IMPROVEMENTS IN OR RELATING TO ROLLER MILLS FOR GRINDING
Year: 1883

page_text: LETTERS PATENT to William Phillips Thompson of the Agency for Foreign
Patent Solicitors 6 Lord Street Liverpool in the County of Lancaster for an
Invention of IMPROVEMENTS IN OR RELATING TO ROLLER MILLS FOR GRINDING
a communication from Daniel E Dowling a resident of the City, county and
State of New York, United States of America
PROVISIONAL SPECIFICATION left by the said William Phillips Thompson
at the Office of the Commissioners of Patents on the 5th December 1883.
WILLIAM PHILLIPS THOMPSON of the Agency for Foreign Patent Solicitors
6 Lord Street Liverpool in the County of Lancaster " IMPROVEMENTS IN OR
RELATING TO ROLLER MILLS FOR GRINDING [a communication from Daniel
E Dowling a resident of the City, county and State of New York, United States
of America]
The aim of this invention is to provide a means whereby middlings and similar
grain products may be delivered between the grinding rolls of roller mills in a .
constant and uniform manner-In the art of milling as carried on at the present
day it is the general custom to reduce middlings and similar materials., the result of
previous reductions of the grain, by passing the same between paralell rolls, the
surfaces of which travel in close proximity to each other-In order to secure a
uniform reduction of the material and consequently a uniformity in the character
of the product, it is absolutely necessary that the material shall be fed between the
two rolls in an unbroken sheet or stream extending from one end of the rolls to
the other All means bitherto employed for the purpose have failed to secure the
desired result in a satisfactory manner.
In practice it has been found that owing to the varying conditions of the
material as regards its humidity, and the proportion of glutnous matter contained
therein, and the varying conditions of the atmosphere the material will at one
time feed or flow with great freedom while at other times it will have a tendency
to be computed and to be compacted and to resist all attempts which may be made
to cause its delivery in the form of a sheet-The result is that in all known in the
D .

page_text: art up to the present day the centre is delivered from the hoppen between the rolls
or in an irregular or uneven manner-the delivery being more rapid at one time than
at another and the delivery frequently ceasing at one point in the length of the
rolls or at one end of the rolls while it continues at the opposite end. Inasmuch as
the rolls are always urged toward each other by means of springs, weights or
equivalent pressure devices adjusted to secure the proper grinding action-when a
uniform feed occurs from end to end of the rolls it follows that whenever the feed
ceases or diminishes at one end of the rolls only the rolls will be urged nearer
together at that end than at the other, thus producing a varying space or distance
between the rolls from one end to the other, and consequently causing the material
to be reduced unequally or to different degrees of fineness at different points.
Again the cessation of the feed for a portion of the length of the rolls causes the
entire strain of the pressure devices to be exerted upon a comparatively small
surface, or upon a comparatively small amount of material, thus subjecting
the same to an excessive pressure whereby the quality is impaired. Again, a
diminished feed resulting in a diminished resistance to the rolls, their speed is
liable to increase beyond the desired limit and thus exert an injurious influence
upon the material.
It is to avoid all the above mentioned difficulties and secure under all circum-
stances and conditions which are encountered in practice a uniform delivery of the
material between the rolls from one end to the other that my invention is designed.
To this end the invention consists essentially in the combination with two grinding
rolls of a feed hopper extending from end to end above the same, a feed roll located
beneath the mouth of the hopper and above the grinding rolls and an agitator
located within the hopper and provided with teeth or fingers arranged to reciprocate
immediately above the surface of the feed roll and lengthwise of the surface thereof
The feed roll receives a constant forward rotation so that it tends to deliver the
material through the throat or outlet of the hopper while at the same time the
longitudinal reciprocating agitator serves to loosen and disintegrate the material
and distribute the same in a free condition upon the surface of the feed roll in such
a manner that its delivery from the hopper is effected in a thin continuous sheet
which is delivered from the surface of the feed roll directly to the surface of the
grinding rolls thereunder.
The invention also consists in certain minor features of construction which will
be hereinafter explained.
As regards the construction of the grinding rolls their arrangement in relation to
each other and the construction and arrangement by which their adjustment is
secured and their rotation effected, they may be of any usual character a great
number being familiar to all persons skilled in the art.
The feed hopper is located at the top of the frame above the grinding rolls, and
the horizontal feed roll located between the mouth or outlet of the hopper.
The feed roll is constructed with a smooth or substantially smooth surface, and
arranged so that it may be revolved by suitable gearing so as to carry-its upper
surface outward beneath the feed throat or opening in the side of the hopper, for
the purpose of delivering the material from the hopper through said opening and
effecting its discharge directly downward between the grinding roll-The side of
the hopper is provided with a vertically movable gate connected to an adjusting
screw by means of which it may be raised or lowered so as to diminish the width
of the throat or outlet opening above the surface of the feed roll. Special care is
to be observed in constructing the parts that an unbroken throat or opening shall
extend between the edge of the gate and the surface of the feed roll only in order
that a continuous or unbroken sheet of material may escape and be carried outward
on the surface of the roll in that side, while the escape of the material on the
opposite side which lies close to the roll is prevented.
Within the hopper above the feed roll and parallel therewith I count a non-
rotating bar or rod arranged in such manner that it may be reciprocated endwise.
or, in other words in the direction of the axis of the feed roll, This bar which

