CERTAIN IMPROVEMENTS IN LOCKS AND LATCHES TO BE USED FOR FASTENINGS
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
CHUBB, of Saint Paul's Church Yard, in the City of London, Patent Lock
and Fireproof Safe Manufacturer, send greeting.
WHEREAS I did, by Petition, humbly represent unto Her most Excellent
Majesty Queen Victoria that I had invented "CERTAIN IMPROVEMENTS IN LOCKS
AND LATCHES TO BE USED FOR FASTENINGS;" and Her said Majesty, being willing
to give encouragement in all arts and inventions that may be for the public
good, was graciously pleased, by Her Royal Letters Patent under the Great
Seal of the United Kingdom of Great Britain and Ireland, bearing date at West-
minster, the Fourteenth day of December (One thousand eight hundred and
forty-six), in the tenth year of Her reign, for Herself, Her heirs and successors,
to give and grant unto me, the said John Chubb, my executors, administrators,
and assigns, Her especial licence, full power, sole privilege and authority. that I
or they, by myself or themselves, or by my or their deputies, servants, or
agents, or such others as I or they shall agree with, and no others, during
the term of fourteen years from the date of the said Letters Patent, should
and lawfully might make, use, exercise, and vend my said Invention,. within
that part of Her said Majesty's Dominions called England, Her Dominion of
Wales, and Town of Berwick-upon-Tweed, and the Islands of Jersey,
Guernsey, Alderney, Sark, and Man, and also in all Her Majesty's Colonies

page_text: and Plantations abroad, in such manner as to me, my executors, administrators,
and assigns, shall seem meet, and as that I or they shall enjoy the whole profit
and advantage arising by reason of the said Invention during the said term of
fourteen years; and whereas the said Letters Patent contain a proviso, obliging
me, the said John Chubb, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, by an
instrument in writing under my hand and seal, and to cause the same to be
enrolled in Her Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters Patent,
as in and by the same (reference being thereunto had) will more fully and at
large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Chubb, do hereby declare that my said Invention is described and
ascertained in manner following, and by the aid of the two Sheets of Drawings
hereunto annexed (that is to say) :-
The object of my said improvements in locks and latches to be used as
fastenings is, to obtain the utmost possible security against the opening of
locks or latches which ar constructed according to my said improvements,
either by means of any kind of picklocks or of false keys; and that object I
attain by application in the manner herein-after described of a greater number
of the parts called tumblers than have been heretofore applied in locks, or
than could be applied with advantage according to the ordinary mode of
applying tumblers to the sliding bolt or bolts of the lock. According to my
improvements the whole number of the tumblers which are to operate together
in the same lock or latch are arranged in two, three, or four distinct sets
arranged round the centre pin or centre of motion of the key, so as that the
whole number of the said tumblers will be lifted simultaneously by action of
one key, which has as many different bits as the number of distinct sets afore-
said, in which the whole number of tumblers are arranged, those different bits
projecting out from the central part of the key on different sides of that central
part suitably for the different positions in which the aforesaid distinct sets of
tumblers are arranged around the centre of motion of the key, in order that
each one of the said bits of the key may act upon the several tumblers of one
of the said sets of tumblers, so as to move or lift each of those tumblers to
its proper intended position (with the usual action of the lifting of the several
tumblers of one set by the one bit of the key in ordinary tumbler locks), but all
the two, three, or four bits that the key may have will act simultaneously on so
lifting the tumblers of the two, three, or four distinct sets in which the whole

page_text: number of tumblers may be arranged, wherefore all the tumblers constituting
that whole number of tumblers will be lifted to their respective intended
positions at one and the same moment by one action of turning the key; for
although the different bits of the key act distinctly one from the other (each
bit acting to lift the several tumbler of that set to which the said bits applies)
the distinct actions of the several bits are simultaneous. And further, the stud
or stump pin which acts in the notches of the tumblers of each set of tumblers
is not fastened into the bolt of the lock, as usual in ordinary tumbler locks, but
instead thereof the two, three, or four stump pins belonging to the two, three,
or four sets of tumblers are all fastened into a flat circular plate, which is
moveable round the centre pin or centre of motion for the key; the several
stumps being arranged at such places in the said circular plate as to correspond
to the several sets of tumblers wherewith each stump is to act respectively,
and the motion of the said stumps (after all the tumblers have been lifted by
action of the key, so as to permit the stumps to move), will take place in
circular arches about the said centre of motion, because all the stumps being
fastened into the said circular plate, they will all be carried round together by
motion thereof around its said centre of motion. And the sliding bolt of the
lock is connected with the said circular plate by a pin projecting from the
plate and entering into a transverse notch in the bolt (or vice versa) so that
the endway motion or shooting of the bolt will of necessity be accompanied
with a small extent of turning motion of the circular plate about the said
centre of motion. But all such endway motion of the sliding bolt and turning
motion of the circular plate is effectually prevented by the aforesaid stumps
being interlocked in the notches of the tumblers, except when every one of
those tumblers has been lifted by action of the bits of the key into the proper
intended position for each of the tumblers respectively, so as to bring all the
notches of the tumblers of each set into correspondance one notch with
another, and with the stump belonging to that set, which being done with
all the tumblers simultaneously, then none of the tumblers will offer any.
impediment to the motion of the stumps, but they and the circular plato
in which they are fastened, and also the sliding bolt, will be at liberty to
be moved by the usual action of one of the bits of the key against what
is called the talon of the bolt, or, in the case of a latch, such motion may be.
communicated to the bolt by reaction of a suitable spring for shooting the
bolt, although the motion for withdrawing or unlocking the same bolt must be
given by the aforesaid action of one of the bits of the key against the said talon
of the bolt. And for the more complete explanation of the manner of applying

