Improvements in and relating to Converters of Alternating Currents.
Year: 1890

page_text: Date of Application, 28th Aug., 1890-Accepted, 22nd Nov., 1890
COMPLETE SPECIFICATION.
Improvements in and relating to Converters of Alternating Currents.
RANKIN KENNEDY Electrical Engineer 10 India Street Kilmarnock Scotland do
hereby declare the nature of this invention and in what manner the same is to he
performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to the converting of alternating electric currents into
continuous currents or into motive power and has for its object to convert alternating
electric current into continuous current or power by the use of two pulsating uni-
direction currents derived by two rectifying commutators driven synchronously by an
alternating current motor from two alternating currents alternating at a difference of
phase equal to a quarter of a complete period using the two unidirection pulsating
currents for energising the field and armature of a dynamo electric machine having
two or more windings.
To produce power the field and armature are double wound to produce continuous
current the field is double wound and the armature treble wound.
In order to enable others skilled in the art to which my invention relates to under-
stand how it may be carried into effect or practice I have hereunto appended drawings
explanatory thereof, in which Fig. 1 represents a diagram elevation of a motor D
constructed in accordance with that described in my application for a Patent
No. 13190 of 22nd August 1890 and running at a speed synchronising and converting
alternating currents by rectifying them through rectifying commutators, well known
forms of commutators such as are described in the book of Sylvanus P. Thomson
"Dynamo Electric Machinery " pages 257 figure 205. On the shaft of the motor
are fixed the two commutators R R each having as many contact divisions as there
are of poles in field of motor D for the purpose of rectifying the two alternating
currents supplied by M M' and having a common return wire R Fig. 1.
A small portion of the currents drives the motor D and the rectified portions are
conveyed to a double wound dynamo electric machine shown in Figure 2 the one
pulsating unidirection current going through one winding on magnet N. S. and one
winding on armature A through commutator C, the other pulsating current going
through the other winding on magnet N. S. and through the other winding on
armature A through commutator the magnet and armature are thus energised
steadily and the dynamo electric machine gives off power at pulley K, in the same
way as a continuous current electromotor does.
In Figure 3 the motor 1) is driven by one alternating current supplied through
wires M R and the pulsating unidirection currents required for double wound
dynamo electric machine are derived from this alternating current the one direct
from commutator R and the other from generating coils on the armature of motor D
rectified through commutator R¹ by brushes F2 F3 and F6 F7.
Fig. 4 shows the arrangement of the dynamo electric machine for converting these
electric currents into one continuous current. The two pulsating unidirection
currents energise the field magnet N. S. and armature A the one current magnetising
at its maximum when the other is at a minimum the magnetism is very nearly steady,
the two unidirection pulsating currents act as the primary windings in a motor
generator and armature A is driven the third winding on the armature A is connected
to the third commutator C³ having brushes N. P. the one pulsating current energises
coil h on magnet N. S. and also one circuit on armature A connected to commutator C¹
the other pulsating current energises coil G, on magnet N. S. and also the other
circuit on armature A connected to commutator C, the driving of armature A and
energising of magnet N. S. by the two rectified alternating currents alternating at
quarter period difference generates a secondary current in the third coil of armature A

page_text: which current can be utilised in translating devices such as lamps or secondary
batteries, the winding of the armatures A are by the ordinary methods of Gramme
ring or Siemens drum windings for continuous current generators, and in practice the
limbs of the field magnets are double wound although for simplicity the two windings
are shown o ne on each limb.
The third coil on armature A Fig. 4 which generates. the secondary continuous
current is connected to commutator and the continuous current collected by
brushes N P for external use or work.
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. The combination of a double wound dynamo electric machine, with two
rectifying commutators driven by a synchronising motor converting two alternating
currents alternating at difference of phase equal to a quarter of a period into two
pulsating unidirection currents and energising the one winding by one of the pulsating
cirrents and energising the other windings by the other pulsating current substantially
as set forth for obtaining motive power.
2nd. A double wound dynamo electric machine having a double wound armature
and double wound field magnets a commutator to each winding on the armature in
combination with and energised by two pulsating unidirection currents derived from
two alternating currents alternating at a difference of quarter of a period, for
obtaining motive power substantially as set forth.
3rd. In a dynamo electric machine the combination of double wound field magnets
with an armature having three distinct windings each connected to a separate
commutator energised by two pulsating unidirection currents derived from two
alternating currents alternating at a difference of phase equal to a quarter of a period
the third circuit on the armature connected to the third commutator acting as a
secondary generator and supplying continuous current to translating devices
substantially as set forth.
Dated this 26th day of August 1890.
RANKIN KENNEDY.