'IMPROVEMENTS IN FLOUR MILLS
Year: 1877

page_text: LETTERS PATENT to Carl Pieper, of Dresden, Saxony, for the Invention of
"
'IMPROVEMENTS IN FLOUR MILLS." A communication from Gustave Daverio,
of Oberstrass, near Zürich, Switzerland.
Sealed the 5th April 1878, and dated the 8th October 1877.
PROVISIONAL SPECIFICATION left by the said Carl Pieper at the Office
of the Commissioners of Patents on the 8th October 1877.
CARL PIEPER, of Dresden, Saxony. "IMPROVEMENTS IN FLOUR MILLS." A
communication from Gustave Daverio, of Oberstrass near Zürich, Switzerland.
This Invention relates to that class of flour mills in which the corn is ground
between rollers. Its object in the first instance is, to, reduce the pressure on the
journals of the rollers, and in the second so to arrange the channels for the corn
and the flour as to allow two separate grinding processes to be carried on between
three rollers. For this purpose rope pulleys are keyed on both ends of the shafts of
the upper and the lower rollers, which pulleys have a number of grooves on their
periphery. Above each pair of the said pulleys an expanding pulley is placed
turning on a pivot which is fixed to a sliding piece acted upon by a weighted lever.
A rope is coiled around each of the first-described pairs of pulleys in as many coils
as there are 'grooves in them, and is finally led over the expanding pulley after
the ends of the same have been spliced together. The rope being drawn tight by
the action of the weighted lever, the pulleys on the roller shafts are forcibly drawn
towards each other in a similar manner as a pair of tackle blocks, whereby the
pressure of the journals is almost entirely taken off from the bearings, the strain of
the rope however causing the necessary amount of pressure between the rollers.
As to the second part of the Invention, the grain is conducted from the hopper by
one channel between the upper and the middle roller, and by another between the
latter and the lower roller. Between the second channel and the middle roller a
worm or creeper is placed, which conveys the flour produced by the upper pair of
D

page_text: rollers laterally out of the casing of the mill, so as to prevent it from being mixed
with the grain passing through the second channel.
Instead of using a creeper, a number of small funnel-shaped passages may be made
to traverse the second grain channel by which the flour in that case passes directly
downward.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Carl Pieper in the Greal Seal Patent Office on the 5th April
1878.
CARL PIEPER of Dresden.
" IMPROVEMENTS IN FLOUR MILLS." A communica-
tion from Gustav Daverio, of Oberstrass near Zürich Switzerland.
This Invention relates to the class of flour mills in which the corn is ground
between rollers. Its object in the first instance is, to reduce the pressure on the
journals of the rollers, and in the second, to arrange the channels for the corn and
the flour so as to allow the two separate grinding processes to be carried on between
three rollers. For this purpose rope pulleys are keyed on both ends of the shafts
of the upper and the lower roller, which pulleys have a number of grooves on their
periphery. Above each pair of the said pulleys an expanding pulley is placed
turning on a pivot which is fixed to a sliding piece acted upon by a weighted
lever: A rope is coiled around each of the first-described pairs of pulleys in as
many coils as there are grooves in them, and is finally passed over the expanding
pulley after the ends of the same have been spliced together. The rope being
stretched by the action of the weighted lever, the pulleys on the roller shafts are
forcibly drawn towards each other in a similar manner as a pair of tackle blocks,
whereby the pressure of the journals is almost entirely taken off from the bearings,
the strain of the rope however causing the necessary amount of pressure between
the rollers.
As to the second part of the Invention, the grain is conducted from the hopper by
one channel to the upper and the middle roller, and by another to the latter and
the lower roller. Between the second channel and the middle roller a worm or
creeper is placed by which the flour produced by the upper pair of rollers is con-
veyed laterally out of the casing of the mill, so as to prevent it from being mixed
with the grain passing through the second channel.
Instead of using a creeper, a number of small funnel-shaped passages, by which
the flour passes directly downward may be made to traverse the second grain
channel.
