IMPROVEMENTS IN THE CONSTRUCTION OF CENTRIFUGAL DRAINING AND SUBSIDING MACHINERY, AND IN THE METHODS OF AND APPARATUS FOR SUPPORTING AND DRIVING THE SAME
Year: 1877

page_text: LETTERS PATENT to James Bingham Alliott, of Radford, in the County of
Nottingham, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF
CENTRIFUGAL DRAINING AND SUBSIDING MACHINERY, AND IN THE METHODS
OF AND APPARATUS FOR SUPPORTING AND DRIVING THE SAME."
Sealed the 6th April 1877, and dated the 20th January 1877.
PROVISIONAL SPECIFICATION left by the said James Bingham Alliott at
the Office of the Commissioners of Patents on the 20th January 1877.
JAMES BINGHAM ALLIOTT, of Radford, in the County of Nottingham. "IMPROVE-
MENTS IN THE CONSTRUCTION OF CENTRIFUGAL DRAINING AND SUBSIDING
MACHINERY, AND IN THE METHODS OF AND APPARATUS FOR SUPPORTING AND
DRIVING THE SAME."
My improvements in the construction of centrifugal draining and subsiding
machines apply in the first instance to machines of this class, having the axis hori-
zontal.
In these machines I support the horizontal shaft carrying one or more of the
draining or subsiding vessels by means of bearings secured to rigid arms which I
usually make of metal. At the end of each of these arms furthest removed from the
bearing I form a foot or flange which I attach to a rigid support or standard by the
intervention of india-rubber or other yielding buffers, which while they allow a con-
siderable range of movement whether vertically or horizontally to the bearing at
the further end of the arm, nevertheless to offer increasing resistance to any
departure from its normal position.
To the feet or flanges above mentioned may be fastened bearings carrying the
countershaft, keyed upon which is a pulley for driving the shaft carrying the drain-
ing or subsiding vessels. As these two shafts are maintained at a constant distance
apart, no difference in the tension of the belt will arise from the swinging or vibra-
tion of the draining or subsiding cylinders, while if the countershaft itself be driven
from a shaft on or near the same horizontal level, the changes in its position will
not appreciably alter the tension of the belt driving it.
Sometimes I fix two or more draining or subsiding vessels upon such a horizontal
shaft, especially when I desire to make these vessels of the form of a double saucer
with the lips or edges in contact, and wish them to discharge their solid contents by

page_text: separating their lips or edges. In this case I key the outer half of each cylinder
fast upon the shaft while I attach the inner halves of the two cylinders together
and allow them to slide together upon the shaft, so that when one cylinder is closed
at the edges the other is open, and, vice versa. In order to actuate the sliding
halves of the vessels I make the shaft hollow and introduce a rod into it. A cotter
passes through this rod ond through a slot in the hollow shaft and into the boss
connecting the two moveable halves of the cylinders. This rod I actuate by means
of a screw working in a fixed bearing attached to the bearing of the shaft and
worked by a hand wheel. As the rod is forced into or withdrawn from the hollow
shaft, the movable parts of the cylinders being fast to the cottar already described,
slide along the shaft backwards and forwards, opening one of the cylinders and
closing the other. The boss connecting these movable parts may, if desired, be
used as the driving pulley of the apparatus.
It will be obvious that by very slight modification this arrangement would be
equally applicable for opening and closing a single cylinder.
In order to avoid the difficulty of making a joint in such machines by simply
bringing the edges of the lips in contact, I arrange an angle iron attached to the one
lip at its periphery and forming a cylinder or preferably a truncated cone fitting
over and projecting beyond the other lip. If the cylinder be for subsiding, the
angle iron may be lined with a ring or pad of india-rubber which, when the two
halves of the draining or subsiding vessel are pressed together, shall be squeezed
between the two lips, and prevented from expanding outwards by the angle iron
ring.
It.is evident that the pressure exerted under the influence of centrifugal force by
the material within the vessel will press the india-rubber pad or ring against both
lips or edges of the vessel, and also against the angle iron ring, and so make a more
secure joint. The keeping together of the edges or lips of a subsiding or draining
vessel such as just described is rendered difficult by the fact that the action of the
material within the vessel under the influence of centrifugul force tends powerfully
to, as it were, wedge these edges apart. In order to avoid this I sometimes attach
both halves of the vessel firmly together, but having their edges, say, two inches
apart, or at such a distance apart as is required for the ready discharge of the
drained or subsided material.
