Improvements in Electro-magnetio Separators.
Year: 1895

page_text: Date of Application, 14th Aug., 1895
Complete Specification Left, 14th May, 1896-Accepted, 20th June, 1896
PROVISIONAL SPECIFICATION.
Improvements in Electro-magnetio Separators.
I, FREDERICK GEORGE ROBINSON, of 9, Strand Street, Liverpool, Electrical
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in electro-magnetically operated
apparatus for separating or withdrawing particles or pieces of iron and steel
from material to which they are foreign, such as grain, flour, meal and other
like or pulverulent material, in the course of their manufacture.
An electro-magnetic separator according to this invention comprises an endless
travelling band of iron or steel mounted on rollers carried by an inclined frame-
work or shoot. One of such rollers, i.e., the one at the top of the incline, forms a
revolving magnet, its periphery being in four sections, each section being supported
by, say, two electro-magnets, the cores of which are permanent magnets and form
the spokes of the roller. Each section of the roller periphery therefore forms a
pole, or armature, of the magnet or magnets which support it.
Such roller
preferably forms the driving roller of the endless band, being provided with the
usual drum and belt or other gearing. Between the end rollers of the travelling
band are disposed fixed electro-magnets, the cores of which are permanent magnets
and provided with anti-friction rollers, upon which the upper portion of the endless
band travels. The coils of the revolving magnets and of the fixed magnets may
form one circuit and may be so arranged that the peripheral poles of the revolving
magnet and the poles of the fixed magnets which carry the anti-friction rollers, are
of like magnetism; or such magnets may be arranged in pairs-adjacent poles
being of different magnetism.
The grain, flour, meal, or other material containing pieces or particles of iron or
steel, is fed from a shoot onto the travelling band at the upper end of the incline
and falls by gravitation down the inclined surface of the band, the band being
arranged to travel upwards or in the reverse direction to the grain. Any iron or
steel which may be in the grain is attracted and held against the band by the
magnets underneath it, and is carried upward and over the upper or magnetic
roller. As the under or returning portion of the band leaves the magnetic field of
such roller the pieces of iron or steel which have been collected, detach themselves
and fall into a receptacle provided for them.
: Suitable means for tightening the band are provided and may consist of
a guide roller mounted in a frame capable of being extended underneath the
separator.
:
In electro-magnetic separating apparatus at present in use the attracting
magnets are usually energised by a dynamo which is driven by the machinery of
the mill or other place in which the separator is employed, and such apparatus is
open to the objection. that when the mill machinery stops, the magnets become
demagnetised and the iron or steel which they hold are again liberated into the
grain or other material. By the use of permanent magnets as the cores of such
attracting magnets such liberation will not occur, as the permanent magnetism of
the cores will be sufficient to hold the iron particles in suspension until the.
machinery and dynamo are again started.
I
1005

