Year: 1895

page_text: Date of Application, 31st Jan., 1895
Complete Specification Left, 29th Oct., 1895-Accepted, 30th Nov., 1895
I, HUGH DONALD FITZPATRICK, of 70 Wellington Street, Glasgow, Registered
Patent Agent, do hereby declare the nature of this invention to be as follows:-
This invention has reference to certain improvements on Fitzpatrick and
Kennedy's Patent No. 1152 of 1891.
In this invention instead of making the spring bolt with a tapering lug on its
upper side I make the tapering lug on the lower side, and I cut or make the
tumbling levers so as to correspond therewith and to allow room for the lug to
play laterally. The lower projecting tapered part of the boss head is made with
two tapers or curves on it, one in a horizontal plane, and one in a vertical plane.
The vertically tapered part, which corresponds to aud works upon or against the
tapered lug on the bolt, extends out a short distance beyond the horizontal tapered
part. The horizontally tapered part serves, as usual, to lift the tumbling levers
when the door is pulled to whilst the vertically tapered part serves to force back
the spring bolt. Under this arrangement the objectionable apper projecting boss,
as heretofore used, is done away with.
The pin for holding the bolt spring in place and also the flange on the bolt are
both extended out the full distance so as to prevent the spring falling down out of
position.
Instead of using a number of separate small springs for the tumbling levers one
single spring either entirely solid or cut into teeth at the lower end may be used.
The locking pin on the spring bolt is or may be lowered slightly so as to work
within the recesses in the tumbling levers and said recesses are preferably cut on
the slant and with the back side projecting up vertically at the top so as to form a
stop to said locking pin and prevent the bolt being shot back without at the same
time lifting the tumbling levers.
The bolt may for strength and resisting power be made with both upper and
lower curved legs.
If desired in order to effect the shooting back of the bolt when the door is pulled
to, one of the tumbling levers or an auxiliary lever having an inclined plane on it
may be used the inclined plane working against a pin in the bolt, or vice versa.
Dated this 30th day of January 1895.
H. D. FITZPATRICK,
70 Wellington Street, Glasgow, Agent.
1, HUGH DONALD FITZPATRICK of 70 Wellington Street, Glasgow, Registered
Patent Agent, 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 invention has reference to certain improvements on Fitzpatrick and
Kennedy's Patent No. 1152 of 1891.

page_text: And in order that my said invention may be properly understood I have hereunto
appended an explanatory sheet of drawings, whereon,
Fig. 1 shows the inside of the improved door latch with the levers removed.
The levers are indicated in dotted lines. The bolt is shown as locked.
Fig. 2 is a like view but with the bolt shot back.
Fig. 3 is a view of the lock complete with its levers and bolt in the "locked"
position.
Fig. 4 is a front view, Fig. 5 a plan, and Fig. 6 a side view of the boss head.
In this invention instead of making the spring holt a with a tapering lug on its
upper side I make the tapering lug on the lower side and I cut or recess the
tumbling levers c on their under sides so as to correspond with and to allow room
for the lug to play laterally as shown at c¹ Fig. 3. The lower projecting tapered
part or boss d of the boss head d is made with two tapers or curves d³, d³, on it,
one in a horizontal plane and one in a vertical plane. The vertically tapered
part d³, which corresponds to and works upon or against the tapered lug 6 on the
bolt, extends out a short distance beyond the horizontally tapered part d². This
projecting tapered part d³ can also he tapered horizontally on its upper side as
shown at d. The horizontally tapered part d² serves, as usual, to lift the tumbling
leverse when the door is shut whilst the vertically tapered part d³ serves to force
back the spring bolt a. Under this arrangement the objectionable upper projecting
boss, as heretofore used, is done away with.
The pin e for holding the bolt spring in place and also the flange e¹ on the bolt
are both extended out the full distance and against the back plate so as to prevent
the spring falling off the pin and down out of position.
Instead of using a number of separate small springs g for the tumbling levers
one single spring either entirely solid or cut into teeth at the lower end may be
used.
The locking pin on the spring bolt is, or may be, lowered slightly so as to
normally rest when the levers c are down, in a recess 2 cut in the levers and thus
prevent them being lifted without first shooting back the bolt. The recesses i are
preferably cut on the slant as shown and with the top part (Fig. 3) of the back
side or incline projecting up vertically so as to form a stop to said locking pin and
prevent the bolt being shot back the full distance without at the same time lifting
the tumbling levers.
In the view Fig. 3 the full lines show the position of the bolt when the latch is
locked and it will be seen that if a person, by means of a knife or other instrument,
attempts to force back the bolt a he will not be able, under any circumstances,
without first lifting the levers c, force it back further than the dotted line j as the
pin will, as indicated in dotted lines at ', catch against the projection or stop i¹.
The dotted and full lines Fig. 2 show the relative positions of the pin and recess i
when the latch is unlocked.
The bolt may for strength and resisting power be made with both upper and
lower curved lugs b.
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 I consider
novel and desire to claim is :-
1. The general arrangement and combination of parts of the lock substantially
as herein before described and shown on the drawings annexed.
2. In a lock or latch the combination of the spring bolt, the recessed levers, and
the boss head with its double curved boss substantially as herein before described
with reference to the drawings annexed.
Dated this 28th day of October 1895.
H. D. FITZPATRICK,
70 Wellington Street, Glasgow.