page_text: and using my said improvements advantageously, in concert with other ordi-
nary and well-known parts of locks, I have in the annexed Drawings given
full size representations of a very complete and most secure lock, constructed
according to my said improvements, with four sets of tumblers and four bits
on the key, also four stumps in the circular plate aforesaid, to act in the
notches of the four sets of tumblers, the whole number of which tumblers is
nineteen in the four sets. And further, each set of tumblers is provided with
a detector, constructed and applied to those tumblers according to improve-
ments formerly invented by my late father Charles Chubb, and for which
Letters Patent were granted to him and to Ebenezer Hunter, the said
detectors having the effect of coming into action of themselves for preventing
the lock from being unlocked (even by its own key) in case of any one of the
tumblers of either of the four sets having been lifted too high in attempts to
'unlock the lock by introduction of picklocks or false key. The lock in such case
becomes more difficult to unlock in consequence of the action of the detector,
and the lock also shews that such attempts have been made by the circum-
stance that it cannot be afterwards unlocked by its own proper key until
a suitable manipulation has first been made with that key for undetecting the
lock, and putting the detector or detectors out of action. And further, the
said lock is provided with an escutcheon lock, the sliding bolt of which, when
locked, shoots its end across the aperture of the keyhole of the principal lock
so as to shut up the hole, in order to prevent the introduction of any picklock
or false key, or the true key at the keyhole, unless the said sliding bolt of the
escutcheon lock is first withdrawn, which would be exceedingly difficult to do
without the true key of that escutcheon lock, for the said sliding bolt thereof
has a complete set of tumblers with a detector thereto, in the manner of the
safest locks heretofore made. Also the said bolt is made of steel so hardened
and tempered at the part which shuts up the keyhole that it cannot be cut or
drilled. The said lock is represented as being applied to secure and fasten a
combination of four door bolts which actually fasten the door to which the lock
is applied by shooting out in four directions, so as to bolt the door at its top
and its bottom, and at each of its sides. Those four bolts are not moved by
the lock or its four-bitted key, but are moved by a handle at the outside of the
door, together with a circular turning wheel inside the door, connected with
the handle, and having four spiral grooves in that wheel which act to shoot all
the four bolts at once, when the handle and wheel are turned so as to fasten
the door by the said four bolts, and then the sliding bolt of the lock being
shot by its key with four bitts locks into a notch in the said turning wheel, and

page_text: thereby acts to prevent the said four bolts from being withdrawn by means of
the said turning handle, even although the same should remain accessible at
the outside of the door, because the turning wheel at the inside of the door
is fastened by the bolt of the lock, and prevented from being turned. And in
case of a latch instead of a lock being constructed according to my said.
improvements, then all the aforesaid parts, and the said sliding bolt herein-
before mentioned as the sliding bolt of the lock, may be nearly the same,
except as to being a spring or latch bolt, that is, having a spring applied to it,
and exerting a constant tendency to urge the bolt forwards endways, so as to
latch of itself by entering into the said notch in the aforesaid turning wheel,
so soon as the said notch is brought (by the turning round of the said wheel)
opposite to the end of the said spring sliding bolt of the latch. Wherefore
the latch will fasten of itself after the door is shut and has been bolted by its
four fastening bolts, without any application of the four-bitted key for so
fastening; but the application of that koy is necessary for withdrawing the
spring sliding belt with the same aaction, as already explained, out of the
said notch in the turning wheel, in order to have the same at liberty to be
turned round by means of its handle for unbolting all the four fastening bolts
of the door. The spring bolt when so withdrawn from the said notch will
remain on the latch ready to latch again by reaction of its spring as before,
whenever the four door bolts are bolted again.
Fig. 1, Sheet I., represents the lock in elevation as it stands behind the
door, with its cover plate removed to shew the interior parts, which are all in
their places complete. Fig. 2 is a vertical cross section through the centre of
motion of the key. Fig. 3 is a horizontal section through the said centre of
motion., Fig. 4 is another vertical cross section through the centre of motion
of the circular turning wheel for shooting the four door bolts all at once.
Fig. 5 is another horizontal section through the centre of motion of the key
for the escutcheon lock as the section would appear when viewed from below
upwards.
Fig. 6, Sheet II., is an elevation corresponding to Fig. 1, except that the
parts nearest to the spectator in Fig. 1 are removed in Fig. 6 in order to
exhibit other parts which are more remote and are concealed in Fig. 1. The
remaining Figures in Sheet II. are detached parts shewn separately. The
same letters of reference denote the same parts in all the Figures. A is the
rim or exterior case of the lock, consisting of a bottom or back plate C
and four sides A, as usual in other locks. B, Figs. 2, 3, 4, 5, is the cover
plate (in section) which fits to the said four sides A, and is fastened thereto in

