Improvements in Contact Boxes for Electric Tramways and the like.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Contact Boxes for Electric Tramways and the like.
I, CLAUDE KENNEDY MILLS, of 23, Southampton Buildings, in the County of
London, Patent Agent, do hereby declare the nature of this invention (a com-
munication to me from Edouard Bonnet, Engineer, of 21, Place Bellecour. Lyons,
Jules Paufique, Contractor, of 15, Rue Saint Dominique, Lyons and Georges
Liniere Mechanical Engineer, of Ecully (Rhône) all in the Republic of France)
to be as follows:-
The invention relates to the permanent ways of electric tramways and rail-
ways in which the vehicles obtain the current by means of contact plugs arranged
a short distance apart at the surface of the roadway and placed successively in
communication, by the passage of the vehicle, with an underground conductor.
It is particularly applicable in those cases where the communication. of the
conductor with the exterior plugs takes place by means of an iron contact piece
attracted by an energized or magnetized bar placed under the vehicle.
In the applications which have been made of this system it has been noticed
that the operation of the interrupted parts was often troubled by the humidity
of the atmosphere or of the ground, the condensation of which may produce
derived currents between the contact piece and the plug and even form between
these two parts a film of water or ice establishing a dangerous permanent com-
munication.
It is further very difficult to place in position and to regulate the various parts
of the apparatus.
The invention has for its object to shelter these organs from humidity and to
assemble and regulate them before placing them in position, to render them
easily transportable, and capable of being placed in position without special
precautions.
The invention is illustrated in the accompanying drawings in which Fig. 1
shows in section one arrangement of apparatus and Fig. 2 shows a slight, modifi-
cation thereof.
M is one of the cavities which are arranged a short distance apart upon the
permanent way to receive the contacts it is closed by a cover N level with the
ground at its edges and carrying at its centre the iron plug G under. which is
screwed the interior contact C. The movable contact is an iron rod A, situated
in a mercury cup or container H in constant communication with the line current.
When the magnetized or energized bar fixed under the vehicle comes into con-
tact with the plug G. this latter attracts the movable contact A and the current
passes to the vehicle through the magnetized or energized bar.
The parts which should be particularly preserved from damp are: the movable
contact piece A attracted by the magnetized or energized bar of the vehicle, and
the fad aoutant firend to the cover of the box

page_text: In the arrangement shown in Fig. 1 these two parts are enclosed in an air
tight box, formed of two parts B and D connected by an india rubber or other
point E by means of bolts or in other convenient manner.
The upper part B is held between the plug G and the fixed contact C or these
two pieces B and C are soldered together; the lower part D is screwed upon the
mercury cup or container H into which plunges the movable contact A. The
cup or container H being made of ebonite or other non-conducting material,
insulates this contact from the box B D which may be made of metal.
It is also very important to place that part of the conducting cable from which
the current is taken sheltered from the water which may accumulate in the
cavity M in which the box is placed.
The current is taken off by a rod I, screwed to the bottom of the mercury cup
or container H and dipping in a mercury cup J carried by the end of the con-
ducting cable K. This part is prevented from coming into contact with water
which might get into the cavity M, by an ebonite bell L which descends a little
lower than the metal cup J.
By this construction the entire apparatus is suspended from the cover N of
the box and may be lifted with it for inspection and repairs.
The electric contact between the movable contact A and the rod I may be
made by other means for example by a flexible cable or a spiral wire, it is pre-
ferred to employ mercury, but in this case it is difficult to prevent a certain
amount of oxidation of the mercury, from which it results that the movable
piece A becomes covered upon the surface which dips in the mercury with a
powder which interferes with the passage of the current.
This inconvenience is overcome by screwing to the lower part of the contact
piece an end piece made of copper which becomes amalgamated and assures an
excellent contact.
It is neither indispensable to employ mercury for taking off the current. It
can be accomplished by any form of contact which disengages itself.
In order to prevent any welding between the surfaces of the two contacts by
the passage of the current, these latter are provided with carbon fittings Q
and S.
Fig. 2 shows a slight modification from the apparatus herein before described
in which the fixed joint E is replaced by a hydraulic joint: the box B in the
form of a bell dipping into the liquid contained in a circular channel D
around the mercury cup or container H. This arrangement enables the cover N
to he dismounted without displacing the other parts of the apparatus, but it
necessitates a special apparatus to prevent the differences of pressure between
the interior and the exterior of the box B, D, allowing damp air to penetrate into
this latter.
The arrangement invented for this purpose consists in causing the box to
communicate with a closed chamber P formed of a flexible membrane which can
receive and return a portion of the air of this box, according to the variations
of temperature which tend to augment or diminish the pressure in the interior
of the said box, without the level of the liquid making the joint varying
sensibly.
The chamber P may have any desirable form preferably that shown in Fig. 2,
namely a circular india rubber tube.
As in the arrangement previously described, that part at which the current
is taken in the lower portion of the box is protected by a bell L made of insu-
lating material.
Datod this lot dar of Tune 1000
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.

