Improvements in or relating to Locks.
Year: 1895

page_text: Improvements in or relating to Locks.
We, WALTER WOLFGRAMM, Merchant, and PAUL WOLFGRAMM, Mechanician,
both of Guben, in the Empire of Germany, do hereby declare the nature of this
invention to be as follows:-
This invention comprises an improved safety-lock with adjustable tumblers, the
variation of which is effected by a key with a. bit made up of adjustable parts..
In the lock itself there are several groups of tumblers lodged one above the
other in pairs, which may vary in number and be so arranged that the separate
tumblers of each individual pair are not in contact with each other when the
lock is opened; while at the moment of closing there is a distribution or
re-arrangement in position of the different groups or pairs of tumblers, deter-
mined or brought about by the arrangement of the parts of the key-bit and
their direct action upon the lower tumblers of each group.
In the example to be described there are three individual groups of tumblers
provided, corresponding to which are three adjustable parts in the bit of the key,
while a fourth, permanently fixed, moves the lock-bolt.
By means of these three adjustable parts the form of the bit permits of about
300 distinct variations, each one differing from the other 299, and all of which
are present in the lock itself and caused by the actuating and adjustable parts
of the bit coming into contact with the tumblers. The number of variations in
the setting of the key-bit and tumblers, and consequently the security, may be
almost infinitely augmented by the addition of a fourth group or pair making
eight separate tumblers and four movable parts in the key-bit, instead of merely
six tumblers in the lock and three parts in the key-bit, respectively.
At the same time by operating the tumblers on which are formed a set of teeth
like a comb, a small pinion is actuated which renders any attempt to open the lock
by means of false keys or pick-locks impossible.
It remains to point out in what manner such locks and keys may be employed.
Supposing for instance that there are a number of doors in any dwelling, all
fitted with locks of one and the same construction, i.e. having the same tumblers;
then each lock can be closed in a different manner by means of one and the
same key all that is needful being to give the parts of the bit of the latter a
different arrangement each time. Thus not only is it possible to close all the
locks with one key, but also in locking them to set the wards of each so differently
that each separate lock is secured in a manner differing from every other.
The opening of each lock takes place subsequently with the key-bit in exactly
the same position as when that particular lock was made secure.
For the purpose, in this case, of enabling the separate positions of the key-bit
the better to be retained, the movable parts of the bit are slightly serrated on
heir contact-edges so as to prevent accidental sliding or displacement of the parts
and they may also carry a scale or figures marked laterally on the parts of the bit,
o enable the recognition of the position of the separate tumblers in the lock.
If however the key is lost or mislaid, and the fear arises of an unauthorised
pening of the lock, all that is necessary is with another key of the same size
nd construction, but with a different arrangement of the key-bit, to manipulate

page_text: the lock at once, having first opened the lock with the same arrangement of the
key-bit as that of the missing key. With the new arrangement of the tumblers in
the lock the mislaid key is in practice useless.
This safety lock is applicable to all modifications such as mortice-locks, padlocks,
safe and cashbox locks and the like. Similarly the key may be made in all sizes
and equally well with a solid as with a hollow stem i.e. a pin-key fitting on a short
projecting pin fixed to the lock-plate.
The power of adjusting the parts of the bit at right angles to the shank, as
well as also of arranging the stem or shank to be a solid or hollow shaft may
be as hereinafter described. The fixing of the several movable parts of the bit
can however be effected in manifold other ways, not here explained, as being
only subordinate matters of constructive detail, which do not affect the principles
of the invention.
When the lock is opened a hook or catch on the lower tumblers lies in a notch
of the bolt while the upper tumblers are guided by pins in suitably shaped slots
arranged unsymmetrically opposite and contrary to each other. The upper
tumblers are also held so as to be movable and rotatable by means of a fixed
pin secured to the lock-plate and lodged in a slot on which pin the other or
lower tumblers also rotate simply without being movable. Of the two pins first-
named one is secured to the lock-plate while the other is secured to the lock-bolt
and is movable therewith. By means of suitable springs the tumblers are restored
to and held when free in their original positions. The tumblers are provided with
teeth which at the moment of locking engage with each other, and also with a
pinion mounted loosely on a stud or pin secured to the lock-plate. The lock-bolt
is guided by a special stud or pin also fixed to the lock-plate and engaging with a
slot in the bolt.
