Improvements in Mills for Crushing or Pulverizing Ores and other Substances.
Year: 1890

page_text: Date of Application, 15th Oct., 1890
Complete Specification Left, 4th July, 1891-Accepted, 15th Aug., 1891
PROVISIONAL SPECIFICATION.
Improvements in Mills for Crushing or Pulverizing Ores and other
Substances.
I, WILLIAM HENRY COWARD of Newark House, Railway Place, Bath, in the
County of Somerset, Engineer and Machinery Broker, do hereby declare the
nature of this invention to be as follows:-
This invention relates to improvements in, and connected with, the crushing
mill, for pulverising ores and other hard minerals or substances, for which previous
Letters Patent were granted to me dated March 27th 1889, No. 5286.
The said mill consists essentially of an edge runner rolling within a drum
revolving upon a horizontal axis so as to pulverize the material which is repeatedly
brought under its action by cups fixed to the drum, the edge runner being kept in
its true path in the drum by a shaft anchored in a swivel bearing, and loaded by an
adjustable weight or spring to increase the crushing power of the edge runner.
anti-friction
the said former machine the drum was wholly supported directly upon
rollers beneath its periphery and had a long tubular shaft turning in two bearings
taking no part of the weight and serving only to keep the drum upright.
In
The object of my present improvements is to reduce the dimensions and weight,
augment the crushing power, and improve the operation of the mill, and facilitate
the separation and extraction of light particles without the use of sieves.
My said improvements relate chiefly to the mode of mounting the drum; to the
use of two or more crushing rollers working in the same drum.
According to one arrangemement of my improved mill, the drum is supported
partly upon a short gudgeon and partly by the flange around the feed mouth
cradled in a set of three friction rollers so that the weight of the drum is about
equally divided between the gudgeon bearing and the friction rollers. The friction
rollers are flanged and, together with the gudgeon, resist endwise movement of the
drum. By this arrangement, the space occupied and the velocity of the friction
rollers are much reduced, the friction rollers are more conveniently mounted on the
base plate and are more accessible for lubrication, etc. The feed mouth of tho
drum, instead of being open, is closed by a stationary cover carrying a hopper. In
order to increase the efficiency of the mill, more than one crushing roller is used,
two or three such rollers running on the same path in succession, the shaft of each
roller, whether one or more be used, passing through a slot in the cover of the drum.
According to another, and preferred, arrangement, by which the working
capacity of the machine is doubled with a relatively small increase in weight
cost and driving power, the drum is made of double width and has a mouth at cach
side closed by a cover and contains two sets of edge runners working side by side,
each set being one, two, or three, in number and carried upon oppositely-projecting
shafts passing through the opposite covers of the drum. The drum has three sets
of elevating cups, the middle set being of double capacity and situated between the
two sets of edge runners. The one cover of the drum is provided with the feed
hopper before described and the other cover is connected in such manner with an
upwardly-extending pipe leading to the exhaust fan that only the impalpable
powder and particles of extraneous material of low specific gravity can be carried
to the fan, any insufficiently-crushed pieces which may be carried into the exhaust
pipe falling back into the casing.
D
1 1
CO- 1900
W. H. COWARD.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.

page_text: COMPLETE SPECIFICATION. Y
Improvements in Mills for Crushing or Pulverizing Ores and other
Substances.
I, WILLIAM HENRY COWARD of Newark House, Railway Place, Bath, in the
County of Somerset, Engineer and Machinery Broker 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:
This invention relates to improvements in, and connected with, the crushing mill
for pulverizing ores and other hard minerals or substances for which previous
Letters Patent were granted to me dated March 27th 1889 No. 5286.
The said mill consists essentially of an edge runner rolling within a drum
revolving upon a horizontal axis so as to pulverize the material which is repeatedly
brought under its action by cups fixed to the drum, the edge runner being kept in
its true path in the drum by a shaft anchored in a swivel bearing and loaded by an
adjustable weight or spring to increase the crushing power of the edge runner. In
the said former machine the drum was wholly supported directly upon anti-friction
rollers beneath its periphery and had a long tubular shaft turning in two bearings
taking no part of the weight and serving only to keep the drum upright.
The object of my present improvements is to reduce the dimensions and weight,
augment the crushing power, and improve the operation, of the mill and facilitate
the separation and extraction of light particles without the use of sieves, by
winnowing the material whilst under treatment.
Reference is to be had to the accompanying drawings, formning part of this
Specification; wherein
Figure 1 is an axial vertical section of a single form of mill having one edge
runner.
Figure 2 is a similar view of a double form of mill in which two sets of edge
runners roll on different paths in the drum.
Figure 3 is a front elevation (with the cover removed) of either of the above
forms of mill.
Figure 4 is a similar elevation of either of the above forms of mill when provided
with a set of three edge runners rolling on the same path in the drum or with two
such sets on different paths as in the double form of mill shewn in Figure 2.
The same letters of reference denote like parts in all the figures.
A is the drum revolved on a horizontal axis by peripheral spur gearing, B is or
are the edge runner or runners rolling within the drum, and C are sets of elevating
cups fixed within the drum near the periphery so as to pass at either side of the
edge runner, as in Figure 1, or at either side of and between the two sets of edge.
runners, as in Figure 2, their mouths being towards the direction of rotation of.the
drum in order to catch the material after it has been operated on and carry it up
and throw it down in front of the edge runner or runners to be operated upon again
and to at same time expose it to the winnowing action of the exhaust current of
air. Each edge runner B is fixed to the end of a shaft D which passes out of the
drum through a large circular opening in the side thereof and is journaled at its
outer end in a universal or swivel bearing E which embraces the journal between
shoulders and has lateral gudgeons e pivoted in a rigid bracket F the shaft D being
thus firmly anchored to the base plate so that whilst the edge runner and shaft are
free to revolve the edge runner is prevented from deviating from its path but is
free to rise and fall on passing over the roughly-broken material, the slight lateral
motion of the edge runner due to angular motion about the axis e of the swivel
bearing E having the effect of supplementing the crushing action of the edge
runner by an abrasive or. rubbing action between the edge runner and the drum
which conduces to the reduction of the material to an impalpable powder. Each
shaft D. is. guided by a bearing-y free.tu. rise and fall in guides & radial to the

