AN IMPROVED METHOD OF AND MACHINERY FOR DRESSING MILLSTONES
Year: 1874

page_text: * LETTERS PATENT to George Haseltine, of the "International Patent
Office," Southampton Buildings, London, for the Invention of "AN
IMPROVED METHOD OF AND MACHINERY FOR DRESSING MILLSTONES."-A com-
munication from abroad by Seth Dean, William H. Smith, and
Henry Merrell, all of La Crosse, Wisconsin, United States of
America, Manufacturers.
COMPLETE SPECIFICATION filed by the said George Haseltine at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 9th June 1874, pursuant to the 9th Section of
the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HASELTINE, of the "International Patent Office," Southampton
Buildings, London, Doctor of Laws, send greeting.
WHEREAS I am in possession of an Invention for "AN IMPROVED
METHOD OF AND MACHINERY FOR DRESSING MILLSTONES," and have petitioned
Her Majesty to grant unto me, my executors, administrators, and

page_text: assigns, Her Royal Letters Patent for the same, and have made solemn
Declaration that it has been communicated to me from abroad by Seth
Dean, William H. Smith, and Henry Merrell, all of La Crosse, Wisconsin,
United States of America, Manufacturers.
NOW KNOW YE, that I, the said George Haseltine, do hereby declare
that the following Complete Specification, under my hand and seal, fully
describes and ascertains the nature of the said Invention, and in what
manner the same is to be performed, in and by the following state-
ment, reference being had to the accompanying Drawings forming a part
of this Specification :—
This Invention relates to an improved method of and apparatus for
dressing and furrowing millstones, and it consists in the employment of
a solid emery wheel revolving at a high speed to dress and furrow the
stones, and in a novel machine for driving and manipulating the cutter
wheel as herein-after described.
The object of the said Invention is to produce a machine by which the
millstones may have their furrows sharpened, and the glazing removed
from the face expeditiously and in such manner as to leave smooth
clean faces and sharp feather edges to the furrows.
It is a fact well known to all familiar with milling that the furrows
in the grinding stones have their edges worn rapidly away so that they
require to be frequently sharpened, and also that the oil contained in the
wheat forms a smooth hard glazing on the stones which interferes with
their proper operation and must be frequently removed. In dressing
the furrows it is very desirable that their inclined sides shall be as
smooth as possible, and that the opposite sides shall have sharp true
edges, and also that the flat or level faces shall be as smooth and true as
possible.
.
Various machines have been devised for the purposes of sharpening
the furrows and removing the glazing, but up to the present time they
have all failed to accomplish these purposes satisfactorily. Among
other plans that have been tried are those of using metal picks, revolving
metal cutters, and revolving cutters armed with diamond or carbon
points. By neither of these plans can the stones be prepared in such a
manner as to make the best quality of flour at once, for after the stones
are prepared their surfaces are so rough and irregular that it is necessary

page_text: to run from four to eight hundred bushels of grain through them before
they will produce the finest quality of flour.
.
Another very great objection to the diamond cutters, which are the
most in favor, is that they cannot be used to dress down the entire
surface, but merely for "cracking" as it is technically called. This
cracking" consists in breaking fine lines through, the surface so that
when the two stones are set running again the dust or particles loosened by
the "cracking" will take hold and remove the glaze from that portion of
the surface between the lines. At the same time however that the dust
and loose particles accomplish this purpose they wear away the sharp
edges of the furrows and thus in a measure defeat the end desired to be
attained.
After many experiments it has been ascertained that the true way
to dress and sharpen the stones is not by means of cutters acting
percussively thereon as heretofore, but by means of a smooth grinding
wheel acting thereon steadily and continuously with an abrasive action,
and that the only cutter which will answer the purpose is a solid wheel
or disc of emery revolving at a very high velocity. The employment
therefore of a rapidly revolving emery wheel for this purpose forms the
main feature of this Invention.
In practice it is found that the best results are attained by the use of
a wheel, about eight inches in diameter, driven at a speed of about
twenty-eight hundred revolutions per minute. A wheel thus driven and
applied with a moderate pressure will cut through the glazing and into
the body of the stone quite easily and with considerable rapidity, and
will leave the surface perfectly even and as smooth as the texture of the
stone will admit of. When the faces of the stones are to be dressed or
freed from glaze I use an emery wheel having a flat edge or face, but
when the furrows are to be dressed or sharpened I employ a wheel
having an edge of the exact size and form of the furrows, and then feed
it while revolving back and forth therein.
By means of the emery wheel I am enabled not only to remove the
glazing and sharpen the furrows with great rapidity, but to leave a
surface which permits the stones to be used at once for making the
finest quality of flour. Thus it will be seen I not only save expense and
labor in preparing the stones but also obviate the necessity of running
the coarse grain through, and save the time required therefor. As the