Now if it be desired to close the lock the key must be inserted in the keyhole
and on being turned round to the left the bolt is gradually thrown forward,
while the projecting nose of the tumbler lying nearest to the lock-plate is lifted
out of the notch in the bolt. The holt, thus liberated, in the course of its forward
movement, carries forward with it the stud or pin secured to it, and after the
latter reaches the end of the horizontal arm of the slot in the upper tumblers
allows these to drop, until the stud or pin reaches the upper end of the vertical
arm of the said slot.
.:
:
As the left-ward turning of the key continues, the lock-bolt and stud carries the
upper tumbler sufficiently far forward for the teeth to become slightly engaged
with those on the lower tumbler; a little slide-room still remaining in the third
slot on its fixed stud. At the same time there is partial engagement between the
other teeth of the upper tumbler and the loose pinion.
When the rotation of the key has been completed as far as possible the stud
secured to the lock-plate, reaches the end of the horizontal arm of the second
slot in the upper tumbler when the teeth are finally pushed together, and a spring
at the same time pressing the tumbler downwards, causes the pinion to turn and
also the tumbler to descend till the pins are at the ends of the vertical portions
of the slots in the tumbler and thus the lock is fixed in the locked position.
The opening of the lock, is effected by turning the key in the opposite direction,
i. to the right, whereby the tumblers are raised while the pinion at the same time
is turned backwards until the pins once more resume their position in front of
the horizontal arms of the slots of the upper tumbler. Then as the turning of the
key continues further, it carries the bolt along with it by means of the neck formed
in the rear portion of the latter whereby the slots in the upper tumbler are caused
to move horizontally over their two pins. As the turning of the key finishes, the
bolt is finally thrust back in the lock, while at the same time the upper tumbler
is carried backwards by the pin on the bolt and the teeth are all disengaged. The
bit of the key being now removed from the lower tumbler the projecting nose of
the latter with the aid of the spring drops into the notch in the lock-bolt which
brings the-lock back to the original open position... –

page_text: As may be seen from what has been said above, the changes in the lock depend
upon the positions given to the tumblers on closing it, while these positions can or
may only be brought about by the use of a key to close the lock whereof the
several parts of the bit, each acting directly upon one of the tumblers are them-
selves adjustable and variable in their relative positions.
When the lock is closed the relative positions of the tumblers i.e. the steps or
differences between them, are exactly the same as those of the corresponding parts
of the key-bit when employed for the closure; consequently, so often as before
locking, the positions of the parts of the key-bit are altered, just so often also,
when locked, will the tumblers inside the lock be left in an altered position exactly
corresponding thereto.
The pinion which extends over the whole of the tumblers is mounted loosely on
a pin and free to. rotate in either direction and serves to increase the security
of the lock against attacks; it is placed entirely out of contact with the teeth
of the upper tumblers, and as soon as the lock is closed, the tumbler drops out of
contact with the pinion which is once more left free.
Supposing now that some one tries to open the lock with false keys or a
pick-lock or skeleton-key (apart from a complete want of knowledge of the
relative positions in which the lower tumblers have been left in respect to one
another, and which has been given to them when last locked by the shape of the
key-bit at the moment of locking) he will with his instrument first feel for the
furthest lower tumbler and lifting this will consequently also raise the upper
tumbler belonging thereto and forming part of the same group, until the horizontal
parts of the slots are opposite the pins; the pinion is set in motion as soon as the
teeth of the lifted tumbler come in contact and engage therewith. The next lower
tumbler is then felt for and raised in a similar manner when the teeth of the
corresponding upper tumbler also engage with the said pinion causing it to rotate
still further. Consequently the first tumbler previously brought into engagement
with the pinion is raised still further, and the same thing will occur to the second
tumbler as soon as the third and last tumbler is raised.
