Improvements in and relating to Conduits for Electrical Traction.
Year: 1896

page_text: Date of Application, 18th Dec., 1896
10th Coat 4007 Accented 6th Nov 1907
PROVISIONAL SPECIFICATION.
Improvements in and relating to Conduits for Electrical Traction.
I, JOHN EDWARD WALLER, of 29, Great George Street, Westminster, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to underground conduits and their accessories, used for the
reception of a cable or cables in electrical traction, and has for its object the
specific construction and arrangement of parts to give the fullest available space in
the said conduit under the rails, with at the same time an exceptionally shallow
depth to the roof of the said conduit and supporting yokes.
It has been found in certain circumstances, that it is impossible to carry
under-ground conduits through the public streets to any great depth, and that in
consequence special arrangements and combination of parts have had to be devised
to meet such conditions, and these are the subject matter of my present
invention.
The bearing rail, carrying the rolling load is bedded vertically over and upon one
side of the conduit whilst the guard rail, lying over the crown of the said conduit is
bedded only under the crown and at the side of said rail, upon the other projecting
end of the yoke piece, thus giving a clear head-way to the conduit under the yoke
right up to the base of the said guard rail.
To keep the yoke as shallow as possible also, under the open space of the conduit,
I employ yokes of special type for the purpose. I form the side plates as separate
castings with base plates extending widely outwards from the conduit, and I connect
these side plates, into a solid yoke, by a flat plate preferably of wrought iron or
steel for thinness of section, to which I bolt or rivet the said side plates. The
thickness of this base plate is the only depth below that of the open space of the
conduit to which I need go to admit the yokes.
To complete the roofing or covering of the said conduit it is necessary as a
consequence of the before-described construction to maintain the clear head-way
in the conduit, that the roofing plate between yokes should bed against the side of
the said guard rail. This I effect by making the covers of an L or form bedding
the horizontal limit upon the concrete wall of conduit and the vertical limit as a
flange against the web of the guard rail. This arrangement gives great advantages
in that the roofing plates so made and attached can be fixed after the rails
are in place at any time in the course of construction and can afterwards be
removed with ease for access to the conduit, without disturbance of the rails or
yokes.
Much difficulty also arises in providing sufficient strength within the limits of the
depth of the rail without encroachment upon the open space of conduit in the
switch tongue and beel casting, where two roads meet, such switch tongue
and heel casting, carrying the weight of the rolling load, and being at
the same time the roof of a double diverting conduit. This difficulty I have
overcome by bringing forward the point of support of the heel casting to about the
centre of the switch tongue, thus converting the switch from a long cantilever into
a lever of the first kind, converting the downward pressure of the load upon the

page_text: point of the switch into an upward thrust at the heel of the switch tongue, taken
there by a suitable upper member of the heel casting. The requisite depth to give
necessary stiffness to the switch tongue is thus reduced by reduction of unsupported
span. The heel plate supporting the switch tongue is stiffened with two diverging
ribs from toe to heel, and the other heel of the switch lies between the said ribs.
The switch tongue has a central vertical rib for stiffness strengthened by a lateral
flange at its lower edge. This flange can pass under the outer ends of the rib of
the heel plate where the said ribs are close together near the outer end of the
cantilever heel plate, and as they diverge towards the heel, the said ribs can be
deepened downward without fouling the lower flange of the switch lying between
them. I thus obtain in this switch and heel-plate sufficient transverse strength as
cantilevers to carry their proportions of the rolling load, within the very shallow
limits of vertical depth represented by the depth of the rail, so as to leave the
conduit space clear right up to the under head or flange of the guard rail.
Dated this 18th day of December 1896.
FELL & JAMES,
1 Queen Victoria Street, London, E.C., Agents for the Applicant.
Improvements in and relating to Conduits for Electrical Traction.
J JOHN EDWARD WALLER of 29 Great George Street Westminster, Civil Engineer
do hereby declare the nature of this Invention and in what manner the saine is
to be performed to be particularly described and ascertained in and by the following
statement:-
My invention relates to underground conduits, and their accessories, used for the
reception of a cable or cables in electrical traction, and has for its object the specific
construction, and arrangement of parts to give the fullest available space in the said
conduit under the rails, with at the same time an exceptionally shallow depth to the
roof of the said conduit and supporting yokes.
It has been found in certain circumstances, that it is impossible to carry under
ground conduits through the public streets to any great depth, and that in consequence
special arrangements and combination of parts have had to be devised to meet such
conditions, and these are the subject matter of my present invention.
And in order that my invention may he the better understood I now proceed to
describe the same, reference being had to the drawings hereto annexed, and to the
letters and figures marked thereon.
Fig. 1. Is an end view of a conduit yoke.
Fig. 2. Is an end view of a shallowest yoke and metal man-hole cover.
Fig. 3. Is a plan of a movable switch tongue and heel plate.
Fig. 4. Is a vertical section of the same.
The bearing rail A carrying the rolling load is bedded vertically over and upon one
side of the conduit yokes B, whilst the guard rail C lying over the crown of the said
conduit, is bedded only under the crown and at the side of said rail, upon the other
projecting en B¹ of the yoke piece, thus giving a clear headway to the conduit under
the yoke, right up to the base of the said guard rail.
Where it is desirable to keep the yoke as shallow as possible also, under the open
space of the conduit, I employ yokes of special type for the purpose as in Fig. 2. I
form the side pedestals B B as separate castings, with base plates D D extending
widely outwards from the conduit, and I connect those side pedestals B B¹, into a
solid yoke, by a flat blade E preferably of wrought iron or steel for thinness of

