Improvements in Paper Making Machines.
Year: 1892

page_text: Date of Application, 17th June, 1892
Complete Specification Left, 16th Mar., 1893-Accepted, 2nd June, 1893
PROVISIONAL SPECIFICATION.
Improvements in Paper Making Machines.
I, ROBERT WIGHTON MONCRIEFF General Manager and Engineer for The
Sparre Patents Company Limited of 53 Sackville Street, Manchester, do hereby.
declare the nature of this invention to be as follows:-
This invention relates to paper making machines and has special reference to
machines of the kind in which separate laid or wove moulds are employed.
The improvements chiefly consist of a special construction or make of mould and
of arrangements or means whereby an air-tight sealed chamber communicating only
with exhaust or suction pipes is formed.
In carrying out my invention I make the frames and cross bars of the moulds
deep enough to clear the under edge of the travelling links or frames by which
they are carried, and exactly level at bottom so as to bear closely upon an endless
belt below. This belt which may be of india rubber or of other suitable material
passes round two light rollers that are free to turn on axes which are at right
angles to the line of travel of the moulds, so that as the moulds travel onwards the
close contact of the cross bars as well as of the outer frame of the moulds, causes
the rollers to rotate and the belt to travel. A constant joint is thus formed over a
considerable area, the extent of which will depend upon the length of the belt.
This joint constitutes one side of the air-tight scaled chamber.
The rollers revolve in a "suction box" kept constantly filled with water, the
surface of which constitutes the bottom of the sealed chamber, the upper part of
the rollers and of the belt being above the water level. To the upper edge of that
side of the box over which the moulds travel subsequently to leaving the endless
belt I fasten strips of india rubber or other suitable material upon which the mould
frames and cross bars successively press in passing; air is thus excluded at this
side which constitutes a second side of the air tight sealed chamber. Or instead of
the strips just described I can form this side of the sealed chamber by another
endless belt and rollers like those already described. The two ends of the sealed
chamber, that is to say the parts between the surface of the water and the bottom
of the mould ends can be sealed by strips of rubber-faced brass or other suitable
material kept pressed by springs up to the mould ends, the top of the strips just
clearing the bottom of the links that carry the moulds. These strips and springs
can conveniently be supported on blocks fastened to the suction box. The pulp on
the surface of the moulds between the deckle straps forms the top of the sealed
chamber as far as it extends, the surface under the deckle straps and any part
which may project beyond these I cover with sheet metal, so that air cannot be
drawn in at these parts.
In the air tight sealed chamber are the open ends of three or other suitable
number of suction pipes leading to the ordinary vacuum pumps. The ends of the
pipes are placed as far as possible above the surface of the water in the suction box
without their coming into contact with the cross bars of the moulds.
It will be readily understood that when communication is opened with the pumps
a vacuum will be created in the sealed chamber and that the moisture in the pulp
lying on the surface of the moulds will consequently be extracted as the moulds
pass over the chamber. The moulds then pass forward under the couching roll.
Instead of the endless belt and rollers hereinbefore described I can employ a
non-travelling bed of india rubber or other suitable material upon which the cross
bars bear as they travel above the water box, but this modification is not to be
recommended because of the additional friction that would be caused.
According to another arrangement I enclose a box in the under surface of each

page_text: mould with zinc, copper or other suitable material, leaving an opening in the middle
around which I hang an edging or hood of india rubber or other suitable flexible
material which projects a few inches below the mould. All the joints of the zinc
covering and hood should be air-tight. Below the centre of the series of moulds is
a longitudinal suction or water box to which are connected at intervals suction
pipes leading to a vacuum pump or pumps, the ends of these pipes projecting
slightly above the water in the box.
As the moulds travel along the machine in succession the hood of each yields so
as to pass over the end of and into the suction box, the said end being preferably
rounded; the hood next yields as its leading edge passes over the first suction pipe,
an inclined plane facilitating this movement. Immediately the leading edge of the
nood has passed over the suction pipe the said edge drops into the water which
thus forms an air-tight joint or seal around the hood; consequently the vacuum
pumps exhaust the air from below the mould as it passes over the suction pipe, and
the moisture is therefore extracted from the pulp on the surface of the mould. The
process repeated as the mould passes over the next suction pipe and over as many
more as may be required.
