IMPROVEMENTS IN ROLLER MILLS
Year: 1881

page_text: 26
LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and
Company, Solicitors of Patents, of 67, Strand, in the City of Westminster,
Civil Engineer, for an Invention of IMPROVEMENTS IN ROLLER MILLS."
A communication from abroad by J. G. Koerner, of Waldenberg, in the
German Empire.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at
the Office of the Commissioners of Patents on the 9th March 1881.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors
of Patents, of 67, Strand, in the City of Westminster, Civil Engineer.
"IMPROVEMENTS IN ROLLER MILLS." A communication from abroad by
J. G. Koerner, of Waldenburg, in the German Empire.
This Invention relates to roller mills, and consists in the following arrangement
and construction of parts:-
The mill has two rollers placed one over the other, the upper roller being fixed
and serving as feed roller, while the lower one is adjustable so as to regulate the
distance between the two.
The bearings of the upper roller are firmly attached to both sides of the frame,
and the bearings of the lower roller are supported by two adjustable transverse levers
secured to the frame, each of these beams or levers being pivoted at one end to a fixed
bolt by means of a bearing open at the bottom and having a steel jaw which rests on
the said bolt, and can be adjusted from the top of the bearing by a set screw 80 as
lift or lower the transverse beam together with the lower roller in order to regulate
the distance between the two rollers. The extremity or front end of the transverse
beam forms a hollow casing open at the bottom and containing a helical spring,
through which passes a screw spindle screwed with its lower end into a nut forming
part of or rigidly fixed to the frame, while the top of the spindle rests on the upper
face of the casing with a boss, and has a small hand wheel for turning the spindle,
which is also provided with a movable nut placed at the bottom of the spring
casing, and serving to regulate the tension of the spring so as to obtain the required
pressure between the rollers. By turning the two hand wheels the minimum

