Grinding or Pulverizing Flint and other Substances.
Year: 1888

page_text: Grinding or Pulverizing Flint and other Substances.
I, WILLIAM BOULTON, of Providence Foundry, Burslem, Staffordshire, Engineer,
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:-
This Invention relates to certain improvements in the method of and in or applicable
to that class of machinery or apparatus for grinding or pulverizing flint, stone, spar,
glaze, clay, color and other similar substances, in which the grinding is effected within
a revolving closed chamber by means of a quantity of contained balls or equivalent
means to which a continuous rolling motion is imparted by the revolution of the
chamber.
On the accompanying drawings; Fig. 1. represents an external elevation of the
herein described improved formation of pulverizing chamber. Fig. 2. represents the
sume in longitudinal section. Fig. 3. is a sectional view of the manhole opening and
cover through the line a-b, Fig. 1. and Figs. 4 and 5 are face and sectional views
respectively of the driving clutch.
In accordance with the present improvements; the chamber, 8, is made of a
spheroidal formation so that in all sections it at all parts of its interior presents a
curved surface; this is of especial advantage in causing a better concentration of the
material to be ground and of the pulverizing balls, pebbles or analogous means
used and a speedier reduction of the material to a pulverized condition. Such
improved formation is also of especial advantage in facilitating the lining of the
interior in a manner which will cause the interlocking of the paving stones and their
desired fixation without the need of the varied special means heretofore employed for
such purpose.
I construct the said chamber of such improved formation by casting the same in
iron or other suitable material in two half-parts which are alike as regards their
interior formation, and are each cast integral with an end supporting trunnion, 9, of a
solid formation or of a hollow formation for the purpose hereinafter referred to, and
are each also cast integral with a surrounding flange, 10, by means of the two of
which latter the said parts can be united together by screw bolts and nuts 11. One
part of the chamber, 8, is also cast with a surrounding belt-surface, 13, which is truly
turned, and the other part of the casing is formed with a manhole-opening, 14, by
which access to the interior of the chamber can be conveniently obtained.

page_text: If the apparatus is required for the grinding of substances which are required to be
kept from contact with the iron of the chamber, 8, the said half-parts of the latter are
also each cast integral with internal ribs or a continuous raised part, 12, adjacent to
the axis of the chinber forming a base from which the lining of the interior of the
chamber can be most conveniently effected with hard granito paving-stones such as
are quarried in Wales and Derbyshire or with any other suitable hard substance, as
at, 15, the same boing built between the said ribs, 12, and against the same as a base
and following the contour of the interior of the casing presenting a curved formation
in all sections of the chamber, thus ensuring a complete interlocking of the paving
stones, which are, moreover, hedded in cement, plaster or ground flint in a plastic
state or in any other suitable substance which after setting will form a solid mass and
will together with the said ribs and the interlocking of the stones due to the peculiar
interior contour of the chainher, 8, securely hold the paving stones, 15, in position
leaving on the inside a flush surface of the contour of the interior of the chamber.
16, represents a hole in the manhole cover, 17, through which the material to be
ground is fed into the chamber and which hole is adapted with a removable screw
plug, 35. The rim, 18, surrounding the manhole opening, 14, is cast with a
surrounding recess, 19, and the cover, 17, is formed with a corresponding pro-
jection, 20, between which and the recess, 19, strips, 21, of india-rubber, gutta-percha
or other suitable material are inserted to ensure a tight joint upon the lid being
scrowed down which is or may be effected in a usual manner by screw pius. 22,
passing through cross-hars, 23, which are carried by the cover and engage with
recessed lugs, 24, rising from the outer surface of the chamber, 8.
The said chamber as thus adapted, is supported in suitable standards, 25, and is
revolved by a belt or strap from a clutch pulley, 26, on a counter-shaft, 27. Or the
cylinder may he cast integral with a surrounding ring of spur teeth and driven by
gearing and fast and loose pulleys.
The shaft, 27, in the arrangement represented in Figs. 4, and, 5, is made in two
parts to one of which the clutch pulley, 26, is keyed at, 28, and to the other of which
is keyed at, 29, a casting, 80, formed with radial T-shaped recesses, 31, preferably
three in number and within each of which is arranged an inner projecting part of a
sliding block, 32, which is connected by steel springs, 38, to a sliding clutch, 34, on
the shift, 27, the series of blocks, 82, being slid by the movements of the clutch, 34,
against or away from the inner periphery of the pulley, 26, as required. The
shaft, 27, can be in one part by letting the pulley, 26, run loose on the shaft when not
in action.
In lieu of proceeding with the grinding of the materials in the modes at present
practiced according to one of which the materials are kept in the rotating cylinder
until the whole contents are reduced to the required degree of fineness which involves
a considerable waste of power and of time owing to the retention within the cylinder
of the sufficiently ground material until the remainder of the material is reduced to
the same condition; and according to another of which the materials are kept for a
given time in the rotating cylinder and are then run off from the bottom into wash-
tubs, the insufficiently ground together with the sufficiently ground, after which that
portion which will not remain in suspension in the water is returned to the cylinder,
which also involves a needless waste of time, I proceed with the grinding of the
materials, in the following improved manner.
I place a quantity of the material to be ground (after having been granulated, if
necessary, between one or more pairs of rollers formed of chilled corrugated iron or of
hard granite, or otherwise,) through the said opening, 16, into the chamber among
tho contained balls or like means, and also introduce into tho chamber
desired
any
quantity of water or other suitable liquid through the said opening or the said hollow
trunnion, and cause the chamber to revolve for such a time as will ensure that a good
proportion of tho material will be sufficiently ground. then pump or otherwise
introduce into the chamber through the said hollow trummion or otherwise a further
quantity of water or other liquid sufficient to render the contained material so
liquefied as that the rougher and insufficiently ground particles will sink to the

