Improvements connected with Electric Motors and Elevators.
Year: 1891

page_text: Date of Application, 18th Sept., 1891
Complete Specification Lett. 20th May, 1892-Accepted, 9th July, 1892
PROVISIONAL SPECIFICATION.
Improvements connected with Electric Motors and Elevators.
A communication from abroad by OTIS BROTHERS & Co., of 38, Park Row,
New York, in the United States of America, Manufacturers.
We, AMERICAN ELEVATOR COMPANY a body incorporated under the laws of
the State of Illinois one of the United States of America of 4, Queen Victoria
Street in the City of London do hereby declare the nature of this invention
to be as follows:-
This invention relates generally to the utilization of electricity in operating
motors for the purpose of driving machinery of various classes, and more particularly
It has for its object to over-
to the use of electric motors for operating elevators.
come some of the difficulties or bad effects experienced in starting the motor with
its load, and to prevent the accidental displacement of the switching apparatus, and
to provide means whereby the operator in the cage may be sure that the switch is
in the proper position, so that the apparatus can be left with safety. To these ends,
the invention consists in the features of construction and arrangement of devices,
substantially as hereinafter set forth.
Referring to the accompanying drawings,
Figure is a general view of an electric motor, and its connections with an
elevator;
Figure 2 is a plan view of a portion of the devices, showing the locking
mechanism for the switch;
Figure 3 is a detail view of a modification of the same;
Figure 4 is an enlarged diagrammatic view of the circuits of the motor, showing
one einbodiment of the invention; and
Figure 5 is a similar view showing another arrangement of circuits.
The invention is shown as applied to an electric motor of a well known type. . It
is well known that to start a motor connected to drive an elevator, or other
machinery, from a state of rest requires an excessive amount of current; sometimes
nearly double the quantity of current that is required to maintain the motor in
When the current is turned
operation after the elevator or machinery is in motion.
on to start a motor under these conditions, the pressure in the main line drops to a
greater or less extent, especially when the generator plant furnishing the current is
of limited capacity, and where the regulation of such generators is not of the very
highest efficiency to compensate for such drop.
When the motor used is what is known as a shunt wound motor, the drop of
pressure weakens the field of the motor in such a way that the motor will not start
with a full load on. In order to get the strongest pull or torque at the moment of
starting with such a motor, it is necessary to have a strong field, and many turns or
coils on the armature, and for this reason, according to this invention it is preferred
to use motor with a larger number of armature coils than is necessary to
operate the elevator or other machinery after it has started, and is running at
normal speed.
motor
It has been found in some instances, that it is desirable to provide the armature
with double the number of ampere turns or coils, that is necessary for the normal
speed In other words, according to the present invention there is used an
armature wound so as to be adapted to utilize a 500 volt current in a
otherwise adapted to utilize a 2:0 volt current, or any other relative arrangement
of the armature coils in excess of the normal arrangement. Such a motor would,
with the same strength of field, run at about half the speed, as if the regular and
usual number of armature turns were used, and it would also start the same load

page_text: with about half the current. Furthermore, the starting of such a motor with its
load will cause very little drop in the circuit of a plant having even a limited
generator.
After the motor is started with its load, the strength of the field magnet coils is
weakened so that then the motor will run at its normal speed, the same as if the
armature had the usual proportion of turns. for the reduced strength of the field
circuit. This is accomplished automatically by different means, one being by
throwing a resistance into the field magnet circuit.
Another way of accomplishing this object, consists in the arrangement of the
field magnet coils at starting, and when running under its normal load. Thus ou
starting, the field magnet coils may be arranged in parallel sections, and after-
wards when the motor has attained its speed, these sections may be connected in
series. This will enable the motor to start with a full field even at a greatly
reduced voltage, as the resistance of the field when normally running, is double
that when the field is excited with the sections in parallel. This last arrangement,
while it is not as advantageous in some respects as the first arrangement, still
gives the full field strength of the shunt motor when the voltage has fallen by the
excessive current used in starting.
It is desirable in the operation of electric motors, especially in connection with
elevators, that every precaution should be taken to prevent accidents, and to insure
the correct and safe running of the elevator apparatus, and means are herein
accordingly provided whereby the switch device controlling the circuit of the
motor may be automatically locked in position against accidental displacement,
but which lock is under the control of the operator.
It is not deemed necessary to describe in detail the operation of this machine,
us it is well understood by those skilled in the art, it being sufficient to say that
A is the winding drum upon which the rope B is wound and unwound to raise and
lower the car B', the rope passing over suitable sheaves B². The drum A is
supported upon a shaft A', which is mounted in suitable bearings on the base
plate A², and this drum is operated for instance, by a worm wheel on the shaft C,
meshing with a suitable worm gear on the shaft A¹. This shaft C is driven by an
electric motor D, the armature D' of which is fixed to the shaft C.