page_text: distance between the rollers can be regulated according to the nature of the
material to be ground by raising or lowering the two transverse beams
independently of each other."
The two spindles may however be connected and turned simultaneously, preferably
by placing at the top of each spindle a worm wheel which gears into an endless
screw mounted on the same driving shaft, which can be turned at the end by a
hand wheel.
The bearings of the lower roller are pivoted on the respective transverse beams,
so that each bearing can turn on an axis perpendicular to the axis of the roller,
besides being movable, together with the beam on a pivotal bolt parallel to the.
axis of the roller. In order to facilitate the lifting of the lower roller for cleaning
the bearings two lugs are cast to the inside of the roller frame projecting under the
roller and forming nuts for set screws. Instead of the latter wedges may be
inserted between the lug and the roller.
The frame of the mill is composed of two stands carrying the roller bearings and
connected with each other by two oblique plates or partitions, serving at the same
time to conduct the product falling from the rollers.
The material is fed to the rollers through a hopper fixed to the top of the frame,
and having on one side a movable slide for regulating the admission of grain, said
slide being moved up and down by means of a horizontal shaft and a handle. For
obtaining the more accurate adjustment two worm wheels are mounted on the
horizontal shaft, which worm wheel can be turned by endless screws.
The tension of the spiral spring (at the end of each transverse beam), and
therefore the pressure of the lower against the upper roller can be regulated by the
temporary application of a registered lever which compresses the spring according
to the position of the movable weight on the lever. Instead of making this weight
movable on the lever it can be replaced by larger or smaller weights, and the same
mode of regulating the pressure of the movable against the fixed roller may be
adapted for roller mills in which the rollers are placed side by side. This pressure
may also be measured by a spring dynamo meter applied to the beam or lever
which carries the roller bearing.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great Seal Patent Office on the-
9th September 1881.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors
of Patents, of 67, Strand, in the City of Westminster, Civil Engineer.
"IMPROVEMENTS IN ROLLER MILLS." A communication from abroad by,
J. G. Koerner, of Waldenburg, in the German Empire.
The roller mill illustrated by the accompanying Drawing is designed to combine
great simplicity and capacity of production, while using but little power and space.
The frame is formed by two standards held together by two traverses h¹, h², and
cast in one piece with the latter. The hopper n is fitted to the standards by
ledges o. In the frame two rollers are mounted laid one above the other. The
upper grinding roller a has a fixed bearing, while that of the lower one b is
movable and can be moved against the upper roller. The bearings c of the upper
roller are firmly attached to the projections on the standards g by means of bolts e.
In the lower part of the standards are the lever arms i, which support the
bearings d of the movable roller b by means of the pivots k, k. The levers i turn
on the bolts fastened in the machine-frame, which arrangement allows of the
lower roller yielding downwards. The journal bearings turning on pivots k, k,
cause the bushes to keep tight to the journals. This mobility of the bearings,
combined with the turning of the lever arm i downwards, causes the movable
roller to yield when hard bodies enter by chance between the rollers. For the same
purpose of yielding the levers i are supported by spiral springs m (detail section,
Fig. 10), the tension of which can be altered inore or less by turning the nuts n¹ of
the regulating springs m to the right or to the left in order to obtain the necessary
pressure of the lower roller against the upper one. For preventing the nuts from
turning spontaneously there is a stop pin g2, which is pressed into recesses of
the nut n¹² by the spring so as to prevent any unintended turning of the nut.
By this arrangement of a fixed upper roller, only the bottom of which comes in
contact with the material to be ground, the journals of the upper-roller suffer
almost no friction at all, the weight of the roller sufficing to disintegrate grains by
riffle rollers and to grind the middlings by smooth rollers. The principle of the
fixed upper roller has also the advantage of allowing an exact regulation of the
distance between the two rollers, because it can be seen through the slit by opening
the doors u, u, and by pulling up the grain conduit slide. In case of alien bodies
being intruded the lower roller yields easily, the pressure of the levers i and of the
springs being overcome. The shaft q, provided with a hand wheel p¹, has its
bearings in the standards y and has the purpose of effecting a regular lifting and
sinking of the levers i and consequently of the movable roller. For that purpose.
the worms j gear into the worm wheels o¹, serving as nuts for the screws m. When
the wheel p¹ and the shaft q¹ begin to turn the two endless screws 8¹ and the
wheels or nuts o' move and the movable roller approaches to and retires from the
fixed one.
The regulating wheels vare intended to regulate exactly the minimum
distance between the rollers, and are placed loose on the spindles m in order to be
taken off after having regulated the distance.
By turning the wheel p¹ the roller b can be raised or lowered, and by turning
the screws m either lever i can be regulated and with them the movable roller b.
The feed of the material can be controlled and adjusted through the slide p running
in slots, either by means of the lever q or by turning the regulating screws a', into
which gear the worm wheels v¹ mounted on the horizontal shaft u¹ (see detail,
Figs. 11 & 12).
The whole feeding arrangement is designed to avoid unequal distribution of the
grain, which, after leaving the slide p and the roller p¹¹, spreads over the slide p³
and falls on the quickly rotating roller b. The standard traverse h¹ (which guides
the grain after having passed through the rollers) is made to project as far as

page_text: practicable; the traverse h², however, is situated deeper in order to allow of easily
directing the ground material and render the control very exact.
The slide (intended to control the inlet) can be swiftly opened and shut by
turning the shaft u' by means of the lever q; the flowing out of the material can
be easily and exactly governed to right or left by means of the screws a¹.
The regulating screw over the fulcrum 1 of arm i is loosely connected with
the cheeks i¹, and the lever i can be raised and lowered by means of the screw 1.
This arrangement allows of the back ends of the levers i being moved, and in
consequence of approaching the lower roller to the fixed upper one, which is
required after the rollers have become smaller by continued use. In flour mills the
grinding may be performed by rollers arranged in pairs and moving against each
other with differential speed.
In order to allow of moving the rollers with more or less speed according to the
material each roller is furnished with a step-pulley moved by pulleys which are
adapted to the proportions of differential speed. The most favorable differential-
speed for rough grinding with riffile rollers is for the first operation about 3: 5,
for middle grinding 1:2, and for final grinding 1:3.
From these conditions there results the following table :—
1
For final grinding (producing flour) with smooth rollers, both rollers must be 25
moved with equal speed when grinding ordinary middlings; for grinding superior
middlings the rollers should move with a differential speed of about 5:6, and for
final grinding, by slower revolution of the rollers, the rollers are also moved at a
proportion of about 5:6; the following table corresponds to these conditions:-

