Improvements in Machinery for Decorticating Grain.
Year: 1889

page_text: Date of Application, 6th Sept., 1889
Complete Specification Left, 5th June, 1890-Accepted, 19th July, 1890
PROVISIONAL SPECIFICATION.
Improvements in Machinery for Decorticating Grain.
We, FRANÇOIS QUENEHEN, and ACHILLE VANSTEENKISTE, both of No. 7 Allée verte,
Brussels, Belgium, Millers, do hereby declare the nature of this invention to be as
follows:-
Our invention has for its object the construction of a decorticating machine, the
mechanism of which is so constructed that the decortication is effected thereby in a
practically effectual manner, that is to say, by removing from the grain the outer
cuticle in a single piece not containing any part of the grain itself, which, freed from
its cuticle, can be readily separated into any desired fragments which preserve all the
essential constituents of the grain as this is not subject to any action that would
deprive it of those constituents, as is the case with the grinding processes ordinarily
employed. In such processes the grain, instead of being simply decorticated, is cut
and subjected to compression in such manner that the particles of bran contain
particles of the grain which afterwards lose all their essential qualities by the various
treatments to which they are subjected for removing them from the cuticle.
It is impossible to obtain the result first above described by the use of convex
surfaces operating together, so that the use of combined cylinders must be avoided for
effecting perfect decortication.
Only the combination of a convex surface with a concave surface under certain
conditions permits the desired result to be obtained, so that the construction of the
apparatus is based upon the use of a cylinder and a concentric sector these parts being
constructed and combined in a particular way.
The special conditions consist mainly in the unusual size of the cylinder and
consequently of the sector, the position of the latter relatively to the cylinder and its
special adjustment, and the form dimensions and inclinations of the grooves of the
cylinder and sector.
On the accompanying drawings Figure 1 shews a front view of the machine,
Figure 2 a side elevation, and Figures 3, 4, 5 and 6 shew details.
As shewn at Fig. 1, the machine is a twin machine, that is to say, the frame B,
of suitable strong construction, carries two cylinders C and two sectors S.
Contrary to the machines at present in use, in which grooved cylinders of very
small diameter revolving at high speed are used, the cylinders of our machine have a
comparatively large diameter such as about 134 ins. diameter and revolve at a speed
not exceeding 100 revolutions a minute, motion being imparted to them by a
pulley P fixed directly on the shaft A; the length of the cylinder is made proportional
to the other dimensions.
The combination of the cylinder with the ribbed sector is distinguished from those
of all other machines of the kind by the fact that the cylinder revolves in bearings
fixed firmly to the framing B while the sector S is arranged so as to be adjustable
relatively to the periphery of the cylinder; this combination distinguishes itself
essentially by the position which the sector occupies relatively to the cylinder, this
position being determined by the angle formed between the vertical line passing
through the centre of the cylinder and the radius passing through the centre of the
sector, this angle being always situated in one of the quadrants of the circle above
the plane passing through the horizontal diameter, and being exactly determined by
the means of the adjustment of the sector, which are of peculiar construction and
differ entirely from those actually in use for analogous purposes.
The angle formed by the central radius of the sector and the vertical central line
of the cylinder is 40° and the length, or the arc of the sector, is such that its upper

page_text: extremity is situated at an angle of 10° from the vertical centre line, while the lower
extremity is situated at an angle of 20° from the horizontal centre line of the
cylinder.
This position is very essential to the proper working of the apparatus as regards
the discharge of the decorticated grains, as these accumulate, and are compressed and
deteriorated in the grooves of the sector when the lower extremity of the latter passes
beyond or even down to the horizontal centre line, while the discharge is effected
freely, and without influence upon the material if the lower edge is situated 25° above
the horizontal.
The means for adjustment usually employed for the cylinders of grinding mills
consist in carrying the cylinder spindle in sliding bearings, adjusted by screws
operating separately in a perpendicular direction upon the spindle. This arrangement.
does not permit of an accurately parallel adjustment. of the cylinder, such parallelism
being however indispensible for obtaining products of a uniform and good quality.
