IMPROVEMENTS IN ROLLER MILLS FOR CRUSHING AND GRINDING GRAIN AND OTHER LIKE MATERIALS
Year: 1877

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN ROLLER MILLS FOR CRUSHING AND GRINDING GRAIN AND
OTHER LIKE MATERIALS." A communication from abroad by Lorenz Nemelka,
of Simmering, near Vienna, Austria.
Sealed the 4th January 1878, and dated the 31st August 1877.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at
the Office of the Commissioners of Patents on the 31st August 1877.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN ROLLER MILLS
CRUSHING AND GRINDING GRAIN AND OTHER LIKE MATERIALS." [A communication
frota abroad by Lorenz Nemelka, of Simmering, near Vienna, Austria.]
FOR
This Invention relates to improvements in roller mills chiefly designed for
crushing and grinding grain, and particularly to means for varying the relative
heights of the axes of the rollers, and also their relative horizontal distances for
the purpose of producing a greater or lesser pressure of the one roller on the other.
By arrangements for displacing levers, screws, wedges, or excentrics connected
directly or indirectly with the roller bearings, the variations of vertical and
horizontal distances and the required pressure between the rollers are obtained.
The said levers, screws, wedges, or excentrics may be provided with dials and
pointers for indicating either in units of weight the amount of pressure, or in
units of distance the space through which the roller has been displaced.
In a roller mill constructed according to these improvements the grain, pre-
ferably already crushed, passes from a hopper over delivery rollers between pairs
of grinding rollers, out of which the ground product falls into another hopper,
whence it may be taken for further treatment. The said delivery rollers may
be provided with arrangements for increasing or decreasing the amount of grain
allowed to pass to the grinding rollers.

page_text: In each pair of grinding rollers the bearings of the one roller are adjustable
while the bearings of the other roller are fixed. The bearings of the adjustable
roller may be arranged at the ends of a pair of levers, the other ends of which
are pivoted to an axle; on this axle an excentric may be placed. When this
excentric is turned by means of a hand lever fixed to the said axle the adjustable
roller will be moved towards or away from the other roller, as required by different
qualities of grain.
2
In order to prevent tho jamming of the adjustable roller a set screw may bo
arranged under each of the bearings of the said adjustable roller. This pair
of set screws may be adjusted either separately or together; in the latter case
a worm wheel and worm screw with a hand wheel may be used.
The hand lever for moving the excentric may be fixed in any desired position
by a spring, or by a screw fixed in any one of a series of notches in a segment.
The blocks, in which the axle with the excentric is pivoted, are screwed to
the standards, and may be adjusted on the same, if the bearings of the roller
become worn, to ensure the parallel position of the rollers to each other.
The pressure of one roller on the other depends upon the variations of the
relative height of their axes. This height may be altered according to the pressure
required by displacing the block carrying the axle with the excentric, and by
adjusting the set screws arranged beneath the bearings of the adjustable roller.
In the above-described arrangement the grain passes through a pair of rollers,
one of which rollers has fixed bearings, whilst the other has adjustable bearings.
Instead of this arrangement a set of three rollers, one with fixed bearings and
the other two rollers with adjustable bearings, may be employed, so that the
grain, after passing firstly through the roller with the fixed bearings and the
upper roller with adjustable bearings, will be reground by passing through the
same roller with fixed bearings and the lower roller with adjustable bearings.
A self-acting pressure and adjusting arrangement may be obtained by the use
of bent levers, whose shorter arms press against the adjustable bearings of the
roller, whilst the ends of their longer arms are subject to the pressure of weighted
levers.
The arrangements of this apparatus may be such that the rollers, when adjusted,
are kept from approaching closer to each other, but not from receding further
from each other, in case an unusually hard or resisting substance should come
between the rollers.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 28th
February 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, London. IMPROVEMENTS IN ROLLER MILLS FOR
CRUSHING AND GRINDING GRAIN AND OTHER LIKE MATERIALS." A communication
from abroad by Lorenz Nemelka, of Simmering, near Vienna, Austria.
