Improvements in Machinery for Pulverizing Ores or other Substances.
Year: 1894

page_text: Date of Application, 18th Oct., 1894-Accepted, 24th Nov., 1894
COMPLETE SPECIFICATION.
Improvements in Machinery for Pulverizing Ores or other Substances.
I, PETER B. BRADLEY, of 92, State Street, Boston, Mass.,. United States of
America, Engineer, do hereby declare the nature of this invention, and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement, and accompanying drawings, that is to say :-
The present invention relates more especially to the pulverizing machine for
which a patent was granted to Edwin Packard, dated March 8th A.D. 1889,
No. 4117, for "Improvements in machinery for pulverizing ores or other hard
substances."
It has for its object improved methods of constructing and combining the parts
of such pulverizing machines in which a rapidly revolving roller is pressed by
centrifugal force against the inner periphery of a hard fixed ring, by which the
machine is rendered much stronger, more effective and durable, and the material to
be treated is fed automatically to the machine at the proper speed.
In the accompanying drawings,
Figure 1 is a vertical section through a complete machine adapted for the dry
grinding of hard ores and the like.
Figure 2 is a plan of the upper part of the pulley by which the spindle of the
crushing roller is suspended, and driven round.' Figure 3 is a vertical section
through the same, and Figure 4 a half vertical section through the line a―y in
Figure 2.
Figure 5 is a partial vertical section of the same machine modified so as to be
adapted for wet grinding.
The power from a steam engine or other source is received by a pulley a running
borizontally. From this pulley the roller shaft 6 is suspended by a universal joint,
and to the lower extremity of this shaft the crushing roll is rigidly fixed, and is
thus free to swing in any direction within the case of the machine. This case consists
of the base or pan d containing a hard ring e against which the roll e works, and
upon the inner vertical surface of which the pulverizing is done. The pan or base d
has a sufficient number of openings downward, f, which lead into a pit or receptacle
below. Upon the base is fixed the screen frame g, upon the cover of which is fixed
the conical shield h open above, through which the roll shaft works. Upon the
shaft b, just above the roll c is fixed a frame carrying fan blades k, and below the
roll are fixed agitating shoes or ploughs 1 the shape of which may be varied
according to the nature of the work to be done.
The pulley a revolves upon a tapered and adjustable bearing as shewn in
Figures 1, 2, and 4.
The body of the pulley is shewn at m, and upon it is fixed
the wooden rim n. The shaft bis suspended in the pulley by the ball o and
trunnions fixed
P,
upon its upper
end by a nut r, the trunnions p being driven round
by half boxes fitting upon them and capable of moving up and down in recesses &
(Figure 2) against steel plates t.
The universal joint is composed of the ball or sphere e, with trunnions p, p,
attached thereto. These trunnions are at right angles to the suspended shaft b, so
that when the latter is hanging vertically, the trunnions are horizontal. When,
however, the shaft b departs from its central vertical position, and the roll c.is
pressed by centrifugal force against the ring or die e, the trunnions will be also
inclined, one being raised, and the other lowered, and to enable this to take place,
the half boxes in which the trunnions fit, are made capable of rising and falling
in recesses a, 's in the pulley head casting m in which they are fitted, (Figures 2, 3
and 4). The revolution of the pulley head m drives round the half boxes, and