A mill, arranged according to my improved system is represented on the annexed
Sheet 1 of Drawings, Fig. 1 being a vertical cross section, Fig. 2 a sectional
ground plan, Fig. an end elevation and Fig. 4, a side elevation partly in
section.
The Figures 5 and 6 show the modified arrangement respectively in a vertical
cross section and in ground plan.
A is a hopper with the two feed rollers B and C, which are driven by the worms b

page_text: and wheels c, the shaft of the former receiving motion by another worm wheel gearing
from the shaft of the upper roller. D, E, and F, are the three grinding rollers, the
lower one of which revolves by its journals in common fixed bearings K, whilst the
shafts of the rollers D and E turn in bearings K K, which are free to oscillate on
pivots o, o.. M is a common driving pulley. H and H' are the rope pulleys keyed
on the shafts of the rollers D and F, as represented in the Drawing, the lower
pulleys H have six grooves, the upper ones H five, so that there are five coils of
rope around each pair of these pulleys, the sixth coil running from the lower pulley
H' to the expanding pulley I, which must be placed at an angle as shown by the
Drawing. The number of grooves in the pulleys may however be varied according
to desire. The pulley I turns on a pivot fixed to a sliding blocks which works
on a guide bar e. f is a screw passing through a lug on the block 8 and which may
be turned by the wheel h so as to adjust the pulley I with regard to the length
of the driving rope. g is a lever the short forked end of which acts on a washer
under the wheel h whilst its long end carries a weight which determines the tension
required in the rope. Between the bearings, gas tubes p and pl are placed for the
purpose of conducting oil from one bearing to the other and also for shifting the
rollers apart if this is desired. For the latter purpose the tubes have collars on
which the levers k k act, which may be moved by the cams į and the hand lever 7.
This arrangement is made use of when the machine is to be stopped, as thereby
an accumulation of grain before the rollers, which may cause a difficulty in starting
them again, is prevented.
Supposing the weight on each lever g to be 20 lbs., and the proportion of the
lever arms as 1 to 10; the strain on each pulley I will then be 200 lbs. The
tension in each part of the driving rope is therefore 100 lbs., and consequently
the roller D is pressed at either end with a force of 1,000 lbs., the roller F with
a force of 1,200 lbs., against the roller E, the bearings of the rollers D and E
however, are not subject. to any pressure and only serve as guides for the roller
shafts. The upward pull of the two rope parts leading to the pulley I, which
would cause a pressure on the bearing of the roller F is nearly counterbalanced by
the weight of the three rollers, which in a mill carried out on the described
plan, amounted to 340 lbs. The bearings of the roller F are therefore in this
case exposed to a very slight pressure only, which would become zero if
the strain caused by the levers g were made equal to the weight of the three
rollers.
The described arrangement of driving gear may also be applied in case of the
two rollers and for other purposes than the grinding of corn.
The driving ropes must be made of the best hemp, and before using them they
have to be well stretched by a weight equal to about four times their working
strain. It is even preferable to expand the rope by letting it run for some time on
a special machine in which pulleys are arranged in the same style as described for
the mill.
.
For the better preservation of the rope, it is advantageous to impregnate it
with a composition consisting of fish oil, a solution of india-rubber and a small
quantity of rosin, and then to let it dry in the open air.
If it is desired to impart different speeds to the rollers, so as not only to crush
the grains, but to reduce them by a grinding action, this may be attained by
If
making the lower rope pulleys larger in diameter than the upper ones.
corn is to be ground coarsely by grooved rollers, this arrangement is even
necessary, but it may also be used with rollers of porcelain or other material having
a natural roughness of surface for the purpose of producing flour.
The second part of my Invention consists in the arrangement by which two
separate grinding processes may be carried on with three rollers. The corn fed in
from the hopper A by the feed roller B descends through the channel N and is
crushed between the rollers D and E, the resulting meal after being taken off from
the rollers by the scrapers a a, falls through a slite into the tube Q in which a
worm G rotated by the wheels d, d, conveys it towards an opening r, whence it is

page_text: led to the lower part of the mill, to be finally conducted to the dressing machine.
