IMPROVEMENTS IN AND CONNECTED WITH DOOR LOCKS FOR OPENING SAME ELECTRICALLY OR PNEUMATICALLY
Year: 1877

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, of the Firm of J.
Brandt and G. W. v. Nawrocki, of Berlin, Germany, Patent Agents, for the
Invention of "IMPROVEMENTS IN AND CONNECTED WITH DOOR LOCKS FOR
OPENING SAME ELECTRICALLY OR PNEUMATICALLY." A communication from
Alphons Lemke, of Aschaffenburg, Germany.
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 7th September
1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. v.
Nawrocki, of Berlin, Germany, Patent Agents. "IMPROVEMENTS IN AND CONNECTED
WITH DOOR LOCKS FOR OPENING SAME ELECTRICALLY OR PNEUMATICALLY." (A
communication from Alphons Lemke, of Aschaffenburg, Germany.)
Locks made according to this Invention are especially applied to doors such as
street doors and office doors, and are so arranged that they may be opened from
any desired place by means of an electric current or by air pressure. Existing locks
may also, according to one part of this Invention, be adapted to this purpose.
The bolt is withdrawn by being connected to one end of a double-armed lever,
which I call the bolt lever, to the opposite or lower end of which a pulling spiral
spring is connected, and this lower end is when the door is shut held against a
projection on the boss of another, which I call the detent lever, and which rests
against one end of an armature or keeper lever, the other end of which operates
against two electro-magnets, and is attracted by them when the current is sent
through, a spiral spring withdrawing it when the current is interrupted; the keeper
can be regulated by a set screw; the lever and bolt are then withdrawn by the
spiral spring aforesaid.
As arranged for pneumatic action the detent lever is drawn out of connection by

