IMPROVEMENTS IN LOCKS AND LATCHES
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by Matthew Andrew at the Office
of the Commissioners of Patents, with his Petition, on the 18th
June 1869.
I, MATTHEW ANDREW, of Melbourne, in the Colony of Victoria, but
at present residing at Edgbaston, in the County of Warwick, Gentleman,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN LOCKS AND LATCHES," to be as follows:-
My Invention consists of the improvements herein-after described
in constructing and arranging the parts of locks and latches, whereby
the mechanism of locks and latches is much simplified, and the said
locks and latches are consequently manufactured more economically,
and are less liable to get out of order than locks and latches of the
ordinary construction.
In making a combined lock and latch according to my Invention
I construct and arrange the parts as follows:-The latch bolt is situated
at the bottom end of the vertical arm of a crank lever, the horizontal
arm of the said lever being situated immediately above the follower
fixed on the spindle of the latch. The said crank lever turns upon a

page_text: In
centre in the upper corner of the lock case, the said arms of the
lever being respectively parallel to one of the vertical and one of the
horizontal sides of the case when the lever is in its normal position.
By turning the knob of the latch spindle the follower raises the
horizontal arm of the crank lever and withdraws the latch bolt. Upon
the back of the case of the lock is a slide, which is acted upon by
the key in the way herein-after described, the said slide somewhat
resembling the bolt of an ordinary lock, but without a head. The said
slide works upon two pins or stumps on the back of the lock case.
The front end of the slide has a slot, into which one of the pins or
stumps takes, the said slot and pin or stump simply guiding the slide
in its nearly horizontal motion. At the rear end of the slide is a
rectangular opening in which the other pin or stump engages.
the middle of the said rectangular opening and on its upper side is
a projecting piece, the said opening and projecting piece somewhat
resembling the gating in the lever of an ordinary lever lock. The said
projection prevents the motion of the slide until rear end has been
raised in a nearly vertical direction to such a height as will bring the
bottom of the said projection above the pin or stump which engages
in the said opening. The under side of the rear end of the slide
is of a concave curved figure. The keyhole is situated beneath the
rear end of the slide. On introducing and turning the key for shooting
or withdrawing the slide its first. action is to raise the rear end of the
said slide vertically, next to move it horizontally, and finally to allow
it to descend vertically. By this action the projection described is
carried over the stump during either the shooting or withdrawing of
the slide. By the shooting of the slide its front end is brought against
the vertical arm of the crank lever carrying the latch bolt. and fixes
the said lever. The latch bolt consequently cannot be withdrawn.
On withdrawing the slide the said crank lever is free to move, and the
unlocking of the latch bolt is effected. By this arrangement the latch
bolt is made to perform the functions both of a latch bolt and a lock
bolt, the latch bolt having the function of an ordinary latch bolt when
the slide described is in its withdrawn position, and having the function
of a lock bolt when the slide is shot. A night bolt may work ou the
upper part of the lock case, and be made to fix the crank lever and
prevent the withdrawal of the latch bolt. The lever and slide take
the required vertical motions by the influence of gravity, but in order
more effectually to secure the required motions a spring may he

page_text: employed, one end acting against the top of the rear end of the slide,
and the other against the vertical arm of the crank lever. When it is
desired to employ a very short slide I make it of a crank form, a vertical
arm extending upwards and bearing against the crank lever of the
latch bolt near its joint. The gating described and the curved part on
which the key acts are situated in the horizontal part of the slide. The
action of this modification is essentially the same as that of the lock
first described,
The latch mechanism and lock mechanism described may be used
independently of each other.