AN IMPROVED MODE OF VENTILATING MILLSTONES
Year: 1865

page_text: LETTERS PATENT to Henry Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Mechanical Draughtsman,
for the Invention of "AN IMPROVED MODE OF VENTILATING MILLSTONES."
A communication from abroad by Alexandre Désiré Lagoguey, of
Boulevard Beaumarchais, Paris, in the Empire of France.
Sealed the 17th April 1866, and dated the 18th November 1865.
PROVISIONAL SPECIFICATION left by the said Henry Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on
the 18th November 1865.
I, HENRY EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane,
in the County of Middlesex, Mechanical Draughtsman, do hereby declare
the nature of the said Invention for "AN IMPROVED MODE OF VENTILATING
MILLSTONES," to be as follows:-
The friction which results from the action of the millstone on the grain
produces a rise of temperature which is injurious to the flour, which thereby
loses a portion of its gluten. The dry gluten produces a deposit that sticks
in the grooves of the stones, and necessitates the frequent washing of the
stones. The waste thus produced is a great loss, not so much from the
weight of the material that is thrown away as from the time and manual
labour lost in the cleaning. In fact this overheating prevents the stones from
working above a certain velocity; this limits the quantity of grain that can be
ground by a pair of millstones, a quantity that can be sensibly increased when

page_text: the overheating does not take place. It has hitherto been thought sufficient
to place in the rotary millstone, or in the eye, holes or oblique tubes for the
purpose of introducing fresh air by suction; but at the end of a certain time
these holes and tubes become stopped up by the flour. The object of this
Invention is to drive in air through the eye, and force it between the grinding
surfaces, and thus keep them cool.
The apparatus consists of a ventilator or other suitable blast apparatus,
which forces air through a tube adapted to the eye of the upper millstone,
and thus assures the certain and complete supply of the air between the mill-
stones. The quantity of air can be regulated by means of a valve, which
permits the necessary quantity to pass to ensure a good working. In this
manner the quantity of air may be varied according to the velocity that is
given to the millstones, and the different sorts of grain which are operated
upon.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Edward Newton in the Great Seal Patent Office on
the 12th May 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Mechanical Draughtsman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of November, in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Henry Edward Newton, Her special licence that I;
the said Henry Edward Newton, my executors, administrators, and assigns,
or such others as I, the said Henry Edward Newton, my executors, ad-
niinistrators, 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 "AN IMPROVED MODE OF VENTILATING MILLSTONES,"
being a communication to me from abroad, upon the condition (amongst
others) that I, the said Henry Edward Newton, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature

page_text: 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 I, the said Henry Edward Newton, 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 Drawing hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
Numerous attempts have been made from time to time for many years past
to cool meal or flour during the operation of grinding grain. It is well known
that the friction resulting from the action of the stones on the grain produces
a considerable elevation of temperature which injuriously affects the meal or
flour. First, the heated flour loses a portion of its gluten, as has been
ascertained by direct experiment made on the flour before and after the
passage of the grain between the stones. Second, the injured gluten pro-
duces a sticky deposit that fixes itself in the grooves of the millstones and
obstructs them, so that it is necessary to wash the stones frequently. This
occasions a great loss of time and expense, arising as much from manual
labour required to clean the stones as from the time that the stones are
standing idle. Moreover when this overheating takes place not more than
one-third the quantity of grain can be ground as when the millstones are in
good working order. It results from this that the grain ground by pressure
unquestionably spoils the flour by the action of the caloric, without, however,
being able to arrive at a good result or yield of flour. By avoiding this over-
heating of the flour a great economy in the manufacture will be effected, for
with the same amount of material a gain of about two per cent. of flour will.
be obtained without counting a saving of half per cent., which would result
from evaporation.
It is well known that at the present time a pair of stones requires dressing
every six days, and this dressing costs on an average six francs. By the
improved system it will only be necessary to dress the stones every nine days,
and the action of the heat which produces the sticky deposit in the grooves
will be totally avoided. From this it will be evident that instead of dressing
the stones sixty times a year, it will only be necessary to do so forty times,
thus producing a saving of twenty times six francs, or one hundred and
twenty francs per annum, on the dressing of each pair of stones. In the
second place this difference will give an addition of twenty working days to
every pair of stones throughout the year, and this will give a very great

