IMPROVEMENTS IN APPARATUS FOR REGULATING ELECTRIC CURRENTS
Year: 1884

page_text: We, WILLIAM HARDING SCOTT of 2 St Mark's Terrace, Lakenham, Norwich,
Norfolk, Electrician, and EDWARD ALEXANDRE PARIS, of the same address,
Electrician, do hereby declare the nature of our said Invention for "IMPROVEMENTS
IN APPARATUS FOR REGULATING ELECTRIC CURRENTS," 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 :-
Our said Invention has for its object the improved construction and arrangement
of apparatus for regulating electric currents whereby the E. M. F. or current as
the case may be, may be maintained in a constant or a normal condition.
In carrying out, our Invention there is suspended vertically by a spring and
adjustment screw a soft iron core having at its bottom end a copper or iron plunger.
This plunger dips into a hole or well containing mercury formed in a number of
copper or iron plates insulated from each other and bolted by a framing to a sole
plate having in it a shallow well to form the bottom of the mercury well. The
soft iron core passes through a solenoid having part of its length within that
solenoid so that as by the action of the varying of the current in the solenoid the
iron core rises or falls, the plunger will in falling cause.the mercury to rise in the
well or vice versa. By this action the mercury will as it rises short circuit
resistances which are so arranged and connected to each of the series of copper or
iron plates forming the mercury well as to effect this object. The solenoid may be
wound either as a shunt or to be in series with the main current accordingly as it
is desired to keep the E. M. F. or the current constant. In either case the
movement of the plunger through the varying of the current round the solenoid
will take out or put in resistances by the action of the mercury.
And in order that our Invention and the manner of performing the same may be
properly understood we hereunto append a sheet of explanatory drawings to be
hereinafter referred to and representing our improved apparatus for regulating
electric currents. In these drawings the same reference numerals are used to mark
the same or like parts wherever they are repeated.
Figure 1 on the accompanying sheet of drawings is a vertical section and figure 2
is a horizontal section representing our improved apparatus. In this apparatus
there is bolted upon a sole plate 1, having a circular part in it, in which there is
cast a shallow circular depression or well 2, a number of copper plates 3 of a similar
form to the sole plate 1 but somewhat smaller. In this case there are, 14, plates
of copper (but there may be more or less if; desired) and there is a central circular

page_text: hole in each plate 3 which when the plates are placed one upon the other forms a
hollow or well in continuation of the well 2 in the sole plate 1. These plates are
insulated from each other by vulcanized fibre and they are fastened tightly together
to the sole plate 1 by two rods 4 which have screwed ends for fastening by screw
nuts to the sole plate 1. These rods are passed through holes formed for them in
the copper plates 3, and sole plate 1, and have shoulders or collars on them a little
distance from their ends which shoulders are brought by the action of the nuts in
screwing to bear on a copper plate 5 placed on the top of the plates 3 from which
plates the plate 5 is properly insulated. This plate 5 has in its centre a circular
hole similar to the plates 3 but it has a vertical flange or cup formed round the
hole 2. In the hole or well formed by the holes in the plates 3, there dips a copper
plunger 6 fitted to the lower end of a soft iron bar or core 7, which plunger 6 is
guided in the well by a rod passing up inside which is screwed through the bottom
of the sole plate. This core 7 is suspended at its upper end by a helical spring 8
attached to an adjusting screw 9. This screw 9 is fitted through a cross head
plate 10 carried on a collar at the upper ends of the bars 4 to which it is secured
by screw nuts. Placed nearly midway between this cross head plate 10 and the
copper plate 5 there is fixed to the rods 4 a brass bobbin or reel upon which wire
is wound forming a solenoid 11. This solenoid 11 is carried by its lower end upon
shoulders or collars formed near the middle of the bars 4 and it is secured thereon
by screw nuts at its upper end. The soft iron core 7 is so suspended that it is only
partly in this solenoid and consequently whenever the current passing round the
solenoid varies the iron core 7 will rise or fall as the case may be. By this rising
or falling of the core 7 the plunger 6 at its end which is of smaller diameter than
the well will cause mercury with which the well is partly filled to rise and fall.
Over the mercury in the well there is put a small quantity of paraffin or other non-
corrosive oil to keep the surfaces clean and prevent corrosive action. This rising
and falling of the level of the mercury will respectively put into or take out of
contact one or more of the copper plates 3 which plates 8 are each connected by
wires to resistances. These resistances are so arranged that as the mercury rises
in the well it will short circuit the resistances one after the other. The solenoid 11
may be wound either as a shunt or to be in series with the main current accordingly
as it is required to keep the E. M. F. or the current constant. In either case the
depression of the plunger through the varying of the current round the solenoid 11
will take out resistances by means of the mercury rising which may be either in
the field magnet circuit of a dynamo or in the main cireuit and so bring the E. M. F.
or the current very nearly to its normal condition. The apparatus is represented
in the drawings with the core and plunger in the position it would most probably
assume when a current was passing round the solenoid. When however no current
is passing, the plunger will be at the bottom of the mercury well.
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
wo claim is
The combination or arrangement of parts forming an improved electric current
or E. M. F. regulator substantially as herein before described with reference to the
accompanying drawings.