CERTAIN NEW AND USEFUL IMPROVEMENTS IN METHODS AND APPARATUS FOR REDUCING CLEANING AND DEGERMINATING WHEAT
Year: 1882

page_text: LETTERS PATENT to Sydney Pitt of Sutton in the County of Surrey for an.
invention of "CERTAIN NEW AND USEFUL IMPROVEMENTS IN METHODS AND
APPARATUS FOR REDUCING CLEANING AND DEGERMINATING WHEAT."-A com-
munication from abroad by Charles L. Gratiot of St. Louis in the County of
St. Louis and State of Missouri United States of America.
COMPLETE SPECIFICATION filed by the said Sydney Pitt at the Office of
the Commissioners of Patents on the 11th July 1882.
SYDNEY PITT of Sutton in the County of Surrey "CERTAIN NEW AND USEFUL
IMPROVEMENTS IN METHODS AND APPARATUS FOR REDUCING CLEANING AND
DEGERMINATING WHEAT." A communication from abroad by Charles L. Gratiot
of St. Louis in the County of St. Louis and State of Missouri United States of
America,
One object of this invention is to remove the germ, fuzz and other impurities of
wheat contained in the creases of the kernels as a preliminary step to the reduction
of the wheat to middlings and flour. This part of the invention accordingly consists
in a novel method and apparatus for breaking or cracking the kernels longitudinally
through their creases and then removing the germ fuzz and other impurities by
rubbing or wearing them off without crushing or grinding the germs or the half
sections of the grains.
I accomplish both this longitudinal breaking and subsequent cleaning by the
continuous operation of mechanism which completely loosens and separates the
germs and crease-dirt from their attachment to the kernels, owing to the length
of time and thoroughness with which the cracked parts are rubbed, turned and
agitated in the practice of this invention, in accordance with which they are
subjected to the influences of gravity and centrifugal force in a peculiar manner as
hereinafter fully explained. After the separation is accomplished the products of
the apparatus may be readily screened so as to leave the half kernels clean and
ready for reducing to middlings and flour.
In connection with such a mill I use other mills of similar character, but differing

page_text: in the dress of the rolls and cases in depth and number of furrows, in rate of
speed of working, and in adjustment, as set forth below, by means of which other
mills I carry the breaking, reducing or granulating operation further than in the
said primary mill, and also continue the rubbing and degerminating operation with
good results.
In the appended drawings. Figure 1 is an elevation partly in vertical section
on the line 1. 1 of Figure 2 of a complete primary breaking, cleaning and
degerminating machine.
Figure 2 is a plan or top view of the same.
Figure 3 is an elevation of a frustum shaped roll of the primary mill; and
Figure 4 is a section of the roll and case showing their furrows.
Referring to the letters upon these figures of the drawings A indicates a main
supporting frame of any suitable construction having an annular flat top B.-
O indicates a vertical burr-spindle or shaft, resting upon its lower end in a suitable
vertically sliding bearing socket D within a laterally adjustable bearing D'
mounted in an opening through a cross beam E of the main frame. The socket D is
supported upon a lever E². The spindle is provided with a belt pulley F and with
two ordinary adjustable journal bearings G G movable laterally in the bracket H
and in the top cross-beam I whereby the vertical shaft may be always positively
maintained in a perpendicular position. Fixed and truly centered upon the upper
end of the shaft is a hollow frustum-shaped metallic cracking roll K fitting within
a corresponding case L. The operating faces of the roll and case are preferably of
chilled iron or porcelain. The case is provided with a flat annular bottom or
bearing M, which rests over the flat annular top of the frame, and is made
adjustable vertically and horizontally by means of screws, so that its inner inclined
surface shall be at equal distances from the outer surface of the frustum roll at all
points. N N indicate set screws passing through the annular top of the table and
bearing against the case bottom. There should be at least three of these screws
and there may be more. 00 indicate screws passing through lugs P P which
serve to adjust the case horizontally. There should be at least three of these
screws and four may be employed. QQ indicate screws and nuts, which when the
case has been duly adjusted vertically and horizontally with respect to the roll,
serve to hold the case firmly to the table top in the adjusted position, the screw
holes through the bearing M being large enough to permit sufficient lateral
adjusting movement. The operation of these parts for the adjustment of the roll
and roll case into proper relations to each other is as follows:-The case is first
suspended, as it were upon the roll, the screws QQ being retracted and the
lever Es being operated by means of the hand-wheel or nut Q to lift the roll and
case, so that the annular bottom bearing of the case shall be clear of its bearing on
top of the fraine. As the case exactly fits the roll this will insure the adjustment
of the interior inclined surface of the case exactly parallel with the outer surface
of the roll. Then the screws N N and OO are to be merely set up snugly in
contact with the bottom of the case. The roll is then lowered by the operation of
