Improvements in Electro Magnetic Devices for Producing Motion, also applicable to Dynamos and Motors.
Year: 1894

page_text: Date of Application, 24th Dec., 1894
*omplete Specification Left, 24th Sept., 1895-Accepted, 21st Dec., 1895
PROVISIONAL SPECIFICATION
Improvements in Electro Magnetic Devices for Producing Motion,
also applicable to Dynamos and Motors.
1, LLEWELYN BIROHALL ATKINSON, of 3 Whitehall Place, Westminster,
S.W. Civil Engineer, do hereby declare the nature of this invention to be as
follows-
This invention has for its object, the improvement of electro magnetic devices
for producing motion by varying the self induction of any electric appliances, and is
applicable to clectic motors whether 1otary or reciprocating, also to dynamo
electric generators.
In any electro-magnetic appliance which acts to produce motive power, by
varying the coefficient of self induction of the apparatus, during the motion, one
half of the total energy supplied goes to do mechanical work, and one half to vary
the electro kinetic energy of the system. This latter half is, in most cases of
motive power mechanism of this class, lost. Either it appears as heat, in a spark,
on breaking or opening a circuit, or it appears as heat in the conductor, when this
is short circuited, or opened with a condenser in parallel. In an apparatus
constructed in accordance with the present invention, this energy, or a large portion
of it, 18 utilized, and is made to appear as mechanical work, in the case of a motor,
In the following mannet.
The magnetic circuit, or part of it, is enclosed by two electric circuits, one of
which, A, is or inay be, permanently connected to the source of electric supply, and
one of which, B, is connected only during part of the movement to such source,
where motive power is requued.
If the first cncuit A only be closed, and the magnetic apparatus passes
through any cycle of operations, the mechanical work done, will, if it ends in
the position from which it started, be zero. If, however, the circuit B receives
electric energy only in such part of a cycle, as corresponds to an increase of
electio kinetic energy, mechanical work will be done, which may, with a
perfect machine, amount to fifty per cent. of the electric energy supplied.
Fifty per cent will however have passed into the system, as added to the electro
kinetic energy.
To utilize this portion of the energy supplied, is the object of the present
invention, which is as follows.
When the magnetic device has moved, doing mechanical work, through a certain
portion of the total movement, during which the electro kinetic energy increases,
the coil B is short circuited, A remaining in circuit. The electro-kinetic energy
will now be transformed, part into heat by maintaining a curient in the coil B, and
ait by doing work in the coil A, but the larger pait is mechanical work. In order
hat the whole energy may have run down, when that part of the movement is
eached, when the coefficient of self induction of the circuits is a maximum, the
ollowing are the proportions best adapted, in a perfect appliance, to produce this
esult.
If the total permeability of the magnetic circuit (where the position is such that
he coefficient of self induction is a maximum) be μm and at the position when the
oil B is short circuited, be μ,, and if the ampere turns on A be N, and on B are M,

page_text: then the ratio of μm to μ. is the same as the ratios of the sum of the ampere
turns N and M to the ampere turns N. By constructing electro magnetic devices
according to this invention, the energy imparted to the system appears almost
wholly as mechanical work, and sparking at breaking the cucut may be avoided
In order to maintain a uniform current in the supply circuit, a number of magnetic
devices may be arranged in sories or parallel, so that one comes into action as the
other goes out, and in order to set a current in motion in the coil B before it 15
thrown into circuit. A commutating or reversing coil may be provided, or the
coil B may itself be short circuited, during a portion of the movement.
The cucuit A may be in series with B, or separately supplied with current, or
may combine both of these arrangements with any relative pio-portioning; or, i
its place, a permanent magnet may be used. Suitable contacts, and brushes, and
contact makers are provided, to enable the coils to be short circuited and cut off at
the proper times.
This invention may be adapted to continuous curient generators or motors, in
which the variation of induction through the armature coils is produced by varying
the magnetic resistance of the magnetic circuit, passing through such coils, by the
movement of the moving part.
And this invention may be applied also to reciprocating electric engines,
independently, or in connection with, a rotating moto of the same class, which
takes cuent at that part of the stroke when the reciprocating moto is not taking
current, for the purpose of equalising the current in the supplying circuit
Dated this 24th day of December 1894.
FELL & WILDING,
1 Queen Victoria Street, E.C., Agents for the Applicant
improvements in Electro Magnetic Devices for Producing Motion,
also applicable to Dynamos and Motors.
