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GWR Article
Robert Ferris has transcribed the following
information on the building and development of Moor Street station from
articles which appeared in several editions of the Great Western Magazine.
Traversing Tables, Moor Street Station, Birmingham
Extract from Great Western Magazine Vol. XII. No.7, July
1910
The Company's new terminal station at Moor Street,
Birmingham possesses several interesting features one being that the
station is built over the goods depot (not yet opened); another, that
electrically driven traversers have been provided, in place of the usual
cross-over roads for transferring engines of incoming trains to the outgoing
road. Two traversers have been installed, one on either side of the central
platform A on the diagram (gwrbms1698) the intention being that in
addition to serving the platform, they shall eventually be used for those on
the other sides, when built A1.
Each traverser has upon it three tracks (X, Y, Z) at eleven
foot, two and half inch centres. This ensures a track always being opposite to
the running rails, thus obviating the risk of vehicles or an engine falling
into the traverser pit. Sixty feet long by thirty two feet, ten inches wide,
the traversers are capable of travelling with a load of 170 tons at ten feet
per minute, the motive power being a three-phase motor with wound rotor of 18
B.H.P. running at 710 r.p.m. They are provided with thirty six travelling
wheels, two foot diameter, which run on nine rails (fixed at right angles to
the engine track rails), or four wheels to each rail. The under-carriages,
numbering nine, are composed of two rolled steel joists, and on the top of
these are secured the six rail bearing girders, made up of three channels
riveted together which carry the engine track rails, the latter being supported
at intervals by sleeper plates. Chequered steel plates cover the tops of the
traversers, which project sufficiently under the nosing of the platforms to
prevent anyone falling therefrom getting into the pit, and the edges are
finished off with a skirting of angle iron.
The motor and driving machinery, B, are carried on the
traverser, approximately in the centre, under the chequered steel plates, one
of which forms a door directly over the machinery for inspection purposes, etc.
The motor is coupled direct to a steel worm, which gears into a worm wheel with
cast iron centre and phosphor bronze rim; the worm gear complete being
contained in a cast iron box with an oil well for lubrication. An electric
brake is fitted to the worm shaft and is designed to give equal braking force
in both directions, and to free the shaft from any bending action due to pull
of brake band. The motive power is transmitted from the motor to the steel worm
and thence to the worm wheel, which is keyed to a countershaft extending in
both directions from the centre line of the traverser, the ends of the
countershaft in turn gearing into two cast steel wheels on each driving shaft.
Limit switches are provided to prevent the traversers over-running.
The position at Moor Street is somewhat confined, and it
will be readily gathered that the principal idea in providing traversers was to
avoid the long lengths of rail necessary with the usual cross-over roads.
Beneath the platform, on either side of which the
traversers work, is a recess into which they pocket up to nearly
the middle of the platform column, as shown in diagram. The method of working
is to move the traverser under the platform so that the middle pair of rails,
Y, come into line with the train road. The engine goes on to the traverser, is
then uncoupled and the traverser is run out, so that the line upon which the
engine is standing comes into position with the outgoing road, thus enabling
the engine to get off at once to the other end of the train, or elsewhere, as
may be desired. The handles controlling the traversers, which are worked by the
engine drivers, are placed between the stopblocks, an ingenious arrangement
being that they are locked with the signalling apparatus, which is controlled
from the signal box, an indicator being provided to intimate to the drivers
when the traverser is right or wrong. The arrangement
is such, that the stops which have to be released to allow of the traverser
being operated cannot be worked except when the latter is in the correct
position.
Messrs. S.H. Heywood & Co. of Reddish, near Stockport,
constructed the traversers, and the motors were supplied by the Lancashire
Dynamo & Motor Co., 28 Victoria Street, S.W.
One illustration shows the traverser under
weight test ('gwrbms1699'), and another
a traverser in full view ('gwrbms1697').
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