IMPROVEMENTS IN APPARATUS FOR STRAINING PULP
Year: 1871

page_text: LETTERS PATENT to John Jarvis, Manager, and James Robb,
Engineer, of the Dalmarnock Paper Works, in the County of
Lanark, North Britain, and Andrew Masson, Engineer, of Edin-
burgh, in the County of Mid Lothian, North Britain, for the
T
PROVISIONAL SPECIFICATION left by the said John Jarvis, James
Robb, and Andrew Masson at the Office of the Commissioners of
Patents, with their Petition, on the 14th June 1871.
We, JOHN JARVIS, Manager, and JAMES ROBB, Engineer, of the
Dalmarnock Paper Works, in the County of Lanark, North Britain, and
ANDREW MASSON, Engineer, of Edinburgh, in the County of Mid
Lothian, North Britain, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR STRAINING PULP," to be as
follows, that is to say :-
This Invention relates to improvements whereby pulp straining
apparatus whilst being thoroughly efficient is simplified in construction

page_text: and action and rendered less liable to get out of order than existing
apparatus for the same purpose.
The kind of apparatus to which one modification of the improvements
is applied is one in which a casing in the form of a four-sided prism
with perforated or permeable sides and placed horizontally revolves
about a horizontal axis in a trough into which the pulp to be strained
is poured. The pure pulp is drawn into the casing, and passes off from
one end by the tubular shaft; and heretofore the action has been
produced by a species of bellows working inside the casing with a short
rapid reciprocation.
By the present Invention plain discs, which may be perforated or not,
are substituted for the bellows, and are placed alternately with discs
fixed to the casing. These discs are made to reciprocate by means of a
shaft on which they are fixed, or in any convenient way; or the motion
may be given to the casing and the discs attached thereto, whilst
intermediate discs on a shaft or bar are kept stationary.
By another improvement the casing is kept stationary or non-revolving
being, by preference, made in the form of a three-sided prism, with one
side disposed horizontally at the bottom, whilst the outlet for the
suitable point.
strained pulp may be connected to the casing at any
The internal discs or reciprocators may be of any convenient form, as
almost any object which is made to reciprocate or vibrate rapidly inside
the casing will effect the desired purpose.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Jarvis, James Robb, and Andrew Masson, 2
in the Great Seal Patent Office on the 13th December 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN.
JARVIS, Manager, and JAMES ROBB, Engineer, of the Dalmarnock Paper
Works, in the County of Lanark, North Britain, and ANDREW MASSON,
Engineer, of Edinburgh, in the County of Mid Lothian, North Britain, a
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of June, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-

page_text: fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said John Jarvis, James Robb, and Andrew
Masson, Her special licence, that we, the said John Jarvis, James
Robb, and Andrew Masson, our exccutors, administrators, and assigns,
or such others as we, the said John Jarvis, James Robb, and Andrew
Masson, our executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for " IMPROVEMENTS IN APPARATUS FOR STRAINING PULP," upon the
condition (amongst others) that we, the said John Jarvis, James
Robb, and Andrew Masson, our executors or administrators, by an
instrument in writing under our, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that we, the said John Jarvis, James Robb, and
Andrew Masson, do hereby declare the nature of our said Invention,
and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement in writing,
reference being had to the accompanying Drawings, that is to say :—
Our said Invention relates to apparatus whereby pulp straining
apparatus whilst being thoroughly efficient is simplified in construction
and action, and rendered less liable to get out of order than existing
apparatus for the same purpose.
And in order that our said Invention and the manner of performing
the same may be properly understood, we hereunto append a Sheet of
explanatory Drawings showing by way of example two of the various
modifications of which our improved apparatus is susceptible.
In these Drawings the same reference numerals are used to mark the
same or like parts wherever they are repeated.
The kind of apparatus to which one modification of our improvements
is applied is one in which a casing 1, such as is shown in longitudinal
section in Figure 1, in the form of a four-sided prism with perforated
or permeable sides 2, and placed horizontally, revolves on trunnions 3, 4,

page_text: about a horizontal axis in a trough (not shown) into which the pulp
to be strained is poured. The pure pulp is drawn into the casing 1,
and passes off from one end by one of the hollow trunnions 4; and
heretofore the action has been produced by a species of bellows working
inside the casing with a short rapid reciprocation.
By our present Invention plain discs 5, which may be perforated or
not, are substituted for the bellows, and are placed alternately with
discs 6 fixed to the casing.
Figure 2 is a face view of one of the moving discs 5, which are made
to reciprocate by means of a shaft 7 on which they are fixed, and which
passes out through a stuffing box 8 in one of the trunnions 3, and is
actuated in the ordinary way. The discs 5 are spaced and held on the
shaft by means of flanged tubes 9, the series of tubes and discs being
fixed by means of screw nuts 10 at the inner end of the shaft. The
stationary discs are fixed to the internal framing of the casing 1, and are
formed with flanged centre eyes to guide the shaft 7, the tubes 9
on which are formed with bosses at the parts working through the
stationary discs. The reciprocating motion may be given to the casing 1
with the discs 6 attached to it, the shaft 7 being held stationary with
the discs 5 on it.
By another improvement we make the casing 1 quite stationary or
non-revolving, being, by preference, made in the form of a three-sided
prism, as shown in transverse vertical section in Figure 3, and with
one side disposed horizontally at the bottom. The outlet 11 for the
strained pulp may be connected to the casing at any suitable point.
In the example shown in Figure 3 the moving discs 5 aro hinged
to the top of the casing, and are made to reciprocate by lugs on a
reciprocating shaft or bar 7 below.
The internal fixed or reciprocating discs 6, 5, may be of any con-
venient form, whether the casing be revolving or non-revolving, as almost
any object which is made to reciprocate or vibrate rapidly inside the
casing will effect the desired object.
We find a reciprocating stroke (at the centres of the discs) of from
three-eighths to one quarter of an inch, with a speed of about 300
strokes per minute to be satisfactory and efficient.
Having thus particularly described our said Invention, and the
manner of performing the same, we have to state that we do not

page_text: restrict ourselves to the precise details hercin described or delineated,
but that what we believe to be novel and original, and claim as the
Invention secured to us by the hercin-before in part recited Letters
Patent is,―
1. The applying of simple reciprocating or vibrating discs instead of
bellows to pulp straining apparatus, as herein-before described.
And, 2. The combining of a non-revolving strainer casing with
internally fixed discs alternated with reciprocating or vibrating discs as
herein-before described.
In witness whereof, I, the said James Robb, on behalf of the said
John Jarvis, myself, and the said Andrew Masson, have hereunto
set my hand and scal, this Twelfth day of December, in the year
of our Lord One thousand eight hundred and seventy-one.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JAMES ROBB. (L.s.)