Year: 1888

page_text: I, THEODORE MARTIN of Wallaceburg in the County of Kent and Province of
Ontario, Dominion of Canada, Gentleman, 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 :-
This my invention relates to a new and improved door lock; which invention
consists in the peculiar construction, arrangement and combination of the parts,
hereinafter described and set forth in the claims.
I now proceed to describe my said invention, reference being had to the accom-
panying drawings and the figures and letters of reference marked thereon, similar
letters indicating like parts throughout.
Fig. 1. is an elevation of my improved lock with the cover removed to show the
parts in this elevation the lock is shown with the parts in position as when locked
by the key and night latch. Fig. 2 is an elevation showing the parts of the lock in
the position when unlocked and free to be operated by the door handles. Fig. 3 is a
cross section taken on the line x x of Fig. 1. Fig. 4 is a corresponding cross section
showing the night latch as arranged for a mortise lock. Fig. 5 is a cross section on
the line y y of Fig. 2.
The mechanism comprising this my improved lock is contained within a suitable
casing A, of ordinary construction, which has a cover A¹ (Fig. 5) held in position by
a screw entering the boss a.
The latch B is for the most part of ordinary construction, being formed with
spindle cranks b adapted to operate with an ordinary spindle B¹ in the usual and
well known manner.
The latch B is however formed with two shoulders 6'6² as
shown.
The night latch C consists of a piece of metal formed with a handle c and a wing C³,
which, when turned into the position shown in Fig. 1 comes into contact with the
shoulder and prevents the latch from being operated by the door handles. The
wing C", when thrown back (Fig. 2) rests against a suitable projection c² on the
casing. The night latch enables the latch B to be locked from the inside of the door
independently of the key bolt, thereby preventing the door being opened after being

page_text: unlocked with a key from the outside. When the lock is mortised in the door as
shown in Fig. 4, the handle c is made separately from the night latch, and may be
adapted to engage therewith by means of a square shank e² in the manner shown. A
suitable spring B situated between lugs d, d¹, d, serves to return the latch when
operated by the door handles, by bearing with a constant pressure upon the shoulder b³
of the latch B. By this arrangement I am enabled to use a longer spring than has
hitherto been customary, and its liability to weaken is thereby reduced.
The key-bolt E is for the most part of ordinary construction, but is formed with an
upwardly projecting piece E¹, which, when in the position shown in Fig. 1, bears
against the spring D and locks the latch bolt B. The key bolt E operates in conjunc-
tion with one or more tumblers F pivoted at fand formed with the check piece F.
The tumbler or tumblers F operate either by their weight, or may be spring-pressed
by a spring F held between lugs f'. The key having been inserted through the key-
hole G, and turned in the lock, it is brought to bear upon the portion f* of the tumbler F
and one or other of the portions e of the key holt E. The tumbler is then lifted
around the pivot until the projection of the key-bolt clears the check-piece F,
when the key bolt may be reciprocated in either direction: the check piece F¹ retaining
it either locked or unlocked.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is performed, 1 declare that what I
claim is :-
1st) In a combined latch and lock, the combination of the latch provided with the
shoulder and the interior key-bolt E having the upwardly projecting piece E¹
adapted to engage with the shoulder 62 on the latch substantially as and for the
purposes set forth.
2) In a combined latch and lock, the combination of the latch having formed thereon
the shoulder, the latch-spring D operating against the shoulder and secured in a
vertical position on the face of the case,. and the interior key bolt E provided with the
upwardly projecting piece E', all combined to operate substantially as and for the
purposes set forth.
3) In a combined latch and lock, the combination of the latch B having the
shoulders 2, the interior key-bolt E baving the upwardly projecting piece E'
adapted to engage with the shoulder 62, and the night latch C formed with the wing C
adapted to engage with the shoulder 6 all combined to operate substantially as and
for the purposes set forth.
Dated this 22nd day of December 1888.