In order to insure this parallelism the cylinder itself is mounted in fixed bearings
while the sector is so mounted that it can be adjusted, not in a straight line, but in a
circular arc, and can be moved through infinitely small distances to or from the
cylinder in a perfectly parallel manner throughout its entire length. For this purpose
the sector S is fixed to the ends of two arms B B' having the same configuration,
the lower ends of which are provided with eyes M accurately bored and fixed upon
a shaft A' parallel to the axis of the cylinder and capable of turning in bored
bosses bb on the casting B situated at a suitable distance below the cylinder.
Thus the sector S, arms B B and shaft A¹ being rigidly connected while the shaft is
rigidly mounted in the bosses bb, the parallel movement of the sector relatively to the
cylinder can be effected in any desired manner.
The sector is pressed towards the cylinder by two strong spiral springs R resting with
their bases on seats S' on the framing and carrying at their upper ends screwed stems s
bearing against lugs P formed on the arms B'; the springs R are enclosed in suitable
boxes B2 B2, and their elastic power is made proportional to the nature or resistance
of the material to be acted upon. At right angles to the lugs P are situated
projections on which rest the ends of a cross har T on which acts a screw spindle V
by means of which the arms are moved so as to bring the sectors nearer to or farther
from the cylinder. The screw spindle V passes for this purpose through the centre
of the cross bar and has a wheel nut V1 by means of which the cross head is pressed
downwards or is allowed to rise by the action of the springs R. The lower end of the
screw spindle is fixed in a socket on the framing.
Besides affording the above described parallelism of motion, this construction also
prevents small hard particles, such as small pebbles &c. from damaging the working
surfaces of sector and cylinder, as on the passage of such hard objects between these
surfaces, the sector will be forced away, in compressing the springs, and thus allow
the grit &c. to pass through the machine without being crushed or damaging the
surfaces.
.
Above each cylinder is arranged a feed hopper, T¹ with distributing roller, while
the material acted upon falls into a trough below containing a conveying worm for
transporting the material to wherever required. The grooves of the cylinder are
shewn in cross section to an exaggerated scale at Fig. 3. These grooves are
1 milimetre (0.04 ins.) high, and their summits are 3 milimetres (0.13 in.) apart, so
as to include 8 grooves in a distance of 26 m.m. (1 in.). The one side of the groove
rises abruptly, about at right angles, the top which is about 1 m.m. wide being slightly
rounded, and on the other side the groove has an easy inclination terminating in a
rounded bottom.
The cylinder being about 29 ins. long, the groove commences at the vertical radius
and at the one end and extends to the horizontal radius at the other end, so that it
forms a helical curve of one quarter turn upon a cylinder of 13 ins. diameter.
The angle formed by the grooves with a line parallel to the axis is therefore about 20°.
The ribs or grooves of the sector are shewn in cross section to the same scale at

page_text: Fig. 4; they do not extend continuously over the face thereof like the grooves of the.
cylinder but are arranged in sections of equal length so that the ribs of one section
alternate with the grooves of the next one, as shewn at Fig. 5.
:
In order to afford an easy construction of this surface the sector is divided into as
many sections as there are alternating parts, which are then inserted into a cast iron
bed formed in one with the arms B₁ this bed is formed with undercut sides so that
the sections when slid in from one end will be securely held therein as indicated at
Fig. 1. The separate ribbed sections are about 2ins. wide, and the distance apart of
the ribs is about 3 in. while they are about 0.08 in. (2 m.m.) high, therefore double the
depth of the cylinder grooves. The summit of the ribs is about milimetre broad
and is rounded like the cylinder ribs. The inclination of the ribs is about the same
as that of the cylinder grooves, but in the contrary direction, so that the ribs and
cylinder grooves intersect each other at an angle of about 40°. Not only is the
inclination of the direction of the ribs and grooves reversed, but also their form, that
is to say, the left hand side of the ribs is made steep and the right hand side is inclined,
so that the steep side of the cylinder grooves, in revolving is made to face the inclined
side of the segment ribs, as shewn at Fig. 6.
