Improvements in Locks or Fastenings suitable for Railway Carriage and other Doors.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Locks or Fastenings suitable for Railway Carriage
and other Doors.
I, EDWARD SYDNEY LUARD, of the Bombay Baroda & Central India Railway,
Bombay, India, Locomotive Superintendent, do hereby declare the nature of
this invention to be as follows:-
This invention has reference to railway carriage and other door locks or fas-
tenings of the kind in which the shooting of the lock bolt is dependent upon
the movement of a plunger produced by bringing the outer projecting end of
the plunger in contact with a fixed striking plate in the act of closing the
door.
Now this invention has reference to a construction of door lock or fastening
of the kind referred to wherein the lock bolt is connected to the operating
plunger in such a manner that inward and outward movement of the plunger
will produce outward and inward movement respectively of the bolt but so that
both the bolt and plunger can nevertheless be moved inward independently of
each other in order that outward movement of the bolt can, in the act. of closing
the door to which the lock is applied, be arrested by the striking plate until
the bolt is brought over the slot therein, without interfering with the inward
movement of the plunger, and when the door is shut and locked the bolt can
be drawn back by a suitable handle or equivalent device independently of
the plunger which at this time will be held in its inner position by the striking
plate.
Locks or fastening devices of the kind described can be constructed in various
forms.
In one arrangement, the bolt and plunger are arranged to slide parallel to
one another in suitable guides within a box or case adapted to be secured to a
carriage door. The bolt and plunger are connected together by a lever that is
pivoted to the sides of the box or case and has one end engaged with a slot or
recess in the inner end of the bolt and the other arranged between an inner
projecting portion of the plunger and one end of a spring the other end of which
bears against the outer portion of the plunger. The plunger is normally held
in its outer position and the bolt in its inner position by a second spring which
may be arranged between the box or case and the plunger and acts to force
the latter outward. The two springs may conveniently be coiled wire springs
arranged parallel to one another. The lever is formed with a square hole through
its pivoted boss to receive a handle of any suitable kind. The arrangement is
such that the first-mentioned or compensating spring will allow of the plunger
moving inwardly whilst the bolt is held stationary in an endways direction and
of the bolt being moved inwards whilst the plunger is held endways, the secondly
mentioned spring acting to move the plunger outward and the bolt inward and
to hold these parts in their outer and inner positions respectively when the door.
18 opened.

page_text: The striking plate for use with the lock hereinbefore described is provided
as usual with a vertical inclined guiding surface, against which the outer ends
of the bolt and plunger act in the ordinary way during the closing of the door
carrying the lock.
In another construction of lock or fastening device according to this invention,
instead of making the inclined part of the striking plate against which the
bolt bears during the closing of the door, rigid, as usual, it is made movable,
as for example in the form of a spring flap to permit of the bolt being moved
fully outward by the plunger before the door is closed and ultimately slipping
past and engaging with the edge of the movable part when the door is fully closed.
In this case the first mentioned or compensating spring acts only to permit of
the bolt being moved inward whilst the plunger is held in its closed position by
the striking plate.
Improvements in Locks or Fastenings suitable for Railway Carriage
and other Doors.
I, EDWARD SYDNEY LUARD, of the Bombay Baroda & Central India Railway,
Bombay, India, Locomotive Superintendent, 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 reference to railway carriage and other door locks or fas-
tenings of the kind in which the shooting of the lock bolt is dependent upon
the movement of a plunger produced by bringing the outer projecting end of
the plunger in contact with a fixed striking plate in the act of closing the
door.
.
Now this invention has reference to a construction of door lock or fastening
of the kind referred to wherein the lock bolt is connected to the operating
plunger in such a manner that inward and outward movement of the plunger
will cause outward and inward movement respectively of the bolt, but so that
both the bolt and plunger can nevertheless be moved inward independently of
each other in order that outward movement of the bolt can, in the act of closing
the door to which the lock is applied, be arrested by the striking plate until
the bolt is brought over the slot therein, without interfering with the inward
movement of the plunger, and when the door is shut and locked the bolt can
be drawn back by a suitable handle or equivalent device independently of
the plunger which at this time will be held in its inner position by the striking
plate.
Locks or fastening devices of the kind described can be constructed in various
forms.
Fig. 1 of the accompanying illustrative drawings shews in vertical section on
the line A B of Fig. 2 part of a door and door frame with one arrangement of
lock or fastening according to this invention applied thereto the door being
shown in its closed position and locked.
Fig. 2 shows, in horizontal section, part of a door and door frame with the
lock or fastening shown in Fig. 1 applied thereto

page_text: In this arrangement the bolt 1 and plunger 2 are arranged to slide parallel
to one another in suitable guides 3, 3ª within a box or case 4 adapted to be
secured, as by screws, within a mortise in a carriage door 5. The bolt 1
and plunger 2 are connected together by a lever 6 that is pivoted to the sides
of the box or case 4, as by a circular boss 1" on the lever fitting a circular
hole in one side of the case, and has one end 6ª engaged with a slot or recess 1ª
in the inner end of the bolt 1 and the other end 6b arranged between an inner
projecting portion 2 of the plunger 2 and one end of a spring 7 the other end
of which bears against the outer portion of the plunger 2. The plunger 2 is
normally held in its outer position and the bolt 1 in its inner position by a second
spring 8 one end of which, in the example shown, bears against the box or
case 4 and the other end against the outer portion of the plunger 2 and acts
to force the latter outward. The springs 7, 8 may conveniently be made of coiled
wire and be arranged parallel to one another as shewn.
As will be seen the construction and arrangement of these springs are such
that the spring 7 will allow of the plunger 2 moving inwardly whilst the bolt 1
is held stationary in an endways direction and of the bolt 1 being moved inwards
whilst the plunger 2 is held endways, the spring 8 acting to move the plunger 2
outward and the bolt 1 inward and to hold these parts in their outer and inner
positions respectively when the door 5 is opened. The lever 6 is formed with a
square hole 9 through its pivoted boss 1" to receive a correspondingly formed
spindle carrying the door handle or handles.
10 is a striking plate for use with the lock herein before described. It is
fixed to the door frame 11 and is provided as usual with a vertical inclined or
bevelled guiding surface 10ª, against which the outer ends of the bolt 1 and
plunger 2 act in the ordinary way during the closing of the door 5, and with a
slot 10b arranged opposite a recess 11 in the door frame 11.
The working of the lock is as follows:-Upon closing the door 5, the plunger 2
will be forced inward against the resistance of the springs 7 and 8 by the striking
plate 10 which will also hold the bolt 1 in its inward position against the action
of the spring 7 until the door is completely shut and the bolt brought opposite
the slot 10 in the striking plate 10 and the recess 11" in the door frame 11,
whereupon the bolt will be shot forward by the spring 7 and the door locked.
Upon partially rotating the lever 6 in the direction of the arrow by a suitable
handle to unlock the door, the bolt 1 will be withdrawn from the recess 11ª
and slot 10b against the resistance of the spring 7, but the plunger 2 will still
be held in its inward position, against the action of its spring 8, by the striking
plate until the door is opened whereupon the spring 8 will act to move the
plunger 2 into its outer position and the bolt 1 into its inner position in which
relative positions the plunger and bolt will remain until the door is again closed.
Fig. 3 shows in horizontal section a part of a door frame provided with a
modified construction of striking plate. According to this construction instead of
making that portion of the inclined or bevelled part of the striking plate 10
against which the bolt 1 (Fig. 1) bears during the closing of the door, rigid, as
usual, it is made movable, as for example in the form of a spring flap 10° that
is pivoted to the fixed portion of the plate at 10 and is normally held in the
open position shown, by a spring 10° so as to permit of the bolt 1 being moved
fully outward by the plunger 2 before the door is closed, and ultimately slipping
past and engaging with the edge of the movable part 10° when the door is
fully closed. In this case the compensating spring 7 acts only to permit of
the bolt 1 being moved inward to unlock the lock whilst the plunger 2 is held in
its closed position by the striking plate 10.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:
1. A railway carriage or other door lock or fastening of the kind housin

page_text: to wherein the bolt is connected to the operating plunger in such a manner that
inward and outward movement of the plunger can cause outward and inward
movement respectively of the bolt when the same is free, but both the bolt and
the plunger can be moved inward independently of each other so that outward
movement of the bolt in the act of closing the door, can be arrested by the
striking plate until the bolt is brought opposite the slot therein without inter-
fering with the inward movement of the plunger, and after the door has been
locked the bolt can be drawn back by a suitable handle or equivalent device
independently of the plunger, which at this time is held in its inward position
by the striking plate, substantially as described.
2. A railway carriage or other door lock or fastening constructed and operating
substantially as hereinbefore described with reference to and shewn in Figs. 1
and 2 of the drawings annexed.
3. The modified construction of railway carriage or other door lock or fastening
wherein that portion of the inclined part of the striking plate against which
the bolt will bear during the closing of the door to which the lock is applied
is made movable so that the bolt can be moved outward by the plunger before
the door is closed and will ultimately slip past and engage the edge of the
movable part when the door is fully closed, substantially as hereinbefore described
with reference to Fig 3 of the drawings annexed.
For the Applicant,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.