The current supplied to the electric motor, which motor may be of any desired
type, but is preferably a shunt wound motor of the Eickemeyer type, is controlled
by a suitable switch device S, whereby it may be started, stopped, reversed and
otherwise controlled in a manner more fully hereinafter set forth. This switch
device S, is shown as operated by a segmental lever arm E, which in turn is
connected to a sliding rod F, and this in turn is connected by a segmental arm G
to a pinion G' on the shaft A', and this pinion is adapted to be operated from the
car or other position by means of the hand rope H, a lever, or other well known
mechanical or electrical device adapted for the purpose.
The switch device is arranged so that the current may be turned on to the motor
in such manner as to cause the armature of the motor to rotate in the desired
direction, and to avoid the danger of injuring or burning the motor, the current is
first admitted to the field coils to excite the field magnet and is then gradually
admitted to the armature circuit, until the whole current in the circuit is passing
through the machine, resistance devices being connected to the switch to prevent
the current passing with its full force directly to the armature. If, for instance,
the armature should not turn under the current from any cause, as an over-loading
or otherwise, there is still liability of burning or injuring the armature coils, and to
guard against this, a self-acting safety device is provided by which a certain
external resistance is included in the armature circuit as long as the current which
the armature would otherwise receive is beyond the normal or safety limit, but as
the motor starts, and the counter electro-motor force of the armature increases, this
external resistance is automatically reduced or removed from the armature circuit,
and when the motor is stopped, this external resistance is automatically included in
the armature circuit, and the current gradually turned off.

page_text: Thus in the diagram, the main line circuit terminates at the binding posts P, N.
and from these posts are conductors leading to the plates 1, 2, of the switch S.
The switch is provided with a switch arm S', having insulated conductors plates 3, 4,
at its ends, the arm being pivoted on a shaft S2 and adapted to be moved by the
connections between the shaft and the hand rope or equivalent device. One of
the plates 1, of the switch is connected to one terminal 5 of the field coils of the
motor D, and the other plate 2, is connected to the other terminal 6 of the field
coils of the motor. The segmental plate 7 of the switch is connected to one of the
brushes 8 of the armature of the motor, and the other brush 9 is connected to one
of a series of contact plates 10 of the switch which are connected together with
interposed resistances 11 between the plates.
Interposed in the armature circuit is a solenoid 12, the core 13 of which bears on
a series of contact plates 14, connected together by resistances 15. and this core is
under the control of a weighted lever 16, which normally tends to withdraw the
core from the solenoid; so that it will rest upon the upper plate 14. This weighted
lever, however, is controlled by a cam 37, preferably on the shaft S2 of the switch
lever, and this cam is so shaped that when the switch is in its normal position, and
the current cut out, and until the switch is turned to either side to contact with one
of the extreme plates 10, the lever 16 is held in the position shown best in Figure 4,
with the core to its fullest extent within the coils of the solenoid. When the
switch lever is turned to the extreme position, the cam allows the lever 16 to move
under the influence of the weight, if not otherwise controlled, so as to cause the
core 13 to bear on the uppermost contact plate 14, and thereby cut out of the
armature circuit, the resistance 15.
When, however, on turning the switch, and for some reason the motor does not
start, and too much current would flow through the armature coils, the coils of the
solenoid 12 are energized to such an extent as to hold its core in the position
shown in Figure 4, retaining the resistance 15 in the armature circuit, and not
until the, motor starts, and produces sufficient counter-electro motor force to offer a
proper resistance to the circuit through the armature, will the attractive force of
the solenoid be reduced sufficiently to allow the weighted lever to move its core
to withdraw the resistance 15 from its circuit.
It will thus be seen that the cam will insure the resistance 15 being included in
the circuit, until the full current is turned on to the motor, and then if this
current from any cause is too strong to safely pass through the coils of the
armature, the resistance 15 will be retained in the armature circuit, but when
the current through the armature is of proper strength, the resistance will be
automatically cut out by means of the weighted lever, and the motor run under
normal conditions, as far as the armature is concerned.
In order to utilize the proper amount of current to the best advantage in
starting the motor, there is interposed in the field magnet circuit, a resistance, or
the current is changed through the coils of the field magnet as before indicated.
To do the first, there is interposed in the field magnet circuit, a resistance
device 36, and the terminals thereof are connected to the contact plates 17, 18.
There is also attached preferably to the core 13 of the solenoid, but insulated
therefrom a contact brush 19, which normally short circuits the plates 17 and 18,
cutting out of the field magnet circuit, the resistance coil 36. When however, the
motor has started under normal conditions, and the resistance of the armature is
automatically cut out, the contact plate 19, is carried upward by the solenoid
core 13, until it passes beyond the contact 18, and this puts the resistance 36 into
the field magnet circuit, and the motor runs with the proper field of force to
operate the motor with its load.