The space between the two lips I close by a ring of angle iron bored to fit over
the edges of the lips which are truly turned. This angle iron ring may be bored of
a cylindrical, or as is generally preferable of a conical form, so as to allow of
compensation for wear without the tightness of the joint being sensibly affected.
This angle iron ring I attach by means of stiff rods or arms to a boss fitting on to
the shaft to which the draining or subsiding vessel is attached, and capable of
sliding backwards and forwards upon the shaft. The motion necessary for moving
this boss, together with the angle iron ring it holds (so as to either open or close the
space left between the lips or edges of the draining or subsiding vessel) may either
be communicated by means of apparatus similar to that already described for
nctuating the movable halves of draining or subsiding vessels which are closed by
bringing the edges of the saucer-shaped vessels into contact, and opened by sepa-
rating the edges or by a suitable arrangement of levers.
My further improvements in the construction of centrifugal machines refer to
arrangements chiefly intended to effect the more easy removal of the drained (or
subsided) material therefrom. Around a central shaft I arrange a number of vessels
into which the material to be treated is put. Each of these vessels is suspended on
trunions carried by the shaft at a point slightly above its centre of gravity when
loaded, and I prefer to arrange an even number of vessels around the shaft so that
the strain of each one when in motion may be so far as possible counterbalanced by
the strain of the one directly opposite to it on the other side of the shaft. The
shaft itself I prefer to fix in elastic bearings, or else I suspend the whole machine.
The trunions which hold each of the vessels are firmly secured to the revolving
shaft. When the machine is at rest that part of each vessel which is lowest and

page_text: which is closed, thus forming a "bottom," is of somewhat smaller dimensions than
that part which is uppermost, or the "top" which is open.
In machines used for draining, the "bottom" of each vessel is perforated, and in
both draining and subsiding machines almost the whole of the bottom or of a false
bottom resting on it is capable of being forced inwards. When working the
machine for draining purposes, each of the vessels is first filled with the material to
be operated upon, and then the machine is put into motion; as its speed increases
the position of the centre of gravity of each vessel, and its contents in relation to
the trunnions holding it, causes the vessel under the action of centrifugal force
gradually to incline until its perforated "bottom" is the part furthest from the
centre around which the vessels revolve. Thus the moisture contained in the
material is drained away through the "bottom" and thrown outwards. When the
material is sufficiently dry the machine is stopped and the vessels again take their
original position bottom downwards.
"
In order to remove the drained material they are turned in the trunnions till
they are bottom uppermost. The loose bottom or false bottom is then forced in-
wards (but prevented by a suitable stop from dropping) when the contents are
loosened and dropping out of the enlarged "top" of the vessel may be collected
below.
When vessels of this description are used for subsiding purposes they are emptied
in a similar way, though the method of filling may be different to suit the different
purpose to which the apparatus is applied and though the "bottoms" are not per-
forated.
Other improvements in centrifugal machines consist in the method of suspending
the working parts of those having the axis vertical or nearly so. In these machines
I provide the substantial bracket (into which are fixed the upper and lower
bearings of the rotating shaft to which the draining or subsiding vessel is attached)
with three or more arms or projections at its lower part. These arms project
through the casing which catches the drainings or overflow, and to them I attach
suspension rods which I prefer to pass through snugs lined with india-rubber or
other yielding material on the lower part of the casing, while I attach them above
to snugs on the upper part of the casing. Thus the machine may be said to be
self-contained, its moving parts being suspended within the casing which itself is
fixed.
Sometimes I drive such a centrifugal machine by an engine of short stroke and of
the following construction :-To one of the arms or projections of the bracket carry-
ing the shaft and rotating vessel I firmly attach a single-acting steam cylinder,
having its outer end closed and its inner end (that nearest to the rotating shaft
which is duly provided with a crank so that it forms the crank shaft of the engine)
quite open. I provide this steam cylinder with a steam port at or near its outer
end, together with a suitable valve (preferably of the piston type and worked by an
excentric) for the distribution of steam.
