Improvements in or relating to Mono-phase Electric Motors.
Year: 1899

page_text: Date of Application, 6th July, 1899
Complete Specification Left, 3rd Mar., 1900-Accepted, 7th Apr., 1900
Communicated from abroad by Ecoexio Cantoxo, of 15, Via degli Astalli, Rome,
in the Kingdom of Italy, Captain of Engineers.
Improvements in or relating to Mono-phase Electric Motors.
J, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 322, High Holborn, in the County of Middlesex, 6, Lord Street,
Liverpool, and 6, Bank Street, Manchester, both in the County of Lancaster,
and Lower Temple Street, Birmingham, in the County of Warwick, Civil
Engineer, do hereby declare the nature of this invention to be as follows:---
My present invention has for its object a new method for starting asynchronous
and synchronous monophasic motors which consists in drawing out the armature
and utilizing its return movement transformed into an helicoidal movement, by
means of any suitable device, for starting the motor.
For this purpose motors are constructed or existing motors are transformed
in such a manner that the armature may have a longitudinal play in the axial
direction of its shaft.
With the aid of any suitable mechanical device the armature when in posi
tion of rest is caused-to-stand more or less extracted from the space reserved to
it between the pole extensions of the induction fielil.
At the time when the current is fed to the induction system the armature
will be attracted, so as to occupy its position, by the induction field; what
1 want to perform is to transform the simple translation movement produced
by said attraction into an helicoidal movement, so that the moving system will
simultaneously advance and rotate and near its final position reach a sufficient
angular speed to give it a sufficient driving torque to keep it going.
:
Such transformation can be effected with various devices, one of which is the
following Upon the extension of the shaft carrying the armature, I key a
screw, so that when the arinature is drawn out, that is to say when the motor
is at rest, the screw will engage with a nut, or any other suitable device, such
as a sector fraction of a nut or a pin.
The length of the screw and of the nut and their relative position, must be
so predetermined that at the moment when the armature enters completely in
its place between the pole extensions, their action will cease, that is to say that
they will be completely disengaged from each other. Assuming that the nut
or pin be stationary it will be easily understood that at the time when the
current is fed to the motor, the armature attracted by the induction in order
to move along its axis will have to rotate in the direction determined by, the
screw and by proportioning its thread, which may be also decreasing if necessary,
it will be possible to obtain, that in the moment when the screw leaves the nut,
that is to say at the time when the armature is completely in place witli respect
to the induction field, the armature will have reached such an angular speed to
provide, as above stated, a sufficient driving torque to keep going.
It will also be seen that with a single screw it is possible to reverse the

page_text: movement, it being sufficient to cause the armature to go out from the oppo-
site side, with respect to the inductor, to that above referred to; in this case
when starting, the screw engaging with the nut as usual, the armature in order
to advance according to the direction of the axis of its shaft, will have to rotate
in the opposite direction to the former one.
It will again be seen that when the starting system is established, the initial
power of the driving torque. may be increased by adding to the attraction
exercised by the inductor upon the armature, when the latter is displaced, the
action of an outside additional pressure in the same direction, such as for
instance the pressure produced by means of a lever at the end of the shaft, or
by means of a suitably arranged electromagnet, the coils of which could, in
case of need, be utilized to act as a resistance for the starting movement.
In the annexed drawing:-
Figure
motor.
is a diagrammatical plan view of the iron parts of a monophasic
Figure 2 is a diagrammatical side view of same.
is the stationary part, which is generally the inductor, a is the movable
armature, which is shewn in black lines in its drawn out position so as to start
the motor through a rotatory movement of the armature in the opposite direc-
tion to that of the arrow; is the screw keyed upon the shaft: mis the handle
of the operating lever provided at its end with a pin is a fixed pin upon
which is pivoted, in a horizontal plan, the lever m, and p is the rest pin. corre-
sponding to the starting with a rotatory motion opposite to that of the arrow.
The dotted lines shew the movable armature in position for starting the motor
in the opposite direction to that above mentioned, that is to say in the direc-
tion of the arrow; shews the armature in its new position; is the screw
in its new position and the rest pin for the handle in its new, position.
It is obvious that my said invention is not limited to the construction and
arrangement of parts above described and illustrated, but that many other
different arrangements and devices may be used for accomplishing same, with-
out departing from the gist of my invention.
سيقـ
1
A T 1 1000
W. P. THOMPSON & Co..
322, High Holborn, London, W.C., Patent Agents for the Applicant.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 322, High Holborn, in the County of Middlesex, 6, Lord Street,
Liverpool, and 6, Bank Street, Manchester, both in the County of Lancaster,
and Lower Temple Street, Birmingham, in the County of Warwick, Civil
Engineer, do hereby declare the nature of this invention and in what manner
tlie same is to be performed to be particularly described and ascertained in and
by the following statement:
-
-
My present invention has for its object a new method for starting asynchronous
and synchronous monophase motors which consists in drawing out the armature
and utilizing its return movement transformed into an lielicoidal movement, by
means of any suitable device, for starting the motor.
For this purpose motors are constructed or existing motors are transformed

