Improvements in Magnetic Separators.
Year: 1896

page_text: Date of Application, 1st Dec., 1896-Accepted, 20th Feb., 1897
[Communicated from abroad by JOSEPH BEALS HAMILTON, of Hebron Street,
Springfield, Massachusetts, U.S.A., Manufacturer.]
Improvements in Magnetic Separators.
I, VICTOR ISIDORE FEENY of 60 Queen Victoria Street, in the City and
County of London, Chartered Patent Agent, 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:-
My invention relates to that class of devices for magnetically separating particles
of iron from a mass of loose material in which the operating means consists of an
electro-magnetic roll or cylinder, and it has especial reference to devices of this
class as applied to the removal of iron particles from the semi-liquid pulp from
which paper is inade.
The objects of the invention are to provide an apparatus of this nature which
will be of a simple and comparatively inexpensive construction; in which the
revolving roll or cylinder will have a very powerful magnetic attraction; in which
the roll or cylinder will be constantly cleaned by automatic means; and in which
the particles of iron removed from the roll by the automatic cleaning mechanism
will be automatically removed from the latter and prevented from re-entering
the pulp.
To these ends, my invention consists in the magnetic separator constructed and
operating as hereinafter fully described and particularly pointed out in the claims.
Referring to the drawings, in which like letters and numerals designate like
parts in the several figures,
Figure 1 is a side view of an apparatus embodying the invention and a partial
cross-section of the trough or chute in which it is located.
Figure 2 is an end view thereof, looking toward the right in Figure 1.
Figure 3 is a partial longitudinal section of the roll.
Figure 4 is a cross-section thereof.
Figure 5 is a view in perspective and drawn to a larger scale of one of the
spraying boxes in which the roll wiper is cleaned at each end of its traverse.
Figure 6 is a cross-section of the wiper.
The letter A designates a trough or chute for conducting a flowing material, as
for example the "sand trap" through which pulp passes on its way to a paper-
making machine, and at some convenient point in which the apparatus devised by
me is located. The letter B designates the electro-magnetic roll, which has a
centrally disposed longitudinal core 2 and four radially disposed wings 3 preferably
cast therewith, upon which wings are wound the four helices 4 of wire extending
longitudinally of the roll and nearly to each of its ends. I prefer to wind said
four helices from a continuous wire, with the direction of the wind reversed upon
each alternate wing, but do not restrict myself thereto. In its preferred form the
shell of said roll will be slotted from end to end, between each of the wings 3, the
walls of said slots being made slightly diverging outwardly, and, after the helices
are wound, said slots will be filled with strips 5 of brass or other non-conducting
material, as shown in Figure 4, said strips having their sides beveled as shown and
being securely retained in position by plates 6 near each end of the roll, which
span the slots upon the inner side of the shell and are connected to the strips by

page_text: screws 7. By thus dividing the circumference of the roll-into four equal parts,
with non-conducting divisions between them, I form four magnetic poles adjacent to
said strips and equalize the powerful. magnetic attraction of the roll about its
circumferential surface in such manner as to practically obviate any neutral points
thereon. Heads 8, are secured to the ends of the roll, with suitable interposed
packing to prevent entrance of moisture to the helices, and said heads are provided
with trunnions 9 10 which have their bearing in the sides of the trough A, suitable
stuffing-boxes 12 being provided to prevent the escape of the liquid material from
the latter. The trunnion 10 is of tubular form to receive the ends of the wire.
forming the helices, which ends are connected respectively to disks 13 14 on said
trunnion near its outer end, as shown in Figure 3, the extreme outer end of the
trunnion being plugged as shown. The wires 15 16 from the electrical generator
are connected to binding posts 17 18 on the side of the trough, and brushes 19 20
extending from said binding posts to the disks 13 14 respectively serve to conduct
the current to and from the ends of the wire forming the helices within the roll in
a manner which will be obvious from an inspection of the, drawings. A band-
pulley 21 carried by the trunnion 9 of the roll enables the latter to be driven by
belt from a suitably disposed counter-shaft. The trough A is preferably provided
with a transverse depression in its bottom, which is concentric to the roll as
indicated by broken lines in Figure 2, and as the pulp or other material flows
beneath, the roll every iron particle contained therein is infallibly brought within
the powerful magnetic field of the roll and is attracted to and retained upon the
same until removed by the wiper presently to be described. A packing of felt or
other suitable material is preferably interposed between the en is of the roll and
the adjacent walls of the trough, as shown at 22, to prevent the passage of the
flowing material at such points and compel it to pass beneath. the roll. The means
for, automatically cleaning the roll, are as follows The letter C designates a
screw-shaft journalled at its ends, in ,brackets 23 on the trough, said shaft being
parallel with and lying in the vertical plane of the axis of the roll. Upon said,
shaft is cut a double reversed thread, and at one end it carries a pinion 24 which
meshes with a gear 25 on the trunnion 9 of the roll, whereby an accelerated motion
is transmitted to the shaft from the roll. The letter D designates the wiper, which
is composed of a block 26 of inverted T-shape, having a hole 27 therein to receive
the shaft C, and a frame 28 which loosely embraces the sides, of said block and is
provided with two studs 29 which pass upwardly through holes in the block in such
manner as to afford to the frame a limited vertical movement upon the latter while
pins 30 inserted in the upper ends of said studs prevent the frame from dropping
entirely away from the block. At its upper end said frame, is provided with the
oppositely projecting flanges 31 which are adapted to be engaged by inwardly
projecting guide-bars 32.on the brackets 23 as the wiper approaches the end of its
movement in either direction, to afford vertical support to the frame and keep its
under side in horizontal alignment with the surface of the roll., To the opposite
sides of the frame are secured, by means of bearing plates 33 and screws 34, strips
of felt 35 or other suitable material adapted to exert a wiping -action upon the
surface of the roll and the lower edges of which are beveled to conform substantially
to the curvature of the surface of the roll. To the under side of said frame,
between the strips 35, is secured a piece of iron or steel 36, which by responding
to the magnetic attraction of the roll causes the wiping strips to bear with con-
siderable pressure upon the latter to ensure the thorough cleaning of the same.
The block 26 is provided with a small hole extending from the hole 27 to ite upper
end, which is tapped near its outer end, and within said small hole is located the
shank 37 of a dog 38 which operatively engages the thread of the screw-shaft, a
set-screw 39 at the outer end of said hole preventing upward movement of said
dog while permitting it to have the, slight rocking movement necessary to enable
it to follow the reversed thread of the shaft.
The action of the screw-shaft upon the wiper causes it to travel back and forth,
from end to end of said shaft, thereby causing the strips 35 to remove from the

