IMPROVEMENTS IN ROLLER MILLS FOR TREATING WHEAT AND OTHER GRAIN
Year: 1881

page_text: LETTERS PATENT to Martin Benson, of No. 52, Chancery Lane, London, for
an Invention of "IMPROVEMENTS IN ROLLER MILLS FOR TREATING WHEAT
AND OTHER GRAIN." A communication from abroad by Oscar Oexle, of
Augsburg, in the Empire of Germany, Civil Engineer,
COMPLETE SPECIFICATION filed by the said Martin Benson at the Office of
the Commissioners of Patents on the 20th June 1881.
"IMPROVEMENTS IN
MARTIN BENSON, of No. 52, Chancery Lane, London.
ROLLER MILLS FOR TREATING WHEAT AND OTHER GRAIN." A communication
from abroad by Oscar Oexle, of Augsburg, in the Empire of Germany, Civil
Engineer.
My improvements hereinafter described are supplemental to a Patent granted to
me for improvements in roller mills, dated May 29th, 1880, No. 2186. The general:
structure of my present improved roller mill is similar to the one described in my
former Patent, usually consisting of two sets of rollers properly fluted or grooved,
mounted and worked in the same frame, and provided with the additional parts
embracing my present improvements.
"
A portion of my improvement consists in the means of regulating and holding
the rollers apart and mode of working and applying the adjusting springs to the
bearings of the adjustable rollers, for adjusting the rollers together or holding their
surfaces in proper working position, and also for preventing the springs from being
unduly compressed by the regulating mechanism.
Another portion of my improvement relates to means for reversing the direction
of the rotation of one of the rollers in cach pair.
Another portion of my improvement consists in working the rollers in such a
manner by means of belting so that no undue strain is exerted on the rollers,
their journals, and bearings by the lateral strain or pull of the belts while in
motion.
Another portion of my improvement relates to the construction of the hopper :
and.the manner of feeding the grain or material from it to the rollers by a shaking. :
motion of the hopper instead of using the ordinary feeding rollers.

page_text: Fig. 1, Sheet 1, is a sido elevation of a roller mill partly in vertical section for
more particularly showing the improvement relating to the hopper and mode of
imparting the shaking motion thereto.
Fig. 2 is a transverse vertical section of the mill.
Fig. 3 is a top view of the machine partly in section for showing the arrange-
ment and action of the springs for acting on the adjustable roller bearings, and
Fig. 4 is an enlarged horizontal sectional view of the corner of the machine
through the adjustable springs and mechanism.
Fig. 5, Sheet 2, is a side elevation of the machine.
Fig. 6 is a transverse sectional elevation, and
Fig. 7 is a top view of the same. The Figs. of Sheet 2 are for showing the
application of the improvement for driving the rollers by belting to prevent any
undue strain on the rollers, their journals, and bearings.
Fig. 8, Sheet 3, is a separate enlarged side elevation of the hopper and mechanism
for working it.
Fig. 9 is a longitudinal sectional view of the same including a transverse section
of the rollers, and
Fig. 10 is a partial transverse section of the hopper showing the parts for
working it.
In one arrangement of the two pair of rollers A, B, and A¹, B¹, Fig. 3, the outer
roller of each pair revolvo slowly and the inner ones rapidly, and the rollers of
each pair revolve in the same direction.
Working the rollers in this manner is described in my Patent of May 29th,
1880, No. 2186, but inasmuch as the machinery is more or less connected with the
working of some of my present improvements, I will thereforo again describe the
means of working the rollers to make my present improvement more clear.
