Improvements in Looks and Latches.
Year: 1894

page_text: Date of Application, 6th Oct., 1894-Accepted, 10th Nov., 1894
COMPLETE SPECIFICATION.
Improvements in Looks and Latches.
I, WILLIAM ELDER of 151 Strand, London, W.C., Consulting Engineer, do
hereby declare the nature of this invention (a communication to me from James
W. McKee of 431 and 433 Broadway, Brooklyn, in the County of Kings and
State of New York, United States of America, Inventor) and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement::-
This invention relates to improvements in looks and latches, and refers more
particularly to that class of locks and latches which are operated by the direct
end wise movement of the key in distinction from those in which the key is required
to be turned after it has been inserted in the key hole. The object of my invention
is to provide locks and,latches of the class referred to with means whereby said
looks and latches will be rendered practically unpickable and whereby the tumblers
cannot be operated sufficiently to move the bolts except. by means of the correct
key.
'
In order that my invention may be readily understood reference is made to the
accompanying drawings wherein. like letters indicate corresponding parts throughout
the several figures and in which--
Figure 1, represents a side elevation of my improved lock or latch, the tumblers
being in their normal or locked positions.
Figure 2, represents a plan view of Figure 1.
Figure 3, represents a side elevation of my improved lock or latch, the tumblers
being shown in their raised or unlocking positions and the key being inserted.
Figure 4, represents a plau view of Figure 3.
Figure 5, represents a side elevation of the tumblers B and C and the locking
tumbler M:
Figures 6 and 7, represent a side elevation or plan view respectively of the
tumbler C.
"
Figure 8, represents a side elevation of the tumblers A and E, both being of
similar construction.
Figure 9, represents a side elevation of the tumblers B and D both being of
similar construction, but the tumbler B is formed or provided with a recess b³.
Figure 10, represents a plan view of the key.
In carrying my invention into practice I pivotally support a series of
tumblers A, B, C, D, E, on a common, pivot which pivot is fixed to the frames or
the like, L, within a suitably constructed lock case in any desired manner. The
tumbler C which is preferably thicker than the other tumblers is provided at its
rear part with a rearwardly extending arm G by means of which the motion of said
tumbler is transferred to any suitable mechanism by means of which the bolt of
the lock or latch is operated. The front end of the tumbler C is normally held in
contact with the rear face of the head H, by means of the springs a, b, operating
respectively on their relative tumblers A, B, D, and E which normally rest upon a
pin J fixed to the said tumbler C, the whole of the tumblers being capable of
being swung from the position shown in Figures 1 and 2, to that shown in Figures 3.
and 4.
For the purpose of operating the tumblers, I provide a key K which is adapted
to be passed through the key hole with which the head H is provided. The front
or operating end of the said key when being inserted comes in contact with the
extensions a¹, b'; c¹, d¹, e¹, and on said key being pushed quite
"home the
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page_text: ;
tumblers. A, B, C, D, E are caused to turn on their pivots, the extensions aª, bª,
c,d,e passing through suitable apertures with which the key K is provided.
For the purpose of making it practically impossible for the tumblers to be moved
separately and the lock thus picked, I pivotally support a locking tumbler M at a
convenient position between the frames L, which locking tumbler is normally held
in contact with the tumbler. C, by means of a, apring m. The said locking
tumbler M is bifurcated at its free end and is also provided with a projecting pin or
stud m' for the purposes hereinafter described. The tumbler C is recessed or cut
away as ate and is provided with. a pin or stud e', the arrangement being such that
if the said tumbler C be swung on its pivot the pin will enter the bifurcated
end of the locking tumbler. M and will thereby be prevented from being further
moved.
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In order to enable the said tumbler C to be swung to its full extent, I form the
projecting or extending part of the tumbler B of such a shape that when the
said tumbler is swung on its pivot the extending part 1 will engage with the pin m
and thereby raise the locking tumbler M until the bifurcated end thereof is raised
above the pin.c of the tumbler C, and in order that the said locking tumbler. M
shall be first raised a sufficient distance to enable the tumbler: C to be moved, I
form the key K with a projecting ward' or the like which will engage with the
said tumbler B and push it a sufficient distance to raise the locking tumbler:M
before the part of the key engages with the tumbler C. The part m2 of the
bifurcated end of the locking tumbler M is of sufficient length to be brought into
engagement with the sloping face of the tumbler C, so that the said locking
tumbler M will be retained in its raised position when the tumbler C is swung on
its pivot by the key. In order to ensure that the tumbler B shall not be moved: a
greater distance than is necessary to just sufficiently raise the locking tumbler M'as
described, I form the projecting or extending part 6 with a recess or the like the
arrangement being such that if the said tumbler B be. moved to a greater distance
than necessary, the pin m² of the locking tumbler M will be caused by the action
of the spring m to enter into the recess b³ thereby preventing the tumblers being
operated until the locking tumbler M has been lifted so as to free the tumbler. B
which can only be done by taking, off the lock.
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
claim is
In combination with a lock or latch having tumblers. A, B, C, D, E, adapted to
be operated by inserting a key K, means for preventing said tumblers. being
operated except by the right key, said means consisting of a locking tumbler M
having a bifurcated end, a spring m, pin or stud' m' an extending part m the
extending part of the tumbler B being formed or provided with recess or the
like the extending part c' of the tumbler C being formed or provided with a
recess or the like a part and pin c, all being constructed, arranged, and
operating for the purposes and substantially as described and illustrated.
Dated this 6th day of October 1894.
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