CERTAIN IM- PROVEMENTS IN THE CONSTRUCTION OF LOCKS, LATCHES, AND SUCH LIKE FASTENINGS, APPLICABLE FOR SECURING DOORS, GATES, WINDOWS, SHUTTERS, AND SUCH LIKE PUR- POSES
Year: 1840

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
CLARK, of Wolverhampton, in the County of Stafford, Iron Founder, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Hor
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Twenty-second day of October, in the fourth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Thomas Clark, Her especial licence, full power, sole privilege
and authority, that. I, the said Thomas Clark, my executors, administrators,
and assigns, and such others as I, the said Thomas Clark, my executors,
administrators, or assigns, should at any time agree with, and no others,
from time to time and at all times during the term of years therein men-
tioned, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, and in all Her
Majesty's Colonies and Plantations abroad, an Invention of "CERTAIN IM-
PROVEMENTS IN THE CONSTRUCTION OF LOCKS, LATCHES, AND SUCH LIKE FASTENINGS,
APPLICABLE FOR SECURING DOORS, GATES, WINDOWS, SHUTTERS, AND SUCH LIKE PUR-
POSES," being a communication from a foreigner residing abroad; in which
said Letters Patent is contained a proviso, obliging me, the said Thomas
Clark, by an instrument in writing under my hand and seal, particularly to
describe and ascertain the nature of the said Invention, and in what manner
the same is to be performed, and to cause the same to be inrolled in Her
Majesty's High Court of Chancery within six calendar months next and

page_text: immediately after the date of the said in part recited Letters Patent, as
in and by the same, reference being thereunto. had, will more fully and at
large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Thomas Clark, do hereby declare that the nature of the said Invention, and
the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say):-
This Invention consists in the substitution of weights or weighted levers
instead of the springs usually employed in locks, latches, and such like fasten-
ings, for the purpose of keeping the bolts in their proper positions after
having been shot by means of a.key..or other instrument in the usual manner.
Fig. 1, in the accompanying Drawings, represents the interior of a lock, the
plate or cover being removed, all its parts being shewn as in a quiescent state,.
the lock bolt being removed, and its situation shewn by dots.
Fig. 2 represents the lock bolt as just about to-be-shots forward the brass
tumbler and weighted: lever having been raised by means of the key, in order
to allow the bolt to pass the key having performed half a revolution.
:
Fig. 3-shews the lock bolt shot forward into the box; or the door-jamb, the
key having performed an entire forward revolution.
Fig. 4 represents the lock with the bolt thrown or forced back, the key
having performed a reverse revolution. The catch bolt in this Figure is also
shewn as drawn back into the lock, and the door at liberty to be opened.
a, a, a, a, is the box or casing of the lock, containing the moving parts; b, b, is s
the lock bolt; c, c, is a tumbler turning loosely on a centre at d; a.weighted
lever e, e, is also mounted on the same centre, and has two studs or projections;
fand g, formed on.it for the purpose of catching or taking into an opening or
recess made in the lock bolt, and retaining the same in any position in which
it may be placed; h, h, is the ordinary catch or latch bolt, and is moved by a
handle in the usual manner; to the inner end of this bolt a weight, or rather
(as it may be termed) a weighted lever i, is.connected. by a joint. This' lever
is mounted: on: a centre or fulcrum at j; the spindle of the handle of the
lock is shewn at k, and has two small levers 7, 1, attached to it at-right angles,
or nearly so, to each other, and are for the purpose of raising the weighted
lever i, and withdrawing the catch bolt into, the lock when the door is.required
to be opened. The different parts of the lock being in the position shewn in
Fig. 1, and the lock bolt as seen by dots, the key is to be. introduced into the
lock and turned half-way round in the direction of the-arrow, for the purpose

page_text: of raising the brass tumbler c, c, and weighted-lever 6, 65 so-as-to-release
the studs f and g, from the recesses or openings formed in the lock bolt;
this having been effected the different parts of the lock will assume the posi
tion shewn-in Fig. 2, and upon continuing the motion of the key, the end of.it
being in contact with the lock bolt, the latter will be shot forward, and from
the peculiar form of the under part of.. the tumbler and weighted,lever.e, e;
these two-parts-are-kept elevated while the bolt is being shot forward by the
key, when the studs' f and g..are.again allowed.to.descend into their proper
places-in-the other notches or recesses, and prevent the bolt from being moved
or returned without the agency of the key. Whenever the lock bolt is with:
drawn upon the door being required to be opened, then the catch, bolt is,with-
drawn also by turning the handle either way, which, by means of the small
levers 7, 7, attached to its spindle,, raises the weight i, and draws in the catch
bolth, h, into the position shewn in Fig. 4.
Fig. 5 represents another modification of the improved lock and latch bolt
fastening; the positions. of the different parts in this Figure correspond to
those shewn in Fig. 1. Fig. 6 is another view of the same, and corresponds
to Fig. 2. Fig. 7 is also a view of the same lock, the parts in this Figure
being in the same relative positions as those in Fig. 8. Fig. 8 represents
both the lock bolt and catch bolt as withdrawn for the purpose of allowing
the door to be opened; the several parts of. this. Figure correspond in
relative positions with those shewn in Fig. 4. Similar letters of reference
are marked on corresponding parts in the several Figures of both these
constructions of locks; therefore, the modifications shewn in Figs. 5, 6, 7,
and 8, will be perfectly understood by referring to the description of Figs. 1,
2, 3, and 4. In the accompanying Drawings I have shewn only one tumbler
as applied to this improved construction of lock or fastening, but it is evident
that two or more may be employed if it is required to make the lock more
secure; but if merely a common door lock is required, it may for economy be
made without any tumbler whatever, the weighted lever e, e, upon which the.
studs fand g are formed, being a sufficient protection against opening the lock
surreptitiously. It will be evident to all lock-makers that the arrangement of
the different parts may be varied without departing from the nature. of the.
Invention; I do not, therefore, confine myself to the precise arrangements or.
construction of the parts shewn in the Drawing.
Having now described the nature and construction of these improved locks,
latches, and such other fastenings, I would in conclusion remark that it will
be evident that the same may be applied in like manner as fastenings to.
windows, commonly called "French casements," or those opening on hinges.

page_text: like a door, as well as to those opening by moving up and down as sashes, by
placing the lock, latch, or bolt (in this instance) on the side bead or panel of
the window, and forming a recess or mortice in the sash, into which the bolt
will be shot by the weighted lever when the window is shut down; but the
bolt will be kept back or within the case of the lock when the window is
open without any other agent or part, the end of the latch or bolt being in
contact with the plain part of the sash. And I claim as the Invention secured
-to me by the herein-before in part recited Letters Patent, the substitution of
weights or weighted levers for springs in the construction of locks, latches, and
other fastenings, in the manner above described.
In witness whereof, I, the said Thomas Clark, have hereunto set.my
hand and seal, this Twentieth day of April, in the year of our Lord
One thousand eight hundred and forty-one.