Improvements in Electric Brakes for Railway Trains.
Year: 1889

page_text: 1 COMPLETE SPECIFICATION.
. Improvements in Electric Brakes for Railway Trains.
We, WATSON PLAYTOR WIDDIFIELD, Lumber Merchant, residing at Uxbridge, in
the County of Ontario, in the dominion of Canada, and Subject of the Queen of
Great Britain, and ALEXANDER HAMILTON BOWMAN, Electrical Engineer, residing at
Packerton, in the County of Carbon, and State of Pennsylvania, United States of
America, and citizen of the United States, 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 :---
Our invention relates to an electric brake system, in which the rotary momentum of
the car axle is automatically communicated to the brake lever, through the medium of
simple mechanism and in electric circuit.
The object of the invention is to provide means whereby the efficiency of the electric
current may be increased. Instead of applying the electricity to lift a large friction
pulley against the car axle, it is caused to place a smaller friction pulley against the
axle, while the force communicated to the latter, pulley is transmitted by suitable
mechanism to the large pulley. This said force throws the large pulley against the
car axle, and being rotated causes the brakes to press against the car wheels. A
prominent feature of the system consists in the simplicity of the mechanism employed
to carry out the invention.
Referring to the drawings, figure 1 sheet 1 is an ortho-graphic side elevation
partially in section of a portion of a car truck and brake therefor. In the same
figure are shown, in diagram, the electric circuits and connections.
Figure 2 Sheet II is a three sided view of a larger portion of a car truck and brake
therefor. The side not shown in figure 2. is represented in figure 1.
Figure 3 sheet I is a three sided view of one half of the electric coupling, of which
the other half is an exact duplicate.
In the above named figures, such portions are broken away or omitted as may tend
to cause confusion.
The system consists of the combination of a car axle a, supporting the two car
wheels an enlarged portion c, or collar upon the axle; two friction wheels or

page_text: pulleys d, and e, the former being a little more than twice as large as the latter (the
proportion need not be accurate); an axle or shaft f, for the. pulley d; and another
shaft 9, for the pulley e; a bent lever supporting the smaller pulley, and pivoted to
a suitable support i by means of a pivot an armature connected to the lever h, by
means of a non-magnetic, rod -the armature being represented as a core k of a
magnet or solenoid F.; a rack 1, of non-magnetic metal, secured to the upper part of
the core, and gearing into a pawl or ratchet m, whose opposite end is over the core of
another magnet or solenoid p & which is pivoted to the magnet F, (when the core
of solenoid P is attracted upwards, the core k, is liberated and falls downwards by the
action of the spring arm of the lever hand by gravitation); a second bent lever »,
supporting the axle f, and pivoted upon a journal o upon the support of a chain »
connected at one end to the second bent lever, through medium a third w
and at the other end, to the axle of the smaller pulley e; and a chain connection s
between the shaft of the large pulley and the brake lever t. The lever wis pivoted on
support between the chain end and that end which connects with the lever . The
chain is preferably in a vertical line.
The shaft, fits rather loosely in the bearing w, (fig. 2) so that the pulley may
move and strike against the collar c, when the lever, is operated by the
chain v.
The shaft 9: also and for similar reasons, is loose in its bearings a.
The lever is a spring lever, being formed of elastic plate metal, such as the best
sheet, for example. The arm of the lever by which the pulley e is supported is in a
plane at right angles to that arm of same lever attached to the core j. The latter arm
is flat in a horizontal plane, so that it forms an elastic connection between the said
core and the pulley e.
The lever is of such a length that when the brake is on full, the chain-end strikes
the bearing or support of the outer end of the shaft g, opposite to the end on which
the pulleye is fixed: This bearing, and the supports or arms, and i, are represented
as projecting from a containing box I; for the said magnets, a cylindrical cover for
the box being shown in figure 2. The pivot on the arm or support q, for the lever w
is slightly nearer the box than the upper end of the lever r, so that the chain end of w
may be substantially in a vertical line passing through the axis of the shaft g.
The cores of the magnets or solenoids are only about half the length of the solenoids,
and the non-magnetic rods n and are of much smaller diameter than the cores, while
the holes in the iron spools of the solenoids at the upper portions are correspondingly
smaller than in the lower portions, as represented. At the lower ends of the cores,
iron discs are attached thereto, and form integral portions of the cores. By the above
construction of core and solenoid a long pull may be obtained, so that the stronger
the current in the solenoid F, for instance, the greater will be the pressure of the
pulley upon the collar c. This collar c is made of alternate rings of metal and fibre
mounted upon the shaft or axle a, and formed thereon by surrounding the shaft with a
suitable mould and casting metal and inserting the fibre alternafely.
It is evident that the magnets and cores may be multiplied in order to increase or
distribute the power, or for any other reason.
The electrical portion of the system consists of the combination of two generators,
the one A being located in or on the locomotive of the train of cars to which our
invention is applicable, and the other A being located upon the last car of the train;
one or more couplings (one being shown in external elevation) serving to connect the
conductors which pass from the generators, of which there are two more M. and M³
similarly located; a conductor B connecting similar poles of the generators A and A':
two other conductors C and D, D being open in the last car at switch X, connecting
the remaining similar or like poles of the same generators; the magnet F being in the
circuit of the conductors B and C, and the magnet p being in the circuit of the
conductors B & D a switch E normally open and in conductor D; a switch P
normally open and in conductor C, both of said switches, in practice, being located
upon the locomotive and rear car; and a switch P¹, normally open and in conductor C
and located on the last car of the train the switches P and P1 being of