page_text: place with screws so as to form a complete box or case which encloses all the
mechanism of the lock. The said cover plate B applies against the inside of
the door when the lock is fastened by screws in its place against that inside.
The keyhole is cut out through the cover plate B suitably for the admission of
the key with four bits, the keyhole being in the form of a cross, thus x; and
a corresponding keyhole is cut through the door. Note, the cover plate B is
fortified by a plate of steel, hardened and tempered, fastened to the outside of
the cover plate, as shewn at b, b, Figs. 2, 3, 5, in order to prevent any cutting
or drilling into the lock, even if the door itself should have been cut or
drilled through. The said steel plate b, b, applies against the inside of the
door when the lock is in place, and the keyhole is formed in that steel
plate which prevents enlargement of the keyhole. a is the fixed centre pin,
on which the tube or pipe of the key fits, and which pin serves as its centre of
motion. D, E, F, G, are the four sets of tumblers, which are arranged at
'equal distances apart around the central pin a, and at equal distances from that
pin. h, h, h, h, are the four fixed centre pins, about which the tumblers of
each set are moveable, and 1, 1, 1, 1, are the sets of springs by which the several
tumblers of each set are continually urged to move about their respective centre
pins in a direction towards the centre pin a. There are five tumblers in each
set, all mounted on the same centre pin h, the five being one behind another;
wherefore they conceal one another in Fig. 1, but are distinguishable in the
sections Figs. 2 and 3. Each of the sets of springs 1 is formed of one piece of
steel cut with nicks like the teeth of a comb, so as to become divided into five
springs which act independantly oue of another, but one spring acts behind
each tumbler of the set of tumblers to which the set of springs belongs. See
Fig. b, Sheet II., which represents one of the sets of springs detached. His
the flat circular plate which is fitted on the centre pin a, so as to be moveable
thereon for its centre of motion. The plate H is situated behind all the four
sets of tumblers D, E, F, G, and the stumps m, n, o, p, which are firmly fastened
into the plate H, project out from it at right angles to its plane, so as to pass
through the notches of all the tumblers of each set in order to be interlocked
in those notches, as is shewn in Fig. 1, and in the sections Figs. 2 and 3, where
the plate II, and its stumps m, n, o, p, are distinguished by being of the same
color as the same parts in Fig. 1. The plate H appears more distinctly in
Fig. 6, Sheet II., because the tumblers are all removed. Fig. H, Sheet II.,
shews the plate H detached, and Figure D, E, F, G, the four sets of tumblers
detached, but with their respective sets of springs in their relative positions.
I-is the sliding bolt of the lock situated behind the circular plate H, between

page_text: that and the back plate C of the lock, as appears in the sections Figures 2
and 3. See also Fig. 6 and Figure I. Sheet II., the latter shewing the bolt
detached. The centre pin a projects out from the middle on a flat rectangular
plate, which is fastened behind the back plate C of the lock by screws, the
pin a passing through the plate C, and standing forwards as a firmly fixed
centre pin in the space between the four sets of tumblers. The pin a also
passes through a slot in the bolt I, and through the central hole of the circular
plate H. The four centre pins h, h, h, h, for the tumblers are fixed into the
back plate c of the lock, and stand forward therefrom. The pins h, h, for two
sets of tumblers D and F, pass freely through slots in the bolt I, and by means
of a stud pin and slot x in the tail end of the bolt, that end is guided in its
endway motion, the other, or locking end of the bolt, being guided by passing
through the piece J, which is firmly fastened to the back plate C of the lock;
or, in case of a smaller sized lock, then J might be straight, and form part of
the rim A or exterior case of the lock, with the locking end of the bolt I
shooting out through the rim A in the usual manner of ordinary locks.
9, Fig. 2, is a pin projecting out behind the circular plate E, and entering into
a transverse slot y, Fig. I., Sheet II., in the bolt I, so as to cause the bolt I and
the circular plate II to move together, and also to prevent either one moving
without the other, but each will move with its own kind of motion, videlicet,
the bolt I sliding endways through its proper extent of such motion for locking
and unlocking, will require the plate H to turn round about its centre pin a
with a small extent of circular motion; but the stumps m, n, o, or p will prevent
the latter motion by their interlocking into the notches. of the tumblers, unless
all the tumbers in all the four sets D, E, F, G, are lifted or moved (by action
of the several stops on the four bits of the key against the edges of the several
tumblers respectively), so that all the notches in the tumblers of each set will
come into exact correspondence one notch with another, and all the notches in
exact correspondence with that stump m, n, o, or p, which acts in those notches,
and after the whole number of tumblers in all the four sets have been so
lifted exactly to the proper intended position for each tumbler, then the
notches of the tumblers will allow the stumps m, n, o, p, to move freely with
the circular motion due to the flat circular plate H, from which those stumps
project out. But if any one or more tumblers out of the whole set is not
lifted high enough (that is to say, not moved far enough away from the centre
pin a), or if any one or more of the tumblers is over lifted (that is to say,
moved too far away from the said centre pin a), that one or more tumblers
will detain the stump in its notch or notches, so as to prevent motion thereof

page_text: and of the plate H, and, consequently, of the bolt I for unlocking the same,
all which is the common and well-known action of tumblers of the best locks,
except as to the greater number of tumblers, and those tumblers being
arranged according to my inprovements in distinct sets D, E, F, G, and
adapted to be operated upon all at one time by as many distinct bits of the
key, and also as many distinct stumps, m, n, o, p, as there are distinct sets of
tumblers; but all those stumps fastened into the same flat circular plate H,
which is connected by its pin 7 with the bolt I, as aforesaid, so that the bolt I
and the plate H, together with all the stumps m, n, o, p, must of necessity
move simultaneously, and, consequently, if any one of those stumps is detained
from moving by interlocking into the notch or notches of any one or more of
the whole number of tumblers, the detention of that one stump will prevent all
motion of the circular plate H and of the bolt I. Motion is given to the bolt
from the key by means of a piece r, called the talon, which projects forward
from the bolt I, as is seen in Fig. 2. See also Fig. 6, Sheet' II., and Fig. I.
The talon passes through an opening u, Fig. H, Sheet II., in the circular
plate H, so as to avoid all interference with the motion of that plate, and the
talon r projects forwards through the plate II, into the place of the furthest
tumbler s, Fig. 2, of the set D of tumblers, the acting edge of which furthest
tumbler s is cut away to make room for the talon r, to reach to the proper
position for being acted upon by the furthest step v, on that same bit d of the
key, which bit acts by its other steps against the edges of the other four
tumblers of that set D. The key K is shewn detached in Fig. K, Sheet II.,
its four bits being marked d, e, f, g, according as they are adapted to act
against the four sets of tumblers D, E, F, G. The key K is also seen in
section in Fig. 2, as it would appear when in its place in the lock, acting with
its two bits d and ƒ against the edges of the tumblers D. and F, and also
shewing how the furthest step of the bit d of the key is to act within the
notch in the talon r, in order to move the bolt I for shooting the same; like-
wise shewing how the tumblers is cut away (as already mentioned) to make
room for the talon r; and for the same reason, the tumbler which is adjacent
to s. is also cut away part of its thickness, but leaving enough thickness of edge
to that tumbler for being acted upon by that narrow step of the bit d of the
key, which narrow step is next to the furthest step v thereof. But the
tumbler s having all its edge cut away where the key should act against it,
that tumblers is wholly useless as a tumbler, and is only introduced for
heeping the other tumblers of the same set in due place, the notch of the
useless tumblers is cut out large enough for the stump d to move therein

