IMPROVEMENTS IN MILLS FOR GRINDING GRAIN
Year: 1862

page_text: LETTERS PATENT to John Turnbull, of Barnard Castle, in the County of
Durham, Brass and Iron Founder, for the Invention of "IMPROVEMENTS
IN MILLS FOR GRINDING GRAIN."
PROVISIONAL SPECIFICATION left by the said John Turnbull at the
Office of the Commissioners of Patents, with his Petition, on tho
23rd October 1862.
I; JOHN TURNBULL, of Barnard Castle, in the County. of Durham, Brass
and Iron Founder, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MILLS FOR GRINDING GRAIN," to be as follows:-
My Invention relates to that class of mills for grinding grain, known as
vertical mills, that is to say, the bed or stationary stone is placed on its edge
and the grinding surface therefore in a vertical position, while the running
stone is mounted on a horizontal axis, its face being brought up parallel to
the face of the bed stone. I place the bed stone to about half its thickness
in a cast-iron box or case, which encircles and fits it somewhat closely; bolts
fixed with lead in the stone will project through holes in the disc of the case,
over which are mounted bridge pieces fixed on the case; the screw parts of the
bolts pass through these bridge pieces and are held by nuts on each side of
such bridge pieces, by which means the position of the bed stone can be
adjusted. The shaft on which I mount my running stone passes quite through
the bed 'stone, and is supported at that end by a bearing formed in a cast-iron
boss fitted on: the eye of the stone, or the shaft may pass freely through the
end of such boss and be supported by an independent bearing. The boss

page_text: fitted in the eye of the bed stone is cylindrical, and considerably larger than
the shaft which occupies the centre, in order to receive an archimedean screw,
which carries the feed through the bed stone and up to the face of the running
This screw is fixed on the shaft and therefore rotates with it. The
feed is delivered by a spout into a small hopper or shoot made on the back
end of the boss which conducts it to that end of the screw. The cylindrical
boss is bolted to the case receiving the bed stone. The hopper receiving the
grain in bulk is in suitable position, and has a regulating slide to limit the
passage of the grain which passes from thence by a spout to the boss hopper
before mentioned; this shoot I fit with what I term a spring bottom,
being a sheet of metal by which the upper end is attached, towards the other
end it is suspended by a rod furnished with a regulating screw and nut.
Immediately below the shoot bottom I mount a tappet piece on the end of
the stone shaft, which projects through the stone boss, as before mentioned;
the tappet has two, three, or more points of. contact, which strike the bottom
of the shoot and cause the grain to pass regularly down the shoot, whereby a
regular supply of the grain to the stone is insured. In order to regulate the
feed, and cause it to supply more or less, I raise or lower the shoot by the
regulating screw before mentioned, and so cause the tappets to strike the bottom
with greater or less force. The stones are enclosed in a casing, and air vents
provided as usual. The bearing on which the end of the shaft rests next the
running stone is fitted with a sliding brass, against which a screw takes,
whereby it and consequently the shaft and running stone can be fixed and kept
up to the bed stone at a regulated distance. The journal of the shaft I can
furnish with one or more projecting rings which fit into grooves in the brass,
the end of which further has a raised part bearing against the end of the
shaft; these together take the thrust of the screw and transmit it to the shaft.
The standards of the shaft bearings, and also the frame of the bed stone are
mounted on a suitable foundation or flooring to keep them in proper relative
positions, as well understood. .
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Turnbull in the Great Seal Patent Office on the 22nd
April 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
TURNBULL, of Barnard Castle, in the County of Durham, Brass and Iron
Founder, send greeting.

page_text: WHEREAS Her most. Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of October, in the year of our
Lord One thousand eight hundred and sixty-two, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs. and successors, give and grant unto me;
the said John Turnbull, Her special licence that I, the said John Turnbull;
my executors, administrators, and assigns, or such others as I, the said John
Turnbull, my executors, administrators, 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 "IMPROVEMENTS IN MILLS
FOR GRINDING GRAIN," upon the condition (amongst others) that I, the said
John Turnbull, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, 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 I, the said John Turnbull; do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):
.
My Invention relates to that class of mills for grinding grain known as
vertical mills, that is to say, the bed' or stationary stone is placed on its
edge, and the grinding surface therefore in a vertical position, while the
running stone is mounted on a horizontal axis, its face being brought
up parallel to the face of the bed stone. I place the bed stone to about
half its thickness into a cast iron box or case which encircles and fits it
somewhat closely, and bolts fixed with lead in the stone project through
the holes in the disc of the case, over which are mounted bridge pieces fixed
on the case; the screw parts of the bolts pass freely through these bridge pieces.
and are held by nuts on each side of such bridge. frames, by which means the
position of the bed stone can be adjusted at will. The shaft on which I mount'
my running stone passes quite through the 'bed stone, and is supported at
that end by a bearing formed in a cast-iron boss, fitted in the eye of the 'stone,
or the shaft may pass freely through the end of such boss, and be supported
by an independent bearing. The boss fitted in the eye of the bed stone is
cylindrical, and considerably larger than the shaft which occupies the centre,,