The corn passing over the feed roller C into the channel o' o' for the purpose of
being crushed between the rollers E and F, is thus kept separated from the meal
produced by the rollers D and E. m and n are slides by which an examination of
the space between these rollers and the channel o', o³ is made possible. The mea!
produced between the rollers E and F after being scraped off by the scrapers a¹ a³
is directly conveyed into the dressing machine.
The modified arrangement for keeping the meal produced by the upper rollers
separate from the corn passing through the channel o' o³, is shown by the Figures 5
and 6. A number of funnel-shaped passages a a, in this case travers the said
channel and allow the meal to fall directly into the same conduit towards the
dressing machine as the meal coming from the rollers E F. The upper and
the lower parts of the channel o¹ o³ communicate with each other between
the funnels a a by the spaces B B, which may also be made funnel-shaped at
the top.
By Figures 7 and 8 on Sheet 2, an arrangement of my roller mill is represented in
which the journals D' and F' of the upper and the lower roller revolve in bearings
A and B¹ forming part of the angle levers A and B respectively which have their
fulcrums at H and H. The pressure which the rollers D and F cause upward and
downward, is taken up by the friction rollers L, L' revolving on the pins K K¹.
The brasses J J¹, which serve only to prevent a lateral deviation of the journals D¹
and Fare cut out suitably, so as to allow the rollers L L¹ to come into contact
with the journals. By these rollers the friction is reduced. Supposing, for instance,
the diameter of the roller E to be six times as large as the diameter of the pin K,
(which proportions have been assumed in the Drawing) the power required to
overcome the frictional resistance between the said roller and its pin, will be only
the sixth part G of the power necessary for overcoming the friction which would
otherwise be caused between the journal and its brasses J.
The roller L L¹ are inclosed in the caps or casings a and b respectively, which
are, attached to the corresponding bearings at one end by a hinge, and at the other
by a bolt provided with a washer e of india-rubber. The pressure of the friction
rollers against the journals D¹ and F¹ can be regulated by turning the nuts of the
bolts, the india-rubber washers e (for which steel springs may be substituted)
serving to make this pressure elastic and to allow the rollers to yield in case of
shocks occurring.
U is a bolt passing through the rim of the frame, and through the end of the
lever A, and screwed into the lever B. This bolt is provided with a spring f, which
draws the ends of the levers outward, so as to press the upper and the lower roller
D and F against the centre roller E, as may be seen from the Drawing. The arrange-
ment is of course the same on both sides of the machine.
S is a regulating lever fixed on a small shaft g passing through both frame parts;
on either end of this shaft is keyed an eccentric T bearing against an adjusting
screw in the end of the lever A. By shifting the lever S. the pressure of the rollers
D and F against the roller E may be regulated, or the rollers brought entirely out
of contact with each other.
The center roller revolves at either end in a bearing which may oscillate on a pin
M, the screws h h serving to adjust the bearing in such a manner as to cause the
upper and the lower roller, while being regulated to come into or out of contact
with the center roller at the same moment.
For the purpose of oiling the journals of the upper and the center grinding roller,
small rollers & have been arranged in the corresponding bearings. These rollers dip
into the oil contained in suitable reservoirs in the lower part of the hearings,
and are pressed by springs against the journals so as to rotate with them;
they consequently transfer oil to the journals and thus act as continuous
lubricators.
With regard to the journals of the lower grinding roller, the friction rollers L'
fulfill the same purpose. The pin K is lubricated by a part of the oil taken up

page_text: by the roller L from the journal D', while the roller L' transfers oil directly to its
pin K
The driving power is in this arrangement of roller mill by preference applied to
the center roller E.
:-
The advantages attained by the described improvements are the following:-
1. The speed of the crushing rollers may be increased without danger of a heating
of the bearings, which otherwise very easily occurs in these mills.