Thus by means of the pinion it becomes impossible by feeling with a picklock, a
skeleton-key or the like to bring the whole of the upper tumblers into line one after
the other so as to have their horizontal slots all alike in front of the pins and to
hold them fast in that position; and as this is an indispensable condition to opening
the lock and shutting it again it must be evident that every unauthorised attempt
to open the lock by means of a picklock or false keys must fail; inasmuch as that
is only possible by the employment of the proper key, having its key-bit arranged
exactly to correspond to the lower tumblers so as to touch and lift them all
at once.
A key intended to fit and open such a safety-lock as above described has the
movable parts of the bit each provided with a slot and slipped over a pin which is
firmly secured to the foremost (or topmost) part of the bit formed in one with the
key-shaft. The separate parts of the bit may be of any desired number, and are
serrated on their surfaces which are in contact the length also of each individual
part of tlie bit may vary as desired. These several parts may bear lateral marks
in the shape of numbers or scales as also the fixed or permanent end part; and
the division lines or parts may correspond to the serrations between the parts,
by means of which the desired position of the tumblers in the lock can be fixed.
The fixing of the parts of the bit may be effected by means of a slide and a nut
screwed over it, which is moved up and down by screwing to right or left on the
key-shank provided for the purpose with a screw-thread.
In a pin-key intended to fit on to a pin secured to the lock-plate the separate
movable parts of the bit are slipped with their slots over the pin secured to the
first or end part of the bit, formed in one with the key. In this case the movable
parts do not pass through the key-shank as in the previous instance, but are slipped
over it from outwards, and their fastening in any particular form or position is
effected by a nut encircling the key-shaft with a head and screw-thread.

page_text: In a modification of the key the pin may be omitted, as well as the slot. The
key-shaft is then provided with a nose on each side while the separate parts of
the bit have each a groove and they are slipped on to the shaft from the front end.
The part which moves the bolt is slipped on last and then firmly secured to the
key-shaft. The adjustment of the parts of the bit takes place as above described.
The movable parts of the bit, may however be adjusted and fixed by means of a
small screw passing through them and entering into the fixed part of the bit and
having a countersunk head; or solid bits of various forms may be inserted in the
key-shaft and secured therein by means of a screw which is screwed up with its
point in a recess in the lug of the bit.
The bit so as to vary its form may be constituted of several parts of different
lengths which are inserted and held together or fixed by means similar to that last
mentioned above.
A certain number of variations in the shape of the bit can in this manner be
obtained by interchange of the separate parts, as they are of different lengths.
Both these kinds of keys may also be constructed as pin-keys instead of with
solid shanks because the interchangeable bits, as well as the bits made up in parts
which are also interchangeable, instead of being fastened with screws, are fixed by
means of a sleeve or nut screwed on outside the key-shaft on a screw-thread specially
cut for the purpose.
Moreover the application and securing of interchangeable bits of different shapes
as well as of bits composed of loose interchangeable parts of different lengths, to
the key-shafts may also be effected in manifold other ways; as for example by
the arrangement of a conical slot on the key-shaft, wherein the several parts
of the bit are slipped, and secured by the employment of screws, springs, rings and
the like, laterally or otherwise arranged and applied.
The construction of the lock as above described can also be varied in that it
may have but one group of tumblers, on which the parts of the bit act directly.
In such a modification the lock-bolt is guided in its motion upon the lock-plate
at the back of the case by a slot passing over a fixed pin. Pivotted upon another
stud or pin similarly secured to the case are the tumblers the number of which
may be optional. In these tumblers are three suitably shaped slots connected
together and forming a compound slot within which moves a stud or pin secured
to the lock-bolt.
The number of these slots may also be optional but must not be less than two.
By means of a separate spring attached to each tumbler the latter are constantly
pressed downwards so that for example the upper end of the curved slot which
joins three separate branches or slots when the lock is open, against the upper edge
of the stud or pin.
For the better comprehension of the process of closing, a single tumbler may be
considered. This on closing the lock in consequence of the left-hand rotation of
the key and by the step belonging to it of the bit, according to its length or height,
is so far raised that one of the horizontal slots comes into position in front of the
stud or pin on the bolt to which then on the further rotation of the key, and the
consequent simultaneous forward movement of the bolt a free passage is thus
provided. Thereafter on locking, a distinct and special motion and position is
imparted to the working parts of the lock by the form of the key-bit, for the
purpose of fixing the lock.
