Improvements in Appliances used for Regulating or Cutting Out an Electrical Circuit.
Year: 1890

page_text: Date of Application, 13th May, 1890
Complete Specification Left, 2nd Feb., 1891-Accepted, 14th Mar., 1891
PROVISIONAL SPECIFICATION.
Improvements in Appliances used for Regulating or Cutting Out an
Electrical Circuit.
FRANK BRYAN, 11, Brackley Terrace, Brackley Road, Chiswick, London, W.,
Electrician, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to produce an instrument which can be regulated
to make or break an electrical circuit at a prearranged point, and at the same time
form a cheap, reliable, and more or less incombustible article, and for this purpose
I make use of one or more mercury cups or receptacles which form terminii of wires
or the like, in connection with an electrical circuit, and in conjunction therewith a
coil of copper wire, preferably bare, or other convenient conducting material, so
mounted as to admit of complete or partial rotation around a given centre; or other
convenient movement, which shall cause the two ends of the said coil (which are
by preference brought in proximity to each other) to be taken away from or
inserted into the said mercury cups, or their equivalent as may be desired, or by
such motion, complete or break the main or any supplementary circuit or circuits,
or otherwise take out or place in extra resistance in any circuit or circuits.
Now this movement of the coil I produce by so arranging it, that it embraces
without contact a core of magnetic material, which is so formed as to admit of the
said rotation or other convenient movement of the said coil, and is itself capable of
regulation as regards the amount projecting within the said coil. In place of the
core above described, I may use a second coil or a tube of magnetic material either
projecting within or enveloping the said coil.
may use such counterweights or other equivalent adjusting devices as may be
deemed necessary, or replace mercury contacts with metal springs or other con-
venient contact making appliances.
I may also replace the core with a tube of copper or other convenient conducting
material, for use on alternating currents.
Instead of working direct I may employ supplementary triggers or springs, or
other convenient appliances, actuated by the movement of the said coil.
The coil may if necessary be shunted by a resistance arranged between the two
ends so that any given proportion may pass through the coil.
Altogether the instrument is simple, has a wide range of adjustment, and the coil
or its equivalent in some cases being bare, reduces risk of fire or break-down.
Dated this 13th day of May 1890.
FRANK BRYAN.
COMPLETE SPECIFICATION.
Improvements in Appliances used for Regulating or Cutting Out an
Electrical Circuit.
1, FRANK BRYAN, 11, Brackley Terrace, Chiswick, London, 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 a cheap, reliable and practically incombustible instru-
ment which can be adjusted to break an electrical circuit whenever the current
attains a predetermined strength, as I shall describe referring to the accompanying
drawing.
Fig. 1 is a front view, Fig. 2 is a plan and Fig. 3 is an end view of a cut out
instrument according to my invention.

page_text: M² M² are two cups containing mercury. M is fixed against a base plate B of
insulating material and is connected to one L' of the conductors for the circuit.
The cup M2 is quite separate from M¹ and forms part of a metal frame F
which is fixed to the base B and is connected to the other conductor L² of the
circuit.
The frame F has an eye E through which passes an iron bar C bent to a circular
curvature. This bar C can be fixed in the eye E by a set screw S so that a greater
or less length of it projects above and beyond the eye.
A coil of wire W, preferably bare copper wire, is carried by an arm A which
is pivotted to the frame F at P P, and the two ends of this wire coil dip into the
mercury in the cups M' M² respectively. While they are in this position, the
circuit is complete from L' through M¹ the coil W, M2 and F to L². The wire
coil W operates as a solenoid coil to which C acts as a core, and as C is fixed, the
coil is attracted towards E, but, while the current is moderate, the attraction is not
sufficient to move the coil from its position. If, however, the current should exceed
a pre-determined strength for which the instrument is adjusted, then the coil W
is moved over to the left, withdrawing the ends of the wire from the mercury cups
and so opening the circuit.
As the centre of gravity of the coil W passes the vertical line of the pivots P,
it falls over like a tumbling weight, and the circuit remains open until the coil W
is restored to its position. By adjusting the core C so as to penetrate more or less
into the coil W, the movement of the coil can be made to take place under various
strengths of current. Instead of an iron bar, the core C might be a tube, or it
might consist of a magnetic bar surrounded by a coil or of a magnetic tube enclosing
a coil. Also instead of making contact through mercury, the ends of the wire W
might make contact with solid metal.
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 1
claim is:
An appliance for cutting out an electrical circuit when the current exceeds a
certain strength, wherein a wire coil, enclosing an adjustable magnetic core and
forming part of the circuit while it is in a certain position, is pivotted so that
when the strength of current causes a certain amount of mutual attraction
between it and the core, the coil is made to move out of position and so to
open the circuit, substantially as described.
Dated this 2nd day of February 1891.
ABEL & IMRAY,
Agents for the Applicant.