page_text: in such a manner that the armature may have a 'longitudinal play in the axial
direction of its shaft.
With the aid of any suitable mechanical device the armature when in posi-
tion of rest is caused to stand more or less extracted, from the space reserved to
it between the pole extensions of the induction field.,
At the time, when the current is fed to the induction system the armature
will be attracted, so as to occupy its position, by the induction field; what
I want to perform is to transform the simple translation movement produced
by said attraction into an. helicoidal movement, so that the moving system will
simultaneously advance and rotate and near its final position reach a sufficient
angular speed to give it a sufficient driving torque to keep it going.
Such transformation can be effected with various devices, one of which is tho
following Upon the extension of the shaft carrying the armature, I key a
screw; so that when the armature is drawn out, that is to say when the motor
is at rest, the screw will engage with a nut, or any other suitable device, such
as a sector fraction of a nut or a pin.
The length of the screw and of the nut and their relative position, must be
so predetermined that at the moment when the armature enters completely in
its place between the pole extensions, their action will cease, that is to say that
they will be completely disengaged from each other. Assuming that the nut
or pin be stationary it will be easily understood that at the time when the
current is fed to the motor, the armature attracted by the inductor in order
to move along its axis will have to rotate in the direction determined by the
screw and by proportioning its thread, which may be also decreasing if necessary,
it will he possible to obtain that in the moment when the screw leaves the nut,
that is to say at the time when the armature is completely in place with respect
to the induction field, the armature will have reached such an angular speed to
provide, as above stated, a sufficient driving torque to keep going.
It will also be seen that with a single screw it is possible to reverse the
movement, it being sufficient to cause the armature to go out from the oppo-
site side, with respect to the inductor, to that above referred to; in this case
when starting, the screw engaging with the nut as usual, the armature in order
to advance according to the direction of the axis of its shaft, will have to rotate
in the opposite direction to the former one.
It will again be seen that when the starting system is established, the initial
power of the driving torque may be increased by adding to the attraction
exercised by the inductor upon the armature when the latter is displaced.
In the drawing accompanying the Provisional Specification;
Figure 1 is a diagrammatical planu view of the iron parts of a monophase
motor.
Figure 2 is a diagrammatical side view of same.
.
i is the stationary part, which is generally the inductor, a is the movable
armature, which is shown in black lines in its drawn out position so as to start.
the motor through a rotatory movement of the armature in the opposite direc-
tion to that of the arrow is the screw keyed upon the shaft; m is the handle
of the operating lever provided at its end with a ping acting as a nut: pis
a fixed pin upon which is pivoted, in a horizontal plane, the lever m, and pis
the rest pin corresponding to the starting with a rotatory motion opposite to
that of the arrow.
The dotted lines show the movable armature in position for starting the motor
in the opposite direction to that above mentioned, that is to say in the direc
tion of the arrow: shows the armature in its new position; v is the screw
in its new position and the rest pin for the handle in its new position.
It is obvious that my said invention is not limited to the construction. and
arrangement of parts above described and illustrated, but that many other
different arrangements and device may be used for accomplishing same, with-
out departing from the gist of my invention,

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed. as communicated
to me by my foreign correspondent, I declare that what I claim is:-
A new method of starting asynchronous and synchronous monophase electric
motors, consisting in drawing out the armature, while in its position of rest,
from the space which it should occupy in the normal movement, and utilizing
the return movement of the armature, when attracted back, in the moment of
feeding the starting current, for producing rotation by transforming this simple
movement of translation into a helicoidal movement and thus causing a very
energetic rotary movement of the armature, in order to produce the necessary
driving torque to keep it going, substantially as set forth.
1400
W. P. THOMPSON & Co.,
322, Higli Holborn, London, W.C., Patent Agents for the Applicant.