This Invention relates to improvements in roller mills for crushing and
grinding grain, and particularly to means for varying the relative heights of the
axes of the rollers to each other, and also their relative horizontal distances, for
the purpose of producing a greater or lesser pressure of the one roller on the other.
By arrangements for displacing certain levers, screws, wedges, or excentrics
connected directly or indirectly with the roller bearings, the variations of vertical
and horizontal distances, and the required pressure between the rollers are obtained.
The said levers, screws, wedges, or excentrics may be provided with dials and
pointers for indicating either in units of weight the amount of pressure, or in
units of distance the space through which the respective roller has been displaced.
In a roller mill constructed according to these improvements the grain, prefer-
ably already crushed, passes from a hopper over delivery rollers to between pairs
of grinding rollers, out of which the ground product falls into another hopper,
from whence it may be taken for further treatment. The said delivery rollers
may be provided with arrangements for increasing or decreasing the amount of
grain to be allowed to pass to the grinding rollers.
In each pair of grinding rollers the bearings of the one roller are adjustable
while the bearings of the other roller are fixed. The bearings of the adjustable
roller may be arranged at the ends of a pair of levers, the other ends of which are
pivoted to an axle; on this axle excentrics may be fixed. When these excentrics
are turned by means of a hand lever fixed to the said axle the adjustable roller
will be moved towards or away from the other roller, as required for different
qualities of product.
In order to prevent the adjustable roller from being jammed together with the
other a set screw may be arranged under each of the bearings of the said adjust-
able roller. This pair of set screws may be adjusted either separately or together;
in the latter case à worm wheel and worm screw with a hand wheel may be used.
The hand lever for moving the excentric may be fixed in any desired position by
a pawl falling into, or by a screw to be fixed into any one of a series of notches in
a segment.
The blocks, in which the axle with the excentrics is pivotted, are screwed to
the standards, and can be adjusted on the same, in case of the bearings of the
roller being worn, so as to ensure the parallel position of the rollers to each other.
The pressure of the one roller on the other depends upon the variations of the
relative height of their axes to cach other. This height may be altered according
to the pressure required by displacing the block carrying the axle with the
excentric, and by adjusting the set screws arranged beneath the bearings of the
adjustable roller.
In the above-mentioned arrangement the grain passes through a pair of rollers,
one of which rollers has fixed bearing, whilst the other has adjustable bearings.
Instead of this arrangement a set of three rollers, one roller with fixed and the
other two rollers with adjustable bearings, may be employed, so that this grain,
after passing firstly through the roller with the fixed bearings and the upper roller
with adjustable bearings, will then be reground by passing through the said roller
with fixed bearings and the lower roller with adjustable bearings.
A self-acting pressure and adjusting arrangement may be obtained by the usa
of bent levers, the shorter arms of which press against the adjustable bearings of

page_text: the roller, whilst the ends of the longer arms are subject to the pressure of
arrangements of weighted levers.
The arrangements may be such that the rollers, when adjusted, will be
prevented from approaching closer to each other, but not from receding further
from each other, in case an unusually resisting substance should come between the
said rollers.
And in order that the said invention may be more fully understood I will now
proceed more particularly to describe the same, and for that purpose will refer to
the accompanying Drawings.
With reference to Sheet 3, Figure XI. and XII., and Sheet 4, Figures XIII.,
XIV., XV., a is the hopper from which the grain, by preference in the form of
semolina or middlings, falls through the delivery rollers b, b, down to the grind-
ing rolls c, d, and from there arrives crushed or as flour at the spout f, from
whence it can be taken for the further operations.
By means of the adjustable slides e, e, on the delivery rollers b, b, a greater or
lesser quantity of grain can be allowed to pass out of the hopper.
The bearings g of the fixed rolls d, d, are either cast with the frames or bolted
on to the same.
The bearings of the outer rolls c, c, are cast on the arms of levers pivoted on
the shafts by means of the excentrics /, which form a part of or are fixed on the
said shafts. These excentrics are arranged for the purpose of adjusting (by
means of the lever m keyed fast to the shaft k) the rolls c in the necessary distance
apart, as required for working up the grain under operation.
