Improvements in the Means of and Apparatus for the Regulation of Electric Currents or their Effects.
Year: 1890

page_text: Date of Application, 12th June, 1890
Complete Specification Left, 12th Mar., 1891-Accepted, 16th May, 1891
PROVISIONAL SPECIFICATION.
Improvements in the Means of and Apparatus for the Regulation of
Electric Currents or their Effects.
We CHARLES RICHARDS HEAP and SIDNEY SHARP, both of Connaught
Mansions, Victoria Street, Westminster in the County of Middlesex, Electrical
Engineers, do hereby declare the nature of this invention to be as follows:-
This invention relates to certain improvements in the means of and apparatus for
the regulation of electric currents or their effects and has for its object to auto-
matically maintain constant, or approximately so, the current generated by a
dynamo or the speed of a motor to which such currents are imparted, and to
provide an efficient and simple apparatus for the purpose. According to our
invention we effect our object by altering the lead or position of the collecting
brushes upon the commutator to and from their position of maximum efficiency
thereupon.
This may be effected by attaching to the quadrant or frame carrying the brushes
a toothed wheel or sector and connecting same through suitable shafting and
gearing to a rack or equivalent operated as hereinafter indicated by a part of a
pneumatic or other fluid pressure motor. Such a motor may consist of two
cylinders fitted with reciprocating plungers and placed in communication above and
below same by two sets of passages controlled by a ported slide connected to and
actuated in one direction by a solenoid or electro-magnet (in electrical connection
with the generator) against the force of a spring constantly tending to move it in
the opposite direction. One of the plungers is driven by or from the main shaft of
the generator and by fluid pressure drives the other, which is connected to and
operates the collecting (or distributing) brushes when required in one direction or
the other according to the position of the slide. Or instead of employing a
reciprocal driving plunger as stated a rotary or any other suitable driving device
may be substituted.
In operation the action of the driving plunger or equivalent is to draw the air or
other fluid pressure from one side and force it to the other side of the driven
plunger, suitable valves being provided both in the driving plunger (if employed)
and in the passages and this action is controlled by the solenoid or equivalent.
When the current rises above the normal quantity the solenoid or electro-magnet
moves the slide so as to open one set of passages to change the pressure from one
side to the other of the driven plunger thus depressing it or raising it, the rack
then causing the pinion and shaft to move the position of the brushes in one direc-
tion or the other from the point of maximum efficiency upon the commutator so as
to reduce the current.
When the current falls below the normal the opposite action takes place viz. ;
the slide is moved by its spring overcoming the attractive power of the solenoid or
electro-magnet, thus opening the other set of passages when the driving plunger or
equivalent again varies the pressure and operates the driven plunger, the rack of
which returns the brushes towards the point of maximum efficiency on the com-
mutator and increases the current.
When the current is normal the slide takes a neutral position both sets of air
passages being equally open and the plungers, or one plunger and its equivalent
driving device, consequently in equilibrio.
The same motion of the driven plunger may be utilized in some cases for
switching resistances in and out of the main or other circuit by known intermediate
mechanisms as will be well understood.

page_text: Apparatus constructed on the same principle may be applied to an electro-motor
whereby its speed will be regulated in the manner above indicated.
Dated this 12th day of June 1890
J. C. CHAPMAN,
Agent.
COMPLETE SPECIFICATION.
Improvements in the Means of and Apparatus for the Regulation of
Electric Currents or their Effects.
We CHARLES RICHARDS HEAP, and SIDNEY SHARP, both of Connaught
Mansions, Victoria Street, Westminster in the County of Middlesex, 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:―
This invention relates to certain improvements in the means of and apparatus for
the regulation of electric currents or their effects and has for its object to auto-
matically maintain constant, or approximately so, the current generated by a
dynamo or the speed of a motor to which such currents are imparted, and to
provide an efficient and simple apparatus for the purpose.
According to our invention we effect our object by altering the lead or position
of the collecting brushes upon the commutator of the generator or motor to or
from their position of maximum efficiency thereupon automatically through the
medium of an electrically controlled apparatus driven by the generator motor or
other running device, and adapted to vary the pressure of any suitable fluid acting
upon a part or parts of the said apparatus connected to the brush carriers in such
manner and at such times as hereinafter appear.