.It will also be seen that the steep side of the ribs does not form a continuation of
the radius of the curvature but forms an inward angle of about 15° therewith. The
sections and the cylinder are made of cast steel of very hard temper, on which even
the best files have no action.
The above mentioned diameter of 13 in. for the cylinders has been proved the
most advantageous for the work, as also the length of 29 in., so that these
dimensions, operating in combination with the special forms of grooves and ribs
above described at an average speed of 70 revolutions minimum and 100 revolutions
maximum per minute may be considered as the model proportions of the improved
decorticating machine.
It will also be seen that the grain, the cuticle of which is first split by the
summits of the ribs is afterwards rolled by the steep sides of the grooves against
the inclined sides of the ribs in passing from one section to the other until the
grain becomes entirely separated from the cuticle as above described.
Dated this 6th day of September 1889.
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Machinery for Decorticating Grain.
We, FRANCOIS QUENEHEN and ACHILLE VANSTEENKISTE both of No. 7 Allée verte,
Brussels, Belgium, Millers, do hereby declare the nature of this Invention, and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
This Invention relates to the construction of apparatus for decorticating and
disintegrating grain in which the grain is operated upon according to a method which
allows of the removal of the outer pellicle or covering at a single operation and in
a perfect manner without compressing, splitting or otherwise affecting the kernel,
which is thus obtained in its entirety or in its constitutent parts without having
experienced any loss in quantity or quality, so as to yield the maximum amount of
flour of first quality which it is possible to obtain from the grain.
This perfect result has never yet been obtained by any of the processes for the
same purpose now in use, because all the apparatus have been constructed in such a
manner that instead of decorticating the grain they split or cleave it into several
fractions, of angular shape, each of which retains part of the pellicle or equivalent
covering, which adheres firmly thereto and prevents its disagregation into grits. In
order to effect the double operation of decorticating and disagregating these fractions,
it is necessary to, submit them to repeated reducing processes, which are the more,

page_text: numerous, according as the grain is more difficult to work. It is these repeated
operations which cause the considerable losses both as to quantity and quality of
the product. The loss in quantity arises, as is well known in the production of stive
or dust, which is repeated at each operation, and which it is impossible to collect and
utilise as good flour, while the loss in quality arises from the repeated crushing and
the resulting heating depriving the flour of its savoury principles.
These imperfections in the existing processes result from the condition of the
working surfaces which all have the defect of heing provided with cannelures having
cutting edges, and all being identical in shape, that is to say that both sides of the
cannelure have the same height and are situated at the same distance from summit to
summit, so as to render the working surfaces uniformly rough, with the sole object of
better carrying along the grain, in view of a more rapid reduction, which it is
impossible to obtain with smooth surfaces, in particular when the acting surfaces
are concentric, the one convex and the other concave. Whatever may be the profile
of the grooves on these opposite surfaces, they are always in such a condition as
regards height and proximity that the grain, while being carried along, is crushed
or split even if it remains in the grooves, being cut repeatedly by the edges of
the ridges until the pieces are sufficiently small to pass between the surfaces.
Afterwards, the same operation is gone through with these particles between surfaces
in closer proximity and having smaller grooves.
Thus, with all known apparatus, forms of grooves are employed which can perform
no other work than the crushing or splitting operation described.
For effecting a perfect decortication, that is to say, the removal of the pellicle or
covering from the kernel, it is necessary so to form the acting surfaces that the grain
is not subjected to constant and useless pressures which breaks it up into fragments
without removing the pellicle, but is only subject to slight passing pressures of a
nature to loosen the pellicle on the kernel, so that it eventually splits open, and leaves
the kernel in its entirety.