page_text: section, to which I bolt or rivet the said side pelestals. The thickness of this base
plate is the only depth below that of the open space of the conduit to which I need
go to admit the yokes.
To complete the roofing or covering of the said conduit it is necessary, as a
consequence of the before described construction, to maintain the clear headway in
the conduit, that the roofing plates between yokes should bed against the side of the
said guard rail.
This I effect by making the covers of an L or form F bedding the horizontal
limb upon the concrete wall of the conduit and the vertical limb as a flange against
the web of the guard rail C to which it is secured by suitable fastenings. This
arrangement gives great advantages, in that the roofing plates so made, and
attached, can be fixed after the rails are in place at any time in the course of
construction, and can afterwards be removed with ease for access to the conduit,
without disturbance of the rail or yokes.
Much difficulty also arises in providing sufficient strength (within the limits of the
depth of the rail without encroachment upon the open space of conduit) in the switch
tongue and heel casting, where two roads meet, such switch tongue and heel casting,
carrying the weight of the rolling load, and being at the same time the roof of a
double dividing conduit.
This difficulty I have overcome as in Figures 3 and 4 by bringing forward the point
of support of the heel casting C to about the centre of the switch tongue H, thus
converting the switch from a long cantilever into a lever of the first kind, and
converting the downward pressure of the load upon the point of the switch H into an
upward thrust at the heel H1 of the switch tongue, taken there by a suitable upper
member of the heel casting G. The requisite depth to give necessary stiffness to
the switch tongue is thus reduced by reduction of unsupported span. The heel plate
supporting the switch tongue is stiffened with two diverging ribs K K' from toe to
heel, and the heel of the switch lies between the said ribs. The switch tongue has
a central vertical rib for stiffness strengthened by a lateral flange 1. at its lower edge.
This flange can pass under the outer ends of the rib K of the heel plate, where the
said ribs are close together near the outer end of the cantilever heel plate, and as they
diverge towards the heel, the said ribs can be deepened downwards without fouling
the lower flange L of the switch lying between them.
I thus obtain in this switch and heel-plate sufficient transverse strength as cantilevers
to carry their proportion of the rolling load, within the very shallow limits of vertical
depth, represented by the depth of the rail, so as to leave the conduit space clear
right up to the under head or flange of the guard rail.
The switch tongue H pivotting on its central support M is operated by a steel
spring bar N, engaging in the heel H of the switch tongue, the spring bar N being
deflected by a crank or eccentric cam P pivotted in the heel-plate support casting Q,
and working in a stirrup or bridle R at the rear end of the said spring bar N.
Having now particularly described and ascertained the nature of this said inven-
tion and in what manner the same is to be performed, I declare that what
I claim is
1st. In a conduit, adapted for electrical traction, the arrangement of the carrying
and guard rails, relatively to the bearing yoke of the said conduit to give maximumn
bead within the conduit under the said rails, substantially as described.
2nd. In a conduit adapted for electrical traction, the combination with side pedestals
of a flat connecting bottom plate, giving smallest external depth of yoke with
maximum internal capacity for cable and fittings, substantially as described.
3rd. In a conduit adapted for electrical traction, the combination with such conduit
of a reverse flanged covering plate, adapted to bed at one end upon chest of guard
rail and at the other upon the conduit wail, substantially as described.
4th. In a conduit adapted for electrical traction, the combination of a moving
switch tongue, with a heel plate, supporting such switch tongue at or about its centre

page_text: and having a counter stop piece above the heel of said switch tongue to take its
upward thrust substantially as and for the purposes described.
Dated this 16th day of September 1897.
FELL & JAMES,
1 Queen Victoria Street, London, E.C., Agents for the Applicant.