Upon the shaft e, Fig. 3, of the inner roll A of one pair, a pulley f is secured
from which a band leads to the driving power. A gear wheel g on the shaft of
this roll engages with a similar gear on the inner roll A¹ of the other pair, so
that these rolls are thus revolved in opposite directions at the same speed. The
shaft e first stated also carries a pinion & which engages with a similar pinion i
upon a shaft crossing the frame at a point between the inner rolls, and carrying a
bevel pinion at the opposite side of the frame, and which matches with a bevel
gear Zon the shaft carried in bearings at side of the frame. This sido shaft
provided at each end with a worm m, Fig. 1 and 3, one being right and the other
left hand, and each engaging with a worm wheel n on the shaft of the outer roll B
of each pair, so that these rolls are thus revolved in the same direction as the
inner rolls and at slow speed. This gives a very compact and effective arrange-
ment for operating the two pairs of rolls, as described, from a single driving pulley,
and in which the cross and side shaft connections equally distribute the strain upon
the machine.
is
It is obvious however that only one pair of rolls may be used to carry out my
Invention. As the sharp ridges of the rolls must not be pressed one into the other,
the arrangement for setting the adjusting roll must be such as to allow it to yield
against the pressure of double springs, but prevent it from pressing against the
ridges of the non-adjusting roll. In Figs. 3 and 4 I have shown the means by
which this is effected more clearly, and will now specifically describe them.
The fixed blocks or bearings C, C, of the inner roll A are preferably set between
walls in pepressed parts of the top plates of the side frames, while the sliding
blocks or bearings D, D, of the adjustable roll B are sented in said depressed parts,
and both are secured upon their seats by a top binder E provided with oil cups for
the roll journals. The adjustable roll has a yielding pressure given to it by coiled
springs t arranged within tubular parts 8 extending inward from the front corners
of the side frames on a line with the sliding blocks against which they press, and
the means for regulating such pressure consists of a screw u provided with a
follower v at its inner end bearing against the outer end of said springs, and a
surrounding screw sleeve w provided with a hand wheel F on its outer end, the

page_text: screw of the surrounding sleeve fitting the external screw of the inner sleeve. The
outer screw sleeve t is secured to the outer end of the tubular frame parts by the
collar y, so as to be free to be turned by the hand wheel F which is at the front of
the frame; but being prevented from endwise movement when so turned to the
right it will screw the inner sleeve inward, and by its follower compress the
springs and increase their pressing force upon tho roll. The reverse movement of
said hand wheels will diminish the pressure of said roll.
In order to prevent the spiral springs from being unduly compressed by the
adjusting screw sleeve u a stop pin n¹ is screwed through the tubular frame a or
otherwise attached thereto, and inado to project inside the tubular frame sufficient
to allow the follower for compressing the springs & come against the stop pin n¹,
and thereby prevent any further compression of the springs by the adjusting screws,
the stop pin n' being set so that the springs t can never be acted on or compressed
by the regulating screws and sleeves beyond the maximum resistance for which the
springs are intended.
I prefer to use double springs one within the other, and of right and left pitch,
to obtain an uniform pressure. To prevent the contact of the roll ridges under
such pressure, and which would cause them to become locked together, stop studs o
are arranged between the bearings C and D, and are supported thereby, said studs.
being provided with screw nuts p, which are set so as to receive and support the
sliding bearings, so that the roll ridges cannot meet. This is independent of the
means by which the distance between the rolls is adjustable, and therefore such
adjusting means can never cause the rolls to come in contact. These stop studs
can have no fixed connection with either bearing block, and in fact the sliding
blocks can move freely over them. When the roll B is properly set the nuts p are
secured by jam nuts.
The distance which tho adjustable roll can yield from the non adjustable roll is
determined by stops formed by the inner ends of the tubular parts s, and against
which the sliding blocks will act to prevent the separation of the rolls beyond a
proper limit, so that whether the roll B be adjusted toward or from the roll Å such
adjustment is limited between the stops o on one side on the sliding blocks and by
the tubular parts s on the other side. It is however important in reducing
different kinds of grain to set the rolls at different distances apart, and for this
purpose I provide screw steins x locked by T-heads to extensions r from the sliding
bearings, and passing centrally through the springs t, and their pressure regulating
sleeves are fitted on their outer ends with hand nuts G just outside the hand
wheels F, there being jam nuts on the ends of said screw stems to lock these
outer hand nuts thereon. The hub of the outer hand nut has a screw fitting the
screw stem x, and it also bears against the outer end of the outer sleeve w, and
this bearing is necessary to render the follower sleeve independent of the outer
hand nut, so that these hand wheels and nuts bear one upon the other in the line
of their axis, and maintain such relation both in the adjustment of the springs and
of the roll by the action of the springs. These screw stems do not turn in their
connections with the sliding blocks, but the outer hand nuts are turned upon them,
and if so turned to the right the screw stems and their connected bearing blocks
will be drawn outward against the pressure of the springs. The turning of these
land nuts to the left will allow the bearing blocks to be forced inward by the
springs, and the distance between the rolls is in this way regulated to suit the
work, and when so regulated the jam nuts serve to make the set secure. This
adjustment of the roll, while being independent of that of the springs, yet the
devices for effecting both are combined in a single device, and independent of the
means by which the minimum distance between the rolls is effected.
