Improvements in Electric Railways.
Year: 1895

page_text: Date of Application, 20th Aug., 1895-Accepted, 2nd Nov., 1895
:
Improvements in Electric Railways.
A communication by JAMES FRANCIS MCLAUGHLIN, of 1742 Diamond Street,
Philadelphia, in the State of Pennsylvania, United States of America,
Electrician.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6, Bank Street, Manchester,
both in the County of Lancaster, 118 New Street, Birmingham in the County of
Warwick and 31 High Holborn in the County of Middlesex, Civil Engineer, do
hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement :-
:
This invention has reference to improvements in electric railways in which
underground switches, for coupling a supply conductor to feeding conductors or
contacts, are operated by travelling electro-magnets carried upon the motor cars.
One of the objects of this invention is to provide an underground switch, which
will be positively locked when in the open position and which will be unlocked and
closed only when covered by a motor car.
Another object of this invention is to provide improved means for collecting the
current from the exposed contacts, and also to guard against a failure of the
system, if, as sometimes happens, the normal energizing coils of the travelling
electro-magnets should burn out, or their circuit otherwise broken. This is accom-
plished by providing the magnets in addition to their normal windings, with auxiliary
windings, which are automatically included into the external circuit, when the
normal windings become ineffective.
All this will more clearly appear from the following detailed description taken in
connection with the accompanying drawing, in which :
Figure 1, is a cross-section of a switch box constructed in accordance with the
present invention, with the travelling, switch-operating magnets shown in
elevation.
Figure 2, is a section of the switch box at right angles to that shown in
Fig. 1;
Figure 3, is a perspective view of the switch lever.;
Figure 4, is a cross-section of a switch box, constructed in accordance with the
present invention, and more particularly adapted to a road in which exposed
sectional feeding conductors are used;
Figure 5, is a section partly in elevation at right angles to that shown in
Figure 4;
Figures 6 and 7, are diagrams illustrating the circuit connections of an electric
railway system using switch boxes constructed in accordance with the present
invention;
Figure 8, is a side elevation of the improved collector together with two switch
boxes in operative relation thereto, and a conventional representation of the car
motor, switch operating magnets and their controlling devices;
Figure 9, is a plan view of two switch boxes, with two travelling switch operating
magnets and a current collector, and
Figures 10 and 11 are end and side elevations, respectively, of the automatic
controller for the circuit of the auxiliary coils of the travelling magnets.
Referring to the drawings, and more particularly to Figures 1, 2 and 3, there is

page_text: shown a rectangular switch box 1, the side walls of which flare slightly from the
bottom upwards and terminate in a ledge 2, on which rests, and to which is secured,
by screws or otherwise, the cover 3. Exterior to the ledge there is formed a
channel 4, the outer wall of which is a continuation of the sides of the box and rises
to the level of the top surface of the cover, thereby forming a receptacle for water-
proof cement 5, which serves to seal the joint between the cover and the box.
Secured to the bottom of the box and within the latter, is a base plate 6, from
opposite sides of which rise standards 7, receiving at their upper ends a pivot bolt
or rod 8, on which the switch lever is mounted. This switch lever, which is best
shown in Fig. 3, is composed of two iron bars 9, 10, joined near their ends by cross
pieces 11, centrally perforated for the passage of the pivot bolt 8. The bar 9,
carries near each end an insulating block 12, fast on its under face and projecting
laterally therefrom. Each insulating block has near its outer end a U-shaped
metal strip or jack 13, adapted to enter between and bridge the projecting ends of
two metal brushes 14, 15, and 14', 15'. respectively. The brushes 14, and 14', are
secured to insulating blocks 16, 16', fast on the under face of the cover 3, and
these two brushes are connected in multiple arc by a conductor 17, to a branch
conductor 18, entering through a neck 19, formed in one side of the switch box,
the said branch conductor coming from a supply conductor 20, (see Fig. 6) fed by
a generator 21, located at the central station. The other two brushes 15, 15' are
fast on the lower ends of two iron contact blocks 22, and these blocks are mounted
on, but insulated from the cover 3, each block having its lower end projecting into
the interior of the box close to the bar 9. The insulating material 23, interposed
between these blocks and the box cover is indicated by appropriate shading. It
will be seen that the switch lever operates two switches in multiple, thus preventing
or greatly reducing the sparking when the circuit is ruptured.