If now the lock is to be opened again, the tumbler must be raised (by turning
the key in the opposite direction viz. to the right) exactly so far as to bring the
stud or pin out of the slot in which it had been left on closing. Then the bolt.is
shot back and the horizontal slot passes along the stud or pin when it resumes its
original open position.
The more horizontal slots there are in each tumbler or horizontal branches in the
combined slot, and the more numerous are the tumblers themselves the greater the
number of variations in the bit that can be employed.
'
Let us suppose that there are three tumblers arranged side by side in the lock

page_text: '
and three radial slots in cach tumbler. The lowest tumbler may on closing or
locking be so raised that one radial slot is found over the studior pin; the next
tumbler lying above it may have coincident with the stud another radial
slot, and finally the third may have the third radial slot coincident with the
same pin.
Such an arrangement of the tumblers can only be operated by a key the bit of
which possesses the steps corresponding to that position of the. three tumblers
which on locking raises them to such a height that each tumbler respectively
presents a different radial slot all three in line with the fixed piu or stud so that:
this is allowed free passage along them thus permitting the bolt to pass and the
locking to take place and be completed.
From what precedes however it necessarily follows that the lock left thus
closed can only be opened by a key having exactly the same form or arrangement.
of bit, as that which closed the lock; whilst by the employment of a key to which
a great variety of bit-forms may be given as well as by the number of the tumblers
and of the radial slots therein, a very large number of ways of closing and locking
the lock-mechanism each one differing from all the rest, may be obtained. But
thence follows as not only necessary but practicable the employment of a key to
which a great variety of bits can be given-either by the substitution or interchange
of differently shaped bits or of parts of bits, from which such bits can be composed>
or put together, in the key.
Dated this 16th day of April 1895.
BOULT & WADE,
Agents for the Applicants.
Improv
We, WALTER WOLFGRAMM, Merchant, and PAUL WOLFGRAMM, Mechanician,
both of Guben, in the Empire of Germany, do hereby declare the nature of this.
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention comprises an improved safety-lock with adjustable tumblers,
the variation of which is effected by a key with a bit made up of adjustable
parts.
In the lock itself there are several groups of tumblers lodged one above another in'
pairs, which may vary in number and be so arranged that the separate tumblers of
each individual pair are not in contact with each other when the lock is opened;
while at the moment of closing there is a distribution or re-arrangement in position*
of the different groups or pairs of tumblers, determined or brought about by the
arrangement of the parts of the key-bit and their direct action upon the lower.
tumblers of each group.
In the example to be described and as shown in the accompanying drawings there
are three individual groups of tumblers provided, corresponding to which are three .
adjustable parts in the bit of the key, while a fourth part permanently fixed, moves:
the lock-bolt.
By means of these three adjustable parts the form of the bit permits of a large
number of distinct variations, each one differing from all the others, and all of
which are present in the lock itself and caused by the actuating and adjustable :
parts of the bit coming into contact with the tumblers. The number of variations
in the setting of the key-bit and tumblers and consequently the security may be
almost infinitely augmented by the addition of a fourth group or pair making eight
separate tumblers and four movable parts in the key-bit instead of merely six.
tumblers in the lock and three parts in the key-bit, respectively.

page_text: At the same time by operating the tumblers on which are formed a set of teeth
like a comb a small pinion is actuated which renders any attempt to open the lock
by means of false keys or pick-locks impossible.
It remains to point out in what manner such locks and keys may be employed ;-
Supposing for instance, that there are a number of doors in any dwelling all
fitted with locks of one and the same construction, i.e. having the same tumblers ;
then, each lock can be closed in a different manner by means of one and the same
key all that is needful being to give the parts of the bit of the latter a different
arrangement each time. Thus not only is it possible to close all the locks with
one key but also in locking them to set the wards of each so differently that each
separate lock is secured in a manner differing from every other.
The opening of each lock takes place subsequently with the key-bit in exactly
the same position as when that particular lock was made secure.