the lever E and hand-wheel to the proper position for spacing the roll and its case,
according to the size of the kernels of grain to be cracked. This having been done
the holding screws QQ are advanced so as to firmly clamp the case down upon the
ends of the screws N, N, when the mill will be in condition for work. Any other
suitable means of adjustment may be employed. R indicates a hopper secured to
a bracket S on top of the case. This hopper delivers the grain into a saucer-like
receptacle T secured on top of the spindle and surrounded by a glass globe U
resting on the case. From this receptacle the grain falls over on the top surface
of the roll which preferably inclines outward as shown in the drawings and thence
is fed down by gravity between the roll and case. V indicates an exterior casing
which may be of wood or sheet metal surrounding the case. After the grain is
passed through the mill. it is delivered into an annular receptacle W thence out at
one side through the inclined delivery spout X. The receptacle W is secured to
the bottom of the case I so as to move with it during its adjustments and thus

page_text: always be in position to receive the products of the mill and permit their removal
by a suitable ordinary brush or scraper. The operating face of the roll is
preferably slightly bevelled or more inclined, as at X, near its top, as indicated in
Figures 1 and 3 in order that the grain may more readily find its way end foremost
between the roll and its case.
In order to effect the first object of this invention I provide furrows Y in the
frustum roll of a depth of about three-eights of an inch at the deepest part,
extending from top to bottom upon an inclination with reference to the axis of the
frustum of about thirty degrees more or less. These furrows however I prefer
not to have run around upon the same incline from the top to the bottom, but to
incline less from the perpendicular for about one-fifth of the way from the top,
and then to increase their inclination the balace of the way to the bottom
substantially as illustrated. These furrows in this, mill should be, say, about
three fourths of an inch wide at the top and about an inch and a half wide at the
bottom in a full sized roll leaving corresponding oval cleaning surfaces Z between
the shallowest parts of the furrows These cleaning surfaces or ridges Z of the
furrows being rounded slightly do not cut but simply break and then afterwards
rub or wear and clean the broken grain with only very slight, if any, flouring.
The roll of this machine I prefer to make about 14 inches in length, 7 inches in
diameter at the top, 14 inches in diameter at the bottom and provided with
about 25 furrows. These figures may be varied somewhat in the construction of
the machine but the roll must not be too long on account of danger of heating and
flouring the grain or too short on account of danger of not doing its proper work
effectively.
The case is provided with corresponding shaped furrows and ridges except that
they are reversed with respect to those of the roll. The result of this construction
is that as the grain is delivered between the roll and its case the kernels will
assume with great regularity a position to enter the furrows end foremost. In
this position, they will first by the action of the upper part of the roll, be cracked
or broken apart longitudinally through their creases the grain by preference having
been previously screened or sized, and the case having been previously trued and
set in place about the roll accordingly at a suitable distance for accomplishing this
result. The cracked and divided kernels will then pass rapidly down the furrows.
Between the point b and the bottom the half sections of the kernels will be
turned over and thoroughly rubbed on all sides and their fuzz, crease-dirt and
exposed germs are disconnected from them without breaking the germs.
Instead of having the case adjustable vertically as described
may adjust the
roll vertically within a fixed case by means of lever E at the bottom of the frame.
Instead also of having the angles of the furrows changed as described, I may have
the furrows of the same angle of inclination with respect to the roll axis from end
to end.
I am aware that it is not new to split or break kernels of wheat longitudinally
through their creases and that methods and apparatus have been devised to
degerminate and clean wheat. I am also aware that frustum shaped rollers with
diagonal furrows have been used for grinding coffee and other substances I am
also aware that horizontal disc rolls with radial furrows and rounded ridges and
that parallel cylindrical rolls with similar furrows and ridges have been employed
for cracking kernels of wheat as a step toward complete degermination and
cleaning of the half sections of the grain. But I am not aware that a degerminating
roll has been made of frustum shape with proper inclined furrows and ridges
adapted not only to crack the grain but afterwards during its gradual passage
downward under the action of gravity to turn it repeatedly in the continuous
operation of the mill and rub off and release the germs and crease-dirt from their
attachment to the kernels and finally deliver the products uncut and unground out
of the inill at the bottom of the roll. The practical results of the use of such a
frustum or nearly conical shaped degerminating roll are demonstrated by experiment
to be highly satisfactory.

