Improvements in Electric Switches and Cutouts.
Year: 1899

page_text: Date of Application, 11th Apr., 1899
Complete Specification Left, 11th Jan., 1900-Accepted, 17th Feb., 1900
PROVISIONAL SPECIFICATION.
Improvements in Electric Switches and Cutouts.
We, CROMPTON AND COMPANY LIMITED, of the Arc Works, Chelmsford, in
the County of Essex, Electrical Engineers, and HENRY WILLIAM WARTNABY, DIX,
of No. 30, Hamlet Road, Chelmsford aforesaid, Electrical Engineer, do hereby
declare the nature of this invention to be as follows:-
Our invention relates to that class of electric switches in which the operation
of the switch is controlled by an electro magnet or solenoid and in which
the action of the switch has to depend in some way on the current flowing in
the circuit in which the switch is placed as distinguished from those electrically
controlled switches, the action of which depends solely on the electro motive
force of the circuit in which they are placed.
Our invention has for its object the simplification of the construction of the
said electro magnets or solenoids.
At present switches whose action has fo be controlled by the current passing
in the circuit in which they are placed are constructed so that the whole
current of the circuit passes through the coils or windings of the one or more
electro magnets or solenoids controlling the said switches in addition to passing
through the switch itself. When therefore these switches have to be made
for circuits carrying large currents the coils or windings of the electro magnets
or solenoids become unduly large and expensive to make.
By our invention instead of passing the whole current of the circuit in which
the switch is placed through the coils of the one or more electro magnets or
solenoids, we pass the greater portion of it through a shunt to the terminals of
which the coils of the one or more electro magnets or solenoids are attached (the
switch itself carrying the whole of the current as before).
By this means we cause only a small portion of the current in the circuit to
pass through these coils which may therefore be made of much smaller section
and so more easily
or
and
cheaply.
The shunt is preferably a straight bar made of any suitable conductor of
electricity though it may be of any other convenient shape provided that it
fulfils its function of diverting a proper proportion of the current flowing in
the circuit from the coils of the one or more electro magnets or solenoids which
control the switch.
Our invention is specially applicable to the magnet coils of excess minimum
or non-return switches, but it can be equally applied to the electro magnets or
solenoids of current controlled switches to be used for any purpose whatever.
Dated the 11th day of April 1899
WM. BROOKES & SON,
55 & 56, Chancery Lane, London,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Switches and Cut-outs.
We, CROMPTON, AND. COMPANY LIMITED, of the Arc Works, Chelinsford, in
the County of Essex, Electrical Engineers, and HENRY WILLIAM WARTNABY DIX,
of No. 30, Hamlet Road, Chelmsford, aforesaid, Electrical Engineer, 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:→
Our invention relates to that class of electric switches in which the operation
of the switch is controlled. by an electro magnet or solenoid and in which
the action of the switch has to depend in some way on the current flowing in
the circuit in. which the switch is placed as distinguished from those electrically
controlled switches the action of which depends solely on the electro motive
force of the circuit in which they are placed.
Our invention has for its object the simplification of the construction of the
said electro magnets or solenoids.
At present switches whose action has to be controlled by the current passing
in the circuit in which they are placed are constructed so that the whole of the
current of the circuit passes through the coils or windings of the one or more
electro magnets or solenoids, controlling the said switch in addition to passing
through the switch itself. When therefore these switches have to be made
for circuits carrying large currents the coils or windings of the electro magnets
or solenoids become unduly large and expensive to make.
Figure 1 is a diagrammatic view of the switch. The apparatus is coupled
into any desired circuit between the two terminals A and B. At the point O
the current is branched into the two circuits namely the shunt circuit of low
resistance D and that of high resistance d. E is an electro magnetic device
actuated by the current in the shunt D and having a moving part e which by
its relative position to the catch F mounted on the lever G can control the
movement of the latter so that the lever arm is in such a position as to complete
the circuit at the time when the current passing through D being small the
moving part e is not attracted but when the current passing through is a
increased to any desired extent the catch f is lifted and the lever is released and
either by the weight shown or by a spring or other means the circuit is
interrupted at the point H. This is only one of many methods by which the
principle of shunting an interrupter switch can be employed. The shunt D
is preferably a straight bar made of any suitable conductor of electricity a
although it may be made of any other convenient shape.
Our invention is specially applicable to the magnet coils of excess minimum
or non-return switches, but it can be specially applied to the electro magnets or
solenoids of current controlled switches to be used for any purpose whatever.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is:-
In automatic cut off switches the arrangement of the electro magnetic devices
which actuate the mechanism in parallel circuits as and for the purposes herein
described.
4
0.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London,
Agents for the Applicants.