IMPROVEMENTS IN LOCKS AND LOCK FURNITURE
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Walter Henry Tucker at the Office
of the Commissioners of Patents, with his Petition, on the 29th April
1865.
I, WALTER HENRY TUCKER, of 6, Southampton Street, Strand, London, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN LOCKS
AND LOCK FURNITURE," to be as follows:-
The first improvement has for its purpose the construction of locks in such
a manner that they shall not only afford security against injury by the explosion
of gunpowder or gun cotton within them, as well as security against every
method of picking at present known, but that they shall also furnish protection
from force or violence and from the destructive effects of chemical or electrical
combustion upon them, so that they may be practically relied on as a
safeguard against such agencies. And I produce these effects by the use and
the peculiar combination of a revolving drum (having a chamber in it for
the key) with a plate or slide carrier which moves in an orbit eccentric to
but around the axis for the key, carrying with it and giving action to a series
of slides (which wholly or partially surround the key) in such a manner as to
convey parts of the said slides into contact with and cause then to assume
the same arrangement as the steps of the key. These slides which serve as

page_text: a set of auxiliary key steps convey their arrangement to the real or second
series with which no direct communication can be obtained from the keyhole,
and which are so formed and combined with other parts of the lock that the
first series must pass entirely away from the second before the gating stump
can be brought into contact with them, thus making it impossible to pick the
>lock by the pressure or tentative method, while the peculiar arrangement and
action of the several parts enable the key chamber to be made no larger
than the part of the key which enters the lock, thereby reducing the space
for gunpowder to a minimum, the total inaccessibility of the real slides from
the keyhole at the same time rendering it impossible to map them or to
'measure the positions of their gatings. Security against the lock being damaged
by violence through the keyhole is provided by the use of a means specified
by me under a previous Patent of mine dated December, 17th 1861, and
numbered 3159, and which therefore need not here be explained while the
destructive powers of chemical or electrical combustion upon them are materially
.lessened by making the said locks wholly or partially of platina, or of some
other material coated or plated with platina.
The second improvement is for the purpose of rendering the large lock of
a safe, chest, or strong room less readily injured by gunpowder than is now
done, and part of the means by which I produce this effect is that of making
a portion of the case of such lock with recesses and ribs or other projections
so arranged as to interleave or fit upon or into other projections and recesses
on the inner surface of the door to which such lock is applied, so that it shall
be necessary to force the said door and lock case some distance asunder to
insert gunpowder or other explosive material between them.
A second part
of the said means consists in the use of one or more transverse pieces or
bars so formed and arranged that when the ordinary bolts are thrown forward
the said transverse bars may be acted on by cams, springs or other suitable
means so as to be carried into and fill up the space which would otherwise
remain open behind the heads of the said bolts, and thereby prevent the
insertion of gunpowder into the said space. And a third part of the said
means consists in placing the whole or a portion only of the system of bolts
comprised in such large lock, and at times the small lock which secures them
also at the back of the fire-proof chamber usually attached to the case of the
said large lock, instead of placing them between the said fire-proof chamber
and the door, thereby lessening the space for gunpowder in the said case.
The third improvement is for the purpose of preventing damage to the
locks of a safe, chest, or strong room by force exerted on the handle by which

