IMPROVEMENTS IN MILLS OR APPARATUS FOR GRINDING OR REDUCING GRAIN, SEEDS. OR OTHER GRANULAR SUBSTANCES
Year: 1874

page_text: LETTERS PATENT to John Groig and Charles Spinks, of Leith, in the
County of Mid Lothian, North Britain, for the Invention of
"IMPROVEMENTS IN MILLS OR APPARATUS FOR GRINDING OR REDUCING GRAIN,
SEEDS. OR OTHER GRANULAR SUBSTANCES.”
PROVISIONAL SPECIFICATION left by the said John Greig and Charles
Spinks at the Office of the Commissioners of Patents, with their
Petition, on the 3rd December 1874.
We, JOHN GREIG and CHARLES SPINKS, of Leith, in tho County of
Mid Lothian, North Britain, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MILLS OR APPARATUS FOR GRINDING OR
REDUCING GRAIN, SEEDS, OR OTHER GRANULAR SUBSTANCES," to be as follows,
that is to say: -
This Invention has for its object the constructing of mills or grinding
apparatus in an improved manner, and so as to work more effectively,
economically, and satisfactorily than existing mills.
In one modification the improved apparatus comprises a cylindrical or
slightly tapered case of cast iron or other suitable materials fixed in an

page_text: inclined position, and having within it a cylindrical or slightly tapered
drum. A number of strips of steel are fixed in grooves in the internal
surface of the case and in the external surface of the drum, and the
surfaces of these steel strips are roughened or dressed like the grinding
surfaces of millstones or in any other suitable way. The drum is fixed
on a shaft, by means of which it is made to revolve by steam or other
motive power, and the grain or substances to be ground being admitted
by a feed hopper into the upper end of the casing become ground between
the roughened surfaces, and are finally delivered at the lower end of the
casing. The drum does not present a complete cylindrical surface, but
las portions cut away at two or more parts, which causes it to act as a
fan and drive air between the grinding surfaces so as to keep them cool.
When the drum and casing are made with a slight taper the distance
between the grinding surfaces can be adjusted by means of a screw acting
on the end of the shaft. The feed hopper is fitted with a fluted roller,
which being turned continuously at a suitable rate causes the grain or
substances to be fed in regular and continuous manner.
The machine may be placed vertically, horizontally, or at any inter-
mediate inclination, and the casing might be made to revolve over a
stationary drum, or the casing and drum may be made to revolve in
opposite directions.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Greig and Charles Spinks in the Great
Seal Patent Office on the 2nd June 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
GREIG and CHARLES SPINKS, of Leith, in the County of Mid Lothian,
North Britain, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of December, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said John Greig and Charles Spinks, Her
special licence that we, the said John Greig and Charles Spinks,
our executors, administrators, and assigns, or such others as we, the said

page_text: John Greig and Charles Spinks, our executors, administrators, and
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 for "IMPROVEMENTS IN MILLS OR APPARATUS FOR
GRINDING OR. REDUCING GRAIN, SEEDS, OR OTHER GRANULAR SUBSTANCES," upon
the condition (amongst others) that we, the said John Greig and
Charles Spinks, our executors or administrators, by an instrument in
writing under our, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that we, the said John Greig and Charles Spinks, do
hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement in writing, reference being had
to the accompanying Drawings, that is to say :-
-
Our said Invention has for its object the constructing of mills or
grinding apparatus in an improved manner, and so as to work more
effectively, economically, and satisfactorily than existing mills.
And in order that our said Invention and the manner of performing
the same may be properly understood, we hereunto append a Shect
of explanatory Drawings, to be herein-after referred to, and representing
a grinding mill as made with our improvements. In these Drawings the
same reference. numerals are used to mark the same or like parts
wherever they are repeated.
Figure 1 of the Drawings is a vertical longitudinal section of the mill,
and Figure 2 is a sectional end elevation.
·Figure 3 is an enlarged transverse vertical section, and Figures 4 and 5
are sections of certain steel strips or plates used in the construction of
the mill.
The apparatus is carried by four pillars 1, 2, 3, 4, bolted down on a
base plate and foundation 5, and it comprises a cast-iron case 6, which
may be either tapered as shown or cylindrical. The case 6 is for con-
•

