Improvements in and Pertaining to Electric Motors and their Application for Charging Secondary Batteries or Accumulators.
Year: 1887

page_text: Date of Application, 14th Nov., 1887
Complete Specification Left, 14th Aug., 1888
Complete Specification Accepted, 21st Sept., 1888
Improvements in and Pertaining to Electric Motors and their
Application for Charging Secondary Batteries or Accumulators.
I, WILLIAM MORRIS MORDEY of Victoria Works, Belvedere Road, Lambeth in the
County of Surrey, Electrician, do hereby declare the nature of this invention to be
as follows:-
This invention has reference to improvements in the construction of alternate-
current electric motors, and to their application in connection with secondary batteries
or accumulators for charging the same.
Heretofore so far as I know no practical and satisfactory alternate-current electric
motor has been made.
It is known that an ordinary alternate-current generator is capable of being used
as an alternate-current motor under certain conditions, but no practical use has been
made of such machines for this purpose. They are difficult to start from a state of
rest particularly when the generator is running at full speed because they require to
synchronise with such generator.
Furthermore it is known that an ordinary continuous current motor will run when
supplied with alternate-currents. Such motors although capable of starting from a
state of rest when current is supplied to them, are of low efficiency and do not possess
the speed regulating properties resulting from the before mentioned synchronous
action.
The main object of this invention is the construction of alternate-current motors
which shall possess the power of starting from a state of rest, the speed-regulating
properties attaching to synchronous action, and a high efficiency.
The nature of this part of my invention will be understood from the following
description of one method of carrying it into effect, as applied to a motor having a
Siemens or a Gramme type of armature, provided with a Gramme collector. On the
shaft is placed a simple commutator for instance, one formed of two parts provided
with brushes. The alternate-current mains are respectively connected to these
brushes, while the commutator plates or segments are joined by means of suitable

page_text: rubbing contacts, to the terminals of the motor; that is, if it be a series motor
respectively to one of the collector brushes and to the end of the field circuit. The
field-magnet is preferably suitably laminated. On switching the whole arrangement
into connection with the alternate-current supply circuit the motor will start from a
state of rest; but as its speed is at first slow, the armature and fields are supplied with
an alternating current. As the speed increases the action of the commutator gradually
reduces the alternations until the motor is traversed by a current which is continuous
in direction. This occurs, with a two-part commutator, when the alternations of the
supply current correspond in rate with the revolutions of the shaft. The tendency of
the motor to increase its speed until this synchronism is attained is due to the fact
that the more the rate of the alternations of the current traversing it are reduced,
the more powerful does the motor action become. When this condition of synchronous
action is reached, the motor maintains a constant or nearly constant or synchronous
rate of rotation. Any excess of speed beyond this amount is checked by a loss of
power due to the alternations setting up inductive reactions, while any diminution of
speed is counteracted (within the range of power of the motor) by the inherent
tendency of the arrangement to endeavour to attain synchronism.
It is however preferred to dispense with the collector, and to fit the motor with
only a commutator. For this purpose the armature is preferably wound with
several open coils, the ends of which are connected to the plates or segments of the
said commutator. These plates or segments are preferably made over-lapping and
with gaps between them, in the manner usual in open coil armatures, for the purpose
of preventing short-circuiting of any coil, or open-circuiting of the armature.
Similarly, the field circuit is connected to certain plates or segments of the com-
mutator and may be divided into two or more circuits. It will be understood that
as the speed of the motor is determined by the number of parts of the commutator,
it is necessary to arrange the number of parts, with reference to the rate of alterna-
tions of the supply current, to give the required rate of speed. To prevent sparking
at the commutator (which, however, except to a small extent, only occurs when
synchronism is departed from) the gaps of the commutator may be shunted by a
liquid or other resistance.
In order to render the commuted or rectified current fairly constant in amount
as well as continuous in direction I sometimes insert in the motor circuit an induc-
tional resistance of any suitable kind.
For the purpose of enabling accumulators or secondary batteries to be charged
from alternate-current circuits, either directly or through the medium of transformers,
a motor constructed in accordance with this invention is employed to drive a rotating
commutator, the plates or segments of which are connected to the battery, while the
brushes are joined to the alternate-current main. As the E.M.F. of a commuted
or rectified alternate current falls to zero between each pulsation, an arrangement
such as the above cannot be used alone with success for the purpose of charging
accumulators, as the discharge therefrom, during the portions of the pulsation or
wave when the E.M.F. falls below that of the cells, gives rise to destructive
sparking and waste of energy. To overcome this difficulty I interpose in the
charging circuit an inductional resistance, whose electro-magnetic inertia converts
the pulsating current into an approximately regular one, thereby preventing the
wave of E.M.F. and current from falling to zero or from rising above a pre-
determined maximum, thus maintaining throughout the whole phase, a current
suitable for charging accumulators.
Dated this 11th
זג
בד
1000
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C.
Agent for the Applicant.