page_text: without ever interlocking, the said tumbler s being uscless. There are in
effect only nineteen tumblers in the whole number, as already mentioned,
although there are four sets of tumblers, and (as already mentioned) five
umblers in each set.
The parts represented in the Drawings which have now been described with
reference in detail to the Figures of those Drawings, and the arrangement
and action of those same parts, as already herein-before described in words
(as well as with the said references in detail to the Drawings), are all accord-
ing to my improvements, and may be made to form a complete lock or latch
without being combined with the other parts represented in the Drawings,
and already partly described in words, but herein-after to be more particularly
described with references in detail to the Figures of the Drawings; that is to
say, the rim A, A, and back plate C of the lock, may be made of much
smaller dimensions than represented, so as to be according to the dotted
lines X, Y, Z, Fig. 1, and only to include those parts which have been already
described, with references in detail to the Drawings. The sliding bolt I, with
the locking end thereof, in such case passing through one end of the
rim A, and shooting out therefrom when locked, as already mentioned, in the
manner of ordinary locks. Such a lock would contain the four sets of
tumblers D, E, F, G, with their stumps m, n, o, p, and circular plate H
thereof, with its pin q, and the key K, having its four bits d, e, f, g, to corrc-
spond to the said four sets of tumblers D, E, F, G, and such lock would be
according to my improvements; or one or two of the sets of tumblers may be
omitted, the corresponding bits of the key being also omitted, and the said
lock will be simpler, but still according to my improvements. And in case of
such simpler form of the said lock being made by the omission (as aforesaid)
of one or more of the sets of tumblers, the set D of tumblers, and the bit d of
the key K, must be in all cases retained, because it is that bit d which acts on
the talon r of the bolt. Also the cirular plate H, with its pin q, is in all cases
to be retained, but with only as many of its stumps m, n, o, or p, as belong
to the sets of tumblers D, E, F, or G, which are retained in the lock. For
the circular plate H, with its pin q, and so many of its said stumps as there
are distinct sets of tumblers in the lock, and distinct bits on the key, is the
means whereby the different sets of tumblers are, (according to my improve-
ments) enabled to act in concert for preventing all motion of unlocking, unless
all the tumblers in all the sets thereof are first lifted or moved by the key to
the
proper intended position for each tumbler respectively. And by means of
the said circular plate H, with its four stumps, the lock can be made with four
sets of, tumblers, as represented in the Drawings, and the omission of one set

page_text: or of two sets of those tumblers, together with omission of the stump o
stumps belonging thereto, and of the bit or bits of the key corresponding
thereto, will make no difference in the action of the lock, except as to being
more perfectly secure when there are more tumblers, and vice versâ; and in
case there are only to be three sets of tumblers and three bits to the key
(D being one of those sets, and d being one of those bits), then the other
two sets and bits may be either E, G, and e, g, or else E, F, and e, f, or els
F, G, and f, g. Or otherwise the three sets of tumblers may be conveniently
arranged at equal (or nearly equal) angular distances apart around the centre
of motion a, the three stumps in the plate H, and the three bitts of the key
being correspondingly arranged. Note, the key will in the last-mentioned case
require to be turned round one third of a revolution in the act of locking or
unlocking the bolt, whereas, in all the preceding cases (and according to all
the Figures) the key only requires to be turned one fourth of a revolution.
And in case there are to be only two sets of tumblers and two bits to the
key (one set being D and one bit being d), then the other set and the other
bit may be either E and e, or else G and g, in either of which cases the two
bits (d and e, or d and g) of the key will stand out at right angles one to the
other, about the central pipe or tube of the key, and the key will only require
to be turned one fourth of a revolution for locking or unlocking; or otherwise,
the two sets of tumblers may be D and F, and the two bits of the key d and f
in which case those two bits will be opposite one to the other, and the two
stumps m and o in the plate H will be at opposite sides of the centre a
thereof, and the key will require to be turned half round for locking or
unlocking. And note, whereas locks have been heretofore made with two bits
to the key, and one of those bits opposite to the other, each of those bits
being adapted to act against a distinct set of tumblers, and a distinct bolt
within the lock, I make no claim to such key with two bits, one opposite to
the other, as part of my improvements, unless the lock to which that key is
adapted contains a circular plate such as H, with its pin q acting in a notch
in the one bolt of the lock, and with the two stumps of that plate H acting
with and interlocking into the notches of the two sets of tumblers. The said
plate H, with its pin q, and its said stumps, being as already mentioned, the
means whereby I am enabled to make four or three distinct sets of tumblers
act in concert to prevent the unlocking of one bolt, the same means are equally
applicable for two sets of tumblers. And whereas locks have been heretofore
proposed, called quadruple locks, with four sets of tumblers arranged at equal
distances apart around the centre of motion for the key, somewhat similarly to
D, E, F, G, but each of those sets of tumblers having a distinct sliding bolt

