Improvements in Grinding Mills.
Year: 1889

page_text: Date of Application, 23rd Nov., 1889-Accepted, 4th Jan., 1890
COMPLETE SPECIFICATION.
Improvements in Grinding Mills.
I HENRY BIRKBECK of 24 Southampton Buildings Chancery Lane London in the
County of Middlesex Patent Agent (a communication to me from abroad by James
Jones and Aldred James Jones, Millers both of the Town of Thorold in the County
of Welland in the Province of Ontario Canada) do hereby declare the nature of this
invention and in what manner the same is to performed to be particularly described
and ascertained in and by the following statement :--
The object of the invention is to design a roller grinding mill which will produce
the finest grade of middlings in the shortest time and with a minimum of power and
it consists essentially of a longitudinally grooved roller held stationary between two
revolving rollers, one of which has longitudinal ratchet-shaped furrows cut round its
periphery, the said furrowed roller being caused to revolve by acting in conjunction
with the longitudinally grooved roller, and a stationary grooved plate being provided
to grind and regrind the wheat, separating the flour and producing a high grade of
middlings, the bran being reground by being carried between the stationary grooved
roller and the revolving grooved roller located on the side of the stationary roller
opposite to that occupied by the furrowed roller; the whole being otherwise
constructed substantially as hereinafter more particularly explained.
Figure 1, is a cross-sectional elevation, showing the location of the improved
grinding rolls.
Figure 2, is an enlarged perspective detail of the stationary grinding plate.
As I do not claim anything original in the mechanism for driving the grinding
rolls, or the arrangement of hoppers, sieves, etc., which necessarily form a part of, or
operate in conjunction with, a grinding mill it has not been deemed necessary to
illustrate these parts, as everyone familiar with the construction of grinding mills
will, from the description read in conjunction with the accompanying diagram, readily
understand how to adapt this invention to almost any kind of grinding mill.
In the drawing, A, represents a grooved or corrugated roller, which is held in
suitable bearings so that it will remain stationary. We prefer to make from twenty
to thirty-two corrugations to the inch in this roller. B, is a roller having a series of
longitudinal ratchet-shaped furrows made around its periphery, preferably from two
to six to the inch. This roller B is carried in suitable bearings, and is caused to
revolve by any suitable power, which is not necessary to show in this application.
On the opposite side of the roller A, we journal another roller C, and cause it to
revolve by any suitable driving power. The roller C, is grooved or corrugated in a
similar manner to the roller A. D is a grooved or corrugated plate located below the
roller A. E, is a curved perforated skirt or plate extending from the plate D, beyond
the junction of the rollers A and B. F is a spout extending in to the flour hopper,
and having its top side a perforated as indicated. The frames G, in which the
rollers B and C are journaled, are adjustably supported on the table H. It will be
understood that each of the rollers B and C, is provided with two frames G, i.e. one at
each end of each roller. The base of each frame G is provided with a screwed
spindle I, connected to it and the frame of the machine in the ordinary manner to
allow of the easy adjustment of the frames G by merely revolving the spindles I. In
this manner the rollers B and C, may be readily adjusted to suit the class of work
they are intended to perform.
In operation, the grain is first admitted between the stationary roller A and the
revolving ratchet-shaped furrowed roller B. After passing between these rollers it
falls onto the perforated skirt or plate E and the fine flour and middlings fall through
the perforations in the skirt into the flour hopper located below the machine. The
bran and coarser part of the grain falls down the skirt E, and passing between the

page_text: roller B, and the corrugated plate D, is reground, finally falling on to the perforated
top side a of the spont F. The flour and middlings passing through the perforations
in the spout F are conveyed into the flour hopper below the machine, while the bran
falls off the top side a into elevators which convey it back to a point where it may
fall between the corrugated roller C, and the stationary corrugated roller A.
It will thus be seen that by this arrangement of rollers three reductions are
obtained with only two revolving rollers.
The roller A is held in such a manner that when necessary it may be revolved, so
as to bring a different surface opposite to the grinding rolls Band C.
It will of course be understood that instead of the grooved or corrugated rollers a
roller having longitudinal ratchet-shaped furrows may be substituted for either or
both of them.
Having now particularly described and ascertained the nature of this said inven-
tion and in what manner, the same is to be performed, I declare that what I
claim is:
1) In a grinding mill, a revolving roller having longitudinal ratchet-shaped furrows
cut around its surface; substantially as and for the purpose hereinbefore described.
2) In a grinding mill, a revolving roller having longitudinal ratchet-shaped furrows
cut round its surface, in combination with a grooved or corrugated roller B;
substantially as and for the purpose herein before described.
3) In a grinding mill, a revolving roller having longitudinal ratchet-shaped furrows
cut round its surface in combination with a grooved or corrugated roller B, and a
stationary grooved or corrugated plate D; substantially as and for the purpose
herein before described.
4) In a grinding mill a revolving roller having longitudinal ratchet-shaped furrows
cut around its surface, in combination with a grooved or corrugated roller B, a
stationary grooved or corrugated plate D, and a perforated skirt E; substantially as
and for the purpose hereinbefore described.
5) In a grinding mill, a revolving roller having longitudinal ratchet-shaped furrows
cut arround its surface, in combination with a grooved or corrugated roller B, a
stationary grooved or corrugated plate D, a perforated skirt E, and a spout F, having
a perforated side a; substantially as and for the purpose herein before described.
6) In a grinding mill, a stationary grooved or corrugated roller A, in combination
with a revolving roller having longitudinal ratchet-shaped furrows cut in its surface,
and the revolving roller C, having longitudinal grooves or corrugations formed on its
surface; substantially as and for the purpose herein before described.
Dated this 23rd day of November 1889.
TONGUE & BIRKBECK,
34, Sonthampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.