--
2. In consequence of the arrangement by which two separate grinding processes
can be carried on by three rollers, the performance of the improved mill is equal to
that of a mill with four rollers of the common system.
3. On account of the great reduction of friction in the bearings and the increase
of performance with regard to the number of rollers, the quantity of meal, &c. pro-
duced is considerably augmented in proportion to the power expended.
Having thus described the nature and object of the said Invention, and the
manner in which it is to be performed or carried out in practice, I hereby declare
that I claim as new and essential features of the same :—
1. In a roller mill having two or three rollers, the combination of the robe
pulleys H and H¹, Figures 23 & 4, having a number of grooves, with an
expanding pulley I, and a corresponding driving rope, as and for the purpose
described.
2. In combination with the three rollers D, E and F, Figures 1 and 2, the two
feed channels N and o¹, o³, and the worm or creeper G, as and for the purpose
described.
3. In combination with the three rollers D, E and F, Figures 5 and 6, the
two feed channels N and o¹o the channel o¹ o' being traversed by the
passages a a leaving between them the passages ẞ B; as and for the purpose
specified.
4. In combination with the rollers D and F, Figures 7 and 8, the bearings
A and B forming part of the angle levers A and B respectively, moreover, the
bolts U, the spring f, and the eccentric T, with lever S, subsequently as described,
and for the purpose specified.
5. The combination of the friction roller L and L¹ with the journals of the
grinding rollers D and F, and with the bearings A¹ and B¹ and levers A and B, as
and for the purpose set forth.
In witness whereof I, the said Carl Pieper, have heremento set my hand
and seal this Twentieth day of March in the year of our Lord One thousand
eight hundred and seventy-eight.
CARL PIEPER. (L.S.)

page_text: Fed 12 January 1883.
TO ALL TO WHOM THESE PRESENTS SHALL COME I CARL PIEPER
formerly of Dresden Saxony now of Berlin in the Empire of Germany send
greeting WHEREAS Her Most Excellent Majesty Queen Victoria by Her Royal
Letters Patent bearing date at Westminster the Eighth day of October in the
year of our Lord one thousand eight hundred and seventy seven in the forty
first year of Her Reign did for Herself Her Heirs and Successors give and Grant
unto me the said Carl Pieper my executors administrators and assigns especial
license full power sole privilege and authority that I the said Carl Pieper my
executors administrators or assigns and every of them by myself and themselves or
by my and their Deputy or Deputies Servants or Agents or such others as I my
executors administrators or assigns should at any time agree with and no others
from time to time and at all times thereafter during the term therein expressed
should and lawfully might make use exercise and vend within the United Kingdom
of Great Britain and Ireland the Channel Islands and Isle of Man an Invention
of "IMPROVEMENTS IN FLOUR MILLS" a communication from Gustave Daverio
of Oberstrass near Zurich Switzerland for and during the term of fourteen years
thence next ensuing And whereas in pursuance and performance of a proviso in
the said Letters Patent contained I the said Carl Pieper did within six calendar
months next after the date of the said Letters Patent cause a Specification in
writing under my hand and seal purporting to particularly describe the nature of
the said Invention and in what manner the same was to be performed to be
duly filed in the Great Seal Patent Office And whereas I have ascertained
tbat the first part of the claims as made in the said Specification relates to matters
of doubtful utility and that others of the claims as inade in the said Specification
are too wide and may be held to comprise matters which extend beyond the
Invention which can be properly claimed under the Grant of the said Letters Patent
and I am therefore desirous of limiting the claims of the said Letters Patent to
the combinations claimed in the second and third claims of the said Specification
NOW KNOW YE that I the said Carl Pieper by and with the leave of Her Majesty's
Attorney General and for the reasons aforesaid do strike out of the Specification
printed by the Queen's Printers and published at the Great Seal Patent Office in one

page_text: thousand eight hundred and seventy eight the words "As to the second part of the
Invention" which occur in line twenty seven of page two of the said printed Copy
of the said Specification-I also strike out the words "second part of my" which
occur in line fifty two of page three of the said printed Copy of the said Specifi-
cation I also insert after the word "declare" which occurs at the end of line
fifteen of page five of the said printed Copy of the said Specification the words.