page_text: belonging to it, with a stump fastened into that bolt for acting with and
interlocking into the notches of the tumblers of that set, the key for such
quadruple lock having only one bit (as usual in ordinary keys), and that one
bit acting when the key was turned round, first to lift the tumblers of one
set and to shoot the bolt belonging to that set, and then, after that, in turning
further round, the same bit of the key acting to lift the tumblers of the next
set, and to shoot the bolt belonging thereto, and then in like manner lifting
the tumblers and shooting the bolt of the third set; and lastly the same of the
fourth set of tumblers and bolt, so that the operation of the one bit of the key
on the four sets of tumblers and bolts would be successive for shooting those
four bolts one after the other as the key was turned round through a wholė
revolution; now I make no claim to the arrangement of four sets of
tumblers, such as D, E, F, G, in the same lock, unless the key therfor has
four bits corresponding to the four sets of tumblers, and adapted for acting
simultaneously, so that the whole number of tumblers in all the four sets will
be lifted at the same moment in the manner herein-before fully described, also
the four stumps for all the four sets of tumblers, being all fastened into the
same circular plate H, and that plate being connected by its pin q with the
one bolt of the lock, the whole number of tumblers in all the four sets are
thereby enabled to act in concert for securing that one bolt from being
unlocked, so that if any one tumbler of any of the sets is not fully lifted, or is
over lifted, that one tuinbler will effectually prevent the one bolt being unlocked
as already fully explained. The key has a notch in its bow or handle opposite to
its bit d, in order to indicate the position in which the key is to be inserted into
the keyhole, the said notch and the bit d being in all cases uppermost, but with
that bit & inclining towards the left hand of the highest position, in case of the
lock being locked, and that the key is to be inserted in preparation for unlocking,
or vice versâ for locking, and whether for locking or for unlocking, the key
is to be turned round one fourth of a revolution after it is inserted into the lock
and before it is withdrawn, and therefore its bit & will be inserted through one
of the branches of the keyhole, and withdrawn through the next of those
branches, and so of all the four bits. And note, although five tumblers are
represented in each set, that number may be varied. W, Fig. 1, is a skeleton
cover plate, fastened by screws over the tumbler of the two sets D and E, so
as to retain those tumblers in their proper places, but allowing them freedom
of motion. The tumblers of the other two sets F and G are retained in like
manner by the fixed pieces 10, which form the sides of the groove for the bolt 8
of the escutcheon lock to slide in, the end of which bolt 8, when locked,
shoots close over the tumblers of all the four sets D, E, F, G, at the parts

page_text: thereof which are nearest to the centre pin a. The cover plate B has a
extra thickness at its inside around the keyhole, and the said end of th
bolt 8 applies close behind that extra thickness when the bolt is locked and
shoots across the keyhole, in order to shut the aperture thereof. And as t
the remaining parts of the lock represented in the Drawings, which part
(although herein-before explained in words) have not been herein-befor
described with references in detail to the Drawings:-The detectors (already
mentioned) are four small steel springs 1, 1, 1, 1, Figures 1 and 6, and
Fig. D, E, F, G, fixed at one end of each detector spring by the same supports
which serve for fixing the springs of the tumblers, and formed with hooked
catches at their other ends. One such detector spring, 1, is applied with its
hooked catch opposite to a corresponding tooth 2, Fig. 1, also Fig. D, E, F, G,
Sheet II., at the en:l of that tumbler in each set of tumblers which is farthest
back from the cover plate B of the lock. And in case any one of the said
farthest tumblers being overlifted or removed farther away from the centre
pin a than its proper intended position. then the said hooked catch of the
detector spring 1, will catch the aforesaid corresponding tooth 2 of the said
farthest tumbler, so as to prevent that tumbler from returning to its proper
intended position. The lock is in such case said to be detected, and it cannot
be opened even by its own true key, because that can have no action whatever
on the overlifted tumbler, which is detained in that state by the detector 1.
And in order that the lock may become so detected in case of any other of
the tumblers being so overlifted, instead of the aforesaid farthest tumbler in
each set, cach of the said farthest tumblers (in addition to having the afore-
said tooth 2) has also a small pin 3 fastened into it, and projecting forwards
from it within suitable notches which are cut out in the outer edges of all the
other tumblers of the same set, and therefore, if any one of those tumblers is
overlifted (as for instance by action of a picklock or false key) then the
bottom of the said notch in the outer edge of the tumbler which is so over-
lifted will come into contact with the said pin 3, and, by pushing the same
outwards from the centre pin a, will overlift the farthest tumbler of the same set
into which the pin 3 is fastened, so that the tooth 2 of that tumbler will be caught
by the hooked catch of the corresponding detector spring 1 in the same manner
as if the said farthest tumbler had been itself overlifted by action of the said
pick lock or false key; wherefore any one of the whole number of nineteen
tumblers being overlifted will cause the lock to be detected by one or other of
the four detector springs 1, 1, 1, 1. And in order to undetect the lock, whenever
it is found that its own proper key will not unlock it, and thereby it is made
known that the lock has become detected in consequence of some attempt.

