Improvements in the Method of Electrically Governing the Voltage of Dynamos and Speed of Engines.
Year: 1894

page_text: Date of Application; 12th Sept., 1894
Complete Specification Left, 5th June, 1895-Accepted, 3rd Aug.,
1895
Improvements in the Method of Electrically Governing the Voltage
of Dynamos and Speed of Engines.
We, JESSE GRAHAM and HARRY CHAPMAN, both of Queen Street, Morley, in
the County of York, Electrical Engineers, do hereby declare the nature of this
invention to be as follows:-
This invention has for its object the arrangement and combination of certain
mechanism in a novel manner by which the voltage of dynamos and speed of
engines may be regulated in accordance with the variations in the strength or
voltage of the electric current.
We accomplish our object in the following manner: Positive and negative wires
connect a. dynamo with an electro magnet or solenoid, to which is connected an
armature or plunger as the case may be, the armature or plunger moving contact
pieces according to the variation of current.
The end of the armature terminates with a cross piece between two metallic
stops, each of which is coupled by a wire to an electro magnet. When the
current from the dynamo driven by the engine to be governed is at the required
strength of voltage, the core of the solenoid or the armature of the electro magnet
is attracted to a certain position, so that the before mentioned cross piece is held
between the metallic stops, but not in contact with either.
Should the current decrease, the plunger or armature alters its position, bringing
the cross piece into contact with one of the metallic stops, the current then flows
through the electro magnet connected therewith, and back to the negative wire,
with the result that, an arm jointed to the magnet is quickly vibrated in such a
manner that the end comes in contact with a pinion mounted on a shaft and
rotates same, thereby causing another pinion geared with a rack to operate the
latter in a sliding direction, by which operation, the resistance is cut from the
shunt wire of the field magnet of dynamo, causing more current to flow around
them, thus bringing the current back to the required voltage, when the. armature
between the metallic stops is liberated.
If the current is too great, the armature is attracted in the opposite direction,
thus operating the electro magnet connected therewith, by which the rack is moved
in the opposite direction and the current regulated accordingly.
By connecting the before mentioned pinion or rack with the spindle of an engine
steam supply valve, the flow of steam may be regulated by the opening and
closing of the said valve.
Dated this 10th day of Sentember 1894

page_text: Improvements in the Method of Electrically Governing the Voltage
of Dynamos and Speed of Engines.
We, JESSE GRAHAM and HARRY CHAPMAN, both of Morley, near Leeds, in
the County of York, Electrical Engineers, 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 :-
The object of this invention is to construct apparatus whereby the variations
in strength of a current of electricity are caused to regulate the voltage of
dynamos or the speed of engines thereby causing the dynamo or engine to run
at a regular speed, and thus produce a more regular and constant current.
In order that our invention may be clearly understood we will proceed to
describe same with reference to the accompanying drawings, in which similar
letters refer to like parts in all the figures.
Fig. 1 is a front elevation of an apparatus constructed according to our invention,
and Fig. 2 is a side elevation of same.
Fig. 3 is a view of a slightly modified form of the apparatus.
According to our invention we employ electro magnets A and B, the wires C
of which are connected together, and the said wires C communicate with the
electric circuit which is required to be governed. D is an armature which is
connected to a bracket D₁ by a spring D³, and a set screw D' is provided for
regulating the strength of the spring D. E is a needle which is connected to the
spring D, and the lower end of the neelle is situated between metallic stops F
and G, in such a manner that the spring D' tends to keep the needle E in contact
with the metallic stop G. The electro magnet B is provided with an armature B
which is kept in contact with the terminal B when a current is passing through
the wire C, owing to the magnetic attraction of the electro magnet B; but when
no current is passing through the wire C, the armature B' falls and the connection
is broken between the terminal B' and the said armature B'.
A pinion H is mounted on a shaft J which is formed with a screw thread on its
surface, and an arm K is so connected to the shaft J as to be moved backwards or
forwards according to the direction of rotation of the said shaft J. L and M are
electro magnets carrying vibrating armatures L' and M', which are mounted in the
ordinary manner and carry jointed hammer ends L2 and M' on their outer ends, in
such a manner that on the vibrating of the armatures L' or M¹, the hammer
ends L or M³ strike the teeth on the pinion H, which is thereby turned to the right
or left according to which armature is vibrating.
The electro magnet L is connected to the metallic stop F by means of the
wire N, and the electro-magnet M is connected with the metallic stop G by means
of the wire P.
When a current of electricity is being governed, the set screw D' is adjusted
against the spring D' to suit the voltage required, and as long as the voltage of
the current remains constant, the attraction of the electro magnet A on the
armature D counterbalances the effect of the spring D' and keeps the needle E
between the metallic stops F and G. However, should the current increase above
the required strength, the attraction of the electro-magnet A on the armature D
overcomes the spring D and brings the needle E into contact with the metallic
stop F. This establishes a circuit through the wire A', bracket D', spring D',
needle E, stop F, wire N, electro magnet L, wire Lo, terminal B³, armature B¹ and
wire B, thereby setting in motion the hammer L' and causing the pinion H with
its shaft J to be turned, which latter moves the arm K and actuates a resistance R
which reduces the current until the needle E becomes again balanced between the
stops F and G. Should the current decrease below the required strength, the

