IMPROVEMENTS IN COMBINED INTERLOCKING POINTS AND SIGNAL APPARATUS FOR RAILWAYS
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Niels Henrik Holst at the Office of the
Commissioners of Patents on the 26th June 1876.
NIELS HENRIK HOLST, of Aärhuus, in the Kingdom of Denmark, Director of the
Danish State Railways. "IMPROVEMENTS IN COMBINED INTERLOCKING POINTS AND
SIGNAL APPARATUS FOR RAILWAYS."
This Invention relates to a simple and efficient combined interlocking arrange-
ment for points and signals on railways, whereby the points are readily locked for
either one or the other of the adjoining lines, whilst at the same time the signals
are made to indicate, either by day or by night, whether the points are locked or
not, and for which of the adjoining lines they are closed and locked.
In carrying out this Invention the points may be connected in the usual manner
to the point lever, which lever works in a long guiding slot or opening provided
in two double cross levers which serve to actuate the signal employed for indicating
the condition of the points, and with which the point lever is locked by inserting
a pin or a padlock through it and the signal levers. These cross levers are mounted
on one end of a horizontal spindle which passes through the signal post and carries
at its opposite end a T shaped lever, to the pendant arm of which there is attached
a heavy counterweight. To each of the horizontal arms of the said T shaped
lever there is jointed a rod leading up to a semaphore arm for signalling by day,
such arm being provided with the usual colored glasses for showing by the aid of
a lamp the requisite signals by night.
The action of this apparatus is as follows:-So long as the points remain
unlocked the counterweight will cause the vertical arm of the T lever to hang
perpendicularly, and the horizontal arms to assume their natural horizontal position,
thereby maintaining the semaphore arm also horizontal or showing a red light
indicating "danger.'
"
When one or other of the points has been closed by moving the point lever
over in one direction or the other, as the case may be, it is absolutely necessary,
before the interlocking of the point and signal levers can be effected, that the
signal levers shall also be adjusted so as to set the signal to a position which shall
indicate for which line the points have been set and locked. The locking of the
point lever with the signal lever is effected by merely inserting a pin or padlock
attached by a short chain to the point lever through a hole in the said point
lever and in the cross levers which actuate the signal. When the point is closed
Price 2d77

page_text: and locked, say, for the main line, the semaphore arm will be raised to an upward
angle of about 45°, with the post showing a white light, for example, at night.
When the other point is closed and locked for the siding, the semaphore arm will
be lowered to an angle of 45°, showing a green light, for example, at night, and
when the points and signal are left unlocked the semaphore arm will assume a
position at right angles to the post showing a red light at night, thereby indicating
danger."
The said apparatus is of course equally applicable to points whose levers are
supplied with a moveable weight. Should a train come from a siding whilst the
points are locked for the main line, or vice versa, then the locking pin will break
and the weight will show the "danger" signal.<