There are two other iron blocks 24, 24, on the box cover, and these blocks also
project through the cover with their lower ends close to the bar 10. The two
blocks 22, are in line with each other and in the vertical plane of the line of travel
of an electro magnet 25, preferably of the horse-shoe type, and having its pole
pieces provided with iron wire brushes 26, which, as the magnet passes over the
switch box, make contact with the exposed faces of the contact blocks 22, by which
these contact blocks constitute, temporarily, extended pole pieces of the magnet,
thus causing the attractive force of the magnet to be exerted under the most
favorable conditions, that is, the pole pieces of the magnets are brought into close
relation to the bar 9, which thus becomes an armature for this magnet. The action
of the magnet 25, which is placed at or near the front of the motor car or car
truck, is to draw the armature 9, towards the contact blocks 22, until the jacks 13,
have closed the circuit between the brushes 14, 15, and 14', and 15. The switch
lever is held in the closed position by the friction between the spring brushes and
the jacks.
The two iron blocks 24, are also in line with each other and in the vertical plane
of the line of travel of another electro-magnet 27, similar to the magnet 25, and
also having its pole pieces provided with iron wire brushes 26. This magnet 27, is
placed at or near the rear end of the motor car or car truck, and, when over the
blocks 24, these latter become, temporarily, extended pole pieces thereof and
attract the bar or armature 10. Since the switch lever is pivoted centrally, the
lifting of the armature 10, by the magnet 27, will depress the armature 9, thus
moving the jacks from between, and out of contact with the brushes, thereby
breaking the circuit between the blocks 22, and the source of current supply. The
limit of movement of the switch lever in either direction around the pivot is
determined by two stops 28, 28, one in the path of the armature 9, and the other
in the path of the armature 10, the said stops rising from the base plate 6.
Current for feeding the motors on the car and for energizing the travelling
magnets is collected in any suitable manner from the contact blocks 22, but
preferably by means of collectors hereinafter described.
A switch constructed as described will operate under the action of the travelling
ין
I

page_text: magnets to close the circuit, when the car reaches the switch box and to open the
circuit as the car leaves it. In order that the switch levers may be moved in either
direction with the requisite speed and with the exertion of the minimum amount of
power, they are balanced on their pivots as accurately as is practicable. Such a
balanced switch lever is easily moved about its pivot by shocks and jars caused by
the ordinary surface travel. To obviate the danger arising from the accidental
closure of the circuit, in which case the exposed contacts would become charged,
each switch is provided with a lock that will act automatically to hold the switch
in the open position when not covered by a car, and which will be operated
to unlock the switch by the forward magnet of a motor car when it reaches the
switch box.
The
This lock consists essentially of a gravity latch mounted on the switch lever and
capable of being lifted by magnetic attraction from a motor car, and of a fixed
catch in the switch box in the path of the latch. The latch is composed of an iron
plate 29, having near each end an arm 30, projecting at right angles therefrom and
terminating in a beveled and shouldered head or hook 31. This plate 29, which
performs the function of a supplemental armature covers the upper face of the
armature 9, and is pivoted to the said armature by means of pins passed through
the arm 30, and through ears 32, formed on the outer side of the armature 9.
two arms 30, extend downward past the armature, and, in the path of the
shouldered heads 31, are similarly shaped catches 33, erected on the base plate 6.
