IMPROVEMENTS IN EDGE MILLS FOR THE PULVERIZATION OR GRANULATION OF HARD SUBSTANCES
Year: 1882

page_text: LETTERS PATENT to Benjamin Joseph Barnard Mills of the firm of Harris
and Mills of 23 Southampton Buildings in the County of Middlesex,
Patent Agent for an Invention of IMPROVEMENTS IN EDGE MILLS FOR THE
PULVERIZATION OR GRANULATION OF HARD SUBSTANCES Communicated
to him from abroad by Francis Wanneveich of Cours Berriat, Grenoble,
Isère in the Republic of France, Engineer
"
PROVISIONAL SPECIFICATION left by the said Benjamin Joseph Barnard
Mills at the Office of the Commissioners of Patents on the 26th June 1882.
BENJAMIN JOSEPII BARNARD MILLS of the firm of Harris and Mills of
23 Southampton Buildings in the County of Middlesex, Patent Agent
IMPROVEMENTS IN EDGE MILLS FOR THE PULVERIZATION OR GRANULATION OF
HARD SUBSTANCES." A Communication to mne from abroad by Francis Wanneveich
of Cours Berriat, Grenoble, Isère in the Republic of France Engineer
In the working of edge mills employed in crushing or reducing to powder hard
substances, the first turns of the runner by pounding the larger picces produce in
abundance a powder more or less fine into which the non-pulverized pieces sink
and thus partly escape the action of the runner. The work then becomes very
slow, it is necessary frequently to return the material, and there is finally obtained
only a mixture of fine powder with a great quantity of larger materials which it
is necessary to return to the edge mill after sifting or bolting.
By the present Invention these inconveniences are avoided and the production
is greatly increased with the same expenditure of power, by rendering the work
continuous and by dividing it between several edge runners working upon con-
centric ways around the same vertical shaft, the substances passing from the one
to the other of these ways as they recede from the centre.
The most simple arrangement consists in arranging these ways in circular steps.
The substances are delivered to the centre by a distributor which delivers them