"that although I have described various arrangements as capable of being used in
carrying out the said Invention yet I lay no claim to any of such arrangements
separately except as hereinafter mentioned but I claim as the Invention secured
to me by the hereinbefore in part recited Letters Patent." I also strike out the
words "that I claim as new and essential features of the same" forming line
sixteen of the said page five. I also strike out the whole of the first and second
claims constituting lines seventeen to twenty three both inclusive on the said page
five I also strike out the numeral "3" which occurs at the commencement of
line twenty four of the said page five. I also strike out the whole of claims four
and five constituting lines twenty eight to thirty four both inclusive of the said
page five of the said printed Copy of the said Specification And in order that
the effect of the said Disclaimer and Memorandum of Alteration may be better
understood I annex hereto a Copy of the said Specification as it will appear when
so altered and amended the Preamble and testing clause being omitted.
This Invention relates to the class of flour mills in which the corn is ground between
rollers. Its object, in the first instance, is to reduce the pressure on the journals
of the rollers; and in the second, to arrange the channels for the corn and the flour,
so as to allow the two separate grinding processes to be carried on between three
rollers. For this purpose rope pulleys are keyed on both ends of the shafts of the
upper and the lower roller, which pulleys bave a number of grooves on their
periphery. Above each pair of the said pulleys an expanding pulley is placed
turning on a pivot which is fixed to a sliding piece acted upon by a weighted lever.
A rope is coiled around each of the first-described pairs of pulleys in as many coils
as there are grooves in them; and is finally passed over the expanding pulley
after the ends of the same have been spliced together. The rope being stretched
by the action of the weighted lever, the pulleys on the roller shafts are forcibly
drawn towards each other in a similar manner as a pair of tackle blocks whereby
the pressure of the journals is almost entirely taken off from the bearings the strain
of the rope however causing the necessary amount of pressure between the rollers.
The grain is conducted from the hopper by one channel to the upper and the
middle roller, and by. another to the latter and the lower roller. Between the
second channel and the middle roller a worm or creeper is placed, by which the
flour produced by the upper pair of rollers is conveyed laterally out of the casing
of the mill, so as to prevent it from being mixed with the grain passing through
the second channel.
Instead of using a creeper, a number of small funnel-shaped passages by which the
flour passes directly downward may be made to traverse the second grain channel.
A mill arranged according to my improved system, is represented on the annexed
Sheet 1 of Drawings, Figure 1 being a vertical cross section; Figure 2 a sectional
ground plan; Figure 3, an end elevation; and Figure 4 a side elevation, partly in
section.
The figures 5 and 6 show the modified arrangement respectively in a vertical
cross section and in ground plan.
A is a hopper with the two feed rollers B and C which are driven by the
worms band wheels c the shaft of the former receiving motion by another worm
wheel gearing from the shaft of the upper roller; D, E, and F, are the three
grinding rollers, the lower one of which revolves by its journals in common fixed
bearings K', whilst the shafts of the rollers D and E turn in bearings K, K, which
are free to oscillate on pivots o, o; M is a common driving pulley; H and H¹ are
the rope pulleys, keyed on the shafts of the rollers D and F, as represented in the
Drawing; the lower pulleys H³ have six grooves, the upper ones H five, so that

page_text: there are five coils of rope around each pair of these pulleys, the sixth coil running
from the lower pulley H¹ to the expanding pulley I, which must be placed at an
angle as shewn by the Drawing. The number of grooves in the pulleys may
however be varied according to desire. The pulley I turns on a pivot fixed to a
sliding blocks which works on a guide bar e; f is a screw passing through a lug
on the block 8 and which may be turned by the wheel h so as to adjust the
pulley I with regard to the length of the driving rope; 9 is a lever the short
forked end of which acts on a washer under the wheel h whilst its long end carries
a weight which determines the tension required in the rope. Between the bearings,
gas tubes
and p' are placed for the purpose of conducting oil from one bearing to
the other, and also for shifting the rollers apart, if this is desired. For the latter
purpose the tubes have collars ou which the levers k, k, act which may be moved
by the cams and the hand lever l. This arrangement is made use of when the
machine is to be stopped as thereby an accumulation of grain before the rollers
which may cause a difficulty in starting them again is prevented.