For the purpose in this case of enabling the separate positions of the key-bit the
better to be retained the movable parts of the bit are slightly serrated on their
contact edges so as to prevent accidental sliding or displacement of the parts and
they may also carry a scale or figures marked laterally on the parts of the bit, to
enable the recognition of the position of the separate tumblers in the lock.
If however the key is lost or mislaid and the fear arises of an unauthorised
opening of the lock all that is necessary is with another key of the same size and
construction but with a different arrangement of the key-bit to manipulate the lock
at once having first opened the lock with the same arrangement of the key-bit as
that of the missing key. With the new arrangement of the tumblers in the lock
the mislaid key is in practice useless.
This safety lock is applicable to all modifications such as mortice-locks, padlocks,
safe and cash-box locks and the like. Similarly the key may be made in all sizes
and equally well with a solid stem as with a hollow stem i.e. a barrel-key, fitting
on a short projecting pin fixed to the lock-plate.
The power of adjusting the parts of the bit at right angles to the shank as well
as also of arranging the stem or shank to be a solid or hollow shaft, may be as
hereinafter described. The fixing of the several movable parts of the bit can
however be effected in manifold other ways not here explained as being only
subordinate matters of constructive detail which do not affect the principles of the
invention.
In the accompanying drawings
Figure 1 is a view of the bolt and some subordinate parts the cover plate having
been removed;
Figure 2 shows the lock in the opened position with a group of tumblers the
lowest of which fixes the lock-bolt.
Figure 3 shows the lock in the locked position;
Figure 4 is an interior view as seen from above, and shows the three groups of
tumblers arranged near one another and the gear above.
Figure 5 shows in elevation and in transverse and longitudinal vertical sections,
a key belonging to this safety lock with adjustable parts to the bit at right angles
to the stem or shank.
Figure 6 shows in longitudinal vertical and transverse section as well as in side
and end elevation, a key similarly provided with adjustable parts to the bit and
arranged to slide on a pin secured to the lock-plate.
Figure 7 is a modification of the last-named key having a different arrangement
of the movable parts of the key-bit.
The lock as shown in Figure 2 is opened and the hook or catch of the lower
tumbler lies in a notch g of the bolt g while the upper tumblers a are guided by
pins a and. (as shown in Figure 1) in suitably shaped slots and arranged
aunsymmetrically opposite and contrary to each other. The upper tumblers a are
also held so as to be movable and rotatable by means of a fixed pin t secured to the
lock-plate and lodged in a sloth on which pin the other or lower tumblers & also
rotate simply without being movable. Of the two pins first-named s is secured to

page_text: with slots in the bolt.
the lock-plate while s¹ is secured to the lock-bolt and is movable therewith. By
means of suitable springs f the tumblers are restored to and held when free in their
original positions. The tumblers are provided with teeth as shown at m m¹ Figure 2
and m Figure 3 which at the moment of locking engage with each other and also
with a pinion mounted loosely on a stud or pin secured to the lock-plate. The-
lock-bolt g guided by studs or pinso also fixed to the lock-plate and engaging
Now if it be desired to close the lock as shown in Figure 3 the key d (Figure 5)-
must be inserted in the keyhole and on being turned. round to the left the bolt g
is gradually thrown forward while the projecting nose b¹ of the tumbler blying:
nearest to the lock-plate is lifted out of the notch gl in the bolt. The bolt thus
liberated in the course of its forward movement carries forward with it the stud or
pin s' secured to it, until the latter reaches the end of the horizontal arm of the
slot in the upper tumblers.
As the leftward turning of the key continues the lock-bolt and studs carries.
the upper tumbler a sufficiently far forward for the teeth and m¹ to become
slightly engaged with those on the lower tumbler; a little slide-room still remaining
in the third sloth on its fixed stud t. At the same time there is partial engagement
between the other teeth of the upper tumbler and the pinion v.