page_text: Improvements in and Pertaining to Electric Motors and their
Application for Charging Secondary Batteries or Accumulators.
I, WILLIAM MORRIS MORDEY, of Victoria Works, Belvedere Road, Lambeth in
the County of Surrey Electrician, 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 has reference to improvements in the construction of alternate
current electric motors, and to their application in connection with secondary
batteries or accumulators for charging the same.
Heretofore so far as I know no practical and satisfactory alternate current electric
motor has been made.
It is known that an ordinary alternate current generator is capable of being used
as an alternate current motor under certain conditions but no practical use has been
made of such machines for this purpose.
They are difficult to start from a state of rest particularly when the generator is
running at full speed, because they require to synchronise with such generator.
Furthermore it is known that an ordinary continuous current motor will run when
supplied with alternate currents. Such motors although capable of starting from a
state of rest when current is supplied to them, are of low efficiency and do not possess
the speed regulating properties resulting from the before mentioned synchronous
action.
The main object of this invention is the construction of alternate current motors
which shall possess the power of starting from a state of rest, the speed regulating
properties attaching to synchronous action, and a high efficiency.
The nature of this part of my invention will be understood from the following
description of one method of carrying it into effect, as applied to a motor having a
Siemens or Gramme type of armature, provided with a Gramme collector.
Figure 1 shews diagrammatically the arrangement of the parts.
C is the collector of an armature of an ordinary continuous current type, F is the
field winding which is wound or placed on a field magnet preferably suitably divided
as by being constructed of iron wire or sheet iron. This field winding is most
advantageously connected in series with the armature, but may be shunt or partly
shunt and partly series. Making contact with the collector C are two brushes B B³.
On the shaft or axle which carries the armature with its collector C a commutator C¹
is fixed-This commutator C¹ may be of simple form but in order to prevent or
reduce sparking and to assist the synchronizing action I prefer to use the constructions
shewn in Fig. 1. by which a suitable liquid or other resistance is or may under
certain conditions be made to act as a partial shunt at the gaps of the commutator.

page_text: S S¹ are commutator plates or segments connected by rubbing contacts respectively
with the terminals T T¹ of the motor. bb¹ are brushes bearing on the commutator (¹
and connected to the alternate current mains m m¹.
In the case of a series motor as in figure 1 the terminal T is connected with one
brush B, the other brush B' being joined to one end of the field winding F, T¹ being
the other terminal of the motor.
Between the ends of the plates or segments S. S¹ are small plates or segments s s¹
which may be connected by rubbing contacts with a suitable liquid or other
resistance R.
On switching the whole arrangement into connection with the alternate current
supply circuit the motor will start from a state of rest; but as its speed is at first
slow, the armature and fields are supplied with an alternating current.
As the speed increases the action of the commutator gradually reduces the
alternations until the motor is traversed by a current which is continuous in direction.
This occurs for instance with a two part commutator when the alternations of the
supply current correspond in rate with the revolutions of the shaft and with multiple
part commutators in a proportionate ratio. The tendency of the motor to increase
its speed until this condition of synchronism is attained is due to the fact that the
more the rate of the alternations of the current traversing it is reduced, the more
powerful does the motor action become.
When this condition of synchronous action is reached, the motor maintains a
constant or nearly constant or synchronous rate of rotation. Any excess of speed
beyond this amount is checked by a loss of power due to the alternations setting up
inductive reactions while any diminution of speed is counteracted (within the range
of power of the motor) by the inherent tendency of the arrangement to endeavour to
attain synchronism.
The action of the synchronizing motor and commutator C¹ will be understood
from Fig. 1 and the following description. When the alternate current is switched
on it passes by way of the brushes b. b¹ and segments s, s² to the motor which at once
starts from rest, and increases in speed until synchronism is attained.
If the small segments s. s are not connected by a resistance R these segments
simply prevent the brushes short circuiting the mains m m² at the moments when
the said brushes pass across the gaps between the segments S S¹. If however, the
segments s. s¹ are connected by a resistance R, as it is advantageous they should be,
the following action occurs. When the motor has not attained synchronism a certain
amount of current will pass from the mains m m³ through the resistance R (according
to its resistance or impedance) during the short intervals when the brushes are in
contact with the segments ss, thus avoiding the opening of the circuit between the
brushes and preventing or reducing sparking of current from the alternate
current mains. When synchronism is attained the segments s. s with the attached
resistance R only become momentarily connected with the brushes and the
alternate current mains m m² during the short periods between the waves or pulsations
of the alternate current and when the said current is reduced to zero. Consequently
loss of energy in the resistance R is unimportant and is confined to the times when
synchronism is not obtained. Further, as the brushes 661 pass from the segments S S¹
to the small segments ss the terminals T T¹ of the motor become connected by means
of the brushes with the resistance R, which affords a path, momentarily, for any
current of induction from the motor winding, and thus further prevents or reduces
sparking.
It will be seen that this invention, as described for instance with reference to
Fig. 1 constitutes a synchronizing motor and commutator one of the advantages of
working such an arrangement is that besides being self starting the motor whether
doing useful work or not runs at a regular speed. "I sometimes apply the invention
simply for driving a commutator for the purpose of providing a synchronously
commuted current for any purpose for which such a current may be required. Thus
the arrangement shown in Fig. 1 may be made of small size capable only of driving the
commutators but may thus be the means of supplying a commuted current to one or