This result is obtained by the apparatus which forms the subject of the present
Invention, the functions of which are based upon the combination of differential
cannelures upon the acting convex and concave surfaces.
On the accompanying drawings Figure 1. shews in cross section to an enlarged
scale the arrangement and form of the cannelures of the surfaces operating in
combination.
Figure 2 shews in longitudinal elevation the arrangement of the cannelures on the
concave surface, Figure 3 is a side view and Figure 4 a longitudinal elevation of the
entire apparatus.
In this apparatus it is the peculiar arrangement and form of the cannelures of the
concave surface, in combination with those of the cylinder which allow of the before
described temporary pressures being exercised on the grain whereby the pellicle is
separated from the kernel. The cannelures of the concave surface have a peculiar
profile, the one side rising approximately in a straight line, which unites at the bottom
with the curved sloping surface of the other side of the next cannelure while the
upper end or summit is rounded instead of being sharp.
The groove between the cannelures is of sufficient width and depth to allow the
grain to lie therein without being acted upon until it arrives at the summit of the
cannelure when it is acted upon by the convex surface of the cylinder until on
passing beyond the summit it falls into the next groove. This temporary action on
the grain is exerted by the cannelures of the cylinder which have a configuration
precisely similar to those of the concave surface, but much reduced in size, this
being necessary for preventing part of the grain from passing between the cannelures
without having been subjected to the temporary pressure.
On the other hand the grooves of the concave surface must not exceed certain
dimensions, because otherwise the grain might remain in the same groove and
never rise to the tops of the cannelures so as to be subjected to the pressing
action. The most practically useful dimensions as proved by experiments are, for the
cylinder; height 1 millimetre, distance between the summits of two cannelures

page_text: 3 m.m.; for the concave surface; height 2 m.m.; distance between the summits of
the cannelures 5 m.m. The grooves and cannelures are formed to follow a helical
line forming an angle of about 20° with the axis of the cylinder, and as the grooves
of the cylinder lie in the opposite direction to those of the concave surface the two
sets intersect each other at an angle of about 40°.
In
Practice has shewn that under these conditions no grain will escape the pressure of
the cylinder and it cannot rest intact in the grooves of the concave surface.
order to render the work more perfect, the grooves and cannelures of the concave
surface are constructed in sections the positions of the grooves of one section
alternating with those of the contiguous ones, so that each cannelure of one section
is opposite a groove of the next one as shewn at Figure 2.
This arrangement multiplies the number of pressures in this sense that a grain
arriving at the end of one section does not fall onto the following cannelure but into
that which is in line with the groove, so that the effect is repeated oftener, and is more
perfect.
It should be mentioned that the special profile of the cannelure is of great
importance for the perfect realisation of the work, because if instead of being
hollowed at one side it were straight like the hypothemuse of a right angled triangle,
the groove would not be sufficiently deep and the grain would be subject, as in the
old constructions, to a constant pressure and would be crushed and split.
On the other hand, a narrower cannelure cannot be used, that is to say, having both
sides nearly straight, because in that case it would be too weak and would break under
the action of the cylinder upon the grain, while with the form described the ridge is
wide and strong at the base and effectually resists the pressure put upon it.
The peculiar arrangement of the grooves with a view to subjecting the grain
to temporary pressures, for loosening the pellicle from the kernel being thus
determined it will be readily seen that the desired action can only take place
when the concave surface is situated over the upper part of the cylinder, so that
the grain in the grooves always falls upon the periphery of the cylinder, the smaller
grooves of which then cause the grain to pass on to the rounded summits of the
cannelures of the concave surface, while subjecting them to the desired temporary
pressure. In order to facilitate the passage of the grain between the two surfaces,
the straight sides of the cannelures of the cylinder are presented to the hollowed
sides of the ridges of the concave surface. It will be evident that if this were
arranged at the lower part of the cylinder, the grain would remain intact in the
grooves without being subjected to any action.