In order to trace the circuits definitely, the parts will be assumed to be in the
position indicated in full lines in Figure 4. The switch arm S' is gradually turned
to the left as indicated in dotted lines, and as soon as the contact plate 3 passes on
to the first plate 10 and completes the circuit between the plate 1 and one of the
contact plates 10, the armature current passes through said contact plate, and the

page_text: 1
resistance 11, to the opposite contact plate 10, and thence through the contact
plate 14, and resistances 15, the core 13; the solenoid 12 to the brush 9, through the
coils of the armature to the brush 8, thence to the plate 7, and by the contact
plate 4 of the switch arm to the plate 2, and out at the binding post N. As the
switch arm S¹ moves farther, the resistances 11 are gradually cut out of the
armature circuit, and the cam 37 is rotated, so that its slot comes to a position to
allow the weighted lever 16 to operate. If, however, the current is too strong, the
solenoid will hold its core in the position shown, but when the current becomes
normal, the solenoid core is moved under the influence of the weight, and the
resistance 15 cut out, and the short circuit of the resistance 36 which has been cut
out of the field magnet circuit is broken and the resistance thrown in the field
magnet circuit.
From this arrangement it will be seen that not only can the motor be started
under a heavy load, but that it can be run at different speeds under varying loads.
Thus when the motor is started under any conditions, all the armature resistances
are in the circuit, and the field resistance is cut out of circuit. When the motor
has started and sufficient counter electro motive force is generated, the armature
resistance 15 is cut out, and if the load is light, the field resistance 36 is cut into
circuit, and the motor will run rapidly with its light load. If, however, the load is
heavy, and the current through the motor increases, the solenoid will draw its core
downward sufficiently to close the short circuit of the resistance 36, and this will
reduce the amount of current through the motor, which will run more slowly, and
continue so unless the current gets excessive when the resistance 15 will gradually
be included in the armature circuit.
In the modified arrangement shown in Figure 5, the switch and armature circuits
are the same as in Figure 4, but the field magnet coils are wound in sections, a
loop being taken from the coils 20, 21, and connected to the contact plates 22, 23,
respectively, and the terminals of the field magnet coils 5 and are also respectively
connected to the contact plates 24 and 25. Attached to the solenoid core 13, is an.
insulating bar 26, carrying circuit closers 27, 28, and under the starting conditions,"
the contact closer 27, completes the circuit between the contact plates 25 and 22,
and the circuit closer 28 completes the circuit between the contact plates 23 and 24.
Under these conditions, the field magnet circuit at the point 5 divides, a portion
passing through part of the coils of the field magnet out at the post 20, thence to,
the contact plate 22 by the circuit closer 27 to the contact piece 25, and out at the
binding post 6 while the other portion of the current passes from the binding
post 5, to the contact 24, thence by the circuit closer 28 to the contact 23 to the
post 21, and through the remaining coils of the field magnets, and out at the post 6,
thus putting two portions of the coils of the field magnet in parallel.
When, however, the motor has started, and is running normally, the solenoid"
core 13 rises under the influence of the weighted lever 16, and the circuit closers
move off their respective contacts, and the circuit closer 27 closes the circuit
between the contacts 22 and 23, and under these conditions the current through the
field magnet enters at the post 5, passes through the portion of the coils to the
post 20, thence to the contact plate 22, by the circuit closer 27 to contact plate 23,
thence to the post 21, and through the remaining coils of the field magnets to the
post 6, and to line, putting the coils of the field magnet in series, so that the motor
will run properly under its load.
As shown in the drawing, the switch arm S is in its normal position with the
circuits broken, so that no current passes through the switch and to the motor,
but when the band rope H is operated, the shipper bar F is moved through the
medium of the segmental lever G to operate the segmental lever E, and thence
the switch arm. The segmental lever E is shown as connected to the shipper
bar through the medium of springs e between the free end of the lever and lugs
or supports on the shipper bar against which the springs bear. These springs
are preferably of such a strength and resiliency, that under ordinary conditions,
the segmental lever will be moved in accordance with the movements of the

page_text: shipper bar, but if any obstructions or hinderance to the movement of the
segmental lever occurs, they will be compressed to a greater or less extent before
the lever is operated.
To secure the switch arm in its normal position with a dead brake of the
circuit, there is provided some suitable locking device, and while this may be
variously constructed, it is here shown as a simple pawl el which is normally under
the stress of a spring e, and this pawl engages a notch in the stationary bar F
secured to the framework of the device, and this holds the brush in position until
the locking device is released. Various ways of releasing the device may be
adopted, as illustrated the shipper bar F is provided with a recess f¹ having
inclined sides which engage the extension of the pawl e', and lift it out of the
notch in the bar F'.
r
The parts being in the position shown in Figure 1, and the operator pulling the
hand rope H to start the engine will move the shipper F, and as the segmental
lever Eis locked, the spring e will be compressed, and require more than ordinary
force or pull to be exerted upon the hand rope to move the shipper bar.