page_text: magnetic material such as soft iron. Magnets Qand Qare respectively beneath
switches P and P', and, being normally in closed circuit with batteries M and M' by
conductor T (one of the generators M and M may be omitted if desired, or one or
more cells of battery A or A¹ may be employed) they maintain the said switches in an
open condition, against the tension of the springs R and R. When the wires or
conductors break at one or more points between the locomotive and the last car, as for
instance, at the couplings L, by accident or inadvertance, tho switches P and P will
close an active current through what may be termed the brake magnet F and thereby
bring all the cars to a gradual but quick stop, as will appear hereafter from the statement
of operation of the system.
Upon the box-I-in any convenient portion-is located a coupling L¹ similar to
that indicated by L, except that the springs S, which are the terminals of the
conductor T, are omitted, because the conductor T does not pass through the
coupling L. The coupling, seen in half, in fig. 3, consists of the combination of a
metal frame U, hollow and containing three terminals V VI V" respectively belonging
to the conductors BC and D and mounted upon insulation W in the interior of the
frame or casing U, and provided with a terminal S, secured to the outside of said
casing. Each terminal is springy or clastic and is adapted to press upon its mate in
the other half, so that the outward appearance becomes substantially as shown at L in
figure 1. This portion of the system may be manipulated by pushing and pulling the
two halves with one's hands in order respectively to couple and uncouple the
circuits. The wire T, in the system becomes continuous by its attachment to
the terminal S.
The modus operandi, succinctly described, is as follows:
Assuming that the brake is in its normal condition, as exhibited in the illustrations,
and that the train is in motion, and that it is desired to stop or slacken the said train,
the engineer, by means of a convenient handle, not shown, closes the switch P, so
that, from the nature of the construction, hereinbefore described, the solenoid F
becomes energized and attracts its core upwards. If convenient rheostats Z and Z
(one in locomotive and one in rear car) are introduced in this circuit conveniently
near the switch P, or if other means are provided for varying the current, it is
evident that the current may be gradually applied. The spring lever becomes
operated through the medium of the rod j, in such a manner that the small friction
pulley e is pressed against the collar c with a force or pressure dependent upon the
amount of electric current applied to the solenoid F. The elastic or spring arm of the
lever h serves to regulate the application of the force.
If this arm were not slender enough to be springy, or if an equivalent clastic
connection were not provided, the brake would not be smoothly applied.
When the said pulley e touches the rotating collar c, it turns and its shaft g winds
up the chain », which is attached to the said shaft and also to the lever w. If the full
current is applied it is interesting to note that the chain end of said lever w will
descend until it comes in contact with the arm which assists in supporting the shaft y,
and which is shown in figure 2.
The consequent operation of the lever w, turning about the fulcrum on the arm g,
rotates the lever r until the large pulley d is pressed against the collar c. A rotation
of this pulley now occurs and its shaft winds up the chain s, thereby operating. the
brake lever which is connected by any suitable mechanism to the pressure blocks of
the brake.
The functions of the rack I and ratchet m, are to retain the pulley e against the
collar c.
This pulley e may be removed from the collar c and brought again into its
normal position by closing the switch E, thereby energizing the magnet p; whose
core n rises and liberates the ratchet m, so that the core falls. A suitable stop, not
shown in figure 1, may be provided for the cores & and n. In figure 2, the bottom of
the box I, is shown as such a convenient means, the solenoids F and p being placed in
this figure, nearer the bottom of said box.
If the coupling L accidentally or otherwise breaks apart, or if the electric conductors
break, the train will automatically stop, because the current will be cut off from the