To prevent the rolls c from becoming jammed to the rolls d, there are set
screws n arranged on the framing under the bearings of the rolls c, and the
bearings are set on to these screws. These set screws n may be worked, either
singly or in pairs, by a worm with wheel o and spindle 7, on which the hand
wheel is fastened, as shewn in Figure XV.
The lever m can be adapted to any position required by means of a pawl falling
into the toothed segments, Figure XV. This toothed segments is fixed on to
the framing, and may conveniently be replaced by a segment with slit, in which
the lever can be held fast in any position required by means of a screw fixed to
the said lever.
The brackets in which the shafts & have their bearings are fixed on a bed plate
or table h, and are arranged so as to be set further inwards when they may have
become worn, in order that the rolls may always bo kept perfectly parellel, as
shown in Figure XI.
The greater or lesser pressure or crush of the rolls is dependent on the height in
which the axis of one roll is varied from that of the other; and this height can
be regulated according to the pressure required by shifting the brackets and
setting the screws n; and in order further to prevent any giving way of the
brackets when at work, they are secured by the bolts described above, and by set
screws, as shewn in Figure XI.
As shown in Figure XIX., Sheet 7, the mill may be provided with a third pair
of rolls, arranged on the same principle and having the bearings of the one roll
fixed, and those of the other adjustable by excentrics, as above described. This
arrangement is devised for the purpose of enabling the grain to pass from the
hopper two distinct times between pairs of rolls, and to be thereby completely
ground.
The mill can be built either single or double, that is to say, with either 3 or 6
rolls, and in the latter case it will be provided with two sets of 3 rolls each, the
rolls of each set being arranged at an angle, as described above, and each set
working separately from the other.
The mill, shewn in Figure XIX. of the accompanying drawings, is provided
with a double set of rolls, and the description of the one set of rolls is applicable
to the other. This mill is more especially constructed for grinding purified
middlings into fine flour.
The middlings pass from the hopper a through the delivery roller b, the

page_text: quantity passing being regulated by the slide c to the grinding rolls d, e, and
from these to the grinding rolls e, f, thereby becoming twice ground at one feed
or filling, thence dropping out through the spout g. The roll e rests in fixed
bearings h, and cannot be adjusted during work, but the two rolls d, f, have
their respective bearings i, i, cast on to the arms of levers m, which are pivoted
on the shafts k, k, by means of excentrics 1, 1, which are welded on the shafts k, k,
Figure XIX. These excentrics 1, 1, are designed for the purpose of enabling
the rolls d, f, to be adjusted to any required distance from the not adjust-
able roll e by means of the levers m, m, keyed onto the shafts k k.
In order to prevent the rolls d, f, from getting jammed to the roll e, the move-
able bearings, i, are arranged adjustable on set screws n, n, Figure XIX.
The centre lines of the rolls d, f, lie a little above an imaginary line o, k,
drawn from the centre line of the roll to the centre line of the shafts k, and
the nearer this axis or centre line of the rolls d, f, is adjusted towards this line,
the greater will be the pressure between the rolls d, e, and f, e, and a self-acting
pressure is always exerted, that is to say, the rolls d and f will give way upwards
whenever the pressure becomes too great, or a hard substance gets between
them. Hence the pressure between the rolls d, e and f, e, can be modified, as
required, by adjusting the set screws n, n, on which the bearings i, i, sit.
The levers m, m, can be adapted to any position required by means of set
screws 1, 2, which work in slits cast in the brackets q, q, Figure XIX.
The shafts rotate in bearings on the brackets q, r, Figure XIX. These
brackets are bolted on the framings and can be slid out singly whenever the
bearings are worn, so as to enable the rolls d, f, to be continually kept up in
a perfectly parallel working position.
All the bearings are arranged for automatic oiling, and their oil boxes will
be described later in this Specification.
Each roll is provided with a scraper or knife pressed against it, automatically
for scraping off any grain or flour sticking to the roll.
The rolls are driven by three pinions on the roll shafts connected to the driv-
ing pulley, and these pinions are not all of the same size, whereby the rolls
obtain the required difference of speed of rotation, and in certain processes of
grinding these pinions may be dispensed with, and the rolls allowed to rotate
by mutual friction.
