Improvements connected with Brakes for Electric Railway Vehicles and the like.
Year: 1899

page_text: Date of Application, 22nd Dec., 1899--Accepted, 14th Apr., 1900
COMPLETE SPECIFICATION.
Improvements connected with Brakes for Electric Railway Vehicles
and the like.
We, THE BRITISH THOMSON-HOUSTON COMPANY, LIMITED, of 83, Cannon
Street, in the City of London, Electrical Engineers do hereby declare the nature
of our said invention (which has been communicated to us from abroad by
Frank E. Case, residing at Schenectady, in the County of Schenectady, State
of New York, United States of America, Electrical Engineer,) and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement: —
Our present invention has for its object to provide a system of train or motor-
car braking, particularly useful in connection with electrically propelled
apparatus.
the
Our invention contemplates the use of a mechanical brake applied
action of an electric or other motor. One novel feature resides in the idea of
arranging the gearing between the motor and brake in such a way that the
friction of the gearing will be sufficient to hold the brake in whatever position
it may at any time be left by the stoppage of the motor. We may accomplish
the same result by artificially increasing the friction of the device whenever
the motor is stopped, as by the operation of a friction brake.
It will be obvious that each motor may apply one or more brakes as desired,
and that the motors and brakes may be placed upon the car or train whenever
necessary.
Another feature of this invention consists in regulating the braking motor
by contacts on the main motor controller, these contacts being so arranged that
at the proper point in the movement of the controller the brake motor will be
energized to apply the brake shoes, and at another controller position the brake-
shoes will be released, preferably by reversal of the motor.
The latter operation is usually effected at or about the time of starting the
car or train; the contacts may therefore, be so placed as to connect the motor
at the first power point of the controller, or they may be arranged to release
the brakes before the current is admitted to the propelling motors; it will
generally be convenient to utilize the trolley current for this purpose. In the
application of the brake, the motor may, if desired, be operated by current
from the propelling motors acting as momentum-driven generators, or the
trolley-current may be used in this case also. Under some conditions a storage
battery may be utilized to advantage.
It is within the scope of this invention, as stated above, to so select the gear-
ing between the motor and brake-rigging, that the former must be positively
operated to either apply or release the brakes. With this arrangement after
the brakes are once set, the current may be turned off from the operating motor,
and they will remain set as long as desired, without waste of energy. Thus,

page_text: our invention will also provide for a train or a single motor car driven by
electric motors and equipped with electric brakes, means for stopping the car
and for holding it on grades after the speed has become so low that the gene-
ration of current has practically ceased; or after the car has come to rest, when
from the consequent cessation of current the electric brake-shoes no longer have
sufficient adherence. For our purposes we use a small motor, to which is con-
nected a winding drum taking up the chain of the ordinary brake-rigging and
applying the shoes. The motor acts preferably through a worm gear, so that
after it has once wound up the drum, current may be turned off while the car
stands, and the motor would then be reversed in order to unwind the chain and
release the car.
While we have used the trolley current in the way pointed out, it is manifest
that any convenient source of current might be employed; for instance, as
already stated, we might employ a storage battery which would be charged
from the trolley line during the running of the train. This could be done by
putting the battery in shunt to a part of the motor regulating resistance, or in
any other convenient way. With the battery thus energized, the motor may be
operated from it to apply and release the brakes, or for either one of these pur-
poses, without departing from the invention. Ordinarily the simplest and most
apparent application of the invention will be to use the trolley current.
The accompanying drawings show an embodiment of the invention: Fig. 1
is a plan view of the trucks of two motor cars, equipped with our invention
and is to be taken as typical of any number of cars which may be convenient.
Figs. 2 and 3 are end and side elevations respectively of a suitable motor and
winding drum. Fig. 4 is a diagrammatic development of a suitable controller
showing contacts which illustrate this invention. Fig. 5 is a diagram of a
modification in which a storage battery is used. Figs. 6 and 7 show a train
equipped with the invention.
In Fig. 1, A, B are the two trucks equipped with the motors C, C. Each of
them is provided with the usual brake-rigging I), connected by chains F with
the winding drums of the respective motors E, E¹. The usual brake-shoes, of
electric type, are provided, as indicated at H, H. The ordinary brake-shoes
applied to the tread of the wheel, are shown at h on both the cars. The con-
trolling device is indicated at K.
Fig. 2 shows an end elevation of one of the brake-motors. One of the gears,
or, as it is commonly called, the "pinion" of the motor e drives another gear e¹.
Upon the shaft of the latter is a worm e² connecting with the worm-gear f of
the winding drum. The rotation of the drum acts to draw up the chain F of
the brake-rigging, the levers of which are shown in plan in Fig. 1, and work
in the ordinary way, well understood in the art, not requiring description.
The operation of so much of the device will be readily apparent.
In Fig. 4 a proper controlling device is shown developed in plan. The fixed
contacts are indicated by the circles, and the moving contacts by the rectangles.
The connections for regulating the propelling motors will not be particularly
described, as they form no part of this invention, and in general are well known
in the art. It may be said, however, that the contacts upon the left form
braking portion of the switch, and those upon the right are designed to regu-
late the propelling motors C, C from rest to full speed by the ordinary series-
parallel methods: but our invention may be well applied with other forms of
motor regulating switch. The brake motors are illustrated diagrammatically
at E, E. In the operation of the controller, when the contacts upon the left
are turned, the usual electric brake circuits would be completed until the con-
tact 1, by which the trolley current enters the controller, reaches the contact 1b
on the left. At this time all of the contacts 1 to 4 are upon the two con-
tacts 1b, 3b. Current therefore passes from the trolley T to contact 2, through
the armatures A¹ and A3 of the brake-motors in multiple, back to contact 3, to
contact, and through the fields F¹, F in multiple, to ground at G. The motor

