AN IMPROVED PROCESS OF AND MACHINERY FOR GRINDING CORN OR GRAIN.
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office of
the Commissioners of Patents on the 4th February 1881. A communication
from abroad by John Tompkins Noye, Richard Kirby Noye, and Elisha
Haywood Noye, all of Buffalo, New York, United States of America,
Manufacturers of Mill Machinery.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
Agents, Southampton Buildings, London. "AN IMPROVED PROCESS OF AND
MACHINERY FOR GRINDING CORN OR GRAIN.". [A communication from abroad by
John Tompkins Noye, Richard Kirby Noye, and Elisha Hayward Noye, all
of Buffalo, New York, United States of America, Manufacturers of Mill
Machinery.]
This Invention relates to a process of grinding or reducing grain to flour, and to
machinery or apparatus therefor of that class known as roller mills, in which two
or more rolls revolve against each other at different peripheral rates of speed.
The said process consists essentially in passing the grain through a series of sets
of rolls graded in respect to fineness of dress, and through bolts intermediate
between each set and the succeeding set of rolls..
The said machinery or apparatus consists chiefly in the peculiar construction and
arrangement of the grooves and ribs upon the rolls, also in the means whereby
the rolls are adjusted towards and from each other, and in a series of such rolls
graded in respect to fineness or number of grooves to the inch with intermediate
bolts, the several sets acting in succession of grade.
The object aimed at in reducing wheat to flour, is to increase the proportion of
middlings and pure flour, and to leave the bran and germ in a condition most
favorable to their effectual and complete separation from the flour forming
particles. Smooth surfaced rolls flatten the germ and allow the bran to pass in a
coarse unpulverized state, and to this extent accomplish the object; but they also
cause the middlings to cake or form into flakes or thin discs that will not pass
through the meshes of the bolt, and therefore are in the end unsatisfactory.
Grooved rolls having sharp-edged ribs, cut or tear the bran and germ into such fine
particles that a large proportion will pass through ordinary bolting-cloth and
nevitably appear in the middlings and flour.

page_text: This Invention is designed to overcome these objections, and to produce a
machine in which the starch and gluten of the berry shall be properly pulverized
without caking, while the tenaceous portions constituting the husk and germ shall
pass through in a flattened or flaky condition without being much comminuted
thereby greatly increasing the yield of middlings and improving the quality of
flour.
In carrying the said Invention into practice, I provide a frame and two rollers
having their journals supported in bearings resting on the said frame; one bearing
on each side is stationary, and another bearing on each side slides towards and
from the stationary bearings. The sliding bearings may be connected with the
frame by bolts passing through slotted holes in the bearings, or by tongues and
grooves as may be preferred. Adjusting screws work in a threaded lug, secured to
or formed with the frame, and there is a spring surrounding each screw and
bearing with one end against a nut working on the screw, and with the other end
against the sliding bearing so as to press the roller journalled therein towards the
fixed roller. Adjusting screws pass through threaded holes in the sliding bearings
and press against the fixed bearings. These screws are preferably arranged in the
other screws which are made hollow for the purpose. These internal screws
hold the bearings and the rollers journalled therein at a certain minimum
distance apart and prevent the rollers from running in contact with each
other when the machine runs empty. The springs press the rollers against
each other as far as. the screws permit the rollers to approach cach other,
and at the same time permit the movable roller to yield when a hard object of
greater thickness than the material to be reduced enters between the rollers.
A feed hopper of ordinary and well known construction is arranged above the
rollers. The rollers are driven by gear wheels or by pulleys and belts in such
manner that the fixed roller has a greater peripheral speed than the sliding roller.
The rollers are constructed of chilled iron, steel, porcelain, or other hard material.
They are each provided with spiral grooves running in the same direction, and laid
near together. In one form of dress the ribs between the grooves are upon their
advancing sides of easy bevel, and upon the rear side of steeper bevel the points or
edges of the ribs being rounded, and the longer sides of the ribs forming the active
surface. In another form the roller is provided with a dress composed of ribs
rounded equally on both sides, and the contiguous ribs meet at their bases in
sharp angles, while in another form the different ribs composing the dress are of
the form last mentioned but separated at their bases by flat strips, the space
between each pair of ribs being a groove having a flat bottom. The ribs are
preferably applied spirally to both cylinders, the ribs running in the same direction
on both cylinders so that they will cross each other on the contiguous surfaces of
the rollers and therefore cannot intermesh. If desired however the ribs on one of
the cylinders may be arranged parallel with its axis. These rolls operate in a
manner superior to the smooth-surfaced and sharp-ribbed rolls heretofore known,
for, unlike smooth rolls, they do not form the middlings into discs or flakes which
require various and intricate subsequent operations to reduce them to flour, nor do
they cut or tear the bran and germ into fine pieces or particles, as is the case with
sharp-ribbed rolls, but while pulverizing the starch and gluten they simply bruise
and rub the bran and germ, bringing them to, and leaving them in a form which
insures their passage over the tail of the bolt and therefore their elimination from
the middlings and flour.
The dress may vary in number of grooves to the linear inch, and one set of rolls
capable of suitable adjustment will be sufficient for general work; I prefer however
a series of rolls graded in respect to fineness of dress. Each set is composed of two
rolls geared together so as to revolve with differential motion as to their peripheries,
and both rolls of each set have spiral grooves running in the same direction from
left to right. The grooves of the rolls in the first set may number about twenty
to the linear inch, measured circumferentially on the periphery; the grooves of the
rolls in the next set may number about twenty-three to the inch; of the rolls in

page_text: the next set about twenty eight; and of the finishing rolls in the fourth set from
thirty to thirty-two; that is to say, the range of graduation which has been chosen
to illustrate the Invention is from twenty to thirty-two, but the limit admits of
more or less variation in either direction toward or from a dress numbering about
seven or eight grooves to the linear inch.
With wheat and other cereals it will be inadvisable to have more than fifteen
grooves to the inch, at least in the first pair of rolls, and the number of grooves in
any set should never be so great as to cause the ribs to lose their distinctively
rounded character or become so pointed as to cut the bran.
The practical operation is as follows:-
The wheat to be converted into flour is fed into the feed hopper, and passes
thence between the first set of rolls, the product consisting of cracked or partly
crushed wheat, and a considerable quantity of flour is delivered to a bolt, and the
coarser grades and tailings from the bolting operation are carried to the next pair
of rolls which have finer grooves than the first rolls. The product of the said rolls
is in turn passed through a bolt, and so the operation goes on by alternately
cracking, or grinding and bolting through the series of machines until the desired
product has been thoroughly separated from the bran.