I, LLEWELYN BIRCHALL ATKINSON, of 3 Whitehall Place. Westminster, S W.
Civil 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 :--
This invention has to its object the improvement of electro-magnetic devices
for producing motion also applicable to electic motors whether rotary or
reciprocating.
In any electro maguetic appliance which acts to produce motive power by
varying the co-efficient of self induction of the apparatus during the motion, one
half of the total energy supplied dung the motion goes to do mechanical work
and one half to vary the electio kinetic energy of the system. This latter half is
in most cases of motive power mechanism of this class, lost. Either it appears as
heat in a spark, on breaking or opening the cncuit, or it appears as heat in the
conductor, when this is short en cuited, or opened with a condense in parallel. In
an apparatus constructed in accordance with the present invention this energy, or a
large portion of it is utilized and is made to appear as mechanical work, in the case
of a motive mechanisin in the following manner
The magnetic circuit, or part of it, is enclosed by two electric circunts, one of
which is or may be permanently connected to the source of electric supply, and
one of which B is connected (to such source) only during part of the movement
in which motive power is required.
If the first circuit A only be closed, and the magnotic apparatus passes through
any cycle of operations the mechanical work doue will if it ends in the position

page_text: frain which it started be zero.
If however the encuit B receives electic energy
only in such part of a cycle, as corresponds to an increase of clectro kinetic energy,
mechanical work will be done which may with a perfect machine amount to
fifty per cent of the electric energy supplied. Fifty per cent will however have
passed into the system as added to the electio kinetic energy.
To utilize this portion of the energy supplied is the object of the present
invention, which is as follows
When the magnetic device has moved doing mechanical work, through a certain
portion of the total motion during which the electio kinetic energy increases, the
coil B is short circuited, A remaining in circuit the electro kinetic energy will now
be transformed, part into heat by maintaining a curicut in the coil B but the
larger patt into mechanical work. In order that the whole energy may have an
down when that part of the movement is reached when the co-efficient of self-
induction of the cucuits is a maximum, the following are the proportions best
adapted in a perfect appliance to produce this result.
If the total permeability of the magnetic circunt, (where the position is such that
the co-efficient of self-induction is a maximum) be fm, and at the position when the
col Bis short en cuited be μ, and if the ampere turns on A be N, aud on B are M,
then the ratio of μ to μ, is the same as the intios of the sum of the ampere turns N
and M to the ampere tuos N. By constructing electro magnetic devices
according to this invention the energy imparted to the system appears almost
wholly as mechanical work, and spanking at the breaking of the cucuit due to the
clectio kmetic momentum of the current may be avoided
'The circuit A may be in series with B or separately supplied with current or
iny combine both of these ariaugements with any relative proportioning
Or in
ite place a permanent magnet may be used. Suitable contacts, and bushes, and
contact makers are provided to enable the coils to be short circuited and cut off
at the proper time.
In oidei that my invention may be the better understood I will now proceed to
describe the same in relation to the diawings hereunto annexed reference being
had to the letters and figures marked thereon."
Figure 1 shews a typical electio magnetic mechanism of the class to which the
pre-ent invention relates, where ab are parts of an iron magnetic cu cunt with
inter venug air space adapted for iclative motion. B is an electric circuit adapted
to be energised from a soice of electric curient In the usual manner of operating
such a mechanism B being energised a and b move relatively and do mechanical
work, whilst at the same time an equal amount of energy is transferred to the
system, and on the encuit of B being broken appears as heat.
My invention consists in the application of another circuit A having N ampere
turus on it, in addition to the cicuit B of M ampere turus, this circuit A being
permanently connected to the source of supply, and in the use of these encuits aud
mechanism as follows.
A being constantly energised B is energised only dung such part of the
movement as shall bing the permeability of the magnetic circuit to a value
whore =
N
μm
N+M μm being the maximum value of the permeability obtainable
by the motion.
The circuit B is then short encuited and at the same moment disconnected from
the supply, and as the motion of a to continues, by the property of electio
magnetic circuits the electio magnetic momentum remains constant therefore
(N + M) =μm (N + M₁) where M, is the value of the ampere turns in the
coil B at the position of maximum permeability.
1
By this equation and that before given we arrive at M₁ 0 that is to say the
electro magnetic momentum and electio kinetic energy of circuit B is zero, and
the circuit B can be broken without spark.
In this explanation the electric resistance of the circuit is omitted from
consideration it being assumed that the mechanism is a perfect one, the alteration

page_text: necessitated by it being of any assumed value can be made by those versed in
the art.
