AN IMPROVED MILL OR APPARATUS FOR GRINDING PAINTS, COLOURS, MINERALS, AND SIMILAR ARTICLES, AND ALSO FOR GRINDING GRAIN
Year: 1881

page_text: LETTERS PATENT to William Hawley, the younger, and Frederick Hawley,
both of Duffield, in the County of Derby, Paint and Colour Manufacturers, for
an Invention of "AN IMPROVED MILL OR APPARATUS FOR GRINDING PAINTS,
COLOURS, MINERALS, AND SIMILAR ARTICLES, AND ALSO FOR GRINDING
GRAIN"
PROVISIONAL SPECIFICATION left by the said William Hawley, the
younger, and Frederick Hawley at the Office of the Commissioners of
Patents on the 7th July 1881.
WILLIAM HAWLEY, the younger, and FREDERICK HAWLEY, both of Duffield, in
the County of Derby, Paint and Colour Manufacturers. "AN IMPROVED MILL
OR APPARATUS FOR GRINDING PAINTS, COLOURS, MINERALS, AND SIMILAR ARTICLES,
AND ALSO FOR GRINDING GRAIN."
The object of this Invention is to construct an improved mill or apparatus for
grinding paints, colours, minerals, and the like, either in a wet or dry state, with
greater rapidity and consequently at less cost than heretofore, and also for grinding
grain with greater rapidity.
In carrying our said Invention into practice, we construct an outer casing of
cast-iron or other suitable material of the requisite size and strength to carry the
stones. This case is formed with a feeding hopper on its upper end. Through
the centre of the case is fitted the vertical driving shaft which carries and rotates
the lower grinding stone (not the upper one as usual heretofore).
The lower end of this shaft is fitted with a vertical steel projecting plug or pin,
which rests and works in a recess formed in the head of a square steel cock, plug,
or nut; the shank of this cock, plug, or nut is fitted in the upper end of a vertical
screw, which works in a bracket attached to the underside of the said casing
directly under the said vertical shaft. The object of this simple arrangement is to
raise and lower the shaft and the rotating stone secured thereto to suit the work
required to be performed by turning a wheel attached to the lower end of the said
screw.

page_text: The lower or rotating stone is formed with its upper face inclined downwards
from near its upper central part to its outer edge at an angle of about 22° more or
less. The upper or fixed stone is nearly similarly bevilled on its underside, so as
to nearly fit the incline or slope of the said lower stone; but the bevil of the upper
stone is made at an angle of about 23°, or 1° more than the lower stone, thus
leaving a wider space between the two stones near the centre or feeding part, so as
to more freely admit the coarser material between the two stones to be ground.
In the eye of the upper stone is a "feed" fitted to the said shaft.
"
To the underside of the lower or rotating stone a "sweep is attached for
removing the ground material from the lower part of the case after having passed
from between the stones.
The raising and lowering parts can be taken out and replaced in a few minutes.
The mill may be made of any desired size, and also may be used as a pug-mill;
it may be fixed in any convenient place by any suitable and efficient means, and
can be worked either from the top or bottom of the shaft.
In our experiments with a pair of eighteen-inch French burr-stones, as above
described, we attained a speed of about six-hundred revolutions per minute.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Hawley, the younger, and Frederick Hawley in the Great
Seal Patent Office on the 4th January 1882.
WILLIAM HAWLEY, the younger, and FREDERICK HAWLEY, both of Duffield, in
"AN IMPROVED MILL OR
the County of Derby, Paint and Color Manufacturers.
APPARATUS FOR GRINDING PAINTS, COLORS, MINERALS, AND SIMILAR ARTICLES,
ALSO FOR GRINDING GRAIN."
The object of this Invention is to construct an improved mill or apparatus for
grinding paints, colors, minerals, and the like, either in a wet or dry state with
greater rapidity and consequently at less cost than heretofore, and also for grinding
grain with greater rapidity.
In order that our said Invention may be more fully understood and be more
readily performed, we will explain the same with the aid of the accompanying
Drawing which forms part of this Specification, reference being made thereto by
the numerals and letters marked thereon. The same index letters refer to similar
parts in each Figure of the said Drawing.
Fig. 1 is an elevation of our improved mill.
Fig. 2 is a vertical section of the same taken through the centre thereof.
In carrying our said Invention into practice, we construct an outer casing a of
cast-iron or other suitable material of the requisite size and strength to carry the
stones b, b. The said case a is provided with a feeding hopper c. Through the
centre of the case a is fitted the vertical driving shaft & which carries and rotates
the lower grinding stone b¹, and works in and is kept in place by the glands or
bearings d¹, d². The lower end of this shaft d is fitted with a vertical projecting
plug e, by preference of steel, which plug works in a recess formed as shown in
the upper part of a square or round steel cock, plug, or nut f; the shank or under part
of this cock, plug, or nut fis fitted on the upper end of a vertical screw g which
works in the bracket h. The object of this simple arrangement is to raise and
lower the shaft d and the rotating stone b¹ secured thereto at 62 to suit the work
intended to be performed; the said shaft and stone are moved up and down by
turning the hand-wheel 2, which is fitted to and operates the screw_g.
bearing d², the cock f, and the bracket h are fixed and kept in place by being
secured to and within a lower metal case j, which case j is efficiently bolted to the
upper case a, as shown at j¹.
The
The lower or rotating stone b' is formed with its upper face at k inclined down-
wards, as shown in Fig. 2, more or less as may be required. The upper or fixed
stone b is nearly similarly bevilled on its underside, say, about 1° more of bevil,
so as to nearly fit the incline of the lower stone b¹, thus leaving a wider space
between the two stones at the feeding part 1, so as to more freely admit the
coarser material between the two stones to be ground.
On the eye of the upper stone is a feed" fitted to the shaft d.
To the underside of the lower or rotatory stone b' a "sweep" m is fixed for
removing by the delivery spout n the ground material from the lower part of the
case after having passed from between the stones b, b'.
The raising and lowering apparatus, as shown, can be removed and replaced in a
few minutes.
For grinding wet material the top of the hopper c should be wider than the one
shown.
The mill may be made of any desired size, and also may be used as a pug-mill,
It may be fixed in any convenient place by any suitable and efficient means, and
even be suspended from a beam without any stand or case, and can be worked either
from the upper or lower part of the shaft.

page_text: In our experiments with a pair of eighteen-inch French burr-stones we attained
a speed of about 600 revolutions per minute.
After raising or lowering the shaft d it is held in position by the lock-nut o.
Having thus fully described and ascertained the nature of our said Invention
and the method of performing the same, we wish it to be understood that we do
not restrict ourselves to the precise forms, details, or dimensions, as now illustrated,
inasmuch as they admit of considerable variation without departing from the
principle of our Invention; for example, for large stones and shafts a large wheel
worked by a lever or by machinery may be required; also a bridge-tree may be
used for raising and lowering the shaft and rotating stone. But we claim as our
Invention and desire to secure by the before-mentioned in part recited Letters
Patent,
Firstly. Making the lower stone of a pair of grinding stones the rotating one.
Secondly. The shape of each grinding stone, especially the grinding surfaces
thereof, substantially as specified.
Thirdly. The method of raising and lowering the said rotating stone, substantially
as specified.
In witness whereof, we, the said William Hawley, the younger, and Frederick
Hawley, have hereunto set our hands and seals, this Thirtieth day of
December, in the year of our Lord One thousand eight hundred and
eighty-one.
WILLIAM HAWLEY, JUN. (L.S.)
FREDERICK HAWLEY.
(L.S.)