The arrangement for operating the sleeve followers u and for forming bearings
for the outer hand-nuts independent of said sleeve-followers are the means by which
I obtain the combined device for each sliding block.
The tubular parts 8, 8, of the frame serve to enclose the springs,

page_text: It is important to notice that the means for operating the rolls not only equalize
the strain upon both sides of the frame, but the worm gear connections allow the
outer roll to slide toward and from the inner roll without effecting such con-
nections, and besides the worm gear gives a much slower motion of the outer roll
than could be obtained by spur gear, which is very important.
By experience I have ascertained that the rollers working in opposite directions
is better for the first two or three reductions of the wheat, and from the fourth to
the last operation in reducing the grain and its parts it is better to work the
rollers in the same direction, as described in my Patent of May 29th, 1880,
No. 2186, and at an increased speed of 600 to 700 revolutions per minute; by
thus changing the direction of the motion of the rollers in the same machine and
increasing their speed I am enabled to perform all the operations on the grain and
its parts by one machine or pair of rollers and grooves of the same size instead of
using several pairs of rollers with finer or courser grooves for treating the grain
and its parts in the process of reducing it to flour. The means for reversing the
motion of one of the rolls in each pair are represented on Sheets 1 and 2 in
Figs. 3 and 7. The manner of working the rolls A, B, and A', B¹, Fig. 3, in the
samo direction in each pair by means of gear wheels and worm screws m has been
described.
For working the rollers in each pair in opposite directions the same gear
wheels and , Fig. 3, are used on the inside roller shafts A, A', but instead of
using the worm screws m, m, and worm wheels n, n, for working the outsido
rollers B, B¹, the worm wheels n, n, are removed, and instead thereof gear wheels W,
Fig. 7, are placed on the ends of the outer roller shaft, large enough to work into
the pinion wheels o¹, o', on the inside roller shafts A, A', which causes the rollers
to revolve in opposite directions or turn towards each other by motion applied to
the driving pulley f. As before stated the rollers move in opposite directions for
the first two or three operations on the wheat, and from the fourth to the last
reduction of the grain and its parts into flour they are made to move in the same
direction as before described and at the required increased speed. The two rollers
in each pair may be worked at a uniform or differential speed, this may be
effected by proportioning the gear wheels for giving them the required motion.
The pair of rollers on one side of the same machine may be worked or moved in
the same direction, while the pair on the opposite side of the machine may be
made to move in the opposito direction. One pair of the rollers could then be
used for the first two or three operations on the grain, and the other for completing
the operation and for regrinding bran and cleaning the grinding offals. In such a
machine the top and bottom hoppers would have to be divided, so as to keep the
products of each pair of rollers separate, and a division would have to be made in
other machines for acting on the material coming from each pair of rollers. A
separate machine would have to be employed for the purpose.
The next portion of my improvement relates to driving the rollers by means of a
belt in such a manner as to prevent the lateral strain or pull of the belt from
injuriously acting on the rollers or roller journals and their bearings. The means
for doing this is shown on Sheet 2, and consists in using a driving pulley C 4
attached to the intermediate shaft with internal gearing, as more fully repre-
sented in Fig. 6, for working into the pinion D on the roller shafts A for imparting
motion to the two pairs of rollers A¹, B³, and A, B, either by gearing V, V, on the
ends of the roller shaft or by worm screws m and worm wheels n, in the manner
before described and represented in the several Drawings. It will be observed 5
that the driving pulley for working the rolls is attached to the intermediate
shaft j, consequently all the lateral strain or pull of the belt is received by the
intermediate shaft, and thereby prevents it acting on the rollers or roller journals
and bearings.
