GWR Route: Banbury to Wolverhampton
Handsworth & Smethwick: gwrhs1988
One of the Great Western Railway Train Describer
instruments from Handsworth and Smethwick Signal Box. On busy or complex routes
it was useful for a signalman to know the destination of each approaching train
and this lead to the development of the train describer instrument (also called
route indicators). This particular train describer instrument was manufactured
by Tyler & Company, who had patented the design in December 1879 (Patent No
2575).
The top dial received indications from a similar instrument
in the adjacent Queens Head Signal Box about the destination of the train
approaching on the down relief line, while the lower instrument was used by the
signalman at Handsworth and Smethwick Signal Box to transmit indications to the
signalman at Queens Head Signal Box about the destination of the train leaving
his section on the up relief line.
The instrument worked by the placing of a metal peg into
the appropriate hole and then pulling out the plunger on the right hand side.
This plunger was spring loaded which provided the mechanical power to drive a
small armature within the case. The armature rotated clockwise passing a series
of contacts until it was stopped by the pin. As it passed each contact an
electrical pulse was transmitted to the remote end where each pulse incremented
the pointer on the dial of the receiving instrument.
The Great Western Railway magazine of November 1910 carried
the following article: Train Describers: Tyseley and
Handsworth
Consequent upon the extensive alterations now in progress
in the vicinity of Birmingham and the reconstruction of the Birmingham Snow
Hill Station, it has been determined to equip the Up and Down main and Up and
Down relief lines between Tyseley Junction and Handsworth Junction with train
describers. The Up and Down avoiding lines between Birmingham North and South
Boxes will, in addition to the Up and Down main and Up and Down platform lines,
be similarly equipped. The work will involve the provision of sixty sets of
apparatus, each consisting of a transmitter and receiver, the number of
indications varying from six to ten, due regard being paid to spares in view of
future development. The instruments will be constructed on what is known as the
step by step principle, a single-line wire sufficing for each set
of apparatus. The object of the train describer is of course, to give instant
information of the destination of approaching trains to signalmen to enable
them to promptly dispose of the trains in their proper order. Doubtless the
introduction of the system will be much appreciated by those responsible for
the conduct of the traffic on the section in question.
Robert Ferris
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