Supposing the weight on each lever g to be 20 lbs and the proportion of the
lever arms as 1 to 10, the strain on each pulley I will then be 200 lbs. The
tension in each part of the driving rope is therefore 100 lbs and consequently the
roller D is pressed at either end with a force of 1,000 lbs., the roller F with a force
of 1,200 lbs against the roller E; the bearings of the rollers D and E however are
not subject to any pressure and only serve as guides for the roller shafts. The
upward pull of the two rope parts leading to the pulley I, which would cause a
pressure on the bearing of the roller F, is nearly counterbalanced by the weight of
the three rollers, which in a mill carried out on the described plan amounted to
340 lbs. The bearings of the roller F are therefore in this case exposed to a very
slight pressure only, which would become zero if the strain caused by the levers g
were made equal to the weight of the three rollers.
The described arrangement of driving gear may also be applied in case of the
two rollers and for other purposes than the grinding of corn.
The driving ropes must be made of the best hemp, and before using them
they have to be well stretched by a weight equal to about four times their
working strain. It is even preferable to expand the rope by letting it run for
some time on a special machine in which pulleys are arranged in the same style
as described for the mill.
For the better preservation of the rope, it is advantageous to impregnate it
with a composition consisting of fish oil, a solution of india rubber and a small
quantity of rosin, and then to let it dry in the open air.
If is is desired to impart different speeds to the rollers so as not only to crush
the grains, but to reduce them by a grinding action, this may be attained by
making the lower rope pulleys larger in diameter than the upper ones.
If corn is
to be ground coarsely by grooved rollers this arrangement is even necessary, but it
may also be used with rollers of porcelain or other material having a natural
roughness of surface for the purpose of producing flour.
The Invention consists in the arrangement by which two separate grinding
processes may be carried on with three rollers. The corn fed in from the hopper A
by the feed roller B descends through the channel N, and is crushed between the
rollers D and E; the resulting meal after being taken off from the rollers by the
scrapers a, a, falls through a slit into the tube Q in which a worm G rotated by
the wheels d d conveys it towards an opening r, whence it is led to the lower
part of the mill to be finally conducted to the dressing machine. The corn
passing over the feed roller C into the channel o¹, o³, for the purpose of being
crushed between the rollers E and F, is thus kept separated from the meal pro-
duced by the rollers D and E; m and n are slides by which an examination of the
space between these rollers and the channel o' o is made possible. The meal
produced between the rollers E and F after being scraped off by the scrapers a¹ a¹
is directly conveyed into the dressing machine.
The modified arrangement for keeping the meal produced by the upper rollers

page_text: separate from the corn passing through the channel o' o³ is shown by the Figures 5
and 6. A number of funnel shaped passages a a in this case traverse the said
channel and allow the meal to fall directly into the same conduit towards the
dressing machine as the meal coming from the rollers E, F. The upper and the
lower parts of the channel o' o communicate with each other between the
funnels aa by the spaces B B which may also be made funnel shaped at the top.
