Year: 1886

page_text: I, EDWIN PACKARD, of Grosvenor Street, in the County of Middlesex, Gentleman,
do hereby declare the nature of this invention (a communication to me from abroad
by Edwin C. Griffin, of New York, United States of America) and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement, and accompanying drawing, (that is to say) :-
This invention relates to that class of mills, in which the reduction or pulveriza-
tion of ores and other substances is accomplished by the revolution of one or more
rollers within and against the inner wall of a ring or die, the said rollers being
held in contact with the ring or die by centrifugal force.
The object of the invention is to produce a mill in which ores and other sub-
stances, however refractory, and of whatever degree of hardness may be rapidly
and cheaply pulverized and reduced to an impalpable powder.
Attempts have been made to accomplish the same results, but so far with only
partial success, their failure having been due mainly to the defective means used
to secure the desired ends, resulting in great loss of power and excessive wear of
the mills.
In the present invention the difficulties heretofore experienced in the particulars
named are overcome, and the easy and ready adjustment of the parts by which
the work is performed is effected, so that a mill is obtained which not only per-
forms its work rapidly and cheaply, but is readily understood, easily managed and
comparatively inexpensive in its manufacture.
The essential feature of the invention consists in the means and mechanism
employed by which the pulverizing rollers are held in position and caused to
rotate against the inner wall of the die or ring by centrifugal force without supports
from above or below.
By doing away with such supports and causing the rollers to support themselves
in place with only slight guidance and control, while at the same time accom-

page_text: plishing the same or better results in pulverizing than have been secured in other
mills, the excessive wear in the mills is prevented and at the same time the power
heretofore lost therein, is to a large extent saved.
The accompanying drawings illustrate the form of mill with its parts which
I prefer to use, as well as some modifications thereof, but I do not limit myself to
the precise forms there shewn as it is evident that other modifications of the mill
and of the parts may be made without departing from the nature and character of
the invention.
In the drawings, figure 1 represents a side elevation of the mill with a portion
of the pan, cover, and die broken away, showing the rollers in operative position,
and the semi-circular pockets in the carrier having inclined bottoms.
Figure 2 is a plan view of the mill with a portion of the cover removed, showing
a partial plan view of the interior of the mill, the arrangement of the die or ring,
the rollers, the adjustable swinging arms on which the rollers revolve, and the die,
links, and feed plates.
Figure 3, is a vertical section, through the centre of the mill.
Figure 4, is a broken plan view of the mill with the cover removed shewing
a modification of the means for sustaining the rollers, of which Figure 5 is a partial
elevation.
In the drawings p represents the circular shell or casing enclosing the die or
ring and the operative mechanism, having openings o, o³ in the bottom near the
centre for the admission of air.
Within this the circular die d is placed, of such diameter as to be readily secured
in place by the packing f.
This die rests upon pads e³, of wood, rubber or other suitable elastic material
placed within the casing as shewn.
A ring h, bolted to the top of the pan p, secures the die d in its place, the space
between it and the die being packed with some elastic material. Direct contact
between the pan and die is thus prevented, and the objectionable jarring and noise
incidental to this class of mills are greatly reduced.
The mill is provided with a cover j, having an exhaust pipe c, opening into it on
the top, and into this pipe opens a pipe g, closed by a swinging door g³, so as to
prevent the escape of dust into the hopper.
Through the centre of the pan p, revolves a shaft l, driven by any suitable
power connection To the top of the shaft l, a rotating carrier b is rigidly
secured.
This carrier is provided with semi-circular pockets 62, in which the rollers r, r,
freely rotate.
The bottom of the pockets are inclined as shewn at y, and may be cast integral
with the carrier or be bolted thereto.
An open space or mouth is provided at the lower edge of each bottom thus per-
mitting the ore or other material being pulverized to be caught on the said bottom
and scooped or carried up to the rollers again, by the revolution of the carrier.
Swinging arms t, t, having rollers journaled in the heads thereof are secured to
the carrier at m, m. The arms t, t, have hollow heads t¹, t¹, and downwardly pro-
jecting sleeves therefrom to receive the spindle a³, and the surrounding core t²,
(see left hand part, figure 3). The heads of the arms t, t, are secured to the lugs b³,
of the centre of the carrier b, by adjustable links v, v.
Each spindle a³, is rigidly secured in the head t¹, by a set screw a³. Surrounding
the lower end of each spindle a², is a hollow core t². This core t³, fits loosely over
the said spindle a², and may be easily removed therefrom, the core revolving
thereon. To this core t2, is rigidly secured a roller r, which rotates in the pocket b²,
formed in the periphery of the carrier b, and against the inner wall of the die or
ring d. In the heads of the arms t, t, oil cups 8, 8, are formed having suitable caps
secured by set screws.
An aperture a, is bored part down the upper end of each spindle a³, from which
aperture openings extend to its sides, so that by putting oil in the oups 8, 8, the

