A NEW AND USEFUL IMPROVEMENT IN PROCESSES OF SEPARATING STARCH
Year: 1883

page_text: "
LETTERS PATENT to Sydney Pitt of Sutton in the County of Surrey for an
Invention of "A NEW AND USEFUL IMPROVEMENT IN PROCESSES OF SEPARATING
STARCH Communicated to him from abroad by Teile Henry Müller and
Jacob W. de Castro both of the City County and State of New York United
States of America,
COMPLETE SPECIFICATION filed by the said Sydney Pitt at the Office of
the Commissioners of Patents on the 27th February 1883.
IMPROVEMENT IN PROCESSES OF SEPARATING STARCH
USEFUL
SYDNEY PITT of Sutton in the County of Surrey "A NEW AND
" Communicated to me
from abroad by Teile Henry Müller and Jacob. W. De Castro both of the City,
County and State of New York United States of America
This invention relates to improved processes and apparatus for separating bodies
of different specific gravities, especially starch from starch water. The apparatuses
however are applicable to many other processes beside that herein described.
It is proposed by this improved process to separate the starch and gluten con-
tained in starch water, depositing the starch in a suitable basket or receptacle, and
continuously removing the gluten. After the basket or chamber has been filled
with the deposited starch, it is readily removed by washing or through suitable
openings in the bottom. In this process the starch water is caused to flow into a
revolving centrifugal basket, and by means of the centrifugal force and difference
in specific gravity the gluten is driven to the inside of the basket forming an inner
surface there, while the starch forms an outer ring toward the periphery of the
basket. A removing apparatus continually removes the gluten as it is deposited
thereby leaving in the basket a deposit of pure starch which may be removed by
any suitable means..
The invention will be readily understood from the accompanying Drawings in
which Figure 1 represents a plan view of the entire apparatus: Figure 2 a section
through the basket of the centrifugal machine, and the removing apparatus:
Figure 3 a detailed view of the outer or removing tube, being a section through.
the line xx Figure 2; Figure 4 a detailed view of the apparatus for adjusting the

page_text: .
cutter; Figure 5 a plan view of apparatus for determining the rate of motion of
the cutter; Figure 6 a view at right angles to Figure 5, partly in section.
Figures 7, 8, 9, 10 and 11 details of the reversing and adjusting apparatus shown
in Figure 5.
The apparatus consists generally of a centrifugal machine; in the form shown
one open at the top is used. This basket is driven from below and is known
generally as an under-driven machine. This basket may be of any suitable con-
struction and may be arranged as a hanging basket if preferred. An adjustable
cutter or removing apparatus is provided, which, after the bodies have been
separated in the basket in the manner to be described by the difference of specific
gravity and the centrifugal force excited upon them in the machine will con-
tinuously remove that one of said bodies which is deposited toward the centre of
the basket or on the inside thereof. The invention principally relates to the
method of operating this cutter; and to its introduction within a centrifugal
machine.
In the drawings similar letters refer to similar parts. A represents the basket
of the centrifugal machine driven from the power shaft C by belt b. Attached to
the support of the basket is the cutter tube B which is adjustable toward and from
the periphery of the basket. The shape of this cutter is shown in section in
Figure 3, but I do not limit myself to this form. The cutter is supported upon the
slide p which is longitudinally adjustable on the frame or bed D. This slide as
shown is arranged to operate in the dovetailed grooves as shown in Figure 4. By
moving the slide inward and outward the position of the cutting edge of B with
reference to the periphery of the basket is determined. The position of the slide p
is determined by the screws which engages with the nut t attached to and moving
with the slide. The screw 8 is supported in the frame B and its longitudinal
motion is prevented by the gear wheel v and collar y. By rotating the wheel v in
one direction the slide and the cutter will be forced inward toward the centre of
the basket until its motion is arrested by the stop r. It motion outward would
be arrested by the collar y. In practical operation it is necessary that the cutter
should be moved both inward and outward and it is exceedingly desirable that its
velocity of movement in both directions should be exactly determinable and the
apparatus shown is a very convenient and efficacious means of carrying out this
design. This apparatus is shown in detail in Figures 5, 6, 7, 8, 9, 10 and 11. It
consists generally of a power shaft c driven by belt a from the main shaft C.