As soon
as the bar has moved sufficiently to cause the incline of the notch in the bar to
raise the pawl ', and unlock the segmental lever, the lever will be operated freely
to control the circuit, and the springs will maintain the lever in its normal relation
to the shipper bar throughout its movement, and it will move freely, in harmony
with the movements of the bar. When, however, the elevator is stopped, and the
switch is moved into its normal position (or in any other desired position if the
lock is correspondingly arranged) the lever will become locked, and require
the extra force to move it from its locked position, and the operator in the car
will readily understand from the feel of the rope, or the extra force required to
leave it, that the switch arm is in the proper position, and can move the elevator
with the assurance that everything is correctly arranged, and in position to leave
with safety.
The same general construction and arrangement of parts may be carried out by
electrical means instead of mechanical, as shown in Figure 3, wherein the shipper
bar F supports the coils of a solenoid m on either side of the segmental lever E.
Mounted on this lever is a core n extending on through either side into the coils of
the solenoids. The coils of the solenoids may be connected in the main circuit of
the motor, or in a separate local circuit, the latter being indicated for convenience,
and the terminals are connected by a flexible conductor or brush y, bearing on an
extended contact m', so that the coils of the solenoid are in circuit whatever may
be the position of the shipper bar.
The shipper bar is preferably provided with studs a on either side of the
segmental lever, which while allowing a certain freedom of movement, or backlash
so to speak, between the shipper bar and the lever, will insure the lever being
moved when the shipper bar has moved a certain extent.
The pawl c attached to the segmental lever is in this instance made of
magnetic material, or has a portion of it so made, and takes into the notch in the
stationary bar F'. Above the pawl is arranged a magnet y the coils of which are
in a branch of the electric circuit, one end being connected to the contact which
normally rests on an insulated portion of the shipper bar, but which is adapted to
make contact with the contacts at either side of the insulated portion.
From this arrangement it will be seen that the parts are normally locked, and
the operator moving the shipper bar, the core of the solenoids will pass into the
coils thereof against the tendency of these coils to maintain the core in
equilibrium between them, but as soon as the contact t bears upon either of the
contacts s, the branch circuit is completed, and a portion of the current flowing
through the magnet g, energizes the same, and this raises the pawle out of the
notch in the stationary bar F, and the attraction of the core of the solenoid
causes the segmental lever to assume its normal position between the coils of the
solenoid, and the switch is then moved in accordance with the movement of the
shipper bar. It will be understood that the operator on the car has not only to

page_text: move the shipper bar, but to overcome the tendency of the core of the solenoid to
maintain its normal position, and this will require an extra force which the
operator will understand from the feel of the rope to indicate that the segmental
lever with its connecting switch controlling the motor is, in its normal position.
Dated the 18th day of September 1891.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements connected with Electric Motors and Elevators.
A communication from abroad by OTIS BROTHERS & Co., of 38, Park Row,
New York, in the United States of America, Manufacturers.
We, AMERICAN ELEVATOR COMPANY, a body incorporated under the laws of
the State of Illinois one of the United States of America of 4 Queen Victoria
Street in the City of London, 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 relates generally to the utilization of electricity in operating
motors for the purpose of driving machinery of various classes, and more particularly
to the use of electric motors for operating elevators. It has for its object to over-
come some of the difficulties or bad effects experienced in starting the motor with
its load, and to prevent the accidental displacement of the switching apparatus,
and to provide means whereby the operator in the cage may be sure that the
switch is in the proper position, so that the apparatus can be left with safety.
To these ends, the invention consists in the features of construction and arrange-
ment of devices, substantially as hereinafter set forth.
•
Referring to the drawings filed with our Provisional Specification,
Fig. 1 is a general view of an electric motor, and its connections with an
elevator :
Fig. 2 is a plan view of a portion of the devices, shewing the locking mechanism
for the switch;
Fig. 3 is a detail view of a modification of the same;
Fig. 4 is an enlarged diagrammatic view of the circuits of the motor, shewing
one embodiment of the invention; and
Fig. 5 is a similar view shewing another arrangement of circuits.
The invention is shewn as applied to, an electric motor of a well known type. It is
well known that to start a motor connected to drive an elevator, or other machinery,
from a state of rest requires an excessive amount of current; sometimes nearly
double the quantity of current that is required to maintain the motor in operation
after the elevator or machinery is in motion. When the current is turned on
to start a motor under these conditions, the pressure in the main line drops to
a greater or less extent, especially when the generator plant furnishing the
current is of limited capacity, and where the regulation of such generators is not
of the very highest efficiency to compensate for such drop.
