by Currents or Signals in Electric Telegraph Apparatus.
Year: 1885

page_text: by Currents or Signals in Electric Telegraph Apparatus.
I, JAMES SCOTLAND, of the Anglo American Telegraph Company, St Pierre,
Miquelon, Electrician, do hereby declare the nature of my said invention for
IMPROVEMENTS IN COMBINED MAGNETS AND COILS TO BE ACTED ON BY CURRENTS
OR SIGNALS IN ELECTRIC TELEGRAPH APPARATUS," to be as follows, that is to
"
say :-
My said Invention has for its object to obtain increased sensitiveness, quickness
of action, and distinctness in the reception of currents or signals through electric
telegraph conductors; and my improvements are very advantageously applicable
with long lines such as submarine cables.
In carrying out my Invention I arrange the magnet or combination of magnets,
which may be either electro or permanent magnets, so as to have an annular field
of force in which the lines of force are in directions which are radial or in other
words across the annular space. The coil which forms part of the telegraphic
conductor is made in an annular form and is supported so that when no current is
passing through it, it is partly within the annular magnetic field the lines of force
of which cross its coils at right angles. With this improved arrangement a given
current through the coil will produce a movement of the coil in a quicker, stronger,
and more distinct manner than with ordinary arrangements, the action between
the current in the coil and the magnetic forces being more completely effective,
without the action of one part of the field interfering with that of another part.
The magnets may be arranged in various ways for the purpose in view.
In one
modification with electro magnets three soft-iron cores in their exciting coils are
arranged in a row side by side with the poles of the middle one reversed as regards
the other two. One end of the middle core projects to form the centre pole of the
annular field, and the same ends of the two outer cores have fixed to them a pole
piece formed with an annular middle part which surrounds the centre pole, the
narrow space between the inside of such middle part and the centre pole forming
the desired annular magnetic field. The other ends of the three cores are connected
by an iron bar. This combined electro magnet is by preference placed with its
cores horizontal, as this arrangement admits of the coil being delicately supported
by being suspended from adjustable points at some distance above the magnets, and

page_text: in a vertical plane coincident or nearly so with the outer faces of the pole pieces.
With this arrangement the coil will tend to hang about half in and half out
of the field in the annular space between the pole pieces and it will move further
out or in when a current or signal passes through it. The movement of the coil
may be utilised by means of a siphon recorder or in any other known way, as for
example in working as a relay.
A permanent magnet for the purposes of my Invention may consist of a central
bar or core of steel and a cylindrical shell of steel the two being united by a soft
iron disk at one end, whilst the annular space between them at the other end forms
the magnetic field in which the coil is partly immersed. I however prefer to build
up the magnet with separate bars or rods which can be more easily and completely
magnetised. A number of the bars or rods are combined to form the core and the
others are arranged in an outer cylindrical form, being connected to the core at one
end by a soft-iron disk and being fixed to a soft-iron ring at the other end, the field
being constituted by the annular space between this ring and the core.
1007