Upon this shaft are two friction discs e e¹, the bearing surfaces of which are
preferably made of leather, though other suitable material might be employed.
These discs are clearly shown in Figure 5 and their position longitudinally upon
the shaft C is readily determined by securing them upon said shaft and locking
them when located by lock nuts o. These discs engage with the metallic disc g
which can be brought in contact with either one or the other of them at will. This
disc g is mounted upon a shaft F supported in a frame h. The frame h is pivotted
at one end on the fixed fulcrum j, while its other end is held against the slide rest
by the nuts i, the bolts of which pass through slots in the adjustable frame. It
will thus be apparent that by swinging the frame h about the pivot j either one or
the other of the discs e e¹ can be brought in contact with the discs g at will. The
position of this frame h is determinable by the eccentric l. This eccentric is con-
nected by link L to the frame h, and by means of it that frame can be swung in
either direction. Of course many other devices might be used, but the one here
shown is very convenient, for by means of it the disc g can be caused to revolve in
either direction and its motion in either direction can be independently regulated
so that it may move faster when moving in one direction that when it moves in
the other, which, under certain circumstances is desirable in the practical operation
of the apparatus. It is preferred to support the shaft C at its end by means of the
thrust rings shown in Figures 7, 8, and 9. The upper half of the bearing n is
removable to allow the placing of these rings in position in the well known
manner.

page_text: Ine operation or the apparatus can now be readily understood: Supposing it be
desired to separate starch water containing starch and gluten so as to deposit the
starch in the machine and remove the gluten and water therefrom, the machine
may be operated as follows: The basket is put in motion and the eccentric / is so
5 located that neither wheel e nor e' comes in contact with the disc g which con-
sequently remains stationary; a suitable amount of liquid is then allowed to flow
into the bottom of the basket by means of a suitable tube, thence it goes directly
to the periphery of the basket, and there forms a hollow cylinder, the starch
particles going to the outside or against the periphery of the basket, and the
liquid and gluten standing on the inside thereof. The cutter should then be
moved by its feed screw as close as possible to the periphery of the basket and the
starch water should be allowed to flow freely into the basket care being taken to
regulate the feed according to the capacity of the machine. The eccentric is then
so operated as to cause the screw S to be turned in the direction which will cause
the gradual withdrawal of the cutter from the periphery of the basket. The
proper velocity of this movement can be readily determined by experiment by
means of adjusting the friction disc e' to the proper position. The liquid deposited
upon the bottom of the basket will flow rapidly to the edge and then upward upon
the side until it meets the cutter which is located as close as possible to the upper
corner of the basket. During the upward flow of the liquid the larger part of the
starch is deposited partly by centrifugal force direct, and partly by a peculiar
property of the starch globules to be retained by formerly deposited starch surfaces,
while the gluten which is more slippery, is carried along by the current and
removed from the machine by the scraper together with the superfluous liquor
which stands within the starch ring. It will therefore easily be seen that the
speed of the scraper should depend upon the amount of deposit in the machine. As
soon as the basket is filled with pure starch the feed motion of the scraper is
stopped, and the cock closed so as not to admit any more liquor. The scraper is
now turned back so as just to enter the surface of the starch ring and a small
amount of water admitted into the machine. This washes off any gluten or
impurities that may have adhered to the surface of the starch, and the impurities
and the water escape through the scraper, leaving the starch dry and clean. If it.
is desired to remove the starch in a liquid form from the machine the scraper is
now made to move toward the rim of the basket from the axis by throwing the
other friction disc e in contact with the disc g and the starch is washed up by
means of a jet of water issuing from a hose nozzle or other suitable contrivance.
In this operation care must be taken not to admit more water than can be
constantly removed from the basket by the scraper, as any superfluous liquid in
the basket would be the cause of undue oscillations in the apparatus. For
purposes where the starch is to be used dry, it may be removed from the basket
by the same means as are used for removing sugar from similar machines, and the
machine should then be made with openings in the bottom in the well known
way. The gluten and water which are removed from the basket in the practical
operation of this machine can be preserved when it is desired to employ the gluten
for other purposes or to dry the same. Instead of the last apparatus described I
may use the apparatus shown in Figures 16, 17, 18 and 19. In this apparatus the
overflow passes directly through the basket itself. The apparatus will be readily
understood from the accompanying drawings, in which Figure 20 represents a
sectional view through the basket, shewing the tube driving mechanism: Figure 21
a view of the discharge or overflow pipe. Figure 22 an end view of the same.