page_text: Improvements in Contact Boxes for Electric Tramways and the like..
I, CLAUDE KENNEDY MILLS, of 23, Southampton Buildings, in the County of
London, Patent Agent, do hereby declare the nature of this invention (a com-
munication to me from Edouard Bonnet, Engineer, of 21, Place Bellecour, Lyons,
Jules Paufique, Contractor, of 15, Rue Saint, Dominique, Lyons and Georges
Liniere, Mechanical Engineer, of Ecully (Rhone). aii in the Republic of France)
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
-:
The invention relates to the permanent ways of electric tramways and rail-
ways in which the vehicles obtain the current by means of contact plugs arranged
a short distance apart at the surface of the roadway and placed successively by
the passage of the vehicle in communication with an underground conductor.
It is particularly applicable in those cases where the communication of the con-
ductor with the exterior plugs takes place by means of an iron contact piece
attracted by an energized or magnetized bar placed under the vehicle.
In the applications which have been made of this system it has been noticed
that the operation of the interrupted parts was often troubled by the humidity of
the atmosphere or of the ground, the condensation of which may produce derived
currents between the contact piece and the plug and even form between these
two parts a film of water or ice establishing permanent communication- dangerous
for passers by.
It is further very difficult to place in position and to regulate the various
parts of the apparatus.
The invention has for its object to shelter these organs from humidity and to
assemble and regulate them before placing them in position, to render them easily
transportable, and capable of being placed in position without special precautions.
The invention is illustrated in the drawings accompanying my Provisional
Specification in which Fig. 1 shows in section one arrangement of apparatus
and Fig. 2 shows a slight modification thereof.
M is one of the cavities which are arranged a short distance apart upon the
permanent way to receive the contacts, it is closed by a cover N level with the
ground at its edges and carrying at its centre the iron plug G under which is
screwed the interior fixed contact C. The movable contact is an iron rod A,
situated in a mercury cup or container H in constant communication with the
line current.
When the magnetized or energized bar, fixed under the vehicle comes into
contact with the plug. G. this latter attracts the movable contact A and the current
passes to the vehicle through the magnetized or energized bar.
The parts which should be particularly preserved from damp are: The movable
contact piece A attracted by the magnetized or energized bar of the vehicle, and
the fixed contact C fixed to the cover of the box.
In the arrangement shown in Fig. 1 these two parts are enclosed in a hermetic
box, formed of two parts B and D), connected by a joint of india rubber or other
material E by means of bolts or in other convenient manner.
The upper part B is held between the plug G and the fixed contact C or these
two pieces B and C are soldered together: the lower part D is screwed upon the
mercury cup or container H into which plunges the movable contact A. The
cup or container H being made of ebonite or other non-conducting material,
insulates this contact from the box B, D, which may be made of metal.
It is also very important to place that part of the conducting cable from which

page_text: the current is taken sheltered from the water which may accumulate in the
cavity M in which the box is placed.
The current is taken off by a rod I, screwed to the bottom of the mercury cup
or container H and dipping in a mercury cup J carried by the end of the con-
ducting cable K. This part is prevented from coming into contact with water
which might get into the cavity M. by an ebonite bell L which descends. a little
lower than the metal cup J, the air imprisoned in this bell is sufficient to prevent
the water from coming into contact with the cup J.
By this construction the entire apparatus is suspended from the cover N of
the box and may be lifted with it for inspection and repairs.
The electric contact between the movable contact A and the rod I may be made
by other means for example by a flexible cable or a spiral wire, it is preferred to
employ mercury, but in this case it is difficult to prevent a certain amount of
oxidation of the mercury, from which it results that the movable piece A. becomes
covered upon the surface which dips in the mercury with a powder which in-
terferes with the passage of the current. This inconvenience is overcome by
screwing to the lower part of the contact piece an end piece made of copper which
becomes amalgamated and assures an excellent contact.
It is neither indispensable to employ mercury for taking off the current. It
can be accomplished by any form of contact which disengages itself.
In order to prevent any welding between the surfaces of the two contacts by
the passage of the current, these latter are provided with carbon fittings Q and S.
Fig. 2 shows a slight modification from the apparatus hereinbefore described
in which the fixed joint E is replaced by a hydraulic joint; the box B in the
form of a bell dipping into the liquid contained in a circular channel D around
the mercury cup or container H. This arrangement enables the cover N to he
dismounted without displacing the other parts of the apparatus, but it necessi-
tates a special apparatus to prevent the differences of pressure between the interior
and the exterior of the box B, D allowing damp air to penetrate into this latter.
The arrangement invented for this purpose consists in causing the box to
communicate with a closed chamber P formed of a flexible membrane which can
receive and return a portion of the air of this box, according to the variations of
temperature which tend to augment or diminish the pressure in the interior of
the said box, without the level of the liquid making the joint varving sensibly.
The chamber P may have any desirable form preferably that shown in Fig. 2,
namely an annular india rubber tube.
As in the arrangement previously described, that part at which the current
is taken in the lower portion of the box is protected by a bell L made of
insulating material.
Having now particularly described and ascertained the nature of the said in-
vention and in what manner the same is to be performed I declare that what I
claim is:
1. In a contact box for electric tramways and the like in which the current
is taken from plugs level with the surface of the road. by means of a magnetized
bar, the combination with the fixed contact C and movable contact A of a metallic
rod I in electric contact with the movable contact A and connected to the end of
the conducting cable, so as to transmit the current from the cable to the contact A
without a rigid connection, substantially as herein shown and described.
2. In a contact box for electric tramways and the like in which the current is
taken from plugs level with the surface of the road by means of a magnetized
bar the combination of a hermetic box, enclosing and protecting the contact
pieces C and A, with a bell arranged at the lower part of said hermetic box for
protecting that part of the cable from which the current is taken, substantially as
herein shown and described.
3. In a contact box for electric tramways and the like in which the current is
taken from plugs level with the surface of the road by means of a magnetized
1

page_text: bar, the combination of a hernietic box with an air tight clastic chamber P
communicating with the box and maintaining an equilibrium between the in-
terior and the exterior pressure, substantially as herein set forth.
4. In a contact box for electric tramways. and the like, the combination of
a fixed plug and contact piece, a movable contact piece arranged in a hermetic
box and dipping into a mercury cup, a rod in communication with said mercury
cup and dipping into a mercury cup carried by the conducting cable and a pro-
tecting bell carried by the hermetic box, substantially as set forth.
Dated this 27th day of February 1900.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.