When the motor used is what is known as a shunt wound motor, the drop of
pressure weakens the field of the motor in such a way that the motor will not start
with a full load on. In order to get the strongest pull or torque at the moment of
starting with such a motor, it is necessary to have a strong field, and many turns or
coils on the armature, and for this reason, according to this invention it is preferred
to use a motor with a larger number of armature coils than is necessary to operate
the elevator or other machinery after it has started, and is running at normal
speed.
It has been found in some instances, .that it is desirable to provide the armature
with double the number of ampère turns or coils, that is necessary for the normal

page_text: speed. In other words, according to the present invention there is used an armature
wound so as to be adapted to utilize a 500 volt current in a motor otherwise adapted
to utilize a 250 volt current, or any other relative arrangement of the armature
coils in excess of the normal arrangement. Such a motor would, with the same
strength of field, run at about half the speed, as if the regular and usual number of
armature turns were used, and it would also start the same load with about half the
current. Furthermore, the starting of such a motor with its load will cause very
little drop in the circuit of a plant having even a limited generator.
After the motor is started with its load, the strength of the field magnet coils, is
weakened, so that then the motor will run at its norinal speed, the same as if the
armature had the usual. proportion of turns for the reduced strength of the field
circuit. This is accomplished automatically by different means, one being by
throwing a resistance into the field maguet circuit.
Another way of accomplishing this object, consists in the arrangement of the
field magnet coils at starting, and when running under its normal load. Thus ou
starting, the field magnet coils may be arranged in parallel sections, and afterwards
when the motor has attained its speed, these sections may be connected in series.
This will enable the motor to start with a full field even at a greatly reduced
voltage, as the resistance of the field when normally running, is double that when
the field is excited with the sections in parallel. This last arrangement, while it
is not as advantageous in some respects as the first arrangement, still gives the full
field strength of the shunt motor when the voltage has fallen by the excessive
current used in starting.
It is desirable in the operation of electric motors, especially in connection with
elevators, that every precaution should be taken to prevent accidents, and to insure
the correct and safe running of the elevator apparatus, and means are herein
accordingly provided whereby the switch device controlling the circuit of the motor
may be automatically locked in position against accidental displacement, but which
lock is under the control of the operator.
It is not deemed necessary to describe in detail the operation of this machine, as
it is well understood by those skilled in the art, it being, sufficient to say that A is
the winding drum upon which the rope B is wound and unwound to raise and lower
the car B', the rope passing over suitable sheaves B'. The drum A is supported
upon a shaft A', which is mounted in suitable bearings on the base plate A³, and
this drum is operated for instance, by a worm wheel on the shaft C, ineshing with
a suitable worm gear on the shaft A¹. This shaft C is driven by an electric motor D,
the armature D' of which is fixed to the shaft C.
The current supplied to the electric motor, which motor may be of any desired
type, but is preferably a shunt wound motor of the Eickemeyer type, is controlled
by a suitable switch device S, whereby it may be started, stopped, reversed and
otherwise controlled in a manner more fully hereinafter set forth. This switch..
device S, is shewn as operated by a segmental lever arm E, which in turn is
connected to a sliding rod F, and this in turn is connected by a segmental arm G
to a pinion G¹ on the shaft A', and this pinion is adapted to be operated from the
car or other position by means of the hand rope H, a lever, or other well known
mechanical or electrical device adapted for the purpose.
The switch device is arranged so that the current may be turned on to the motor
in such manner as to cause the armature of the motor to rotate in the desired
direction, and to avoid the danger of injuring or burning the motor, the current is
first admitted to the field coils to excite the field magnet and is then gradually
admitted to the armature circuit, until the whole current in the circuit is passing
through the machine, resistance devices being connected to the switch to prevent
the current passing with its full force directly to the armature. If, for instance,
the armature should not turn under the current from any cause, as an over loading
or otherwise, there is still liability of burning or injuring the armature coils, and to
guard against this, a self-acting safety device is provided by which a certain
external resistance is included in the armature circuit as long as the current

page_text: which the armature would otherwise receive is beyond the normal or safety
limit, but as the motor starts, and the counter electro motor force of the
armature increases, this external resistance is automatically reduced or removed
from the armature circuit, and when the motor is stopped, this external resistance
is automatically included in the armature circuit, and the current gradually
turned off.
Thus in the diagram, the main line circuit terminates at the binding posts P, N,
and from these posts are conductors leading to the plates 1, 2, of the switch S.
