Improvements in and relating to the Overhead System of Electric Tramways.
Year: 1894

page_text: Date of Application, 28th Feb.. 1894-Accepted, 12th May, 1894
COMPLETE SPECIFICATION.
Improvements in and relating to the Overhead System of Electric
Tramways.
I, ALFRED DICKINSON, of Tramway Depôt, Darlaston, in the County of
Stafford, Engineer, do hereby declare the nature of my said invention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
My invention has for its object Improvements in and relating to the Overhead
System of Electric Tramways & refers more particularly to the trolleys and trolley
poles by which I am enabled to work this system which obviates the necessity of
span or pull over wires with much more ease and certainty.
In order that my invention may be clearly understood and more easily carried
into practise I have appended hereunto three sheets of drawings upon which I have
fully illustrated the nature of my said improvements.
Figure 1., is a diagram plan showing a curve and junction so arranged as to
obviate the necessity of span or pull over wires.
Figure 2., is an elevation of side pole, trolley pole, and trolley in action.
Figure 3., is a section through the head and base of the standard and foot of the
trolley pole.
Figure 4., is a plan of the base of the standard showing torsion springs.
Figure 5., is a section of Figure 4.
Figure 6., is a front elevation of the trolley.
Figure 7., is a side elevation of the trolley.
Figure 8., is a section through same.
Figure 9., is an elevation of the wire clip and insulator.
Figure 10., is a cross section of same.
Figure 11., is a plan of a pull-over arrangement for sharp curves.
Figure 12., is an elevation of the same.
I will proceed to describe the general system to which my improvements apply
and which has for its object an overhead trolley wire without the objection of
the wires spanning the streets which are by the old system required for the
support of the trolley wire or the numerous pull-over wires required in the case
of curves or switches. This difficulty is obviated by running the trolley wire W
along one side of the street suspended from the poles B the trolley being so.
mounted upon a pole that it will readily follow the line of the trolley wire even
when run at a more or less sharp angle and it is with a view to the accomplish-
ment of this that my present improvements are intended as the great desideratum
is for the trolley to run smoothly and truly on its wire and thus obtain constant
and regular contact. Also in the case of the trolley being thrown off provision
is made to prevent any part of it becoming entangled with the clips or supports
in any way.
To obviate this latter the trolley casing A is formed with the
rounded sides a¹ which leave a projection or part which can in any way
become engaged with any part of the supporting arrangement and on one side
within the casing A I form the oil receptacle a² which is connected with the
bearing a³ of the trolley, so that complete lubrication will take place. This
trolley is provided with the stem a¹ which revolves in the head d' of the trolley
pole D the head of the pole being provided with the curved guard d² and
rounded nose d³ which prevents the hooking or catching of the top of the pole
in case of the trolley jumping off the wire. The trolley pole D is mounted upon
the head e¹ of the inner tube or pole E of the standard F and is controlled in
its movement by the torsion springs H, Figures 4 and 5, the ends h¹ of which are

page_text: fixed to the inner tube or standard E the other ends 2 being attached to the
cart T the standard being supported by the base plate J having arm j¹. The top
part of the trolley pole D is insulated at d³ from the saddle part of the pole and
the standard, the wire N being coated with a nonconducting substance from this
part downwards. The tension springs K retain the trolley upon the wire and the
wire W is carried by the poles B and brackets 61 through the clip L and
insulator which hang upon the pivot 2 so as to accommodate itself to the move-
ment of the wire when the trolley is travelling along same. In the case of sharp
curves where the angle of the wire requires to be acute I provide the curved
clip M which projects below the wire at m¹ by which means the trolley travels
easily round the curve and on to the angle and this arrangement applies equally
whether the clip M is supported from a bracket or pulled over by a wire.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. The improvements in and relating to the overhead system of electric
tramways, consisting of the particular arrangement and construction of the
standards F and E and trolley pole D substantially as and for the purpose herein
set forth and shown upon the accompanying drawings.
2nd. In improvements in and relating to the overhead system of electric tram-
ways the trolley A substantially as and for the purpose herein set forth and shown
upon the accompanying drawings.
3rd. In improvements in the overhead system of electric tramways the supporting
clip L or M substantially as and for the purpose herein set forth and shown upon
the accompanying sheets of drawings.
Dated the 23rd day of February 1894.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent for Applicant.