CERTAIN IMPROVEMENTS IN LOCKS (APPLICABLE TO LOCKS FOR ALL PURPOSES), BY WHICH THEY CAN BE MADE SO AS TO COMBINE INCREASED AND PERFECT SECURITY WITH SIMPLICITY AND CHEAPNESS OF CON- STRUCTION
Year: 1852

page_text: LETTERS PATENT to Walter Henry Tucker, of Fore Street,
Tiverton, in the County of Deyon, Watchmaker, for the Invention
of "CERTAIN IMPROVEMENTS IN LOCKS (APPLICABLE TO LOCKS FOR ALL
PURPOSES), BY WHICH THEY CAN BE MADE SO AS TO COMBINE INCREASED
AND PERFECT SECURITY WITH SIMPLICITY AND CHEAPNESS OF CON-
STRUCTION."
Sealed the 1st April 1853, and dated the 1st October 1852..
PROVISIONAL SPECIFICATION left by the said Walter Henry
Tucker at the office of the Commissioners of Patents, with his
petition, on the 1st October 1852.
I, WALTER HENRY TUCKER, of Tiverton, in the County of Devon,
Watchmaker, do hereby declare the nature of the said Invention for
"CERTAIN IMPROVEMENTS IN LOCKS (APPLICABLE TO LOCKS FOR ALL PURPOSES),
BY WHICH THEY CAN BE MADE SO AS TO COMBINE INCREASED AND PERFECT SECU-
RITY WITH SIMPLICITY AND CHEAPNESS OF CONSTRUCTION," to be as follows:-
My Invention primarily consists in the principle of completely and
entirely closing or covering over the keyholes of locks during the whole
time the bolt is being unshot, so that no access to or communication
with the interior mechanism of such locks can by possibility.be effected
during the withdrawal of the bolt. .

page_text: My Invention consists, secondly, in the principle of entire prevention
(in the class of locks commonly known by the name of combination
locks) of all communication with the interior mechanism of such locks,
during the time the combination parts and their opposing or obstructing
pieces are in contact with or passing each other, as well as during the
time the bolt is being drawn back.
My Invention consists, thirdly, in the adoption of a new principle of
detection, whereby all further attempts to pick the lock are entirely pre-
vented, should previous trials to effect it have been to a certain point
successful.
My Invention consists, fourthly, in the principle of such an arrange-
ment of the wards or slides that any force applied against them shall
meet with the combined resistance of the whole, thus materially increas-
ing the strength of the lock.
My Invention consists, fifthly, in the principle of so shaping or adding
to the bolts in certain locks, that iron safes, or doors, or whatever such
locks may be fixed to, may be fastened with internal security bolts
(operated upon from the outside), such security bolts, from this shape of
or addition to the bolt of the lock, to be rendered impossible of with-
drawal, until the lock itself be opened. For example, the outer door of
a warehouse or lock-up shop may be by this means as effectually
secured from the outside, as could be the case were a person on the
inside to bolt and bar the door.
My Invention consists, sixthly, in the principle of so making the
frame of the lock, that it may be cast when made of metal, or made of
wood, so as to diminish materially the cost of production without lessening
the security or durability of the lock.
My Invention consists, lastly and generally, of means and contri-
vances by which I effectually accomplish and carry into practical execu-
tion all the principles herein-before specified; and these means and
contrivances are as follows:
My first purpose I effect by placing close behind the front plate of
the lock (which plate has two holes in it) a drum rotating parallel with
it, having in the direction of its axis an eccentric grated opening, which
is keyhole and sole access to the interior mechanism. The left-hand

