Improvements in and relating to Grinding or Crushing Mills of the Class known as Chasing Mills.
Year: 1892

page_text: Date of Application, 30th Nov., 1892-Accepted, 28th Jan., 1893
COMPLETE SPECIFICATION.
Improvements in and relating to Grinding or Crushing Mills of the
Class known as Chasing Mills.
I, HENRY CUSHING HIGGINSON, a citizen of the United States of America,
residing at Newburgh, in the County of Orange and State of New York, one of the
United States of America, Manufacturer, 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 :-
Figure 1 shows a view partly in vertical section and partly in elevation of my
chasing mills, with a portion of one of the settling tanks;
Figure 2 a similar view of the mill, with the plane of section at right angles to
that of Figure 1, and the crushing wheel and the means for driving the vertical
shaft removed;
Figure 3 a view of a horizontal section on line x-x of Figure 1.
Letters of like name and kind refer to like parts in each of the Figures.
The object of my invention has been to provide an improved mill of the kind
known as a "chasing" mill in which one or more crushing wheels, rolling over a
suitable bed, are used to crush the material placed upon the latter, and to
this end-
My invention consists in the mill and the parts thereof, constructed, arranged and
combined as hereinafter specified.
The particular kind of chasing mill to which my invention specifically relates, is
that in which the crushing wheel or wheels work upon the material within a tank of
water, so that, as said material becomes finely pulverized, it is mixed with the water
and is carried over thereby from the crushing tank to suitable settling receptacles
or tanks, which, being successively reached by the water, will receive and retain, as
a deposit from the latter, successively finer and finer grades of the product produced
by the crusher.
Such mills have heretofore been used for the manufacture of whiting or Paris
white, but they have always, from their construction and operation, necessitated the
use of a large number of settling tanks.
In making my present invention, I have had in view the production of an
apparatus for making the substance above-named, which, while operating as rapidly
as the mills heretofore used, to crush and mix the pulverized material with the
water, will require a less number of settling tanks to produce a certain quantity of
the finest grades of whiting from a given quantity of raw material.
In order to facilitate the separation of the fine particles of material held in
suspension in the water, and to make unnecessary the use of a large number of
settling tanks, as indicated above, I interpose between the body of water in the
crushing tank, and the settling receptacles or tanks, certain mechanism which I will
hereinafter describe.
In the drawing A designates the tank within which the crushing is to be done,
while B designates the bed upon which the material is to be crushed.
Such bed, which is shown as circular, but can be of any other desired shape, so
that it is large enough to extend out beyond the circular path of the outer portion
of the crushing wheel or roller that may be used, as hereinafter set forth, is made of
stone or other hard material.
Upon a suitable step C on the central portion of the bed supported the lower
end of the upright rotary shaft D, which, at its upper end, is journalled in a
bearing E, on a beam E¹.
Below such bearing there is fixed on the shaft a bevel gear wheel D¹ which.