page_text: a double-armed lever, which can be raised by an india-rubber hollow column actuated
by air pressure, as is well known. While the bolt lever pulls the latch out of the
door post another bolt is thereby thrown forward; this bolt has a wedge-shaped
nose, which, coming against a correspondingly formed projection on the door post,
causes the door to open; this bolt also serves to set the whole mechanism for the
next operation when the door is slammed to, a spring on its tail pushing the bolt
lever back again. A spring pushes the bolt out. The bolt can also be opened by
key, or knob, or handle.
As applied to existing locks, a bolt is added, against which one end of the bolt
lever works, the other end being drawn back by the keeper lever of the electro-
magnet, which is fitted with a catch or nose; there is a second bolt which then
springs forward, and which on the slamming of the door sets the mechanism afresh,
that is, pushes the first bolt out, a spring brings it back when released, another spring
tends to push out the second bolt; a projection on the bolt lever pulls the latter
with it.
The mode of action for the pneumatic arrangement is analogous to the first-described
arrangement.
For an ordinary door latch the latter is raised out of the staple for opening the
door by means of a spiral spring at the opposite of the latch fulcrum, but to do this
it must first be released from a projection or nose near the fulcrum of another lever,
which is held by the keeper lever of the electro-magnet, or by the lever actuated
from the india-rubber column in the pneumatic arrangement. The latch coming
against the knob on the staple when the door is slammed causes the mechanism to
be set afresh. The latch is also held down by a spring at or near its fulcrum.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Gerard Wenzeslaus von Nawrocki in the Great Seal Patent Office
on the 19th March 1878.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. v.
Nawrocki, of Berlin, Germany, Patent Agents. “IMPROVEMENTS IN AND CONNECTED
WITH DOOR LOCKS FOR OPENING SAME ELECTRICALLY OR PNEUMATICALLY." (A
communication from Alphons Lemke, of Aschaffenburg, Germany).
Locks made according to this Invention are especially applied to doors such as
street doors and office doors, and are so arranged that they may be opened from any
desired place by means of an electric current, or by air pressure. Existing locks
may also, according to one part of this Invention, be adapted to this purpose.
Figure 1 of the accompanying Drawings shews a lock in the opened, and Figure 2
in the closed position, operated by electricity.
Figures 3 and 4 shew a similar lock operated pneumatically.
Figures 5 to 8 illustrate the application of this Invention to an existing lock to
be operated by electricity.
And Figures 9 and 10 shew the same lock to be operated pneumatically.
In each case the lock is shewn once in the closed, and once in the opened
position.
I will now proceed to describe the new parts.
Referring to Figures 1 to 4, A is the bolt which is drawn back by the double-
armed lever B and the spring C, which is in tension. The lower end a of the lever B,
when the door is closed, rests against the projection b on the boss D of the detent
lever d, the latter again being held by the lever F as regards Figures 1 and 2, the
other end, F¹, forming the keeper for the electro-magnet G, and being attracted
by them when the current passes through. g is a spiral spring for drawing it back
when the current is interupted, and ƒ a set screw for regulating the armature or
keeper F¹.
In a similar manner, as regards Figures 3 and 4, the lever d is released by a
double-armed lever F³, actuated by an india-rubber hollow column H and by air
pressure, as is well known.
The action of these two locks is as follows, see Figures 2 and 4:- While the
lever B pulls the bolt A out of the door post, the bolt K is simultaneously pushed
forward, which serves to open the door; this latter has a wedge-shaped nose, which
then comes against and slides past a correspondingly formed projection k on the
striking plate on the door post, Figures 1ª and 2ª. This bolt K also serves to set
the whole mechanism for the next operation when the door is shut to. While being
pressed into the lock the spring i on it pushes against the projection i¹ on the bolt
lever B, and forces the latter back so that the end a of same takes its place against
the projection b on the boss D. The spring i is slightly raised by means of a peg i²
so as to pass by the projection i¹, and so that the lever B is released when opening
the door, see Figure 1. The bolt K is pushed out by the spring ³, while the end
of a turns the boss D and detent lever da little; the latter gets into such a position
that the lever F passes behind the lever d. The bolt A is so connected to the lever B
that it can be worked by a knob or handle inserted in the boss L, or by a key
inserted at m acting on the lever M.
The application of this Invention to existing locks for working them by electricity
is illustrated by Figures 5 to 8. O is a bolt, which is added, and o' a bolt lever,
one end of which works against the bolt O, while the other end is held by the keeper
lever F of the electro-magnet G (the keeper F being formed with a nose or catch).
K is a second bolt which then springs forward; this bolt K serves to reset the
mechanism, that is, pushing the bolt O out when the door is slammed; is a spring
for pushing the bolt K out, and C is a spring for pushing the bolt O in when
released; is a projection on the bolt lever O', serving to set the apparatus as before
described with reference to Figs. 1 and 2.

page_text: Figure 7 shews the striking plate constructed according to this Invention.
Figures 9 and 10 illustrate the application of this Invention to existing locks for
working them pneumatically; this is quite analogous to the arrangement described
with reference to Figures 3 and 4.
Fig. 10a is a plan of the india-rubber hollow column H; and Figs. 10b and 10º,
side views of same, shown respectively in the raised and lowered position.
Figures 11 to 15 illustrate the application of this Invention to an ordinary door
latch, with staple.
R is the latch, and Z the staple; the latch turns on the fulcrum R¹, and T is a
continuation of the latch R on the opposite side of the fulcrum; T¹ is a spiral spring
tending to raise the latch R; and R, a spring tending to depress it; the arm T is
held by the nose or projection 8 near the fulcrum of the lever u, which is held by
the keeper lever u³ in the electric arrangement, see Figures 11 and 12, or by the
lever in the pneumatic arrangement, Figures 14 and 15, actuated from the india-
rubber column H. The latch R, coming against the knob on the staple Z when the
door is shut to, causes the mechanism to be set afresh, as before described.
And having thus described and ascertained the nature of this Invention, I declare
that I claim as the Invention communicated to me,-
Firstly. The application to door locks of lever combination actuated by an electro-
magnet, or by an india-rubber column for withdrawing a bolt, and simultaneously
causing another bolt to be pushed forward, which latter bolt, when the door is shut
to, resets the mechanism, as set forth.
Secondly. The modification for ordinary door latches, as described.
Thirdly. The construction of the striking plate, as described.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have here-
unto set my hand and seal, this Second day of March, in the year of
our Lord One thousand eight hundred and seventy-eight.