page_text: armatures are thus rotated, and the brake shoes would be applied. When
this has been done, the controller may be turned to the off position until it is
desired to start the car. At the first position of the motor regulating contacts
shown on the right of the switch K, the trolley would touch contact 1°, and
then current would pass to the contact 3ª, passing through the armatures A¹, A³
in multiple, but in the reverse direction, and then returning to contact 2* pass
to 4, and through the fields F1, F2 to ground, thus reversing the motors. Of
course, as soon as the brakes are released, the controller may be further rotated
to propel the car, thus breaking contact with the plates 2 to 4ª, and cutting
out the motors E, E¹ at or before the time when the motors C, C are brought
into circuit. The motors E, E¹ may be very small and designed for high current
capacity for a short time; in fact, they may be of such size that if kept in
circuit for any great length of time, they would be destroyed, and yet be used
for our invention without risk, as they may be of high counter electromotive
force and run very fast, winding up the chain with great rapidity; the static
friction of a car at rest being great, the brake shoes h need only be slightly
applied to hold the car even on a considerable grade.
Where other forms of gearing than the worm are to be used, a modified form
of motor may be desirable; the invention however does not reside so much in
these engineering details, as in the general idea of a controlling device with
contacts arranged to operate a motor for winding up a brake chain when
applied in one direction, and for releasing it when applied in the other. It is
manifest that if the brake and power cylinders of the controller are in different
switches, as is sometimes the case, the contacts for applying the motors in one
direction may be, if desired in one switch, and for reversing them may be in
the other. Of course suitable resistances may be used in any desired relation.
We have not thought it necessary to illustrate these details.
In Fig. 5 we have shown a modification in which a storage battery may be
employed, the connections of which will be apparent from an inspection of the
figure. Only one of the motors E is shown, but the application to another or
other motors will be readily apparent. In connection with this figure we have
also shown that instead of using a worm gear, other forms of gearing might
be used: the band-brake M may be applied to the motor, being actuated by a
lever O, pivoted at o, the band brake being applied by a spring 01. When.
however the motor armature A¹ is to be actuated the current would pass around
the coils of the electro magnet N, releasing the lever 0, and slacking the band,
so that the motor might rotate so long as the current was on.
As soon, how-
ever as current ceases, the brake is applied and the motor quickly stops. In
some cases this may be perferred to the worm, as it avoids the inherent friction
of the latter device, and does not waste current in the magnet N, the coils of which
are only in circuit while the motor is running.
In Figs. 6 and 7 we show the application of the invention to a train system
composed of a number of independent units, that is, of cars each of which is
provided with its own propelling motors, and a controller regulating these
motors, with master controllers located at different points along the train and
each controlling the operation of all of the motor controllers. We make no
claim in this application, except in so far as the application of the present
invention is concerned, to such a system.
In these figures A. B, B' are the motor cars or units of the system K, K₁, etc.,
are the motor controllers, Q1, Q2, etc. are the master controllers situated at con-
venient points. The arrangement is best understood from Fig. 7, the same
reference letters being employed. Each of the master controllers Q1 acts to con-
trol the rotation of pilot motors, so called P, P1, the latter operating the con-
trollers K, K' simultaneously in the same direction. The different trolleys TT
which are here illustrated as suitable for a third rail system, are connected in
multiple to the train wire TW. All of the pilot motors are also connected in
multiple to the set of wires illustrated. When for instance, the controller Q¹

