Year: 1886

page_text: Date of Application, 8th Mar., 1886.
Complete Left, 7th Dec., 1886.
Complete Accepted, 25th Jan., 1887.
JACOB BAER Hasengasse 20 locksmith at Bockenheim Frankfort %m CONRAD
KOESTER alte Mainzergasse 21 locksmith at Frankfort m do hereby declare the
nature of this invention to be as follows:-
The Safety Lock consists in its principal parts of the Bolt a and the catches d and f
On putting the key fig. 7 into the lock and turning it round as far as the catch d
fig. 1, this catch is lifted halfway out of the notch b of the bolt a and at the same time
the catches fig. 1 are raised, so that the smaller keybit with its various notches
(fig. 7) is brought to bear on the catches f fig. 1 and thus enabled to enter the notch
of the catch d lifting the latter entirely up.
We therefore request a patent:
On the connection of the catch d with the bolt a and the catches f; on the catch d in
relation to the catches f: on the connection of the spiral spring c with b and d.
The catches are a number of safety levers, unequally notched at f¹, which during
the action of the larger keybit on catch d, rise spontaneously; their various notches
being at the same time so regulated by the wards of the smaller keybit as to admit of
their entering at d¹ into the catch d, and this permitting the further action of the
larger keybit.
If the safety levers do not enter exactly they come into collision with the catch d,
hindering its further movement or preventing its liberation from the notches of the
bolt.
JACOB BÄR.
CONRAD KÕSTER.

page_text: We, JACOB BAR, lock manufacturer, of 20 Hasengasse, Bockenheim, Frankfort-on-
the-Maine, and CONRAD KÖSTER, locksmith, of 21 Alte Mainzergasse, Frankfort-on-
the-Main, both of the Empire of Germany, 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 consists of improvements in lever locks and latches, and in keys for
the same, whereby locks and latches of this description are made more secure, and less
liable to be picked, or opened with false keys.
The principal feature in these improvements is that the key has a double bit, which
projects on both sides of its centre stem, and that this double bit engages at the same
time with one or more levers below the keyhole, and with another lever or interlocking
plate, called a "diametral catch plate," above the keyhole.
This diametral catch plate engages alternately with the bolt of the lock, and with
the lever or levers below the keyhole, in such a manner, that only a key having a
double bit of the exact size, and with the precise number of steps on the nose, can
disengage it from the bolt, and thus free the bolt so as to enable the lock to be locked
or unlocked.
This action of the diametral catch plate arises from its peculiar shape.
It is an irregular, hollow, semi-circle or crescent, with projecting studs or catches,
working on a pin or pivot.
On the key lifting one side of this diametral catch plate to free the bolt of the lock
which is held or locked by one of these catches, the other side of the catch plate is
drawn forward, and another catch attached to the plate must engage with a slot cut
in the lower lever or levers, before the bolt can be released.
The security of the lock depends therefore mainly upon the difficulty of so arranging
these lower levers, as to allow the lower catch access to the slot.
In their normal position these levers are held down by one horn of the diametral
catch plate, against which they are pressed upwards by springs, so as to follow the
lifted end of this diametral catch plate when raised by the key, until they are stopped
by the bit of the key, and they are so gated that only the precise steps of the lower
bit of the key will open the slot and allow the catch to enter.
It will be evident on consideration, that it is almost impossible to pick this lock,
since there is no clue as to the various distances at which the lower levers must be
held, in order to open the slot and admit the catch, without doing which, the bolt can-
not be opened.
Moreover while feeling for these lower levers, the operator must at the same time
lift the diametral catch plate, which makes the picking of the lock far more difficult to
accomplish.
In the accompanying drawings
-
Fig. 1. Shews a Mortice lock made on my improved principle, the top plate being
removed to show the interior

page_text: Fig. 2. Shows the key.
3.
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"
various parts of the lock.
The letter A Shows the locking bolt.
latch bolt.
springs.
diametral catch plate.
slot cut in the end of F, to receive the catch P, attached to D.
lower levers.
slots in the locking bolt to receive the catch Q attached to D.
follower.
B
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0¹ 0"
"
"
"
22
D
27
"
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"
"
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"1
22
"
"
"
"
"
"3
"
32
22
"
"
"
"2
"
"
"
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22
catch attached to D which engages with E.
catch attached to D which engages with G.
"
"
"
"
"
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12
وو
DEIGHUKPOR
upper bit of the key.
lower bit of same.
catch attached to D which engages with the upper side of F.
Having now particularly described and ascertained the nature of my said invention,
and in what manner the same is to be performed, I declare that what I claim is
1. A diametral catch plate, of irregular crescent shape, and fitted with studs or
catches, which engage with slots in the holt and levers of the lock or latch, as herein
explained and set forth.
2. A lever or series of levers beneath the keyhole, which engage with an upper bit
on the key, and contain a slot, which engages with a catch on the diametral catch
plate, as herein described and set forth.
3. The combination of a double bitted key with the foregoing diametral catch plate
and levers, as herein explained and set forth.
S. S. BROMHEAD,
97, Newgate Street, E.C.,
Patent Agent.