Improvements in and relating to Electric Railways, and Apparatus therefor.
Year: 1895

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Electric Railways, and Apparatus
therefor.
I CARL FRIEDRICH PHILIPP STENDEBACH, Electrician of Weissenfelser-
strasse 32, Plagwitz Leipzig in the Empire of Germany do hereby declare the
nature of this invention to be as follows:-
This invention relates to electric railways having an underground supply of
current to the section in which the car is moving, and the improved contact device
employed in this invention is designed to be completely protected against adverse
influences whether mechanical atmospheric and especially against damp, and
moreover is so made that the current is only then present in the apparatus when
a car to be driven is in proximity to or above the apparatus.
In the middle of the railway line between suitably arranged protecting rails a
contact rail is located, which in its longitudinal direction is composed of a number
of separate lengths, which according to the length of the cars are arranged with
intervals of from 3 to 4 meters between them.
On this rail run two contact pressure rollers, carried by the carriage, which
convey the current to the motor. This contact rail is either arranged so as to
be movable in a vertical plane or so as to be rigid, according as the actuation of
the contact is effected mechanically or by electric current.
Beneath the ends of the rail there is a downwardly movable contact pin which
is caused to complete the circuit either by the rail which is moved downward by
the car or the contact pressure roller or by means of a special contact piece.
The contact-point itself is located in a movable iron cylinder which is safely
closed and safeguarded against all outer influences and into said cylinder an
extension from the electric cable is led.
The co-operation of the contact rail influenced by the car with the contact
apparatus itself will be understood from the following description.
The car passing over the line is always in touch with one section of the contact
rail before leaving the other section.
The current is supplied to the different sections by means of the mechanically
or electrically actuated contact apparatus.
The contact apparatus are fed by an underground cable of a suitable cross
section and mounted with iron hoops."
The contact apparatus are arranged in the following manner and will act in the
following manner when worked mechanically.
The apparatus consists of a chamber open above made of cast iron which is
mounted upon a cast iron plate with the interposition of an insulating layer of
tarred paper or other suitable material.
The base plate is likewise fixed with an intervening insulating layer upon a
masonry foundation.
At its upper end the chamber is closed by means of a cover which latter, where
apparatus with electric actuation are concerned is in addition magnetically insulated
from the chamber walls, by means of a ring of zinc of appropriate thickness, or
which cover may also be made of yellow brass.
The fixing of these parts is in mechanically actuated apparatus, effected by
means of iron screws, and in electrically actuated apparatus by brass-screws.

page_text: Directly above the apparatus the contact and protecting rails are mounted on an
insulating wooden base either directly or on a dome shaped piece of cast metal
bridging over the chamber.
A metal socket or sleeve is provided which passes through the insulating wooden
base and which in its lower part consists of two parts connected by flanges the
lower being screwed on the cover of the chamber with an intervening insulating
layer.
Through the bottom of the chamber the insulated extension coming from the
cable is passed and thoroughly tightened by means of nuts or bushes.
This cable extension is passed upward to about one half of the height of the
hollow space of the chamber and carries at its end a mercury or spring contact.
This contact on its part is surrounded by a conical or other wrought iron bell
which reaches nearly down to the bottom of the chamber.
At its upper end this bell is solid and through it passes an insulated iron contact
pin fixed therein. Said contact pin passes through a bush in the centre of the
cover, is likewise insulated from the latter and passes further through the bore of
the cast iron sleeve before mentioned and its semi-circular head rests against the
contact rail being kept in this position in mechanically actuated railways by a
spiral or other spring arranged beneath the bell, and in electrically actuated
railways by means of a flat spring arranged beneath the cover plate and the pin.
The bell is guided by means of projections inside the chamber. At its lower end
the bell is hermetically sealed in mercury and a thin caoutchouc disk may connect
the top of the bell to the chamber wall, this disk serving at the same time as a
packing between the chamber and its cover.
Above this packing an outflow or outflows are arranged in form of a downwardly
bent tube.
In railways with mechanical actuation of the contact mechanisms a contact wheel
is arranged in front and one at the back of the car which under strong spring
pressure, press on to the contact rail. The latter will sink and thereby the pin in
the interior of the contact mechanism dips into the mercury, or the spring contact
respectively closes.
The current passes through the pin into the contact rail, through the wheel to
the motor and through the rheostat to the rails proper serving as return conductors
until the carriage leaves the section and comes into contact with the next.
As soon as this latter takes place the former contact rail rises owing to the
pressure of the spring and the section is without current. Thus completion of
circuit takes place on every section as the carriage passes onto it whilst the whole
of the remainder of the line is without current.
If the contact mechanism is to be actuated electrically, the contact rail is
stationary and its end is fastened to the sleeve in which the contact pin passes.
The hollow space around the chamber is provided with a compound winding, a
spiral of thin copper strip located in a secondary circuit between the contact pin
sleeve and the return conductor placed in circuit with a rheostat corresponding
with the applied tension is wound upon the wall of the chamber and insulated and
waterproofed.
Over this coil is wound the main current coil which is only passed by that
quantity of current necessary for moving one car this coil commencing from the
cable and its end passing to the mercury or other contact.
Both coils surround the chamber in the same direction and an exterior jacket or
covering usually of cast iron is placed over them which, through a filling hole (to
be closed by a screw is filled up with a suitable insulating material so that said
coils are fully protected against damp and other influences.
Before the car has come into contact with the contact pin or its projecting head
respectively, no current whatever will circulate in the secondary circuit, since
no difference of potential exists between the contact rail and the return conductor.
It is not until the car passes over the rail whereby this contact is made, that
rail becomes electro-positive and then immediately the secondary circuit will

