IMPROVEMENTS IN GRINDING MILLS
Year: 1878

page_text: LETTERS PATENT to John Pickering, of Cubitt Town, Poplar, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN GRINDING MILLS."
PROVISIONAL SPECIFICATION left by the said John Pickering at the Office
of the Commissioners of Patents on the 16th February 1878.
" IM-
JOHN PICKERING, of Cubitt Town, Poplar, in the County of Middlesex,
PROVEMENTS IN GRINDING MILLS."
My Invention has for its object improvements in grinding mills.
In my improved mill the seed or other granular substance to be reduced is
crushed or ground between rotary bevilled or conical annular grinding faces,
suitably mounted in pairs on shafts, whose distance apart is adjustable. The shafts
are parallel to each other, and the bevilled or conical annular grinding faces are
arranged in sets of four; two fixed back to back on suitable arms or bodies on one
shaft work between two other similar grinding faces arranged facing each other a
short distance apart on suitable arms or bodies upon another shaft.
The seed or other substance fed between these grinding faces by a suitable
hopper or feeder. Two or more such sets of grinding faces as above described may
be used in one mill.
The annular bevilled or conical grinding faces are adjustable and readily re-
movable, and when worn can be easily renewed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Pickering in the Great Seal Patent Office on the 16th August
1878.
JOHN PICKERING, of Cubitt Town, Poplar, in the County of Middlesex. "Iм-
PROVEMENTS IN GRINDING MILLS."
My Invention has for its object improvements in grinding mills.
In my improved mill the seed or other substance to be reduced is crushed or
ground between rotatory bevilled or conical annular grinding faces suitably mounted
in pairs on shafts, whose distance apart is adjustable. The shafts are parallel to
each other, and the bevilled or conical annular grinding faces are arranged in sets
of four; two fixed back to back on one shaft work between two other similar
grinding faces arranged facing each other a short distance apart on another shaft.
The seed or other substance is fed between these grinding faces by a suitable
hopper or feeder. Two or more such sets of grinding faces as above described may
be used in one mill.
The annular bevilled or conical grinding faces are adjustable and readily re-
moveable, and when worn can be easily renewed.
Fig. 1 of the Drawings shews in side elevation one of my improved milla arranged
for once grinding; Fig. 2 is an end view partly in section; Fig. 3 is a plan partly
in section.
1, 1, are bevilled or conical annular grinding faces, which may be of hard cast
iron, properly turned to the required bevil or conical form. These grinding faces
are arranged back to back, and fastened (so as to be adjustable) by screw studs 2 to
the lugs or parts 3ª of the arms 3 radiating from the nave or boss 3b, keyed or
fastened on the shaft 4; 5, 5, are similar bevilled or conical annular grinding faces
arranged face to face and fastened (so as to be adjustable) by screw studs 6 on the
arms 7 radiating from the naves or bosses 7, keyed or fastened on the shaft 8.
The respective sets of arms of the two grinding faces 5 constituting the pair are
kept at a proper distance apart by stay rods 30, as shown. The shafts 4 and 8 are
driven in opposite directions, as indicated by the arrows, and the speed of one some-
what exceeds that of the other.
The relative speeds may be varied to suit circumstances.
The shafts are shewn provided with pullies, so that shaft 8, which may be driven
from any suitable source, communicates motion through two belts to shaft 4, causing
it to rotate somewhat slower. Other well-known means may be employed for com-
municating motion from shaft to shaft. The distance apart of the shafts is
adjustable. Each shaft is carried in bearings 10, capable of sliding on the beds 11.
The bearings of the shaft 8 are adjustable by screws 12 to compensate for wear of
bearings.
The bearings of the shaft 4 are set up as required to suit the work to be done by
a setting screw 13, through a cross head 14, rods 15, and springs 16, which act
under compression between the sliding bearings and collars 17 on the rods 15, as
shewn. Substances to be ground are supplied by a hopper 18, with feed rollers 20,
the feed being regulated by a feed slide 21, adjustable by a screw 22 and hand
wheel 23. The feed rollers are driven by belts from the pulleys 24 passing over
the guide pulleys 25.
Fig. 4 shews in section two modified ways of securing the grinding faces on the
shafts. In the arrangement shewn to the left, the body on which the grinding face
is fixed resembles a disc with a central boss 27 keyed on the shaft, and a rim 28
forming a shoulder to receive an annular projection 29 of angular section, cast or
formed at the back of the bevilled or conical grinding face.
In the arrangement shewn to the right, the boss and disc or body are cast or
formed with the bevilled or conical grinding face. Such discs or bodies, whether
both alike or not, are connected together by stay rods to keep the grinding faces at
the proper distance apart.

page_text: Having described the nature of my said Invention, and explained the manner of
carrying it into practical effect, I hereby declare that what I consider to be novel
and original, and therefore claim as secured to me under the Letters Patent herein-
before in part recited is,-
1. Arranging bevilled or conical grinding faces on axes placed parallel to each
other, with the larger circumferences of the grinding faces on one axis opposite the
smaller circumferences of the grinding faces on the other axis, the two axes being
driven in opposite directions substantially as described.
2. Arranging bevilled or conical grinding faces in pairs on axes parallel to each
other so that two such grinding faces arranged back to back on one axis shall work
between two other such grinding faces arranged face to face on the other axis sub-
stantially as described.
3. Constructing grinding mills substantially as herein-before described with
reference to the accompanying Drawings.
In witness whereof, I, the said John Pickering, have hereunto set my hand
and seal, this 15th day of August, in the year of our Lord One thousand
eight hundred and seventy-eight.
JOHN PICKERING. (L.S.)