Apparatus for Supplying Electrical Energy to Tramcars from Underground Conductors.
Year: 1895

page_text: Date of Application, 6th Sept., 1895
Complete Specification Left, 26th May, 1896-Accepted, 27th June, 1896
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of 94 Markgrafen-
Strasse, Berlin, Electrical Engineers.]
Apparatus for Supplying Electrical Energy to Tramcars from
Underground Conductors.
We, SIEMENS BROTHERS & Co., LD., of 12 Queen Anne's Gate, Westminster,
in the County of London, Electrical Engineers, do hereby declare the nature of
this invention to be as follows:-
The existing constructions of underground apparatus for the supply of electrical
energy to electric tramcars are comparatively expensive as they all necessitate the
formation of a spacious underground channel with an open slot at the top.
Various arrangements have been proposed from time to time for obviating this
by means of a system of sectional conductors, but without practical success, owing
mainly to the fact that the connection of the sections of the conductor with the
main circuit was effected by the unreliable action of electromagnets, which in
addition, rendered a complicated underground apparatus necessary.
The present invention relates to au improved construction of the sectional
conductor system which avoids the disadvantages of complication and unreliableness
of the previously proposed arrangements. It consists mainly in the following.
Through holes in the longitudinal groove of the tram rail project the upper ends
of rods the lower ends of which are connected to underground levers which on the
depression of the rod by the wheels of a passing tramcar are made firstly to raise a
sectional supply conductor above the surface of the road so as to make contact
with a contact bar on the underside of the car, and secondly to cause such sectional
conductor to be coupled up with the main supply circuit.
For practically carrying out this construction various arrangements may be
employed; the following is the one preferred. A cast iron box closed by a
cemented cover contains a horizontal two armed lever, the shorter arm of which is
acted upon by a rod rising vertically through a hole in the groove of the tram rail,
so as to be depressed by the flanges of the passing wheels.
The long arm of the lever supports by a ball and socket joint a sectional supply
conductor which can slide up and down between insulating guides, through a hole
in the top of the box so that by the depressing of the short arm of the lever, the
long arm raises the sectional conductor from a position below the surface of the
roadway, to such a height above it, that on the passage of a tramcar, a contact
rail on the underside thereof will slide in contact with the sectional conductor.
As the latter is raised, the lower part thereof within the box comes into contact
with a contact piece carried by an insulator and connected by a lead with the
underground main circuit. The long arm of the lever is also connected to a second
vertical rod that is raised above the roadway by the above described motion of
the lever, so that on a downward projecting roller at the rear end of the tram car
passing over this rod, it is depressed thereby and thus brings the before mentioned
parts back to their original position.
Boxes containing the above described apparatus are arranged at short distances
apart along the line and the contact rail of the car is so formed as to maintain a

page_text: good contact with one sectional supply conductor until it makes contact with the
succeeding one.
Dated this 6th day of Sentember 1805
ABEL & IMRAY,
Agents for the Applicants.
Apparatus for Supplying Electrical Energy to Tramcars from
Underground Conductors.
We, SIEMENS BROTHERS & Co., LD., of 12 Queen Anne's Gate, Westminster
in the County of London, Electrical Engineers 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 :→
The existing constructions of underground apparatus for the supply of electrical
energy to electric tramears are comparatively expensive as they all necessitate the
formation of a spacious underground channel with an open slot at the top.
Various arrangements have been proposed from time to time for obviating this
by means of a system of sectional conductors but without practical success, owing
mainly to the fact that the connection of the sections of the conductor with the
main circuit was effected by the unreliable action of electromagnets, which in
addition, rendered a complicated underground apparatus necessary.
The present invention relates to an improved construction of the sectional
conductor system which avoids the disadvantages of complication and unreliableness
of the previously proposed arrangements, the apparatus being constructed with a
view to the greatest possible simplicity and strength of the several parts, while not
only the bringing into action but also the putting out of action thereof is effected
by forcible means.
The arrangement for these purposes is as follows:-The rim of a road wheel of
the vehicle is made to depress the end of a rod projecting up through a hole in the
groove of the rail.
This rod actuates a two armed lever by means of which on the one hand a supply
contact piece is raised up through an opening in the pavement, and on the other
hand, contact is made with the main circuit whereby the supply contact piece is
included in the circuit.
A contact bar carried on the underside of the vehicle is made to slide over the
contact piece, which bar is so arranged as always to be simultaneously in contact
with two contiguous contact pieces. After the bar has passed off such contact,
this is depressed again by a second upward projecting rod acted upon by a roller
carried by the vehicle.
The construction of the said apparatus is shewn on the accompanying drawing,
in which Figure 1 shews a vertical section and Figure 2 a plan. In a cast iron
box A closed by a cover B is situated a two armed lever a the short arm of which
supports a rod that projects up through a slot in the groove of the rail C, so that
on the depression of the rod by the wheel of a passing vehicle, the short arm of
the lever a will be depressed, and the long arm raised up.
This long arm carries a rod c which supports on a ball and socket joint, the
supply contact piece d, the sides of which are enclosed in an insulating covering,
and which can slide in a suitably insulated guide in the cover B.
This contact piece is consequently raised up by the said motion of lever a and in
rising the conducting lower part e thereof is made to slide against a spring
contactffixed to an insulator and connected by a cable f¹ with the main circuit.
A contact bar on the underside of the vehicle slides over the contact d as above
described.

page_text: A second rod g, resting on the long arm of lever a is made by the upward motion
of the latter, to project up through a slot in the top of the box, and when the
contact bar of the vehicle passes away from the contact d, a roller carried by the
vehicle passes over and depresses the rod g again, thereby forcibly depressing
the lever and the contact d and consequently disconnecting this from the circuit.
The box A is closed watertight by the cover B which makes a good joint with
the contiguous paving; it is provided with an opening at bottom for drawing off
any water that may possibly penetrate into it. These apparatus are fixed along
the line of rail at short distances apart, determined by the length of the vehicles,
and are fixed in any suitable manner to the rails.
The contact bar of the vehicle is preferably formed so as to embrace the two
sides of the head of the contact piece d, as indicated by the dotted lines in Figure 1,
and it is arranged so as to remain in contact, until it has made contact with the
next following apparatus.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :-
Apparatus for supplying electrical energy to tramcars from underground
conductors, consisting of a two-armed lever a, one arm of which is acted upon by a
vertical rod 6 projecting through an opening in the rail, while the other arm
supports an insulated supply contact piece d, the lower end of which, when raised,
makes contact by means of a contact spring with the supply circuit, while the
upper end makes contact with a bar on the vehicle, another rod bearing upon
the long arm of the lever a, being raised above the surface of the road on the
depression of the rod b, in order that by the subsequent passage of a roller on the
vehicle the rod g, lever a and contact shall be depressed so
the connection with the main circuit again, substantially as described.
Dated this 26th day of May 1896.
as to break
ABEL & IMRAY,
Agents for the Applicants.