Improvements in or relating to Pulp Strainers of Paper Making Machines.
Year: 1893

page_text: Date of Application, 23rd Nov., 1893--Accepted, 27th Jan., 1894
COMPLETE SPECIFICATION.
Improvements in or relating to Pulp Strainers of Paper Making
Machines.
I DAVID NOBLE BERTRAM of St. Katherines Works Sciennes Edinburgh
in the County of Midlothian North Britain Engineer 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 improvement in or relating to pulp strainers of paper
making machines.
My said improvements are more especially applicable to the class of machines
described in the Specification of my former application for Patent No. 11943
of 17th June 1893 that is to say to those machines having the strainer plates
placed on an angle the apex of the strainer plates being long ways of the machine,
and the pulp flowing down from the apex over the entire area of the plates.
Hitherto there has been a considerable dead or non-straining area existing in all
styles of strainer plates, and in the case of those plates placed on an angle is
objectionable as the clean pulp flows over such dead parts, and mixes with the
refuse thereby causing a greater body of clean pulp to be separated from the refuse
matter.
In carrying out my invention, I form or cut the slits of the strainer plates in
such a manner that they run parallel, longitudinally, but in angular rows from the
apex of the strainer plates, as is shown in Figure 1 of the accompanying drawings,
which is a plan of the underside of a strainer plate showing the slits A cut in
angular rows from the apex B. By the said angular, or other equivalent arrange-
ment of the slits, the downward flow of the pulp is always intercepted by slits and
thus, by reducing the quantity of such clean pulp flowing to auxiliary strainer, the
cuts of the plates in the auxiliary strainer can be made finer, thus greatly increasing
the undoubted benefits derived from the use of an auxiliary strainer.
My improvements in pulp strainers further relate to the alteration of the stroke
of the diaphragm. As shown in part sectional elevation Figure 2 and cross section
Figure 3, I form the end of the crank shaft C with a tapered portion D having its
centre line d running eccentrically to the centre line c of the shaft C. On the
outside of the tapered portion D, I mount an elliptical sleeve E, the outside of which
is eccentric and the inside concentric to the tapered portion D of the shaft C; the
said sleeve E, after being set so as to give the necessary stroke, is then bound up.
against the end plate or collar F, which is formed on or attached to the shaft C,
by means of a double screw G the front end g of which works in the end of the
tapered portion D, and it is of less diameter and screwed to a finer pitch than the
back portion g', which works in the end of the sleeve E as shown, so as to form a
powerful and gradual means for engaging or disengaging the shaft and sleeve for
setting purposes. In order to enable the sleeve E being set to any desired position,
I form the face of its inner end e with a number of grooves or recesses e¹ around the
one half of its circumference, as shown more particularly in Figure 3;
said grooves.
or recesses el engaging with a key or projection ƒ screwed, pinned, or otherwise
attached to the end plate or collar F, in such a manner, that the throw of the crank
can be varied as desired.
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 1
claim is :-
Lot In

page_text: arranging or forming the slits of the strainer plates in angular rows, or in an
equivalent form, substantially as and for the purposes herein before described and
shown in the accompanying drawings.
2nd. In paper pulp strainers, the means whereby the stroke of the diaphragm may
be altered as desired substantially as hereinbefore described and shown in the
accompanying drawings.
Dated this 22nd November 1893.
JOHNSONS,
115, St. Vincent Street, Glasgow, Applicant's Agents.