page_text: magnets and Q, whereby the switches P and P will be closed, and whereby
therefore, a similar operation will occur as mentioned above. As the magnets Q and Q¹
are preferably on the first and last vehicle of the train, all the brakes on all the cars
will be applied by the breaking of the train into two or more sections.
If for any reason any one of the brake mechanisms is to be cut-out of circuit the
coupling L₁ may be separated by hand.
It is evident that the solenoids for applying and releasing the brake may be termed
electric motors.
The apparatus in the locomotive is preferably duplicated in the rear car, so that the
wliole system can be operated from either end of the train.
The generator A serves for all ordinary purposes, while the generator A¹ serves in
case of accident, or occasional use; hence the generator A¹; the generator M¹, and
conductor T are auxiliary.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
1. In a system of railway brakes, the combination of a brake adapted to be applied
to car wheels of a railway train and an electric motor or similar electric device
adapted to release said brake.
j
2. In a system of brakes for a railway train, the combination of an electric motor
or similar electric device, adapted to apply the brake; and a second electric motor
adapted to release the brake.
3. In a system of electric brakes for a railway train, the combination of an electric
motor adapted to apply the brake; a second electric motor adapted to release the
brake two independent electric circuits respectively including said motors; a
tbird electric circuit provided with an electro-magnetic closing switch for the first
motor's circuit; and a suitable closing switch for the second motor's circuit: and
electric generators in circuit with said motors and with said electro-magnetic closing
switch.
4. In a system of electric brakes, the combination of two friction pulleys, the one
connected to the brake lever, and the other to the armature of an electric solenoid or
similar magnet; and both being connected to each other and applied to a collar upon
the car axle, the said collar consisting of alternate collars or rings of metal and fibre
mounted upon the car axle.
5. The combination with the friction pulleys of a car brake, of a collar upon which
said pulleys presses, the said collar consisting of alternate metallic rings and fibre
rings mounted upon the car axle.
6. In a system of electric brakes, the combination of a friction pulley of a certain.
size, supported adjustably relatively to the car axles; a mechanical connection between
the axle of the pulley and the brake lever; and a smaller pulley of less diameter also
supported adjustably relatively to the said car-axle, and connected through a chain
with the operating lever of the large pulley; the said smaller pulley being connected
to the armature of an electro-magnet, which is included in a suitable electric
circuit.
7. In a system of electric brakes, the combination of two friction pulleys, the one
connected to the brake lever, and the other to the armature of an electro-magnet;
and both being geared to each other and to the car axle.
8. In a system of electric brakes, the combination of a car axle provided with a
collar; a friction pulley supported upon a lever, which is connected to the shaft of a
pulley of smaller diameter; both pulleys being adjustable relatively to the said
collar; a lever connected at one end to the smaller pulley, and at the other end
elastically to the armature of an electro-magnet; a retaining device or clamp for the
armature; said device consisting substantially of a rack and ratchet; and a second
electro-magnet whose armature is in the path of the said ratchet, and adapted to
release the same from said rack, the said magnets being included in suitable electric
circuits.

page_text: 9. In a system of electric brakes, the combination of an electric brake provided
with a magneto-electric releasing device; the electric brake and the releasing device
being in independently electric circuit, and a single switch being provided for both
circuits.
10. In a system of electric brakes, the combination with the armature of an electric
magnet, of an elastic connection between the said armature and the lever of the
friction pulley of the brake.
11. In a system of electric brakes, the combination with an auxiliary friction pulley,
of an elastic connection between the lever of the pulley and the armature of the
operating electro-magnet.
12. In a system of electric brakes for railway vehicles, the combination of a pulley
in frictional contact with one of the axles of the wheels of the vehicles; a shaft
carrying said pulley and supported at one end to a suitable hearing, and at the other
end by one arm of a pivoted bent lever; a second pivoted lever hinged at one end to
the remaining arm of the first lever, and at the other end to a chain; a second pulley
in frictional contact with the said axle and whose shaft is supported by a suitable
bearing at one end and upon one arm of a bent third pivoted lever at another point,
the said shaft being connected to said chain; a second chain connecting the shaft of
the first pulley to the brake lever; an electro-solenoid whose core is connected
elastically to the arm of the lever which supports the second pulley; a ratchet or
toothed projection for the said core and a ratchet gearing into said rock; and a second
solenoid whose core is adapted to trip or ungear said ratchet; the said solenoids, or
similar magnets being included in independent electric circuits, substantially as
hereinbefore described and illustrated by the drawings.
13. In an electric brake system, the combination of two electric generators, the
one A being located in the locomotive of the train of cars to which the system is
applicable, and the other A¹ being located upon the last car of the train; one or more
electrical couplings connecting the conductors which pass from the generators, of
which there is one more generator M similarly located; a conductor B connecting
similar poles of the first named generators; two other conductors connecting the
remaining similar or like poles of the same generators; a magnet F in circuit with
the last named conductors B and C, and a second magnet being in circuit with the
conductors, B & D.; a switch E normally open and in conductor D; a switch P,
normally open and in conductor C; both of said switches being located upon the
locomotive and on the rear car; a switch P¹ normally open and in conductor C and
located on the last car of the train; the switches P and P¹ being of magnetic material
such as soft iron; and magnets Q and Q₁ located within attrracting distance beneath
the said switches P and P. and normally in closed circuit with battery M, by a
conductor T, and thereby maintaining said switches open against tension springs R
and R respectively connected to said switches; substantially as hereinbefore described
and illustrated by the drawings.
14. In combination with a system of electric brakes an electric coupling con-
sisting of the combination of a metal frame, hollow and containing three electric
terminals VV V respectively belonging to the conductors B, C, and D and
mounted upon insulation in the interior of the said frame; and a terminal S mounted
upon the exterior of the casing; substantially as hereinbefore described and illus-
trated by the drawings.
11 Ind day of January 1889