page_text: In order to allow of easily putting the pulleys or wheels on or off, and of their
always running true, the pulleys or wheels are fitted conically on the roller-shafts,
and are kept there by key k² and set screw l².
As above shown by means of suitable step pulley a riffled pair of rollers may be
easily and advantageously used for coarse and fine grinding, and a smooth pair of
rollers for final grinding.
In order to avoid lifting out the rollers for cleaning, on the journals I arrange
lugs z on the inside of the standards, the lugs being furnished with set screws
provided with curved supports. After lifting the rollers by means of screws z,
taking off the pulleys and screws la, la, and slightly screwing back the set screws f₂, f
on the bolts k, k, the bolts k, k, can be pushed back by means of the screws f₂, f
and the bearings taken off.
Figures 4 to show arrangements for obtaining a constantly regulated pressure
of the movable roller against the fixed one. I prefer the mode shown in Figs. 4
and 5, which show a slit or fork arm a, put on the spring-head of lever i, the two
fork-ends being connected by a bolt under the lever i, and thus the fork arm a³ is
fastened to the lever i. By hanging in one of the notches x1, x2, x³, of arm
a³ a weight corresponding to the proportions of levers the pressure is
regulated.
For instance, intending to produce a feeble pressure of the rollers, I put the
weight on notch x and turn the nut n¹ until a sheet of paper could be introduced
between lever i and shoulder w of screw m. Both arms i and as set right, weight c³
and arm a³ are removed and the grinding may begin, the correct pressure having
been thus obtained. The same proceeding is adapted to obtain strong or medium
pressure, but the weight is fixed in different notches.
Figs. 6 and 7 show a weight arm with wrench-shaped end. It can be
fastened to the head, as shown in Fig. 6, or any other point of the movable
arm f³.
Figs. 8 and 9 show the connection of an angular weight-arm and rod k³ with
slides of the movable roller with horizontal arrangement of the rollers. Angle
lever is connected with the two connecting rods ³, clasping the slide 13 with the
bolts m³. The angle lever must touch the standard. By suspending weight g³
the slide is drawn backwards. As stated in describing Figs. 4 and 5, the spring
pressure is correct when the distance between the slide bearing and the contact
screw is just sufficient to pass a sheet of paper through. These arrangements
allow of regulating exactly the movable roller for obtaining the required
nragg11 ro
1. The vertical arrangement of the rollers, of which the upper one is fixed
while the lower one rests on movable axle bearings and levers supported by springs,
substantially as described and illustrated.
2. The universal mobility of the lower roller by turning it on the pivot and
suspension of the roller bearing in the hollow of the lever i through bolts k, k,
secured by set screws, the universal adjustability together with the vertical
arrangement of the wheels v.
3. The arrangement for the universal regulation of the grain regulating slide,
in combination with the advantageous distribution of the grain, and the appliance
for its exact control.
4. The arrangement at the back of the lever i for putting the arms i in a
horizontal position when the rollers are worn and torn.
5. The arrangement of the belt gearing in order to obtain a speed favorable for
grinding, the mounting of the pulleys (or wheels) on the conical end of a shaft in
order to facilitate their being put on and off.
6. In order to clean the journals, the arrangement of the pegs y with screws z

page_text: on the sides of the standard below the rollers, the set screws f2 of the bolts k, k,
intended to facilitate the withdrawal of the bolts k, k.
7. The arrangement for controlling the pressure of the rollers.
The whole substantially as described and illustrated.
In witness whereof, I, the said Herbert John Haddan, have hereunto set 5
my hand and seal, this Nineteenth day of August, A.D. 1881.
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