IMPROVEMENTS IN APPARATUS FOR STRAINING PAPER PULP."
Year: 1880

page_text: LETTERS PATENT to Henry White, of Denny, in the County of Stirling, North
Britain, for an Invention of "IMPROVEMENTS IN APPARATUS FOR STRAINING
PAPER PULP."
PROVISIONAL SPECIFICATION left by the said Henry White at the Office
of the Commissioners of Patents on the 24th January 1880.
HENRY WHITE, of Denny, in the County of Stirling, North Britain.
MENTS IN APPARATUS FOR STRAINING PAPER PULP."
" IMPROVE-
The said Invention relates to apparatus wherein the strainer through which the
pulp is drawn revolves in the trough or receptacle containing the pulp. According
to the said Invention there is fixed in the strainer at about the middle of its length
a ring or disc, preferably of brass, having fixed to one side by means of a flexible
joint of india-rubber or equivalent substance, the flange of a pipe preferably of
copper. This pipe opens into one of the divisions into which the strainer is divided
by the disc aforesaid and passes out at the other end where it has openings, and is
furnished with a short rod capable of sliding in a stuffing box at one end of the
strainer. Connected to this pipe by arms, so as not to obstruct the opening thereof,
is a rod which may be of iron covered with india rubber to protect if from the
action of acids in the pulp, the said rubber extending over the arms aforesaid to
form a flexible joint with the pipe, this rod passing through a stuffing box at the
other end of the strainer where it receives the herein-aftermentioned to-and-fro
motion. When the apparatus is in action the strainer is rotated in the pulp trough
or receptacle and a longitudinal motion is given to the spindle, and the pipe passing
through the said strainer and the disc in the said strainer is moved to and fro so
as to give a sucking action alternately on either side thereof and draw the pulp
through the sides of the strainer alternately into either part into which its interior
is divided by the said disc; the strained pulp passing from the one part through
the central pipe aforesaid and out at its open end, and from the other part through
an annular opening at the end around the said pipe.
The motions of the strainer and of the spindle may be obtained in the ordinary
or other convenient manner.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry White in the Great Seal Patent Office on the 21st July
1880.
HENRY WHITE, of Denny, in the County of Stirling, North Britain.
MENTS IN APPARATUS FOR ŠTRAINING PAPER PULP."
"IMPROVE-
My said Invention relates to apparatus wherein the strainer through which the
pulp is drawn revolves in the trough or receptacle containing the pulp. According
to the said Invention there is fixed in the strainer a disc to which a to and fro
movement is imparted, so as to give a sucking action and draw the pulp through
the sides of the strainer and force the strained pulp therefrom.
And in order that my said Invention may be properly understood, I now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, reference being had to the
accompanying Drawings, and to the letters and figures marked thereon, that is to
say
Figure 1 represents in longitudinal vertical section an apparatus constructed
according to my Invention; Figure 2 is a transverse section of the strainer on the
line 1, 2, Figure 1. The strainer A is formed with hollow trunnions a at each end,
by which trunnions the said strainer is mounted in stuffing box bearings b in the
trough or vat B, in which the unstrained paper pulp is contained. In the interior
of the strainer A and at about the middle of its length is fixed to the strainer rails
a ring c (by projections on the said rails engaging in recesses in the ring c or
otherwise), the said ring being preferably of brass. To this ring is fixed by a
flexible joint (formed by the ring d of india rubber or other suitable flexible
substance) a flange or disc e, shewn separately in Figure 3, the india rubber ring d
being confined at its outer circumference between the ring c and the confining
ring c and at its inner circumference between the disc e and the confining ring e,
the said rings c and c and disc e and ring e² being fixed together by pins, or rivets,
or screws, the whole forming an air-tight division between the two compartments
of the strainer, which division I will term the division X. The spaces at x between
the sides of the strainer and the ring c will of course be closed. Through a central
opening in the disc e one end of the pipe f passes, the other end of the said pipe
passing out through the hollow trunnion a at one end of the strainer and through
the receptacle G for the strained pulp, and its end being furnished with a short
rod fcapable of sliding in a stuffing box g in the side of the said receptacle G.
Connected to the disc e is a rod h, the said disc e being furnished with a bracket
piece connected thereto by arms e², so that the said rod h does not obstruct the
opening of the pipe f. The other end of the said rod passes into the hollow
trunnion a at the other end of the strainer and through a guide a³ therein. The
flexible disc at i is connected by rings or collars is to the rod h and by the ring is
to the strainer, giving a flexible and air-tight joint. The interior of the strainer
is divided by the division X into two compartments or divisions Y and Z. One of
the hollow trunnions a may be furnished with a pulley by which a rotatory motion
may be given to the strainer A in the trough B, or other suitable and convenient
means of giving this motion to the strainer may be adopted. A to and fro motion
is at the same time given to the rod h and pipe f and the disc e of the division X
by an eccentric or any suitable or convenient and well known means by which such
a movement can be effected.
When the apparatus is in operation, the unstrained pulp being in the trough or
vat B, the strainer A is rotated therein and a longitudinal motion is given to the
rod as aforesaid, and the disc e of the division X is thereby moved to and fro so
as to give a sucking action alternately on either side thereof and draw the pulp
through the sides of the strainer alternately into either part Y and Z, into which

page_text: its interior is divided by the said division X, the strained pulp passing from the
one part Y into the pipe fand therefrom through openings (as at f³) therein, and
from the other part Z through the annular opening between the exterior of the
pipe fand the interior of the hollow trunnion a into the vat or receptacle G for the
strained pulp. The rod h may be of iron and may be covered with india rubber
which may extend over and be attached to the bracket of the disc e, the said india
rubber then forming an elastic attachment in place of the rigid one formed by the
connection of the said rod h to the said bracket, as illustrated. The strainer A is
shewn in the Drawings as of a square figure in transverse section, but it may be
of a circular or any suitable section. The rings d and I prefer to make of sheets
or layers of india rubber and canvas. The pipe may be stationary if desired, the
disc e working upon its end; but I prefer the arrangement shewn, as it allows the
sliding bearings to be outside the trough and clear of the pulp. Instead of
employing the pipe f to conduct the pulp to one end of the strainer the said pipe
may be dispensed with, and the pulp may be delivered at both ends of the strainer
through the hollow trunnions, but I prefer the arrangement shewn. Although I
have shewn the division as being situated in the middle of the strainer A, yet I do
not limit myself to this position as it may be otherwise placed; for example, in
small strainers the said division X may form one end of the strainer so as to be
single acting.
Having now described and particularly ascertained the nature of my said
Invention, and the system, mode, or manner, in or under which the same is or may
be used, or practically carried into effect, I would observe in conclusion that I do
not limit myself to the precise details hereinbefore described and illustrated in the
accompanying Drawings, as the same may be varied without departing from the
nature of my Invention, but what I claim as the Invention secured to me by the
hereinbefore in part recited Letters Patent is,-
First. The improved apparatus for straining paper pulp constructed or arranged
essentially as herein before described and illustrated in the accompanying Drawing,
wherein the essential feature is the combination with the strainer of a disc or
division to which a to and fro or pulsating movement is given, essentially as and
for the purpose described, whether it be used as a double or as a single acting disc
or division.
Second. The combination with the said pulsating disc or division of a pipe (ƒ)
for causing the delivery of the strained pulp from both divisions of the strainer
at one end thereof, essentially as described and illustrated in the accompanying
Drawings.
In witness whereof, I, the said Henry White, have hereunto set my hand
and seal, this Fifteenth day of July, in the year of our Lord One thousand
HENRY WHITE. (L.S.)