The latch bas a limited movement about. its pivot, the extent of movement in one
direction being determined by lugs 34, on the arms 30, which lugs engage the side
of the armature 9, and in the other direction by the catches 33, the upper face of
the armature 9, being slightly inclined or beveled to give the supplemental
armature 29, sufficient range of movement toward it. The supplemental arma-
ture 29, overbalances the arms 30, so that its tendency is to throw the lower ends
of the arms outward. When the switch is in the closed position, the beveled edges
of the heads or hooks 31, of the arms 30, and the beveled edges of the catches 33,
are in engagement, and when the switch is moved toward the open position, the
heads 31, ride downward past the beveled faces of the catches until the shoulders
on the heads 31, pass the shoulders of the catches. The supplemental armature 29,
then immediately forces the heads 31, under the shoulders on the catches, where
they are held by gravity, thus effectually locking the switch lever against any
force tending to move it toward the closed position, except a force which will lift
the supplemental armature 29, thus moving it on its pivot and drawing the heads 31,
from under the catches 33.
When the electro-magnet 25, reaches a switch box, it attracts the supplemental
armature 29, thereby moving the hooked ends 31, of the arms 30 from under the
catches 33, thus releasing the switch lever. The armature 9, being unlocked,
is then immediately drawn upward by the magnet, and the jacks 13, close the
circuit to the contact blocks. The switch lever is held in the closed position by
the friction of the members of the switch, as before explained, and this position is
maintained until the magnet 27, acts upon the armature 10, and opens the switch,
in the manner before described. As the switch lever is moved toward the open
position, the movable member of the latch descends toward the catches until the
heads 31, ultimately engage under the said catches and thereby lock the switch
lever against any force tending to close the switch, until the lever is again unlocked
by the passage thereover of the magnet 25, on a motor car.
The switch box and switch shown in Figs. 4 and 5, is similar in principle to that
shown in Figures 1, and 3, but differs therefrom in several particulars. The
cover of the switch box, shown in Figs. 4 and 5, is flush with or projects slightly
above the surface of the road bed and is ribbed to form a foot-hold for horses.
The contact blocks 22, and the blocks 24, are omitted, and the armatures of the
switch lever and of the latch are acted upon by the electro-magnets, without the
intervention of supplemental pole pieces, and through the cover of the switch box..
The standards 7, and stops 28, as well as the catches 33, are all cast in one piece

page_text: and fastened to the bottom of the switch box by screws, or otherwise, with an
intervening cushion plate 341, the whole structure being so formed as to constitute
a chamber enclosing the switch and forming a support for the switch lever. The
pivot bolt or rod 8, is made fast to the cross pieces 11, of the switch lever
by pins 35, at points exterior to the switch containing chamber, and, secured
centrally to this rod, which passes through suitable bearings formed in the end
walls of the said chamber, is a downwardly projecting arm 36, having its lower end
bifurcated to receive the insulating block 12, having at its lower end a jack 13.
This jack is moved to and fro by the armature lever through an arc described
about the axis of the rod 8, and in the path of this jack are metal brushes 14, 15,
(of which only one is shown) fast upon opposite sides of an insulating block 37,
housed in, and fixed by pins 371, to the contracted upper end of a lateral
extension 38, of the switch-containing chamber. Both brushes are secured to the
block 37, by bolts 39, insulated from the brushes by interposed bushings 40.
These bolts also serve to secure to the brushes in electrical contact therewith,
plates 41, constituting the terminals, one, of the branch conductor 18, and the other,
of another conductor 42, leading to a section 43, of an exposed feeding conductor in
the road bed (see Fig. 7,) from which current is collected in the usual manner and
fed to the motors on the car, the return to the generator being through the rails as
usual. The conductors 18 and 42, enter the switch box through a neck 19¹ formed
on the extension 38, of the switch containing chamber, and extending through
a perforation in one of the sides of the box 1.
The motor car is represented in Fig. 8, by a simple diagrammatic view of its
truck 44. Upon this truck are two motors 45, 45, (shown separated from the truck
in the diagram), one of the motors being provided with the usual starting coil 46 ;
the car is also provided with the ordinary circuit controller 47.
