Improvements in or relating to Electric Railways and Tramways on a Road Contact System.
Year: 1899

page_text: Date of Application, 19th June, 1899-Accepted, 11th Nov., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to Electric Railways and Tramways on a
Road Contact System.
We, EMANUEL CERVENKA and SIMON MAHLER, Merchants, of Prague, in the
Empire of Austria, 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 present invention relates to electric traction on the underground or con-
duit system, in which the contact is produced by means of contact bolts which are
raised when required to effect contact with the car or vehicle.
The invention is illustrated in the accompanying drawings in which,
Figure 2 represents a cross section of the track,
Figure 3 a longitudinal section,
Figure 4 a plan view, and
Figure 1 a detail view.
The current is supplied from a cable well insulated and placed under the sur-
face of the road, the return current passing through the rail, or through the earth.
The contact between the cable and the motor on the car or vehicle is produced by
means of contact bolts which are actuated by a special operating device, the con-
tact apparatus (contact bolts and their respective actuating devices) forming the
main object of the present invention.
The operating device for the contact bolts comprises a casing G sunk into the
ground below or adjacent to one of the rails, which casing G is provided with a
vertical shaft w (Figure 2) provided at its upper end with a toothed' wheel a
(having in the construction to be described four teeth), and at its lower end with a
bevel wheel R both fast on it, the latter gearing with a bevel wheel r keyed on a
horizontal shaft W. The diameters of the wheels R and r are to each other in
the ratio of two to one, e. r makes two revolutions whilst R is making one revo-
lution. Moreover, the operating wheel a (see Figure 1) is so arranged that always
one of its teeth projects into the groove of the track S, thus obstructing it...
In line with the casing G and preferably in the centre of the track (between
the rails) is another casing G₁, also sunk to the level of the road, which casing
contains the contact bolt mechanism.
The shaft W passing through the tube m (connecting the two casings G and
G) is provided at its other end with a crank K and connecting rod p by the move-
ment of which the bolt B.connected with it is moved up and down; whenever,.
for instance, the wheel R is moved by means of the operating wheel a through an
angle of 90° the wheel r will rotate through an angle of 180°, and by means of
the crank mechanism (K, p) the bolt B will be moved upwards, or downwards as
the case may be.
The construction of the contact device is as follows:-
The cover c of the casing G¹ forms a kind of guide P, in which the contact
bolt B is movable in a straight line. In the lower part of the casing G¹ is arranged
a contact plate or part o well insulated by some insulating substance i, which
insulated contact plate o is in good electrical connection by a cable or the like d,

page_text: with the main cable. A contact roller y presses against the contact plate o, the
roller y being carried on a spindle movable in a tube u. The contact roller is
pressed steadily against the contact plate o by means of a spiral spring s.
The contact bolt B consists of two telescopic small tubes t and I, between
which is arranged an insulating tube of which tubes the outer one t fits into
the guide tube P, and is easily movable in it, while the inner tube is metalli-
cally and electrically connected with the spindle v. Within the tube is the
movable bolt which is so constructed as to be capable of an upward movement to
a limited extent. The bolt is pressed upwards by a spring F and is provided on
the top with a strong contact knob or plate z. The distance of the contact bolts
must not be greater than the length of the shortest car used on the track.
The vehicle is provided on its under side and at a height of say between 10°
and 15 centimetres from the roadway with a longitudinal contact plate e, say
about 50 centimetres wide, connected with the car by means of the insulating
rods J, the plate being about 20 to 30 centimetres longer than the distance between
two contact bolts. At its ends the plate is slightly bent upwards. The contact
plate is electrically connected with one pole of the motor on the car while the
other pole of the motor is connected to the frame and wheels, the current thus
passing through the latter to make the return circuit.
The carriage is also provided with two depending arms H, H', the distance
between them being about 2 to 3 centimetres greater than the distance between
two contact bolts. Both arms H, H' are arranged in line on the side of the car
which passes over the operating device.
The arms may be rounded off at their lower ends and are formed and placed
so that their lower ends enter into the groove of the rail which is provided with
the operating wheel (Figures 3 and 4). The operation is as follows, considering
for instance the position of the car to be as represented in the drawings.
The arm H has just turned the operating wheel a of the apparatus III through
an angle of 90° and consequently, by means of the crank K. moved the contact
bolt to its highest position.
is pressed against
In consequence of this upward movement the contact roller
the contact plate o and the contact button is pressed against the contact plate E,
the current thus passing from the cable through the branch d, contact plate o, the
roller Y: the pin v, tube bolt b contact button z, plate E to the motor and from
thence through the conductors did to the rails, on which it returns to the source
of electricity.
The motor is thus driven, the car starts and moves on until the arm H¹ arrives
at the contact device III, turning the wheel a to a further extent of 90°, and
thereby lowering the contact bolt to its lowest position, whereby the contact
roller y is moved down out of contact with the plate o, and the circuit is inter-
rupted. At the same time the arm H had come in contact with the operating
wheel a of the next device IV, and turned it through an angle of 90°, bringing
thereby its contact bolt to the highest position and producing contact with the
contact plate E, whereupon the motor is fed with current through the device IV,
and so on.
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:-
1. An electric traction system in which the electric current is communicated
from an underground cable to the motor on the vehicle by means of a series of
contact bolts which are raised and lowered to make and break contact, as the car
travels, with a contact plate arranged on the vehicle and electrically connected
to the motor.
2. In an electric traction system of the kind described, a series of casings at
equal distances apart and sunk to the level of the roadway, each containing a

page_text: contact bolt adapted to be moved up and down, by suitable means, such as a
crank and gearing, a contact roller and a plate such as o for transmitting the
current from the main cable to the bolt and thence to the motor when the bolt
is raised, the circuit being broken when the bolt is lowered, substantially as
described.
3. An operating device for raising and lowering the contact bolts arranged at
the side of each contact bolt along the line, each consisting of a tooth wheel sup-
ported in a casing sunk into and up to the level of the track, one tooth of which
projects into the rail groove, said wheel being keyed on a vertical axis connected
to the contact bolt mechanism in such manner that when the tooth projecting
into the rail groove is struck by an arm depending from the car the shaft will
be turned and will operate to move the contact bolt, substantially as described.
4. The complete contact device and operating device therefor substantially as
described or illustrated in Figures 1 and 2 of the accompanying drawings.
5. The complete electric traction system substantially as described.
Dated this 19th day of June 1899.
BOULT & WADE,
Agents for the Applicants.