page_text: hole in the front plate communicates with this opening when the bolt is
shot. In unlocking, the drum (a pin in which working in the bolt in a
slot, half of which is concentric with the orbit of the pin, and the other
half perpendicular,) rotates, when the keyhole is carried behind the
front plate, and covered over before, from the form of the slot, the bolt
can be acted upon.
My second purpose I effect by the above means, in conjunction with
the manner in which I arrange my combination slides; these are placed
in two chambers in the drum, behind the keyhole, and revolve with it,
the opposing piece being fixed at such a distance from them when the
bolt is thrown, that the keyhole is covered before the slides can come
into contact with it. My third purpose I effect by a spring pin in the
drum, which flies into a hole in the frame soon as certain of the slides
pass the opposing piece, when, the other slides being wrong, the drum is
fixed, and no further trial can be made to pick the lock. My fourth
purpose I effect by separating the slides laterally with springs only
which, yielding, communicate whatever lateral pressure they receive to
all the slides equally. My fifth purpose I effect by forming the bolt
tail somewhat in the shape of a printing T, when locked, the whole T,
projects beyond the lock, and an inside door bolt, having its handle out-
side, can be slid down upon its stem, but when the bolt is thrown, the
head of the T being then where the stem was before, the door bolt can-
not be moved. My sixth purpose I effect by making the frame so
generally solid that it can be cast complete, or made of wood. There
being no opening large enough to admit gunpowder or guncotton in
sufficient quantity, the lock cannot be injured by such means. All these
Improvements are combined and used by me in one lock, namely, this
my Detector Lock.
I may state in addition, that the lock is, as a whole, so constructed as
to be perfectly secure from all attempts to open it by gunpowder or
guncotton.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Walter Henry Tucker, in the Great Seal Patent
Office, on the 1st April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
WALTER HENRY TUCKER, of Fore Street, Tiverton, in the County of
Devon, Watchmaker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of October 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 successors, give and grant unto me,
the said Walter Henry Tucker, Her special licence, that I, the said Walter
Henry Tucker, my executors, administrators, and assigns, or such others
as I, the said Walter Henry Tucker, 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 "CERTAIN IMPROVEMENTS IN LOCKS (APPLICABLE
TO LOCKS FOR ALL PURPOSES), BY WHICH THEY CAN BE MADE SO AS TO COMBINE
INCREASED AND PERFECT SECURITY WITH SIMPLICITY AND CHEAPNESS OF CON-
STRUCTION," upon the condition (amongst others) that I, the said Walter
Henry Tucker, by an instrument in writing, under my hand and seal,
should particularly describe and ascertain the nature of the said Inven-
tion, 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 Walter Henry Tucker, 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 (that is to say):
My Invention consists, primarily, in closing or covering the keyhole
completely and entirely over during the whole time the bolt is being or
can be unshot, so that by and in consequence of such complete and
entire closing or covering over the keyhole, no access to or communica-
tion with the interior mechanism can by possibility be effected during

page_text: the withdrawal of the bolt, and this purpose I effect by placing close
behind the front plate of the lock (which plate has two holes in it,) a
solid drum or cylinder rotating parallel with it, having in its front sur-
face or cap, and in the direction of its axis, an eccentrical grated open-
ing, which is the true keyhole, and the sole inlet to the interior
mechanism. The left-hand hole in the front plate communicates with
this opening when the bolt is thrown, and through it only can the com-
bination slides be adjusted by the key. The hole to the right leads to a
central sink or chamber in the drum, which is the place into which the
key is inserted, or in which a handle may be fixed, in order to give the
requisite rotation to the drum, but which offers no communication with
the internal machinery of the lock. In unlocking, the drum (a pin in the
back part of which propels the bolt, by working in a slot in it, part of which
slot is concentric with the orbit of the pin, and the other part straight or
perpendicular,) is made to rotate, when the keyhole (being situated
eccentrically in the drum) is carried behind the front plate, and covered
over before (from the concentric form of the part of the slot in it) the
bolt can be acted upon.
My invention consists, secondly, in the principle of entire prevention,
in the class of locks known as combination locks, of all communica-
tion with their internal mechanism, whilst the combination parts and
their opposing or obstructing pieces (that is, the piece or pieces which
prevent their progress, unless they, the "combination parts," be cor-
ectly arranged in position.) are in contact with or passing each other; and
this purpose I accomplish by the adoption of means to close or com-
pletely cover over the keyhole during the time of such passing or
contact, such means being the same as described in the previous clause
(namely, by the said solid drum or cylinder therein specified being
placed close behind the front plate of the lock, and made to rotate
parallel with it,) in conjunction with the manner in which I arrange or
situate my combination slides, which are placed in two chambers in and
slide parallel with the axis of the drug immediately behind the true
Keyhole, and revolve with' it, the opposing or obstructing piece being
fixed at such a distance from them, when the bolt is thrown, that they,