Figure 23 a bottom view of the same. Figure 24 a plan of the machine showing
the counter-shafts.
C represents the centrifugal basket which may be of any suitable construction.
The liquid to be introduced into this basket may be introduced through any
suitable apparatus, but in the drawings shown it passes through the central
tube H, and then passes to the bottom of the basket through the pipe a a. Two
pipes D' D' project outwardly through the lateral openings through the periphery of

page_text: the basket in which they should fit reasonably tight. The position of the inner
edge of these tubes determines the thickness of the material deposited within the
basket. The motion of these tubes D' D' is determined by the bell-crank
levers b b which are attached by links e to a shifting collar E. The position of
this collar is determined by the lever F supported on the fulcrum G. As the
collar is raised, it is evident that the inner edges of the tube D¹ D' will be moved
outwardly, and as the collar E is depressed the inner edges will be moved inwardly.
The motion of the collar is determined through the lever F by means of the link I
having at its lower end a screw thread K upon which the worm wheel M turns as
a nut. This wheel M is turned by the screw L which screw is itself turned by
the pulley O, when thrown in connection with the clutch P. The pulley O is
driven from the pulley u on shaft S. W represents the overflow connected with
the casing B.
The operation of the apparatus can now be readily understood. The collar E
being raised so that the pipes D'D' project as far as possible, the liquid to be
separated is allowed to fall into the basket, the basket by its revolution causes the
deposit of the solid particles in a ring on the outside of said basket, the liquid
overflowing through pipes D' Ds. As this deposit continues the pipes D' D' are
continually drawn inward by the revolution of the nut M turning on the screw
thread K until the basket is. filled up to its capacity. The deposited material may
be removed in any suitable way.
Another form of apparatus for accomplishing the same result is shown in
Figures 20, 21, 22, 23 and 24. In this apparatus the removable overflow opening
is made in the bottom of a centrifugal basket for the purpose of allowing the
overflow of the liquid to gradually recede from the circumference to the centre
during the deposit of materials such as starch within the basket.
The invention will be readily understood from the accompanying Drawings of
which Figure 16 represents an elevation: Figure 17 a vertical section: Figure 18
plan view of the bottom of the basket: and Figure 19 a view underneath the
basket looking upward. A represents the stand of a centrifugal machine, sup-
porting a basket K of any suitable construction. The bottom of this basket is
made of two plates, one fixed to the basket, and the other lying thereon and
movable thereover. These plates are provided with openings having edges inclined
to each other, or to the radius of the basket in a manner subsequently to be
explained.
As shown, the openings are triangular in shape. Beneath the lower plate is a
pocket or channel P shown in Figures 17 and 19. The fixed opening in the lower
plate is marked de f. The movable opening is marked a b c When these
openings correspond, there will be two openings in the bottom of the basket
approaching near to the periphery. As the movable plate is turned upon the fixed
plate, the point of the opening will gradually recede from the periphery toward
the centre as shown in Figure 18 until finally the opening would be entirely closed.
The mechanism for causing this gradual recession is shown in Figures 16, 17 and 19.