page_text: on the way or guide C, and has a hand wheel G applied to its outer end,
as shown in Figures 2 and 3, so that by turning the hand wheel the end
of way 0 may be moved inward and outward on arm B. On the way or
guide C I mount a sliding frame or carriage D, in whose lower end is a
transverse shaft h, on the end of which the emery cutting wheel J is
secured, as shown in Figures 1 and 2. Along the side of the way C
I mount a screw shaft H which passes through a nut on the carriage D
in order to move the latter back and forth on the way C, so as to carry
the cutting wheel to and from the edge of the stone. On the arm B
I secure two standards i and mount therein a horizontal shaft B¹
provided with a sliding pulley K, and also with a bevel pinion U, which
gears into a pinion S mounted on the upper end of the centre post A, as
shewn in Figures 2, 3, and 6. The pulley K is prevented from turning
on its shaft by a spline thereon, and it is provided on one side with a
grooved hub into which there fits an arm d secured to the way or
guide C. When the way C is moved sidewise on the arm B the arm d
moves the pulley to correspond and thereby keeps it always in line with
the other pulleys on the way C, as herein-after explained.
On the shaft of the cutter wheel J I secure a pulley I, and in the
upper corners of the moveable frame D which supports the shafts I
mount two pulleys a, as shewn in Figure 1. I mount a pulley L on the
outer end of the way C and pass a driving belt A' around the pulleys K
and L, over the pulleys a, and under the pulleys 7, on the shaft of the
cutter wheel, as shown in Figure 1, so that when the belt is set in
motion it drives the cutter wheel J and the pulley L. The peculiar
arrangement of the belt and the pulleys a permits the carriage D to
move back and forth on the way without affecting materially the tension
of the belt or its action on the cutting wheels. The screw H which
moves the carriage or frame D and the cutter wheel is provided on its
outer end with a pulley Q which is driven by a belt P from a pulley O.
just above, as shown in Figures 1 and 2. The shaft which carries the
pulley O is provided with two bevel pinions M and N, and is connected
by a swivel with an upright hand lever Z by moving which the
shaft can be adjusted endwise. On the side of pulley L there is a
pinion D¹ which gears with one or the other of the pinions M, N,
according to the direction in which the hand lever is moved. When the.
lever is moved in one direction the pinion M is thrown in gear and the
screw
set in motion so as to feed the frame D and its cutting wheel

page_text: in one direction, while if the lever is moved in the opposite direction the
pinion N is thrown in gear and the lateral movement of the frame
and cutter reversed. Thus it will be seen that by simply moving the
lever Z to and fro the cutter is caused to travel back and forth, to and
from the edge of the stone, while at the same time it revolves at a high
speed.
The shaft of the cutter wheel J is not mounted rigidly in the frame D
but in a vertical slide o attached to the frame and held by a hand
screw I, as shown in Figure 1. By adjusting the said screw the cutter
may be raised and lowered as may be required. The pulleys a are also
mounted on the slide o so that they remain in the same relative position
to the pulley of the cutter wheel, notwithstanding its adjustment up
and down. The way C, on which the carriage or frame D slides, is
provided with a brace d which has a screw C¹ bearing on a block or
shoe K', as shewn in Figure 1. This brace and shoe form the support
for the outer end of the way or guide c. The way is ordinarily arranged
parallel with the face of the stone, but by turning down the screw C¹ its
outer end may be raised, so that as the cutter wheel moves outward
toward the edge of the stone it will be gradually raised. In this way
the furrows may be made of decreasing depth toward the edges of the
stone.
In employing this machine on the lower or bed stone I place the
central post A. over the mill spindle and bolt it down firmly in place, as
shewn in Figures 2 and 6. I then pass a shaft X down through the
post A and pinion S and connect it to the mill spindle and to the pinion
by suitable couplings, as shown. When the spindle is set in motion it
drives the shaft which in turn drives the pinion S and sets the machine
in operation.
When the said machine is to be used on the upper or runner stone
the stone is placed face up by the side of the bed stone in the usual
manner, as shown in Figure 3. The centre post is then bolted down
on the stone, and the pinion S provided with a shaft T carrying a
pulley V. The shaft ✗ is then coupled to the mill spindle and provided
with a pulley W, and lastly, the pulleys V and W are connected by a
belt y. By this arrangement motion is communicated from the mill ;
spindle to the machine on the upper stone located at one side.
When the said machine is in motion the cutter wheel is carried along.
the side of the way C automatically. By adjusting the screw I the

page_text: cutter may be raised and lowered as desired, and by swinging the arm B
and adjusting the screw the cutter may be caused to travel over every
portion of the surface and in any desired direction.
Having thus fully described the said Invention, as communicated to
me by my foreign correspondents, and the manner of performing the
same, I wish it understood that I claim,―
First. The herein-described method of dressing and furrowing mill-
stones, that is to say, by means of a rapidly revolving wheel of emery.
Second. The central tubular post provided with the pinion S in com-
bination with the frame of the machine pivoted thereon, and provided
with the pinion U and screw R or equivalent contrivance as described,
whereby the machine may be driven by the mill spindle.
Third. The adjustable shoe or equivalent device arranged to support
the outer end of the way C, whereby the way may be inclined and the
cutter caused to rise as it approaches the edge of the stone, as hercin
set forth and for the purpose specified.
Fourth. The support or equivalent device provided with a shaft
arranged to be connected to the mill spindle whereby the machine when
placed on the upper stone may be operated directly from the mill
spindle, as herein set forth.
In witness whereof, I, the said George Haseltine, have hereunto
set my hand and scal, this Ninth day of June, in the year of
our Lord One thousand eight hundred and seventy-four.
25 Witness,
H. J. NOONE,
8, Southampton Buildings,
London.
GEORGE HASELTINE. (L.S.)