page_text: commence acting and will, in co-operation with the working wire or main current
coil draw downward and hold the iron bell until the car has passed off the
section.
When the coil for the main current becomes thus inert, the secondary circuit
is not capable of resisting by itself the spring which acts in the contrary direction
return the bell. Thus the contact is broken and the supply of current thus
ceases to that section.
Further the rheostat on the car must be arranged so that by the same turning of
the contact lever by which the driver breaks the current, the breaking of the
current is preceded by the insertion of a resistance between the induction and the
return circuit which corresponds to the lowest working capacity of the main
current coil, so that at any point of the line an immediate starting can be effected
and without any breaking of the contact taking place.
At terminal stations this rheostat should be entirely disconnected and the car
brought to a standstill upon a contact pin or said contact pin must by means of a
suitable lever be pressed down at the terminal station before the car starts.
The inducting effect of the compound coil upon the bell may be materially
increased by making the chamber of yellow brass which latter arrangement results
in greatly decreasing the dimensions of the apparatus.
In railways with one line and with electric actuation such contact apparatus
should be arranged between about every 15 yards length of the rails at the
beginning and end of each contact rail whilst in double liued railways in
direction of the movement one only is necessary to each section.
In railways with mechanical actuation there should be in all cases two contact
mechanisms necessary for each 15 yards including the interval of 4 yards existing
between the sections.
Dated this 15th day of January 1895.
HERBERT HADDAN & Co.,
Agents to the Applicant.
COMPLETE SPECIFICATION.
Improvements in and relating to Electric Railways, and Apparatus
therefor.
I CARL FRIEDRICH PHILIPP STENDEBACH, Electrician, of Weissenfelser-
strasse 32 Plagwitz-Leipzig, in the Empire of Germany do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly ascertained and described in and by the following statement :-
This invention relates to electric railways having an underground supply of
current to the section on which the car is moving and the improved contact device
employed in this invention is designed to be completely protected against adverse
influences whether mechanical or atmospheric and especially against damp, and
moreover is so made that the current is only then present in the apparatus when a
car to be driven is in proximity to or above the apparatus.
The invention is shown in the accompanying drawings Sheets 1-3 Figs. 1-22
which represent the improved apparatus for electric railways in which the current
is supplied by a subterraneous conductor to the spot where the carriage is at any
given moment by the contact rails or partial conductors over the contact wheels to
the motors of the car.
From the latter the current passes through the running wheels of the car and
from here along the rails which serve as a return conductor to the place where
it is generated. This circuit can be seen in Fig. 20, where M"" represent the
motors.