The pulley F is driven from the pulley D on the power shaft B. The lower pulley C
drives a pulley E upon said shaft through a movable clutch. On the spindle S is
fastened the centre V of the bottom of the basket K, which is provided with
bearings for shafts L L on which are immovably fastened the wheels MM. These
wheels M M gear into an opening formed on the hub of the pulley F, and the
wheels N N also fixed upon the shafts of the wheels M M gear into an internal
gear-wheel W, which gear-wheel W is attached to and moves the movable bottom
of the basket. This movable plate as shown in Figure 17 is suspended beneath
the fixed plate, and is provided with pockets P P, beneath the opening d. e. f for
directing the escaping liquid outward into the overflow casing. By turning f
therefore the pockets P and corresponding openings on the valve plate may be
moved with relation to the triangular opening abc of the basket so as to open
or close said openings. When the basket K is revolving, driven through the
pulleys E and Ĉ the pockets P and the openings'd e f acting with these pockets

page_text: in the valve plate may receive a relative motion to the basket by making the
proportions between the pulley D and the pulley F different from the proportions
between the pulley E and the pulley C. When the machine is set in rapid motion,
a stream of liquid baving suspended therein substances to be separated is caused to
fall on the drum T which covers the shafts L L, said liquid will be thrown toward
the outer circumference of the basket, and will there arrange itself in a hollow
cylinder. At the commencement of the operation, the openings in the bottom of
the basket a b c are placed directly over the openings def communicating with
pockets P. Since now the apex c of the triangular opening is situated almost
contiguous to the wall of the basket, only a very thin film of sediment consisting
of the heaviest particles will be formed against the sides of the basket and the
liquid will overflow through the openings carrying with it the lighter particles
which it is not desired to deposit. On connecting the clutch shown at Figure 16 a
very slow relative motion will be given to the valve plate and thereby to the
openings def. By doing this the sides F D of the valve, and BC of the basket
will overlap each other gradually at points approaching more and more nearly to
the centre, leaving as the actual passage for the liquid only that part of the
opening which is shaded dark in Figure 18. The effect of this is that, while the
opening is virtually receding from the outside of the basket, the heaviest particles
are gradually retained in the basket until the basket is filled. The machine is then
stopped and the material removed from the basket either in its dry state, or washed
out as previously described. It will be plain that it is not necessary to have the
two openings of triangular shape as any two openings which have two sides
inclined at a different angle to a common radius moving relatively to each other
will answer, as, for instance a radial slit in the basket and a spiral slit in the valve
plate, or two spirals with a different central progression, or two slits corresponding
to two different tangents of a spiral, or a radial slit in the valve may work together
with a slit corresponding to the chord of a circle on the inside of the basket. All
that is necessary is to form the two edges of the openings in the basket and valve
in such a manner that the remaining part of the passage shall gradually recede
toward the centre of the basket.
When it is desired to remove the starch deposited without stopping the operation
of the apparatus continuously, I employ the following apparatus, which will be
readily understood from the accompanying drawings, in which similar letters refer
to similar parts. Figure 12 represents a vertical section through the apparatus,
Figure 13 a top view or plan; Figure 14 a horizontal section through the discharge
pipes; Figure 15 a vertical section partly in perspective showing details of the
circumference or periphery of the basket, and the separating mechanism.
The apparatus consists generally in an improved centrifugal machine, which
machine may either be hung from above or supported from beneath, but in the
form shown it is supported from beneath. A represents the pedestal of the
centrifugal machine. B represents the curb surrounding the basket. C represents
the basket which is divided in sections by the annular rings c² c³. This basket is
made up as shown of a series of independent castings or rings laid one upon the
other, but may be arranged in any suitable way, but is preferably provided with
two or more annular shelves C C as shown. Projecting between the bottom and
the first shelf and between each two subsequent shelves are pipes E¹, D¹, E³, D³ as
shown.
These pipes, which are arranged to withdraw the deposited material from the
rings, are provided with lips or cutting edges extending almost to contact with the
ring periphery. The pipes E¹ E & should be adjusted so that their cutting
edges are closer to the periphery than the cutting edges of the pipes D¹ D³ &°.
These pipes as shown are supported upon an adjustable beam H, but they might
be arranged in many ways, and the position of their cutting edges with reference
to the periphery of the rings might be made adjustable by sliding or adjusting or
adjustable pieces upon the ends of the pipes instead of by moving the whole pipes
The pipe D is provided with a connection de which delivers upon the
at once.

page_text: upper surface of the next annular shelf C. The pipe D2 is provided with a similar
connection db delivering upon the upper surfaces of the shelf C. The other pipes
E, E, E all connect with a delivery pipe F'. As shown the pipes E', D¹, E, D,
E³, D are shown connected above and below by horizontal plates a. A pipe or
pipes W provided for delivering a stream or streams of water under pressure into
the space between the shelves a and the pipes E¹, D¹, E*, D2 &°. The upper
pipe D connects with the pipe E' shown in Figure 13 by which the waste products
are removed from the apparatus as will be subsequently explained. A pipe G is
provided for delivering into the mill the material which is to be separated. This
pipe is preferably located behind the discharge pipes in the direction in which
the mill is revolving, as shown in Figure 3.