page_text: venience cast in two halves, which are bolted together by means of
longitudinal flanges at the sides, and the ends of the case are bolted by
means of flanges to rings 7, 8, which are bolted to the pillars 1, 2, 3, 4,
by means of wing flanges. Within the case 6 there is a drum 9, which
is tapered or cylindrical accordingly as the case is, and this drum 9 is
fixed on a shaft 10, which has also fast on it a pulley 11 to receive a
driving belt from a suitable revolving shaft. A number of strips or
plates 12 of steel arc fixed in longitudinal dovetail grooves formed in the
internal surface of the case 6, and similar steel strips or plates 13 are
fixed in longitudinal dovetail grooves formed in the external surface of
the drum 9. These steel strips 12, 13, are roughened or dressed
like the grinding surfaces of millstones, or in any other suitable way.
We prefer to form the steel strips 12 of the case 6 with longitudinal
grooves, as shown in cross section in Figure 4, and those 13 of the
drum 9, with grooves such as are shown in cross section in Figure 5, but
inclined at an angle of about fifteen degrees of the circle from the
longitudinal line. The grain or substances to be ground are admitted
from a hopper 14 by a duct 15 entering the case 6 at its upper side near
its smaller end, and getting in between the case 6 and the drum 9 become
ground between the roughened steel strips 12, 13, and gradually con-
veyed towards the larger end of the case, finally issuing from the lower
part of the case 6 into a duct 16, which leads them to a lower apartment.
The drum 9 does not present a complete cylindrical or convex surface
but is made with flat surfaces 17 at two (or it might be more) parts,
which cause it to act to some extent as a fan, and to drive air between
the grinding surfaces so as to keep them cool.
are by preference also fitted with blades 18 inclined so as to impel
the materials being ground towards the larger end of the case 6. Also
to insure a more effectual cooling and ventilating action by air, air
from a fan or blower is led by a pipe 19 into the smaller end of
the case 6, and the end of the case being closed, and the drum 9 also
having its ends closed, the air thus led in is compelled to pass between
the case 6 and the drum 9. When the drum 9 and casing 6 are made
with a taper, as shown in Figure 1, the distance between the grinding
surfaces can be adjusted by means of a screw 20 carried by a bracket
and bearing against the end of the shaft 10 on which the drum is fixed.
These flat surfaces 17
The duct 15 of the feed hopper is fitted with a fluted roller 21, the

page_text: pulley 23 on the drum shaft 10. The fluted roller 21, which is thus
always driven at a rate uniformly proportional to that of the drum 9, is
placed close to one side of the duct 15, but so as to leave a space at the
other side, and at this latter side, which is the descending side of the
roller, there is a slide valve 24, which is adjustable by means of a screw,
and which regulates conjointly with the action of the roller 21 the
descent of the grain or granular substances.
The machine may be constructed with the shaft 10, drum 9, and
case 6, horizontal, vertical, or at any intermediate inclination, and the
casing might be made to revolve over a stationary drum, or the casing
and drum may be made to revolve in opposite directions.
Having thus particularly described our said Invention and the manner
of performing the same, we have to state that we do not restrict our-
selves to the precise details herein described or delineated, but that what
we believe to be novel and original and claim as the Invention secured
to us by the herein-before in part recited Letters Patent is, the con-
structing of mills or apparatus for grinding, substantially in the improved
manner herein described and delineated.
In witness whereof, I, the said John Greig, on behalf of myself
and the said Charles Spinks, have hereunto set my hand and
scal, this First day of June, in the year of our Lord One
thousand eight hundred and seventy-five.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JOHN GREIG. (L.s.)