page_text: drum, the bearings being loaded by a spring H regulated by screws / in order to
increase the crushing power of the edge runner. The opening in the side of the
drum giving passage to the shaft or shafts D is surrounded by a flange I which is
cradled upon a set of friction rollers J carried by shafts turning in bearings j. fixed
to the bed plate.
•
In Figure 1 the drum contains but one edge runner and is supported partly by a
set of rollers J and partly by a gudgeon K turning in a bearing. The aperture
surrounded by the flange I is closed by a stationary cover L provided with a slot
to give passage to the shaft D and with a feed hopper M leading through said
aperture into the drum. The drum journal K is tubular and is covered on the
inner side by a sieve and to it is connected a pipe leading to an exhaust fan by
which a current of air admitted at the feed hopper is caused to traverse the drum
and to winnow the crushed material falling from the cups C and extract the finely-
crushed particles.
In order to increase the efficiency of the mill more than one edge runner may be
used, as in Figure 4 in which there are three rolling on the same path in succession
and whose shafts are all anchored and guided as before described so as to permit of
bodily motion of the rollers only in planes radial to the drum axis.
The double form of mill shewn in Figure 2 has a greatly increased working
capacity the drum A being made of double width and containing two sets of edge
runners B working side by side on different paths the shafts D of the two sets
projecting through openings in the opposite sides of the drum each shaft being
anchored and guided as above described and each set comprising one edge runner,
as shewn in Figure 1, or several runners, as shewn in Figure 4. The drum has a
Hauge I at each side, said flanges I being cradled in two sets of rollers J upon
which the drum is thus wholly supported. The drum has three sets of elevating
cups a set C fixed to each side of the drum as before and a middle set C' fixed to
the periphery of the drum and passing between the two sets of edge runners, the
cups Cbeing larger than the cups C. The cover Lat one side of the drum is
provided with a feed hopper M as before whilst the other cover N has an aperture
at the upper part leading through an upwardly-extending and gradually contracted
spout O into a vertical pipe P which is carried up to about the level of the top of
the drum A and then to an exhaust fan so that only impalpable powder and any
large particles of extraneous matter of low specific gravity will be carried off. By
this upward draught I am enabled to dispense with sieves over the exhaust aperture
which are liable to become clogged by light particles in operating on micaceous
ores for example.
1
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
1. The hercin described pulverizing mill comprising a drum mounted to revolve
on a horizontal axis by a flange at one side cradled in friction rollers and a hollow
journal bearing at the other side, the drum being furnished with internal cups, in
combination with one or more edge runners rolling on the same path within the
drum, each fixed to a shaft passing through an aperture at one side of the drum
and anchored in a swivel bearing and radially guided by a spring pressed bearing
permitting rotary and angular motion of the runner, substantially as specified.
2. The herein described pulverizing mill comprising a drum mounted to revolve
on a horizontal axis by flanges at both sides cradled on sets of friction rollers and
furnished with three sets of internal cups in combination with two sets of edge
runners rolling side by side on different paths within the drum and between
different sets of cups each set of edge runners comprising one or more runners each
attached to a shaft anchored in a swivel bearing and radially guided by a spring
pressed bearing permitting rotary and angular motion as described the shafts of the
two sets passing through apertures at opposite sides of the drum substantially as
specified.

page_text: 3. The combination with the herein described pulverizing mill having apertures
at each side as described in reference to Figure 2, internal cups and one or more
sets of edge runners mounted and guided as described, of stationary covers fitting
said apertures as described and carrying the one a feed hopper and the other an
upwardly directed exhaust pipe substantially as and for the purpose specified.
Dated this 3rd day of July 1891.
W. H. COWARD.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.