Within the steam cylinder I arrange a long hollow piston provided with suitable
packing, and like the cylinder itself, closed or solid at its outer end and open at its
inner end. Since there is no cover to the inner end of the steam cylinder, the
piston forms the only obstacle to the escape of steam in this direction.
I do not make use of any piston rod, the piston being sufficiently long to render
the use of additional guides unnecessary, and I attach the connecting rod to the
piston as near as possible to its outer end. This connection I make with spring
steel which gives the necessary flexibility, while avoiding the use of rubbing or
wearing parts. attach the excentric rod to the valve in like manner within a long
hollow piston (a continuation of the metal forming the piston valve) which also is
long enough to enable a guide to be dispensed with. It is evident that an engine
thus arranged will be single acting, actuated by the pressure of steam on the outer
side only of its piston, and that it will make as many strokes per minute as the
rotating vessel makes revolutions, since the crank of the engine is formed on the
rotating shaft.

page_text: It is obvious that an engine, substantially as described, may be used for driving
other forms of centrifugal machines than that to which its application is described.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Bingham Alliott in the Great Seal Patent Office on the 19th
July 1877.
JAMES BINGHAM ALLIOTT, of Radford, in the County of Nottingham. "IMPROVE-
MENTS IN THE CONSTRUCTION of CENTRIFUGAL DRAINING AND SUBSIDING
MACHINERY, AND IN THE METHODS OF AND APPARATUS FOR SUPPORTING AND
DRIVING THE SAME."
My improvements in the construction of centrifugal draining and subsiding
machines apply in the first instance to machines of this class having the axis hori-
zontal, as represented in vertical section at Fig. 1, and end elevation at Fig. 2 in
the annexed Drawings.
In these machines I support the horizontal shaft A (carrying one or more of the
draining or subsiding vessels) by means of bearings B secured to the rigid arms C,
which I usually make of metal. At the end of each of these arms furthest removed
from the bearing I form a bracket or flange D which I attach to a rigid support or
standard E by the intervention of india-rubber or other yielding buffers F, F, above
above and below, which while they allow a considerable range of movement, whether
vertically or horizontally to the bearings B at the further end of the arms C,
nevertheless offer increasing resistance to any departure from its normal position.
To the brackets or flange D above mentioned may be fastened bearings G carry-
ing the countershaft H, upon which is a pulley I for driving the shaft A, carrying
the draining or subsiding vessels by means of the belt K. As these two shafts A
& H are maintained at a constant distance apart no difference in the tension of
the belt K will arise from the swinging or vibration of the draining or subsiding
cylinders, while if the countershaft H itself be driven by a strap passing round the
pulley L from a shaft on or near the same horizontal level, the changes in its position
will not appreciably alter the tension of the belt driving it.
Sometimes (as shown at Fig. 1) I fix two or more draining or subsiding
vessels M and N upon such a horizontal shaft A, especially when I desire to make
these vessels of the form of a double saucer with the lips or edges in contact (as
shown above the axle A in Fig. 1) and wish them to discharge their solid contents
by separating their lips or edges m, m, and n, n. In this case I key the outer
half M' and N¹ of each cylinder fast upon the shaft, while I attach the inner halves
M and N of the two cylinders together and allow them to slide together upon the
shaft A, so that when one cylinder is closed at the edges, as shown at the right hand
of Fig. 1, the other is open, as shown at the left hand of the same Figure, and
vice versa. In order to actuate the sliding halves M, N, of the vessels I make the
shaft A hollow as at A¹, and introduce a rod O into it. A cotter P passes through
this rod and through a slot Q in the hollow shaft, and into the boss or pulley R,
connecting the two movable halves M and N of the cylinders. This rod O I actuate
by means of a screw S working in a fixed bearing T attached to the bearing B of
the shaft A and worked by a hand wheel U. As the rod O is forced into or with-
drawn from the hollow shaft A¹, the moveable parts M, N, of the cylinders being fast
to the cotter P already described, slide along the shaft backwards and forwards,
opening one of the cylinders and closing the other. The boss R connecting these
moveable parts may, if desired, be used (as shown at Fig. 1) as the driving pulley of
the apparatus.
It will be obvious that by very slight modifications this arrangement would be
equally applicable for opening and closing a single cylinder.