page_text: the large lock bolts are thrown. And this I effect by such a formation and
arrangement of the follower connected with such handle and of the bolts of
the said large lock that they communicate with each other when the small or
security lock is unlocked, but are disconnected and the handle left free to
5 revolve when the security lock is locked out. This improvement is applicable
to all locks wherein one or more bolts are actuated by a handle, and its use
therefore for all such locks is hereby specified by me.
The fourth improvement consists of such a form and arrangement of the
parts through which the handles of a lock convey motion to the spring or
latch bolt that the advantages of lessened friction, an equable action in both
directions, and an increase of power by the handle proportioned to the in-
creasing resistance of the spring as the bolt is drawn back, may be obtained
without injurious disturbance of the general arrangements of the lock. And
I effect this by the use of a double horned cam working on a centre either
above or below the follower through which the spindle of the handles passes,
which cam I act upon by an arm from the said follower so as to turn it on
its centre and bring one or the other of its horns against parts of the latch
bolt which move on either side of the centre of the cam, the connection of
the cam and the follower being so arranged that the arm of the follower
conveys its motion to the cam at a continually decreasing distance from thie
axis of the said follower, whereby the power by the handle increases with the
increasing resistance of the bolt spring.
The fifth improvement consists of such modifications of locks which are
constructed so that their combination security parts move in a circle around
the axis of the key, as exampled in the several kinds of locks known as
Bramah's, Cotterill's, or Yale's, or modifications of either of the same, that
their opposing security parts (that is the steel locking plate in a Bramah
lock, the circle of stumps in a Cotterill lock, or the outer drum in the Yale
lock, which in such locks are either rigidly fixed or have but a limited circulatory
movement around the key) may be free to revolve with or before the combina-
tion security parts themselves if any attempt be made to pick or to force
the said locks through the keyhole, and this I effect by doing away with
the customary fastenings which are used to hold the said opposing security
parts, and by so forming the said parts or the pieces in which they are fixed
or placed that if they are moved from their normal positions a stump or piece
connected with the bolt and acted on by a spring or weight cannot thereby
engage with a disc or piece attached to the drum, which in such locks usually
contains the combination security parts, and which may therefore be made

page_text: to pass continuously round in the lock without carrying the bolt or injuring
any part of the lock. In making spring locks on this plan I use a locking
piece so formed and acted on by the drum, or some part moving in connec-
tion with it, that it not only serves to lock the bolt when the true key is used
in the proper locking direction, but if a false key be turned in the lock in
either direction the like effect is produced, thus supposing the lock not to
have been locked by the owner, any attempt to pick it would render it more
secure than before. In such locks also I customarily place the spring which
impels the bolt on the bolt itself so as to travel with it, by which means the
resistance of the spring has not to be overcome by the key.
The sixth improvement is for the purpose of making a changeable lock on
a modification of the Bramah or slider construction, and this I effect by the
use and the peculiar arrangement of a second drum in addition to the drum
in which the sliders are customarily placed in locks of this description, in
which second drum I place another set of sliders so formed as to constitute
a series of moveable locking plates, and which bear such a relation to. the
sliders in the other drum that projections from one of the sets must pass into
gatings or recesses on the others to enable the lock to be opened, each
of the drums is provided with or gives motion to a disc so formed that
the two dises must be brought into a certain relation to each other to
enable a stump or piece connected with the bolt and acted on by a spring
or weight to engage with one or both of them so that they may carry back
the bolt. This particular relation of the discs to each other can only be
produced by the use of the true key, were a false key used tho necessary
correspondence between the discs could not take place, and the two drums
would be moved continuously round in the lock without injury to its parts.
When the lock is unlocked the projections from one set of sliders are in the
gatings of the others, and the key on being pressed into the lock adjusts the
both sets together, when from a movement which one drum has in the other it
moves far enough to separate the two sets of sliders before giving motion to the
other drum, the result of which is that when the key has completed its
revolution and locked out the bolt, the set of sliders on which the key directly
acts may be restored to their normal positions, leaving the other set which
have no separate impelling springs arranged to the particular combination of
the key used in locking, to which particular combination the other sliders
must be again arranged in order to open the lock. I render this improvement
by suitable modifications applicable to all locks in which the combination
security parts move in a circle around the axes of the key whether the