page_text: This machine in addition to being used primarily to split the kernels and clean
their half parts as above set forth may by adjusting the roll and case closer
together be used to reduce grain that has been split originally by this or other
machines. But It is preferred to employ this machine for the primary work and
to use for the further reduction machines of modified construction described
below.
It will be readily understood that by this method the kernels immediately after
being broken along their creases are subjected to the influences of gravity and
centrifugal force by which treatment the too rapid discharge of the kernels is
prevented by their being over and over again thrown off from the roll by
centrifugal force and against the case with a tendency to turn over in being thrown
off and to rub against each other as well as against the roll and case and that the
half kernels in falling from the case downward against the roll are gradually fed
along or caused to approach the point of discharge in constant rubbing motion
tending to clean all their surfaces.
It will thus be seen that I have described a new method as well as an improved
apparatus for longitudinally dividing and then turning, rubbing and cleaning
kernels of wheat without grinding either the grain or its germs the operation of
which is continuous speedy economical and thorough.
Figure 5 is an elevation of a frustum shaped roll such as I employ in the second
mill to which the screened products of the first mill are delivered in any usual
way in common practice in connection with gradual reduction milling in which a
series of mills successively operate to reduce the grain and produce flour and
middlings.
Figure 6 is a section of the second roll illustrated in Figure 5 and its case
showing their furrows. This second roll and case may be and in practice in
accordance with this invention are preferably set up in a similar frame and provided
with adjusting and operating mechanism like that above described and illustrated
with respect to the primary mill and it is not necessary to again illustrate and
describe them in detail.
The products of the first mill are delivered directly to a screen or "scalping
reel" and screened and then the split grains are elevated into a bin above the
second machine to be fed through it. I do not describe in detail and illustrate
this screening and elevating mechanism because it is old and well known and I do
not confine myself to the use of any particular variety of mechanism of that kind―
I may use any well known kind merely to secure the feeding of the products of
the first mill to the second the second to the third and so on in order that I may
conveniently secure the successive operations of the mills the practical advantage
of which is due to the construction of the cones and shells and their employment
in a series as set forth, by the aid of ordinary connecting and driving mechanism.
Figure 7 is an elevation of a frustum shaped roll such as I employ in the third
mill to which the screened products of the second mill are delivered in the same
way as from the first to the second.
Figure 8 is a section of the third roll illustrated in Figure 7 and its case showing
their furrows.
All three of the rolls are of about the same length and the same top and bottom
diameters.
The second roll differs from the first (and its case correspondingly differs) in
having more furrows-say about 29-and in having its furrows more shallow say
about 5/16ths of an inch at the deepest part and also in having the furrows less
inclined from the axis of the roll say about 25 degrees more or less.
.
The third roll differs from the second (and its case correspondingly differs) in
having more furrows-say about 35-and in having its furrows more shallow say
about 1/4th of an inch at the deepest part and also in having its furrows less
inclined from the axis of the roll say about 20 degrees more or less. The second
roll should be more closely adjusted to the case than the first and the third more

page_text: closely than the second to accord with the reduction of the wheat or the diminished
size of the granulations.
The rate of speed which has been found preferable for the rolls although this is
capable of considerable variation and must be left somewhat to the observation
and judgment of experienced millers is about 300 revolutions per minute for the
first roll and about 400 per minute for the second and third rolls.
The operations of the second and third mills upon the broken or granulated parts
of the grain under centrifugal force and the force of gravity causing the utmost
change of position of the granular parts and constant rubbing action at all points
are the same in the second and third rolls as above described with respect to the
first and whatever cleaning or degerminating if any is not perfectly accomplished
by the first mill is finished by the second and third. These second and third
mills have only a breaking or cracking and then a gentle rubbing action, so that
they do but very little flouring.