page_text: meshes with and is driven by the correspondingly shaped gear D² on the driving
shaft D³, which itself is to be connected with and driven by any desired form of
motor or actuating device.
Near its lower end the shaft is provided with the horizontal hollow cross head, D*,
preferably, but not necessarily, having the passage through it rectangular in cross
section.
As shown, it is, in such section, an oblong, with the longest diameter an upright
one.
Fitting between the sides of such passage is the squared bar F, which
of such height as to be capable of rocking up and down to a certain extent within
the passage.
In each side of the cross head D is a vertical slot d, which is engaged by a pin f
on the bar.
In the apparatus shown in the drawings, one end of the bar, beyond the cross
head, is provided with a cylindrical extension forming an axle F¹, to enter the
central axle opening in the crushing wheel or roller F2, preferably made of stone,
and weighted, if desired. Such wheel or roller rests and rolls with its whole weight
upon the bed B, or any material placed on the latter.
The bar F connected as it is, with the shaft D, does not act in any way to take
or support any of such weight, but simply has to force the wheel or roller onward,
so that it will roll over and crush any material placed below it.
The rocking connection between the shaft and bar serves to allow for any
rising and falling of the wheel or roller, as the material acted upon varies in
thickness.
The tank, which, of course, should be water tight, is, when in use, kept filled with
a body of water H, as shown, a supply pipe I, being provided, through which the
water can be continuously run in as desired.
At K, in the upper part of one of the tank sides is the outlet, which opening into
a suitable trough or conduit L leading to the first settling tank M, serves to allow
the overflow of water, filled with particles of the crushed material held in
suspension.
An outlet situated, as set forth above, so as to draw only from the upper part of
the body of water within the crushing tank, has been used in whiting or Paris white
machines, as heretofore made, and is not by itself new with me. But, in such
machines, I have found that the disturbance and stirring up of the water by the
crushing wheel or wheels will cause particles of material too coarse for use to be
carried out through such outlet into the settling tanks. This is the reason why so
many different settling tanks had to be employed in connection with the old
machines. Several of such tanks were needed merely to separate out the coarser
particles, which were not fine enough for the desired best grades of product.
This separating of the coarser particles outside of the crusher tank not only made
necessary the use of an objectionable number of tanks, but involved a waste of time,
in securing the settling of the too coarse portions of the material, an expenditure of
time and labor in clearing the first tanks of such portions, and a diminution in the
amount of the finer grades of product secured in the settling tanks, such diminution
being caused by a certain portion of the finer particles settling with and among the
coarser ones.
To avoid the above stated objections to the old machines, as heretofore made and
used, with the open outlet leading from the crusher tank to the settling ones, I
attach to that part of the tank casing which contains the outlet K, a dam N, which,
on the side away from the line of travel of the crushing wheel or roller, has its
upper edge cut down or lowered, as shown at n, so that the water in the upper part
of the crushing tank can flow over it, on its way.to the said outlet K.
This dam is preferably made as shown, in the form of a part box consisting
of three sides and a bottom, and having its open outer side closed by the
tank wall.
Except at n the upper edge of the box is carried up above the level of the liquid

page_text: in the crushing tank, so that the wheel or roller F2, as it rolls around, can not swash
such liquid over the box top into its interior.
In the bottom of the box or casing forming the dam are perforations n', n',
through which liquid and the coarser particles of material, which it is not desirable
to have reach the settling tanks, can pass.
Over the outlet K, I place a screen O, which can be made of wire cloth or
netting, or of a perforated plate of sheet metal, as desired, with its meshes or
perforations fine enough to keep back the particles of material which are too coarse
for use, while allowing the passage of the finer particles with the water in which
they are held in suspension.
To keep this screen clear and prevent it from being clogged, so that the
passage of the water and fine particles will not be impeded, I provide a brush P,
attached to a swinging arm P', so that it will rub back and forth over the inner face
of the screen, as the arm is swung.
A guide P² attached to the casing, as shown, engages the inner side of said arm,
so as to guide the latter in its movements and hold the brush up to its work on the
screen.
I do not limit myself to any particular form of brush, but contemplate using any
desired kind of the same, whether it has bristles, fine wires, or other material in
place of and to act like bristles.
For automatically swinging the arm to carry the brush back and forth across
the screen face, I contemplate using the gearing shown in the drawings, consisting
of a shaft R, which is driven from shaft D³, by a gear wheel R', on the latter
meshing with a corresponding gear R2 on the former shaft.
On the shaft R which is supported in the pendent bearing R³, which is attached
to any suitable beam or support R₁, is a crank arm R, which is connected by
link R, with the swinging brush carrying arm P', so that, as shaft R revolves,
said arm P¹, will be swung back and forth in the manner and for the purpose
indicated herein before.
While I have shown and described only one crushing wheel or roller, it will be
understood that two or more can be used instead, connected with the upright shaft
in the same way as the one shown, or otherwise, as desired, without involving any
departure from my invention.
I desire it also to be understood, that, while I have set forth the machine or
apparatus as applicable to the manufacture of whiting or Paris white, it can be
used also for the crushing of ore and other substances, which are to be treated in
the same way as the material from which whiting is made, that is by crushing in
water, carrying off in the latter the finer particles, and settling or separating them
in settling tanks.
0
The operation of my invention is briefly as follows
The crushing tank is by means of the water supply pipe kept filled with water
up to a point where the latter can run over the lower portion n of the edge of the
dam N, but not over the rest of said edge.
The chalk stone is thrown into the tank and falling to the bottom thereof is
crushed upon the bed B by the crushing wheel or roller F2 rolling over it. As
such wheel or roller travels around within the tank driven by the bar F and
revolving upright shaft D, it not only crushes and pulverizes the material on the
bed, but, by stirring up the water causes the fine particles or powder produced, to
be mixed with the water, so as to be in suspension therein.
As more water is run into the tank through the supply pipe, a portion of the
upper part of the body of water already in the tank, which part usually holds in
suspension the finest particles of material, flows over the lower part n, of the dam
edge to and through the screen 0 and outlet K, from which it passes to the
settling tanks or receptacles.
Other portions of the water containing the crushed material in suspension also
enter the space within the casing forming the dam through the openings n', n¹.
The coarser particles, resulting from the crushing action of the roller, which