page_text: having been made to use a picklock or false key, then the true key, which
cannot in such case be turned round in the proper direction for unlocking,
must be turned round the contrary way as if for double locking, and then the
part v, Figure K, of the bit d of the key, which part v usually acts within the
notch in the talon r (as already explained), will. in the present case pass
onwards quite away from the talon r, and the lowest step of the next bit e of
the key K will come to act against another part 4 (Figure 6, and Figure I.,
Sheet II.), of the said talon r, which part 4 is suitably formed for being acted
upon by the said lowest step of the bite of the key for the purpose of
undetecting. And note, when the key is turned round as aforesaid in the said
double-locking direction, then its several bits will act altogether differently
against the several tumblers from their usual action in unlocking or locking,
because the bit d (which usually acts against the set of tumblers D) will be
acting against the tumblers G, and the bit e against the tumblers D, and the
bit fagainst the tumblers E, and the bit 9 against the tumblers F; the several
tumblers are thereby lifted into new positions quite different to those positions
which are suitable for unlocking or locking; but the said new positions are
suitable for unletecting the lock, because the extreme prolongations of the
notches at 5 in all the several tumblers of each set are thereby brought to
correspondence one notch 5 with another, and all those notches 5 to cor-
respond with the stump m, n, o, or p, which is then in the other parts of the
same notches, wherefore the notches 5 offer no impediment to the onward
motion of the stumps in that direction in which they will have to move for
double locking, and the key, by so acting against the said part 4 of the talon »,
will overshoot or move the bolt I a little further forwards than its usual
locking position (which position is represented in the Figures), and the said
motion of the bolt I will cause the plate II to be turned a little farther round
by action of its pin q in its transverse slot y in the bolt, and in so turning
further round than represented in the Figures the plate H operates upon all
the four detector springs 1, 1, 1, 1, at the same moment, because each of
those springs has a small lateral tooth projecting backwards from it into an
opening z, Fig. 6, and Fig. H, Sheet II., in the plate H, and the extreme end
of each of those openings z comes to act against the said lateral tooth of each
detector spring when the plate H is turned further round as aforesaid, and
thereby the detector spring is bended, as much as will withdraw its booked
catch from the tooth of the tumbler and let that tumbler go, so that it
becomes undetected, and the same action taking place with all the four
detector springs 1, 1, 1, 1, at the same moment, the lock is certain to be
undetected, whichever of those springs it may be that has caused the detection.

page_text: The four openings z, z, z, z, in the plate II are so large as to have no action
whatever on the lateral teeth of the detector. springs 1, 1, 1, 1, during any o
the ordinary motions of the plate H for locking and unlocking the bolt I of the
lock, and it is only during the aforesaid further motion of the plate H for the
purpose of undetecting the lock that the extreme ends of the said openings 2
come to act against the said lateral teeth of the detecting springs. And note
the said detectors are no part of my improvements as applied to any other
kind of tumbler locks than such as are constructed according to my improve
ments with the tumblers arranged in distinct sets, such as D, E, F, G, with
as many bits d, e, f, g, to the key K as there are sets of tumblers, and with
the stumps m, n, o, p, of all those sets of tumblers fastened into a circular
plate II, which is connected by its pin 9 with the sliding bolt I of the lock, so
as to move simultaneously therewith, that same plate H having also openings
in it for acting (as already explained) on all the detector springs at once for
withdrawing them all together in order to undetect the lock. And as to the
escutcheon lock herein-before mentioned, 6, Figures 1, 2, 5, 6, is the centre
pin for the key thereof, 7 is the key, 8 the sliding bolt, made of steel, hardened
and tempered at the narrow upper end, which shuts up the key hole for the
four-bitted key by shooting across the hole when the bolt 8 is locked, as already
mentioned. The bolt 8 is fitted into a fixed groove 10, so as to slide freely
therein; it is moved by action of the bit of the key 7, upon what is called a
fly talon 9, disposed behind the bolt in order to give a greater extent of end-
way motion to the sliding bolt 8 than the key would give thereto, by merely
acting on an ordinary talon in the bolt itself; the fly talon 9 being in effect a
lever moveable about a fixed centre pin 11, and having a pin or tooth 12 pro-
jecting forwards from it into a transverse notch 13 in the bolt 8. The said
pin 12 being farther from the centre of motion 11 than the actual talon 14,
against which the bit of the key acts, the motion which the key gives to the
talon 14 by so acting is transmitted by the pin 12 to the bolt 8, with an
increased extent of motion suitably for enabling the end of the bolt 8 to close
the keyhole of the four-bitted key, although the key 7 of the escutcheon
lock is of a small size, as is shewn by the separate Figure in Sheet II.
15 are the tumblers of the escutcheon lock, six in number; the stump 16,
which acts in the notchos of those tumblers, being fastened into the bolt 8,
and projecting forwards therefrom, through the notches of all the tumblers.
17 are the springs of the tumblers; and 18 a fixed guard opposite to the
ends of the tumblers 15; both that guard and the springs being fixed to one
of the sides 10 of the groove wherein the bolt 8 slides. 19 is a small.
skeleton cover plate, fastened. with screws to the two sides 10; it has a key-.

page_text: hole through it, and it passes across over the tumblers 15 to keep them in
their places, but allows them free liberty of motion about their centre pin 20,
which pin, as well as the centre pin 6, for the key, is fixed into the plate which
forms the bottom part of the groove 10, and the pins stand forward from that
plate through a broad notch at the end of the bolt 8. The said plate, which
forms the bottom part of the groove 10, is supported on four pillars from the
back plate C of the lock. The large cover plate B of the lock applies close
to the skeleton cover plate 19, and there is a keyhole through the cover
plate B corresponding to that through the skeleton cover 19. The addi-
tional steel plate b, b, of the cover plate B extends over the escutcheon lock,
and the keyhole therefor is formed through the said steel plate, which pre-
vents that keyhole being enlarged by drilling or cutting. The escutcheon
lock has a detector, the hooked spring 21 of which is applied at
the outside of the fixed guard 18, to which one end of the detector
spring 21 is fastened for support, and the other end, which is the hooked
catch, applies at the end of the farthest of the tumblers 15, as shewn in
Fig. 15, Sheet II., so as to catch a tooth on that end whenever the tumbler is
overlifted, in order to detain it, and thereby detect the escutcheon lock. A
pin 22 is fastened to that furthest tumbler, and projects forwards therefrom
within notches at the outer edges, and all the other tumblers 15, so that in
case of any one of these tumblers being overlifted by picklock or false key it
will, by means of that pin 22, cause the overlifting of that furthest tumbler
into which the said pin 22 is fastened, and will thereby cause the detecting of
the lock, in consequence of the said tooth at the end of that farthest tumbler
catching and being detained by the hooked catch of the detector spring 21.
The key 7 will not then be able to unlock the bolt, and, in such case, for unde-
tecting the lock, the key 7 is to be turned round in a contrary, direction, as if
for double locking the bolt, whereby the bit of the key will come to set against
another part 23 of the fly talon 9, so as to urge the bolt 8 a little farther
endway forwards than its usual locking position, and that additional endway
motion will cause the detector spring 21 to be so much bended that its hooked
catch will let go the tooth of the farthest tumbler, and thereby the lock
becomes undetected. A lateral tooth of the detector spring 21 enters into
a long slot 24, Fig. 8, Sheet II., in the bolt 8, and it is by the end of that
solt 24 coming into contact with the said tooth, that the spring 21 is bended
as aforesaid, when the bolt 8 is moved with the said additional motion.
Note, the aforesaid mechanism of the escutcheon lock and its detector is no
part of my improvements, being the same kind of mechanism and detector as
in the best locks made by my late father (and by me since his decease), under