Instead of enclosing or boxing in the under surface of the moulds as above
described, the india rubber or other flexible material may be hung round the edges
of the moulds, the width of the suction or water box being proportionately increased
and a greater number of suction pipes being employed in the width of the suction
or water box; the moisture is thus extracted more quickly and uniformly.
Dated this 17th day of June 1892
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.
COMPLETE SPECIFICATION.
Improvements in Paper Making Machines.
1, ROBERT WIGHTON MONCRIEFF General Manager and Engineer for The
Sparre Patents Company Limited, of 53 Sackville Street, Manchester, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
-
This invention relates to paper making machines and has reference more
particularly to machines of the kind in which separate laid or wove moulds are
employed.
The improvements chiefly consist of a special construction or make of mould
and of an arrangement or means whereby an air-tight sealed chamber communicating
only with exhaust or suction pipes is formed.
In carrying out my invention I make the frames and cross bars of the moulds
deep enough to clear the bottom of the links or frames by which they are carried
and exactly level at bottom so as to bear closely upon an endless belt below.
This belt which may be of india rubber or other suitable material passes round
two light rollers that are free to turn on axes which are at right angles to the line
of travel of the moulds, so that as the moulds travel onwards the close contact of
the cross bars as well as of the outer frame of the moulds causes the rollers to
rotate and the belt to travel. A constant joint is thus formed over a considerable
area, the extent of which will depend upon the length of the belt. This joint
constitutes one side of the air-tight sealed chamber.
The rollers revolve in a "suction box" kept constantly supplied with water, the
surface of which constitutes the bottom of the sealed chamber, the upper part of
the rollers and of the belt being above the water level. To the upper edge of that
side of the box over which the moulds travel subsequently to leaving the endless
belt I fasten strips of india rubber, or other suitable material upon which the
mould frames and cross bars successively press in passing; air is thus excluded at

page_text: the side which constitutes a second side of the air-tight sealed chamber. Or instead
of the strips just described I can form this side of the scaled chamber by another
endless belt and rollers like those already described and I prefer this modification.
The two ends of the sealed chamber, that is to say the parts between the surface
of the water and the bottom of the mould ends can be sealed by strips of rubber-
faced brass or other suitable material kept pressed by springs up to the mould ends,
the top of the strips just clearing the bottom of the links that carry the moulds.
These strips and springs can conveniently be supported on blocks fastened to the
suction box. The pulp on the surface of the moulds between the deckle straps
partly forms the top of the sealed chamber as far as it extends; the under side
of the deckle straps themselves constitutes the remainder of the top of the sealed
chamber.
In the air-tight sealed chamber are the open ends of three or other suitable
number of suction pipes leading to the ordinary vacuum pumps. The ends of the
pipes are placed as far as possible above the surface of the water in the suction
box without their coming into contact with the cross bars of the moulds.
It will be readily understood that when communication is opened with the pumps
a vacuum will be created in the sealed chamber, and that the moisture in the pulp
lying on the surface of the moulds will consequently be extracted as the moulds
pass over the chamber. The moulds then pass forward under the couching roll.
The arrangement or means above described whereby an air-tight sealed chamber
communicating only with exhaust or suction pipes is formed is applicable not only
to machines having separate laid or wove moulds, but also to machines such as
those of the Fourdrinier type in which an endless wire web is employed.
Figure 1 of the accompanying drawings is a section taken longitudinally on the
line 1-1 of Figure 2 (the suction pipes being in elevation) of a portion of a paper
making machine constructed with separate moulds and having a suction box,
suction pipes and air-tight or sealed chambers arranged in accordance with the
preferred form of this part of my invention.
Figure 2 is a section on the line 2-2 of Figure 1.
Figure 3 is a plan of the suction box and of the devices fitted therein, parts of
the end frames of the mould being also seen.