It would not be practicable to cover the whole of the upper surface of the cylinder
with the concave surface because the cylinder turning in one direction to the
right for example, would tend to raise from the left hand the disagregated particles,
which instead of falling would produce crushing and heating in the right hand part.
The correct position of the concave surface will therefore be on one of the upper
quadrants of the cylinder, being restricted to a length less than 45° of that surface.
By this arrangement all the grooves will deliver the grain on to the periphery
of the cylinder, and the disagregated material will pass freely away from the lower
side, the cylinder being made to turn in this direction.
Instead of being constructed of one piece, with alternating cannelures, the
concave surface is by preference constructed in sections of about 50 m.m. length,
which are inserted side by side in a cast iron segmental box S with dovetail sides, so
as to hold the sections.
As it is also very important that the surface formed by the summits of the
concave cannelures should be maintained accurately parallel or concentric to those
of the cylinder C, the latter is fixed on a strong shaft A which turns in fixed
bearings, and the adjustment of the sector S is not effected, as is usual, in guides
placed vertically to the cylinder surface by means of sliding blocks which are actuated
by independent adjusting screws, but it is effected in the direction of a circular arc,
for which purpose the frame is formed in one with two curved arms B' B₁ having at
their lower ends strong trunnions formed on the end of a strong shaft A' mounted

page_text: parallel to A in bearings formed in the framing, so that the whole constitutes a strong
rigid system.
The concave surface is supported in the position shewn by two strong spiral
springs R which rest on a bed plate S¹, and press with saddle pieces s against
lugs p on the arms B. The springs R are enclosed in suitable boxes B2 and they
can be put under more or less compression according to the nature of the grain to be
acted
upon. For this purpose the lugs p have lateral projections t on which bear the
ends of a cross beam T on which acts the screw V, so as to move the arms for the
purpose of bringing the concave surface S nearer to or farther from the cylinder.
The screw V passes through the centre of the cross beam T and has screwed upon
it above the latter the wheel nut V, which is consequently made to press the beam
downwards with more or less force. The lower end of the screw is secured in a
column situated between the two springs R.
In the present example the machine is shewn as a double or twin one, the framing
carrying two cylinders with their concave surfaces.
Above each cylinder is arranged a supply hopper T with distributing roller, while
the products resulting from the treatment pass into a shoot below common to both
cylinders, and discharging in a conveying worm of known construction.
It will be seen that by the spring adjustment of the concave surfaces, the temporary
pressure to which the grain is subjected is of an elastic nature, thereby adding to the
efficacy of the decorticating action, the concave surfaces in yielding somewhat being
subject to a slight pulsating movement as the grain passes from the grooves to the top
of the ridges, and thence into the following groove.
Having now particularly described and ascertained the nature of
our said
invention and in what manner the same is to be performed we declare that what we
claim is :-
1. In a machine for decorticating grain, the combination of a revolving convex
surface or cylinder provided with fine cannelures, or grooves and ridges with rounded
summits and arranged in a helical direction, with a concave surface the cannelures or
ridges of which have a profile consisting of a straight side with rounded summit,
and a hollowed side, so that the grains situated in the groove between two cannelures
or ridges, are only subjected to temporary pressure as they pass over the summits,
whereby a perfect decortication of the grain is effected, substantially as described with
reference to the accompanying drawings.
2. In decorticating apparatus such as is referred to in the preceding claim, the
elastic adjustment of the concave surface S for facilitating and perfecting the
temporary pressures to which the grain is subjected, by means of a pulsating move-
ment of the concave surface substantially as described.
3. In decorticating apparatus such as is referred to in the preceding claims,
mounting the concave surfaces S on two arms B' B' carried by a shaft A" parallel to
the cylinder axis so as to establish a rigid parallelism between the concave and convex
acting surfaces, substantially as described.
Dated this 5th day of June 1890.
ABEL & IMKAY,
Agents for the Applicants.