The two brackets s are fixed on the same bed or table b¹.
The rolls are made by preference of chilled cast iron, but glass or other
hard material can be used instead.
The self-acting pressure and fixing arrangement of the rolls can be also con-
structed in the following manner, as shown on Sheet 5, Figures I., II., XVI.;
Sheet 6, Figures III., IV.; and Sheet 7, Figures XVII., XVIII.;-With refer-
ence to Figures I. and II., on Sheet 5, of the Drawings, the four levers f, f,
pivoted to the pins g press at h on the adjustable bearings of the outside rolls
and are arranged with a leverage of one to six. The horizontal angle levers i
work against the levers f, f, and as the levers i, i, have a leverage of one to fivo
and a quarter, the pressure that can be brought to bear on the rolls is equiva-
lent to a leverage power of one to thirty one and a half, as shown in Figures II.,
XVI., XVIII.
The following arrangement is adapted for the purpose of employing only two
weights for these four levers :-A step or bearing is arranged on one side
of the mill, the two ends of which step rest each on one end of a lever i, that is
to say, the end u presses on the lever which has its fulcrum at e, and the end w
on the lever with fulcrum at .r, as shown in Figures I., II., and XVI., and the
lever on which a sliding weight m is adapted, presses on the centre of this
The leverage of 7 can be varied according to the position given to the weight m,
and can be changed still more by displacing the pin n; the proportions of varia-
tion of this further arrangement are one to two and one to six, and hence the
sum total of the leverage that can be brought to bear on the rolls is from one
to sixty-three up to one to one hundred and eighty-nine, as shown in Figure II.
bearing k.

page_text: By this arrangement, so high a pressure can be obtained that rolls up to 30
inches in length can be employed without going below the minimum pressure
required for the heaviest operations of grinding.
By employing such an extent of leverage, a small weight can be used on
the lever, thereby facilitating the handling of the lever when the rolls require
to be drawn back.
The lever is provided with a graduated scale for shewing the total pressure
on the rolls, according to the position of the weight and that of the pin n,
see Figure II.
The outside rolls, Figure II., can be firmly adjusted in the following manner: -
The levers have each an arm a cast on them, which rests against the excen-
tric c¹ fixed on the shaft b¹, thereby enabling the whole of the pressure to be
thrown on these excentrics, Figure II., XVII. By rotating the shaft b, the
outside rolls will likewise be set in motion and fixed in any distance apart
from the inner rolls that may be required for the work to be done. The shaft 6¹
rotates in bearings bolted on to the brackets. On the shaft 1 a hand lever e¹ is
keyed to serve for rotating the shaft, Figure I., II. The shaft b¹
can be set fast by means of the bolts f¹, having their heads working in slits
cast in the bearings d¹.
In order to enable each end of the outside bearing to be regulated indepen-
dently, for the purpose of obtaining a perfect parallelism of the outside rolls
to the inner rolls, there are screw bolts g' arranged in the arms a', and these
bolts g press on to the heads h¹, likewise arranged in the arms a', which heads
are in direct contact with the excentrics, as shown in Figures I., II., XVII.
The bolts g can also be employed for regulating when the mill is at work,
in case either bearing becomes more worn than the other.
A further plan for firmly adjusting the outer rolls is shown on Sheet 6,
Figures III, IV. Here the wedges o are arranged between the bearings of the
rolls, and by screwing up the nuts, the distance between the rolls can be
increased or lessened, as required. An index finger fastened to the screw end
of the wedge and moving against a properly graduated scale, will show the
distance between the rolls.
In working, it sometimes happens that middlings or sharps of different sizes
have to be ground between the rolls, and this renders it of importance to be
able to regulate accurately the distance between the rolls, and besides this, the
wedges are of service when brittle rolls, for instance, of glass or porcelain, are
employed, as they will take off a portion of the pressure in cases when undue
pressure is put on, and will thereby save damage to the rolls.
When coarse middlings or sharps are being worked up, the rolls do not touch
each other, and then the whole pressure is taken up by the wedges o. This arrange-
ment of the wedges likewise permits the full leverage and a high pressure to be
put on the rolls without any giving way of the rolls when the proper quantity
of material runs through them as absolutely necessary to ensure grinding.
