughly removed from the felt. The
washing or cleansing having been effected the continuous felt passes
on again to receive the paper from the making machine and carry it
through the pressing rollers as before. I also apply a brush or brushes-
extending across the whole width of the felt to assist in freeing the felt
from any particles of pulp or stuff that might otherwise adhere to it.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas John Marshall in the Great Seal Patent
Office on the 2nd June 1871.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of December, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Thomas John Marshall, Her special
licence that I, the said Thomas John Marshall, my executors, adminis-
trators, and assigns, or such others as I, the said Thomas John Marshall,
my executors, administrators, 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
"A NEW OR IMPROVED METHOD OF AND APPARATUS FOR WASHING OR CLEANSING
WHILST IN MOTION THE FELTS USED IN MAKING PAPER BY MACHINE," upon the
condition (amongst others) that I, the said Thomas John Marshall, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, 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 Thomas John Marshall, 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:-
My Invention relates to the effectual washing or cleansing of the felts
usually known as the "wet press felts" used in the manufacture of
paper by machinery whilst the said felts are at work or in motion.
In order that the nature of my said Invention and the means by
which the same is to be effected, may be particularly described and
ascertained, this Specification is accompanied by a Sheet of Drawings,
having figures and letters of reference marked thereupon; the like letter
being used to denote a similar or corresponding part in each Figure.
In these Drawings Figure 1 is a side elevation of the apparatus I
employ; Figure 2 a transverse section of the perforated cylinder herein-
after referred to; and Figure 3 shews position of the said apparatus in
the paper-making machine.

page_text: My Invention consists in the use of a perforated cylindrical roll or
vacuum cylinder a of gun metal, brass, or other suitable metal. This
roll is mounted on hollow trunnion bearings 6, and has within it, fitted
to its interior surface in such a manner as to be air-tight thereto, a box
or trough c. This box or trough c may be of any shape convenient for
that purpose, but by preference I make it in the shape of a segment of a
circle, as shewn in the Drawing. This box or trough c is connected by
means of two or more short metal tubes d with another pipe or tube e
passing through the centre of the perforated cylindrical roll or vacuum
cylinder a. One end of this pipe or tube e is connected with another
tube fleading to a suction pump or pumps, by preference to a set of
three barrel pumps. The perforated cylindrical roll a is made to revolve
by means of ordinary gear connected with and driven by other parts of
the machine, and is rotated at such a rate that its periphery travels at
the same speed as the revolving felts. I prefer as the most suitable
means that the speed should be regulated by an expanding pulley driven
by a belt. After the revolving continuous or endless felt carrying the
wet paper from the making machine through the pressing rollers is
separated from the paper, it will pass a jet tube or trough of warm or
cold water, or through a trough kept, supplied with water by the
pipes h, h. In this jet tube or trough the felt is in contact with a beater,
it then passes between a pair of rollers, drums, or reels i, i,
on its way to
the before-named perforated cylindrical roll or vacuum cylinder where
the cleansing is perfected by means of the action of the pumps and
vacuum box chamber or trough through the perforations of the cylin-
drical roll, by which means any loose particles or impurities that may
adhere are thoroughly removed from the felt. The perforations although
only shown at the places marked k extend throughout the entire circum-
ferential length of the cylinder a. The washing or cleansing having
been effected the continuous felt passes on again to receive the paper
from the making machine, and carry it through the pressing rollers as
before. I also apply a brush or brushes extending across the whole
width of the felt to assist in freeing the felt from any particle of pulp
or stuff that might otherwise adhere to it.
Having now particularly described and ascertained the nature of my
said Invention, and the manner in which the same is to be performed, I
wish it to be clearly understood that what I claim is, the method of
washing or cleansing the continuous felts of paper machines whilst in

page_text: motion by means of the use of apparatus consisting of a revolving
perforated cylindrical vacuum roll with hollow trunnions and an internal
vacuum box or trough connected by means of tubes with pumps, so that
by the action of the said pumps all the particles or impurities that may
adhere to the felt are withdrawn through the perforations in the cylin-
drical roll into the vacuum box or trough, I claim the method and also
the arrangement of apparatus all as described herein in this Specification
or in the accompanying Drawing illustrated.
In witness whereof, I, the said Thomas John Marshall, have here-
unto set my hand and seal, this First day of June, in the year
of our Lord One thousand eight hundred and seventy-one.
THO³. J. MARSHALL. (L.S.)