page_text: by Currents or Signals in Electric Telegraph Apparatus.
I, JAMES SCOTLAND, of the Anglo American Telegraph Company, St Pierre,
Miquelon, Electrician, 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, that is to say:
My said Invention has for its object to obtain increased sensitiveness, quickness.
of action, and distinctness in the reception of currents or signals through electric
telegraph conductors; and my improvements are very advantageously applicable
with long lines such as submarine cables.
In carrying out my Invention I arrange the magnet or combination of magnets,
which may be either electro or permanent magnets, so as to have an annular field
of force in which the lines of force are in directions which are radial or in other
words across the annular space. The coil which forms part of the telegraphic
conductor is made in an annular form and is supported so that when no current is
passing through it, it is partly within the annular magnetic field the lines of force
of which cross its coils at right angles. With this improved arrangement a given
current through the coil will produce a movement of the coil in a quicker, stronger,
and more distinct manner than with ordinary arrangements, the action between
the current in the coil and the magnetic forces being more completely effective,
without the action of one part of the field interfering with that of another part.
On the accompanying sheet of explanatory drawings one example of apparatus
made in accordance with my Invention is shown in figures, 1, to 5, figures, 6, and 7,
sbowing modifications of certain parts. Figure, 1, is a sectional plan, figure, 2, a
sectional elevation, and figure, 3, a front elevation but without certain parts shown
in figure, 2. Figure, 4, is an elevation of the annular bobbin on which the
conductor coil is wound, and figure, 5, shows the magnet poles and annular field.
The magnets may be arranged in various ways for the purpose in view. In
the modification with electro magnets shown in figures, 1, to 5, three soft-iron
cores, 11, 12, 13, in their exciting coils, 14, 15, 16, are arranged in a row side by
side with the poles of the middle one reversed as regards the other two. One end
of the middle core, 12, projects to form the centre pole of the annular field, and the
same ends of the two outer cores, 11, 13, have fixed to them a pole piece, 17, formed
with an annular middle part, 18, which surrounds the centre pole, 12, the narrow
space between the inside of such middle part and the centre pole forming the
desired annular magnetic field in which the lines of force are radial, as shown in
figure, 5. The other ends of the three cores are connected by an iron bar, 19.
This combined electro magnet is by preference placed with its cores horizontal as
this arrangement admits of the coil, 20, being delicately supported by being
suspended from adjustable points at some distance above the magnets, and in a
vertical plane coincident or nearly so with the outer faces of the pole pieces, 12, 18.
The conducting coil, 20, is wound on an annular bobbin, 21, shown separately in
figure, 4, and is suspended by means of two wires, 22, the lower ends of which are
attached to the outer face of the bobbin, 21. The upper ends of the suspending

page_text: wires, 22, are attached to a nonconducting crossbar, 23, fixed to a pillar, 24, which
is itself fixed to the top of the annular pole piece, 18. The pillar, 24, has a second
nonconducting crossbar, 25, fixed to it, and in this crossbar are fixed the terminal
screws, 26, for the conducting wires, these screws being connected by wires to the
suspending wires, 22, which are themselves connected to the two ends of the
coil, 20. The upper part of the pillar, 24, is stiffly hinged to the lower part to
allow of adjustment of the position of the crossbar, 23, from which the coil, 20, is
suspended. When the parts are properly adjusted the coil, 20, should tend to hang
about half in and half out of the field in the annular space between the middle
core, 12, and the annular pole piece, 18, and it will move further out or in when a
current or signal passes through it. The movement of the coil, 20, may be utilised
by means of a siphon recorder, or in any other known way, as for example, in
working as a relay. In figure, 2, my improved apparatus is shown as connected to
a siphon recorder, a small rod or wire, 27, fixed to the coil bobbin, 21, being
connected by a thread or fine wire, 28, to the pen, 29, of the recorder.
A permanent magnet for the purposes of my Invention may consist, as shown in
section in figure, 6, of a central bar or core, 31, of steel, and a cylindrical shell, 32,
of steel, the two being united by a soft-iron disk, 33, at one end, whilst the
annular space between them at the other end forms the magnetic field in which
the coil (20) is to be partly immersed. I however prefer to build up the magnet
with separate bars or rods, as shown in end view on figure, 7, as such bars or rods
can be more easily and completely magnetised. A number of the bars or rods are
combined to form the core, 34, and the others are arranged in the form of an outer
cylinder, 35, being connected to the core, 34, at one end by a soft-iron disk; and
being fixed at the other end to a soft-iron ring (not shown in figure, 7,) the field
'being constituted by the annular space between this ring and the core, 34.
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
•
Arranging and suspending a coil through which currents or signals are passed in
electric telegraph apparatus, in an annular field crossed radially by lines of force
due to suitably arranged magnets, substantially in the manner and for the purposes
hereinbefore described.