In order to avoid the difficulty of making a joint in such machines, by simply

page_text: bringing the edges of the lips into contact (as shown above the axle at Fig. 1) I
sometimes arrange an angle iron m" and n" attached to the one lip m¹ and n¹ at
its periphery, and forming a cylinder, or preferably a truncated cone fitting over and
projecting beyond the other lip m or n when the vessel is closed, as shown below
the axle A in Fig. 1. If the cylinder be for subsiding, the angle iron may be lined
with a ring or pad of india-rubber m, n, which when the two halves of the
draining or subsiding vessel are pressed together (as shown at the right hand of
Fig. 1) shall be squeezed between the two lips n, n', and prevented from expanding.
outwards by the angle iron ring n¹¹.
It is evident that the pressure exerted under the influence of centrifugal force by
the material within the vessel will press the india-rubber pad or ring n¹¹ against
both lips or edges n and n¹ of the vessel, and also against the angle iron ring n",
and so make a more secure joint. The keeping together of the edges or lips of a
subsiding or draining vessel such as just described is rendered difficult by the fact
that the action of the material within the vessel under the influence of centrifugal
force tends powerfully to, as it were, wedge these edges apart. In order to avoid
this I sometimes (as shown at Fig. 3) attach both halves M, M', and N¹, N, of the
vessels firmly together by brackets V or otherwise, leaving their edges, say, two
inches apart, or at such a distance apart as is required for the ready discharge of
the drained or subsided material.
The space between the two lips I close by a ring of angle iron W bored to fit
over the edges of the lips, which are truly turned. This angle iron ring W may be
bored of a cylindrical, or as is generally preferable, of a conical form, so as to allow
of compensation for wear without the tightness of the joint being sensibly affected.
This angle iron ring W I attach by means of stiff rods or arms X to the boss R,
fitting on to the shaft A to which the draining or subsiding vessels are attached
and capable of sliding backwards and forwards upon the shaft. The motion neces-
sary for moving the boss, together with the angle iron ring W which it holds (so as
to either open or close the space left between the lips or edges of the draining or
subsiding vessels) may either be communicated by means of apparatus similar to
that already described for actuating the moveable halves of draining or subsiding
vessels which are closed by bringing the edges of the saucer-shaped vessels into
contact, and opened by separating these edges, or by a similar arrangement of
levers.
My further improvements in the construction of centrifugal machines refer to
arrangements chiefly intended to effect the more easy removal of the drained (or
subsided) material therefrom, and are represented in section at Fig. 4, and plan view
at Fig. 5. Around a central shaft A I arrange a number of vessels B into which
the material to be treated is put. Each of these vessels is suspended on trunnions C
(carried by the plate D fixed on the shaft A) at a point slightly above its centre of
gravity when loaded, and I prefer to arrange an even number of vessels B around
the shaft A, so that the strain of each one when in motion may be, so far as possible,
counterbalanced by the strain of the one directly opposite to it on the other side of
the shaft. The shaft A itself I prefer to fix in elastic bearings E, E, or else I suspend
the whole machine. The trunnions C which hold each of the vessels B are firmly
secured to the revolving shaft A by the plate D. When the machine is at rest, that
part of each vessel B, which is lowest and which is closed, thus forming a "bottom "b,
is of somewhat smaller diameter than that part b¹ which is uppermost, or the "top,"
and which is open.
In machines used for draining the "bottom" b of each vessel is perforated, and
in both draining and subsiding machines almost the whole of the bottom 6 or of a
false bottom resting on it is capable of being forced inwards. When working the
machine for draining purposes each of the vessels is first filled with the material to
be operated upon, and then the machine is put into motion; as its speed increases
the position of the centre of gravity of each vessel B and its contents in relation to
the trunnions C holding it causes the vessel under the action of the centrifugal
force gradually to incline until its perforated "bottom" is the part furthest from the

page_text: centre around which the vessels revolve, as shown by dotted lines to the left hand
of Fig. 4; thus the moisture contained in the material is drained away through the
bottom and thrown outwards. When the material is sufficiently dry the machine
is stopped and the vessels again take their original position bottom downwards.
