Improvements in Means for Regulating or Controlling the Secondary Current Derived from Continuous Electric Current Transformers.
Year: 1888

page_text: Date of Application, 17th Mar., 1888
Complete Specification Left, 17th Dec., 1888
Comolete Soecification Accepted, 5th Feb., 1889
Improvements in Means for Regulating or Controlling the Secondary
Current Derived from Continuous Electric Current Transformers.
1 FRANK KING of 38 Chesilton Road Fulham in the County of Middlesex
Electrical Engineer do hereby declare the nature of this Invention to be as
follows:-
My Invention has for its object to maintain a uniform rate of current at all
times in the secondary circuit of a continuous electric current transformer when
the said secondary circuit is applied to the charging of a secondary battery whether
With this
the discharging circuit from the battery be receiving current or not.
object I couple up the several circuits of a continuous current transformer and
secondary battery combined so that as the electro-motive force of the battery varies
the intensity of the magnetic field in which the armature of the continuous current
transformer is rotated varies proportionally with the variation of the electro-motive
force of the battery. The electro-motive force for the maintenance of the proper
current will then be rendered by the secondary coils of the transformer armature and'
consequently the secondary circuit will be supplied with a uniform or nearly uniform
rate of current. I connect the primary circuit of the transformer armature to a
constant current generating dynamo in series, and connect the secondary circuit of the
said transformer armature to the battery charging circuit and I connect the field
magnet circuit of the transformer to the terminals of the battery to be charged. The
intensity of the magnetic field in which the armature rotates will then be proportional
to the condition of the electromotive force of the battery and the electromotive force
produced in the secondary coils of the armature by its rotation in the magnetic field
thus produced will be proportional to the said condition of electromotive force of the
battery, and in consequence, sufficient always for the purpose of producing a charging
current of normal amount.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C.,
Agents.

page_text: Improvements in Means for Regulating or Controlling the Secondary
Current Derived from Continuous Electric Current Transformers.
I FRANK KING of 38 Chesilton Road Fulham in the County of Middlesex
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 :-
My Invention has for its object to maintain a uniform rate of current at all times
in the secondary circuit of a continuous electric current transformer when the said
secondary circuit is applied to the charging of a secondary battery whether the
discharging circuit from the battery be receiving current or not. With this object 1
couple up the secondary circuit of a continuous current transformer and secondary
battery combined so that as the electro motive force of the battery varies, the intensity
of the magnetic field in which the armature of the continuous current transformer
is rotated also varies proportionally with the variation of the electro motive force of
the battery. The electro motive force for the maintenance of the proper current will
then be rendered by the secondary coils of the transformer armature and consequently
the secondary circuit will be supplied with a uniform or nearly uniform rate of
I connect the primary circuit of the transformer armature to a constant
current generating dynamo in series and connect the secondary circuit of the said
transformer armature to the battery charging circuit and I connect the field magnet
circuit of the transformer to the terminals of the battery to be charged. The intensity
of the magnetic field in which the armature rotates will then be proportional to the
condition of the electro motive force of the battery and the electro motive force
produced in the secondary coils of the armature by its rotation in the magnetic field.
thus produced will be proportional to the said condition of electro motive force
of the battery and in consequence sufficient always for the purpose of producing a
charging current of normal amount.
current.
And in order that my said Invention may be fully understood 1 shall now proceed
more particularly to describe the same and for that purpose shall refer to the several
figures on the annexed sheets of drawings the same letters of reference indicating
corresponding parts in all the Figures.
Figure 1 of the accompanying drawings is a diagrammatic illustration of my
improved combination in which A represents a continuous electric current transformer
or motor generator having one armature provided with motor or driving coils A
arranged side by side with the generator or secondary coils A2. Each of these coils
is provided with a separate commutator or collector preferably arranged one on either
side of the armature spindle. The field magnet coils e are connected to the terminals.
of the collectors or brushes which collect the current from the generator coils A² of
the armature as shewn by arrows 1 and 2. A secondary battery B is placed in
parallel (as shown by arrows 2) with the external circuit of the generator coils of the
armature and with the field magnet circuit as above indicated. If now a current of
uniform or constant quantity or rate be transmitted by the dynamo D to the motor
or driving coils A' of the armature A as shewn by arrows 3, it will be found that
whatever the electro motive force at the terminals of the battery (provided that such
electro motive force is not sufficient to pass a current of such amount as to

page_text: magnetically over saturate the field magnets) the current produced in the generator
coils A will also be uniform or constant in quantity and the electro motive force in
the said generator coils A2 will vary proportionally with the motions in the counter
electro-motive force of the external circuit of the generator. The dynamo D for
supplying the necessary electric energy to the circuit of the motor or driving coils A' of the
transformer A may be arranged in any suitable manner or with any suitable accessory
apparatus as commonly employed for ensuring the production of a uniform or constant
current with varying electro-motive force.
E is a diagrammatic representation of the external circuit from the generator coils
and secondary battery which is employed for supplying lamps or other devices for
utilizing the energy.
The apparatus operates in the following manner :—
The battery B being connected to the field magnets as before described, the dynamo
machine D is set in motion thereby producing a current in the circuit of the motor coils A¹
of the transformer, whereupon the transformer armature is set in motion causing the pro-
duction of a counter electro motive force in the said motor coils. This counter electro
motive force in the driving armature coils A¹ re-acts upon the electro-motive force of the
dynamo D until the electro motive force in the generator coils A2 of the armature is
sufficient to overcome the counter electro motive force of the battery B. The battery
is then switched into the circuit of the generator coils of the transformer and when
the total work produced by the generator coils A equals at the desired normal current
the total work produced by the dynamo machine D (minus the losses in transformation)
a current of constant quantity or rate will be produced in the generator circuit of the
transformer. This constant current will be applied to the various portions of the
external circuit for supplying the secondary battery, or battery and lamps or other
devices for utilizing the energy in proportion to their resistance or resistance and
counter electro-motive force. The normal current thus produced by the generator
coils A will not vary, whatever variation the external circuit may undergo, and this
condition of things will be maintained so long as the battery is connected to the field
magnet coils of the transformer and the dynamo D is kept at work at the necessary
speed, the whole combination thus accurately balancing itself.
Figure 2 represents an arrangement similar to that before described but illustrating
two dynamo machines D1 D2 connected, the one (D') acting as a motor and having its
armature attached to the constant current dynamo D as shown by arrows 3, and the
other (D) acting as a generator to the external circuit E or battery B and external
circuit E the field magnets of each of the two machines which form the motor
generator or transformer being excited by the secondary battery as described with
reference to Figure 1 and shown by arrows 1.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The combination of constant current dynamo machine or machines; continuous
current transformer or motor generator or transformers or motor generators;
secondary battery or batteries and external circuit or circuits therefrom for the
purpose of producing a constant rate of current in the secondary circuit of a con-
tinuous current transformer or motor generator or transformers or motor generators
substantially as herein before described.
Dated this 17th dov of December 1888