page_text: The contact rail is fastened between the protecting rails by means of porcelain
insulators J Fig. 18, and at each end of a contact rail it is strengthened by a
porcelain block J Fig. 19.
The above mentioned insulators J' are supported by bolts S₁ which at the same
time hold together the channel formed by the protecting rails Fig. 18.
The whole of the apparatus is fitted up to the street level.
The contact rail S is divided into sections Fig. 19, in such a manner, that the
car passing over the line, is always in touch with one section before leaving the
previous section.
The current is supplied to the different sections by the contact apparatus fitted
directly under the contact rail, and only during such time as the car is over the
particular section.
This is shown in Figs. 21 and 22 where X is the generator and Y the carriage
motor. The current is in the direction of the arrows. RW is the regulating
resistance and E W an extra resistance brought into circuit on the stopping of the
car so as to avoid breaking circuit.
The contact apparatus are fed by an underground cable K¹, well insulated and of
suitable cross section, Fig. 19.
The contact apparatus consists of a chamber A open above, made of cast iron,
which is mounted on a cast iron plate B with the interposition of an insulating layer
of tarred paper. The base plate is likewise fixed with an intervening insulating
layer upon a masonary foundation C Fig. 1.
At its upper open end the chamber A is closed by means of a cover D.
The fixing of both parts is effected by means of brass-screws.
Directly above the apparatus the contact and protecting rails are mounted, with
intervention of an insulating layer l, either directly, or on an insulating dome-shaped
cast-iron case T (Figs. 5 and 6).
In the latter case, the contact slide E has fixed to it a protecting socket or
sleeve E' which passes through the insulating layer 1, and consists in its lower part
of two combined and removable annular halves, screwed to the cover D with an
insulating layer between them and between the lower one and the cover D,
Figs. 5 and 6.
Another form of construction of the contact slide E can be seen in the drawings
Figs. 8, 9 and 10 where the contact slide is secured by means of eight porcelain
insulators J on the two cast iron hollow plates U resting on the case T.
The contact slide has fitted at its sides and cast with it in one piece two
protecting side parts e which form to the right and left with the body of the slide
a sort of channel, which prevents snow and water from getting between contact
slide E and protecting rails Sch. Figs. 8, 9 and 10.
The water intruding in this spot, will get into this channel and run off in front and
behind into the cavities where the contact apparatus stands, whence it may be
carried to the drains.
With this form of construction of the contact slide E, the above mentioned
protecting socket or sleeve E' will not be required, instead of which the slide E
will have an oval opening into which the insulated socket piece E' penetrates
Fig. 10.
The electrical connection between slide E and socket E' is obtained by means
of a leaden wire y, serving at the same time as safety-cut-out as shown in Fig. 19.
On the spot where the socket E¹ is screwed to the cover D, the latter has a
depression, which, after the socket has been screwed on, is filled with asphalt, to
prevent any water flowing over the apparatus from forming a circuit between the
socket E and the earth Fig. 10.
This loose arrangement between slide and apparatus has the advantage of
permitting the slide to take any required position on inclined roads and allows of
always mounting the apparatus exactly vertically.
Through the bottom of the chamber A is passed the insulated extension K
coming from the cable K' fastened by means of nuts M M and thoroughly

page_text: tightened against water penetrating from below, by an interposed packing of
leather and metal rings, Fig. 1.
This extension K is surrounded by a metal protecting cover for the purpose of
giving it greater stability.
The cable extension K is passed upwards to about one half of the height of the
hollow space of the chamber and carries at its end a mercury contact cup G
(Figs. 5 and 6,) or a spring contact G' (Figs. 10, 11 and 13).
The contact G or G on its part is surrounded by a conical wrought-iron
cylinder F, which reaches nearly down to the bottom of the chamber.
At its upper end this iron cylinder is closed by a plate through which passes
and in which is fixed an insulated iron contact-pir. H.
Said contact pin passes through the centre of the cover D, from the latter also
through the piece d which is made of brass, insulated and screwed to the cover D;
it passes further through the bore of the contact-slide E and its semi-circular
head rests in a corresponding groove of the contact-slide E (Fig. 2) where it can
move up and down.
The head and with it the iron cylinder F, connected with the contact pin, are
supported by the spring situated under head h, Fig. 2.
The iron cylinder F is guided inside the chamber A by means of four equally
spaced opposed projections 6 Figs. 1 and 4.
At its lower end the bell F is hermetically sealed in mercury Q Fig. 1, into
which it penetrates for about 20-30 m/m after the manner of a diving bell, and is
thus perfectly secured against all outward influences of damp &c. 'It is moreover
sealed by a thin caoutchouc disk N which serves at the same time as a packing
between the chamber A and its cover D.
Above this packing an outflow or outflows may be arranged in form of a
downwardly bent tube V Fig. 1, which is screwed by one end directly to the
cover D whilst the other downwardly bent end is fitted with an anti-return-valve v
Fig. 17, in such a manner, that this tube will be opened by the pressure of the
water collected in tube V, but any water trying to penetrate from outside by
valve will only help to close it, which is also done by a weak spiral spring fil
Fig. 17, thus no water can get into the apparatus from this side.
V
111
The hollow space around the chamber A is provided with a compound winding R;
a spiral of thin copper strip located in a secondary circuit between the contact pin
sleeve E and the return conductor L Fig. 1 placed in circuit with a rheostat
corresponding with the applied tension, is wound upon the wall of the chamber A,
with its beginning towards contact sleeve E, and with its other end connected
with the return_conductor or with the rails respectively, and waterproofed by an
outer covering P.
This covering P, made of cast iron, not only protects the coil against outer
influences but also serves as a return conductor for the current.
Over this coil is wound the main current coil which is only traversed by the
current necessary for moving one car, this coil commences from the cable K¹
and surrounds the chamber in the same direction as the other coil, and passing
through the outer covering P ends in the contact G or G¹.
The secondary coil has to be measured so as to furnish of the magnetising
work (when the car is empty and running on a horizontal track) necessary for
attracting and retaining the iron cylinder F in the hollow space of the chamber A;
whilst the rest of the magnetising work may be done by the main coil.
The purpose of the employment of the secondary coil is that the main coil may
be given fewer windings so that, on the one hand the fall of potential in the main
coil with full load may be as small as possible and on the other hand the whole
apparatus may be the smaller in size. Lastly this arrangement permits of the use
of any desired method for regulating the motor, whether by insertion of resistances
in the main circuit or by the putting in and out of circuit of the electromagnet
coil since by the use of this secondary coil the strength of the main current may
vary within very wide limits as the main current has only to supply a quarter of