page_text: bottom leaving the sufficiently ground particles in suspension; after being allowed to
stand for a short time the added water is drawn off through the said opening, 16, or
by means of taps or other suitable outlets, 36, at a suitable height above the sediment
of the rougher parts, and carries with it the sufficiently ground particles in suspension,
after which I add to the partly ground contents of the chamber about the same
quantity of material to be ground as that withdrawn as sufficiently ground and
proceed with the grinding until a further portion is ready for being withdrawn in
such manner as aforesaid, and so on.
I also facilitate the grinding operation by heating or causing the liquid in which
the materials are ground to boil by passing superheated or wet steam into the
chamber, 8, during the rotation thereof or when stationary introducing hot water or
steam through the said hollow trunnion if the apparatus be constructed therewith by
means of suitable connections adapted with proper usual means of proventing any
undue pressure, or while the chamber is stationary introducing the steam or hot water
through a suitably adapted opening made in any convenient part of the chamber.
By such improved method of operation, the whole product is caused to be of an
even fineness and I avoid the waste of time, labor and power attendant upon the said
present methods of operation.
When it is wished to grind the materials in a dry condition, I remove the same
from the chamber, 8, in a usual manner through a circumferential grating adapted to
the said manhole.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
The hereinbefore described improvements in the method of and in or applicable to
machinery or apparatus of the class described for grinding or pulverising flint and
other substances; such improvements consisting in-
1. The construction of the grinding chamber of a spheroidal formation by casting
the same in half parts integral with solid or hollow supporting trunnions, surrounding
flanges and belt or driving surface or toothed rim and with a manhole adapted with a
recessed rim, substantially as herein before described.
2. The construction of the grinding chamber of a spheroidal formation by casting
the same in half parts integral with solid or hollow supporting trunnions, internal
lining-supporting ribs, surrounding flanges and belt or driving surface or toothed
rim, and with a manhole adapted with a recessed rim, substantially as hereinbefore
described.
3. A grinding or pulverising chamber of the improved formation and construction
hereinbefore described and claimed in claim, 2, in combination with an interlocking
cemented lining built with paving stones against the said ribs as a base and following
the spheroidal formation of the chamber, substantially as hereinbefore described.
4. The formation of the grinding chamber integral with a surrounding belt or
driving surface or toothed rim substantially as bereiubefore described.
5. The application of the hereinbefore described improved arrangement of driving
clutch to the purpose of the Invention.
6. The herein before described improved method of operation in effecting the wet
grinding of the materials under treatment.
Dated this 22nd day of June 1888.
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C.,
Agents for the Applicant.