Improvements in and relating to the Pulp Strainers of Paper Making and like Machines.
Year: 1895

page_text: Date of Application, 8th Nov., 1895
Complete Specification Left, 30th Apr., 1896-Accepted, 6th June, 1896
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Pulp Strainers of Paper
Making and like Machines.
We,
DAVID NOBLE BERTRAM, Engineer, of St. Katherine's Works, Sciennes,
in the City and County of Edinburgh, and JAMES BLAINE, Paper Maker, and
THOMAS MARSHALL, Engineer, both of Denny, Stirlingshire, do hereby declare
the nature of our invention to be as follows:-
This invention has reference to an improved arrangement and combination of
appliances or apparatus for absolutely preventing wash back of the pulp over the
plates of strainers, the vats of which are stationary, with plates placed on the
angle; or having rocking or oscillating motion, or any movement on the vat whereby
the pulp is liable to be washed over the plates of any strainer having one side of
the vat only lifted, and thus causing a wash the one way.
According to these improvements, on the side of the vat which is lowered there
are placed two brackets, one at either end which act as hinges. On the shaft there
is an arm fixed. At the opposite end to the hinge, a board is fixed to this arm,
which board, when the strainer is in its normal position, forms a joint on the
surface of the plates. This board is lifted by an arrangement thus:-
A fixed lever on the shaft, the ends of which form the hinge just described
above, comes in contact with vertical rod, which rod is fixed to the foundation, and
on the top, below the eye of the lever with which it comes in contact, a regulating
collar is fixed so as to give the desired amount of lift. One of these vertical rods
and fixed levers is at either end of the vat, or it may be only at one end.
The effect of this arrangement is to give a thorough wash over the plates and
absolutely prohibit any of the refuse matter discharged from coming back on the
surface of the plates, as when the strainer is at work and the vat at rest, the refuse
which has been discharged into the channel from which it is conveyed to the
auxiliary strainer, has been emptied, therefore, when the vat is lowered and
the board raised, a very sudden wash takes place, thus thoroughly cleansing the
plates.
The arrangement of levers is such that the motion of the vat is multiplied to the
board so that should the vat be lowered, say, a half inch, the board is lifted more
than one inch, giving a large opening with a small movement of the vat.
Dated this 7th day of November 1895.
W. R. M. THOMSON & Co.,
96 Buchanan Street, Glasgow, Agents.
Improvements in and relating to the Pulp Strainers of Paper
Making and like Machines.
We, DAVID NOBLE BERTRAM, Engineer, of St. Katherine's Works, Sciennes,
in the City and County of Edinburgh, and JAMES BLAINE, Paper Maker, and
THOMAS MARSHALL, Engineer, both of Denny, Stirlingshire, do hereby declare the
nature of our invention, and in what manuer the same is to be performed, to be
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particularly described and ascertained in and. by the following statement in writing,
that is to say :-
This invention has reference to an improved arrangement and combination of
appliances or apparatus.for absolutely preventing wash back of the pulp over the
plates of strainers, the vats of which are stationary, with plates placed on the
angle or having rocking or oscillating motion, or any movement on the vat
whereby the pulp is liable to be washed over the plates of any strainer having one
side of the vat only lifted, and thus causing a wash the one way :-
And in order that our said invention and the manner of performing or carrying
same into practice may be properly understood, we have hereunto appended an
explanatory sheet of drawings in which the same. reference. letters. are used to
indicate corresponding parts in all the figures where shown.
Figure 1 is an elevation partly in section of a pulp strainer with rocking vat, as
fitted with one arrangement of our improvements.
Figure 2 is a similar view of a strainer in which the vat is stationary, and
Figure 3 is a corresponding plan view of same.
Figures 4 and 5 are side elevation and plan views of the lever clutch and collar
fitted on the operating shaft of stop board in the arrangement shown in Figures 1
, and 2, and Figure 6 is a detached elevation showing an alternative way of operating
the connecting rod of stop board lever from that shown in Figure 2.
Referring to Figure 1 of these drawings
"This strainer is constructed and the vat operated to rock or oscillate in the same
manner as described and shown in the Specification of Patent No. 4771 of 1894.
But according to these improvements on the side of the vat A which is lowered
'there are placed two brackets, similar to that shown at a in Figure 3, one at either
. end which act as hinges. On the shaft a 1 there is an arm a 2 fixed. At the
. opposite end to the hinge a, a board a 3 is fixed to this arm a 2 which board, when
the strainer is in its normal position, forms a joint on the surface of the plates B.