The use of three mills differing in their rolls and cases, their adjustments and
speeds, as above set forth to give exceedingly good results in reducing granulating
cleaning and degerminating wheat. They show remarkably good capacity so far
as both amount and quality of work are concerned. But the new method of
milling wheat I have described and which is well carried out by employing a series
of such mills having frustum shaped spirally furrowed rolls and corresponding but
oppositely furrowed cases does not depend absolutely upon the use of three such
mills. A greater or less number in series may be used with good effect but three
is sufficient for all ordinary purposes, and generally necessary and I recommend
that number constructed and operated as above set forth. If more are employed
to further reduce the grain they should follow about the relative differences of
construction and adjustment above indicated.
But while three mills in series as above described fully indicate and operate
this invention, in practice it will be found that the product of the first mill even
after screening will largely exceed in bulk the grain originally fed to that mill.
Again on account of the closer adjustment of roll and case of the second mill its
capacity is not so great as that of the first mill. The same is true upon a com-
parison of the third mill with the second-Therefore in practice in order to work
the first mill constantly at its full capacity, it will be necessary to have two of
the second mills and three or even four of the third mills in place to work in
concert with the first mill. .
After the operation of these three mills any ordinary grinding mills preferably
roller mills in common use may be employed to finish the further reductions so
that the bran will be free from flour and middlings.
My improved method of reducing and cleaning wheat may be practised with
benefit with frustum-shaped rolls and corresponding cases with furrows of different
inclinations from those above mentioned. For instance, the furrows of the rolls
might radiate from the top of the roll to the base-that is to say-
-run fanlike in
straight instead of spiral lines while the furrows of the case might be inclined or
spiral and vice versa or the furrows of both the roll and case might even be straight
or fanlike in their spread from top to bottom of the roll and case but the construction
I have first above described is preferable.
What I claim herein as new and desire to secure by Letters Patent is
1. The herein described method of degerininating wheat by a continuous
operation consisting in first cracking the kernels longitudinally through the creases,
and then releasing the germ, fuzz, and crease-dirt from the cracked grain or half
kernels by subjecting them to the influences of gravity and centrifugal force,
whereby they are thoroughly agitated repeatedly turned and rubbed and gradually
fed along substantially in the manner set forth.
2. The frustum shaped degerminating roll having furrows provided with rounded
ridges Z and extending from top to bottom of the roll in a direction diagonal to its
axis substantially as and for the purpose set forth.
3. The combination of the case having continuous furrows extending from top

page_text: to bottom the frustum shaped roll enclosed by said case and having like but reverse
continuous furrows on its exterior surface extending from top to bottom diagonally
to its vertical axis and means by which said roll and case are suitably supported
relatively to each other whereby they are adapted to operate upon the kernels
without grinding substantially as and for the purpose set forth.
4. The combination of the frustum shaped roll having the continuous furrows
from top to bottom extending diagonally to its vertical axis arranged at a greater
angle to the axis of the roll at their lower or longer portions than at their upper or
shorter portions and provided with rounded ridges and the corresponding case or
shell having like formed continuous furrows on its inner surface arranged in a
similar manner to those on the roll but inclined in reverse direction whereby the
grains are cracked and cleaned without cutting or grinding substantially as set
forth.
5. In an apparatus for degerminating wheat by first cracking and then cleaning
the kernels in the manner described the combination of the frustum shaped roll
having the furrows continuous from top to bottom on its exterior surface and
arranged diagonally to its vertical axis the case having furrows on its inner surface
similar to those of the roll but inclined in a reverse direction and supporting and
adjusting mechanism by which the roll and case may be spaced to operate upon
different sized kernels without grinding them substantially as set forth.
6. The herein described improved method of reducing cleaning and degermi-
nating wheat by a continuous operation consisting in passing it through a series of
mills whereby it is first cracked longitudinally through the creases the germs fuzz
and crease dirt released and again successively cracked reduced and the granules
rubbed clean of flour and impurities, the granulated parts in each mill being
subjected to the influences of gravity and centrifugal force whereby they are
thoroughly agitated repeatedly turned and rubbed and gradually fed along
substantially in the manner set forth.
7. The combination of a series of mills having frustum-shaped furrowed rolls
and fitting furrowed cases as set forth constructed and arranged to successively
reduce agitate and rub first the natural kernels and then the successive granulated
products as and for the purposes specified.
In witness whereof I the said Sydney Pitt have hereunto set my hand and
seal this seventh day of July One thousand eight hundred and eighty two.
SYDNEY PITT (LB)