IMPROVELIENTS IN THE CONSTRUCTION AND ARRANGEMENT OF LOCKS." IN THE CONSTRUCTION AND EMENT OF
Year: 1855

page_text: LETTERS PATENT to Constantine Henderson, of Tufnell Park, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVELIENTS
IN THE CONSTRUCTION AND ARRANGEMENT OF LOCKS."
IN THE CONSTRUCTION AND ARRANGEMENT OF LOCKS."
Sealed the 9th November 1855, and dated the 11th May 1855.
PROVISIONAL SPECIFICATION left by the said Constantine Henderson
at the Office of the Commissioners of Patents, with his Petition, on
the 11th May 1855.
I, CONSTANTINE HENDERSON, of Tufnell Park, in the County of Middlesex,
Gentleman, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION AND ARRANGEMENT OP Locks" to be as follows:-
This Invention relates to a peculiar construction and arrangement of certain
parts of locks, whereby they are rendered less liable to be opened with a pick or
false key than any of the locks at present in use. The improvements consist in
adapting to the outside of the face plate a species of auxiliary lock, which
requires to be first opened before the keyhole of the main lock can be entered
by the key. This auxiliary lock is composed of a number of concentric wards
and concentric split rings, which work round the pipe of the lock in the spaces
between the concentric wards. The whole is covered by a shield and outside
casing, so that when the key is out the keyhole is perfectly closed. An addi-.
tional ward is fitted inside the main lock round the pipe, a sufficient amount of
space only being allowed between the outside of the pipe and the inside of the

page_text: ward equal to the thickness of the metal of the pipe of the key. In opening
this lock by the proper key, the key is first inserted into the auxiliary lock in a
reversed position to that which it must assume before it can enter the main
lock, the keyhole of which is suitably situated, and entirely concealed by the
concentric rings before mentioned. The splits in each of these rings are all
brought round to correspond to the main keyhole by turning the key, where-
upon the key is at liberty to enter the main lock, and having entered therein
all the concentric rings will be held fixed by a suitable catch until the key is
withdrawn again, whereupon, on the key coming in contact with the holding
catch, the rings will be released again, and free to turn round with the key
before its withdrawal from the auxiliary lock. The internal concentric ward
serves to prevent the possibility of acting upon the main bolt for the purpose of
shooting it whilst the tumblers are held up to the required elevation by other
implements.
SPECIFICATION in pursuance of the conditions of tho Letters Patent, filed
by the said Constantine Henderson in the Great Seal Patent Office on
the 10th November 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CONSTANTINE
HENDERSON, of Tufnell Park, in the County of Middlesex, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of May, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Constantine Henderson, Her special license that I, the said
Constantine Henderson, my executors, administrators, and assigns, or such
others as I, the said Constantine Henderson, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term thercin 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 IMPROVEMENT: IN THE CONSTRUCTION AND ARRANG"
upon the condition (amongst others) that I, the said Constantine Henderson,
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
"