This board a 3 is lifted by an arrangement thus:Fixed lever b on the shaft a 1-
the ends of which form the hinge a just described above comes in contact with
vertical rod, c which rod is fixed to the foundation Z, and on the top, below the
eye b1, of the lever b with which it comes in contact, a- regulating collar 2 is
fixed so as to come in contact earlier or later with the lever and give the desired
amount of lift. One of these vertical rods c and fixed levers 6 is at either end of
'the vat or it may be only at one end, or at the centre as shown in Figure 3.
The effect of this arrangement Figure 1 is to give a thorough wash over the
plates B and absolutely prohibit any of the refuse matter discharged; from coming
back on the surface of the plates, as when the strainer is at work, and the vat A at
rest, the refuse which has been 'discharged into the channel C from which it is
conveyed to the auxiliary strainer, has been emptied, therefore, when the vat A is
lowered and 'the board a 3 raised; a very sudden wash takes place, thus thoroughly
cleansing the plates B.
The arrangements of levers is such that the motion of the vat A is multiplied to
the board a 3 so that should the vat be lowered, say, a half inch, the board is lifted
more than one inch, giving a large opening with a small movement of the vat.
Referring to the arrangements shown in Figures 2 to 5, here the vat A remains
stationary and the stop.board a 3 is. lifted automatically a convenient number of
times per minute, so as to liberate 'the pulp accumulated or dammed up behind it
and cause a rush of same over the plates B which are here set at a slight angle, and
the refuse is dislodged into the channel C from which it is conveyed to the auxiliary
as usual.
The stop board a 3 is actuated by worm gear at k which worm gear. is driven
from the rotating diaphragm shaft, this worm gear being employed for reducing
..the speed and consisting of two worm wheels and two worms revolving in a case 'K,
which may be partly filled with oil, and is the same as described for the tilting
motion in the aforesaid Patent No. 4771 of 1894.

page_text: On the opposite end to which the worm spindle is driven there is a disc d fixed,
and to this disc d a rod d 1 is fixed at its one end eccentrically to a crank pin d 2
and this rod is at the other end, coupled up to a lever b on the stop board hinge
rod a 1 which passes along the full length of the strainer plates.
As the disc d revolves, it pulls down the lever b the rod d 1 being coupled to
the lever b by an open gab or other suitable joint at 63, the eye 62 on which
lever 6 works on the hinge rod a 1 loose, and is held in position by a loose collar e
and on this eye b 2 there is formed a clutch claw 64, which comes in contact with
a similar claw e 2 formed on a boss el which is fixed to the hinge rod a 1, thus the
hinge rod moves when such contact takes place, and lifts the board a 3 the board
being connected to the rod by cast iron arms a 2, which are fixed to the rod a 1,
and at the opposite end the board is fixed to them.
The hinge rod a 1 is carried in the brackets a fitted to either end of the strainer
vat A. The amount of lift can be varied by adjusting. the bolt and nuts e 3 and
turning round the clawed clutch e 1 e 2, so as to come earlier in contact with that 64
on the lever eye b 2.
Instead of so actuating the board a 3 by the clutch arrangement, a connecting
rod d 1 with a slot end d 3 can, as shown in Figure 6, be applied to the disc d, the
the pin d 2 on the disc d working in the slot d 3, and pulling down the lever b so as
to give the amount of lift desired.
The rod d 1 which couples up the disc d to the lever b which actuates the board d 3
can be made with right and left hand screws similar to those N on the connecting
rods G and H of my aforesaid Patent, so as to give more or less lift, namely by raising
the rod more lift is given, and vice versa, less lift by lowering it, and the deflection
on the rod is compensated for by the joint which is formed on the end of lever
or hinge rod.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
First. In pulp strainers fitted with either stationary or moveable vats, the
method of preventing wash back of the pulp over the strainer plates by means of a
stop board, substantially as and in the manner herein described in reference to and
shown in the accompanying drawings.
Second. In pulp strainers fitted with either stationary or moveable vats, the
arrangement and use of a stop board connected to a transverse shaft, and operated
substantially as and for the purposes herein described in reference to and shown in
the accompanying drawings.
Dated this 24th April 1896.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.