Improvements in Apparatus for Straining Paper Pulp.
Year: 1891

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 18 of the Patents, &c. Act, 1883), as allowed by
the decision of the Comptroller General of the 29th day of May 1896.
Date of Application, 7th Oct., 1891
Complete Specification Left, 27th June, 1892-Accepted, 30th July, 1892
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Straining Paper Pulp.
I, JOHN WHITE, Manager to Messieurs James Bertram and Son, Leith Walk
Foundry, Edinburgh, in the County of Mid Lothian, North Britain, do hereby
declare the nature of this invention to be as follows, that is to say :-
This invention relates to the class of pulp-straining apparatus in which flat plates
ordinarily fixed in a horizontal position are employed; and it consists in imparting
an oscillating or rocking motion to the vat or vessel in which the straining operation
is effected, and in constructive arrangements connected therewith, whereby the
action is improved and various practical advantages are obtained.
In carrying out the invention the strainer vat is supported by journals resting in
bearings on the fixed framing and is made to oscillate or rock by means of a con-
necting rod from a slowly rotating adjustable crank pin; or the motion may be
derived from an eccentric or from a cam which last can be shaped to give whatever
particular motion may be found best in practice.
Beneath the strainer plates in the vat pulsating diaphragms are arranged in a
usual manner and are made to reciprocate by cranks on a rotating shaft situated
directly below and parallel to the rocking axis of the vat. The strained pulp passes
from the vat through a hollow trunnion which is in the rocking axis and which
extends into a box having an overflow outlet the bottom of which is adjustable so
as to maintain the desired head of pulp in the straining vat.
The strainer vat is made with a channel along one side, or with channels along
the two sides of the strainer plates; and each channel is provided with one or more
valves the spindles of which extend down through the valve openings. Stationary
gutters are. provided under the sides of the vat, and in these adjustable stop pins
are provided, which cause the valves to open on the valve spindles encountering the
stop pins. This takes place at either side when the oscillating or rocking motion
lowers that side of the vat.
The oscillating or rocking motion causes the pulp to wash across the strainer
plates, and the wash removes fibres or inaterials which refuse to go through the
strainer plates, taking them into the side channels whence they pass off through
the valves.
Dith day of October 1891.

page_text: -
Improvements in Apparatus” or Straining Paper Pülp.
I, JOHN WHITE, Manager to Messieurs James Bertram and Son, Leith Walk
Foundry, Edinburgh, in the County of Mid Lothian, North Britain, do bereby
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, that is to say :-
This invention relates to the class of polystraining apparatus in, which flat plates
ordinarily fixed in a horizontal position are employed; and it consists in imparting
an oscillating or rocking motion to the vat or vessel in which the straining operation
is effected, and in constructive arrangements connected there with whereby the
action is improved and various practical advantages are obtained.
And in order that my said invention and the manner of performing the same may
be properly understood.I, hereunto-append,'two sheets of explanatory drawings to
be hereinafter referred to in particularly describing my improvements.
Figure, 1,on Sheet, 1, of the drawings is a plan, and Figures, 2, and, 3, are sectional
side and end elevations of one modification of my improved pulp strainers; and
Figures, 4, 5, and 6, on Sheet,2,are transverservertinal sections offother modifi-
cations of the upper part of the apparatus.
In these drawings.thesame reference numerals are used to mark the same or like
parts,wherever they are repeated..
In carrying-out my invention--the strainer vat, 7, is supported by journals, 8, 9,
fixed in downward.end.extensions, 10, 11, fixed to the vat, these journals resting in
bearings, 12, 13,. on a: fixed.bedframe, 14. The vat 7, is made to oscillate on rock:
by means of a.connecting rod,i.15, jointed to it and to auslowly rotating.crank
pin, 16; or the motion might be derived from, an eccentric.or.fromia.camp which
last can be shaped. to. give. whatever particular. motionumay-be found, best-in
practice.
Beneath the strainer plates, 17, (which are not showminguel) in the vat:7,
a: pulsating, diaphragm,.18, is arranged in a uanal manner, and is made: to reciprocate
by means of rods, 19, fixed to them..and jointedapamsmall-throw cranks,.2011on:a
rotating shaft, 21, situated directly below the rat and in line with cor rparallel to
the axis on. which the vat, rocks.. The, shaft, 21, is carried sinabearings,22;on. the
bedframe,. 14, and has on,it,a pulley, 23, força driving, belts. The diaphragms are
borne up by adjustable springs, 24, resting on crossbars; 25, fixed to the vat,.7.
For giving the rocking motion; to the vataseparate, shaft. 265 is provided, in
“bearings,:27, and having on,it,a..pulley, 28, for a driving belt. The shafty.20, by
a pinion, 29, and spurwheel, 30, drives a second-motion shaft, 31, the crank pin, 16,
for giving, the rocking motion, being on the spurwheel, 30...
The strained pulp, passes from,.the, space below the strainer plates;.17,.in. the
vat, 7, down one, 11, of the-end-parts which is made hollow,.and.Bhrough a hollow
trunnion, 32, which is concentric with the axia on which the sabrooks; and which
extends through a stuffing, box.into aboz, 33, having an overflow outlet, 34, the
bottom of which is adjustable, so as to maintain the desired head'of pulp,in the
strainer vat, 7.
The strainer vat, 7, is made.with channels,,35, along each side:(on it might.be, a
single channel along one side) of the strainer plates, al 7, and when the pulp contains
fibres which refuse to go through the-strainer-plates, such fibres accumulate in the
channels, 35, from which they may be removed from time to time. Orpassshown
in Figure, 4, each channel, 35, may be provided. with one or more valve Guilets, 36,
through which. the refusing fibres pass out in small quantities at a time into
stationary gutters, 37. The valve outlets, 36, are closed by weighted plungers, 38,
fitted to work in guides fixed to the vat, and connected by chains, 39, passing over

page_text: pulleys, 40, to hooks, 41, fixed to a bracket or arm secured to the stationary part
of the machine. As each side of the vat descends with the rocking motion the
chain, 39, on that side tightens, and draws the plunger, 38, up out of the valve
outlet, 36, so as to let some pulp escape from the channel. The duration of
opening may be adjusted by lengthening or shortening the chains, 39; and the
chains may be unhooked, whenever, it is considered undesirable to allow any pulp
to escape from the channels, 35.
The strainer vat, 7, may be fitted with a single strainer plate, 17, and with a
single pulsating diaphragm, 18, as in the modifications shown in Figures 1, to 4, or
it may be fitted with two strainer plates, 17, and two pulsating diaphragms, 18, as
shown in Figures 5, and 6, the two strainer plates, 17, being either level with each
other as shown in Figure 5, or slightly inclined to each other as shown in Figure 6.
The two pulsating diaphragms, 18, may be worked by means of crossheads, 42, to
which the connecting rods, 19, are fixed.
The oscillating or rocking motion of the strainer vat, 7, causes the pulp to wash
across the strainer plates, 17, and the wash removes fibres or materials which will
not go through the strainer plates, taking them into the side channels, 35, whence
they may pass off through the valve outlets, 36.
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 pulp straining apparatus of the type in which the usual pulsating diaphragm
under the strainer plates is operated from a rotating shaft below, imparting an
Oscillating or rocking motion to the vat or vessel in which the straining operation
is effected, substantially in the manner herein before described.
2. Forming the strainer vat with a channel (35) at one or at each side and
providing one or more periodically opened valve outlets in connection with such
channel substantially as and for the purposes hereinbefore described.
Dated this Twenty-fifth day of June 1892.
EDMUND HUNT,
Applicant's Agent.