Improved Means of Preventing the Picking of Door-locks.
Year: 1895

page_text: PROVISIONAL SPECIFICATION.
Improved Means of Preventing the Picking of Door-locks.
We, JOSEPH RICHARD PARKER, of 1, Beaconsfield Terrace. Church End,
Villesden, London N.W. Photographic Accessory Maker, and FRANK BISHOP,
f the Firm of Marion and Co. of 22, and 23, Soho Square London W.,
Photographic Manufacturers, do hereby declare the nature of this invention to
be as follows :-
This invention relates to a device primarily intended for hotel bedroom doors for
preventing the unlocking of the door from the outside whilst the occupant of the
chamber is asleep, either by picking the lock or by turning the key supposing it to
ave been left in the lock. The device may be said to consist of a keyhole stopper
which is adapted to be passed completely across the lock from front to back so as
to effectually prevent the key (should it have been left in the lock) being turned
by any instrument applied from the outside, and by stopping up the part of the
keyhole which gives passage to the key-bit prevent the introduction of a skeleton
key or pick-lock should the key have been withdrawn.
The device, which is adapted to fold into a flat portable form such that it may
be conveniently carried in the waistcoat pocket, consists of a scutcheon plate
adapted to cover the keyhole (except that part which gives passage to the key-
shank) and in this scutcheon plate is pivoted an arm adapted to lie flat with the
plate or to stand out perpendicularly therefrom when it is inserted in the keyhole,
said arm then passing completely across the lock-case, its forward extremity
terminating in an enlargement or head forming a stopper for the keyhole next the
outer side of the door, this head being of such shape as to enable it to be readily
passed through the keyhole and cause any pick-lock that it may be attempted to
insert, to be deflected without allowing it to pass through the keyhole.
In order to secure the device in position, a key-shaped fastener is provided, the
shank of which is free to turn and slide in a hole in the scutcheon plate immediately
below the joint of the arm above described, and in order to admit of the bit portion
or lug of this fastener passing through the keyhole along with the arm the latter is
bevelled or recessed to receive the bit of the fastener which is correspondingly
hevelled so that when turned upwards it lies close alongside of and flush with or in
the plane of said arm so that in this position the two can be passed together through
the keyhole. When the bit of the fastener is thus passed into the interior of the
lock, the fastener is turned, say, a quarter round so as to bring its bit or lug out of
For this
register with the keyhole and into position to engage with the wall of the lock-case
against which it is tightly clamped by means of a tightening screw.
purpose a screw nut may either be applied to the threaded end of the fastener shank
which projects beyond the face of the scutcheon plate or this end of the fastener
shank is preferably provided with a crank handle as a means both of turning and
securing it, the tightening screw in that case working through a tapped hole in the
extremity of the crank and having its end received in a socket in the face of the
scutcheon plate, so as to both prevent the rotation of the fastener and draw its lug
or bit tight against the interior of the lock-casing. In this position it is impossible

page_text: to displace the device from the keyhole of to unlock the door either by its ovu or
a false key.
Dated this 5th day of September 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
improved Means of Preventing the Picking of Door-locks.
We, JOSEPH RICHARD PARKER, of 1, Beaconsfield Terrace, Church End
Willesden, London, N.W. Photographic Accessory Maker, and FRANK BISHOP
of the Firm of Marion and Co. of 22, and 23, Soho Square, London, W
Photographic Manufacturers, 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 relates to a device for preventing the picking of locks generally
but primarily intended for hotel bedroom doors for preventing the unlocking of the
door from the outside whilst the occupant of the chamber is asleep, either by
picking the lock or by turning the key supposing it to have been left in the lock.
The device may be said to consist of a keyhole stopper which is adapted to be
passed completely across the lock from front to back so as to effectually prevent
the key (should it have been left in the lock) being turned by any instrument
applied from the outside, and by stopping up the part of the keyhole which gives
passage to the key-bit prevent the introduction of a skeleton key or pick-lock
should the key have been withdrawn.
The invention is illustrated in the accompanying drawings, forming part of this
Specification, wherein
Figure 1 is a vertical section through a lock shewing the device in position,
Figure 2 is an elevation of the device viewed from that side of the door at which
it is applied, and
Figure 3 is a sectional elevation viewed from the opposite side.
Only the casing of the lock is shewn, the wards and other internal portions being
omitted for the sake of clearness.
The same reference letters denote like parts in all the figures.
The device, which is adapted to fold into a flat portable form such that it may
be conveniently carried in the waistcoat pocket, consists of a scutcheon plate A
adapted to cover the keyhole, (except that part which gives passage to the key-
shank b), and in this scutcheon plate is pivoted, at c, an arm D adapted to lie flat
with the plate A. when not in use or to stand out perpendicularly therefrom when it is
inserted in the keyhole, said arın then passing completely across the lock-case B,
its forward extremity terminating in an enlargement or bead d forming a stopper
for the keyhole next the outer side of the door, this head being of the pointed shape
shewn in Figure 1 to enable it to be readily passed through the keyhole and cause
any pick-lock that it may be attempted to insert, to be deflected without allowing it
to pass through the keyhole.
In order to secure the device in position, a key-shaped fastener is provided, the
shanke of which is free to turn and slide in a hole in the scutcheon plate A
immediately below the joint c of the arm D above described, and in order to admit
of the bit portion or lug E of this fastener passing through the keyhole along with
the arm D the latter is recessed or bevelled, as shewn in Figure 3, to receive the
bit E of the fastener which is correspondingly bevelled so that when turned upwards
it lies close alongside of and flush with or in the plane of the arm D so that in this
position the two can be passed together through the keyhole.
the fastener is thus passed, into the interior of the lock, the fastener is turned, say,
When the bit E of

page_text: a quarter round so as to bring its bit or lug out of register with the keyhole and
into position to engage with the wall of the lock-case B against which it is tightly
clamped by means of a tightening screw. For this purpose a screw nut may either
be applied to the threaded end of the fastener shank which projects beyond the
face of the scutcheon plate or this end of the fastener shank e is preferably provided
with a crank handle, as a means both of turning and securing it, the tightening
screw in that case working through a tapped-hole in the extremity of the crank and
having its end received in a socket f', in the face of the scutcheon plate A so as to
both prevent the rotation of the fastener and draw its lug or bit tight against the
interior of the lock-casing. In this position it is impossible to displace the device
from the keyhole or to unlock the door either by its own or a false key.
For the purpose of facilitating the application of the device and holding it
steadily in position until securely fastened, a pair of horn-like projections a, a, are
provided on the scutcheon plate A, forming upward continuations of the latter and
adapted to embrace the key-shank b.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The herein described device for preventing the picking of locks, consisting of
a scutcheon plate carrying a pivoted arm adapted to pass across the lock-case and
form a stopper for the key-hole on the outer side of the door, and a fastener for
securing the scutcheon plate in position on the inside of the door, substantially as
specified.
2. In a device for preventing the picking of locks constructed as described, the
means for securing the said device in position, consisting of the key-like fastener
and clamping screw, substantially as specified.
Dated this 29th day of October 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.