When the rotation of the key has been completed as far as possible, the stud
secured to the lock-plate reaches the end of the horizontal arm of the slot in the
upper tumbler a and attains the position (shown in Figure 3) at the upper end of
the slot r through the falling of the tumbler a, when the teeth are finally pushed
together and a spring fat the same time pressing the tumbler a downwards causes.
the pinion to turn in the direction shown by the arrow Figure 3 and also the
tumbler to descend till the pins sand s' are at the ends of the vertical portions of the
slots and in the tumbler a and thus the lock is fixed in the locked position as
shown in Figure 3.
The opening of the lock is effected by turning the key in the opposite direction.
namely to the right, whereby the tumblers ab are raised, while the pinion at the
same time is turned backwards (in the direction shown by the arrow Figure 2)
until the pins and s' once more resume their position in front of the horizontal
arms of the slots r and of the tumbler a. Then as the turning of the key
continues further, it carries the bolt y along with it by means of the neck formed:
in the rear portion of the latter whereby the slots and are caused to move.
horizontally over the two pins s¹ and s. As the throwing of the key finishes the
bolt g is finally thrust back in the lock while at the same time the tumbler a is
carried backwards by the pin s' on the bolt and the teeth are all disengaged. The
bit of the key being now removed from the tumbler b the projecting nose 6 of the
latter with the aid of the spring drops into the notch g' in the lock-bolt g which
brings the lock back to the original open position as shown in Figure 2.
As may be seen from what has been said above the changes in the lock depend.
upon the positions given to the tumblers on closing it;. while these positions can or
may only be brought about by the use of a key to close the lock whereof the several
parts of the bit each acting directly upon one of the tumblers, are themselves...
adjustable and variable in their relative positions.
$
When the lock is closed the relative positions of the tumblers i.e. the steps or
differences between them are exactly the same as those of the corresponding parts
of the key-bit when employed for the closure; consequently so often as before
locking, the positions of the parts of the key-bit are altered, just so often also when.
locked, will the tumblers inside the lock be left .in an altered position exactly
corresponding thereto.
In Figure 4 are represented three groups of tumblers a and b with the pinion v
extending across the whole.
!.
The pinion is mounted loosely on a pin and free to rotate in either direction; it
serves to increase the security of the lock against attacks, being placed entirely.

page_text: out of contact with the teeth of the upper tumblers a, which as soon as the lock is
closed drop out of contact with the pinion which is once more left free.
Supposing now that some one tries to open the lock with false keys or a pick-
lock or skeleton-key, (apart from a complete want of knowledge of the relative
positions in which the lower tumblers have been left in respect to one another, and
which has been given to them when last locked by the shape of the key-bit at the
moment of locking) he will with his instrument first feel for the furthest lower
tumbler, b, and lifting this will consequently also raise the upper tumbler belonging
thereto and forming part of the same group namely a, until the horizontal parts of
the slots are opposite the pins s and s¹ the pinion is set in motion as soon as the
teeth m" of the lifted tumbler a come in contact and engage therewith. The next
lower tumbler. b is then felt for and raised in a similar manner when the teeth of
the corresponding upper tumbler a also engage with the said pinion causing it to
rotate still farther. Consequently the first tumbler previously brought into
engagement with the pinion is raised still further, and the same thing will occur
to the second tumbler as soon as the third and last tumbler is raised.
Thus by means of the pinion it becomes impossible by feeling with a picklock,
a skeleton-key or the like, to bring the whole of the upper tumblers a into line one
after the other, so as to have horizontal slots all alike in front of the pins & and s¹
and to hold them fast in that position; and as this is an indispensable condition to
opening the lock and shutting it again, it must be evident that every unauthorized
attempt to open the lock by means of a picklock or false keys must fail; inasmuch
as that is only possible by the employment of the proper key having its key-bit
arranged exactly to correspond to the lower tumblers so as to touch and lift them
all at once.
A key intended to fit and open such a safety-lock as above described with the
parts of the bit j adjustable in length is shown in Figure 5.
It has the movable parts of the bit each provided with a slot and slipped over a
pin d' which is firmly secured to the foremost (or topmost) part of the bit formed
in one with the key-shaft. The separate parts of the bit may be of any desired
number and are serrated on their surfaces which are in contact the length also of
each individual part of the bit may vary as desired. These several parts may
bear lateral marks in the shape of numbers or scales, as also the fixed.or
permanent end part; and the division lines or parts may correspond to the
serrations between the parts by means of which the desired position of the tumblers
in the lock can be fixed.