page_text: the magnetising work. The secondary coil is thus interpolated directly between
the out and return leads so that its magnetising force may remain always the
same under different loads on the motor, whereas if it were in the motor circuit it
would be dependent on the load on the motor which as above said, should be
avoided.
Before the car has come into contact with the contact pin h or its projecting
head respectively, no current whatever will circulate in the secondary circuit, since
no difference of potential exists between the contact slide E and the return
conductor L.
Only when the contact G is closed, that is to say when the head or his
pressed down by the contact wheels r of the car passing above, Fig. 19; the
contact slide E and connected with it the rail S will become electro positive,
and then immediately the secondary circuit will commence acting, and will, in
co-operation with the working wire or main current draw downward and hold the
ion bell F until the car has passed off the section.
As then the coil for the main current becomes inert, the secondary circuit is not
capable of resisting by itself the spring f which acts in the contrary direction,
thus the contact is broken and the supply of current ceases to that section.
As shown in Figs. 5, 6 and 10 the contact pin H may be fitted loosely to the
head
.
In this case may be fixed as a one-armed lever and turnable in the contact
slide E.
The spring may be chosen in any suitable size, as the release of the contact is
obtained independently of spring f' by the spiral spring f" bearing in the socket E',
which spiral spring has therefore only to overcome the weight of the cylinder F
and the resistance of the secondary current, and no frictional resistance resulting
from the insertion of street refuse and dust between head and slide E has to be
overcome, which resistance might occasion an uneven acting of spring f¹ Fig. 1
and in this manner an easy working when putting in and out of circuit is insured.
With the construction of the centre piece of the chamber A as shown in
Figs. 5, 6 and 10 the reducing influence of the compound winding of the cylinder F
is considerably increased as the magnetic current is forced to take its way from.
below upwards through the iron cylinder and to form the contact in the covering P,
when the iron parts of chamber A will have to be considered as poles.
By this latter arrangement considerable space and therefore also expense may
be saved which would result in a greater cheapness of the whole apparatus as may
be seen by comparing the contact and protecting rails to the whole apparatus in.
Figs. 1 and 10, which latter represents the apparatus with the rails in their actual
condition in about th of natural size.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A contact apparatus for electrical railways with underground supply of
current and divided conductor in which is employed a contact device S, fitted
between two protecting rails Sch, of a particular form, below which contact device
is located, in a chamber hermetically sealed against all outward influences, a
mercury contact G or a spring contact G¹ which is actuated as soon as the contact-
wheels of the car, passing above, press down the head / or h¹ working in connection
with the contact pin H.
2. The form of construction of the apparatus described in Claim 1, in which, to
produce the contact, the chamber A and the iron cylinder F are electrically
actuated by the compound winding R of the main and secondary currents, circuit
being formed by a short downward movement of the contact pin H in connection
with the head h or h¹ so that by the action of the main and secondary currents, the
iron cylinder F, containing the contact G or G¹ and protected by caoutchouc
ring N and mercury contact Q against all outward influences, damp &c., will be

page_text: kept down and thus the circuit maintained until the contact wheels of the car have
left the section.
Dated this 14th day of October 1895.
HERBERT HADDAN & Co.,
18 Buckingham Street, Strand, W.C., Agents to the Applicant.