page_text: may be operated by any suitable means is preferably provided with a depending
arm the lower end of which engages in a sinous slot in a wheel or hub secured to
the journal of the feed roll. This arrangement imparts a reciprocating motion
from the rotary feed roll to the non rotating bar is provided with a series of
depending teeth or fingers, the lower ends of which terminate in close proximity to
the upper surface of the roll, in or near the outlet throat, these feed figures are
preferably constructed of wire or other elastic material-It is preferred to construct
them in pairs by bending elastic wires into a form and to insert them through
holes in the bar from the upper side and secure them therein by means of a plate
applied above them and fastened in place by screws or bolts. This construction
admits of the teeth which may become broken or bent being readily removed and
replaced by others.
The essential feature of the invention consists as before indicated in combining
with two grinding rolls, and immediately above the same, the feed roll, the hopper.
and the agitors moving lengthwise above the feed rolls.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and of
an Order of the Lord Chancellor filed by the said William Phillips Thompson
in the Patent Office on the 23rd June 1884.
WILLIAM PHILLIPS THOMPSON of the agency for Foreign Patent Solicitors
6, Lord Street, Liverpool in the County of Lancaster "IMPROVEMENTS IN OR
RELATING TO ROLLER MILLS FOR GRINDING" A communication from Daniel
E. Dowling, a resident of the city, county and state of New York, United States
of América
The aim of this invention is to provide a means whereby middlings and similar
grain products may be delivered between the grinding rolls of roller mills in a
constant and uniform manner. In the art of milling as carried on at the present
day it is the general custom to reduce middlings and similar materials, the result
of previous reductions of the grain, by passing the same between parallel rolls, the
surfaces of which travel in close proximity to each other. In order to secure a
uniform reduction of the material and consequently a uniformity in the character
of the product, it is absolutely necessary that the material shall be fed between the
two rolls in an unbroken sheet or stream extending from one end of the rolls to
the other. All means hitherto employed for the purpose have failed to secure the
desired result in a satisfactory manner.
In practice it has been found that owing to the varying conditions of the material
as regards its humidity, and the proportion of glutinous matters contained therein
and the varying conditions of the atmosphere the material will at one time feed
or flow with great freedom, while at other times it will have a tendency to become
compacted and to resist all attempts which may be made to cause its delivery in
the form of a sheet. The result is that in all mills known in the art up to the
present day the material is delivered from the hopper between the rolls in an
irregular or uneven manner the delivery being more rapid at one time than
at another and the delivery frequently ceasing at one point in the length of the
rolls or at one end of the rolls while it continues at the opposite end. Inasmuch as
the rolls are always urged toward each other by means of springs, weights or
equivalent pressure devices adjusted to secure the proper grinding action when a
uniform feed occurs from end to end of the rolls, it follows that whenever the feed
ceases or diminishes at one end of the rolls only the rolls will be urged nearer
together at that end than at the other thus producing a varying space or distance
between the rolls from one end to the other and consequently causing the material
to be reduced unequally or to different degrees of fineness at different points.
Again the cessation of the feed for a portion of the length of the rolls causes the
entire strain of the pressure devices to be exerted upon a comparatively small
surface or upon a comparatively small amount of material, thus subjecting the
same to an excessive pressure whereby its quality is impaired. Again, a diminished
feed resulting in a diminished resistance to the rolls, their speed is liable to
increase beyond the desired limit and thus exert an injurious influence upon the
material.
It is to avoid all of the above mentioned difficulties and secure under all
circumstances and conditions which are encountered in practice, a uniform delivery
of the material between the rolls from one end to the other that my invention is
designed. To this end the invention consists essentially in the combination with
two grinding rolls of a feed hopper extending from end to end above the same, a
feed roll located beneath the mouth of the hopper and above the grinding rolls and
an agitator located within the hopper and provided with teeth or fingers arranged

