Improvements in Detector Bars for Railway Points and Signals.
Year: 1892

page_text: Date of Application, 6th Sept., 1892
Complete Specification Left, 4th July, 1593-Accepted, 2nd Sept., 1893
PROVISIONAL SPECIFICATION.
Improvements in Detector Bars for Railway Points and Signals.
I, LEICESTER BRADNEY STEVENS, of Darlington Works, Southwark Bridge
Road, in the County of Surrey, Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention for improvements in detector bars for railway points and signals
has for its object to prevent collisions on railways at crossings and junctions, and
consists in the employment of very long detector bars on either side of the said
crossing arranged in such manner that they can be easily counterweighted so as
to render their manipulation from the signal box easy either, by a separate.lever
or by the lever that operates the points.
When using the ordinary lifting bar I arrange the oscillating rockers so that
they do not turn beyond a vertical position when the bar is elevated to its highest
position.
When fixed on the main line near a crossing the bar is elevated if the points
are set for anything to cross the main line and normally down when the points
are set for main line traffic.
These bars being counterweighted are applicable for junctions, to work with the
points and so dispense with the ordinary clearance bars and levers usually employed
for working the same.
Dated this 6th day of September 1892.
WHEATLEY & MACKENZIE,
40, Chancery Lane, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Detector Bars for Railway Points and Signals.
1 LEICESTER BRADNEY STEVENS, of Darlington Works, Southwark Bridge
Road, in the County of Surrey, Engineer, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
This invention for improvements in detector bars for railway points and signals
has for its object to prevent collisions on railways at crossings and junctions, and
consists in the employment of very long detector bars on either side of the said
crossing arranged in such manner that they can be easily counterweighted so as to
render their manipulation from the signal box easy either by a separate lever or by
the lever that operates the points.
Referring to Figures 1 and 2 of the accompanying sheet of illustrative drawings
Figure 1 is a diagramatic plan showing three lines of rails and a crossing fitted
with detector bars constructed according to this invention.
Figure 2 is a perspective view showing in detail means for supporting and
counterbalancing a detector bar.
b
On the line a over which the crossing passes are arranged on either side of the
said crossing long detector bars c mounted on parallel oscillating rockers d which
support thein and permit of a limited motion in a vertical plane.
One rocker is mounted on a shaft e connected by a lever fand rod connection g
to the point rods and to the point lever in the signal box h in the ordinary manner.
The rockers d are inclined to the vertical on one side of it in all positions of the
bar c and on the shaft e is mounted a weighted lever i by means of which the bar is
counterbalanced as will be readily understood.

page_text: When fixed on the main line near a crossing as shown the bar is elevated if the
points are set for anything to cross the main line and normally down when the
points are set for main line traffic.
These bars being counterweighted are applicable for junctions to work with the
points and so dispense with the ordinary clearance bars and levers usually employed
for working the same.
Instead of the counterbalanced detector bars having a motion in a vertical plane
as hereinbefore described they may be arranged to work horizontally as shown in
transverse section in Figure 3 the counterbalancing being thereby dispensed with.
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 :-
1. The employment of detector bars arranged on either side of a crossing acting
simultaneously and operated in conjunction with the points of the crossing or by a
separate lever substantially as described.
2. In railway point and signal apparatus the construction of a detector bar
mounted ou inclined rockers and counterbalanced substantially as described and for
the purpose set forth.
3. The arrangement and construction of detector bars for railway points and
signals substantially as described with reference to Figures 1 and 2 of the
drawings.
Dated this 4th day of July 1893.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.