We will fully describe our invention in reference to the accompanying drawings
which diagrammatically indicate one apparatus by which our invention may be
performed, and in which like letters refer to like parts.
Figure 1 is a sectional plan: Figures 2 and 3 are sectional elevations respectively
on lines 1, 2, 3, 4, and 1, 5, 6, 4 of Figure 1. Figure 4 is an elevation of ported
slide plate; and Figures 5 and 6 are respectively face and back clevations of fixed
plates Figures 7, 8, and 9 are cross sections of sliding and fixed plates showing
central and extreme positions.
The apparatus illustrated consists of a closed chamber A which may be cast or
built up of iron or other suitable material. It includes two cylinders B and C of
different diameters in which work the respective plungers b, c, between the cylinders
are disposed certain passages E, F, G, H, for the fluid pressure employed (herein-
after called "air ways") and a ported slide K for controlling same: The chamber A
is provided with an air tight cover a which may be conveniently made in
removable sections bolted or studded to the sides so that all parts are accessible.
In the smaller cylinder C works plunger c with a downwardly opening valve c²,
its rod c² guided by usual side bars is connected by connecting rod to a crank or
disc crank c fixed upon the main axle d of the generator.
The brush holders D are arranged upon the bearing d¹ of the dynamo shaft das
usual or otherwise, but in such a manner as to be rotatable on their seating when
automatically operated as hereinafter described.
The rod of the larger plunger works through the usual stuffing box, the
travel of the plunger b being limited by stops a a', and has a rack 3 with which
gears a pinion 3 upon a short shaft supported in bearings 6. This shaft is
connected through a belt P and pulleys p' p' as illustrated (but it may be by any
other. suitable gearings or connections according to individual cases), to the quadrant
frame or other rotatable brush carrier D above described.
Between the cylinders B and C are arranged two sets of air ways E and F.
The function of one set is to raise the plunger and that of the other to depress
Bame at the required times. They may be arranged at either side of a central

page_text: partition as illustrated in Figure 1 or otherwise. The lower part of cylinder B,
see Figure 2, is placed in communication by passage E (as shown by the crooked
arrow) with the upper part of cylinder C; and the upper part of cylinder B
communicates by passage G with common aperture at the top of the cylinder C which
is controlled by an inwardly opening valve e. In the other set of passages the
lower part of cylinder C communicates by passage H with the lower part of
cylinder B, and the lower part of cylinder C also communicates by passage F with
the upper part of cylinder B, an inwardly opening valve being arranged at the
common aperture as illustrated at Figure 3.
The whole of the aforesaid air-ways E, F, G, H, are controlled by one plate K
arranged to slide for a limited distance between two face plates M, N. In the
plate are formed four ports ¹, k², k³, k, and in the two fixed plates M, N, are
also formed ports m³, m², m³, m²; n², n², n³, n', see Figures 4, 5, and 6.
The ports
in the fixed plates M.N are opposite one another but those in the sliding plate K
make connection as follows :
When the plate K is in its central or neutral position, see Figure 7, all ports are
closed and the parts in equilibrio. When it is moved to its highest position, see
Figure 8, k, m, n', and ', m, n, coincide and open passages GH, closing E and F.
When is moved to its lowest position, see Figure 9, k², m², n², and k³, m³, n³,
coincide and open passages E and F, closing G and H, thus reversing the direction
of motion of plunger & in cylinder B.
The sliding plate K is operated in a downward direction by the action of a
solenoid S or electro-magnet electrically connected to the generator or other source
of electricity and acting on a core attached to plate K; and in an upward
direction by the action of an adjustable spring such as S either directly or through
levers, or weight and chain or other mechanical equivalent may be substituted for
the spring shown.
The air ways E, F, G, H, are illustrated as being in two vertical planes side by
side but they may be arranged otherwise in any convenient planes or manners.
The slide plate may also be arranged to work horizontally or otherwise in any
convenient manner.
