Improvements on Paper Making Machines for Making the Surface of the Paper Equal on Both Sides.
Year: 1891

page_text: Date of Application, 16th Jan., 1891
Complete Specification Left, 14th Nov., 1891-Accepted, 16th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements on Paper Making Machines for Making the Surface
of the Paper Equal on Both Sides.
ROBERT BROWN Paper Maker 130 George Street Edinburgh GEORGE
MACKAY Paper Maker 130 George Street Edinburgh do hereby declare the
nature of this invention to be as follows:-
This invention has for its object improvements in making the surface of the
paper made at paper making machines equal on both sides, at present the paper
now made on paper machines is two sided, the under sided or wire side is much
rougher then the upper side of the paper which renders the paper thinner and
therefore when reamed the bulk of the ream is much less then when surfaced on
the paper machines by this invention, these objections are obviated. We reverse
the paper in its wet state in the following manner, when the pulp passes along the
machine wire on to the first press wet felt. We reverse the pulp in the wet state
by putting on an extra felt in the following manner. We add in front of the
present press rolls of the paper making machines two felt leading rolls and at this
point we introduce the extra felt and run the wet pulp on to this extra felt which
enables us to turn the damp or wet pulp on to the felts now used at the present
paper machines with any number of cylinders and at the machine with one cylinder
we pass the wet pulp through the first press roll and then reverse it by a second
felt. By doing this we get as before stated the surface of the paper equal on
both sides.
Dated this 15th day of January 1891.
ROBERT BROWN.
GEORGE MACKAY.
COMPLETE SPECIFICATION.
Improvements on Paper Making Machines for Making the Surface
of the Paper Equal on Both Sides.
We, ROBERT BROWN 130 George Street Edinburgh and GEORGE MACKAY
34 Howard Place Inverleith Row Edinburgh Paper Makers 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 :-
Our invention has reference to the working or travelling of the web of paper
when it is in its damp state, and so arranging the rollers, felts, and their adjuncts,
that this web of paper is so treated in its manufacture, as to equalise as far as
possible both sides of the paper.
It is well known that all classes of paper have more or less unequal surfaces, the
under side of paper which generally gets its first pressure against the wire
between the couch rolls and thereafter against the felt, between the press rolls
maintains a rougher surface than the top side of the paper and maintains this in a
more or less degree throughout, unless equalised with pressures given to it by
mechanisms, which tend to thin" the paper, or in other words to deteriorate
what is known in the paper trade as the "handle" or "feel."
This invention has for its object the obviating of the aforesaid. To give a
correct explanation we attach drawing which altho not to scale will shew clearly
one adaptation of our Patent.
This drawing shews the Patent applied to a paper machine with a single drying
cylinder.

page_text: On such machines the general practice is to have one or more press rolls and one
felt passing round the top couch roll, and thereafter between the press rolls and
drying cylinder.
Our invention as introduced shews the working of two felts.
A is the drying cylinder.
B. the couch roll with felt C. passing round it, and between cylinder and press
roll D. returning again to pass between cylinder and press roll E.
It will thus be seen that the first pressure the paper gets here against the
cylinder, is, with under side next to the cylinder, and the last pressure given
between press roll E. and cylinder is in the same manner.
The top side of the paper is brought into contact with press rolls F. and G.
felt H. being arranged to suit.
Felt C. from the points 1. and 2. will go to the continuous working passing if
necessary the ordinary arrangement for guiding, stretching, and washing.
In this Patent we reserve the number and position of rolls, either for a single
cylinder paper machine or otherwise in connection with the siding, surfacing or
otherwise treating the paper in its damp state.
The drawing herewith as aforesaid is not a scale drawing, and only meant to
show the system under which with a single cylinder paper machine our Patent can
be carried out.
Any number of rolls or cylinders marked A. B. D. E. F. and G. may be employed
for any special requirements.
The rolls R and their brackets can be placed to suit circumstances in any
number more or less to work, guide and stretch the felts C & H or any other
number of felts that may be arranged for.
In connection with a single cylinder machine, or a machine of this type with
more than one cylinder, a cleaning roll or drum I. can be introduced either in
connection with or separate from the ordinary "doctor."
The felt goes round couch roll B, and lifts the paper off the wire at that point,
then passes through press roll D on to the second felt H. then it is carried to press
rolls G and at this point the paper is reversed before going through press roll E.
Any of the press rolls so far as shewn by D. E. F. & G. can be arranged to
modify the pressure for or against either side of the paper.
And we reserve to ourselves the application of vacuum boxes on machines in
connection with either or any of the felts.
We reserve also to ourselves while having lodged the foregoing Specification and
drawing privilege of adoption to all classes of paper machines.
Having now particularly described the nature of our said invention we declare
that what we claim is.
The equalization of both sides of a web or webs of paper, in its damp or moist
state during the course of its manufacture or the reverse (i.e. that the surfaces of
the paper can be kept rough or smooth as may be arranged through the manipu-
lation of, and fixing of parts of machinery composed of rollers, felts, wires, and
their immediate connections.
February 6th 1892.
ROBERT BROWN.
GEORGE MACKAY.