The circuits A and B may be connected to the source of supply as in Figure 1
which shews a parallel or independent connection or as in Figure 1" which shows
a series or connected connection.
And in order to make my invention clear I will describe a complete cycle of
operations with each arrangement, for simplicity again neglecting the effect of the
electrical resistance of the circuit. In the case of the parallel arrangement Fig. 1A
the magnetic circuit being in the position of minimum permeability, the points d
are closed, and by the action of the E.M.F. a certain amount of electro kinetic
energy is imparted to the system, the parts of the magnetic circuit now move, the
permeability increases, and there is a further increase in the electro kinetic energy
of the cucuit, mechanical work being done until the value already described has
been reached the points fd are now opened, fe being at the same instant closed,
the magnetic circuit still continues to close to its position of maximum permeability
as before described, mechanical work being done, at the expense of the electio
kinetic energy of the system, until having reached its minimum value, the
points are opened without spark and the magnetic circuit moves to its original
position. During his cycle, work is done by the circuit A, as the permeability
increases, and an equal amount is done on the circuit A as the permeability
decreases, the result during the cyclo being zero, the circuit A may therefore be
replaced by a permanent magnet as in Figure 2 where C is a permanent magnet.
In order to avoid sparking between d due not to electro-magnetic energy in the
circuit which must run down, but to the passage of an aic across heated air, the
points d. f. may bo saparated under oil, or in a inaguetic field, or under the action of
an air blast, this however is not a source of waste of power.
In the case of the series arrangement Fig. 1 the cycle is a little more complex,
due to the necessity of starting a current in the coil B before it is placed in
circuit.
The cycle will therefore commence with the magnetic circuit in the position of
maximum permeability, the points h. hl. m. are both open and the circuit A closed.
The magnetic circuit opens, but before the point of mummun permeability is
reached hk. Im are both closed thus short circuiting B. This staits a curent, and
when the value is reached, which is the same as the current in A l. m. is opened.
The permeability of the magnetic circuit having now reached its minimum value
the magnetic encuit comniences to close, till the point before described is reached
at which B is short cn cuited by closing 1. m the magnetic circuit then further
closing till the permeability reaches its maximum value when the current in B is
zero and h. k. is then broken without a spark and the cycle is complete.
Electio magnetic organs operating by these processes may be combined to form
reciprocating or rotary motois. Thus two such mechanisins as are described, when
combined form a reciprocating engine, having an efficiency comparable with that
given by ordinary continuous current motors, and which may be operated without
spanking at the contacts.
In order to maintain a uniform current in the supply circuit a number of magnetic
devices may be allauged in series or parallel so that one comes into action as the
other goes out, and where the series connection is adopted in order to set a current
in motion in the coil B before it is thrown into circuit, a commutating or reversing
coil may be provided, or the coil B may itself be short circuited during a portion
of the movement, and in this manner this invention may be applied to continuous
ourrent motors of that class in which the variation of induction through the armaturo
coils is produced by varying the magnetic resistance of the magnetic circuit pressing
through such coils by the movement of the moving part.
And this invention may be applied also to reciprocating electric engines
independently, or in connection with a rotating motor of the same class which takes
ourient at that part of the stroke when the reciprocating motor is not taking
current, for the purpose of equalising the curent in the supplying circuit.

page_text: By combining several of such organs so that one of them is always taking current
from the supply, rotatory motors inay be constructed, having no moving wires aud
with simple coil armatures, and of high efficiency. They may be in general con-
struction of the form known as Fioment's motor but having laminated cores to the
magnets and laminated armatures, and fitted with evolving contact plates and
brushes, to effect the circuit making and breaking operations herein described.
For this purpose generally the series connection is the best adapted. Such a
moto is shewn diagramatically in Figure 3 whore 1, 2, 3, 4 are magnets of
laminated iron with windings A B as described
The revolving part consists of a wheel cartying armatures of laminated iron, and
so aanged as to act successively in conjunction with the magnet 1, 2, 3, 4.
The ends of the coil B of these magnets are connected to bi ushes and these press
on a revolving contact plate, the organization of which may be varied, but so
arranged as to successively cairy out the operations of making, short circuiting and
breaking the cucuits of these coils.
The coils A are permanently connected together and as shewn are in series with
the extreme coils of the B coils and with the source of supply.
