Improvements in Straining Apparatus for Straining Paper Pulp and other similar materials.
Year: 1892

page_text: Date of Application, 13th May, 1892
Complete Specification Left, 13th Feb., 1893-Accepted, 18th Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in Straining Apparatus for Straining Paper Pulp and
other similar materials.
We, FRANK LIONEL ROECKNER, of Two Water's Mill, Boxmoor, in the
County of Hertford, and RAMSEY LLEWELLYN ROECKNER, of 15 St. Lawrence
Road, North Kensington, in the County of Middlesex, Paper Makers, do hereby
declare the nature of the said invention to be as follows:-
:—
This invention relates more especially to straining apparatus of the kind
described in the Specification of an English Patent No. 7932 granted to Carl
Heinrich Roeckner and Frank Lionel Roeckner and dated 30th June 1885.
The strainers described in the above mentioned Specification are of cylindrical
form, contained in the pulp vat and made to oscillate through a small are more or
less rapidly on their axes; they are generally closed at one end, and they open at
the other end into a vat where the strained pulp is received. It is obviously
necessary to connect the strainers with the vat for receiving the strained pulp by a
joint so arranged that while no pulp can pass to the latter vat without passing
through the strainers the latter shall be free to perform their oscillatory motions.
This is effected according to the aforesaid Specification by means of indiarubber
or other suitable packing round the end of the strainer. It is found in practice
that this form of joint wears out somewhat rapidly and is expensive to renew, and
one of the objects of the present invention is to produce a joint which will fulfil the
desired conditions and will be more durable and less expensive to renew than
the one above referred to. For this purpose instead of leaving the outlet of the
strainer of the full diameter of the strainer cylinder as heretofore, we make it con-
siderably smaller by contracting it with a conical or other suitably shaped adjutage
and we then connect this contracted opening with the opening at the end of the
pulp vat by means of a piece of indiarubber or other suitable pipe or hose which is
sufficiently flexible to allow of the oscillating motion of the strainer on its axis
without unduly straining the said pipe by the twisting action incidental to that
motion.
The connecting pipe or hose may be of any suitable section, and plain or
corrugated and strengthened with wire internally or externally or not as may be
required, or it may be twisted in a manner similar to that employed as the closing
means of certain kinds of indiarubber tobacco pouches for example but of course
not sufficiently twisted in that way to reduce the area of the passage through it
below what is necessary for the passage of the required quantity of strained.
material.
.
The said pipe may be secured on to the nozzle of the adjutage and on to the
flange surrounding the opening through the end of the vat so as to prevent
the passage of pulp except through the slits of the strainer by being bound round
with wire, but preferably by means of clamping hoops tightened up by clamping
screws.
According to another arrangement the outlet opening is placed at a suitable
point in the circumference of the strainer, (which may be of cylindrical, prismatic,
barrel-shaped or other suitable form, either plain or corrugated) and we connect
such outlet opening with a corresponding opening in the side or bottom of the vat
by means of a piece of flexible pipe or by a connection in the form of a bellows
which has plenty of lateral flexibility to enable the strainer to make its oscillatory
motions without overstraining such connection. When this last described outlet
connection is employed, both ends of the strainer may be closed, or an outlet from

page_text: the end of the strainer and another from some part of the circumference may be
employed at the same time.
We sometimes employ an outlet at each end of the strainer and sometimes
several outlets from the circumference thereof with or without the outlet or outlets
at the end or ends. The greater the number of outlets employed the smaller may
be the diameter of the flexible outlet pipes, and thereby the smaller will be the
wear and tear thereof due to the bending or twisting by the oscillating motion of
the strainer.
As it is frequently necessary to remove the strainer from the pulp vat for the
purpose of cleansing or changing the strainer, we make the end of the vat with an
opening preferably large enough to allow the strainer to be drawn out longitudinally
through it, and we close this opening with a plate bolted to the side of the vat and
in which is formed a bearing carrying that end of the strainer shaft. This bearing
is preferably provided with brasses which can be set up to compensate for wear and
tear by means of set screws.