Depending from the motor car truck are the two electro-magnets 25, 27, the
magnet 25, being located at or near the front end of the car truck and the
magnet 27, at or near the rear end of the same as before stated. The magnets 25,
and 27, each have their pole pieces provided with downwardly projecting iron
brushes 48, which, as the magnets pass over the blocks 22, 24, make contact
therewith, so that the said blocks constitute, for the time being, extended pole
pieces of the magnets.
Directly behind the magnet 25, and in line therewith, there is mounted on the
car truck an extended contact device for collecting the current from the blocks 22,
and delivering it to the motor or motors on the car.
This contact device consists of a number of brushes 49, close to the surface of
the road hed, and preferably formed of phosphor bronze wires fixed to plates 50.
Pairs of vertical guide rods 51, passing through suitably spaced holes in the two
sides of a long, narrow, rectangular frame 52, fastened in any suitable manner to
the car truck frame are secured at their lower ends to, and support the brush
plates 50. Surrounding each rod 51, is a helical spring 53, confined between the
under face of the upper side bar of the frame 52, and a washer 54, on the rod 51 ;
this washer rests on a pin 55, fixed in the rod al. The tendency of the springs 53
is to force the collecting brushes 49, downward to the road bed, but this movement
is limited by the pins 55, engaging the upper face of the lower side bar of the
frame 52.
It will be apparent without further explanation, that the brushes will readily
yield to and ride over any obstruction on the road bed that they may come in
contact with. In their normal position, the lower ends of the brushes are slightly
below the upper surface of the contact blocks 22, and the edges of the latter are
slightly beveled. On reaching these blocks, the wires of the brushes will yield
somewhat because of their elasticity and the brushes will also rise bodily against
the action of the springs 53; this will insure excellent contact between the brushes
and the blocks 22. The current flowing from said blocks will be conveyed from
the brushes through the rods 51, to the frame 52, either directly, or by auxiliary
flexible conductors, not shown.

page_text: This frame 52, is connected by a conductor 56, to the controller 47, by which
latter the circuit is completed to the motor or motors, and from this controller a
conductor 57, extends to the truck frame 44, through the wheels of which the
circuit is completed to the rails, and thence back to the generator. A branch
conductor 58, coming from the conductor 56, extends to the magnet 25, the normal
coils 25, of which are connected in series with the normal coils 271, of the
magnet 27, by a conductor 59, the circuit being completed from the latter by the
conductor 60, which is connected with the conductor 57, and includes an electro
magnet 61, the purpose of which latter will presently appear. The normal
or main coils of the magnets 25 and 27, are thus in shunt around the motors 45,
and circuit controller 47, and are therefore unaffected by the running of the car.
There is a sufficient number of brushes 49, to extend from one switch box to the
next in order so that the circuit to the motor from the main conductor 20, will
always be completed through a switch box before the last brush 49, has left the
blocks 22, of the preceding switch box.
During the normal operation of the car, the magnets 25 and 27, are energized by
the branch 58, 59, 60, of the main circuit upon the car. It sometimes happens that
this circuit becomes broken, either by the burning out of the main coils of the
magnets or from some other cause, and the magnets, being thereby de-energized,
fail to operate the underground switches; the car therefore quickly comes to a
stand-still because no current is supplied to the motors. To guard against such a
contingency each magnet is wound, in addition to the high resistance main coils,
with local circuit coils 25", 27, of low resistance, indicated by the heavy lines in
Fig. 8. These local circuit coils of the two magnets are connected in series by a
conductor 62, and the coils 25" are connected by a conductor 63, to one terminal
of a storage or other battery 64 on the car, and the coils 27", are connected by a
conductor 65, to a hand switch 66, in the path of which is a contact block 67 which
latter is connected to one plate 68, of a jack-knife switch, while the other plate 69,
of this switch is connected by a conductor 70, to the other terminal of the
battery 64. A switch lever 71, is arranged with one end adapted to bridge the
two plates 68, 69, towards which it is urged by a spring or springs 72; the other
end of the switch lever is provided with a head 73, constituting an armature for the
magnets 61.
