Year: 1886

page_text: Date of Application, 30th Oct., 1886
Complete Left, 30th July, 1887.
Complete Accepted, 30th Aug., 887.
I, CHARLES SPENCER MADAN of Mansfield Chambers, Saint Ann's Square Manchester,
in the County of Lancaster, Engineer do hereby declare the nature of this invention
to be as follows:-
My Invention relates to an improved construction of spring locks suitable for
Railway Carriage doors, coach doors and the like.
The lock consists of a casing of brass or other suitable material in which is placed
a bolt provided with trunions on which it is free to turn through a portion of a circle.
The bolt is provided with a lip which projects beyond the edge of the casing when the
bolt is at the point of rest. A movable hinge is fitted inside the case so as to be
always pressed against the end of the bolt by a spring. The projecting lip on the bolt
is bevelled so that when the door to which the lock is fixed is slammed the bolt is forced
back into the lock and released when the door is closed, thus latching the door
automatically. The door may then be more securely fastened by turning the bolt with
a key or handle.
Dated this 20th dow of October 1886

page_text: I CHARLES SPENCER MADAN, of Mansfield Chambers, St. Ann's Square, Manchester,
in the county of Lancaster, 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 :-
My invention relates to an improved construction of spring locks suitable for railway
carriage doors, coach doors, and the like.
The construction will be best understood by a reference to the drawings attached
hereto which represent sectional views of locks constructed in accordance with my
invention. The lock casing A A is of brass or other suitable material and within it
is placed a bolt or latch B of steel or suitable metal provided with trunnions & supported
in bearings formed on either side of the casing A on which it may be freely turned
through the required arc. The bolt B is preferably made of the form shown and is
provided at its free end with a bevelled lip B' which projects through the face of the
casing when the bolt is at rest, the degree of such projection is determined and may
be adjusted by the angle at which the base of the bolt is formed in relation to its
length.
According to one arrangement a movable hinged lever C is fitted inside the casing
and is always pressed against the base of the bolt B by a spring D and the said base
is so shaped that the pressure of the spring D and lever C always tend when the bolt B
is turned slightly on its trunnions either way, to return it to normal position. When
the door to which the lock is fixed is slammed the bevelled lip B¹ taking against the
usual striking plate forces back the bolt B into the casing to the position shown dotted
in the figures against the pressure of the spring D, but when the door is quite closed
the action of spring D causes it at once to be automatically latched. The door may
then be more securely fastened by a further turning of the bolt B in the same direction
with a key or handle applied at its centre of rotation in the usual manner, and opening
is effected by the turning thereof in the reverse or backward direction. For extra
security the bolt B when thus turned may be again locked as shown in figure 2 by
means of a small cam E which is made of suitable figure and also provided with
trunnions bearing in the casing on which it is free to turn through a quarter of a
circle. When the cam E is raised it takes against the lower part of spring D and
prevents any compression thereof, thus any movement of the bolt B is also prevented;
but when it is in normal position as shown it is quite clear of the spring D and allows
free movement of the bolt B. A small spring F fixed in the casing A presses against
the base of cam E in such a manner as to prevent its resting in any intermediate
position. An alternative arrangement for obtaining the same result is illustrated in
Figure 3 in which the lower end of the bolt B is normally in contact with the
spring D¹ the action of which is equivalent to that hereinbefore described in reference
to figures 1 and 2. In order to effect the extra locking an angular projection B2 is
formed upon the lower part of the back face of the bolt B and a movable locking

page_text: arm E' is pivotted upon the casing in such position as to be normally clear of the
bolt B, but after the bolt B has been turned as described into the horizontal position
shown, the arm E¹ may be turned so that its foot e taking against the angular
projection B' operates directly upon the bolt B and prevents any movement thereof
until it is returned to normal position. The arm Ê¹ is acted upon by spring F¹ to
prevent it from assuming any intermediate position.
Having now particularly described and ascertained the nature of this invention and
in what manner the same is to be performed I declare that what I claim is :-
1. A spring lock constructed and arranged in either of the forms illustrated in
figures 1 and 2 of the annexed drawings and operating substantially as and for the
purposes set forth.
2. The combination and arrangement of parts forming the spring lock constructed
and operating substantially as described and illustrated by figure 3 of the drawings
annexed.
Dated this Thirtieth day of July 1887.
J. C. CHAPMAN,
70, Chancery Lane, London, W.C.,
Agent for Applicant.