page_text: parts are readily lubricated. It will thus be seen that the rollers r, r, may rotate
freely in the pockets 62, formed in the periphery of the carrier b, and against the
inner wall of the die d, when the said carrier b, is revolved. The said rollers
being loosely secured to the spindles a², by the cores t², may, when in operation
have a vertical movement sufficient to bring their peripheries against the entire
depth of the wall of the die or ring d. The arms t, t, are loosely secured to the
carrier b, so that they may swing out and in, and up and down, as the rollers 7, r,
are carried out and in and up and down by the centrifugal force imparted from
the revolution of the carrier b. The heads t¹¹ of the arms t, t, may be so adjusted
by the links v, v, that when in operation the axes of the rollers r, r, and their
spindles a, a, will correspond with the central axis of the carrier b around which
they revolve. In this way all the friction of the parts is overcome as there is no
binding, the rollers moving freely on their spindles and against the die, being
supported in their position by centrifugal force alone. When the mill is not in
operation the rollers r, r, fall down out of contact with the wall of the die d, and
the projecting ends of the cores t³, rest upon the inclined bottoms y, of the
pockets 6³.
On the right hand side of figure 3, is shown another way of securing and
arranging the spindle in the head of the arm and of securing the rollers r, r, to the
said spindles.
In this case the rollers r, r, are rigidly secured to the spindle a² and the spindles
rotate in the apertures or bores formed in the heads of the arms.
In figure 5 is shewn another way of securing the rollers r, r, to the swinging
arms. In this case each spindle is rigidly secured at its opposite ends to the said
arm which is in two parts, and the roller rotates upon such spindle.
The operation of this mill in dry grinding is as follows:
The carrier and feed distributor b, throws the material dropped upon it from the
feed pipe g, outwardly between the pockets b³, upon and against the inner die d,
where the rollers r, r, crush it by centrifugal impact. As fast as the material is
thoroughly pulverized, it is carried up and out of the exhaust pipe c, by the current
of air produced by the revolving of the carrier b, or by an exhaust fan connected
with the said pipe c. The material remaining unpulverized, falls down into the
pan, is caught up by the inclined bottoms y, y, of the pockets b³, and again forced
between the rollers and the die with the incoming material, until it is pulverized
and carried off as above described.
For wet grinding, screens, not shewn in the drawing, are put into the cover j,
just above the ring h, and the openings o, o³, for the ingress of air are closed by
any suitable means, the water being introduced with the material or in any other
suitable manner.
In this case the water and fully pulverized material pass out through the screens
and are carried off to a receptacle by a trough or any other suitable conveyor.
The fineness of the material will be determined by the strength of the current
of air, or the mesh of the screen, or both, as the case may be.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1. In an ore pulverizer, the combination of a circular die, a carrier mounted
within the same and formed with semi-circular pockets in the periphery, arms
secured to the said carrier, and rollers fitting and rotating in said pockets and
against the inner wall of the said die by centrifugal force, substantially as
described.
2. In an ore pulverizer, the combination of a circular die, a carrier mounted
within the same, adjustable guiding arms secured to the said carrier and having
spindles projecting from the free ends thereof, and rollers journaled on the said
spindles, carrying the said guiding arms, and rotating against the said die by
centrifugal force, substantially as described.

page_text: 3. In an ore pulverizer, the combination of a circular die, a disc carrier mounted
within the same and having semi-circular pockets in the periphery provided with
inclined bottoms open at their lower edges and forming scoops, adjustable guiding
arms secured to the said carrier at both ends and having spindles projecting from
the loose ends, and rollers journaled on the said spindles carrying the said guiding
arms and rotating against the die by centrifugal force, substantially as described.
4. In an ore pulverizer, the combination of an enclosing shell provided with
a hopper and an exhaust pipe and enclosing a circular die, a disc carrier, adjustable
arms. secured to the said carrier, rollers journaled on the said arms and rotating
against the said die by centrifugal force, and an operating shaft, substantially as
described.
5. In an ore pulverizer, the combination of an arm having a hollow head in the
form of a downwardly projecting hood, a spindle secured to the said head, a hollow
core, and a roller, constructed and arranged substantially as described.
Dated this 15th day of October 1886.
EDWARDS & Co.,
Agents for the Patentee,
35, Southampton Buildings, London.