Year: 1886

page_text: I ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex
Engineer do hereby declare the nature of this invention (a communication from
Ben. Z. Taylor, of the City of Decatur in the County of Macon and State of Illinois,
in the United States of America, Manufacturer) and in what manner the same is
to be performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to granulating rolls and consists in certain details of
construction of said rolls as hereinafter set forth and claimed.
Under the present system of granulating or high milling it has been necessary
to provide a pair of rolls for each "break" in the wheat, from six to eight pairs of
rolls being used to complete the reduction, and it is the object of this invention
to greatly reduce the number of rolls and increase the efficiency of their operation.
In the drawing accompanying and forming a part of this specification the
opposing surfaces of these rolls are shown.
a is a section of a roll having rotation in the direction indicated by the contiguous
arrow, its speed approximating one hundred revolutions per minute.
l is a section of a roll having rotation in the direction indicated by the contiguous
arrow, its speed approximating three hundred revolutions per minute.
Roll a is provided with furrows having the corrugated approximately tangential
surfaces and the abrupt surfaces c approximately radial with the roll.
Roll d is provided with furrows having the corrugated approximately tangential
surfaces e, and the abrupt surfaces f approximately radial with the roll.
The abrupt radial surfaces c of roll a are presented in the direction of the
rotation of said roll.
The abrupt radial surfaces f of roll & are presented in the direction opposed to the
rotation of said roll.
In operation the radial surfaces e act as a positive feed, the grains ordinarily
resting in the deepest part of the furrows close to surfaces c, and as the said grains
pass between the rolls they are subjected to the successive action of several of the
surfaces e. The action of the first surface e will have the effect to break the grain
very slightly and the operation of the succeeding surfaces will continue and
complete the reduction to the capacity of the rolls, as the grains are carried nearer
to roll d. The granulated product of the complete operation presses into the
deepest part of the furrows of roll a, passes roll d and is discharged or fed to
another pair of rolls in any suitable manner.
The inclination of surfaces b together with their rotation, carries the grain
gradually in contact with the more rapidly revolving surfaces e.

page_text: The furrows in roll d are shallower than the furrows in the opposing roll in order
that they may carry no imperfectly reduced grains between the rolls, and are more
numerous in order that the required reductions may be made without an excessive
degree of speed in roll d.
The grain in the furrows of roll a is carried constantly nearer roll d while being
subjected to its action, and a complete operation is effected in each of the furrows
of said roll a, the grain being reduced to a degree equaling the action of from
three to four sets of ordinary rolls.
From the above it will be understood that the grain carried by one furrow of
the slow roll is entirely reduced in said furrow, and that the complete operation of
the rolls is but a repetition of this process in succeeding furrows, each furrow also
effecting its own discharge.
The effect of the construction of the furrows in the different rolls as heretofore
specified and as illustrated in the drawing, is to break the grain instead of to cut
it; and the recesses formed by surfaces b, inclining upwardly and away from roll d,
assist the granulating process by furnishing rotating room for the partially granu-
lated grain.
The corrugations in the furrows are of utility in agitating the particles and
thereby effecting a more thorough granulation, as if the particles are permitted to
lie undisturbed they will become worn by attrition instead of being broken and
granulated.
The result of the above specified operation of my rolls is to procure a quality.
of middlings peculiarly adapted for the finer grades of flour, and to leave the
entire product in an excellent condition for separating and purifying.
The furrows in the fast roll are shown of one half the width and depth of the
furrows in the slow roll, but this proportion may be varied to some extent without
affecting the principle of this invention.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is:
1st. In a roller mill, a pair of opposing rolls having differential rotation in
opposite directions, the slow roll having longitudinal furrows formed each of an
approximately tangential surface longitudinally corrugated, and an abrupt surface
approximately radial with the roll; and the fast roll having longitudinal furrows
formed each of an approximately tangential surface and an abrupt surface
approximately radial with the roll; the furrows in the fast roll approximating in
width and depth to one half the width and depth of the furrows in the slow roll;
the radial surfaces of the furrows of the slow roll being presented in the direction
of the rotation of said roll; and the radial surfaces of the furrows of the fast roll
being presented in the direction opposed to the rotation of said roll.
2nd. In a roller mill, a pair of opposing rolls having differential rotation in
opposite directions each roll having longitudinal furrows formed each of an
approximately tangential surface longitudinally corrugated, and an abrupt surface
approximately radial with its roll; the radial surfaces of the furrows of the slow
roll being presented in the direction of the rotation of said roll; and the radial
surfaces of the furrows of the fast roll being presented in the direction opposed to
the rotation of said roll.