Improved Couching and Vacuum Box Arrangement for Paper Making Machines.
Year: 1897

page_text: Date of Application, 1st July, 1897
Complete Specification Left, 1st Apr., 1898-Accepted, 4th June, 1898
.I.
PROVISIONAL SPECIFICATION.
Improved Couching and Vacuum Box Arrangement for Paper
Making Machines.
I, ALEXANDER BLACK, of Invergowrie, Forfarshire, Paper Maker, do hereby
declare the nature of this invention to be as follows:-
This invention which relates to paper making machines consists of a couching
and vacuum box arrangement to be applied to the "wires" of such machines and
in which a hollow perforated couch roll is used in driving the wire and has placed
within it a stationary vacuum box or chamber in contact with the inner periphery
of the roll for drawing off the water from the moist pulp.
The objects of this arrangement are (1) To dispense with the usual top and
bottom couch rolls with their jackets, doctor and water spray arrangement. (2) To
relieve the wire of the larger amount of the friction resulting from being drawn
across the surfaces of the ordinary stationary vacuum boxes, thereby increasing
the life of the wires, and decreasing the amount of power required to drive the
paper making machine. (3) To relieve the paper of the crushing and thinning
effect of the usual top couching roll, thereby increasing the "bulking" of the
paper, and greatly decreasing the marking on the under side of the paper, caused
by the usual top couch roll crushing or pressing the moist pulp into the meshes of
the wire. (4) To relieve the wire of the crushing and bending action due to the
top couch rolí.
In order to accomplish the objects in view I introduce a hollow perforated roll
made of any suitable material at the delivery end of the paper making machine.
This roll takes the place of the usual bottom couch roll in driving the wire, but
instead of being set at a considerable distance below the top surface. of the wire,
it is preferably placed so that the wire runs practically in a straight line
from the top surface of the perforated roll to the top surface of the
usual breast roll, though the wire may be level or dip towards the
breast roll in the usual way. A hollow trunnion is fixed in a suitable manner to
each end of the perforated roll or shell, these trunnions being supported by, and
running in any of the usual well known bearings secured to the framing of the
machine. Through the trunnions supporting, the perforated roll I introduce an
oblong vacuum chamber made of any suitable material and designed to suit the
required internal diameter of the perforated roll against which it bears. This
chamber consists of two bottoms (a false one perforated with three or more-holes,
and the true or outside bottom) two sides, and, sliding ends adjustable to suit the
width of paper being made on the wire. The top or open side of this vacuum
chamber is held against the interior surface of the perforated roll, so that the part
of the roll which for the time being covers the open side in the vacuum chamber
forms the perforated lid of a box which the vacuum chamber practically is.
In order to prevent the entrance of air into the interior of the vacuum chamber
(except what is drawn through the meshes of the wire and perforations in the roll

page_text: with the water from the paper pulp travelling with the wire) the chamber is placed
at such an angle relatively to a vertical line passing through the centres of the trun-
nions, that the wire with the wet pulp entirely covers the top or open side of the
vacuum chamber.
The vacuum chamber is secured to the machine framing by a suitable arrange-
ment of adjustable holding screws, which, while permitting the perforated roll
to revolve easily in the trunnion bearings retain the vacuum chamber in a fixed
position, and prevent it from revolving with the perforated roll.
The vacuum chamber may however be retained in position by weighted or other
levers, which permit of the easy adjustment of the vacuum chamber relatively to
the interior surface of the perforated roll. The space between the perforated
or false bottom, and the true or solid bottom is connected to a vacuum pump, or
set of vacuum pumps, or other exhausters.
The action of the improved couching and vacuum chamber arrangement is as
follows: As the perforated roll with the wire carrying the moist pulp revolves,
the vacuum produced in the chamber by the exhauster extracts the necessary
amount of water so as to permit of the paper being pressed in the usual way after
leaving the wire. I may retain the usual first vacuum box with the deckle
arrangement, but my couching and vacuum box apparatus accomplishes the work
usually performed by the couch rolls and vacuum box or boxes at present placed
after the first vacuum box; or I may use a perforated roll and vacuum chamber
constructed as above described in lieu of the first vacuum box and drive the one
roll from the other so as to still further lessen the friction on the wire.
Dated this 30th day of June 1897.
WALLACE FAIRWEATHER;
Chartered Patent Agents, 62, Saint Vincent Street, Glasgow,
Of the Firm of Cruikshank & Fairweather,
Agent for the Applicant.
Improved Couching and Vacuum Box Arrangement for Paper
Making Machines.
I, ALEXANDER BLACK, of Invergowrie, Forfarshire, Paper Maker, do hereby-
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
This invention which relates to paper making machines consists of a couching
and vacuum box arrangement to be applied to the "wires" of such machines and
in which a hollow perforated couch roll is used in driving the wire and has placed
within it a stationary vacuum box or chamber in contact with the inner periphery
of the roll for drawing off the water from the moist pulp.
The objects of this arrangement are (1) To dispense with the usual top and
bottom couch rolls with their jackets, doctor and water spray arrangement. (2) To
relieve the wire of the larger amount of the friction resulting from being drawn
across the surfaces of the ordinary stationary vacuum boxes, thereby increasing the
life of the wires, and decreasing the amount of power required to drive the paper
making machine. (3) To relieve the paper of the crushing and thinning effect
of the usual top couching roll, thereby increasing the "bulking" of the paper,
and greatly decreasing the marking on the under side of the paper, caused by the
usual top couch roll crushing or pressing the moist pulp into the meshes of the