page_text: 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 Constantine Henderson, do hereby
declare the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings, and
to the letters and figures marked thereon, that is to say :-
My said Invention relates to certain peculiar constructions and arrangements
of and additions to certain parts of locks, whereby they are rendered less liable
to be opened with a pick or falso key than any of the locks at present in use.
The improvements consist in adapting to the outside of the face plate of any of
the well-known locks a species of auxiliary lock, which requires to be first
opened before the keyhole of the main lock can be entered by the key. This
auxilliary lock consists of one or more concentric split rings, which work
round the pin of the lock in the spaces between the concentric wards.
The whole is covered by a shield and cutside casing, so that when the key is
out the keyhole of the main lock is perfectly closed. An additional ward may
be fitted inside the main lock round the pin, a sufficient amount of space only
being allowed between the outside of the pin and the inside of the ward equal
to the thickness of metal of the pipe of the key. In opening this lock by the
proper key, the key is first inserted into the auxiliary lock in a reversed position
to that which it must assume before it can enter the main lock, the keyhole of
which is suitably situated, and entirely concealed by the concentric ring or rings.
before mentioned. The splits in each of these rings are all brought round to
correspond to the main keyhole by turning the key, whereupon the key is at
liberty to enter the main lock, and having entered therein all the concentric rings
will be held fixed by a suitable catch or spring until the key is withdrawn again.
One or more catches or springs may also be so arranged as to hold the rings
fixed until the key on coming in contact with such catch or catches will release
the rings, which will be again free to turn round with the key preparatory to
its final withdrawal from the auxiliary lock. The internal concentric ward in
the main lock serves to prevent the possibility of acting upon the main bolt
for the purpose of shooting it whilst the tumblers are held up to the
required elevation by other implements.
And in order that the said Invention may be fully understood, I shall now
proceed particularly to describe the same, and for that purpose I shall refer to
the several Figures on the Sheets of Drawings hereunto annexed, the saine
letters of reference indicating corresponding parts throughout all the Figures
on each Sheet of Drawings.

page_text: Figure on Sheet 1 of my Drawings represents a front elevation of an
ordinary lock with the auxiliary lock attached thereto; Figure 2 is a corre-
sponding side elevation of the same; Figure 3 is a front elevation of the two
locks with the second or outer cap of the auxiliary lock removed; Figure 4 is
a corresponding side elevation of the same, with the outer cap, shewn in section,
fitted into its place; Figure 5 is a detail plan of tho interior of the e cap, shewing
tho spring for steadying the concentric rings; Figure 6 represents a front or
face elevation of the main lock, shewing the position of the wards and concentric
split rings of the auxiliary lock; Figure 7 is a side elevation of the same,
having the first or inner cap removed to shew the interior of the auxiliary lock,
which is shewn in section; and Figure 8 is a detail sectional elevation of the
first or inner cap detached. The rest of the Figures on this Sheet are details,
which will be herein-after more fully described and referred to. A is an ordinary
lock, with any of the well-known improvements adapted thereto, the internal
arrangement of which need not be interfered with in adapting the auxiliary
protector B thereto. The position of the keyhole of the auxiliary protector
lock is exactly the reverse of that of the main lock A, so that the key, on being
entered, must be turned half way round before it can enter the keyhole of the
main lock. The internal arrangement of the auxiliary lock consists of two or
more concentric split rings C, C, which rings are represented in detail plan and
section at Figures 9 and 10. These rings are fitted concentrically to the pin D
of the main lock, and are free to turn round the fixed concentric wards E, E,
(Figure 6), in which Figure the rings are shewn in their proper places. The
split portion F of the rings coincides with the keyhole of the auxiliary lock
when the key is removed, but on the key being inserted and turned half way
round, the rings C are carried round with it until the key coincides with the
keyhole of the main lock, into which it may then be inserted. This turning of
the concentric rings effectually debars all means of entrance to the auxiliary
lock during the time the key is inside. Small studs or stops G, G, are made
on each ring, and these stops work in the semicircular slots H, II, in the inner
cap (Figure 8). A flat metal spring J, fitted inside the outer cap K, shewn
more clearly at Figure 5, presses upon the studs or stops G, and serves to
prevent the rings from being easily pushed or shaken out of position. Figure
11 represents a side elevation of a key which would open the auxiliary lock
only, the impression which would be obtained therefrom being shewn by the
two slots L, L, on the key. As this key, however, would not open the main
lock, it would be found perfectly useless, whilst at the same time the fact of its
being inside the auxiliary lock would effectually debar all further entrance into
or tampering with the main lock. The true key, which would open both the