Figure 4 is a diagrammatic partial side elevation on a smaller scale of the paper
making machine and illustrating the general arrangement of the machine, and the
position of the suction box.
Figure 5 is a fragmentary section on the same line as Figure 1, illustrating the
modification in which one side of the sealed chamber is formed by strips of india
rubber on the upper edge of the suction box instead of by another endless belt and
rollers.
Figure 6 is a longitudinal section the same as Figure 1, but illustrating the
application of my invention to an endless wire web machine.
Referring first to the machine illustrated by Figures 1 to 4, each mould consists
of the surface a of "laid" or woven wire carried and supported by side frames bb,
end frames c c and cross bars d d. The side frames & bare secured, together with
interposed metal strips e e, to bars ff placed transversely to the line of travel.
The strips e e extend up to the level of the mould surface a and deckle wires g g
are soldered or otherwise connected thereto. The use of these deckle wires in the
manner indicated does not form part of the present invention; it is embodied in an
application for Patent numbered 23732 of 1892. The bars ff to which the side
frames of each mould are secured extend beyond the said side frames and are
connected by hinges h h to the corresponding bars ff of the adjoining moulds to
enable the moulds to travel round the cuds of the main framing of the machine as
seen in Figure 4. The two bars ff of each mould are connected at their ends to
two bars placed at right angles thereto, and the four bars ffff' thus
connected constitute a travelling link or frame by which the corresponding mould
is carried.

page_text: The bars are formed with racks ii with which gear toothed wheels one of
which is shown at j Figure 4, these toothed wheels being driven by motion trans-
mitted from any suitable prime mover. They impart a regular onward movement
to the endless chain of moulds, the racks on the bars f¹f of the moulds coming
successively into gear with said wheels. There are rollers f2f2 on the frames f¹¹
to run in guides f³ ³ on the main framing of the machine. k, Figure 4, is the pulp
box from which pulp flows in a uniform stream or shect upon the moulds as they
successively pass under it. 11 are the deckle straps passing round guide rollers as
usual. All the parts above referred to in the description of the drawings are of
known construction except that the deckle wires g g are new and that for the
purpose of my invention the side frames bb, end frames c c and cross bars d d of
the moulds instead of being made as heretofore somewhat less deep than the
bars ffff are made deep enough to come below the level of the under edge
of these bars, and the said frames b b and c c and said cross bars d d must be exactly
level at bottom, which has not hitherto necessarily been the case.
m is a suction box situated below the line of travel of the moulds between the
pulp box and the couching roll u. The suction box shown in the drawings is
arranged for the formation of two air-tight or sealed chambers according to my
invention, but the number of such chambers is optional; one such chamber will in
many cases suffice while there may be more than two if thought desirable. The
box m is kept constantly supplied with water from any convenient source; its level
while the machine is at work will be maintained at about the point shown, any
tendency to rise above that level being counteracted by the suction of the surplus
through the suction pipes. In the suction box are three endless belts n nn of
india rubber or other suitable material; each of these belts passes round two
rollers PP that are free to turn on axes qq at right angles to the line of travel of
the moulds. The under edge of the side and end frames and cross bars of each
successive mould as this travels above the suction box bears closely upon each
belt n in turn, and the rollers are thereby caused to rotate and the belts to travel.
It will readily be understood that constant joints are thus formed between the
belts n and the under edge of the mould frames and cross bars. The first belt and
the second belt in conjunction with the successive cross bars d d and side frames bb
of the travelling moulds form the two sides of the first air-tight chamber and the
second belt and the third belt (when such is employed) similarly form the two sides
of a second air-tight chamber. The water in the box m forms the bottom of the
said chamber or chambers, and the pulp on the mould surface in conjunction with
the deckle straps 11 the top of same. The ends of the said chambers are formed
by boards or blocks tt and rubber faced plates rr in conjunction with the end
frames c c of the moulds; the plates are kept pressed by springs s s against the
mould ends, the top of these plates just clearing the bottom of the bars ff. The
springs ss are supported by the blocks t t which are fixed in the suction box m. If
the boards or blocks t t be extended so as to come in contact with the end
frames c c and be made quite level, they will form the ends of the sealed chambers
and in this case the plates and springs s can be dispensed with, and the frames
and cross-bars of the moulds can be flush with the bottom of the links carrying
them. In each air-tight chamber are the open ends of suction pipes vv which are
connected with vacuum pumps. Three suction pipes to each chamber will generally
be found a suitable number, but there may be a greater or lesser number. The
open ends of the pipes should be as near as practicable to the mould frames and
cross bars without coming in contact therewith.