In order to remove the drained material they are turned in the trunnions until they
are "bottom" uppermost, as shown by dotted lines at the right hand in Fig. 4. The
loose bottom or false bottom is then forced inwards by the knob 6" (but prevented by
the cross bar 611 from dropping) when the contents are loosened, and dropping out
of the enlarged "top" of the vessel may be collected below in a cart or other
receptacle I.
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When vessels of this description are used for subsiding purposes they are emptied
in a similar way, though the method of filling may be different to suit the different
purpose to which the apparatus is applied, and though the "bottoms
perforated.
Other improvements in centrifugal machines consist in the method of suspending
the working parts of those having the axis vertical or nearly so, as shown in
vertical section at Fig. 6, and horizontal section Fig. 7. In these machines I
provide the substantial bracket A (into which are fixed the upper and lower bearings
of the rotating shaft B to which the draining or subsiding vessel C is attached with
three or more arms or projections D at its lower part. These arms project through
the casing E which catches the drainings or overflow, and to them I attach suspension
rods F which I prefer to pass through snugs lined with india-rubber or other
yielding material in the lower part of the casing E, while I attach them above to
snugs on the upper part of the casing; thus the machine may be said to be self-
contained, its moving parts being suspended within the casing E, which itself is
fixed.
Sometimes I drive such a centrifugal machine by an engine of short stroke and
of the following construction:-To one of the arms or projections of the bracket
carrying the shaft and rotating vessel I firmly attach a single acting steam cylinder G
having its outer end G¹ closed, and its inner end (that nearest to the rotating shaft
which is duly provided with a crank so that it forms the crank shaft of the engine)
quite open; I provide this steam cylinder with a steam port at or near its outer end,
together with a suitable valve (preferably) of the piston type, and worked by an
excentric for the distribution of steam.
Within the steam cylinder G I arrange a long hollow piston H provided with
suitable packing, and like the cylinder itself closed or solid at its outer end and
open at its inner end. Since there is no cover to the inner end of the steam
cylinder G the piston H forms the only obstacle to the escape of steam in this
direction.
I do not make use of any piston rod, the piston being sufficiently long to render
the use of additional guides unnecessary, and I attach the connecting rod I to the
piston H as near as possible to its outer end. This connection I make preferably
with spring steel K which gives the necessary flexibility; while avoiding the use of
rubbing or wearing parts I attach the excentric rod L to the valve in like manner
within a long hollow piston, a continuation of the metal forming the piston valve
which also is long enough to enable a guide to be dispensed with. It is evident
that an engine thus arranged will be single acting, actuated by the pressure of
steam on the outer side only of its piston, and that it will make as many strokes
per minute as the rotating vessel makes revolutions since the crank of the engine is
formed on the rotating shaft A.
It is obvious that an engine constructed substantially as described may be used
for driving other forms of centrifugal machines than that to which its application is
described.
Having now described the nature and object of my said Invention, together with
the manner in which the same is to be or may be performed or carried into practical
effect, I wish it to be understood that I claim as my Invention,-
Firstly. The general arrangements, substantially as shown and described, for

page_text: supporting centrifugal, draining, or subsiding machines (having their axes horizontal
or nearly so) in elastic bearings.
Secondly. The method, substantially as shown and described, of opening and
closing such centrifugal draining or subsiding vessels as have the form of a double
saucer, and discharge their solid contents by separating the edges of the saucer.
Thirdly. The arrangement, substantially as shown and described, for facilitating
the making of the joint around the edges of such vessel.
Fourthly. The arrangement, substantially as shown and described, of such
centrifugal, draining, and subsiding vessels having both halves of the saucer firmly
fixed with their lips or edges at such a distance apart as will allow of free egress for
the solid contents of the vessel.
Fifthly. The general arrangement and construction of centrifugal, draining, or
subsiding apparatus, substantially as described, and as shown in Figs. 4 and 5.
Sixthly. The general arrangement and construction of centrifugal, draining, or
subsiding apparatus having the moving parts suspended from and within the casing,
substantially as described and shown in Fig. 6 and 7.
Seventhly. The general arrangement of engine constructed substantially as
described, with reference to the same Figures for driving centrifugal apparatus.
In witness whereof, I, the said James Bingham Alliott, have hereunto set
my hand and seal, this Seventeenth day of July, in the year of our Lord
One thousand eight hundred and seventy-seven.
JAMES BINGHAM ALLIOTT. (L.S.)