When stuffing boxes and glands are used for the strainer shaft to pass through in
order to prevent the escape of water from the vat past the shaft, they are liable to
produce considerable friction which is prejudicial to the production of the necessary
rapid oscillating motion of the shaft and strainer, besides which some of the
lubricating material is liable to find its way into the pulp vat. To obviate these
inconveniences we dispense with stuffing boxes and glands altogether and employ
instead thereof short indiarubber or other suitable flexible impervious sleeves
secured at one end to a boss or flange on the end of the vat, and at the other end
on a boss or flange on the shaft or on the end of the strainer by means of clamping
hoops. The flexibility of this sleeve allows the strainer to oscillate to and fro
without producing sufficient friction to interfere with that oscillating motion while
it prevents the access of the water in the pulp vat to the bearing and the escape of
the lubricant from the latter into the pulp vat. Instead of making the radial
partitions or fans flat as shown and described in the Specification of the aforesaid
English Patent we sometimes make them concave on both sides whereby we obtain
a better effect than with plain radial partitions or fans. We sometimes dispense with
outlet connections such as those herein before described and we employ instead thereof
an open topped chamber formed with or secured at the end of the strainer. This
chamber is in direct communication with the interior of the strainer and is carried
up above the level of the pulp in the pulp vat and oscillates with the strainer. A
pipe dips into the strained pulp which passes into this chamber from the strainer
and either draws off the same by syphon action or by the suction of a pump.
The necessary rapid oscillating motion is imparted to the strainer shaft and
consequently to the strainer by a crank arm fixed on the said shaft, which may be
driven by means of a connecting rod and crank plate mounted on a driving shaft.
In order to provide means for varying at pleasure the amount of oscillation
imparted to the strainer, we vary the throw of the crank, by which such oscillation
is imparted to the strainer, by mounting it on or forming it with a plate which is
adapted to slide on the crank disc to or from the centre and to be secured in place
by suitable clamping screws. We sometimes apply the driving gear to both ends
of the strainer shaft instead of to one end only and we prefer to employ a separate
driving shaft and gear for each strainer of a series instead of driving a number of
strainers from one crank or eccentric shaft as in our aforesaid former Patent.
Dated this 13th day of May 1892.

page_text: COMPLETE SPECIFICATION.
Improvements in Straining Apparatus for Straining Paper Pulp and
other similar materials.
We, FRANK LIONEL ROECKNER, of Two Water's Mill, Boxmoor, in the County
of Hertford, and RAMSEY LLEWELLYN ROECKNER, of 15 St. Lawrence Road,
North Kensington, in the County of Middlesex, Paper Makers, do hereby declare
the nature of the said invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying two sheets of drawings and to
the letters and figures marked thereon, that is to say :-
This invention relates more especially to straining apparatus of the kind described
in the Specification of an English Patent No. 7932 granted to Carl Heinrich
Roeckner and Frank Lionel Roeckner and dated 30th June 1885.
The strainers described in the above mentioned Specification are of cylindrical
form, contained in the pulp vat and made to oscillate through a small arc more or
less rapidly on their axes; they are generally closed at one end, and they open at
the other end into a vat where the strained pulp is received. It is obviously
necessary to connect the strainers with the vat for receiving the strained pulp by a
joint so arranged that while no pulp can pass to the latter vat without passing through
the strainers, the latter shall be free to perform their oscillatory motions. This is
effected, according to the aforesaid Specification, by means of indiarubber or other
suitable packing round the end of the strainer. It is found in practice that this
form of joint wears out somewhat rapidly and is expensive to renew, and one of the
objects of the present invention is to produce a joint which will fulfil the desired
conditions and will be more durable and less expensive to renew than the one above
referred to.
The drawings hereto annexed illustrate one of a series of vats, each containing a
cylindrical oscillating strainer of the kind above referred to and having our various
improvements applied thereto.
Figure 1 is an end elevation of such a vat, Figure 2 a plan, and Figure 3 a
sectional side elevation of same.
Figure 4 is a transverse section, to a larger scale than the other figures, of the
cylindrical strainer.
Figures 5, 6 and 7 are respectively a plan, partial longitudinal section, and end
sectional elevation, of a vat and strainer of modified construction.