page_text: to reciprocate immediately above the surface of the feed roll and lengthwise of the
surface thereof. The feed roll receives a constant forward rotation so that it tends
to deliver the material through the throat or outlet of the hopper, while at the
same time the longitudinal reciprocating agitator serves to loosen and disintegrate
the material and distribute the same in a free condition upon the surface of the
feed roll in such a manner that its delivery from the hopper is effected in a thin
continuous sheet, which is delivered from the surface of the feed roll directly to the
surface of the grinding rolls thereunder.
The invention also consists in certain minor features of construction which will
be hereinafter explained.
Referring to the accompanying drawings
Fig. 1 represents a vertical section through the upper portion of the grinding mill -
having the improvement applied thereto.
Fig. 2 is a longitudinal vertical section of the same in line with the axis of
the roll.
As regards the construction of the grinding rolls, their arrangement in relation to
each other, and the construction and arrangement by which their adjustment is
secured and their rotation effected, they may be of any usual character, a great
number being familiar to all persons skilled in the art.
Referring to the drawings:
AA, represent two co-operative grinding rolls; B, the frame or body of the
machine in which the rolls are mounted, C, the feed hopper located at the top of
the frame above the grinding rolls; and D a horizontal feed roll located beneath
the mouth or outlet of the hopper.
"
:
As shown in the drawings, the feed roll is constructed with a smooth or'
substantially smooth surface, and arranged so that it may be revolved by suitable
gearing so as to carry its upper surface outward beneath the feed throat or
opening a in the side of the hopper, for the purpose of delivering the material from:
the hopper through said. opening and effecting its discharge directly downward
between the grinding rolls. The side of the hopper is provided with a vertically
movable gate K, connected to an adjusting screw by means. of which it may be
raised or lowered so as to diminish the width of the throat or outlet opening above
the surface of the feed roll. Special care is to be observed in constructing the parts
that an unbroken throat or opening shall extend between the edge of the gate and
the surface of the feed roll on the delivery side only in order that a continuous or
unbroken sheet of material may escape and be carried outward on the surface of
the roll on that side, while the escape of the material on the opposite side which
lies close to the roll is prevented.
Within the hopper above the feed roll and parallel therewith a non-rotating bar
or rod F is mounted, arranged in such manner that it may be reciprocated endwise
or, in other words, in the direction of the axis of the feed roll. This bar, which
may be operated by any suitable means is preferably provided with a depending
arm I, the lower end of which engages in a sinuous slot in a wheel or hub J
secured to the journal of the feed roll. This arrangement imparts a reciprocating
motion from the rotary feed roll to the bar F provided with a series of depending
teeth or fingers, the lower ends of which terminate in close proximity to the upper
surface of the roll, in or near the outlet throat as plainly represented in both
figures. These feed fingers are preferably constructed of wire or other elastic
material. It is preferred to construct them in pairs by bending elastic wires into
a form, and to insert them through holes in the bar F, from the upper side and
secure them therein by means of a plate G, applied above them and fastened in
place by screws or bolts H. This construction admits of the teeth which may
become broken or bent being readily removed and replaced by others.
The essential feature of the invention consists, as before indicated, in combining
with two grinding rolls, and immediately above the same, the feed roll, the hopper,
and the agitators moving lengthwise above the feed roll. I am aware that a
feed roll has been combined with rotary agitators above the same, and with

page_text: agitators arranged to vibrate in planes transverse to the axis of the said roll; and
also that spiral agitators or screws, have been arranged above the surface of a feed
roll in a grinding mill; and to such combinations no claim is laid. In practice it
has been found that they fail to secure that uniformity of feed upon the rolls
which is attained by the peculiar combination constituting the subject of the
invention.
Having thus described the invention as communicated to me I wish it to be
understood that what I believe to be new and claim is :-
1st A roller griding mill provided with feed mechanism substantially as
described.
2nd As an improvement in roller grinding mills the combination of two grinding
rolls, a rotary feed roll extending lengthwise above the same, a hopper located
above the feed roll and having at one side only a feed throat or passage above
the roll, an agitator located within the hopper and provided with teeth terminating
near the upper surface of the feed roll, and mechanism for reciprocating said
agitator lengthwise of the feed roll.
3rd The improved grinding mill consisting of the two co-operating rolls, the
rotary feed roll, the hopper having on one side an outlet between its lower
edge and the feed roll the vertically adjustable gate to control said outlet, the
feed bar provided with depending teeth above the feed roll and means of
reciprocating said bar lengthwise of said roll.
4th The combination of the two grinding rolls, the feed roll, the gate and the
agitator bar centrally located within the hopper and provided with teeth
terminating at or near the feed throat, and means for reciprocating said bar
endwise
In witness whereof I, the said William Phillips Thompson have hereunto set
my hand and seal this nineteenth day of June in the year of our Lord one
thousand eight hundred and eighty four