page_text: with them the trunnions, without preventing their movement up and down. As the
trunnions are always driven round in the same direction, half boxes only are
necessary, fitting against the back of the trunnions where the driving pressure is
exerted. On starting the mill the roll c hangs vertically and centrally whilst
revolving, but upon moving it by hand slightly out of the vertical line, centrifugal
force at once carries it forcibly out against the ring or die e and grinding commences
and continues as long as the driving pulley a revolves.
The ball o is carried in the step u upon the body m of the pulley, the lower part
of which is formed with an internal cone which fits upon a corresponding cone v
(with the intervention of an anti-friction lining), the latter being formed with a
turned-up flange at its lower end which is screwed inside so as to be screwed upon
the externally screwed cylinder y, the upper end of which is screwed into the ring z,
(which is preferably split at one side to give it elasticity), a flange upon the upper
end of which is carried by the upper ends of the standards 1, 1, of the machine.
The lower end of the conical bearing is provided with bosses, into which are
screwed set-screws (with lock nuts), 2, which press against the lower end of the
cylinder and hold the bearing firmly in its place when it has been properly
adjusted. Thrust rings 3 of steel and of anti-friction composition alternately, are
inserted under the lower end of the hollow revolving internal cone, to reduce the
friction of the latter.
ولا
The upper part of the hollow body m of the pulley is closed by a cover 5, and a
steel ring 6 is fitted upon the upper part of the ball o and is kept pressed against
it by a spring 7 inserted between the ring 6 and the cover 5.
Upon the upper part of the cover 5, is formed a set of hollow cone speed pullies 8,
the central bore of which turns, with the intervention of an anti-friction lining,
upon a pin 9 which is firmly fixed into a strong bracket 10 carried by prolongations
upon the standards 1. The pin 9 is hollow, and is provided with channels for
lubrication.
A second light bracket 11, carried by the bracket 10 has at its outer end a bearing
in which revolves the upper end of a vertical feeding spindle 12 which carries cone
pullies 13 driven at the required speed by a cord from the pullies 8 already described.
14 is a hopper from which the material to be pulverized is fed uniformly into the
mill by means of a feeding screw 15 revolving in the chamber 16 connected with the
hopper, its axle turning in a bearing 17 carried by the hopper support, and having
fixed upon it a bevelled toothed wheel 18 gearing with a corresponding pinion 19
upon the lower end of the spindle 12 which turns in a bearing 20 upon the top of
the bearing 17. A shifting clutch 21 allows the pinion 19 to be disengaged from the
wheel 18 when desired. A sliding door 22 enables the opening from hopper to be
closed or regulated, and a moveable cover 23 affords access when necessary to the
feeding screw 15. A passage 24 delivers the material just inside the upper edge of
the grinding ring e. The pulverized material is removed from below the pan by
conveyors or other means.
By the novel methods of construction described and shewn, the bearing surfaces
of the driving apparatus are completely protected from dust and dirt, and are
perfectly and accurately adjustable so as to be very durable. The material to be
pulverized, (after having been reduced to a certain size) is supplied regularly and
uniformly, and the output is very large, and by means of the revolving fan blades k,
a current of air is caused, which is drawn in through the conical casing h, and
prevents any escape of dust.
When the material is to be pulverized wet instead of dry, the modification shewn
in Figure 5 is used. In this the water is introduced into the mill with the material
fed in, and when the mill is running the water has the same motion as the material
in the dry mill first described, carrying with it the ore or other material, both coarse
and fine. The fine material which together with the water forms a pulp, passes
through the screens into the surrounding trough A, from one side of which it is
discharged through the spout B, whence it may be passed over plates, or into an
amalgamator or concentrator, as desired.

page_text: By the construction of the mill described, the lubricating oil is prevented from
ixing with the pulverized material.
Having now particularly described and ascertained the nature of my said inven-
on, and in what manner the same is to be performed, I declare that what I
laim is :-
1. In a pulverizing machine characterized by a roll pressed by centrifugal force
gainst a fixed ring
(1) The ball o and trunnions p, recesses 8, and plates t, spring 7 and cover 5,
and central pin 9, pulley n, hollow coned body m, screwed bearing cone v,
adjustable by means of the screwed cylinder y, and screwed supporting
ring z, friction plate 3 and fixing screws 2, substantially as and for the purpose
described and illustrated.
(2) In dry pulverizing mills, in combination with the apparatus claimed in the
first claim, the fans k upon the roll spindle b, the hollow cone h, hopper 14,
feeding screw 15 driven by the toothed wheels 18, 19, spindle 12 and
pullies 8, 13, substantially as described and illustrated.
(3) In wet pulverizing mills, the modified method of construction consisting
of the combination with the apparatus claimed in the first claim, of the
annular trough A and discharge spout B, substantially as and for the purpose
described and illustrated in Figure 5.
Ontbox 1894
EDWARDS & Co.,
65 and 66, Chancery Lane, London, Agents for the Applicant.