page_text: advantage. It has hitherto been thought sufficient to place in the: moving
stone holes or oblique tubes, for the purpose of introducing the fresh .air
through the action of aspiration, but at the end of a certain time these holes
and tubes become choked up by the flour, and then the renewal of the air
does not take place, as the increase of temperature heats the air in the mill-
stone tubes above the temperature of the external air, and causes it to rise in
the tubes in consequence of its greater lightness. This will cause the draught
to operate in the opposite direction to that in which it ought to pass in order
to effect the cooling of the stones.
The means which the Inventor of the present process adopts for obviating
these difficulties consists in the employment of a ventilator, fan,. or other
blowing apparatus, the action of which ensures the complete renovation of the
air on the stones, and furthermore the quantity of air which it is desired to
supply may be regulated by means of valves, which will admit of only
introducing the quantity necessary for the proper working of the apparatus.
By this means the volume of air may be varied according to the quantity of
grain which it is required to supply to the stones, and the different kinds of
grain to be operated upon.
In the accompanying Drawings Fig. 1 is a vertical section of a pair of
millstones to which the improved system of ventilation or aeration is adapted,
and Fig. 2 represents a horizontal section of the same.
The apparatus consists of a ventilator or other suitable blast apparatus,
which forces the air from V through a tube T which surrounds the grain
supply pipe S into a space between two moveable metal cones M, N. These
two cones are held in position by a support L, one end of which is pivotted to
a bracket Q, whilst the other end is furnished with an adjusting screw P,
which allows the height of the cones M, N, to be regulated with accuracy.
The eye of the rotary millstone B carries a sort of metal groove, tube, or
trench F, furnished at its lower end with four bent tubes, intended to convey
the air coming from the ventilator at V between the stationary millstone A
and the rotary millstone B. These four tubes are united together at. their
lower end by another groove or trench G, which distributes the air on all the
face of the millstone. This millstone is cut away in four places, in. such a
manner as to facilitate the introduction of the air, as seen at O, Figs. 1
and 2. Between each of these cut-away parts the level surface of the stone.
is left, and serves to take and operate on the grain which falls from the
funnel K. It will be seen in Fig. 1 that the groove or trench F moves with
the rotating stone on which it is fixed, and it is therefore necessary that it
should be adjusted with great precision on the cone M, N. The screw P

page_text: permits the two cones to be adjusted exactly in contact with the groove or
trench F. The groove or trench G is placed from half an inch to an inch
above the lower level of the stone B, in order that this latter may be used
without being obliged to alter the height of the blowing apparatus. A hollow
glass sphere H is used, in order that the miller may see the grain fall into the
funuel K which conducts it to the millstones. The portion of the central
tube S corresponding to this sphere is also made of glass. In consequence of
the arrangement of parts above described the fresh air on entering from the
ventilator at V does not find any escape but between the millstones, and con-
sequently the temperature is kept down. The current of air generally caused
by the moving of the millstones also has a favorable effect. The supply of
the air between the millstones being under pressure, the air can never pass
in the wrong direction, the cooling of the stones is therefore ensured. The
quantity of air supplied to the stones is regulated by a valve J fixed in the
entrance of the air pipe T, and the movement of this valve is regulated or
governed by a small handle which moves on a dial, and thus indicates the
position of the valve in the pipe T.
Having now described the nature of the said Invention, and having
explained the manner of carrying the same into effect, as communicated to
me by my foreign correspondent, I wish it to be understood that under the
above in part recited Letters Patent I claim, the mode herein described for
ventilating millstones.
In witness whereof, I, the said Henry Edward Newton, have hereunto
set my hand and seal, the Eleventh day of May, in the year of our
Lord One thousand eight hundred and sixty-six.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
H. E. NEWTON. (L.B.)