The switch is provided with a switch arm S', having insulated conductors
plates 3, 4, at its ends, the arm being pivoted on a shaft S2 and adapted to be
moved by the connections between the shaft and the hand rope or equivalent
device. One of the plates 1, of the switch is connected to one terminal of the
field coils of the motor D, and the other plate 2, is connected to the other terminal 6
of the field coils of the motor. The segmental plate 7 of the switch is connected
to one of the brushes 8 of the armature of the motor, and the other brush 9 is
connected to one of a series of contact plates 10. of the switch which are connected
together with interposed resistances. 11 between the plates.
.)
Interposed in the armature circuit is a solenoid 12, the core 13 of which bears on
a series of contact plates 14, connected together by resistances 15, and this core is
under the control of a weighted lever 16, which normally tends to withdraw the
core from the solenoid; so that it will rest upon the upper plate 14. This weighted
lever, however, is controlled by a cam 37 preferably on the shaft S of the switch
lever, and this cam is so shaped that when the switch is in its normal position, and
the current cut out, and until the switch is turned to either side to contact with one
of the extreme plates 10, the lever 16 is held in the position shewn best in Fig. 4,
with the core to its fullest extent within the coils of the solenoid. When the
switch lever is turned to the extreme position, the cam allows the lever 16 to move
under the influence of the weight, if not otherwise controlled, so as to cause the
core 13 to bear on the uppermost contact plate 14, and thereby cut out of the
armature circuit, the resistance 15.
When, however, on turning the switch, and for some reason the motor does not
start, and too much current would flow through the armature coils, the coils of the
solenoid 12 are energized to such an extent as to hold its core in the position shewn
in Fig. 4 retaining the resistance 15 in the armature circuit, and not until the motor
starts, and produces sufficient counter-electro motor force to offer a proper resistance
to the circuit through the armature, will the attractive force of the solenoid .be
reduced sufficiently to allow the weighted lever to move its core to withdraw the
resistance 15, from its circuit..
It will thus be seen that the cam will insure the resistance 15 being included in
the circuit, until the full current is turned on to the motor, and then if this current
from any cause is too strong to safely pass through the coils of the armature, the
resistance 15, will be retained in the armature circuit, but when the current through
the armature is of proper strength, the resistance will be automatically cut out by
means of the weighted lever, and the motor run under normal conditions, as far
as the armature is concerned.
In order to utilize the proper amount of current to the best advantage in starting
the motor, there is interposed in the field magnet circuit, a resistance, or the current
is changed through the coils of the field magnet as before indicated. To do the
first, there is interposed in the field magnet circuit, a resistance device 36, and the
terminals thereof are connected to the contact plates 17, 18. There is also attached
preferably to the core 13 of the solenoid, but insulate therefrom a contact, brush 19,
which normally short circuits the plates 17 and 18, cutting out of the field magnet,
circuit, the resistance coil 36. When however, the motor has started under normal
conditions, and the resistance of the armature is automatically cut out, the contact
plate 19, is carried upward by the solenoid core 13, until it passes beyond the
contact. 18, and this puts the resistance 36 into the field magnet circuit, and, the
motor runs with the proper field of force to operate the motor with its load.

page_text: 'on to
In order to trace the circuits definitely, the parts will be assumed to be in the
position indicated in full lines in Fig. 4. The switch arm S' is gradually turned to
the left as indicated in dotted lines, and as soon as the contact plate 3 passes on
the first plate 10 and completes the circuit between the plate 1 and one of the
contact plates 10, the armature current passes through said contact plate, and
the resistance 11, to the opposite contact plate 10, and thence through the
contact plate 14, and resistances 15, the core 13, the solenoid 12 to the brush 9,
through the coils of the armature to the brush 8, thence to the plate 7, and
by the contact plate 4 of the switch arm to the plate 2, and out at the binding
post N. As the switch arm S¹ moves farther, the resistances 11 are gradually cut
out of the armature circuit, and the cam 37 is rotated, so that the slot comes to a
position to allow the weighted lever 16 to operate. If, however, the current is too
strong, the solenoid will hold its core in the position shewn, but when the current
becomes normal, the solenoid core is moved under the influence of the weight, and
the resistances 15, cut out, and the short circuit of the resistance 36 which has been
cut out of the field magnet circuit is broken and the resistance thrown in the field
magnet circuit.
Fr
From this arrangement it will be seen that not only can the motor be started
under a heavy load, but that it can be run at different speeds under varying loads.
Thus when the motor is started under any conditions, all the armature resistances
are in the circuit, and the field resistance is cut out of circuit. When the motor
has started and sufficient counter electro motive force is generated, the armature
resistance 15 is cut out, and if the load is light, the field resistance 36 is cut into
circuit, and the motor will run rapidly with its light load. If, however, the load is
heavy, and the current through the motor increases, the solenoid will draw its core
downward sufficiently to close the short circuit of the resistance 36, and this will
reduce the amount of current through the motor, which will run more slowly, and
continue so unless the current gets excessive when the resistance 15 will gradually
be included in the armature circuit.