page_text: :
upper
end
in order to receive an archimedian screw which carries the feed through the
bed stone, and up to the face of the running stone. The screw is fixed on the
shaft, and therefore rotates with it. The feed is delivered by a spout into a
small hopper or shoot made on the back end of the boss which conducts it to
that end of the screw. The cylindrical boss, is bolted to the case réceiving
the bed stone. The hopper receiving the grain: in bulk is in suitable position:
and has a slide to regulate the passage of the grain, which passes from thence
by a spout or shoot to the boss hopper before-mentioned;, this shoot I fit with
what I term a spring bottom, being a sheet of metal by which the'.
is attached, it is suspended towards the other end by a rod furnished with
a regulating screw and nut. Immediately below the shoot bottom I
mount a tappet piece on the stone shaft which projects through the stone.
boss as before-mentioned. 'The tappet has two, three, or more points of
contact which strike the bottom of the shoot and cause the grain to: pass
regularly down the shoot, whereby a regular supply of grain to. the stone is.
insured. In order to regulate the feed, and cause it to supply more 'ortless,
I raise or lower the regulating screw before-mentioned, and so cause the
tappets to strike the bottom with greater or less force.
enclosed in a casing and air vents provided as usual. The bearing on
which the end of the shaft rests next the running stone is fitted with a sliding
brass, against which a screw takes, whereby it, and consequently the shaft and
running stone, can be forced and kept up to the bed stone at a regulated:
distance. This journal of the shaft I'furnish with one or more projecting.
rings, fitting into grooves in the brass, the end of which further has a raised
part bearing against the end of the shaft, these together take the thrust of
the screw; the standards of the shaft bearings; and also the frame of the bed
stone are mounted on a suitable foundation or flooring to keep them in proper.
The stones are:

page_text: parts of the bolts F, I apply two nuts, one on each side of the bridge piece,
by which the stone can be drawn into position adjusted and firmly fixed in
the case D. H is a hollow cast-iron boss fitted in the eye of the bed stone,
and fixed therein by a flange bolted to the case D. The boss H is bored out
or otherwise prepared to receive a screw I, fixed on shaft K, which carries the
running stone L, this shaft is fitted in bearings carried by standards M, M;
from the base C. The running stone L is fixed to the shaft K as usual, and
is held up to the bed stone by a screw N, fitted on the boss of bridge
piece O. The screw abuts against a raised part of the brass bearing between
the screw and the shaft K, the bearing being free to slide, moves towards the
bed stone when forced up by the screw. To permit of the sliding motion of
the shaft K it is fitted without, collars in the bearing at its opposite end.
The boss H is furnished with a hopper R, which, receives the feed to be
ground; conducting it to the screw I, which by its rotation carries the grain
through the eye of the bed stone towards the running stone. S is the hopper
into which the grain is deposited; from this hopper it passes by a shoot T,
which has a spring bottom, being a sheet of steel which forms the bottom, and
extended so as to unite the bottom of the shoot T with the bottom of hopper S.
The lower end of the shoot Trests on a small hopper or receiver R, but
which is lifted and allowed to drop thereon by a tappet piece U fixed on the
shaft K, this may have one, two, three, or more points of contact as may
be desirable; the tappet piece U strikes the piece V fixed on the bottom
of the shoot, throwing it upwards and allowing it to fall as before described,
by which means the grain to be ground is caused to flow with great regularity
from the hopper S to hopper R, and thence to the grinding surfaces, which
being fed with the amount of grain which they are capable of grinding
properly and effectually, the result produced is satisfactory, both as regards
the amount and quality of the work performed. The end of the shoot resting
and falling on the hopper would produce the greatest amount of feed, but in
order to regulate and reduce it, I suspend the hopper by a screwed rod W,
which is supported by a nut X resting on bracket Y. By raising the lower
end of the spout by means of the nut and screw W, X, the spout will be
raised from hopper R, and will not be struck so hard or thrown up so high as
before, in this way it may be regulated so that the spout receives very slight
blows from the tappet piece, whereby the feed may be reduced to a minimum.
The feed from hopper S is regulated in the first instance so that it will not
overflow the shoot, but merely permit to pass the quantity to pass that may be
required for the full feed shoot T, by the action of which the feed to the stones
is regulated to great nicety. The screw should be made of such a rake and

page_text: pitch as will carry up. the greatest amount of grain to the stones that they
are capable of grinding. Z is a sheet-iron casing to enclose the stones and
receive the flour, which falls into the hopper or receiver at bottom and passes
thence by a spout Z', into racks or any suitable receptacles..
Having described the nature of my Invention, and the manner of per-
forming the same, I declare that what I claim as my. Invention to be
protected by the herein-before in part recited Letters Patent, is,-
First, the application of a screw I to vertical grinding mills in the manner
and for the purposes herein-before described. .
Secondly, the mounting and fitting the feed hopper or shoot T, and parts
connected therewith, of vertical grinding mills for the purpose and to act in
the manner herein-before described.
In witness whereof, I, the said John Turnbull, have hereunto set my
hand and seal, this Twentieth day of April; in the year of our Lord
One thousand eight hundred and sixty-three.
TOTAL MEID
JOHN TURNBULL. (L.B.)