page_text: the Patent therefor as herein-before mentioned, but the combination of the
escutcheon lock with the principal lock is an additional security thereto. And
note, the complete lock represented in the Drawings may be made with
its rim A, A, and back plate C, and cover plate B, as much shorter in length
as the dotted lines X, V, Figure 1, so as only to include the principal lock
for the four-bitted key, and the escutcheon lock. The locking and of the
sliding bolt I, (instead of passing through the guiding piece J, being fitted
through one end of the rim A, and shooting out therefrom in the manner of
ordinary locks.
And as to the combination herein-before mentioned of four door bolts for
fastening the door to which the lock is applied:-25, Figures 1, 3, 4, and 5,
Sheet I., is the circular wheel with four spiral grooves (see also Fig. 6, and
Fig. 25, Sheet II. 26, 27, 28, and 29, are the inner ends of the four door
bolts, which are all shot out at once when a turning motion is given by means
cf a handle to the wheel 25 in one direction, and are all four drawn in
again at once when the wheel 25 is turned back in a contrary direction.
The bolt 26 extends to the top of the door, 27 to the bottom, and 'the bolts
28 and 29 to the two sides of the door. The ends of those bolts are fitted
into suitable openings in the rim A of the lock, and each bolt has a strong
pin 30 projecting out backwards from it to pass through one of the spiral
grooves in the wheel 25, and the end of the pin 30 enters into a straight
guiding groove, formed by pieces 31, fixed to the back plate C, by which
means cach bolt is free to move in a direction to or from the centre of
the wheel 25, when that wheel is turned round, and its spiral grooves
act on the pins 30. The centre part of the wheel 25 is a short axis
which is fitted into suitablo sockets, one on the back plate C, and the
other in the cover plate B, see Figures 3, 4, and 5, and there is a square
hole through the centre of the axis for the reception of a square at one
end of a spindle, which will pass through a round hole in the door from
the front side thereof, and may have any convenient kind of handle on
that end which is in front at the outside of the door, so that by turning
the said outside handle the wheel 25 within is also turned, and shoots
out or withdraws all the four bolts at once, as already explained; but such
motion of the wheel 25 supposes the sliding bolt I of the lock to be with-
drawn or unlocked, for after the wheel 25 has been turned by means of its
handle, so as to shoot out all the four bolts, as in Fig. 1, in order to fasten the
door by them, then a notch in the exterior rim of the wheel 25 will have come
round exactly opposite to the end of the sliding bolt I of the lock, so that the
said bolt being then locked by action of its four-belted key K, will shoot out

page_text: through the guiding piece J into the said notch, and thereby the wheel 25 will
become fastened and prevented from turning back, so as to withdraw the four
door bolts and unfasten the door, until the bolt I has been first unlocked and
withdrawn from the said notch in the rim of the wheel 25. Note, the
extreme end of the bolt I is cut away into a hollow curve (see Fig. I.,
Sheet II., so as to avoid interference with the pin 30 of the bolt 29. That
bolt 29 extends across over the centre of the lock (see Fig. 3), and has a large
oblong opening cut through it, in order to avoid any interference with that
additional thickness of the cover plate B, which (as already mentioned)
surrounds the keyhole. For the four-bitted key the said additional thickness
extends quite through the opening through the bolt 29, and the sliding bolt 8
of the escutcheon lock (which bolt passes close behind the said additional
thickness) is not interfered with by the large bolt 29 passing immediately
before it. And note, the four bolts 26, 27, 28, 29 (or two of them), may, if
desired, have cross branches upon them near to the borders of the door, with
extra bolts on those branches, so as to obtain six, or eight, or ten or more bolts
for fastening the door; all those bolts, however numerous, being bolted or with-
drawn at once by the aforesaid action of the same wheel 25. And note, the said
combination of four door bolts to be moved all together by one action of turning
a handle at the outside of the door, and ja circular turning wheel with four spiral
grooves withinside, is no part of my improvements, but is advantageous to be
combined therewith, because the four-bitted 'key K, although of a small size,
and only shoots one bolt I, yet by means of the said combination it effectually
secures four or more strong door bolts, whereas if the shooting of the bolt I is
to fasten the door in the usual manner of ordinary locks, and that door is of a
large size, then the four-bitted key and the interior mechanism of the lock
should be of larger dimensions than in the Drawings to obtain strength. And
in .case of a lock of the kind aforesaid being constructed for a latch, in order that
it may fasten of itself (as already mentioned), then the sliding bolt I is to have
a spring applied to the tail end-or other convenient part of the bolt I, as shewn
in Figure 37, Sheet II., at S, and either with or without a lever, such as R,
in order to urge the bolt endways-forwards, so that it will be a spring or latch
bolt, and the notches in all the several tumblers must be plain .slots at
their inner ends w, w (in the manner shewn in Fig. 37, Sheet II.), so
as not to interlock with or detain the stumps m, n, o, p, when the spring bolt
I is withdrawn and unlocked (as in Fig. 37), but only when it is locked.
The said spring bolt I being unlocked by action of its four-bitted key K, so as
to draw back the spring bolt I in opposition to its spring S, and withdraw the
locking end of the spring bolt I from the aforesaid notch in the rim of the