page_text: auxiliary and the main lock, is represented in side elevation at Figure 12. It
will thus be obvious, that although an impression may be taken of the wards
in the auxiliary lock, yet a key made from such impression would be found
perfectly useless when applied to the main lock, as will be obvious on com-
paring the two keys. I may here observe, that although I have described and
illustrated an auxiliary lock composed of two concentric split rings, I wish it
to be distinctly understood that I do not confine or restrict myself to that
precise number of rings, as a greater number might of course be used with
a like result, or one single split ring only might be employed in place of two
rings, suitable springs or catches being added, for the purpose of fixing the
ring or rings, and affording increased security to the lock.
Figure 1, on Sheet 2 of my Drawings, represents a front elevation of an
auxiliary lock, modified in the manner I have herein-before last described, fitted
to an ordinary lock face plate, one-half of the cap or shield being removed to
show the single ring inside. Figure 2 is a similar view, with the auxiliary lock
removed, to show the arrangement of the wards therein, and the spring catch
for fixing the ring. Figure 3 is an edge view of the main lock, with the
auxiliary lock in vertical section; and Figure 4 is a detail plan of the under
side of the single ring in the auxiliary lock, shewing the position of the
inclined notches for the spring catch, herein-after fully described and referred
to. A is the face plate of the main lock, which may be of any of the well-
known constructions. On to this face plate are fitted the two concentric wards
B, B', the ward B fitting accurately inside the circular portion of the key-slit C,
in the solid ring D, whilst the outer ward B' fits into the ring groove E, in the
said ring. This ring, on being fitted on to the wards above referred to, is
covered over by the cap or shield F, which is screwed on to the face plate of
the main lock. The keyhole formed in this cap or shield is formed in exactly
the reverse position to the keyhole of the main lock, and coincides accurately
with the slit C of the ring D, when the key is out of the lock. A spring catch
G is secured at one end on to the face plate of the main lock, whilst its free
end takes into the inclined notch H, in which position the slit C of the ring D
will exactly coincide with the keyhole of the auxiliary lock, and by the action
of this spring catch the ring D will be prevented from turning in any other
than the direction shewn by the arrows, which is the proper direction for
turning the key after it is inserted into the auxiliary lock. A second inclined
notch His also formed in the under face of the ring D, the object of which is
to fix the ring, after allowing it to turn a short distance, or until tho false key
comes in contact with the end of the outer ward B³, in cases where an attempt
is made to obtain an impression of the ward or wards in the auxiliary lock, or

page_text: when a false key is inserted. The ring D being thus effectually prevented from
turning back again by the engagement of the spring catch G with the second
notch H, the false key will be held fixed inside of the lock, without any
possibility of its removal until the lock is taken off the door; for although
the ring D is. always free to turn in the direction of the arrows, it will not
turn back again, being prevented by the spring catcb, and it cannot be turned
forwards on account of the key striking against the end or ends of the ward
or wards B¹, one of which only is shewn in the Drawing, although any number
may be used. In using the true key, the ring D is first turned half way
round in the direction of the arrow, when the key will coincide with the
keyhole of the main lock, and after having acted upon the bolt thereof the
key is withdrawn into the auxiliary lock, and the entire revolution of the ring
is completed, in order to admit of the removal of the key from such lock.
One or more of the spring catches herein-before referred to may obviously
be applied to the first-described arrangement of auxiliary lock, when a number
of concentric rings are used, in which case tho rings will have to make an
entire revolution, as in the last-described arrangement, in place of only half a
revolution, and then back again in the contrary direction, to withdraw the key,
as in the first lock.
Figure 5 on Sheet 2 of my Drawings represents a side elevation of a modifi-
cation of the second arrangement of auxiliary lock, having one ring only, the
spring catches of which are slightly modified; Figure 6 is an end elevation of
the main lock, shewing the auxiliary lock in vertical section; Figure 7 is a
view of the face plate of the main lock, with the single ring of the auxiliary lock
removed, to show the internal wards thereof, and the arrangement of spring
catches; and Figures 8 and 9 represent respectively an under side plan and cor-
responding section of the single ring of the auxiliary lock detached. The mode
of working this lock is precisely similar to that of the single ring lock herein-
before described; that is, the ring A can only turn in one direction, and must
consequently make an entire revolution in the direction of the arrow, after the
key has been inserted, before it can be withdrawn again. A number of ratchet
teeth are formed round the periphery of the ring A, into which teeth are
engaged the palls or detents B. which are acted upon by the blade springs C.
A spring catch D is rivetted inside the auxiliary lock, and works through the
notches E, E, in the lower edge of the keyhole in the ring A, the object of
which catch I shall herein-after describe. F, F, are two concentric wards
placed inside the auxiliary lock. These wards are sufficiently high to com-
pletely protect the spring catch D from being tampered with, and they work
through the notches E, E, and G, G, in the ring A. A slight projection on

