Year: 1887

page_text: J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, W.C.
Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in Means for the Distribution of Electricity.
I HENRY EDMUNDS of 10 Hatton Garden 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 :-
The object of my Invention is to provide means whereby electric currents for
utilization at any required points can be derived from a circuit common to the system
in a convenient and efficient manner and in such way that the derived current
automatically controls the supply of current to itself from the common circuit the
places of utilization being in series with each.other on the main supply.
At each place where current is to be taken off and utilized I provide what I term a
"motor generator" that is an apparatus or device combining means for obtaining
motion from the common circuit and means for generating or converting the motion
into a current for utilization at the required places.
In order that this invention may be clearly understood I will now describe the same
with reference to the accompanying drawings.
The motor generator 4 (in Figures 1. 2. 3. 4. 5. 6 and 8) consists of three principal
parts the field magnets 5. 6. the motor armature 10 (which is the means of obtaining
motion from the common circuit) and the generator armature 11 (which is the means
whereby the said motion is converted into current for utilization). The motor
armature is connected with a main supply constant current circuit 1. 1. (Figure 8
energised say from a dynamo at a central station and the generator armature supplies
the circuit of utilization locally. The field magnets may be either excited in series
with the motor-armature or may be in shunt or compound therewith from the main
circuit or in series with the main and local circuits or in series with main and
compound with local by double winding or in some cases may be separately excited
from another source and at the same time be in series with the local circuit these
arrangements being illustrated by Figures 1. 2. 3. 4. 5 and 6 respectively these
different windings and connections being arranged according to the requirements of
the work. The motor-generator may be employed to supply a local installation as
illustrated in Figure 7 where the motor-generator consists of field-magnets 5, 6 with
one armature, with two commutators and two windings, each distinct circuits, one (10)
connected with the main the other (11) with the local (the former being a
"motor
winding and the latter a generator winding) the sizes of wires and number of
layers of each being arranged according to the effects I wish to produce, as in con-
verting a current of high electro-motive force and small quantity to one of low
electro-motive force and large quantity and vice versa. The field-magnets being excited
in series, shunt or compound, from either sections of the armature or both, or
differentially wound as may be required according to the work desired or it may be
used as an auxiliary to a battery circuit, in order to re-inforce a larger demand of
"

page_text: current than the battery could supply. In this case I arrange it with accessories in
the manner which I will now describe with reference to Figure 8 in which 1. 1. is
the main circuit wherein at 2 is a set of storage batteries which may be receiving
charge in the manner described in my Patent Number 8641 of A.D. 1887 said storage
batteries supplying current to lamps 3 in the local circuit 7 and in its supplementary
circuit 7".
The motor generator 4 has field magnets 5. 6 which are energised from the
batteries 2 in conjunction with the supplementary local circuit 7". 10 is the armature
belonging to the motor portion of the "motor generator" and 11 is the armature
belonging to the generator portion of the same. Both these armatures being fixed
upon the same shaft revolve together, and the field magnets 56 are
to both.
commo:
Current for the motor armature is supplied by the main circuit which circuit is
open or closed through the mercury cups 12, 14 and their bridge 13, the motor being
in the path 15 now let an abnormal increase of demand occur, by reason of more
lamps being thrown into the supplement 7" to the local circuit 7 by the operation of
a switch at 25 the consequent increase of current therein from the batteries will cause
a solenoid 16 to attract the armature 17 upon one end of the rocking lever 18 where-
upon the other end of the said lever will rise, lifting the bridge 13 out of the inercury
cups 14 and 12 and breaking the main circuit at those places and also closing at 12"
and 14 by the bridge 13 exciting the circuit of the field of the motor generator.
Thus the current in the main circuit I passes through the motor armature 10, and
that armature will be rotated, as also will the generator armature 11, the latter
supplying current to the supplementary portion 7 of the local circuit 7 which is
normally open at the mercury cups 19 and 21 but which is closed through the fine
wire shunt and solenoid 22. Thus as soon as the current in this shunt 22 is sufficient
to attract the armature 23 on the rocking lever 24 the supplementary portion 7" of
the local circuit 7 is closed through the mercury cups 19 and 21 by the descent of the
bridge 20, and as before stated the current in this circuit supplements the current
from the batteries. When the work is sufficiently diminished so that the motor-
generator is not required, the consequent lessening of the amount of current in the
solenoid 16 would result in the fall of the bridge 13 and the closure of the main circuit
past the motor generator 4 whereupon it would cease to operate until next called into
action.
Τ
Should it be desirable to prevent undue discharge from batteries when employed in
connection with a motor-generator owing to stoppage of the generator the two
circuits 7, 7ª may be arranged so that the one from the batteries, includes only work
equal to the normal discharge, the second circuit including work in addition to that in
the aforesaid may be automatically disconnected therefrom in case of over-discharge
from the battery on stoppage of the motor-generator in the following manner.
provide an armature 27 at one end of a weighted rocking lever 29 the other end of
which carries the bridge 30 appertaining to the mercury cups 31, 32 in the local
supplementary circuit 7. The armature 27 is upheld so long as any current exists
in the main circuit I by the action of the solenoid 33 in the path 15 from that main
circuit bnt upon the cessation of current in the main circuit and consequently in
the solenoid 33 the end of the rocking lever 29 carrying, the armature 27 falls and
simultaneously breaks the circuit 7 by lifting the bridge 30 out of the mercury
cups 31, 32.
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.
1st. A system of distribution of electric currents wherein a main circuit supplies
current to actuate at each place where the current is to be utilized a device which I
have termed " a motor generator" that is to say a device driven by the current of
the main circuit and giving off current to the places of utilization the said places
of utilization being in series with each other on the main supply.

page_text: 2nd. A "motor-generator" consisting of field magnets with two armatures (or two
windings on one armature) and two commutators and distinct circuits one connected
with the main the other with the local the field magnets being excited in series,
shunt or compound from either sections of the armature or both, or differentially
wound according to the work desired substantially as described.
3rd. For the purpose described a "motor-generator" consisting of a magnetic field
or fields and two armature windings one appertaining to the main circuit and one to
the sub-circuit as described.
4th. In a * motor-generator "the combination of two armatures (or two windings
on one armature) and two commutators on the same shaft (one for the main and one
for the local currents) with a magnetic field a portion of which is excited by current
in series with the armature (or winding) connected with the main and another portion
of which field is excited by current in series with the armature (or winding) supplying
a local circuit.
5th. For distributing electric currents in the manner hereinbefore described and
claimed the arrangement described with reference to Figure 8 of the accompanying
drawings.