In the modified arrangement shewn in Fig. 5, the switch and armature circuits
are the same as in Figure 4, but the field magnet coils are wound in sections, a loop
being taken from the coils 20, 21, and connected to the contact plates 22, 23,
respectively, and the terminals of the field magnet coils 5 and 6 are also respectively
connected to the contact plates 24 and 20. Attached to the solenoid core 13, is an
insulating bar 26, carrying circuit closers 27, 28, and under the starting conditions,
the contact closer 27, completes the circuit between the contact plates 25 and 22,
and the circuit closer 28 completes the circuit between the contact plates 23 and 24.
Under these conditions, the field magnet circuit at the point 5 divides, a portion
passing through part of the coils of the field magnet out at the post 20, thence to
the contact plate 22 by the circuit closer 27 to the contact piece 25, and out at the
binding post 6; while the other portion of the current passes from the binding
post 5, to the contact 24, thence by the circuit closer 28 to the contact 23 to the
post 21, and through the remaining coils of the field magnets, and out at the post 6,
thus putting two portions of the coils of the field magnet in parallel.
When however, the motor has started, and is running normally, the solenoid
core 13 rises under the influence of the weighted lever 16, and the circuit closers
move off their respective contacts, and the circuit closers 27 closes the circuit
between the contacts 22 and 23, and under these conditions the current through the
field magnet enters at the post 5, passes through the portion of the coils to the
post 20, thence to the contact plate 22, by the circuit closer 27 to contact plate 23,
thence to the post 21, and through the remaining coils of the field magnets to the
post 6, and to line, putting the coils of the field magnet in series, so that the motor
will run properly under its load.
As shewn in the drawing, the switch arm S is in its normal position with the
circuits broken, so that no current passes through he switch and to the motor, but
when the hand rope H is operated, the shipper bar F is moved through the medium
of the segmental lever G to operate the segmental lever E, and thence the switch

page_text: arm. The segmental lever E is shewn as connected to the shipper bar through the
medium of springs between the free end of the lever and lugs or supports on the
shipper bar against which the springs bear. These springs are preferably of such a
strength and resiliency, that under ordinary conditions, the segmental lever will be
moved in accordance with the movements of the shipper bar, but if any obstructions
or hindrance to the movement of the segmental lever occurs, they will be compressed
to a greater or less extent before the lever is operated.
To secure the switch arm in its normal position with a dead brake of the circuit,
there is provided some suitable locking device, and while this may be variously
constructed, it is here shewn as a simple pawl e¹ which is normally under the stress
of a spring e², and this pawl engages a notch in the stationary bar F1 secured to the
framework of the device, and this holds the brush in position until the locking
device is released. Various ways of releasing the device may be adopted; as
illustrated the shipper bar F is provided with a recess f¹ having inclined sides
which engage the extension es of the pawl e¹, and lift it out of the notch in the
bar F'.
The parts being in the position shewn in Fig. 1, and the operator pulling the
hand rope H to start the engine, will move the shipper F, and as the segmental
lever E is locked, the spring e will be compressed, and require more than ordinary
force or pull to be exerted upon the hand rope to move the shipper bar. As soon"
as the bar has moved sufficiently to cause the incline of the notch in the bar to
raise the pawl e¹, and unlock the segmental lever, the lever will be operated freely
to control the circuit, and the springs will maintain the lever in its normal relation
to the shipper bar throughout its movement, and it will move freely, in harmony
with the movements of the bar. When however, the elevator is stopped and the
switch is moved into its normal position (or in any other desired position if the lock
is correspondingly arranged) the lever will become locked, and require the extra
force to move it from its locked position, and the operator in the car will readily
understand from the feel of the rope, or the extra force required to leave it, that
the switch arm.
is in the proper position, and can move the elevator with the
assurance that everything is correctly arranged, and in position to leave with safety.
The same general construction and arrangement of parts may be carried out by
electrical means instead of mechanical, as shewn in Fig. 3, wherein the shipper
bar F supports the coils of a solenoid m on either side of the segmental lever E.
Mounted on this lever is a core n extending on through either side into the coils of
the solenoids. The coils of the solenoids may be connected in the main circuit of
the motor, or in a separate local circuit, the latter being indicated for convenience,
and the terminals are connected by a flexible conductor or brush y bearing on an
extended contact m', so that the coils of the solenoid are in circuit whatever may
be the position of the shipper bar.
The shipper bar is preferably provided with studs & on either side of the segmental
lever, which while allowing a certain freedom of movement, or backlash so to speak,
between the shipper bar and the lever, will insure the lever being moved when the
shipper bar has moved a certain extent.