page_text: improvements in Electro-magnetic Separators.
I, FREDERICK GEORGE ROBINSON, of 9, Strand Street, Liverpool, Electrical
Engineer, do hereby declare the nature of the said invention and in what manner
the same is to 'be performed to be particularly described and ascertained in and by
the following staternent :-
This invention relates to improvements in electro-magnetically operated
apparatus for separating or withdrawing particles or pieces of iron and steel
from material to which they are foreign, such as grain, flour, meal, bones,
china-clay, and other like or pulverulent material, in the course of their
manufacture.
An electro-magnetic separator according to this invention is illustrated in the
accompanying drawing, in which
Fig. 1 is a sectional elevation, Figure 2 an end view partly in section, and
Fig. 3 a plan, of the same.
Fig. 4 is a cross section of the separator, and
Fig. 5 is a diagram of electric leads.
The separator comprises an endless travelling and magnetisable band A,
mounted on rollers B, B', carried by an inclined frame C. The roller B at the
top of the incline forms a revolving magnet, its periphery being in four
sections bb bb, each section being supported by an electro-magnet the core 6' of
which is a permanent magnet, such cores 6' forming the spokes of the roller.
Each section of the roller periphery therefore forms a pole-piece to the magnet bl
which supports it. The roller B forms the driving roller of the endless band A,
its journal being provided with a belt-pulley D. Between the rollers B, B1, the
travelling band A is supported upon fixed electro-magnets, the cores E of which
are permanent magnets provided with anti-friction rollers e, upon which the upper
portion of the endless band A travels. The magnets E are mounted on a pole-
piece e common to all. The tension of the band A is regulated by the roller B'
carried in adjustable bearings F.
Grain, flour, meal, china-clay "slip," or other material containing fragments or
pieces of iron or steel, is fed from the shoot G onto the travelling band A at the
upper end of the incline C, and falls by gravitation down the inclined surface of
the band A, which is arranged to travel against the direction of the falling
material. Any iron or steel which may be in the material is attracted and held
against the band A by the magnets E underneath it, and is carried upward and over.
the magnetic roller B. As the under or returning portion of the band A leaves
the magnetic field of such roller B the pieces of iron and steel, which have
been collected, detach themselves and fall into a receptacle placed to receive
them.
"
Ledges C¹ prevent material finding its way below the travelling band A; and
where liquid material such as china-clay "slip or slurry, or the like, is being
treated, these ledges may be lined with india-rubber to form a water-tight
joint.
H, H', are the electrical terminals of the separator. The arrangement of leads
may be as illustrated in the diagram, Fig. 5. Entering at H the current passes to
a brush a bearing upon a metallic collar a' mounted on an insulating sleeve on the
journal of the roller B. From the collar a¹ the current passes, by an insulated
lead, through the coils of the magnets 6' in series, from which it is led, by an
insulated lead, to a similar collar as on the roller journal, and brush a. From a
the current passes through the coils of the fixed magnets E, which are divided in
two groups and arranged in parallel. Passing from the coils of the magnets E the
current leaves the separator by the terminal H³. The coils of the revolving

page_text: magnets and of the fixed magnets E thus form one circuit, the peripheral poles.
of the magnets 61, and the poles of the fixed magnets E which carry the anti-
friction rollers e, being of like polarity. It must however be understood that the
magnets of the separator may be so wound that adjacent poles are of opposite
polarity, and in place of single bar magnets there may be substituted two or more
magnets, or horseshoe magnets.
In electro-magnetic separating apparatus at present in use, the attracting
magnets are usually energised by a dynamo which is driven by the machinery of
the mill or other works in which the separator is employed, and such apparatus is
open to the objection that when the mill machinery stops, the magnets become
demagnetised and the iron or steel which they hold is again liberated into the
material. By the use of permanent magnets as the cores of such attracting
magnets such liberation will not occur, as the permanent magnetism of the cores
will be sufficient to hold the iron particles in suspension until the machinery and
dynamo are again in motion.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. An electro-magnetic separator comprising an endless magnetisable band
arranged to travel on rollers, one of which is built in sectors, each sector forming
an electro-magnet whose core is a permanent magnet, said band being supported
between said rollers by fixed electro-magnets the cores of which are permanent
magnets; arranged and operating substantially as described.
2. An electro-magnetic separator comprising an endless magnetisable band
travelling on rollers in the reverse direction to the material being treated, one of
which rollers is built in sectors each sector forming an electro-magnet whose core
is a permanent magnet, said band being supported between said rollers by electro-
magnets whose cores are permanent magnets provided with anti-frictiou rollers, the
tension of such band being regulated by a roller carried in adjustable bearings ;
all in combination and operating substantially as and for the purpose herein set
forth.
3. In an electro-magnetic separator the combination with an endless magnetis-
able travelling band, of a roller the periphery of which is in sectors, each sector
being supported by an electro-magnet whose core is a permanent magnet, said
magnets being energised in or substantially in the manner herein set forth.
4. In an electro-magnetic separator the combination with an endless magnetisable
travelling band, of a series of fixed electro magnets whose cores are permanent
magnets adapted to support said band on anti-friction rollers, arranged and
operating substantially as herein set forth.
Dated this 13th day of May 1896.
J. A. COUBROUGH,
Registered Patent Agent,
10 St. George's Crescent, Liverpool, Agent for the Applicant.