The apparatus is well arranged for the separation of starch from triturated grain
carried in suspension in water; and I will describe its operation in causing such
separation. The grain itself should first be thoroughly ground, and the husk and
offal removed by a sieving or other suitable apparatus. The starch water then
containing generally the starch and gluten is led to the apparatus by the pipe G,
the object of the machine being to separate the starch from the gluten continuously.
Starch has a greater specific gravity than gluten. The starch water then is
delivered on to the bottom of the basket through the pipe G. The solid particles
in the starch water will immediately be compacted against the periphery of the
machine, lodging first in the lower corner. They will then move gradually upward,
the separation between the starch and the gluten being more thoroughly effected
as the motion continues. When the surface of the compacted mass arrives at the
point where the corner of the first tube D' meets it, it will be found that the starch
is separated from the gluten which exists as an inner ring. The tube D¹ is so
adjusted that its cutting edge will enter the compacted mass as deeply as to remove
thoroughly the gluten and a portion of the starch. The amount of starch and
gluten deposited in any given time will of course depend upon the amount fed
to the machine, and the feed therefore should be so regulated as to accomplish the
desired result.
The starch and gluten removed by the pipe D, are delivered upward through the
pipe D upon the second shelf C2 where the same operation is again repeated. A
second separation occurring there, and the gluten with a portion of the starch being
again removed upward and deposited in the same way through the pipe Db upon
the third shelf C³. Another separation precisely as before is here again occasioned,
and the last cutter D³ delivers to the pipe F¹, almost pure gluten. A certain
amount of starch may of course be removed with it, and this material being
carried to another machine the pure gluten may be removed leaving but a very
small residue of mingled starch and gluten which may be further separated if
desired. It will now be seen that after the cutters D1, D2, D3 have acted upon the
deposited starch and gluten, nothing but pure starch exists in that part of the
machine which has travelled past them. It is now desired to remove this pure
starch. In order to do this it is necessary that it be once more put in suspension
or floated in water. Water jets therefore are provided, by means of which streams
of water are caused to be jetted against the compacted starch now lying between
the sides a a, and said starch being so removed from the sides, the starch water is
carried off through the pipes E, E, E delivering into the pipe F from whence it
may be taken either to be dried as laundry starch in an ordinary separating
centrifugal machine or may be converted into glucose by well known processes.
The jets of water W should be projected against the sides with considerable force.
The water is preferably forced through a number of small perforations or nozzles
against the deposited hollow cylinder of starch. The plates a extending between
the nozzles d and e prevent the liquids which may have passed by the side of the
nozzles D from entering between the two plates so that the tubes E' E E³ receive
only such material as has passed the edges of D', D³, D³.
Now it will be readily seen that the tubes or nozzles D', D2, D³ might all be
connected with a single discharge pipe F, while the tubes E' E' E³ might deliver

page_text: material taken up by them upon the shelves next above in the same way as the
pipes D', D3, D³ do in the present apparatus. In this case the lighter material
would be removed pure while the heavier material would flow from the apparatus
together with a small amount of lighter material. I have described the apparatus
as applied to the separation of starch and gluten, but it may equally well be
applied to the separation of any other bodies of different specific gravities.
It is plain that, if desired, but one section of the apparatus need be employed or
an apparatus might be employed having but one set of removing contrivances, and
also that these removing contrivances might be arranged in various ways. It is
important that the cutting edges of the removing tubes should maintain a constant
distance with reference to the periphery of the basket, therefore the basket should
be caused to rotate constantly in the same plane, and guides may be employed to
accomplish this result or the cutting guides should be caused to move with the
basket.
What I claim and desire to secure by Letters Patent is :-
First. The process of producing pure starch which consists in causing the liquid
containing said starch to flow into a centrifugal machine and to be separated by
said machine into starch and gluten, and of then removing said gluten during the
deposit of the starch substantially as described.
Second. The process herein described of producing pure starch and removing it,
which consists in causing a suitable amount of starch water to flow into a
centrifugal inachine and to be separated thereby into starch and gluten in
continuously removing the gluten as it is deposited and in removing the starch by
the addition to it of a suitable amount of water in the centrifugal machine,
substantially as described.