It will readily be understood that when communication is opened with the pumps
a vacuum will be created in the air-tight chambers, and that the water or moisture
in the pulp lying on the surface of the moulds will be extracted as these moulds
pass successively over the said chamber.
In the modification represented in Figure 5 the second side of the air-tight
chamber instead of being formed by contact of the mould frames and cross bars

page_text: with an india rubber belt is formed by contact of said frames and cross bars with
strips of india rubber or other suitable material w w of which there may be two as
shown or more, fastened to the side of the suction box m.
In Figure 6 a represents the endless wire web which as it travels is in close
contact with the upper surface of the endless belts n n. The plates are at such
a position that they press partly against the sides of the web a' and partly against
the deckle straps l.
According to another arrangement which is represented in transverse section in
Figure 7 and in longitudinal section in Figure 8 I enclose or box in the under
surface of each of a series of travelling moulds with zinc, copper or other suitable
material as shown at a x, leaving an opening y in the middle, around which I hang
an edging or hood of india rubber or other suitable flexible material which
projects a few inches below the mould. All the joints of the zinc covering and
hood should be air-tight. Below the centre of the series of moulds is a longitudinal
suction or water box m to which are connected at intervals suction pipes leading
to a vacuum pump or pumps, the ends of these pipes projecting slightly above the
water in the box.
As the moulds travel along the machine in succession the hood of each yields
so as to pass over the end of and into the suction box m, the said end being
preferably rounded; the hood next yields as its leading edge passes over the first
suction pipe v, an inclined plane z¹ facilitating this movement. Immediately the
leading edge of the hood has passed over the suction pipe the said edge drops into
the water which thus forms an air-tight joint or seal around the hood; consequently
the vacuum pumps exhaust the air from below the mould as it passes over the
suction pipe and the moisture is therefore extracted from the pulp on the surface
of the mould. The process is repeated as the mould passes over the next suction
pipe and over as many more as may be required.
Instead of enclosing or boxing in the under surface of the moulds as above
described, the india rubber or other flexible material may be hung round the
edges of the moulds, the width of the suction or water box m being proportionately
increased and a greater number of suction pipes v being employed in the width of
the suction or water box; the moisture is thus extracted more quickly and
uniformly.
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
in respect of paper making machines is :-
1. The combination with a travelling paper making surface or paper former of a
suction water box below the line of travel of the said paper making surface, one or
more suction pipes in the said box, surfaces or beds in front of and behind the
suction pipes at such a level as to make close contact with the paper making
surface or its frames and cross bars, and means of making a joint at the sides of the
paper making surface or its frames, whereby in conjunction with the pulp upon
the paper making surface and with the water in the suction box an air-tight or
sealed suction chamber is constituted substantially as and for the purpose set
forth.
2. The combination with a travelling paper making surface or paper former, of
the suction box m, the suction pipes e, the rollers p, the endless travelling belts n
adapted to form close contact with the underside of the paper making surface or of
its frames and cross bars, the blocks or boards t t and the plates rr kept in contact
with the sides of the paper making surface or its frames, substantially as herein-
before described and shown in Figures 1, 2, 3, 4 and 6.
3. The several combinations of parts represented respectively in Figures 1, 2
and 3, Figure 5 and Figure 6 and hereinbefore described.
4. Constructing paper making machines substantially as hereinbefore described
with reference to Figures 7 and 8, that is to say with an edging or hood of flexible

page_text: material projecting below each of a series of travelling moulds so as to enter a
suction or water box fitted with suction pipes as and for the purpose set forth.
Dated this 16th day of March 1893.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.