IMPROVEMENTS IN RIM, MORTISE, AND OTHER LATCH LOCKS
Year: 1876

page_text: LETTERS PATENT to Edgar Hum, of Stoke Newington, in the County of
Middlesex, for the Invention of "IMPROVEMENTS IN RIM, MORTISE, AND OTHER
LATCH LOCKS."
Sealed the 27th February 1877, and dated the 13th September 1876.
PROVISIONAL SPECIFICATION left by the said Edgar Hum at the Office of
the Commissioners of Patents on the 13th September 1876.
EDGAR HUM, of Stoke Newington, in the County of Middlesex.
MENTS IN RIM, MORTISE, AND OTHER LATCH LOCKS.".
"IMPROVE-
My Invention relates to improvements in rim and mortise door locks and other
latch locks, such as drawback locks and gate locks, and it has for its object to
dispense with the springs which in common latch and bolt locks act against the tail
end of the latch and on the tumbler of the bolt, and to substitute therefor a single
weight acting by gravity only, and applied in such manner as to fulfil the purposo
of both springs, thereby simplifying the construction of the lock and reducing the
liability to breakage which is inseparable from the use of steel springs. Tho
weight also serves when the bolt is shot to lock the latch.
In carrying out my Invention as applied to a im or mortise door lock of the
ordinary kind I dispense with the usual rigid shaped arm on the latch bolt behind
the follower, and in lieu thereof I joint the tail end of the latch bolt to an inverted
L shaped lever pivoted on a stud at its lower extremity, and having jointed to the
extremity of its upper or horizontal arm a flat weight which rests upon the tumbler
of the bolt when the lock is provided with one. This shaped lever lies behind the
follower, and is acted thereon to throw back the latch by the handle in the usual
way. The weight is connected to the horizontal arm of this lever by a rule joint
winch allows it to rise independently of the lever when the tumbler is raised by
turning the key, the gravity of the weight being at other times constantly exerted
on the L shaped lever and through it on the latch. When the bolt is shot by
turning the key a lug on the bolt enters a notch or slot on the weight or vice versa,
thereby holding the weight down and preventing the latch being thrown back by
turning the handle until the bolt is unlocked by the key.

page_text: SPECIFICATION filed in pursuance of the conditions of the Letters Patent, and of
an Order of the Lord Chancellor, by the said Edgar Hum in the Great Scal
Patent Office on the 21st March 1877.
EDGAR HUM, of Stoke Newington, in the County of Middlesex.
MENTS IN RIM, MORTISE, AND OTHER LATCH LOCKS."
"IMPROVE.
My Invention relates to improvements in latch locks of the ordinary cheap kind,
and is not applicable to lever or other expensive kinds of locks; it is designed more
especially for rim and mortise door locks and other latch locks, such as drawback
locks and gate locks, and it has for its object to dispense with the springs which
in common latch locks act against the tail end of the latch and on the tumbler of 1
the bolt, and to substitute therefor a weight applied in such manner as to fulfil
the purposes of both springs, thereby simplifying the construction of the lock
and avoiding the liability to breakage which is inseparable from the use of steel
springs.
In carrying out my Invention as applied to a rim or mortise door lock. I dispense 1
with the usual rigid L shaped arm on the tail end of the latch on which the
follower acts in ordinary locks, and in lieu thereof I joint the tail end of the
latch to an inverted shaped lever pivoted on a stud at its lower extremity, and
having its upper or horizontal arm weighted; this weighted arm rests upon the
tumbler of the bolt when the lock is provided with one This shaped lever les 2
behind the follower and is acted on thereby to throw back the latch by the handle
in the usual way. The tail end of the latch is jointed loosely to the L shaped
weighted lever (or the Intter in some locks merely rests against the tail end of the
latch without any joint or connection) to allow the weighted lever to rise sufficiently
to enable the bolt to be thrown back when the tumbler is raised by turning 2
the key
In the accompanying Drawings I have illustrated my Invention in two kinds of
locks as examples of its application.
Figure 1 is a face view of a rin: lock, the inside cover plate being removed to
show the parts, Figure 2 is a horizontal section of the same on line 1-1, Figure 1. 3
Figure 3 shows face and end views of the weighted L shaped lever detached.
Figure 4 represents an inside face view (with the cover plate removed), and
Figure 5, a horizontal section on line 2-2, Figure 4, of a drawback gate latch.
In Figures 1 and 2, A is the latch, and B, the dead bolt as usual in such locks,
except, that the latch has not the usual aim at the tail end. The bolt is partly 3
broken away to show the weighted lever which lies behind it; C is the follower;
D, the spindle, and E, the tumbler, all as usual; F is an inverted L shaped lever
pivoted at the lower extremity G, and having its upper arm enlarged in the form
of a flat weight H which works between the latch and bolt and the lock case, as
shown. This lever F is connected to the tail end of the latch by a stud I on the 4
lever received in a slightly elongated hole or slot K in the latch or vice versa.
The weight is extended downward at a point H¹ which rests upon the tumbler E
near its pivot, as shown. The slot K is of only just sufficient length to allow the
weight to be lifted slightly by the tumbler without moving the latch when the
tumbler is raised by turning the key in order to throw the bolt. The follower acts 4
on the vertical arm of the lever L which lies behind it in the position usually
occupied by the arm on the tail of the latch, and when the follower is turned by
the handle the weight is raised and the latch thrown back, as indicated by the
dotted lines.
It will be obvious that the Invention may be similarly applied to a latch
without any dead bolt or tumbler. In the drawback lock Figures 4 and 5 latch A
also acts as a bolt when shot by turning the key in the ordinary way, and there is
no spindle or follower. The other parts are indicated by the same letters of
reference as in the previous Figures. In this case the vertical aim of the lever F
has a slight curve or projection on the front edge which simply rests against the 5

page_text: return end A¹ of the latch bolt without being connected thereto, and the weight H
rests on the tumbler E, as in the former case. The action of the weight on the
latch and tumbler is the same as before.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is, the application and employment in
locks of the kind herein-mentioned of a weighted arm or lever acting by the force
of gravity on the latch, and also on the tumbler if there be one in lieu of springs,
substantially as herein described and shown in the Drawings annexed.
In witness whereof, I, the said Edgar Hum, have hereunto set my hand and
seal, this Fourteenth day of March, in the year of our Lord One thousand
eight hundred and seventy-seven.
EDGAR HUM
(L.S)