Instead of employing a reciprocal driving plungere such as above set forth, a
rotary blower or any other suitable driving device may be substituted as will be
readily understood.
In operation the action is as follows:-The revolution of shaft d constantly
drives the plunger c. The slide K is set in such position that when the current is
normal the slide is neutral, see Figure 7, in which position all air passages are
closed, the pressure being allowed to escape at a suitably adjusted relief valve, or
otherwise or the ports in the slide and the position of the slide may be arranged
so that when the current is normal and the slide neutral all ports are open, and
hence in either case equilibrium exists and the pressure escapes freely.
When the current rises above the normal quantity its action causes the solenoid $
to draw down core & so as to open the air ways E and F, then on descent of the
plunger the valve opens and pressure is applied to the top of the driven
plunger thus depressing it, the air below it being driven out through E and e;
the rack then through pinion 63 and connections P and moves the collecting
brushes D away from their position of maximum efficiency upon the commutator,
and thus the current is automatically reduced. When the current falls below the
normal quantity the opposite action takes place, viz. -the slide K is raised by the
force of the spring s or equivalent overcoming the power of the solenoid S thus
closing E and F and opening the other set of air passages G and H. Then the
descent of driving plunger c again varies the direction of pressure in B and
operates the driven plunger bin the opposite direction to that above described, thus
returning the collecting brushes towards the position of maximum efficiency on the
commutator and automatically increasing the current as required. In other words
when E and F are open the fluid pressure will be transmitted to the upper side of
piston in the direction of the crooked arrow Figure 3, and will escape from

page_text: beneath same in the direction of the crooked arrow Figure 2; and conversely,
when E and F are closed the fluid pressure transmitted to the lower side of plunger b
will follow the path of the straight arrow at H. Figure 3, and will escape in the
path of the straight arrow at G Figure 2.
The same motion of the driven plunger 6 may be utilized in some cases for
switching resistances such as lamps and so forth in or out of the main or other
circuit by known intermediate mechanisms as will be well understood by those
skilled in the art. Apparatus constructed on the same principle may be easily
applied to an electro-motor whereby its speed will be regulated in the manner above
indicated.
A device is illustrated in Figure 2 for preventing liability to breakage in the
event of overheating or defective working of the plunger e or other part of the
above described regulating apparatus: This consists of a spring T fixed to the crank
arm and engaging with ratchet teeth t formed on the periphery of the disc d :
normally the spring T revolves with the disc, but should any accident occur its
resistance will lift it over the teeth and the regulating apparatus would be brought
to a standstill, while the chattering of the spring T on teeth t would attract the
attention of the attendant.
We have only described one form of apparatus and its connections but it is
obvious that the principle may be carried into effect by various modified arrange-
ments without departing from the main feature of the invention.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. The herein before decribed means of automatically effecting the regulation of
electric currents or their effects by altering the position of the collecting brushes
on the commutator of the generator or other motor in accordance with quantity of
current to and from their position of maximum efficiency thereupon through the
medium of an electrically controlled fluid pressure apparatus constructed connected
and operating substantially in the manner hereinabove set forth.
2. An apparatus for the purposes. herein above set forth having a plunger or
equivalent such as c driven by the generator or other motor and driving a plunger
or equivalent such as ó mechanically connected to the brush carriers, the action of
the fluid pressure on the latter plunger being controlled and varied as required by a
spring pressed slide plate operated by a solenoid or equivalent in electrical connee-
tion with the generator motor or other source of electricity substantially as set
forth.
3. In a fluid pressure apparatus for regulating electric currents and their effects
the combination with the driving plunger blower or equivalent c and the driven
and operating plunger b, of the arrangement of fluid passages E. F. and G. H. with
valves e and f, and the ported spring pressed slide K electrically controlled and
automatically operating the brushes as and when required. substantially as and for
the purpose set forth.
4. The combination and arrangement of the plungers, air passages, valves, ported
slide with core and spring, solenoid, and the mechanical connection of rod ¹ to the
brush carrier D, and with or without the safety arrangement T, t, all substantially
and for the purposes described and illustrated in the accompanying drawings.
Dated this 19th day of March 1891
J. C. CHAPMAN.