IMPROVEMENTS IN MILLS
Year: 1858

page_text: PROVISIONAL SPECIFICATION left by Réne Prosper Lavie at the Office
of the Commissioners of Patents, with his Petition, on the 4th September
1858.
I, RENE PROSPER LAVIE, of the City of Paris, in the Kingdom of France,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
MILLS," to be as follows:-
This Invention consists of the following improvements :-
Firstly, in the particular means employed for regulating and maintaining
the running stone upon its pivot.
Secondly, in the arrangement and use of the rhynd of the stone spindle as
a breaker.
Thirdly, in the arrangement of certain parts of the rhynd and its cover;
which are furnished with an upper and lower stone of small size, forming the
breaker.
Fourthly, the use of a cylinder for supplying the corn to the breaker.
Fifthly, the use of a conical helical sifter for separating the "middlings."
Sixthly, the use of stones, either small or large, placed one upon the other.
horizontally, and directly or indirectly worked.
In mills with small horizontal stones, the running stone, owing to its light-
ness,. does not usually exert a sufficient pressure on the corn, and is liable to.
ta
rise. To remedy this defect, it is necessary to obtain a greater pressure on the
pivot of the said stone without interfering with its freedom of motion, and
which is effected in the following manner:

page_text: At the upper end of the stone spindle a rhynd is fixed by means of screws
or otherwise, the same having a lateral aperture traversed by a cross piece
which rests upon a pivot, and has upon its upper surface a spherical pro-
tuberance, against which the end of a screw passing through the cover
of the rhynd presses.
The last-mentioned. cover is furnished with helical wing-like appendages,
serving to sift a portion of the flour, as herein-after described, and intended
likewise to counteract by their attraction the effects of the centrifugal force,
which in mills with small stones, where the velocity is necessarily very great,
causes the grain to accumulate too much near the eye of the running stone.
The cover, which is fixed upon the rhynd; is fitted to receive the two small
upper and lower stones, or it may also be used as a metal grinder. The
stones or grinders are grooved or radiated as well as the duct herein-after
mentioned, in order to break the corn without cutting it, as done by the
breakers now in use. If desired, brushes may be adapted to the wing-like
appendages of the before-mentioned cover, which brushes sweep the flour
ground by the small stones, before mentioned, through a wire cloth cylinder
provided for that purpose, in order to prevent certain portions of the broken
corn from falling between the large stones and being further ground. By
these means a useful kind of "middlings" is obtained.
The upper part of the breaker consists of a duct or conduit, at the bottom
of which is the second stone or a metal grinder. The said duct is circular,
and remains fixed when the stones are set for grinding. It is held in its place
by means of a cross piece, the centre of which is traversed by a socket. To
the right of the centre of the cross piece is a bearing in which a lever is fixed
by means of a bolt, and which lever regulates the distance between the stones.
On the cross piece, and to the left of its centre, is a bearing, in. which is
immbedded a set screw, moved by means of a small fly wheel. The said screw
works in a nut formed on the end of the said lever, and furnished with two
studs fitting into apertures in the end of the lever. The lever is traversed by
the said duct by means of suitable openings, a bolt also being passed in an
opposite direction through the lever and the duct, which latter can by this
ineans be raised or depressed according to the motion communicated to the
lever by the said fly wheel and set screw. The upper portion of the said duct
is traversed by a spindle, by ineans of which a cylinder is introduced into the
said duct. The said cylinder has three openings in its diameter, and serves as
a feeder from the hopper to the stones of the breaker. The rotation of the
spindle brings these openings successively before a small door through which the
grain falls into the cylinder, and thence into the breaker. On the other end-

page_text: of the spindle is a grooved cone, which rests on a suitable bearing fixed to the
adjacent uprights and to the cross piece. The stone spindle is held in its step
by means of a spiral spring, one end of which presses against a drum attached
to the said spindle, the other end of such spring resting on a bush fixed on the
stone spindle by means of thumbscrews.
The following advantages are gained by the above system :-
Firstly, the stone spindle cannot rise out of its bed, while motion can be
freely imparted to it by means of a fly wheel suitably arranged.
Secondly, the large running stone cannot rise after it has once been set,
while its oscillatory motion remains free.
Thirdly, that all the flour from the breaker need not pass under the great
stones unless desired.
Fourthly, that the large running stone is partly held in place by the resist-
ance of the grain in being crushed.
It may be observed that, if considered desirable, the stone spindle may be
made in one piece, that is, without a rhynd.