In the normal operation of the system the magnet 61, is energized by the line
current, and therefore, the armature 73, is attracted to this magnet against the
action of the spring 72, thereby breaking the circuit between the plates 68 and 69.
When, however, the main circuit is broken either accidentally or purposely, the
armature 73, is no longer attracted by the magnet 61, and the spring 72 draws
the switch lever 71, into contact with the two plates 68, and 69, so as to bridge the
same. If, under these conditions, the local circuit is closed by moving the switch 66,
upon the plate 67, the current from the battery 64, will immediately energize the
magnets 25, 27, and the latter will operate the underground switches when moved
over them.
The switch 66, is utilized for energizing the magnets 25, 27, by means of the
local circuit, when the car is taken out of the car house preparatory to starting on
a trip. As soon, however, as an underground switch is closed by the magnet 25,
energized by the battery 64, and the first of the brushes 49, comes in contact with
one of the blocks 22, the main magnet circuit is closed. The magnet 61 being
thereby energized, automatically breaks the local circuit by attracting the
armature 73, and the latter is held in this position so long as the main circuit to the
magnets 25 and 27, remains closed. During the time the car stays upon the road
the switch 66, is allowed to remain in the closed position, so that, should the main
circuit through the magnets 25, 27, be broken, as for instance, by the latter
burning out, the local circuit will be immediately established and the magnets 25,
and 27, will continue to operate the underground switches as before, thereby
ensuring the proper operation of the motor car even under the extraordinary
conditions noted.
:

page_text: The secondary battery 64, may consist of but few cells, since it is only necessary
that the magnets be energized thereby, (should the main magnet circuit be broken)
until the car again reaches the. terminal station where the damage can be
repaired.
However, since the switch 71, controlling the local circuit for the magnets 25
and 27, is operated automatically to close the said circuit when a break occurs in
the main magnet circuit, the car will operate as though no accident had happened,
and unless the motor-man be made aware of the fact that the main coil circuit has
been broken, he would put the car upon a second trip without repairing the injury
sustained, and the secondary battery upon which he is now drawing might become
exhausted while the car is still on the road. To avoid this, I provide means for
notifying the motor-man of the accident that has occurred. These means are
shown in Figures 10 and 11, which also illustrate in detail the automatic controller
for the local energizing circuit already briefly described with reference to
Figure 8.
The magnet 61, as shown in these figures is of the horse-shoe type and the
switch lever 71, consists of a yoke piece pivoted to laterally extending studs 74,
projecting from the upper end of a post 75. The lever 71, terminates at one end.
in the head 73, constituting the armature for the magnet 61, and at the other end
in an arm 76, carrying a U-shaped conducting strip or jack 77, adapted to enter
between and bridge the two plates 68, 69..
Fast to the post 75, and projecting laterally therefrom is a block 78, of insulating
material, to opposite sides of which the plates 68, 69, are secured in any suitable
manner, as for instance, by insulated bolts 79, which pass through the block and'
plates 68, 69, and serve to secure to the latter the terminal plates 80, fast on the
ends of the conductors leading to the plates 68, 69.
In the structure illustrated in Figs. 10 and 11, two springs 72, are shown.
The post 75, has a stem 81, projecting above the studs 74, and to the top of this
stem is secured a gong 82, in the path of a striker 83, projecting from the underside
of the armature 73, midway between the two coils of the magnet 61. The striker
is so arranged that when the armature is released by the magnet 61, and is thrown
upward by the springs 72, it will strike the gong 82, thus giving an audible signal
that will notify the motor-man of the fact that the main circuit through the
magnets 25 and 27, has been ruptured and the local circuit has been closed. Thus
he will be warned to turn his car in for repairs at the end of the trip.