On stopping work, the pressure must be taken off and the rolls drawn back;
and this drawing back is facilitated by the levers f, having below an arm by.
which they can easily be freed, and then the rolls can be drawn back by means
of the screws at h, as shown in Figure II.
Under the arrangement of the double set of levers (levers 7) the drawing back
of the rolls quickly is. much easier, since only two levers have to be handled
which can be lifted without great exertion, and made fast by pins to be set into
holes conveniently adapted in the brackets, as shown in Figures I. and II.
In order to keep the levers in a perfectly horizontal position when the bear-
ings have become a little worn, the small pieces of thin sheet metal or other
can be driven in at k, between the lever and the bearing.
The screw bolts gl, Figure II., are likewise intended for setting the adjustable
rolls perfectly parallel to the fixed ones, and this is accomplished as follows:-
A piece of paper or sheet metal is placed between the adjustable and the fixed

page_text: rolls and the screws g set right and left in such a manner that the sheet becomes
evenly situated between the rolls, and then the set nuts of the bolts g' are
screwed up tight enough to hold the arm a fast, as shown in Figure II.
It will be found that by arranging the rolls perfectly parallel to one another,
a great saving in power will be effected and the wear of the rolls lessened.
In cases when a quick and sure parallel setting of the rolls is required,
irrespective of outlay, the arrangement shown in Sheet 6, Figure III., should
be selected. Here a worm wheel replaces the nut on each bolt, each pair of
wheels being moved by a worm arranged on a suitable spindle, and each worm
can be operated independently of the other, thereby allowing the corresponding
rolls to be at all times arranged perfectly parallel. It will be seen by Figure III.
that the slightest motion of the hand wheel will impart a corresponding motion
to the wedges, and from these to the bearings and the rolls.
All the bearings of the rolls are self-oiling, and the arrangement for this
purpose will be described below.
Each roll is provided with a scraper or knife d', Figure XI., Sheet 3, pressing
automatically against the roll, in order to remove any material sticking to the
roll.
The rolls are driven by the pulley e¹ and the pinions f* and g*, and for certain
descriptions of work it will be found necessary to have, as shown in Figure XIII.,
besides the pinions f* and *, a cog wheel to each roll, these cog wheels having
all the same or different speeds.
The brackets or standards are bolted on a bed plate h¹, as shown in Figure XI.,
XII.
The arrangement shown in Figure II. is peculiarly adapted for working up
hard grain, and furthermore, the self-acting mechanism for regulating the
pressure can be constructed as follows, see Sheet 1, Figures V. and VI., and
Sheet 2, Figures VII., VIII., IX., and X. The middlings or sharps are thrown
into the hopper a and run over the delivery rolls b, between the grinding rolls c, c,
to the spout or chute d, Figures V., VI.; they then come into an elevator and
are taken on for further operations.
The rolls are regulated as follows:-The two middle rolls have fixed bearings
and remain fast; the two side rolls sit on the levers e, e, see Figure VI. and IX.
These levers have sockets f cast on them to receive the set screws
The screws g press on the iron plates h, also set in the sockets f, and the plates h
press against india-rubber buffers i which again press against iron plates j.
The brackets have each two bearings cast on them, in which the shafts m
rotate, and on the shafts m the excentrics n are fixed each in the same direction.
As shown in Figures V. and VI., on each excentric shaft m a toothed wheel o
is keyed, in which a pinion p locks. This pinion sits on a pin or short shaft
provided with a crank, and the pin works in a bearing cast on the bracket .
By means of the crank the pinion p can be rotated to the right or left, and
the excentric pressed towards or from the buffer i and the lever e, so as to
exert or take off the pressure of the lever on the rolls, as may be required.
When the rolls get apart, the head of the excentric will press against the
plate, which plate can be adjusted nearer to or farther from the excentric by
means of the bolts and nuts screwed into the box f.
