Improvements in Supports for the Current Collectors of Electric Railways and Tramways with Overhead Conductors.
Year: 1897

page_text: Date of Application, 12th Aug., 1897
Complete Specification Left, 30th Apr., 1898-Accepted, 4th June, 1898
Improvements in Supports for the Current Collectors of Electric
Railways and Tramways with Overhead Conductors.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate, Westminster,
S.W., Electrical Engineers, do hereby declare the nature of this invention (as com-
municated to us by Messrs. Siemens & Halske, of Markgrafen Strasse 94, Berlin,
S.W., Germany, Electrical Engineers) to be as follows:-
The present invention relates to that kind of current collector used on electric
railways and tramways with overhead conductors in which a rigid arm pivotted to
the top of the car projects up to the underside of the overhead conductor where it
carries a current collecting device which is pressed upward against the conductor.
According to this invention the construction of the support of such collectors is
so arranged that it is caused to automatically reverse its position on the change of
direction of the cars running, the arm and collector being balanced by a counter-
weight.
.
For this purpose a two-armed framed lever is mounted on pivots in brackets
fixed on the top of the car, the long arm of the lever being provided with a
counterweight which tends to keep it in a vertical position.
To the upper short arm of the lever is pivotted the arm which carries the current
collector, the arm being provided with a weighted downward extension beyond the
pivot, which tends to keep the arm and collector in a vertical position. On the
arm with its collector being brought under the overhead conductor, it will be
deflected at an angle, turning on its pivot on the double ended lever which will,
however, still retain its upright position, the collector being kept in contact by the
action of the counterweight on the arm.
When the car has its direction of motion reversed, the collector arm, being held
at its upper end by its frictional contact with the conductor, will gradually turn
first from the inclined position into the vertical position, in which motion it pushes
downward the upper arm of the double ended lever, thus raising the weighted arm;
by the continued motion of the car, the arm is then caused to form a gradually
increasing angle on the opposite side, while at the same time the weighted arm of
the lever in descending eventually brings the lever back to the vertical position.
If necessary, stops may be provided on the brackets carrying the lever for limiting
the extreme angular positions of the latter.
The above described construction affords the advantage of simplicity of con-
struction with great freedom and certainty of action as compared with the
constructions with spring action heretofore employed.
Dated this 12th day of August 1897.
ABEL & IMRAY,
Agents for the Applicants.

page_text: Improvements in Supports for the Current Collectors of Electric
Railways and Tramways with Overhead Conductors.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate, Westminster,
S.W., Electrical Engineers, do hereby declare the nature of this invention (as
communicated to us from abroad by Messrs. Siemens & Halske, of Markgrafen
Strasse 94, Berlin, S. W., Germany, Electrical Engineers) 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 that kind of current collector used on electric
railways and tramways with overhead conductors in which a rigid arm pivotted
to the top of the car projects up to the underside of the overhead conductor
where it carries a current collecting device which is pressed upward against the
conductor.
According to this invention the construction of the support of such collectors is so
arranged that it is caused to automatically reverse its position on the change of
direction of the cars running, the arm and collector being balanced by a counter-
weight.
Fig. 1 of the accompanying drawings is a side view and Fig. 2 a front view of
the improved construction while Figs. 3, 4 and 5 shew diagrammatically three
different positions of the current collector.
A two armed frame lever e is mounted on pivots in brackets g fixod on the top of
the car, the long arm of the lever being provided with a counterweight c which
tends to keep the lever in a vertical position.
To the upper short arm of the lever, the frame arm which carries the current
collector is pivotted on the axis f the arm, being provided with a downward
extension attached to which is the counterweight b.
When the car is brought under the overhead conductor and when it is running
the collector will be pressed upwards against the conductor a by the counter-
weight b. When the car is travelling in the direction of the arrow in Fig. 3 the
relative positions of the counterweighted frame lever e and the counterweighted
frame arm d will be as there shewn.
When the direction of travel is reversed, the friction of the upper end of the
collector d against the conductor a will cause the collector to turn to a vertical
position and the lever e to turn on the pivot g to an oblique position, the relative
positions being then such as are shewn in Fig. 4. The weight 6 and the weight
of the collector d will now tend to draw the collector away from the conductor a,
but this tendency is counter-acted by the weight c, and contact with the conductor
is maintained. A break of contact can be further prevented by stops h
Figs. 1, 2 & 4 fixed on the brackets carrying the frame lever; as shewn in Fig. 4
the angular movement of the lever frame is prevented by the axis f striking these
stops. As the reverse direction of travel is continued the counterweight c draws
the lever e downward into the vertical position again and the relative positions of
the frame lever and collector become such as are shewn in Fig. 5.
In addition to the automatic reversal when the direction of travel of the car is
changed, the above described construction has the advantage, owing to the double
jointed support, that even when the car is travelling rapidly and is jolting, the
contact remains good.
Furthermore, the counterweights exert a constant force while the elasticity of
springs, which have heretofore been almost exclusively used, suffers a change in the
course of time.

page_text: This advantage is particularly felt where a mixed system of current supply is in
use, because when the contact arm remains for a longer time in the depressed
position, when an underground supply or accumulator supply is being used, the
springs deteriorate owing to their remaining in a stretched condition.
Finally the reversal of the current collector is effected without unduly pressing
the overhead conducting lead upwards.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what
we claim is :-
A support for a current collector for electric cars with overhead conductors
wherein the current collector arm counterbalanced by a weight in the direction of
travel of the car is pivotted to the one arm of a two armed lever the other arm of
which carries a counterweight, substantially as and for the purpose described.
Dated this 20th day of Anvil 1808
ABEL & IMRAY,
Agents for the Applicants.