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 me
by my foreign correspondent, I declare that what I claim is:
1. In an electric railway, the combination with a main or supply conductor and
feeding conductors or contacts, of switches for coupling the main and feeding
conductors, each switch being provided with a rocking switch lever, extending
transversely to the line of travel and having an armature on each side of its pivot
and two travelling electro-magnets, one acting on one armature and the other on
the other armature of the switch levers, substantially as described.
2. In an electric railway, the combination with a main or supply conductor and
feeding conductors or contacts, of switches for coupling the main and feeding
conductors, each switch being provided with a balanced switch lever extending.
transversely to the line of travel and having an armature on each side of its pivot,
and two travelling electro-magnets, one acting on one armature and the other on
the other armature of the switch levers, substantially as described.
3. In an electric railway, the combination with a main or supply conductor and
feeding conductors or contacts, of switches for coupling the supply and feeding
conductors, each switch being provided with a rocking switch lever and a gravity
latch for locking the switch in the open position and travelling electro-magnets
operating the switch to close and open the circuit and also operating the latch to
unlock the switch, substantially as described.

page_text: 4. In an electric railway, the combination with a main or supply conductor and
feeding conductors or contacts, of switches for coupling the supply and feeding
conductors, each switch being provided with a latch for locking it in the open
position and travelling electro-magnets unlocking and operating the switch,
substantially as described.
5. In an electric railway, the combination with a main or supply conductor and
feeding conductors or contacts, of switches for coupling the supply and feeding
conductors, each switch being provided with a switch lever having an armature on
each side of its pivot and a lock composed of a latch carried by the switch lever
with a supplemental armature covering one of the armatures of the switch lever
and fixed catches in the path of the latch, and travelling electro-magnets
operating the latch and switch lever by magnetic attraction, substantially as
described.
6. In an electric railway the combination with a main or supply conductor,
exposed contact blocks arranged at intervals along the road bed, inagnetically
operated switches for coupling the main conductor to the contact blocks, travelling
electro-magnets for operating the switches, and a collector, independent of the said
magnets, bridging the contact blocks, the circuit connections of which are controlled
by two successive switches, substantially as described.
7. In an electric railway, the combination with a supply conductor, exposed
contacts on the road bed, and magnetically operated switches for coupling the
exposed contacts to the supply conductor, of travelling electro-magnets each having
two windings, one included in a branch of the line circuit and the other in a local
circuit, and a switch controlled by the line circuit branch for closing the local
circuit when the line circuit through the magnets is broken, substantially as
described.
8. In an electric railway, having underground switches adapted to be operated by
magnetic attraction from a motor car, switch operating magnets, on the motor car,
having two windings, one included in a branch of the main or line circuit and the
other in a local circuit on the car, a switch for closing the local circuit controlled
by the line circuit branch, and a signal controlled by the switch on closing the local
circuit, substantially as described.
9. In an electric railway having underground switches adapted to be operated by
magnetic attraction from a motor-car, switch operating magnets, on the motor car,
having two windings, one included in a branch of the line circuit and the other in a
local circuit upon the car, a switch for closing the local circuit controlled
by the line circuit branch and a bell controlled by the switch, substantially as
described.
10. In an electric railway, travelling electro-magnets for operating circuit
closing and opening devices in the road bed, the coils of the magnets being charged
by a branch of the line current, a normally open local circuit including other coils
on the magnets, with a local source of current for the same and a switch for
closing the local circuit controlled by the line circuit branch, substantially as
described.
11. In an electric railway, a collector comprising a continuous rigid metallic
frame, and a series of independently spring controlled brushes mounted in the
said frame in electrical connection therewith, substantially as described.
12. A current collector for an electric railway, consisting of an elongated rigid
metallic frame mounted on the car, a series of independently spring actuated guide
rods mounted in the frame, and metallic wire brushes secured to the guide rods,
substantially as described.
WM. P. THOMPSON & Co.,
Agents.