page_text: more separate motors of ordinary type (but preferably having laminated field magnets)
which may be used for doing any required amount of useful work. In such a case
the commutating motor will not be affected by any variations of load or speed of
these ordinary motors, which may then be switched on or off as required, the com-
mutating motor being conveniently permitted to run uninterruptedly. The current
commuted in this manner may be utilized for supplying any other translation
devices.
This invention may be applied to motors of the open-coil continuous current type,
and in doing so I am enabled to dispense with the collector and to use only a com-
mutator which performs the double function of commuting the current and of
supplying the commuted current to the motor winding. Fig. 2 shews snch an
arrangement, diagrammatically as applied to an open coil armature of the simplest
form having only one armature coil or pair of coils, A, a field magnet, preferably
laminated and wound with a conductor F.
The commutator is similar to that shewn at C' in Fig. 1.
One of the main commutator plates or segments S₁ is connected to one end T of
the armature coil or coils A.
The other end t of the coil or coils A is connected by a suitable rubbing contact
with one end of the field winding F the other end of F is connected by a rubbing
contact with the second commutator segment S.
It will be seen that the armature winding A and the field winding F are in series,
as in Fig. 1, and the commuted current passes through them both.
ss¹ are small segments connected and employed as described with reference to
Fig. 1.
Instead of a two-part commutator and simple open-coil armature winding the
armature and field may be wound with two or more coils or windings, connected
according to the same principle, the several plates or segments of the commutator
being made in part over-lapping, each pair of plates as S S₁ having a portion of the
armature and a portion of the field winding connected thereto as in Fig. 2.
Another part of my invention has reference to the charging of accumulators
or secondary batteries from alternate current circuits, either directly or through
transformers.
Attempts made to charge secondary batteries by means of a commuted alternate
current have been unsuccessful owing to short circuiting having taken place through
the commutator employed and to the falling to zero of the electro motive force which
has occurred between the pulsations, and this part of my invention has for its object
to obviate these obstacles to the charging of secondary batteries by a commuted
alternate current, for which purpose I employ a commutator such as that shown at (¹
in Figs. 1 and 2.
The battery terminals being connected to segments S S¹ exactly as the motor is
connected in the figure, the alternate current mains being connected to brushes bb².
I may use the same commutator C₁ for both the synchronizing motor and the
battery, or I may provide a separate commutator similar to C₁ driven by the synchro-
nizing motor in connection with the battery. And I interpose in the charging circuit
an inductional resistance, whose electromagnetic inertia converts the pulsating current
into an approximately regular one, thereby preventing the wave of electromotive
force and current from falling to zero or to such a value as to allow of a return
current or discharge from the battery. In this way I prevent destructive sparking
and waste of energy.
The armature described with reference to Fig. 1 is of the closed coil type, while
Fig. 2 refers to an open coil armature. I do not restrict myself to these arrange-
ments, which however are those which I consider most suitable for each case.
I may
use an open-coil armature in connection with the arrangement shewn in Fig. 1, and
a closed coil armature in the arrangement shewn in Fig. 2.
The figures being diagrammatic it will of course be understood that rubbing contacts
though not shewn are intended to be used where necessary to electrically connect
stationary and rotating parts.

page_text: 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 :-
1. The construction and use of a continuous current dynamo in which both the
field and the armature are arranged in the circuit of a commutator in such a manner
as to adapt the said machine to work as an alternate current motor as described and
set forth for the purposes specified.
2. An electric motor constructed with an armature, a collector, and a field of
continuous current type and with a commutator arranged to supply to the said armature
and field a current continuous in direction substantially in the manner described and
for the purpose specified.
3. In an alternate current electric motor a commutator constructed with plates or
segments connected with the terminals of the motor and with other plates or segments
connected with a suitable liquid or other resistance substantially in the manner and
for the purposes specified.
4. In an alternate current electric motor the combination and arrangement of
parts described with reference to Fig. 1 for the purposes specified.
5. In an alternate current electric motor the combination and arrangement of
parts described with reference to Fig. 2 for the purposes specified.
an inductional
6. For the purpose of charging secondary batteries the use in connection with an
alternate current circuit of a synchronizing commutator with
resistance substantially in the manner hereinabove described.
7. The use of a synchronizing motor such as hereinabove described working a
commutator for the purpose of supplying a commuted current to one or more
separate continuous current electric motors or other translation devices as set
forth.
ՄԱՆԱ
CHISHA ay or
August 2000.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.