page_text: may be carried upward by the disturbance of the water with which they are
mixed and which, in the machines as heretofore made and used with the open outlet,
would get out through the latter, as indicated hereinbefore, are caught and held
back by the screen.
The brush driven by the vibrating arm over the inner face of the screen keeps
the openings in the latter clear and unclogged by the particles too coarse to pass
through them.
As they are removed from the screen by the brush such particles tend to work
down through the openings n', n'. back into the body of the crushing tank again.
As only the finer particles flow out through the screen with the water and reach
the settling tanks, obviously none of the latter will, as heretofore, be needed to
receive the portions of material, which are too coarse to form part of the desired
fine grades of product.
There will then be necessary only so many settling tanks, as there are grades of
the fine marketable product to be separated from each other.
By my machine or apparatus, constructed and operating as described, I can
produce a more even and better quantity of the finest grades of whiting, and a
greater quantity of the finest grades from a given quantity.
The saving of time and labor and, consequently, in expense, secured by keeping
the coarse particles within the crushing tank, and doing away with the use of the
settling tanks heretofore employed for separating the too coarse from the fine
material coming with the water from the crushing tank, has been found to be
great.
While I have described the crushing tank as supplied with water, I do not
intend to limit myself to the use of such liquid, but contemplate, where desired,
using any other one which may be better suited to any particular material upon
which my mill may be used.
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 :-
1. In a mill, in combination with a tank containing liquid, and the crushing
mechanism working therein, a chamber communicating with the body of the tank,
so that liquid can flow into it from the latter, the outlet opening only reached by
the liquid after it has passed through the chamber, and a screen across the outlet,
substantially as and for the purpose described.
2. In a mill, in combination with a tank containing liquid and the crushing
mechanism working therein, means for supplying the liquid to the tank, an outlet
from the latter, a screen across the outlet, and a dam separating the outlet from
the body of the tank, having an inlet through which liquid from the upper part
of the tank can flow over the dam on its way to the outlet, substantially as and for
the purpose shown.
3. In a mill, in combination with a tank containing liquid and the crushing
mechanism working therein, means for supplying the liquid to the tank, an outlet
from the latter, a screen across the outlet, the dam having a portion of its upper
edge made lower than the rest to allow the flow of liquid from the upper part of
the tank to the outlet, a brush to engage the inner face of the screen, and means
for moving it back and forth over such face, substantially as and for the purpose
described.
4. In a mill, in combination with the tank containing liquid and the crushing
mechanism working therein, means for supplying the liquid to the tank, an outlet
from the latter, a screen across the outlet, and the dam consisting of a casing with
open top covering that part of the tank side in which the outlet is situated, having
in its bottom apertures to place its interior in communication with the body of the
crushing tank, substantially as and for the purpose specified.
5. In a mill, in combination with the tank containing a body of liquid and
crushing mechanism working therein, means for supplying the liquid to the tank,

page_text: an outlet from the latter, a screen across the outlet, the dam consisting of a casing
with open top covering the part of the tank side in which the outlet is situated,
and having an inlet through which liquid from the upper part of the liquid body in
the tank can flow, and openings in its bottom, a screen clearing brush within the
casing, a movable arm carrying brush and means for moving it to carry the
brush over the inner face of the screen, substantially as and for the purpose
specified.
6. In a mill, in combination with the tank containing liquid and the crushing
mechanism working therein, means for supplying the liquid to the tank, an outlet
from the latter, a screen across the outlet, the dam consisting of a casing with open
top dividing the outlet from the rest of the tank interior, and having an inlet for
the liquid from the tank, the swinging arm, the guide engaging the latter, the
screen clearing brush on the arm, the rotary shaft having a crank arm, a link
connecting the latter with the brush arm, and suitable gearing to drive the shaft,
as the crushing mechanism is operated, substantially as and for the purpose
described.
Dated this 30th day of November 1892.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.