A is the pulp vat, B the strainer which may be of cylindrical form as shown, or,
if preferred, of prismatic, barrel-shaped, or other suitable form, either plain or
corrugated, mounted on a partition or fan B' and shaft C, one end of which shaft'
passes through a bearing at one end of the vat A and the other end of which
passes through an opening E in the other end of the vat and is carried by a
bearing F in the outlet passage G which conveys the strained pulp to the paper
machine or elsewhere. The necessary rapid oscillating motion is imparted to the
strainer shaft C and consequently to the strainer B by the crank arm H fixed on
the shaft C, the connecting rod I and crank plate J mounted on a driving shaft K
revolving in bearings K¹ and having mounted on it the fly wheel K and cone
pulley K by which the speed of oscillation of the strainer B can be varied within
certain limits.
For the purpose of our improved joint, instead of leaving the outlet of the
strainer B of the full diameter of the strainer cylinder as heretofore, we make it
considerably smaller by contracting it with a conical or other suitably shaped
adjutage L, and we then connect this contracted opening with the opening E at the

page_text: end of the pulp vat A by means of a piece of indiarubber or other suitable pipe or
hose M which is sufficiently flexible to allow of the oscillating motion of the
strainer B on its axis without unduly straining the said pipe M by the twisting
action incidental to that motion.
The connecting pipe or hose M may be of any suitable section, and plain or
corrugated and strengthened with wire internally, or externally, or not, as may be
required; or it may be twisted in a manner similar to that employed as the closing
means of certain kinds of indiarubber tobacco pouches for example but of course
not sufficiently twisted in that way to reduce the area of the passage through it
below what is necessary for the passage of the required quantity of strained
material.
The said pipe M may be secured on to the nozzle of the adjutage L and on to
the flange N surrounding the opening E through the end of the vat so as to prevent
the passage of pulp except through the slits of the strainer by being bound round
with wire, but preferably by means of clamping hoops P tightened up by clamping
screws Q.
According to another arrangement, the outlet opening is placed at a suitable point
in the circumference of the strainer (which may be of cylindrical, prismatic, barrel-
shaped or other suitable form either plain or corrugated) as at R, and we connect
such outlet opening with a corresponding opening in the side or bottom of the vat,
as at S for example, by means of a piece of flexible pipe, or by a connection in the
form of a bellows, as shown at T for example, which has plenty of lateral flexibility
to enable the strainer B to make its oscillatory motions without overstraining such
connection. When this last described outlet connection is employed, both ends of
the strainer may be closed, or an outlet from the end of the strainer and another
from some part of the circumference may be employed at the same time.
We sometimes employ an outlet at each end of the strainer B and sometimes
several outlets from the circumference thereof with or without the outlet or outlets
at the end or ends. The greater the number of outlets employed, the smaller may
be the diameter of the flexible outlet pipes, and thereby the smaller will be the
wear and tear thereof due to the bending or twisting by the oscillating motion of
the strainer.
As it is frequently necessary to remove the strainer B from the pulp vat A for
the purpose of cleansing or changing the strainer, we make the end of the vat with
an opening A preferably large enough to allow the strainer B to be drawn out
longitudinally through it, and we close this opening with a plate A bolted to the
side of the vat and in which is formed a bearing D carrying that end of the strainer
shaft C. This bearing is preferably provided with brasses which can be set up to
compensate for wear and tear by means of set screws A³. When it is required to
remove a strainer, the joint pipes M T are disconnected, the connecting rod I
uncoupled from the arm H, and the plate A' unbolted; the latter and the strainer,
with its shaft, can then be drawn out of the vat through the opening A'and cleaned
or replaced with another.