The fixing of the parts of the bit may be effected by means of a slide k and a
nut k¹ screwed over it which is moved up and down by screwing to right or left on
the key-shank provided for the purpose with a screw-thread ".
In Figure 6 is shown a barrel-key intended to fit on to a pin secured to the
lock-plate. In this case also the separate movable parts ; of the bit are slipped
with their slots over the pin d¹ secured to the first or end part of the bit formed
in one with the key d. In this case the movable parts do not pass through the.
key shank as in the previous instance but are slipped over it from outwards as
shown in the transverse section and side elevation; and their fastening in any
particular form or position is effected by a nut encircling the key-shaft with a
head and screw-thread k¹.
In a modification of the key shown in Figure 7 the pin d' may be omitted, as
well as the,, slot i. The key-shaft is then provided with a nose on each side
while the separate parts of the bit have each a groove x and they are slipped on to
the shaft from the front end. The part which moves the bolt is slipped on last
and then firmly secured to the key-shaft. The adjustment of the parts of the bit
takes place as above described and shown in Figure 6; or it may be done by means
of a slide k as shown in Figure 5.
The movable parts of the bit may however be adjusted and
small screw passing through. them and entering into the fixed
fixed by means of a
part of the bit, and

page_text: of various forms
having a countersunk head; or as shown in Figure 8 solid bits
may be inserted in the key-shaft and secured therein, by means of a scrow
is screwed up with its point in a recess in the lug of the bit .
which.
Figure 8 represents a key in which the bit is constituted of several parts of
different lengths so as to enable its form to be varied; these parts are inserted and.
held together or fixed by means similar to that shown in Figure 8.
A certain number of variations in the shape of the bit can in this manner be
obtained by interchange of the separate parts as they are of different lengths.
Both these kinds of keys may also be constructed as barrel-keys instead of with
solid shanks because the interchangeable bits as well as the bits made up in parts
which are also interchangeable instead of being fastened with screws are fixed by
means of a sleeve or nut screwed on outside the key-shaft on a screw-thread
specially cut for the purpose.
Moreover the application and securing of interchangeable bits of different shapes
as well as of bits composed of loose interchangeable parts of different lengths to
the key-shafts, may also be effected in manifold other ways; as, for example by
the arrangement of a conical slot on the key-shaft wherein the several parts of the
bit are slipped and secured by the employment of screws springs rings and the like,
arranged and applied laterally or otherwise.
The construction of the lock as above described can also be varied, in that it
may have. but one group of tumblers, on which the parts of the bit act directly.
Figure 9 shows a lock of this kind with the bolt and some of the adjacent
parts.
Figure 10.shows the lock in the
open position; and
Figure 11 shows the same in the closed position.
In this modification the lock-bolt g is guided in its motion upon the lock-plate
at the back of the case by a slot passing over the fixed pin n.
Pivotted upon
another stud or pin n¹ similarly secured to the case are the tumblers b, the number of
which may be optional. In these tumblers are three suitably shaped slots 1, 2
and 3 connected together and forming a compound slot within which moves a stud
or pin s secured to the lock-bolt..
The number of these slots may also be optional, but must not be less than two.
Atis arranged a pin for a hollow or barrel-key; but instead thereof the
arrangement may be of a hole for a solid key.
By means of a separate spring fattached to each tumbler (Figures 10 and 11)
the latter are constantly pressed downwards, so that, for example, the upper end
of the curved slot c, which joined to aud communicates with the three separate
branches, or slots, 1, 2 and 3, lies, when the lock is open, against the upper edge of
the stud or pin s.
For the better comprehension of the process of closing a single tumbler 6 may
be considered. This, on closing the lock, in consequence of the left-hand rotation
of the Hey, and by the step belonging to it of the bit, according to its length or
height, is so far raised that one of the horizontal slots 1, 2 or 3 comes into position
in front of the stud or pin s, to which, then, on the further rotation of the key, and
the consequent simultaneous forward movement of the bolt, a free passage is thus
provided. Thereafter, on locking, a distinct and special motion and position is
imparted to the working parts of the lock by the form of the key-bit, for the.
purpose of fixing the lock.