page_text: wheel 25, and that wheel being immediately turned round for unbolting the
four door bolts before the action of the four-bitted key censes, then after that
key is withdrawn the end of the spring bolt I will remain pressed in contact
with the rim of the wheel 25 by the reacting force of the spring S of the bolt
I, and will continue in that state so long as the door remains unfastened, but
whenever the wheel 25 is turned round so as to shoot the four door bolts, and
thereby fasten the door, then the notch in the rim of the wheel 25 will be
brought opposite to the end of the spring bolt I, and that end will shoot
suddenly or latch of itself into the said notch without any action of the four-
bitted key; and when the spring bolt has so latched, the notches of all the
tumblers will interlock the stumps m, n, o, p, so as to secure the circular plate
H, and the sping bolt I from moving, and thereby that bolt I will fasten the
wheel 25 in the same manner as already described to be done in case of
a lock, by shooting the bolt, by turning the four-bitted key; and the unlocking
and withdrawing of the spring bolt I must be performed with that key in the
same manner as already fully described, except as to the unlocking being in
opposition to the spring S of the bolt I.
Having now described my said improvement in locks and latches to be
used for fastenings, I, the said John Chubb, do hereby declare that the new
Invention whereof the exclusive use is granted to me by the Letters Patent
herein-before in part recited, consists in the following particulars :-
Firstly, the improvement herein-before described and represented in those
parts of the Drawings hereunto annexed, which are marked with capital and
small letters of the alphabet for references to the said parts; the nature of
the improvement being to combine four, three, or two distinct sets of tumblers
(which sets are arranged around the centre of motion for the key) so that the
whole number of tumblers in all those sets will all be lifted simultaneously by
suitable steps on as many bits of the key as there are sets of tumblers, and a
like number of stumps (which are adapted to act in the notches of the several
sets of tumblers) being all fastened into one circular plate which is moveable
about the same centre of motion as the key, and is connected with the sliding
bolt of the lock or latch by a pin projecting from the plate, and entering into
a traverse notch in the bolt (or other suitable means of connection), so that
the bolt cannot be moved with its endway motion without communicating a
small corresponding extent of circular motion to the plate and to the stumps,
which are fastened into it, by which means all the tumblers in the different
sets will act in concert for preventing any motion of unlocking, unless all the
tumblers are duly lifted (each one to its own proper intended position) by
action of the several steps on the different bets of the key, and any one*

page_text: tumbler in any of the different sets not being sufficiently lifted, or being over
lifted, will effectually detain the circular plate, and consequently the bolt, from
be moved.
Secondly, the improvement herein-before described of combining with
the aforesaid first improvement other ordinary and well-known parts of locks,
as represented in those parts of the Drawings hereunto annexed which are
marked with numeral characters for references to the said parts, and which
parts so marked with numerals are not of themselves part of my Invention,
but the combination thereof with the aforesaid first improvement (the parts
of which are represented by letters of the alphabet) is advantageous. Namely,
the detectors 1, 1, 1, 1, applied to the several sets of tumblers are each of
them individually the same as an individual detector heretofore applied to
one set of tumblers, and each detector acts in the same manner for detecting
the set of tumblers to which that detector belongs, but as regards undetecting
the lock or latch, the manner in which the detectors are combined in the
lock or latch herein-before described with the circular plate H, and the
notches 2, 2, 2, 2, therein is a new improvement, which causes all the
several detectors to be bended back simultaneously, so as to undetect the lock
or latch whichever of the different detectors may have detected it. Also in
the act of undetecting the lock or latch all the tumblers are lifted by the key
into new positions (different from their positions for unlocking), as already
explained. Also the escutcheon lock, whereof the parts are marked with tho
numeral characters from 5 to 24 for reference to those parts, is by itself a
complete lock, similar to the best locks heretofore made, but its combination
with the aforesaid first improvement in one lock or latch, in the manner
represented and described, gives additional security against injury to the
interior mechanism of the lock by picklocks or false keys. Also the turning
wheel with four spiral grooves for shooting four door bolts at once to fasten
the door, the parts of which are marked with the numeral characters from 25
to 31 for reference to those parts, the said parts so marked are the same as
heretofore made, but the combination thereof in the same lock or latch with
the aforsaid first improvement is advantageous, by giving the greatest strength
of fastening to resist violence, and also the greatest security against picklocks
or false keys, with the use of a small and portable key, as already stated.
In witness whereof, I, the said John Chubb, have hereunto set my
hand and seal, this Twelfth day of June, One thousand eight hundred
and forty.coven
JOHN (L.S.) CHUBB.

page_text: AND BE IT REMEMBERED, that on the Twelfth day of June, in the
tenth year of the reign of Her Majesty Queen Victoria, the said John
Chubb came before our said Lady the Queen in Her Chancery, and acknow-
ledged the Instrument aforesaid, and all and every thing therein contained
and specified, in form above written. And also the Instrument aforesaid
was stamped according to the tenor of the Statute made in the fifty-fifth
year of the reign of His late Majesty King George Third.