page_text: together with the keyhole, must be carried behind the front plate and
covered over (all further access to the lock's internal mechanism being
then impossible,) before they can be brought into contact with it.
My Invention consists, thirdly, in the adoption of a new principle of
detection, whereby all further attempts to pick the lock are entirely
prevented, should previous trials to effect it have been to a certain point
successful; and this I carry into effect by a pin or bolt springing from
the circumference of the drum, which flies into a hole in the lock-frame,
so soon as certain of the combination slides are sufficiently advanced to
pass the face of the opposing piece, when, should the remaining slides
be incorrectly adjusted, the drum can neither be advanced nor retro-
graded, so that no further attempts to pick the lock can be made.
My Invention consists, fourthly, in such an arrangement of the
combination slides, that any endeavour to force them shall meet with the
combined resistance of the whole, thus materially increasing the strength
of the lock; and this I effect by separating the sides laterally with
springs or yielding divisions only, which causes any lateral pressure
directed against the slides to be communicated to and resisted by them
all equally and collectively.
My Invention consists, fifthly, in so shaping or adding to the bolt in
certain locks, that iron safes or doors, or whatever such locks may be
fixed to, may be fastened with internal security bolts (which may be
operated upon from the outside), such security bolts, from this shape of
or addition to the bolt of the lock, being rendered impossible of with-
drawal, until the lock itself be unlocked; this I effect by forming the
bolt tail, which is made to project beyond the lock, somewhat in the form
of an ordinary print capital letter T, but in a horizontal, instead of a
vertical position; when unlocked, the whole T, projects beyond the lock,
and inside security bolts can be so situated. as to slide in upon its stem,
but when the bolt is thrown forwards the head or transverse part of the
T, being then in the position previously occupied by the stem, the
security bolts cannot be withdrawn.
My Invention consists, sixthly, in so making the frame of the lock
that it may be cast when made of metal, or made of wood, so as

page_text: materially to diminish the cost of production, without lessening the
security or durability of the lock; and this I effect by making the frame
so generally solid that it may be cast complete, or made of wood.
I may state, in addition, that the lock is, as a whole, so constructed as
to be perfectly secure against attempts to open it by gunpowder or gun-
cotton, there being no opening large enough to admit either in such a
quantity as to cause damage.
my
All the foregoing improvements are combined and used by me in
this "Detective Lock;" and that they and it may be clearly
understood, I accompany this with drawings explanatory of such portions
as may not otherwise be sufficiently apparent.
By referring to (Figure I,) in which the lock is represented with the
bolt (c,) thrown or shot, the grated opening or true keyhole specified in
my first and second clauses can there be seen through the communi-
cating hole (A,) in the raised part, (a, a,) of the front plate, but when the
bolt is unshot, as shown in (Fig. II,) the grated keyhole cannot be
seen, as, in unlocking, the drum containing it being turned about a half
revolution, the keyhole is consequently carried behind the front plate
and covered over, no access to or sight of it being possible until the bolt
is again thrown. The combination slides (G, G,) in (Figure III,) (which
is a sectional view of the lock without the bolt,) being situated in the
drum immediately behind the true keyhole, and revolving with it, must, it
will be seen, be carried round and away from the communicating hole
(A,) (in the front plate), there represented in dots, and be of necessity
covered over, and all further access to them thereby rendered impossible,
before they (the slides) can come into contact with the faces (h, h,) of the
opposing or obstructing piece (H). Returning to (Figure I,) it will there
be seen that the security bolts (D, D,) (treated of in my fifth clause,) are
there shown as shot through their staples (E, E,) and from being in the
same vertical line with the transverse part (C) in the bolt tail, they cannot
be withdrawn; but when the lock is unlocked, the transverse part (C) in
the bolt tail being then carried back, and out of the line of action of the
security bolts (D, D,) they can then be drawn out of their staples, (E, E,)
and slid in upon the stem (F,) of the bolt tail, as shown in (Figure II.)
In unlocking, the key (which is cut at its end into as many teeth or

page_text: prongs of irregular lengths as the lock contains combination slides,) is.
pushed through the hole (A.) (Figure I,) into and through the grated.
keyhole, upon the slides behind, carrying each slide to a depth corre
sponding with the length of the prong propelling it; the key is then with-
drawn from the keyhole (the slides remaining in the various positions to
which they have been adjusted by it,) and placed, unless a fixed handle
be substituted for it, through the hole (B,) into the central chamber of
the drum, and turned round, carrying the drum with it to the extent of
its action, when the process of unlocking is completed.
The foregoing is a correct and true description of the nature of my
Invention, and of the manner in which the same is to be performed.
In witness whereof, I, the said Walter Henry Tucker, have here-
unto set my hand and seal, this Thirty-first day of March in
the year of our Lord One thousand eight hundred and fifty-
three.
WALTER HENRY TUCKER. (L.S.)