Improved Means or Apparatus for Holding Railway Carriage Door Lights and other Sliding Windows in any Required Position.
Year: 1891

page_text: Date of Application, 26th May, 1891-Accepted, 11th July, 1891
COMPLETE SPECIFICATION.
Improved Means or Apparatus for Holding Railway Carriage Door
Lights and other Sliding Windows in any Required Position.
BOWMAN MALCOLM, C.E., Chief Engineer's Office, Belfast and Northern
Counties Railway Station, Belfast, and WILLIAM PENNINGTON, Manufacturer
aud Agent 24 Great Victoria Street Belfast 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 :-
Our invention relates to an apparatus which we let into the sides of the doors of
railway or other carriages, and which being in contact with the frame of window
or sliding light, holds the latter in any required position.
The form of apparatus which we now consider most suitable for the purpose,
consists of a metal casing, hinged at one end and bearing upon a spring at the
opposite end and having a graduated cavity, in which is placed a roller with central
projections, so formed as to be securely held in the cavity by means of small ribs
along the inner sides or edges of the said cavity or casing; the latter being secured
to a plate and let into the side or outer edge of a carriage door, in such a position,
that when the window or light, is being raised, the roller in the graduated cavity is
held in the deepest part, but when being lowered the roller is drawn down into the
smaller part of the cavity, by the downward pressure due to the weight of the
window or light, and thus holds the latter in any required position.
An increase of the downward pressure will overcome the resistance of the spring
bearing, and permit the window or light to be lowered, and in order that the window
may be lifted with ease, when it is at its lowest position, we make a small recess in
the window frame, opposite the apparatus in the door stile, which said recess will
allow the roller to be drawn upwards without resistance.
In order that our invention may be more particularly described and fully under-
stood, we shall now refer to the figures and letters of the accompanying drawings.
Fig. 1 represents the apparatus complete and the letters refer to the position of
the separate parts.
A, is the base plate which is secured to the side or edge of a carriage door
by screws at each end. B, a metal casing which being hinged at O, permits the
free movement of the opposite end, bearing upon a spring (N) at R. The graduated
cavity C, has small ribs D, on the inner sides or edges, which confine the roller E
in its place. The case B, at the end O, is engaged with the socket H by a pin, and
into the socket H, the adjusting screw F is screwed; having first passed through
the plate A, and being held there free to turn either to the right or left, without
entering or receding by means of a clamp or pin G, it thus regulates the distance
of the case B, from the plate A. In order that the contact of the roller E, may
be as free from rigidity as possible, a spring N, is placed on the screw L, and resting
upon the adjusting nut M, is pressing against the case B, at the free hole R, thereby
compensating for sudden or extra pressure.
The roller E is made with its diameter about equal to the deepest part of the
graduated cavity, but its diameter being greater than the shallow or smaller part
of the cavity, it consequently projects when forced down by the pressure due to the
weight of the window, and therefore checks, or retards the downward movement,
but when the window is lifted up, the roller is drawn into the deepest part of the
cavity thereby allowing the window to be lifted up with ease.
Having now particularly described and ascertained the nature of our said inven-
ion, and in what manner the same is to be performed, we declare that what we
laim is :-
1st. The apparatus consisting of a metal case of the form described or similar,

page_text: having a graduated cavity, which may be about one eighth of an inch deeper at
one end than at the other, and in which is placed a suitable roller; the whole being
secured to a base plate A, and let into the side or door stile of a railway carriage
door, or window frame.
2nd. The adaptation of the apparatus to the outer edge of a carriage door, and
the means of adjusting the same by a screw from the outside of the base plate A. F.
3rd. The device of making a small recess in the window frame directly opposite
the said apparatus when the window is in its lowest position, so that the window or
light may be lifted with ease.
Dated this 10th day of Mar 1801
B. MALCOLM.
WM. PENNINGTON.