If, now the lock is to be opened again, the tumbler must be raised by turning
the key in the opposite direction riz. to the right just so far as to bring the stud
or pin out of the slot in which it had been left on closing. Then the bolt is-shot
back, and the horizontal slot passes along the stud or pins when it resumes its
original open position..
I
The more horizontal slots there are in each tumbler or horizontal branches in the '
combined slot, and the more numerous are the tumblers themselves, the greater the
number of variatious in the bit that can be employed..
B

page_text: Let us suppose that there are three tumblers arranged side by side in the lock,
and three radial slots in each tumbler. The lowest tumbler may, on closing or
locking, be so raised that the radial slot 3 is found over the stud or pins; the
next tumbler lying above it may have coincident with the studs the radial slot 2 ;
and finally the third may have the radial slot 1 coincident with s.
Such an arrangement of the tumblers can only be operated by a key, the bit of
which possesses the steps corresponding to that position of the three tumblers,
which on locking raises them to such a height that each tumbler respectively, presents
a different radial slot, all three in line with the fixed pin or stud s, so that this is
allowed free passage along them thus permitting the bolt to pass and the locking to
take place and be completed.
From what precedes, however, it necessarily follows, that the lock left thus
closed can only be opened by a key, having exactly the same form or arrangement
of bit, as that which closed the lock; whilst, by the employment of a key to which
a great variety of bit-forms may be given, as well as by the number of the
tumblers and of the radial slots therein, a very large number of ways of closing
and locking the lock-mechanism, each one differing from all the rest, may be
obtained.
But thence follows as not only necessary but practicable, the employment of a
key to which a great variety of bits can be given, either by the substitution or
interchange of differently shaped bits, or of parts of bits, from which such bits can
be composed or put together, in the key.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A lock with adjustable wards the relative positions of which are regulated
solely by the form of the key-bit, and characterised by tumblers consisting of
locking-parts such as (a) with teeth (m) and lifting parts such as (b) with teeth (m¹)
whereof the latter are only rotatable the former on the contrary both rotatable and
sliding to-and-fro in a direction parallel to the movement of the lock-bolt, on their
fixed suspension or pivot-pin, in such manner that when the lock is open the
teeth (m and m¹) are disengaged the one from the other while when the lock is
closed the locking parts are carried forward by a pin secured to the lock-bolt and
with their teeth (m) engage with the teeth (m) of the lifting parts at the moment
when the latter have been raised by the key-bit to their highest position where-
upon on the further rotation of the key the lock-bolt is completely thrust forward
and the now united locking and lifting parts fall into the locking position so that
the lock is fastened with a key-bit of any desired form at pleasure with steps of
any number and dimensions but can only be opened again by an exactly similar key
substantially as described and illustrated in the accompanying drawings.
2. In a lock such as described in Claim 1 the arrangement of a loose pinion (v)
with which the teeth (m) of the locking parts (a) engage during closure with
the object of preventing the opening of the lock by means of false keys or the like
substantially as described and illustrated in the accompanying drawings.
3. A modification of the lock described in Claim 1 in which the tumblers are
united in one group and provided with several radial slots connected by a curved
slot in such a manner that according to the length or height of the part of the bit
appropriated to each separate tumbler they present themselves in front of a pin (s)
so as to allow the latter to pass freely along them on the further turning of the key
while simultaneously the lock-bolt is shot forward and are held thereby in the
selected slot whereby the lock-mechanism assumes such a position that the lock
can only be reopened by the same key or another in exactly the same form as used
for locking it substantially as and for the purpose described and illustrated in the
accompanying drawings.
4. In keys for locks such as described the arrangement of the bits fitted with

page_text: steps in such a manner that these steps as separate loose parts are movable per-
pendicularly to the shaft and interchangeable or that the bits provided with fixed
steps of any form are interchangeable on the key-shaft substantially as and for the
purpose described and illustrated in the accompanying drawings.
Dated this 12th day of July 1895.
BOULT & WADE,
Agents for the Applicant.