IMPROVEMENTS IN MILLS FOR GRINDING
Year: 1853

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's lun
Fields, in the County of Middlesex, and of Glasgow, North
Britain, Gentleman, for the Invention of "IMPROVEMENTS IN MILLS
FOR GRINDING."-A communication from Messieurs Fromont and
Machine Makers.
PROVISIONAL SPECIFICATION left by the said John Henry
Johnson at the Office of the Commissioners of Patents, with his
Petition, on the 22nd October 1853.
1, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, and of Glasgow, North Britain, Gentleman, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN MILLS
FOR GRINDING," being a communication from Messrs. Fromont and
Son, of Chartres, in the Empire of France, Machine Makers, to be as
follows:-
This Invention relates to the mode of driving the mill-stones, and to
the general arrangement of the various parts connected therewith. The
shaft which gives motion to the stone is driven by an intermediate shaft

page_text: fitted with a friction pulley and driven by contact only. This shaft
communicates its movement to the main shaft by a pinion and spur
wheel, the latter being keyed on to the main shaft. This shaft is made
hollow, and fitted with a funnel or expanded mouth-piece at its upper
extremity to receive the grain which falls on to a slightly dished plate
fixed within the funnel mouth a short distance below the mouth of
the feed pipe. By raising or lowering this pipe the feed is regulated
accordingly. The friction pulleys are pressed against the driving disc
by pressing springs, the contact being thus constantly kept up. By
withdrawing this pulley from the periphery of the main driving disc
the notion of the stone is stopped. The stones are supported by a
species of collar, being independent of the working stone. The grain
is-directed towards the periphery of the stones, the stones being driven
either from above or below by a very slight modification.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 22nd April 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of October, in the
year of our Lord One thousand eight hundred and fifty-three, in the
seventeenth year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said John Henry Johnson, Her special
license that I, the said John Henry Johnson, my executors, administra-
tors, and assigns, or such others as I, the said John Henry Johnson,
my executors, administrators, or 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,
usc, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Mait, an Invention

page_text: for "IMPROVEMENTS IN MILLS FOR GRINDING," a communication from
Messieurs Fromont and Son, of Chartres, in the Empire of France,
Machine Makers, upon the condition (amongst others) that I, the said
John Henry Jolinson, by an instrument in writing under my hand and
seal, 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 J, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is
to say :-
The said Invention relates to the mode of driving the mill-stones, and
to the general arrangement of the various parts connected therewith.
The shaft which gives motion to the stone is driven by an intermediate
shaft fitted with a friction pulley and driven by contact only. This
shaft communicates its movement to the main shaft by a pinion and
spur wheel, the latter being keyed on to the main shaft. This shaft is
made hollow, and fitted with a funnel or expanded mouth-piece at its
upper extremity to receive the grain which falls on to a slightly dished
plate fixed within the funnel mouth a short distance below the mouth of
the feed pipe. By raising or lowering this pipe the feed is regulated
accordingly. The friction pulleys are pressed against the driving disc
by pressing springs, the contact being thus constantly kept up. By
withdrawing this pulley from the periphery of the main driving disc the
motion of the stone is stopped. The stones are supported by a species
of collar, being independent of the working stone. The grain is
directed towards the periphery of the stones, the stones being driven
either from above or below by a very slight modification.
Figure 1, on the accompanying Sheet of Drawings represents a ver-
tical section of the actuating mechanism as applied to a mill stone from
above. but it may also be applied from below. Figure 2, is a plan of the