page_text: is rotated; its two upper contacts are connected by the moving contact on the
left, and its two lower ones similarly connected. The circuit would therefore
be from the trolleys, to the upper contact of the trolley Q1, to the next contact
in order, then through the armatures of the motors P, P₁ in multiple, then
back to the third contact, of the controller, then to the fourth contact, then
through the fields of the motors in multiple to ground. The controlling
devices K, K¹ would be rotated so long as the motors revolved, and when the
train has come to full speed, the controller Q₁ could be turned off.
When it is desired to stop the train, the controller Q¹ may be oppositely
rotated. By tracing the connections it will be found that the relation of arma-
ture and fields in the pilot motors is reversed so that they run backward and
rotate the controlling device either to the off position as illustrated in Fig. 4, or
passing still further, to the position in which the brakes are applied, and finally
to its position in which the ordinary brake-shoes are applied by the motors E..
It is manifest that with such a system the entire braking may be done by
the motors E if desired. Of course the operation of any of the other master
controllers, they being all connected in multiple, would be identical with that
of the one described.
Having now particularly described and ascertained the nature of our said
invention (as communicated to us from abroad) and in what manner the same
is to be performed, we declare that what we claim is:
-
1-A brake system for an electrically-propelled car or train, comprising a
propelling motor or motors, a brake, a motor for applying the brake, and a con-
trolling device having contacts for regulating the propelling motor or motors,
contacts at one of its positions for actuating the brake-motor in one direction
and contacts at another point for reversing them.
"
2-A brake system for an electrically-propelled car or train, comprising a
brake-motor or motors for some or all of the cars, propelling motors, and a con-
trolling device governing all of the motors on any car from a single piece of
apparatus.
3
3-An electric brake system for a car or train, comprising a rotary motor
for each car, a drum actuated by cach motor and applying or releasing the
brake-rigging in accordance with the direction of rotation of the motors, and a
controlling device regulating all of the motors, the controlling device having
contacts at one of its positions for driving the motors in one direction, and
contacts at or about the first power point for reversing them.
4 An electric brake system for a car or train, comprising a rotary motor
on each car, a drum actuated by each motor applying or releasing the brake-
rigging in accordance with the direction of rotation of the motors, a braking
device for each of the motors, released or applied by turning on or off, of current,
and a controlling device regulating all the motors.
T
5 A controlling device for an electrically-propelled car or train, equipped
with propelling motors and separate braking motors, having contacts for regulat-
ing the propelling motors, braking contacts utilizing the propelling motors as
generators, and a contact or contacts on the brake side for driving the brake
motors in one direction to apply the brakes, and other contacts for driving them
in the opposite direction to release the brakes.
6-The combination of a number of motor cars united in a train, each car
having propelling motors, rotary braking motors, and a controller for all the
motors of the car, and being a complete unit capable of individual operation,
with master controllers at different points in the train, and means regulated by
the master controllers for simultaneously operating all the motor controllers.
7-The combination with a motor-car, of a mechanical brake therefor, a
motor for applying said brake, a mechanical connection between the motor and
the brake, and a control device for said motor; the arrangement being such
that the motor will, upon the proper application of current, apply or release the

page_text: brake and that the brake will, upon the interruption of the motor circuit.
remain in the position in which it may then happen to be.
Dated this 12th day of December 1899.
THE BRITISH THOMSON-HOUSTON CO. LTD.
ALFRED CLEMENTS,
Assistant Secretary.
J. J. MANHEIM,
Directors.
T. R. THOMPSON, ;