page_text: spring D overcomes the attraction of the magnet A on the armature D, and
the needle E coming into contact with the stop G, a current is passed through the
electro magnet M, and the hammer end M' coming into play, turns the pinion H
and shaft J in the reverse direction, thereby moving the arm K so as to increase.
the current back to the required strength. If the circuit through the coils on the
electro magnets A and B should be broken, the apparatus is thrown out of action
by the armature B₁ falling from the electro magnet B, and thus damage from the.
excessive action of the hammers in one direction is averted.
In some cases it is required to regulate a current of electricity with exceptional
speed, and for this purpose we employ a slightly modified form of apparatus shown
at Fig. 3. In this arrangement the coils of the electro magnets L and M are each
divided into two sections L³ L, and M³ M*, which are separately connected to the
stops F F and G G' by wires N N and P P. The needle E has two auxiliary
springs E and E' on same which are of very light construction.
When the current increases, the spring E' comes into contact with the stop F
and makes a connection through the coil L³ of the electro magnet L, which brings
the hammer end L into play and turns the pinion H in the required direction, but
if the action is not quick enough and the current continues to increase too.
quickly for regulation by one coil, the lower end of the needle E comes into
contact with the stop F¹, thus bringing the second coil L into action, and the two
coils working on the same electro magnet cause the hammer L' to work quickly
until the current is nearly reduced to the required extent, when the needle E leaves
the stop F and the coil L' is left to work the hammer L' so as to regulate the
pinion H to the extent required.
+
Instead of employing two coils on the electro magnets as above described, we
could employ two springs on the armatures and two regulating screws, the latter
being connected to the double metallic stops, in a similar manner to that above
described.
In Fig. 2 of the drawings we have shown an arm K in connection with an
ordinary electrical resistance R, but the screw on the shaft J may equally well be
connected to the throttle valve of an engine, or to speed mechanism on a dynamo,.
whereby the current of electricity generated may be regulated to the required
degree.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The electro magnets L and M carrying hammers L' and M', the pinion H and
shaft J, in combination with suitable switch mechanism, substantially as and for
the purposes set forth.
2. The electro maguet A, armature D, bracket D', spring D³, set screw D³,
needle E and stops F and G, substantially as and for the purposes set forth.
3. The electro inagnets A and B and parts connected therewith, connected
by wire C to the circuit of electricity to be governed, substantially as set forth.
4. The combination of the parts forming the apparatus for regulating the
strength of a current of electricity, substantially as shown and described with
reference to Figures 1 and 2 of the accompanying drawings.
5. The combination of parts forming the apparatus for regulating the strength
of a current of electricity, substantially as shown and described with reference to
Fig. 3 of the accompanying drawings.
Dated this 5th day of June 1895.
BREWER & SON,
London and Leeds, Agents for Applicants.