When stuffing boxes and glands are used for the strainer shaft C to pass through
in order to prevent the escape of water from the vat past the shaft, they are liable
to produce considerable friction which is prejudicial to the production of the
necessary rapid oscillating motion of the shaft and strainer, besides which some of
the lubricating material is liable to find its way into the pulp vat. To obviate
these inconveniences, we dispense with stuffing boxes and glands altogether and
employ instead thereof short indiarubber or other suitable flexible impervious
sleeves in the manner shown in Figures 2 and 3, where U represents such a flexible
water and oil proof cylindrical sleeve secured at one end to a boss or flange U¹ on
the end of the vat, and at the other end on a boss or flange U2 on the shaft or on
the end of the strainer by means of clamping hoops U³. The flexibility of this
sleeve U allows the strainer to oscillate to and fro in a manner similar to the pipe M
at the outlet joint in Figures 2 and 3 without producing sufficient friction to

page_text: interfere with that oscillating motion while it prevents the access of the water in
the pulp vat to the bearing D and the escape of the lubricant from the latter into
the pulp vat. A similar arrangement is shown at the other end of the shaft
where Vis an elastic sleeve secured at one end to the shaft C and at the other to
a boss or flange on the inner end of the bearing F.
The transverse section of a strainer, Figure 4, shows an improved form of the
radial partitions or fans employed in strainers of the kind described in our aforesaid
former Patent. Instead of making such partitions or fans flat, we sometimes make
them concave on both sides as shown at B* in that figure, whereby we obtain a
better effect than with plain radial partitions or fans.
In the arrangement shown in Figures 5, 6 and 7 we dispense with outlet con-
nections such as those shown at M and T in Figures 2 and 3 and we employ instead
thereof an open topped chamber W formed with or secured at the end of the
strainer B. This chamber is in direct communication with the interior of the
strainer and is carried up above the level of the pulp in the pulp vat A and oscillates
with the strainer. A pipe W dips into the strained pulp which passes into this
chamber from the strainer and either draws off the same by syphon action or by
the suction of a pump.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
First In oscillating cylindrical or prismatic strainers, the improved outlet
arrangement which consists of a reducing adjutage on the end of the strainer and
a flexible pipe one end of which surrounds and is connected to the reduced nozzle
of the said adjutage and at the other end surrounds and is connected to the outlet
from the vat in which the strainer is placed, as hereinbefore described and
illustrated in Figures 1 and 2 of the drawings.
Second In oscillating cylindrical or prismatic strainers, the improved outlet
arrangement which consists of an outlet opening at the circumference of the strainer
and a corresponding outlet opening in the vat, such openings being connected
together by a flexible pipe or bellows as hereinbefore described, and illustrated in
Figures 1, 2 and 3 of the drawings.
Third Constructing the pulp vats containing oscillating cylindrical prismatic
strainers with an opening at the end and a cover plate whereby the strainer and
its shaft can easily be removed as hereinbefore described and illustrated in Figures 1, 2
and 3 of the drawings.
Fourth In connection with oscillating cylindrical or prismatic strainers, the
improved means of making a water and oil tight connection between the shaft and
its bearing which consists of a sleeve of indiarubber or other suitable flexible
impervious material secured liquid-tight at one end round the bearing and at the
other end round the oscillating shaft as hereinbefore described, and illustrated in
Figures 2 and 3 of the drawings.
Fifth In oscillating cylindrical or prismatic strainers, constructing the partitions
or fans of curved form on both sides as hereinbefore described, and illustrated in
Figure 4 of the drawings.
Sixth-As a means of drawing off the strained material from the interior of an
oscillating cylindrical or prismatic strainer, the use of an open topped chamber at
the end of and oscillating with the strainer, and a syphon or suction pipe dipping
into such chamber, as hereinbefore described, and illustrated in Figures 5, 6 and 7
of the drawings.
Seventh-The improved straining apparatus consisting of the cylindrical or
prismatic strainer B, flexible outlet tubes M or T or both, flexible water and oil
tight connections UV between the oscillating shaft and its bearings, and the
removable end cover plate A' carrying one of the bearings of the strainer shaft
and closing an opening A¹ in the end of the vat for the purpose of facilitating the

page_text: changing of the strainer, combined, arranged and operating as hereinbefore
described, and illustrated in Figures 1, 2 and 3 of the drawings.
Dated this 11th day of February 1893.
F. L. ROECKNER,
R. L. ROECKNER,
Per W. H. Beck,
115, Cannon Street, London, E.C., Agent.