By Figures 7 and 8 on Sheet 2 an arrangement of my roller mill is represented
in which the journals D¹ and F¹ of the upper and the lower roller revolve in
bearings A and B' forming part of the angle levers A and B respectively which
have their fulcrums at H and H'. The pressure which the rollers D and F cause
upward and downward is taken up by the friction rollers L L¹ revolving on the
pins K K'. The brasses J, J', which serve only to prevent a lateral deviation of
the journals D' and F¹, are cut out suitably so as to allow the rollers L L' to come
into contact with the journals. By these rollers the friction is reduced. Supposing
for instance the diameter of the roller L to be six times as large as the diameter
of the pin K (which proportions have been assumed in the Drawings) the power
required to overcome the frictional resistance between the said roller and its pin
will be only the sixth part of the power necessary for overcoming the friction
which would otherwise be caused between the journal and its brasses J.
The rollers L L are inclosed in the caps or casings a and b respectively, which are,
attached to the corresponding bearings at one end by a hinge and at the other
by a bolt provided with a washer e of india rubber. The pressure of the friction
rollers against the journals D¹ and F¹ can be regulated by turning the nuts of the
bolts, the india rubber washers e (for which steel springs may be substituted)
serving to make this pressure elastic and to allow the rollers to yield in case of
shocks occuring.
U is a bolt passing through the rim of the frame and through the end of the
lever A and screwed into the lever B. This bolt is provided with a spring f
which draws the ends of the levers outward so as to press the upper and the lower
roller D and F against the centre roller E as may be seen from the Drawing. The
arrangement is of course the same on both sides of the machine.
S is a regulating lever fixed on a small shaft g passing through both frame
parts; on either end of this shaft is keyed an eccentric T, bearing against an
adjusting screw in the end of the lever A. By shifting the lever S the pressure
of the rollers D and F against the roller E may be regulated or the rollers brought
entirely out of contact with each other.
The centre roller revolves at either end in a bearing which may oscillate on
a pin M, the screws h h serving to adjust the bearing in such a manner as to cause
the upper and the lower roller while being regulated to come into or out of contact
with the centre roller at the same moment.
For the purpose of oiling the journals of the upper and the centre grinding
roller, small rollers d have been arranged in the corresponding bearings. These
rollers dip into the oil contained in suitable reservoirs in the lower part of the
bearings, and are pressed by springs against the journals so as to rotate with
them; they consequently transfer oil to the journals and thus act as continuous
lubricators.
With regard to the journals of the lower grinding roller the friction rollers L¹
fulfill the same purpose. The pin K is lubricated by a part of the oil taken up by the
roller L from the journal D¹ while the roller L' transfers oil directly to its pin K'.
The driving power is in this arrangement of roller mill by preference applied
to the centre roller E.
=
The advantages attained by the described improvements are the following:
1 The speed of the crushing rollers may be increased without danger of a
beating of the bearings which otherwise very easily occurs in these mills.
2. In consequence of the arrangement by which two separate grinding processes
can be carried on by three rollers the performance of the improved mill is equal to
that of a mill with four rollers of the common system.

page_text: 3. On account of the great reduction of friction in the bearings and the increase
of performance with regard to the number of rollers the quantity of meal &°
produced is considerably augmented in proportion to the power expended.
Having thus described the nature and object of the said Invention and the
manner in which it is to be performed or carried out in practice I hereby declare
that although I have described various arrangements as capable of being used in
carrying out the said Invention yet I lay no claim to any of such arrangements
separately except as hereinafter mentioned but I claim as the Invention secured to
me by the hereinbefore in part recited Letters Patent
In combination with the three rollers D, E, and F, Figures 5 and 6, the two
feed channels N and o¹, o³, the channel o', o, being traversed by the passages a a
leaving between them the passages B B as and for the purpose specified.
In witness whereof I the said Carl Pieper have to this my Disclaimer set my
hand and seal this eighttenth day of December in the year of Our Lord
One thousand eight hundred and eighty one
CARL PIEPER (L.S.)
To the Commissioners of Patents for Inventions
I hereby grant my Fiat giving leave to the above named Carl Pieper, to
file in the Office of the Commissioners of Patents for Inventions with the
0 Specification to which the same relates, the above written Disclaimer and
Memorandum of Alteration. Dated this 11th day of January One thousand eight
hundred and eighty three.