page_text: the face plate of the main lock is formed at H, to act as a slight resistance to
the key, so that the party turning the key will readily feel when it coincides
with the keyhole of the auxiliary lock, and may then withdraw it accordingly.
A notch is made also at I in the periphery, or in any other suitable part of the
ring, for the same purpose, a blade spring J being made to take into it. K. is
another notch, for the purpose of feeling when the key coincides with the key-
hole of the main lock.
In attempting to open this lock by means of a false key, or endeavouring
to obtain an impression of the wards in the auxiliary lock, the ring A must be
turned partly round, so as to bring the key against the wards F, F. The key
will then move no further, and it cannot be turned back again on account of
the detents and ratchets. Supposing, however, that a skeleton key be intro-
duced, so as to pass over the tops of the wards F, F, the ring A will then turn
round until one of the notches E, E, is brought against the angular end of
the spring catch D, as shewn by the dotted lines in Figure 8. In this case
the ring cannot be turned any further forwards, as the spring catch D will
effectually prevent it, and it cannot be turned back again by reason of the
ratchet and detents, so that in either case the false or skeleton key will be held
firmly fixed in the lock, and will itself form a most effectual barrier against all
further tampering with the same. When the true key is inserted, it will pass
the wards F, F, and on arriving at the spring catch D it will depress the
same, and allow the notches E, E, in the ring to pass clear of the spring catch.
The key having been inserted into the main lock, and having acted upon the
bolt, is withdrawn into the auxiliary lock again, and completes the second half
of the revolution of the ring A, preparatory to its final withdrawal from the
auxiliary lock. The projecting ring L fixed on the face plate of the main
lock serves as a guide for the ring A to turn upon, a corresponding ring groove
being made in the ring to receive such annular guide. A shield or cap M,
shewn in section in Figures 5 and 6, is secured to the main lock, and encloses
and conceals the entire mechanism of the auxiliary lock, the ring A of which
entirely closes the keyhole of the shield when tho ring is partially turned.
Having now-described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe, in conclusion, that I do not confine or restrict myself
to the precise details or arrangements which I have had occasion to describe or
refer to, as many variations may be made therefrom without deviating from
the principles or main features of my said Invention; but what I consider to
bo novel and original, and therefore claim as the Invention secured to me by
the herein-before in part recited Letters Patent, is,-

page_text: First, the general constructions and arrangements of auxiliary protector
locks, as herein-before described.
Second, the application of an auxiliary protector lock to the face plate of
any ordinary lock, such auxiliary protector lock consisting of suitable wards,
and one or more concentric rings or discs, acted upon by suitable catches or
holding springs, in the manner and for the purpose herein-before described.
Third, the application and use of a circular ward concentric to the pin of
the main lock, and fitted inside such main lock in such a manner that there
shall only be sufficient space between the pin and the ward to receive the
thickness of metal of the pipe of the key, whereby the bolt is protected from
the action of picks so long as a key is in the lock.
In witness whereof, I, the said Constantine Henderson, have hereunto set
my hand and seal, the Fifth day of November, One thousand eight
hundred and fifty-five.
CONSTANTINE HENDERSON. (LS.)