By omitting magnets 1 and 3 say, and replacing their circuits by the cucuits of
two orgaus as Figure 1 forming a reciprocating motor, ruuning synchronously with
the evolving motor, the current from the source of supply may be maintained
constant, alternate current impulses going to the reciprocating and to the revolving
motois
Electro magnetic engines thus constincted may be termed electro dynamic
ongines because pait at least of the work done on the moving part is done by
maintaining the client against the E M.F. of electio dynamic induction due to the
motion.
My invention however enables me to construct a new class of electric engine,
which call an electio kinetic engine, and which I will now describe
Refering to the arrangement of parallel connection shewn in Figure 1 suppose
the proportioning of the coils A B is such that in the position of minimum
permeability pa
a (N+M) = m (N + M₁)
then is the position at which the supply must be cut off and the coil B must be
short en cuited. In this case the whole mechanical work douc, is due to the electio
kinetic energy stored in the system, and the applied E M F. only acts to supply
clectio kinetic energy, before the motion commences The amount of electio kinetic
energy supplied depends on the time during which the E.M.F. is applied, and by
moving the contact brushes relatively to the plates the time may be mado constant
respective of the velocity of motion
By this arrangement it follows therefore that such an electro kinetic engine, can
be un from a constant source of E M.F. at any speed without resistance, and for a
given amount of work per revolution, taking an average current proportioned to the
speed, or it can be run at a constant speed on circuits of varying E M.F. taking for
the same work per revolution, the same average curent, by varying the time during
which the E.M F. is applied
To maintam the speed constant with varying work per revolution a governor must
be provided to vary the time during which the E.M F. is applied
These conditions of course only apply within the limits of work that the motor
Is capable of performing, but it can be shewn that such an electro kinetic engine,
can give a greater output for a given weight of engine, than any possible electro
dynamic engine, of the same efficiency.
In the same way reciprocating engines may be constructed in which the energy
is imparted before the motion commences in each reciprocation.
Such motors may also be used as meters or measurers of electric energy, by
connecting the circuit for a definite time to the source of E.M.F. or current, and
then by allowing the motion to take place, the amount of motion will be proportioned

page_text: to the electro kinetic energy imparted to the system in manuer that will be
understood by those skilled in the ait.
Having now particularly described and ascertained the nature of my said inven-
tion and in what mauner the same is to be performed I declare that what I
claim is :-
In an electro magnetic mechanism for the production of motion by the variation
of the permeability of the magnetic circuit, the combination of a magnetic circunt
of vanable permeability, with one coil adapted to be constantly energised, and
another coil adapted to be energised during a specific part of the motion and to be
short circuited and disconnected from the source of supply during another specific
part of the motion, substantially as descubed.
2nd. In an electio maguetic mechanism as claimed in Claim 1 the combination
of a magnetic circuit of variable permeability, with a constantly energised coil,
a coil energised duing part of a cycle of operation from source of supply
and contact makers adapted to carry out the cycle of operations, substantially as
described and illustrated in Figure 1 of the accompanying drawing
3rd. In an electro magnetic mechanism as clauned in Claim 1 the combination of
a magnetic circuit of variable permeability, with a constantly energised coil, a coil
energised dining part of a cycle of opriation from source of supply and contact
makers adapted to carry out the cycle of operations, substantially as descubed and
illustrated in Figure 1 of the accompanying diawing
4th. In an electio magnetic mechanism for the production of motion by the
variation of the permeability of the magnetic circuit, the combination of n
permanent magnet with a coil adapted to be cnergised during a specific part of the
motion and to be short circuited and disconnected from the energising current
during another specific part of the motion substantially as described
5th A rotary or reciprocating electric engine constructed with the electro-
magnetic combinations as claimed in Clains 1, 2, 3 or 4 as a means of obtaining
motive power, substantially as described.
6th. An electio magnetic engine constructed substantially in accordance with
Figure 3 of the accompanying drawing.
7th. An electro magnetic engine having the combination of parts claimed in
Claims 1 and 2, proportioned to form an electio kinetic engine substantially as
described.
8th. The combination of a reciprocating engine as described with a rotary engine
as descubed, as a means of maintaining constant the current from the source of
supply, substantially as descubed.
9th. The construction of electric meters or measuring apparatus having as the
ineaus of measuring a motive mechanism whose motion is dependent on the electro
kinetic energy imparted to the system by the source to be measured, substantially
as described
Dated thus 24th day of September 1895.
FELL & WILDING,
1 Queen Victoria Sticet, London, E.C., Agents for the Applicant.