Improvements in Apparatus for Locking Railway Carriage Doors
Year: 1895

page_text: Date of Application, 7th May, 1895.
.
Complete Specification Left, 27th May, 1895-Accepted, 29th June. 1895
Date of Application, 7th May, 1895
.
Complete Specification Left. 27th May, 1895-Accepted, 29th June. 1895
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Locking Railway Carriage Doors
I, JOHN COок BUCHANAN, of 10 Bridge Wharf, in the. City of Glasgow,
Consulting Engineer, do hereby declare the nature of this invention. to be as
follows:-
This invention has for its object the provision of improved locking devices of a
simple and inexpensive kind whereby the whole of the carriage doors of a railway
train may be simultaneously and automatically locked on leaving a platform and
unlocked on arrival at a platform, the locking devices being out of reach of the
passengers and entirely under control of the guard, driver or other official.
The unproved devices comprise a locking. holt for each door, auxiliary to the
ordinary lock and handle used by passengers, the said bolt being formed on or
attached to a piston fitted in a small cylinder placed at any convenient position
with respect to the door. The several cylinders are coupled to branches on a
main pipe curried the length of the train and connected to the boiler or other
vessel under pressure or vacuum such as the reservoir of the air pressure or
vacuum brake
By preference-a.springs fitted in each cylindor to press on the rear of the piston
and maintain the bolt shot out in the locking position, whilst the unlocking or
retracting of the bolt is effected either by vacuum on the spring side of the piston
or by air pressure applied on the bolt side, the bolt being in the latter case carried
through an air-tight cover on the end of the cylinder.
The locking bolt is formed with a beveled face which by contact with a striking
plate ou the door and yielding of the spring permits of the door being closed at
any time, whilst the other face of the bolta hich engages the catch orifice in the
striking plate prevents the door being opened until the bolts retracted by the
vacuum or pressure acting. on the piston in the cylinder.
In lieu of using a spring to shoot out the holt it may be normally so held by air
pressure acting on differential areas of the nner and outer side of the piston, the
retinetion of the bolt being, effected by relieving the pressure on the rear of the
piston or the unlocking may be effected by applying the air pressure to the greater
area. Or, again the spring may serve to effect the unlocking whilst the air
pressure or vacuum is employed to shoot out the bolt, the arrangement being
susceptible of several variations.
The pipes on the several vehicles are coupled together in a manner well-known
As applied to automatic brakes, and the whole of the locking bolts are actuated
simultaneously by means of a cock in the guard's van or on the locomotive,
In the event of collision severing. the train or breaking the pipe-connections, the
doors automatically unlock.
D. 1... SM 1005

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Locking Railway Carriage Doors.
I, JOHN COOK BUOHANAN, of 10 Bridge Wharf, in the City of Glasgow,
Consulting 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 has for its object the provision of improved locking devices of a
simple and inexpensive kind whereby the whole of the carriage doors of a railway
tram may be simultaneously and automatically locked on leaving a platform and
unlocked on arrival at a platform, the locking devices being out of reach of the
passengers and ontuely under control of the guard, diver on other official
As illustrated by the accompanying diawings, Fig 1 of which is a part longi-
tudinal section, Fig. 2 a part transverse section of a railway carriage and Fig 3 a
modification of the locking bolt and cylinder the improved devices compuse a
locking bolt A for each dooi G auxiliary to the ordinary lock and handle used by
passengers, the said bolt being formed on or attached to a piston B fitted in a small
cylinder placed at any convenient position with respect to the door. The
several cylinders C are coupled to branches D on a main pipe E cared the length
of the train and connected to the boiler or other vessel under pressure of vacuum
such as the reser von of the air pressure or vacuum biake, or by epecial reservoir
and air pump.
The locking of the carriage door G is by preference effected by the action of
the compressed air on the rear of the piston B as at Figs 1 and 2 oi by vacuum on
the inner side of the piston as at Fig 3 which maintains the bolt shot, whilst the
unlocking on retracting of the bolt 13 effected by a spring which acts between the
upper end of the cylinder C and the piston B.
The locking bolt A is formed with a beveled face a which by contact with a
striking plate H on the door G and yielding of the an pressure or of the spring
permits of the door G being closed at any time, whilst the other face of the bolt
which engages the catch orifice I in the striking plate II prevents the door G
being opened until the bolt A is retracted by the action of the spring F.
In lieu of using a spring to retract the bolt which may be normally held shot by
au pressure acting on differential ai cas of the inner and outer side of the piston B,
the retraction of the bolt A may be effected by relieving the pressure on the roar
of the piston B or the unlocking may be effected by applying the au pressure
to the greater area, the connection of the pipe E to the cylinder (being in the
latter case suitably made and the rear of the piston B having an extension which
passes through an air tight cover on the cylinder C.
The pipes on the several vehicles are coupled together in a manner well known as
applied to automatic brakes and the whole of the locking bolts are actuated
simultaneously by means of a cock in the guard's vau ou on the locomotive.
In the event of collision severing the tiain or breaking of the pipe connections
the doors automatically unlock.
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 15
-
The improved locking devices for railway cairage doors constructed and
arranged to operate substantially as described.
Daved Line 20th dov at
LONE
WALLACE FAIRWEATHER,
Chartered Patent Agent,
62 St. Vincent Street, Glasgow, Agent for the Applicant.