page_text: sanie. The mechanism consists of a mortice wheel A, keyed on to the
upper end of the vertical shaft B, which is made hollow or tubular, and
is fitted at its upper extremity with a cup C, in which is contained a
disc a, which receives the grain to be ground from the inclined pipe b.
This system replaces the ordinary fixed feeders, and the quantity of grain
which should pass into the mill is regulated by removing more or less
the lower or moveable portion of the pipe b, from the disc a. This is
effected by means of the lever d, fitted with a nut at one end, which
works on to the upper screwed end of the rod f, which is extended
downwards through the flooring for the purpose of affording facility for
regulating the supply from the floor of the mill-stones. The shaft B,
passes through a vertical cast-iron support D, which is fitted with
four brasses c, tightened up by means of tightening screws. This
support is cast in one piece with the bed plate E, which carries as many
repetitions of the above mechanism as there are mills, as shewn in the
general plan at Figure 3. The mortice wheel A, gears into the cast-
iron pinion F, fixed on to the shaft G, which carries the pulley H.
This pulley, which is of cast-iron, is covered with leather on its
periphery, the same as the pulley K, in Figures 3 and 4, thereby
enabling it to gear readily by a slight pressure. This pressure is
obtained by carrying the shaft G, in the moveable cast-iron support J,
which acts as a lever, the centre of motion of which is the shaft of the
inill-stone. The support J has a vertical collar-bearing cast upon it,
bored internally to fit over the support D, which is turned up externally.
It rests at its outer free end upon slides or planed grooves in the bed-
plate E, so that it may work freely round its fixed centre, at the same
time keeping the wheels A, and F, constantly in gear. A projection 1
also cast upon the bed-plate E, serves as a point of resistance for the
spring g, which presses against the free end of the moveable support or
standard J, and thereby keeps the pulley H in contact with the larger
one, which drives it at a high velocity. The pressure may be further
increased by means of the screw h, which passes through a nut fixed in
the metal of the projection L, and carries a hand-wheel i. This screw
serves also to stop the mill, as by simply turning it to draw back the
support J. the pulley H. will be disconnected from the large driving

page_text: pulley K, and consequently cease to rotate. As the vertical shaft G will
require to be well lubricated on account of the speed at which it rotates,
a peculiar lubricator is employed for lubricating the upper collar of the
shaft. A fixed pin k, is fitted into the support J, and answers as a
centre upon which the upper end of the shaft G, may turn. The lower.
end of this pin is hardened and fits into the brass collar-bearing 1,
The
which is fitted into the grease chamber in the top of the shaft.
oil by this means is kept in constant communication with the working
parts of the moveable brass and the fixed pin k, and is prevented from
escaping or wasting. This arrangement of driving mechanism is
evidently applicable also to mill-stones driven from below, the only
difference being that the position of the various parts will be changed
in relation to the mill-stones.
Another portion of the Invention is represented in vertical section at
Figure 5, and horizontal section at Figure 6. The collar-bearing or
support for the spindle of the upper stone is composed of a cast-iron
collar M, formed with a flange at its lower end to secure it to the
masonry N by rag-bolts, as shewn in the Drawing, or to cast-iron
columns of the requisite height. This support or collar is bored
smooth internally, and receives the vertical collar or hollow spindle O,
which in this case serves at the same time to carry the journal m. of
the shaft B' at the lower end, and the brass n at the upper extremity
in which the shaft B' rotates. If the mill-stones are driven from below
the cylindrical or hollow spindle O will be open at the bottom to allow
the spindle of the mill-stones to pass through. In order to close the
aperture formed in the lower mill-stone it is necessary to cover it with
a plate o, which rests upon the support M. It will thus be seen that
the support M is altogether independant of the under stone which is
enclosed and fixed in the iron casing P, by the screws p, and p. In
the arrangement shewn in the Drawings, that is, with the stones driven
from above, the end of the shaft B' carries a steel point 9, upon which
rests the cross-piece of the upper stone. The connection of the cross-
piece with the spindle of the mill-stone is effected by means of the
double clutch s, shewn in detail in Figures 7 and 8,-the lower portion
5 of which is fixed on to the top of the shaft B¹, and the other portion

page_text: forms part of the hollow shaft B. Two lateral inclined openings are
made at the junction of the shaft B, with the upper portion of the
clutch, thereby directing the grain which descends down the shaft B,
towards the circumference of the stones. Figures 3 and 4, represent
an elevation and plan the arrangement of a mill with six pairs of
grinding-stones, fitted respectively in a similar manner to that herein-
before <lescribed.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe, in conclusion, that I do not
confine or restrict myself to the precise details or arrangements which
I have had occasion to describe or refer to, as many variations may
be made therefrom without deviating from the principles or main features
of the said Invention; but what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in
part recited Letters Patent, is,-
First, the system or mode of driving mill-stones and accellerating the
speed by friction, as herein-before described.
Second, the application and use of the collar M, (Figure 5,) which is
independant of the fixed mill-stone, as herein-before described.
Third, the system or mode of connecting the driving spindle to the
cross-piece, (Figure 5,) of the running stone, and the arrangement
whereby the lower shaft or spindle rotates when the mill is driven from
above, as herein-before described.
Fourth, the system or mode of lubricating bearings, and the general
construction and arrangement of mills, as herein-before described.
In witness whereof, I, the said John Henry Johnson, have here-
unto set iny hand and seal, the Twenty-second day of April,
One thousand eight hundred and fifty-four.
J. HENRY JOHNSON. (L.S.)