page_text: direction of motion given to the said security parts or sliders by the key De
borizontal, vertical, or otherwise. The particular kind of changeable key
which is suitable for locks of this kind having been before specified by me
under a previous Patent of mine dated December 17th 1861 (number of
Patent 3159) need not here be described.
The seventh improvement is for the purpose of making a keyless lock in
so simple yet effective a manner that it may be applied to the many every day
purposes, for which mere spring snaps or other inexpensive fastenings are
now employed. And I effect this by the uso of a moveable plate or plates
so formed and arranged (and contained in a suitable case) that unless certain
notches or gatings in such plates are brought into a particular position the
hasp which such plates are used to secure cannot be released. By preference
I use one or more pairs of plates in which caso the two plates in each pair
bear such a relation to each other that one of the two acts upon the other to
convey it to its right position direct communication by the hand being
obtainable with one only of them. And in order to give increased security to
locks so constructed, I make false notches of such a depth on the gating
edgo of the plate which the hand can directly actuato that a portion of the
hasp or a locking piece used in conjunction with it will bear against the edgo
of the other plate only when it is in the aforesaid false notches, by which
means there will be a great difficulty in finding the right positions for the said
plates. I customarily make the said plates circular, and actuate them by a
projection or pin attached to one of them, thero being usually a dial and
index on the case to guide the user, but I do not limit myself to any particular
form of plate, nor to any mode of giving action to the same, nor to the use of
a dial and index, which may be dispensed. with if desired.
The eighth improvement is for the purpose of remedying evils which have
become apparent in some lock furniture specified by me under a former
Patent of mine No. 3159 (1861), wherein I claimed to place on over the
screwed spindles (therein described) "close to the door a washer or collar
having a hole in it to fit the spindle without turning on it, and provided
"with teeth, sinks, or spaces in it (usually on its edge or circumference),
into or upon which teeth, sinks, or spaces a click, pin, or screw attached to
"the handle (which screws on to the wormed edges of the spindle similar to
"
"
Duce's) is made to fasten." Experience has shown that the said washer or
collar by being brought close to the door wears away its surface, and that
part of the present improvement which is intended to remedy this evil consists
in placing the said washer between the inner surface of the rose (which way

page_text: be screwed or otherwise fastened to the door) and the knob, so as thereby to
transfer the friction of the washer to the rose.
Another part of the improvement consists in making the roses with recesses
on their outer surfaces so shallow as to permit the screw in the knob seat to be
adjusted over the edges of the said recesses in place of making the roses with
the deep recesses specified by me in the Patent herein-before mentioned, it
having been found difficult to adjust the said screw in the knob through the
rose as was therein necessary.
Another part of the improvement consists in the use of a covering rose to the
said furniture, so arranged as to be screwed on to the circumference of a thin
plate fixed to the surface of the door under the washer, so as thereby to
conceal the screw in the knob seat if desired.
The ninth improvement is for the purpose of more effectively securing the
upper or covering rose to the under rose or plate in such kinds of lock
furniture as are made with a covering rose, it being found that the upper
rose is liable to become loose, and to unscrew from the under rose by the
unintentional pressure of the fingers against the upper roso when the knob
is turned in the direction to unscrew the said rose. And I effect this by the
use of a moveable dog or bolt so formed and placed as to be acted on by a
part connected with the knob, and thereby to hold the two roses together so
as to prevent their becoming detached from each other, unless the knob- and
the outer rose are turned in contrary directions to each other, by which means
they cannot become unintentionally separated.
The tenth improvement is for the purpose of so constructing furniture for
locks that while there shall be no separate covering rose there shall also be
no transverse screw or pin into or through the adjusting knobs of such
furniture. And to effect this I screw the adjusting knobs on to the wormed
angles of the spindles in the manner patented by Mr. Duce in 1842 (number
of Patent 9364) but to prevent the knob being unscrewed after it has been
adjusted to suit the thickness of the door to which it is applied in place of
the transverse screw in the knob which Duce used for the purpose.
I place
on over the spindle in a recess on the outer surface of the rose a slide or stop
which has a hole in it to fit the spindle without turning round on it, and is
otherwise so formed as to fit into or upon certain irregularities of the base
or seat of the knob, so that after the knob has been screwed to its correct
position on the spindle the said slide or stop may be shifted from its position
in the rose into or upon the irregularities of the knob, and thereby keep it
from turning again on the spindle until the slide or stop is restored to its

page_text: normal position in the rose. The necessary sliding action for the slide or
stop on the spindle may be given by a spring placed between the rose and a
portion of the said stop, but I prefer to worm a portion of the said stop and
actuate it by a separate piece (which is also contained in the recess of the
rose) having a wormed hole through its centre fitting the wormed part of the
stop in such a manner that as the said separate piece is turned in one direction
it will carry the stop into or upon the irregularities of the knob, and release
it from them again when turned in the contrary direction.