IMPROVEMENTS IN ELECTRO MAGNETS.
Year: 1882

page_text: LETTERS PATENT to Virgil Warren Blanchard, of the city and state of New
York, United States of America, Doctor of. Medicine, for an Invention of
"IMPROVEMENTS IN ELECTRO MAGNETS.".
COMPLETE SPECIFICATION filed by the said Virgil Warren Blanchard at
the Office of the Commissioners of Patents on the 8th December 1882.
VIRGIL WARREN BLANCHARD, of the City and State of New York, United States
of America, Doctor of Medicine, "IMPROVEMENTS IN ELECTRO-MAGNETS"
.
The invention relates to improvements in "Electro Magnets" in the construction
and arrangements of which I use copper plates instead of the wire common for
that purpose, and by means of the hereinafter described system of connections and
insulation I am enabled to utilize fully the entire surface of the plates and to
readily and conveniently employ any desired portion of the magnetic force with
the most satisfactory results. In the accompanying drawings in which similar
letters indicate corresponding parts Figure 1 shows a portion of the magnet in
front elevation. Figure 2 is a sectional view through the body of the magnet on
line Y. Y. of Figure 1 Figures 34 and 6 are detail views of modes of connecting
the plates, and Figure 5 is a side elevation of the coupler. In the drawings
A represents my improved magnet which is constructed as follows. The core is
composed of a bundle of soft iron wires C forced tightly into a soft iron tube B
which is insulated from its environment by a layer of asbestos paper D or its
equivalent. Upon the core so constructed, or constructed of one piece of iron, I
place insulated disks of sheet copper which may be of any desired thickness, each
formed with a central aperture the size of the insulated core and having a slit
extending radially from the central aperture to the edge of the disk this slit is
formed with the cylindrical grooves & along the opposite edges, on opposite sides of
the sheet of metal, or if preferred the metal necessarily removed to form the slit
may be turned up to form a lip on one side of the slit or a number of pins may be
fixed to one edge of the slit instead of the turned up lip. To facilitate the use of
any desired length of magnet without altering their structure or position, a number

page_text: of the said copper plates are provided with lugs a³, by means of which and the
coupler F consisting of the strips of metal g g hinged at one end and provided
with a tightening screw g¹ at the other, any number of sections of one entire
magnet may be connected and put into or out of use. By making the couplers F,
of varying sizes the internal resistance of the magnet may be increased or
diminished in the portions to which they are applied. Between each two of the
metal disks A, is placed an insulating disk b, preferably of asbestos paper which
said insulating disks are similar in size and slitted as are the disks A. The copper
and paper disks alternate along the core and in order to distribute the weight of
pins or strips equally, the said connections are arranged in the form of a continuous
spiral from end to end of the completed magnet the object being to break the
joints and provide sufficient space between the joints of the plates for the insertion
of the pins or plugs el, in the grooves f, f¹, the plates being so placed on the core
that the groove on the upper side of one plate, the opening in the insulating disk,
and the groove in the lower side of the next copper plate will register. In case
the disk A has the lip e, formed at the edge of the slit, the lip will take the place
of the plugs and touch the under side of the upper copper disk, the insulating disk
being appropriately placed thereby forming the desired connection, and if desired
strips of insulating material may be inserted to fill the radial slits in the plates
when used without separate connecting pins. A current entering at either end of
a magnet constructed as described would be obliged to traverse the entire surface.
of each plate thus utilizing them to their fullest extent, and by thus arranging the
plates a magnet is produced in which the internal or essential resistance is reduced
to the minimum and in which all the parts are in exactly the same relation to the
core, which cannot be the case with continuously coiled wire. Having described
my invention what I claim and desire to secure by Letters Patent is, 1. An electro
magnet composed of alternating slitted disks of copper and insulating material.
arranged upon a core composed of soft iron wires enclosed within an insulated soft
iron tube said plates being continuously connected, substantially as described.
2. The centrally perforated radially slitted metal disks A formed with grooves or
depressions f, f', substantially as shown and described. 3. The disks A provided
with projecting ears a' in combination with the coupler F, insulating disks b, and
a magnetic core, substantially as shown and described. 4. The centrally apertured,
radially slitted insulating disks, in combination with metal disks A, and the core
of an electro magnet, substantially as described.
In witness whereof' I the said Virgil Warren Blanchard have hereunto set
my hand and seal this eighth day of December in the year of our Lord One
Thousand Eight Hundred and Eighty two.