Third. A centrifugal machine provided with a cutter or removing apparatus
projecting toward the periphery and adapted to be removed inward from the
periphery toward the centre, in combination with apparatus whereby such
movement may be automatically effected during the operation of the machine,
substantially as described.
Fourth. A centrifugal machine provided with a cutter or removing apparatus
projecting toward the periphery of the basket and having its cutting edge located
above the bottom of the basket and itself made automatically movable during the
operation of the machine substantially as described.
Fifth. The combination with the basket of a centrifugal machine, of a cutter
supported upon a slide or equivalent and a screw operating said slide and driven
from the power operating the basket, whereby the position of the cutting edge
may be automatically varied during the operation of the apparatus substantially as
described.
Sixth. The combination in a centrifugal machine, of a cutting edge made auto-
matically adjustable with reference to the periphery of the basket, and mechanism
whereby the speed of the movement of the cutting edge may be varied substantially
as described.
Seventh. The combination in a centrifugal machine, of a cutting edge made
automatically adjustable with reference to the periphery of the basket and a
reversing gear between the power and said cutting edge whereby the cutting edge
may be automatically advanced toward' or withdrawn from the periphery of the
basket substantially as described.
Eighth. The combination of the disc g and the friction discs e e', whereby the
motion of the disc g may be reversed, substantially as described.
Ninth. The combination of disc g, and adjustable discs e e¹, whereby the motion
of the disc g may be exactly determined substantially as described.
Tenth. A centrifugal machine provided with a delivery pipe delivering the
material to be separated upon the bottom of the basket, and a cutter or removing
apparatus extending toward the periphery of the basket, and having its cutting
edge located above the bottom of the basket for the purpose of allowing a separation

page_text: of the deposited material before the cutter or removing contrivance acts upon it
substantially as described.
Eleventh. A centrifugal machine provided with a curved tube extending from
the interior toward the periphery for the purpose of receiving and removing
deposited material and conveying it to some other location, said tube being
automatically movable during the operation of the basket substantially as
described.
Twelfth. A centrifugal machine provided with two cutting edges located in the
same horizontal plane and at different points in the circumference of the basket,
substantially as described.
+
Thirteenth. A centrifugal machine provided with two or more annular non-
communicating compartments arranged one above the other and a cutting device
adapted to remove material from one compartment and deliver the same into the
next substantially as described.
Fourteenth. A centrifugal machine provided with two or more horizontal shelves
and two cutters and removing contrivances located at different points of the
circumference above each of said shelves substantially as described.
Fifteenth. A centrifugal machine provided with two or more annular compart-
ments arranged one above the other and a cutting contrivance adapted to remove
material from one compartment and provided with an outlet into another
compartment substantially as shown and described.
Sixteenth. A centrifugal machine provided with two cutters or removing
apparatuses opening toward the circumference, and an apparatus adapted to throw
a jet of water upon the compacted material between said removing contrivances
substantially as described.
Seventeenth. A centrifugal machine provided with two cutting or removing
apparatuses projecting toward the circumference of the apparatus and located at
different points of said circumference and a guard connecting said apparatuses to
prevent the mingling of foreign substances with the deposited material which has
passed the first cutting apparatus substantially as described.
Eighteenth. A centrifugal machine provided with two cutting or removing
apparatuses projecting toward the circumference of the apparatus and located at
different points of said circumference, and two guards, one above and one below
connecting said apparatuses to prevent the mingling of foreign substances with
deposited material which has passed the first cutting apparatus substantially as
described.
Nineteenth. The combination of a centrifugal basket with a tube or opening
projecting through its periphery, said tube being made automatically movable from
the periphery inward, substantially as described.
Twentieth. The combination of the basket C, tube D, bell-crank lever B¹ and
adjusting collar E substantially as described.
Twenty first. A centrifugal machine provided with an opening through the
bottom of the basket and apparatus for causing said opening to recede from the
periphery toward the centre of the basket during the operation of the machine
substantially as described.
Twenty second. A basket for a centrifugal machine having a double bottom and
two openings, one in the upper and one in the under plate, said openings having
edges inclined relatively to each other, substantially as described.
In witness whereof I the said Sydney Pitt have hereunto set my hand
and seal this fifteenth day of February in the year of our Lord One
thousand eight hundred and eighty three.