The pawl e' attached to the segmental lever is in this instance made of magnetic
material, or has a portion of it so made, and takes into the notch in the stationary
bar F. Above the pawl is arranged a magnet q the coils of which are in a branch
of the electric circuit, one end being connected to the contact which normally rests
on an insulated portion of the shipper bar, but which is adapted to make contact
with the contacts s at either side of the insulated portion.
From this arrangement it will be seen that the parts are normally locked, and
the operator moving the shipper bar, the core of the solenoids will pass into the
coils thereof against the tendency of these coils to maintain the core in equilibrium
between them, but as soon as the contact t bears upon either of the contacts 8, the
branch circuit is completed, and a portion of the current flowing through the
magnet energizes the same, and this raises the pawl e' out of the notch in
the stationary bar F, and the attraction of the core of the solenoids causes the

page_text: It
segmental lever to assume its normal position between the coils of the solenoid, and
the switch is then moved in accordance with the movements of the shipper bar.
will be understood that the operator on the car has not only to move the shipper
bar, but to overcome the tendency of the core of the solenoid to maintain its normal
position, and this will require an extra force which the operator will understand
from the feel of the rope to indicate that the segmental lever with its connecting
switch controlling the motor is in its normal position.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed (as communicated to us
by our foreign correspondents), we declare that what we claim is :-
1. The combination with an electric motor, of a switch controlling the circuits of
the motor, and means for automatically altering the resistance of the field magnet
coils after the motor has started, substantially as described.
2. The combination with the motor, of a switch controlling the circuits of the
motor, and means for automatically interposing a resistance in the field magnet
circuit of the motor, after the motor has started, substantially as described.
3. In an electric elevator, the combination with the elevator, and the electric
motor connected to operate the elevator of a switch controlling the circuits through
the field and armature of said motor, and means for automatically varying the
resistance of the armature circuit, and means for automatically varying the resistance
of the field magnet circuit, substantially as described.
4. In an electric elevator, the combination with the elevator, and the electric
motor connected to operate the elevator, of a switch controlling the circuits through
the field and the armature of said motor, a resistance device normally in the
armature circuit, and means for automatically cutting out said resistance, and means
for automatically cutting in the field magnet circuit a resistance device when the
motor has started, substantially as described.
5. In an electric elevator, the combination with the elevator, and the electric
motor connected to operate the elevator, of a switch controlling the circuits through
the field and armature of said motor, a resistance device normally in the armature
circuit, and means for automatically cutting it out, and means for including more or
less of the field magnet coils in the field magnet circuit of the motor, substantially
as described.
6. The combination with the electric motor, and a switch controlling the circuit
through the field and armature thereof, a cam connected to the switch, a
resistance normally in the armature circuit, a solenoid also in the armature circuit,
and a lever controlled by the can connected to operate the core of the solenoid, a
contact arm carried by the solenoid, and arranged to vary the resistance of the
circuit through the field magnet coils of the motor, substantially as described.
7. In an electric elevator, the combination with an electric motor, of a switch
controlling the motor, and the hand rope for controlling the switch, of a locking
device for the switch, and means connected to the hand rope for releasing the
locking device, substantially as described.
8. In an electric elevator the combination with the electric motor, the switch
controlling the motor and a hand rope for operating the switch, of a locking device
for temporarily holding the switch against the movement of the hand rope, a spring
connection between the switch and the hand rope and devices for releasing the lock
of the switch when the hand rope has moved a sufficient distance, substantially as
described.
9. In an electric elevator the combination of the electric motor, a lever con-
trolling the switch, a locking device on said lever, a hand rope for operating the
switch, a shipping bar connected to the hand rope, spring connections between the
shipping bar and lever, and means connected with the shipping bar for releasing
the locking device of the lever, substantially as described.
10. In an electric elevator, the combination of the electric motor, the switch, the
lever, the spring actuated pawl connected to the lever, and forming a locking device

page_text: therefor, the shipper bar, springs interposed between the shipper bar and lever, and
a notch having inclined sides on the shipping, ban to release the locking pawl, sub-
stantially as described.
11. The combination with the electric motor of an electrio elevator, the switch
controlling the motor, and a locking device therefor, of a shipper bar and connections
between the shipper bar whereby the bar may be moved without moving the switch,
and releasing devices operated by the shipper bar for releasing the locking devices,
substantially as described.
12. In an electric elevator, the combination of the switch, springs for moving the
switch, means connected with the cage for compressing the springs without moving
the switch, a locking device for temporarily holding the switch against the pressure
of the springs and means for releasing the locking device when..the, springs are
compressed, substantially as described.
Dated this 20th day of May 1892.
PHILIPM. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicants.