Improvements in Locks.
Year: 1891

page_text: Date of Application, 31st Oct.; 1891
Complete Specification Left, 30th July, 1892--Accepted, 3rd Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements in Locks.
I, FREDERIC BARKER, of 11 Snow Hill, Wolverhampton in the County of
Stafford, Lock Manufacturer, do hereby declare the nature of this invention to be
as follows:-
This invention has for its objects, greater security in the locking mechanism of
locks, and (but more especially in the case of cupboard and gate locks and the
like in which it is desirable to use small or narrow cases) to enable a longer shoot
than usual to be given to the bolt compared with the length or breadth occupied by
the mechanism.
The above objects are attained, according to this invention, by means of duplex
levers, of which the simplest form consists of a single pair. The hinder lever is
pivoted to the case on one side of the vertical axis of the key hole, and the other
lever is pivoted to the case on the opposite side of such axis and passes across in
front of the hinder lever. The hinder lever carries a stump which projects through
a longitudinally curved slot in the other lever and into a gating in the bolt. The
gating in the bolt is formed of a longitudinal slot having a downward, and preferably
also an upward, notch at each end. The outer end of each lever curves down as a
horn below the inner end of the other lover, and as the key is turned in one direc-
tion it bears against such curved down portion of one of the levers and raises it,
and consequently the other lever also. As the key continues to be turned in such
direction, it slides under the edge of the lever with which it first came in contact
until, as it approaches its middle position, it bears against the edge of both the
levers; and as it is turned downward from such position it passes out of contact
with the lever with which it first engaged, and the outer downwardly curved end of
the other lever bears on the key and is not only itself prevented from moving
downwards until the key allows it to do so, but until then prevents the other lever
also from moving downwards. It will thus be seen that the duplex levers are held
up by the key through a much longer portion of its movement than is the case
with a single lever, or any number of levers pivoted to a common axis, and that
consequently a correspondingly longer shoot is given to the bolt. The levers inter-
lock with the bolt, at each end of the shoot by the stump carried by the back
lever moving into the downward notches in the bolt. The upward notches
are for increased safety against the lock being picked, as will be readily
understood.
For additional safety, I use an extra pair of levers, corresponding to those above
described, and pivoted respectively to the pivot pins thereof, the hinder one having
a stump projecting through a longitudinally curved slot in the other and into the
gating in the bolt. The stump on the inner lever of the first-mentioned pair
passes through a vertically curved slot in the hinder lever of the second pair, and
through a gating in the outer lever of such pair formed of its longitudinally curved
slot and of an upward and downward notch at the inner end thereof; and when
both pairs of levers are in their downward position, as when the lock is locked or
unlocked, the two stumps are side by side, both resting in a notch of the gating
through the bolt. This additional pair of levers makes the lock peculiarly difficult,
if not impossible, to pick, because if one pair of levers is raised otherwise than
normally with the other pair the stump on the inner lever of the first pair will be
within one of the notches of the gating through the outer lever of the second pair
and will thus interlock the one pair of levers with the other pair.
For still further safety, any convenient number of levers may be used at the face
of the outside lever of the second pair.

page_text: In order to allow the key to throw the bolt the extra shoot which my arrangement
of levers permits of, a portion of the bit between the nose which bears against
the bolt and the shank of the key is cut away so as to clear the corners of the key
gating in the bolt.
The lever mechanism may be constructed in the manner above described for the
purpose of security, even in cases where a long shoot of the bolt, compared with
the length or breadth of the mechanism, is not required.
Dated this 30th day of October 1891.
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Locks.
I, FREDERIC BARKER, of 11 Snow Hill, Wolverhampton in the County of
Stafford, Lock Manufacturer, 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 has for its objects, greater security in the locking mechanism of
locks, and (but more especially in the case of cupboard and gate locks and the like
in which it is desirable to use small or narrow cases) to enable a longer shoot than
usual to be given to the bolt compared with the length or breadth occupied by the
mechanism.
.
The above objects are attained, according to this invention, by means of duplex
levers. The simplest form of these levers, when for use either to enable a long
shoot to be given to the bolt, or for the purpose of ensuring greater security,
consists of a single pair. An arrangement of a single pair of duplex levers for use
for enabling a long shoot to be given to the bolt is illustrated by Figures 1 to 4
of the drawings herewith, of which Figure 1 is an elevation, with the cap-plate
removed so as to shew the interior mechanism, of a lock suitable for employment
as a cupboard lock or the like, the bolt being shewn in such view as shot into its
extreme position in one direction (being locked or unlocked accordingly as it is
considered as being used right or left handed) with the levers in their downward
position due to the key being turned clear thereof. Figure 2 is a corresponding
view to Figure 1, but shews the bolt in its mid position, and the levers consequently
in their upward position. In Figures 1 and 2 the bolt B is indicated by broken
lines. Figure 3 is a detached elevation of the bolt; and Figure 4 is a vertical
section online x x of Figure 3. A A are the duplex levers, of which the hinder
lever A is pivoted to a pin a¹ fixed to the case on one side of the axis of the key
pin, and of which the lever A is pivoted to a pin a fixed to the case on the opposite
side of such axis. The lever A passes immediately across in front of the lever A¹.
bis the drill pin for the key, but of course in some descriptions of locks a solid-
pin key may be used. The hinder lever A¹ carries a stump e which projects through
a longitudinally curved slot c¹ in the other lever and into a gating d in the bolt B.
The slot is shewn as curved at its lower side and of an angular shape on its
upper side of which a part fits down upon the stud c when the levers are down. It
will be obvious, however, on a consideration of the operation of the mechanism,
that the shape may be varied to some extent. The gating in the bolt is formed
of a longitudinal slot d having a downward notch d', and preferably also an upward
notch d, at each end. The outer end of each lever A A' curves down as a horn
below the inner end of the other lever, as shewn, and as the key is turned in one
direction it bears against such curved-down portion of one of the levers and raises
it; and owing to the engagement of the stump c carried by one of the levers with
the slot c¹ formed in the other lever the raising of either lever causes the other to
move up also. As the key continues to be turned in. the same direction, it slides
along under the edge of the lever with which it first came in contact until it

page_text: reaches its middle position when it commences to bear against the edge of the other
lever; and as it continues to be turned in the same direction it moves downwards
from such position and passes out of contact with the lever with which it first
engaged, and the outer downwardly curved end of the other lever bears on the key
and is not only itself prevented from moving downwards until the key allows it to
do so,
but until then prevents the other lever also from moving downwards on
The edges of the levers
account of the engagement of the stump c with the slot c¹.
are, of course, shaped in such manner that, during a portion of the movement of
the key, they are simply held in their upward position, as shewn by Figure 2,
while the same portion of the movement of the key operates to shoot the bolt the
required distance to lock or unlock it. It will thus be seen that the duplex levers
are held up by the key through a much longer portion of its movement than is the
case with a single lever, or any number of levers pivoted to a common axis, and
that consequently a correspondingly longer shoot is given to the bolt. The
levers A A¹ interlock with the bolt at each end of the shoot by the stump c carried
by the hinder lever moving into the corresponding downward notch in the
gating d of the bolt. The upward notches d² d² of such gating are for increased
safety against the lock being picked, as will be readily understood. The key-
gating of the bolt, and also the bit of the key, are formed in a manner well known
as adopted in the case of long-shoot bolts. The bit end of a key for use with the
lock illustrated by Figures 1 to 4 is shewn by Figure 5. The bolt is formed with
an opening C therethrough, out of the upper side of which leads the key-gating e.
A portion e' of the bolt on each side of the key-gating is formed thin, as shewn by
Figure 4, and a ward or opening is cut through the bit of the key in position to
pass over either of the thin portions e¹, and thus allow the part g of the key to
operate directly against the side or edge of the key-gating e during the whole
movement of the bit within such gating. Indeed, but for the thin portions e¹ and
ward a deep and narrow key-gating such as e, necessary to enable a long shoot
to be given to the bolt, could not be used.
Figures 6 to 9, inclusive, illustrate a modification of the invention in which an
extra pair of duplex levers are employed, so as to secure increased safety in addition
to the advantage of enabling a long shoot to be given to the bolt. Of these
illustrations Figure 6 corresponds to Figure 1, that is to say, the bolt is in its
extreme position one way and the levers are down. Figure 64 is a view of the
levers in the position they assume when raised by the key, the case and bolt being
omitted for simplicity and convenience of illustration. Figure 7 is a corresponding
view to Figure 6, but shews the levers in the position which they would assume
during an attempt to tamper with the lock by raising one of the extra levers.
Figure 8 corresponds also to Figure 6, but shews the levers in the position they
would assume under an attempt to tamper with the lock by raising one of the back
pair of levers; and Figure 9 is a detached view of the lever A³ hereinafter
described. In this modification the hinder pair of levers A A¹ are the same as in
the modification previously described; but an additional pair of duplex levers A² A³
are employed, of which the hinder lever A³ is pivoted to the pin a¹ on which the
lever A is pivoted, and the lever A is pivoted on the pin a on which the lever A
is pivoted. The stump c (which corresponds to the stump c shewn by Figures 1
and 2, but is made preferably half the width thereof) projects from the lever A¹
through a slotted gating in the lever A (as in the former described modification)
and passes also through a vertically curved slot i (see Figure 9) in the lever A³,
and through a gating formed in the lever A which consists of a longitudinally
curved sloth communicating with a vertically curved slot h¹ at its inner end, the
vertically curved slot h' forming in effect an upward and downward notch at the
inner end of the slot h. A stump k, carried by the lever A³, projects through
the longitudinally curved sloth in the lever A. Both the stumps c and k project
also into the gating through the bolt B, and when the levers are down in their
normal position, as shewn by Figure 6, the two stumps ck are in position_side_by
side and both within one of the notches d' of the gating through the bolt B. The

page_text: gating through the bolt B is as illustrated by Figure 3; but the lettering is
omitted on Figures 6, 7 and 8, to avoid confusion. The levers A' A³ are each
shaped down at their outer ends similarly as the levers A A', and if either of them
is lifted by the key the other is raised also on account of the engagement of the
stump k, carried by one of the pair of levers, with the slot through the other
lever. The slot h allows for the sideway movement of the stump k in relation to
the lever A; and, as both pairs of levers are properly raised, the slot allows
the stump c also to enter therein. Both pairs of levers are shewn in their raised
position by Figure 64 with both the stumps c and k within the sloth. As previously
shewn, either of the levers A A' is raised if the other of such pair is raised, and
either of the levers A' A' is raised also if the other of the pair is raised; but
neither of the levers A. A' can be raised by either of the levers A2 A³, nor can
either of the levers A² A³ be raised by either of the levers A A, and any attempt
to raise a lever of one pair without simultaneously raising one of the levers of the
other pair will cause an interlocking or jamming of the parts. Figure 7 illustrates
the manner in which the parts are interlocked or jammed if either of the levers A²
or A³ is raised without at the same time raising one and consequently both of the
pair of levers A A. The lever A³ being raised (either directly or through the
medium of the lever A³) while the lever A' is down causes the lower end of
the vertically curved slot of the lever A2 to come up against the stump c of the
lever A', and the stump being thus within a notch in the lever A² the lever A'
cannot itself be raised because its stump c is securely held sideways within the
notch. As the lever A¹ is thus locked in its downward position the lever A
is also locked in such position as it cannot be raised independently of the
lever A. Figure 8 illustrates the manner in which the parts are interlocked or
jammed if either of the levers A or A¹ is raised without at the same time raising
one and consequently both of the pair of levers A2 A³. By raising the lever A
(either directly or through the medium of the lever A) while the lever A² remains
down the stump e carried by the lever A' is brought up into the notch formed
by the upper end of the vertically curved slot h' of the, lever A, and this notch
being around the top end of the stump e prevents the lever A2, and consequently
the lever A³ also, from being raised, because the outer side of the notch holds
against the side of the stump. Figure 10 illustrates the bit end of a key suitable
for employment with the lock illustrated by Figures 6 to 9, being in fact the same
as the key illustrated by Figure 5 except for the additional nosings to operate
the additional levers.
I will now proceed to illustrate modifications of the invention in which duplex
levers pivoted on opposite sides of the axis of the key pin are employed for the
purpose of security in cases where a long shoot of the bolt, compared with the
length or breadth of the mechanism, is not required. The simplest modification
for this purpose is shewn by Figure 11 which is a corresponding view to Figure 1
but illustrates a drawer or cabinet lock, the outer plate of the cap being
supposed to be cut away. A hinder lever D' of a pair of levers D D', which is
shewn also as a detached view Figure 12, is pivoted to a pin a fixed to the case
on one side of the axis of the key pin, and carries a stump which projects through
a gating m in the front lever D which is pivoted to a pin a' fixed to the case on
the opposite side of such axis; and the stump projects also through a gating in
the bolt B of the character of the gating described with reference to the previous
modifications. It will readily be seen that the lever D¹ cannot be raised unless
the lever D is raised in advance thereof, as the stump interlocks when both the
levers are down, as shewn, with the upper outer corner of the gating m through the
lever D; and if the lever D is pushed up to its full height independently of
the lever D' a downward notch m' at the bottom of the gating m will come around
the stump 1, and the outer edge or side of such notch will then prevent the stump /
from being raised and the lever D' will consequently be locked down. Moreover,
as there is no endway pressure of the stump against the lever D such as is the
case in ordinary lever lock mechanism, there is no guide, in picking the lock, as

page_text: to the height to which to lift the lever. A further modification (as applied by way
of example to a drawer or cabinet lock) is shewn by Figures 13, 14 and 15, of
which Figure 13 shews an arrangement of two levers pivoted on the same pin a
and for which no claim is made when used together simply as shewn in such view;
of which Figure 14 shews a combination therewith of levers pivoted to a pin a¹ on
the opposite side of the axis of the key pin and with the hinder lever of the pair
shewn by Figure 13 raised as if an attempt were being made to tamper with the
lock by raising such lever; and of which Figure 15 shews the combination
illustrated by Figure 14, with the parts in position due to the lock being tampered
with by raising one of the extra levers shewn by Figure 14.
When the
Referring first to Figure 13, the hinder lever E' carries a stump n which projects
through a vertically curved slot n' in the front lever E and into a gating in the
bolt B and the lever E carries a stump o which projects also into the gating in
the bolt B. The bolt B is shewn by broken lines as in the other views. The
gating through the bolt is formed of a longitudinal slot p having upward and
downward notches at each end and at the middle thereof, as shewn.
levers E E¹ are in their downward position, as shewn by Figure 13, the stump of
one of the levers is in the downward notch at one end of the slot p through the
bolt, and the stump of the other lever is in the downward notch at the middle of
such slot; and when the levers have been properly raised by the key, and the bolt
shot to the opposite end of its shoot, the stump which was previously in an end
notch is lowered into the middle notch and the stump which was previously in the
middle notch is lowered into the other end notch. The upward notches are simply
for additional security, as will be well understood. Referring now to Figure 14,
one or any desired number of levers F, pivoted to a pin a¹ on the opposite side
of the axis of the key pin to that on which the pin a is fixed, are used in
combination with the levers E E which have been described with reference to
Figure 13. Each of these levers F is formed with gating through which the
stumps n and o pass. The gating for the stump n is formed with a slot q, as shewn,
through which the stump n projects when the levers are in their downward position,
and within which it vibrates as the levers are worked by the key, and with an
upward notch into which the stump n is raised if the lever E' is raised independently
of the levers F, the stump being shewn within the notches in Figure 14, due to the
lever E having been improperly raised in relation to the levers F. The gating
for the stump o is formed as a vertically curved slot r, of which the upper end is
down upon the stump when the lever is down, and of a sideway notch s which
allows for the vibration of the lever E which carries the stump o. The vibration
is at first very small as the levers are raised by the key, and a slight play in the
vertically curved slot r will allow for it; but as the levers approach near to their
upward position the vibration becomes more considerable and the stump o enters
somewhat within the sideway notch 8. The vertically-curved slot r is shewn to
project below the notch s. This, however, is for additional security. and is not
required when operating the mechanism by the key. It is clearly shewn by
Figure 14 that when the lever E and levers F are in their downward position the
stump o is locked by the outer top corner of the slot r. It will be seen also from such
view that when the lever E' is raised, as shewn, and the stump n consequently
brought up into the notch of the front lever F, such lever (and of course any
corresponding levers) are locked by the engagement of the top outer corner of the
notch with the stump n, and that consequently also the lever E is locked as it
cannot, as before explained, be raised while the levers F are down. It will also be
seen, on reference to Figure 15, in which one of a set of levers F is supposed to
have been improperly raised, that if either of such levers is raised otherwise than
with the other levers by the proper key all the other levers F will be jammed, as
the raising of the lever F raises the stump n (and consequently the lever E¹) and
brings such stump into the upward notches of all the other levers F and
consequently prevents then from being raised. The jamming of the levers F locks
also, as before explained, the lever E. It should perhaps be explained that, when

page_text: the levers are all down, the stump n rests normally on the lower edge of the gating g
of each lever F, and that consequently, if either of such levers is raised, the stump
is immediately raised therewith. If only one lever F is used, and such lever is
raised independently of the lever E, the lower end of the slot r comes under the
stump o and the outer edge of such portion of the slot locks the stump and prevents
the lever E from being raised.
The term "duplex" is used in this Specification conventionally, not as signifying
merely a pair of levers, but as indicating that one or more of the levers are pivoted
on one side of the axis of the key pin (that is to say, the axis of the stem of the
key when in position within the lock), and one or more are pivoted on the
opposite side of such axis; the arrangement or pivoting being in such sense
"duplex."
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The employment, in a lock, of duplex levers (that is to say, levers pivoted
on opposite sides of the axis of the key pin) geared together, substantially as
described.
2. In a lock, duplex levers formed with downwardly projecting horns at their
outer ends for use in enabling a long shoot to be given to the bolt, substantially as
described.
3. In a lock, the combinations of duplex levers, geared together by means of
stumps and gatings so that if one or more are raised independently of another or
others, such other or others will thereby be locked so that it or they cannot be
raised, substantially as described.
4. The several combinations of lever mechanism for locks in which duplex
levers are employed, substantially as described with reference to the drawings
herewith.
Dated this 29th day of July 1900
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicant.