IMPROVEMENTS IN LOCKS OR FASTENINGS APPLICABLE TO RAILWAY CARRIAGE DOORS AND ANTON"
Year: 1873

page_text: LETTERS PATENT to James Maxwell, of Dundee, in the County of
Forfar, North Britain, Clerk, for the Invention of "IMPROVEMENTS
IN LOCKS OR FASTENINGS APPLICABLE TO RAILWAY CARRIAGE DOORS AND
ANTON"
PROVISIONAL SPECIFICATION left by the said James Maxwell
at the Office of the Commissioners of Patents, with his Petition, on
the 11th December 1873.
I, JAMES MAXWELL, of Dundee, in the County of Forfar, North
Britain, Clerk, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN LOCKS OR FASTENINGS APPLICABLE TO RAILWAY CARRIAGE
DOORS AND OTHERWISE," to be as follows, that is to say :-
This Invention relates to locks or fastenings designed specially to
obtain safety without inconvenience and disadvantage in the case of
railway carriage doors, whilst it is also applicable in any other cases
wherein a self-fastening action is desirable.

page_text: The fastering detail of the lock is a latch or turning bolt fixed on the
shank or spindle of the handle as in a common form of railway carriage
door fastener. In the open position the handle and latch are vertical,.
the latter being within the lock case and flush with the outside of the
opening through which it projects when in the closed position. To
attain the closed position the handle and latch move through a quarter
of a circle so as to become horizontal, and a spring is applied to the
latch or spindle; such spring being, by preference, powerful enough to
close down the latch when the latter is free to move.
A weight may in some cases be combined with or used instead of the
spring to impart the closing tendency to the latch.
When the door is open the latch is prevented from closing by a sliding
piece or holder which fits easily against the square end of the latch.
This holder is pressed outwards into its holding position by a spring, and
it is formed with a bevilled outer end which projects through a slot in
the lock case, and which when the door is closed encounters the striking
plate in the door case. On thus encountering the striking plate the
holder is forced inwards until a cut-away part of its bottom side or edge
clears the corner of the latch, whereupon the latch instantly closes
down. On the latch being turned up to open the door it moves back
the holder until its square end becomes horizontal, and then the holder
is moved forward again by its spring over the latch. The holder may be
moved inwards by a projection on the striking plate instead of itself
projecting, or it may be acted on in any other convenient way on the
closing of the door.
As compared with some self-fastening locks the present one has the
following advantages, namely:-
1. The handle assumes the ordinary positions when open or closed,
and does not require to be kept strained against a spring whilst the door
is being opened.
2. The handle cannot be turned to the closed position without
closing the door (excepting with a special improper manipulation).
3. The closing of the door causes the fastening latch to be completely
11

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Maxwell in the Great Seal Patent Office
on the 10th June 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MAXWELL, of Dundee, in the County of Forfar, North Britain, Clerk,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of December, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said James Maxwell, Her special
licence that I, the said James Maxwell, my executors, administrators,
and assigns, or such others as I, the said James Maxwell, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
LOCKS OR FASTENINGS APPLICABLE TO RAILWAY CARRIAGE DOORS AND OTHERWISE,”
upon the condition (amongst others) that I, the said James Maxwell,
my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Maxwell, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompanying
Drawings, that is to say :--
My said Invention relates to locks or fastenings designed specially to
obtain safety without inconvenience and disadvantage in the case of
railway carriage doors, whilst it is also applicable in any other cases
whowain a colf factorine action is desirable
$3.

page_text: •
And in order that my said Invention and the manner of performing
the same may be properly understood, I hereunto append a Sheet of
explanatory Drawings to be herein-after referred to, and representing
various modifications of my improved lock or fastening. In these
Drawings the same reference numerals are used to mark the same or
like parts wherever they are repeated.
C
Figure 1 of the Drawings is a horizontal section of parts of an
ordinary railway carriage door 1 and door frame 2 with a modification of
my improved lock 3, and with the holding latch or tumbler 4 in the
position for holding the door shut.
Figure 2 is an inside elevation of the lock as with the covering plate 5
removed; and Figure 3 is an elevation as at right angles to Figure 2;
whilst Figure 4 is an elevation similar to Figure 2, but with the holding
latch 4 and handle 6 in a different position. The fastening detail of the
lock is a latch or turning bolt 4 formed with a boss 7 fitted to turn in
circular holes in the inner and outer vertical plates 5, 8, of the lock,
whilst a square eye is formed through the boss for the insertion of a
squared part of the spindle 9, having the handle 6 on its outer end,
which spindle may be secured and guided in any convenient or suitable
manner. In the open position the handle 6 and latch 4 are vertical,
as shown in Figure 4, the latter being within the lock and presenting
only a very slight projection 10 beyond the outer surface of the outer
end plate 11 of the lock, the use of which slight projection is herein
after explained. To attain the closed position the handle 6 and latch 4
move through a quarter of a circle so as to become horizontal, and a
spring 12 of a volute form is applied to the latch 4 by entering its
inner end into a notch in the latch boss 7, such spring being, by
preference, sufficiently powerful to completely close down the latch 4
when the latter is free to move. As long as the door is open the latch 4
is prevented from closing by a sliding piece or holder 13 (shown
separately in plan in Figure 5) which is formed with a heel 14 fitting
easily between the top of the lock case and the square corner of the
latch 4. This holder 13 is pressed outwards into its holding position by
a spring 15, shown as acting through a lever 16, and it is formed with a
bevilled outer end 17, as best seen in Figure 5, which projects through a
slot in the end plate 11, and which when the door is being closed
encounters the striking plate 18 in the door frame 2.

page_text: pin its outer end 17 being bevilled so that it rises on encountering a
projection provided for the purpose on the striking plate 18. The outer
end of the holder 13 is claw-shaped to catch and retain the latch 4, in
the manner indicated by dotted lines. One spring 12 is arranged to act
on both the latch 4 and the holder 13¹.
Figures 13 and 14 are elevations as at right angles to each other
showing a simple mode of applying an additional locking action in
connection with such latches 4 as those used in my improved fasteners.
A simple latch 20 is fitted between a pair of lugs 21 formed on the back
of the striking plate, and a blade spring 22 is applied so as to act on the
side or end of it. This latch 20 is made with a square eye for the
insertion of the ordinary guard's key, and when turned into the position
shown by full lines prevents the main latch 4 from being raised. The
application of a locking latch of this kind is shown by dotted lines in
Figure 2.
In order that a person inside of a carriage may know whether the door
is fastened or loose, it will be of advantage to provide an inside indicator
such as a plate fixed on the handle spindle 9 at its inner end, such plate
having on it the words "shut" and " open," one of which appears at an
opening in a covering plate according to the position of the handle.
As compared with some self-fastening door locks, my improved one
has the following distinguishing and advantageous features:-
1. The handle assumes the ordinary positions when opened or closed,
and the lock cannot be left partly closed.
2. The handle cannot be turned to the closed position without closing
the door (excepting with a special improper manipulation).
3. The closing to of the door causes the latch to be completely and
not partially closed.
Having thus particularly described my said Invention, and the
manner of performing the same, I have to state that I do not restrict
myself to the precise details herein described or delineated, but
that what I believe to be novel and original, and claim as the
Invention secured to me by the herein-before in part recited Letters
Patent is,―
1. The arranging or combining together of the parts of locks or. a

page_text: fastenings applicable to railway carriage doors, and otherwise in the
improved manner, substantially as herein-before described.
2. The combining of a latch or turning bolt and holder so that the
latter encounters the striking plate when the door is being closed, and in
consequence releases the latch which is then turned into its holding
position by a spring, substantially as herein-before described.
In witness whereof I, the said James Maxwell, have hereunto set
my hand and seal, this Ninth day of June, in the year of
our Lord One thousand eight hundred and seventy-four.