page_text: surface of roll B all particles of iron lodged thereon, and to prevent said particles.
from again entering the material flowing through the trough I effect a washing
action of the wiper at one or both ends of its movement, preferably the latter, and
for this purpose I locate spray boxes E E upon the trough beneath the ends of the
screw-shaft. Said boxes, one of which is shown enlarged in Figure 5, are open at
the top and are provided with a recess 40 in their inner side wall, through.
which the lower portion of the wiper passes in entering and leaving the box. At
each end of the box is located a perforated pipe 41 to which water is preferably
supplied as follows:-A supply pipe 42 leading from any source of water under
moderate pressure extends heneath the trough A, and from said pipe extend the
pipes 43 leading to the pipes 41 at one end of the boxes E, while branch pipes 44
lead from said pipes 43 to the pipes 41 at the opposite ends of said boxes." The
water thus supplied to the pipes 41 issues therefrom in a series of jets which engage
the wiper from opposite directions as the latter is carried into and out of the box,.
in such manner as to wash therefrom all particles of iron and accumulations of pulp
located thereon, which latter fall to the bottom of the box and thence escape
'through waste-pipes. 45 leading from the boxes and are thus prevented from.
re-entering the flowing material.
The operation of the apparatus thus constructed is as follows:-The roll B being
so connected with a power shaft as to cause a slow revolving movement thereof, in
a direction opposite to that of the movement of the flowing material, and the
electrical connections between said roll and a generator being established as
described, every iron particle contained in said material will be attracted to and
retained upon the roll.
By its described connection with the roll trunnion, the screw-shaft C is given a
considerably accelerated motion which carries wiper D back and forth in such
manner as to cause it to wipe from the roll the iron lodged thereon. While the
wiper is over the roll its frame 28 is drawn toward the latter by the magnetic action
of the metallic piece 36 so as to secure a thorough wiping of the roll by the strips 35.
As the wiper is about to pass beyond the end of the roll at either end of its
traverse, the flanges. 31 on frame 28 are carried upon the guide-bars 32 of
brackets 23, by which the wiper is steadied in its further movement and is truly
guided upon the end of the roll in its return movement. As soon as the wiper
leaves either end of the roll it enters one of the spray boxes E and the strips 35.
are thoroughly washed by the jets of water from the pipes 41, to remove the iron
therefrom.
It will be obvious that the automatic cleaning mechanism devised by me is
adapted for use in connection with any form of electro-magnetic roll or cylinder,
and I do not wish to restrict its use to the particular form of roll herein shown and
described.
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 a magnetic separator, the combination with an electro-magnetic roll or
cylinder, of a wiper adapted to be held in contact with said roll or cylinder by
magnetic attraction, and means for imparting movement to said wiper longitudinally
of the roll or cylinder, substantially as set forth.
2. In a magnetic separator, the combination with an electro-magnetic roll and
means for revolving the same, of a wiper adapted to engage said roll, means for
imparting to said wiper a reciprocatory movement longitudinally of the roll, and
means for automatically cleaning said wiper at one end of its traverse
substantially as set forth."
3. In a magnetic separator, the combination with an electro-magnetic roll, of a
wiper bearing against said roll, means for imparting to said wiper a reciprocatory
movement longitudinally of the roll, and means for directing a jet of water against
the wiper, at one end of its traverse, substantially as set forth.

page_text: 4. In a magnetic separator, an electro-magnetic roll comprising a hollow shell, a
centrally disposed core, and radial wings joining said core to the shell, about which
wings are wound belices of wire, means for conducting an electrical current to and
from the helices in said roll, a wiper bearing against the surface of said roll, and
means for moving said wiper longitudinally of the roll, substantially as set forth.
5. In a magnetic separator, the combination with an electro-magnetic roll, of a
wiper bearing against said roll, a screw-shaft operatively engaging said wiper and
adapted to move it longitudinally of the roll and beyond the end of the latter, and
a spray box located adjacent to the end of the roll and containing water jet devices
as described, into which box said wiper is carried by its operating shaft when it
leaves the roll, substantially as described.
Dated the First day of December 1896.