An Improved Vertical Stone Grinding Mill.
Year: 1889

page_text: Date of Application, 18th Oct., 1889
Complete Specification Left, 23rd May, 1890-Accepted, 28th June, 1890
PROVISIONAL SPECIFICATION.
An Improved Vertical Stone Grinding Mill.
I ROBERT GRAHAM of Blackfriars Street in the City of Carlisle in the County of
Cumberland Millwright, do hereby declare the nature of my invention for AN
IMPROVED VERTICAL STONE GRINDING MILL to be as follows:-
Two stones hooped with iron placed in a vertical position the one running the other
fixed. The fixed stone has a cast iron face plate bolted to it. The stone hangs loose
on a projecting arm or boss which arm is bolted to frame. To prevent stone revolving
it is held by two screws projecting from each end of the frame into the outer
diameter of stone. The revolving stone has a cast iron face plate bolted to it; which
plate is keyed to a shaft communicating, through both stones and through projecting
arm attached to fixed stone,-with pedestals on frame. To shaft is attached a worm
passing through fixed stone as far as its inner face to convey ingredients from hopper.
The two stones are mounted on a cast iron frame with projecting brackets for
pedestals.
Dated this 17th
1000
Dated this 17th
day of October 1889.
1000
ROBERT GRAHAM.
COMPLETE SPECIFICATION.
An Improved Vertical Stone Grinding Mill.
I ROBERT GRAHAM, of Blackfriars Street, in the City of Carlisle, in the County of
Cumberland, Millwright, do hereby declare the nature of my invention to be particularly
described and ascertained in and by the following statement
My Invention relates to improvements in small grist mills, such as are suitable for
the wants of farmers who may desire to grind corn from time to time as desired.
In order that my invention may be the better understood I now proceed to describe
the same in relation to the drawings hereunto annexed, reference being had to
the letters and figures marked thereon. Like letters refer to like parts in the various
figures.
Figure 1. is a longitudinal section through the axis of rotation of my improved
grist mill.
Figure 2. is an outside elevation of the same.
My mill consists of two stones A and B placed vertically, the one A revolving in a
vertical plane with the driving shaft C, the other B hangs upon an extended arm M
attached to the bearing bracket E, and remains stationary. The stones are contained
within a casing F to which is attached a hopper G.
The corn to be ground is placed in the said hopper G and by a suitable inclination
of the bottom of the hopper issues gradually through an orifice d provided with an
adjustable slide into a shaking shoe H.
This shaking shoe is given a vibratory motion by the lever h pivotted on the frame
mouth, and reciprocated by a grooved cam wheel K on the rotary axis.
The corn is thus delivered from the shaking shoe into the frame mouth L, passing
thence into the interior of the extended bracket arm M which is provided with a
worm N and sleeve fitted over and rotating with the driving spindle C. the corn is
thus fed to the middle face of the two stones.
The revolving stone A is fitted to a metal disc and boss a by bolts leaded into the
stone, the said boss a being keyed to the driving spindle suitable ribs a¹ being
provided on the face of the metal disc & recessed into the back of the stone to form
a resistance against turning of the stone on its disc.
The fixed stone B is provided with a metal face plate having ribs b' recessed in the

page_text: back of the stone, and bush b forming a chamber projecting into the centre of the
stone for such a distance as to allow for the wearing down of the stone, bolted to
the stone by leaded bolts, and which fits over and rests upon the extended arm of the
bracket M, and is thus held in a truly vertical plane parallel to the grinding surface
of the revolving stone A.
The said stone B is prevented from revolving by two screws D projecting from the
frame or case into the outer periphery of the stone.
These stones inay be conveniently hooped with iron. One end of the revolving
spindle Crests in a bearing provided in the bracket E and the other end in a similar
bearing P both supported on a frame Q.
The thrust of the revolving stone A upon the fixed stone B is carried by a flange n
of the worm N pressing against the face of the adjacent bearing so that the grinding
faces of the stones are prevented from coming into actual contact.
At one end of the driving spindle C is a loose piece of case hardened steel against
which presses a screwed rod upon which are fitted a hand wheel R fixed thereto
and a locking lever S the screw passing through a screwed collar of the bearing P.
so that the relative distance of the two stones can be accurately adjusted and locked,
and the revolving stone A can be pressed up to its work.
The other end of the driving spindle is intended for the pulley for the driving
belt.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is
1st. In a vertical stone grist mill the combination with the fixed stone of a cast
iron plate with bosses and ribs let into the back of and bolted to the said stone and
with a central chamber projecting into the stone, only so far as to allow for the
wearing down of the grinding surface of the stone substantially as described.
2nd. In a vertical stone grist mill the extension of a bearing bracket through the
centre of such chamber in the cast iron plate so attached as aforesaid to one of the
stones to form a stationary fixed support therefor, keeping the said stone in a vertical
plane parallel to the grinding surface of the revolving stone, substantially as
described.
3rd. The formation of a chamber within the said extended bracket arm in com-
munication with the external hopper mouth, through which the material to be ground
is conveyed by a revolving worm, fixed to the central driving spindle, to the grinding
surfaces of the two stones, substantially as described.
4th. The adaptation of a worm sleeve provided with a collar resting against a
bearing to prevent the grinding faces of the two stones being brought into contact
substantially as described.
Datod this 2nd day of Max 1800
FELL & WILDING,
1, Queen Victoria Street, E.C., Agents for the Applicant.