IMPROVE- MENTS IN LEVER LOCKS
Year: 1884

page_text: I, WILLIAM HENRY CHUBB of 349 High Street West Bromwich in the county
of Stafford Ironmonger do hereby declare the nature of my invention for IMPROVE-
MENTS IN LEVER LOCKS to be as follows:-
This invention consists in improvements in the construction of lever locks whereby
it is impossible to open or pick them without the proper key, and may be described
as follows:-
The chief novelty of my invention is the introduction of what I will call a master
lever. Upon this master lever all the other levers have their centre of motion, but
the centre of motion of the master lever, is at right angles or thereabouts, or, in
other words eccentric to the centre of motion of the other levers. The stud or pin
forming the centre of motion of the master lever, also serves as the guide for the
bolt.
My invention is applicable to lever locks of every description, and of any number
of levers, and with barrel and curtain arrangement.
When the bolt of the lock is shot, the master lever causes the teeth on the
ordinary lever rackings to be forced into a seration or groove upon the stump of the
bolt, which holds them fast, and prevents their being moved until the master lever
is lifted to its proper height.
When any pressure is applied to the bolt in order to move it back, or unlock it
by picking" or to "feel" the rackings of the levers, the master lever instantly
flies up and blocks the channel in the rackings of the levers and is held in that
position by a detector. This detector can only be removed by the right key, and
thus renders it impossible to withdraw the bolt or pick the lock.

page_text: I WILLIAM HENRY CHUBB of 349 High St West Bromwich in the county of
Stafford Ironmonger do hereby declare the nature of my invention for IMPROVE-
MENTS IN LEVER LOCKS 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 in improvements in the construction of lever locks, whereby
it is imposible to open or pick them without the proper key, and may be described
as follows. The chief novelty of my ihvention is the introduction of what I will
call, a master lever.
Upon this master lever all the other levers have their centre of motion but the
centre of motion of the master lever is at right angles or thereabouts, or in other
words excentric to the centre of motion of the other levers, The stud or pin
forming the centre of motion of the master lever, also serves for the guide for the
bolt. My invention is applicable to lever locks of every description and of any
number of levers, and with barrel and curtain arrangement.
When the bolt of the lock is shot, the 'master lever" causes the teeth on the
ordinary lever rackings to be forced into a seration or groove upon the stump of
the bolt, which holds them fast, and prevents their being moved until the master
lever is lifted to its proper height.
When any pressure, is applied to the bolt in order to move it back, or unlock it
by "picking," or to feel the rackings of the levers, the master lever instantly flies
up and blocks the channel in the rackings of the levers, and is held in that position
by a detector. This detecter can only be removed by the right key and thus
renders it imposible to withdraw the bolt or pick the lock.
I will now proceed to describe with reference to the accompanying drawings the
manner in which my invention is to be used.
Figure 1 is a plan showing the frame of lock with the bolt in a locked position.
Figure 2 is a plan showing the frame of lock with bolt in a locked position, the
master lever also placed in its ordinary position.
Figure 3 is a plan showing the frame of lock with the bolt B in a locked position,
the master lever J in its defensive position and one ordinary lever K placed in its
normal position on the bolt.
Figure 4 is a plan showing the frame of lock with the bolt in a locked position
the master lever together with the whole of the ordinary levers also in their
normal position ready for use.
Figure 5 is a detail plan of master lever.
Figure 6 is an edge view of figure 5.
Figure 7 is a detail plan of ordinary lever.
Figure 8 is a section of Figure 2 at W X.
Figure 9 is a section of figure 4 at Y Z
In carrying out my invention I provide a suitable frame also a bolt on which to
fix the master lever that constitutes the chief novelty of my invention

page_text: F Figures 1-2-3-4 is the stud or pin forming a guide for the slot C the vertical
height of this stud terminates with the upper face of the bolt B.
& Figures 1-2-3-4 is the stud or pin forming a guide for the slot D, the vertical
height of this stud is extended past the face of bolt D to form the centre of motion
of the master lever.
H Figures 1-2-3-4-8-9 is the stop stud to receive the ends of lever springs L
J Figures 2-3-8-9 is the 'master lever."
K Figures 3-4-9 and K¹ K* K* K* K³ Figure 9 are the ordinary levers.
L Figures 2-8-9 is the master-lever-spring. L L L L L Fig 9 are the ordinary
lever springs. M Figures 2-3-4-5-6-8 is the stud or pin secured to the master
lever and forming the centre of motion or pivot pin of levers K K' K³ K³ K' K³.
N Figure 5 represents the pivot hole provided in master lever to work on stud G.
O Figure 7 represents the pivot hole provided in levers K K' K' K³ K* K* to
work on pivot M.
A suitable frame and bolt being provided as represented at Figure 1 I take my
master lever as represented at Figure 5 and pass the pivot hole N over the stud G
as represented at Figure 2 I then take one of the ordinary levers as represented
at Figure 7 and pass the pivot hole O over the stud M of master lever as represented
at Figure 3.
It will be now apparent that any pressure exerted against the bolt B by the
finger P in the direction of the arrow Q would move the master lever J into the
defensive position clearly shown at figure 3, thus effectually blocking the channels
or passages in the ordinary levers.
Of course pressure exerted by means of wires; picks or other contrivances
against the bolt, so long as it was exerted in the direction of the arrow Q would
produce the effect on the master lever represented at Figure 3.
I do not confine myself to the particular pattern of fram A or to any specified
number of levers as I can use the bolt, master-lever and ordinary levers in frames
suitable for various classes of locks.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that what
I claim is
The making of locks in the manner illustrated and described at Figures 2-3-4-
5-6-7-8-9 that is to say the making of locks with a master-lever working on
a centre of motion excentric with the centre of motion of the ordinary levers
the ordinary levers working on a centre of motion formed on and constituting part
of the master lever, so that any pressure exerted against the bolt to unlock it when
locked other than that exerted by the proper key will cause the master-lever to rise
up in its defensive position and block the channels in the rackings of the remaining
levers.
AN
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