IMPROVEMENTS IN Locks
Year: 1852

page_text: LETTERS PATENT to John Chubb, of St. Paul's Church Yard, in
the City of London, for the Invention of "IMPROVEMENTS IN
Locks,"
Sealed the 17th January 1858, and dated the 1st November 1852.
PROVISIONAL SPECIFICATION left by the said John Chubb at
the Office of the Commissioners of Patents, with his Petition, on
the 1st November 1852.
I, JOHN CHUBB, of St. Paul's Church Yard, in the City of London,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN LOCKS" to be as follows:-
These improvements consist of arranging the tumblers and apparatus
in order to prevent the lock being acted.on, by putting pressure on the
bolt and feeling the tumblers separately. The pressure causes the bolt
and the tumbler to be locked into the stump, which is made with inter-
locking parts corresponding with like parts in the tumblers.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Chubb in the Great Seal Patent Office
on the 30th April 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOHN CHUBB, of Saint Paul's Church Yard, in the City of London,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of November, in the
year of our Lord One thousand eight hundred and fifty-two, in the
sixteenth year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said John Chubb, Her special
licence that I, the said John Chubb, my executors, administrators,
and assigns, or such others as I, the said John Chubb, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
Locks," upon the condition (amongst others) that I, the said John
Chubb, by an instrument in writing under my hand and seal, should
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Chubb, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof (that is to say):
These improvements consist of arranging the tumblers and apparatus
in order to prevent the lock being acted on, by putting pressure on the
bolt and feeling the tumblers separately. The pressure causes the bolt
and the tumbler to be locked into the stump, which is made with inter-
locking parts corresponding with like parts in the tumblers. And in
order tha my Invention may be more fully understood T will proceed
to describe the Drawings hereunto annexed.

page_text: Sheet 1, shows several views of a lock having my improvements
applied thereto.
Sheet 2, shows similar views of another lock constructed according
to my Invention.
The object of these improvements is, with a view to render the picking
of a lock made according thereto impossible.
. To enable me to describe the mode of action of the several parts, I
will first mention that in order to pick locks having tumblers it has.
been the practice of skilful persons to press back the bolt in such
manner that when the tumblers are severally raised by the picklock or
instrument used, the parts of the tumblers so raised shall permit the
stump on the bolt to enter and pass through the spaces of the tumblers,
and thus, by continuing the pressure on the bolt until all of the
tumblers shall have been moved sufficiently, the bolt may be allowed
to pass. Now with my improvements this mode of picking the: lock
is frustrated, for should the tumblers be raised by any instrument other
than a proper key, a spring catch, hereafter described, descends imme-
diately on the partial sliding back of the bolt, and enters and locks into
a recess formed in the bolt, and the tumblers also lock into the stamp
on the bolt.
Figure 1, shows the bolt as thrown forward or locked; Figure 2,
shows the same with the tumblers raised by a picklock or other instru-
ment during pressure on the bolt a; and Figure 3, shows the position
the parts assume if an attempt is made to pick the lock. a, is the bolt,
which differs only from those now in use by its having the recess a',
formed in it. The stump a², of the bolt a, I form with a recess a³, as
shown, the sides of such recess a³, acting as teeth to enter the false
notches b', 6', of the tumblers b, b, as is shewn in Figure 3. c, is a
spring, having at one end a catch c', which enters the recess a¹, of the
bolt a, in the event of any attempt being made to pick the lock by
pressing back the bolt. When moving the bolt a, backwards or for-
wards by a suitable key, the spring catch c', is prevented from descend-
ing into the recess a', by the projecting parts 6, on the upper sides of
the tumblers b.
In Sheet 2, of the Drawings another form of lock is shewn, similar

page_text: in its principle of action, but in addition to the improvements already
described the bolt a, has a recess a', a', above and below the ordinary
slot formed to receive the stamp a", on to which the tumblers are placed.
The purpose of these additional recesses in the bolt a, is, that when an
attempt is made to pick the lock, the pressure back of the bolt would
cause the bolt to move a little so as to cause the square portion of the
pin or stump a³, to enter one of the recesses at, a', and thus offer an
additional security against any attempt made to pick the lock by
forcing back the bolt and acting on the tumblers in succession.
Having thus described the nature of my Invention, and the manner
of performing the same, I would have it understood that I do not confine
myself to the details, as the forms of the parts may be varied without
departing from my Invention; but what I claim is, the combining of
the parts of locks as herein described.
In witness whereof, I, the said John Chubb, have hereunto set
my hand and seal, this Thirtieth day of April, in the year of
our Lord One thousand eight hundred and fifty-three.
Witness,
FRED HARRIS.
JOHN CHUBB. (L.S.)