The india-rubber buffers are placed between the ion plates h, j, in the
box in order to obtain an equal pressure on the fixed rolls from both sides
of the adjustable rolls, and the bolts g with double nuts are intended to allow
accurate adjusting, see Figure V. and IX. The rubber buffer also serves for
producing an elastic pressure on the levers, and by screwing up or down the
bolts g, according to the work required, the pressure on the buffers, and, through
them, on the levers and the rolls can be increased or decreased at pleasure.
I may here remark that both the levers e of one side sit on one and the same
shafts, as shown in Figures V. and VI.

page_text: The toothed wheel o, pinion p, and crank t are designed to obtain a greater
pressure through the excentric.
In order to crush the materials, especially semolina, or middlings, or sharps,
down to smaller sizes, and then to grind these down into coarse flour, the levers
are furthermore provided with screws u, which can be set by nuts adapted in
the levers, and which screws u press against a head won the bearings in the
standards or brackets, as shewn in Figures V., VI. These screws are for the
purpose of setting the adjustable rolls perfectly parallel to the fixed rolls, an
operation to be executed in the following manner:-A piece of paper, sheet
iron, or the like is placed between the rolls, and the screws u are adjusted on
the right and left until the sheet sits even between the rolls, and then the
nuts screwed up tight till the screws u are fast in the lever c. After this
setting, adjusting, or regulating, the hand y, which is moveable on the screw u,
is set up by means of the two nuts z, z, to the point marked 0 (zero) on the
graduated scale a', which is graduated to shew the distance between the rolls in
half millimeters.
Whenever a greater distance between the rolls is required for the class of
work, the screw u can be more or less set up, and the pointer on this screw will
then point to the corresponding degree on the scale or index a¹.
A small deviation or wearing of the bearings can be compensated in the
manner described before.
A pointer and graduated index or scale is arranged on each of the four
adjustable bearings.
The bearings of the roll shaft are self-oiling, and constructed so that they
raise the oil in the bearing box by means of a disk c upwards, and deposit it
between shaft and bearing, as shewn in Figure VI, VIII., X. A scraper or
knife is arranged in the upper part of the box to ensure depositing the oil
between shaft and bearing, as shewn in Figure X. By this arrangement the
running hot of the bearings is prevented and a saving of 90 per cent. in oil effected.
All the rolls are made of chilled cast iron, by preference, but glass or other
brittle material may be also used in the described constructions, and similar
constructions can be used for mills with single pairs of rolls.
Having thus fully described the said Invention, as communicated to me by
my foreign correspondent, and the manner of performing the same, I wish it
understood that I claim,-
First. The general arrangement and construction of roller mills for grinding,
essentially as described.
Second. The arrangements for setting the axes of the rolls so as to be able to
vary the same horizontally for the purpose of attaining a required greater or
less pressure of the rolls on one another, as described.
Third. The arrangements for adjusting the brackets and setting the bolts n
and the set screws, as described.
Fourth. The arrangements for drawing the rolls apart or together by means of
excentrics, and the use of excentrics as means for exerting pressure, as described.
Fifth. The arrangements of rolls set at an angle to each other, whereby the
crushed grain can be made to pass twice through rolls at a single feeding, as
described.
Sixth. The arrangements for producing a greater or less pressure by a
greater or less adjustment of the centers of the rolls d and f from or towards
the lines o, k, as described.
Seventh. The arrangements for displacing the brackets and
the bolts and the set screw, as described.
r, and adjusting
Eighth. The arrangements for drawing apart the rolls by means of the
excentric 7, as described.
Ninth. The peculiar arrangement of the lever mechanism, as described, and
shewn in the Drawings.

page_text: Tenth. The set wedges o with graduated scale p, as described, and shewn in
the Drawings
Eleventh. The arrangements for regulating by means of the set screws and
excentrics, as described, and shewn in the Drawings.
Twelfth. The peculiar construction of the set screws u with graduated scale,
as described, and shewn in the Drawings.
Thirteenth. The peculiar construction of the lever e with india-rubber and
excentric pressure mechanism, as described, and shewn in the Drawings.
Fourteenth. The self-oiling bearings with guide, as described and shewn in
the Drawings, and for the purpose specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty-eighth day of February, in the year of our
Lord One thousand eight hundred and seventy-eight.
W. ROBT. LAKE. (L.S.)