The next portion of my improvement consists in feeding the grain, neal, or 5
material being treated from the hopper to the crushing rollers by a shaking

page_text: motion imparted to the hopper instead of feed rollers as are ordinarily used. For
this purpose the bottom of the hopper is separately constructed from its sides or
body, and suspended to the sides of the hopper body by springs in any suitable
manner to allow a free shaking motion. The bottom of the hopper is attached to
the body of it by means of bits of cloth, canvas, or leather, to prevent the material
coming out of the hopper excepting at the regulating feed gate. The shaking of
the hopper is effected by motion usually taken from one of the roller shafts placed
in any suitable position for working it through the medium of levers or other
suitable mechanism; means are also used for throwing the feed motion in and out
of gear when required.
This part of my improvement is represented on Sheet 1, Figs. 1 and 2, where
the hopper is shown attached to the machine; and Sheet 3, Figs. 8, 9, and 10
showing the hopper drawn to an enlarged scale. The hopper a, a, is made double,
and is attached to the standards d, d, secured to the top of the machine, as repre-
sented; the bottoms b, b, are suspended to the outer sides of the hopper by
springs c, c, and by strips of canvas, cloth, or leather 8, 8, attached to the inner
sides and ends of the bottom and sides of the hopper, as fully shown in Figs. 9
and 10; by thus attaching the bottoms of the bopper it is left free to move.
hopper is divided into two parts by a ridge picco, as represented in Fig. 9, cach
side of it is provided with a regulating feed gate for feeding tho grain or
material being treated into the supplemental hoppers t, t, over the rollers, as
shown.
The
The bottoms b, b, of the hopper receive their shaking motion from a revolving
cam or eccentric g attached to the roller shaft A through the medium of the lever e
secured to the vibrating shaft working in the standards d, and the forked
levers i, i, attached to each of the hopper bottoms b, b, by the cross bars m, as
shown. The lower end of the lever e is supplied with a friction roller f for
working on the eccentric, the friction roller is kept in constant contact with the
eccentric g by the spiral spring o, one end of which is attached to the body of the
machine, and the other to the lover e. If desired the cam or eccentric g may be
made for giving one, two, or more vibrations to the shaking levers by one
revolution of the roller A. By thus using a shaking motion for acting on tho
hopper bottoms b, b, for feeding purposes, grain and similar material of any kind
and condition can be fed to the crushing rollers more regular and uniformly.
Having described the nature of my improvement, and mode of constructing
and working the same, what I claim as new is,―
1. The manner herein described and represented for adjusting the distance
between the rollers A, B, and A', B¹, and for regulating the pressure of the adjustablo
rolls in combination with the guard or stop pin n' for preventing an undue
pressure on the spiral springs t, for the purposes hereinbefore described.
2. The means employed for reversing the direction of the motion of one of the
rolls in each pair, and applied to one or both pairs of rolls in a double roller mill,
in the manner and for the purposes bereinbefore described and represented.
3. The pulley C provided with internal gearing and mounted on an intermediate
shaft or stud j, and made to work the pinion D on the roller shaft A for working
the roller through the medium of gear wheels or screw worins and gearing com-
bined for preventing the lateral strain or pull of the driving belt on the pulley C
from acting injuriously on the rollers, their journals, and bearings, as herein before
stated.
4. The double hopper a, a, constructed as represented in its parts with loose or
vibrating bottoms b, b, and provided with means for shaking and regulating the
quantity of feed from the hopper to the rollers, in the manner and for the purposes
hereinbefore described.
5. The combination of the hopper a with a roller mill and eccentric g, lever e,
and i, i, and spiral spring o for shaking the hopper bottoms b, b, as described and
represented,

page_text: 6. The lever n for stopping or starting the feed or shaking motion by placing
the end of the lever e on or off of the eccentric g, in the manner represented and
before described.
In witness whereof, I, the said Martin Benson, have hereunto set my
hand and seal, this Eighteenth day of June, in the year of our Lord
1881.
MARTIN BENSON. (LS.)