page_text: equally all around the circumference, the fall from there on to the first step
where they commence to be crushed, then pushed by the delivery of fresh materials
and by the action of the runner aided by the action of mechanical means, they fall
gradually upon the next step where they are again treated by the second runner
and so on to the last step where having acquired the desired degree of fineness
they fall into a circular trench or trough whence they are continuously cleared
away by a collector which turns with the runners and delivers them to elevators
leading to seives or bolting apparatus.
The ultimate nature of the product will depend upon the speed of the feed and
it will be finer in proportion as it remains a longer time under treatment.
In this system each runner acting constantly upon substances of nearly uniform
size and in layers of small depth does much superior work to that of a runner
working under the usual conditions and as on the other part the continuous feed
and discharge of the substances avoids all stoppages in the work, the production is
considerably increased at the same time that the work is more perfect.
The distribution of the substances at the centre of the apparatus can be effected
by various means.
According to one arrangement at the upper part of the apparatus is a hopper
opening into the interior of a cylinder either horizontal or slightly inclined, and
furnished with a slow rotary motion.
The substances thrown into the aforesaid hopper by barrows, carts or waggons
according to the size of the apparatus are drawn forward by the motion of the
cylinder and then fall into a second hopper which turns with the central shaft
and distributes the materials, by one or several mouths, to the circumference of the
central platforin. The feed is regulated by the speed given to the cylinder and
can be entirely stopped by the stoppage of said cylinder.
In certain cases it may be useful in order to counteract the effects of centrifugal
force, to incline the steps towards the centre to an extent regulated according to
the speed of the runners the bed can then be horizontal or by suppressing the
steps it can be conical.
The runners can also be caused to work in circular grooves of different sections,
one of the faces of which would support the pressure due to centrifugal force.
In all these arrangements and in all that may be derived from them, the
passage of the substances from one path to the other can be facilitated by
collectors of various forms according to the applications and turning with the
runners.
To granulate hard bodies such as quartz and at the same time to prevent any
considerable production of dust injurious to the quality of the products, the steps
can be formed with gratings gradually finer as they recede from the centre, the
materials pass through these gratings as soon as they have attained the desired
size and fall upon a conical surface which conducts them to the next step
and so on to the last which delivers the material in uniform grains of the size
desired.
The first steps can also be formed with gratings to commence the operation
and the latter can be finished by reducing the substances to powder upon solid
steps.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Benjamin Joseph Barnard Mills in the Great Seal Patent Office
on the 22nd December 1882.
BENJAMIN JOSEPH BARNARD MILLS of the Firm of Harris and Mills of
23 Southampton Buildings in the County of Middlesex Patent Agent " IMPROVE-
MENTS IN EDGE MILLS FOR THE PULVERIZATION OR GRANULATION OF HARD
SUBSTANCES
(A Communication to me from abroad by Francis Wanneveich
of Cours Berriat Grenoble Isère in the Republic of France Engineer)
In the working of edge mills employed in crushing or reducing to powder hard
substances the first turns of the runner by pounding the larger pieces produce in
abundance a powder more or less fine into which the nonpulverized pieces sink and
thus partly escape the action of the runner. The work then becomes very slow,
it is necessary frequently to return the material, and there is finally obtained only
a mixture of fine powder with a great quantity of larger materials which it is
necessary to return to the edge mill after sifting or bolting.
By the present invention these inconveniences are avoided and the production is
greatly increased with the same expenditure of power by rendering the work
continuous and by dividing it between several edge runners working upon con-
centric ways around the same vertical shaft the substances passing from the one to
the other of these ways as they recede from the centre.
The most simple arrangement consists in arranging these ways in circular steps
as represented at Figures 1. and 1ª.
The substances are delivered to the centre by a distributor D which delivers
them equally all around the circumference, they fall from there on to the first step
where they coininence to be crushed then pushed by the delivery of fresh materials
and by the action of the runner aided when required by the action of mechanical
means, they fall gradually upon the next step where they are again worked by the
second runner and so on to the last step where having acquired the desired degree
of fineness they fall into a circular trench or trough E whence they are con-
tinuously cleared away by a collector F which turns with the runners and delivers
them to elevators leading to sieves or bolting apparatus.
The ultimate nature of the product will depend upon the speed of the feed
and the product will be finer in proportion as it remains a longer time under
treatment.
In this system each runner acting constantly upon substances of nearly uniform
size and in layers of small depth does much superior work to that of a runner
working under the usual conditions and as on the other part the continuous feed
and discharge of the substances avoids all stoppages in the work the production is
considerably increased at the same time that the work is more perfect.
The distribution of the substances at the centre of the apparatus can be effected
by various means one of which is represented at Figures 1 and 1º.
At the upper part of the apparatus is a hopper A opening into the interior of a
cylinder B either horizontal or slightly inclined and furnished with a slow rotary
motion. The substances thrown into the aforesaid hopper A by barrows carts or
wagons according to the size of the apparatus are drawn forward by the motion
of the cylinder and then fall into a second hopper C which turns with the central
shaft and distributes the materials by one or several mouths D to the circum-
ference of the central platform-The feed is regulated by the speed given to the
cylinder B and can be entirely stopped by the stoppage of said cylinder.
In certain cases it may be useful, in order to counteract the effects of centrifugal

page_text: or
force, to incline the steps towards the centre to an extent regulated according to
the speed of the runners the bed can then be horizontal as shown at Figure
by suppressing the steps it can be conical as shown at Figure 3-The runners can
also be caused to work in circular grooves of different sections as shewn at Figure 4
one of the faces of which would support the pressure due to centrifugal force.
In all these arrangements and in all that may be derived from them, the passage
of the substances from one path to the other can be facilitated by collectors of
various forms according to the applications and turning with the runners.
To granulate hard bodies such as quartz and at the same time to prevent any
considerable production of dust injurious to the quality of the products, the steps are
formed with gratings gradually finer as they recede from the centre as shown at
Figure 5 the materials pass through these gratings as soon as they have attained
the desired size and fall upon a conical surface which conducts them to the next
step and so on to the last which delivers the material in uniform grains of the
size desired
The first steps can also be formed with gratings to commence the operation and
the latter can be finished by reducing the substances to powder upon solid steps
Having thus described the nature of the said invention and the mode in which
the same is carried into effect I would have it understood that whatever may be
the arrangement adopted I claim in edge mills employed for crushing granulating
or pulverizing hard substances,
First The application of several runners turning upon concentric paths around
the same vertical shaft.
Second-The successive passage of the substances from one to the other of these
paths either by their natural fall or by mechanical means such as guides or
collectors of forin suitable to the various cases.
In witness whereof I the said Benjamin Joseph Barnard Mills have hereunto
set my hand and seal this Twenty second day of December in the year of
our Lord One thousand eight hundred and eighty two.