page_text: wire.
couch roll.
(4) To relieve the wire of the crushing and bending action due to the top
The invention is illustrated by the accompanying drawings, Figure 1 being a
longitudinal elevation partly in section, and Figure 2 a transverse section of the
improved combined couch roll and vacuum box, shewing one method of carrying
the vacuum box within the couch roll. Fig. 3 is a longitudinal elevation of part
of a paper making machine shewing the position of the couch roll and the method
of carrying the vacuum box therein.
In order to accomplish the objects of the invention I introduce a hollow per-
forated roll A made of any suitable material at the delivery end of the paper
making machine B. This roll takes the place of the usual bottom couch roll in
driving the wire C, but instead of being set at a considerable distance below the top
surface of the wire, it is preferably placed so that the wire C runs practically in
a straight line from the top surface of the perforated roll A to the top surface of
the usual breast roll, though the wire may be level or dip towards the breast roll
in the usual way. A hollow trunnion A¹ is fixed in a suitable manner to each end
of the perforated roll or shell, these trunnions being supported by, and running in
any of the usual well known bearings 1), Figure 3, secured to the framing of the
machine B. Through the trunnions A' supporting the perforated roll A, I intro-
duce an oblong vacuum chamber E made of any suitable material and designed
to suit the required internal diameter of the perforated roll A against which it
bears. This chamber may consist of two bottoms (a false one perforated with
three or more holes, and the true or outside bottom), or, as shewn, of a single
bottom E¹, two slides E2, and sliding ends E3, adjustable to suit the width of paper
being made on the wire. The top or open side of this vacuum chamber E is held
against the interior surface of the perforated roll A, so that the part of the roll
which for the time being covers the open side in the vacuum chamber forms the
perforated lid of a box which the vacuum chamber E practically is.
In order to prevent the entrance of air into the interior of the vacuum chamber E
(except what is drawn through the meshes of the wire C and perforations in the
roll A with the water from the paper pulp travelling with the wire) the chamber E
is placed at such an angle relatively to a vertical line passing through the centres
of the trunnions A', that the wire C with the wet pulp entirely covers the top or
open side of the vacuum chamber E.
The vacuum chamber E is preferably secured to the machine framing by a suit-
able arrangement of adjustable holding screws F, as shewn at Figure 2, which,
while permitting the perforated roll A to revolve easily in the trunnion bearings
retain the vacuum chamber E in a fixed position, and prevent it from revolving
with the perforated roll A.
The vacuum chamber E may however be retained in position by weighted or
other levers G, as shewn at Figure 3, which permit of the easy adjustment of the
vacuum chamber E relatively to the interior surface of the perforated roll A.
The space between the perforated or false bottom, when a double bottom is
employed, and the true or solid bottom is connected to a vacuum pump, or set of
vacuum pumps, or other exhausters, and when a single bottom only is employed the
pipe connection from the vacuum pump is led through the bottom into the
chamber E.
The action of the improved couching and vacuum chamber arrangement is as
follows: As the perforated roll A with the wire C carrying the moist pulp
revolves, the vacuum produced in the chamber E by the exhauster extracts the
necessary amount of water so as to permit of the paper being pressed in the usual
way after leaving the wire C. I may retain the usual first vacuum box with the
deckle arrangement, but my couching, and vacuum box apparatus accomplishes
the work usually performed by the couch_rolls and vacuum box or boxes at present
placed after the first vacuum box; or I may use a perforated roll and vacuum
chamber constructed as above described in lieu of the first vacuum box and drive
the one roll from the other so as to still further lessen the friction on the wire.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
1. In paper making machines the combined couching and vacuum box arrange-
ment hereinbefore described and illustrated by the accompanying drawings.
2. In a paper making machine the combination with a perforated roll carrying
the "wire" of a stationary vacuum box or chamber placed within and maintained
in contact with the perforated roll substantially as described.
Dated this 31st day of March 1898.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents, 62, Saint Vincent Street, Glasgow,
Agent for the Applicant.