Im- PROVEMENTS IN LOCKS AND KEYS
Year: 1873

page_text: LETTERS PATENT to Bristow Hunt, of Serle Strect, Lincoln's Inn, in
the County of Middlesex, Gentleman, for the Invention of "Im-
PROVEMENTS IN LOCKS AND KEYS."-A communication from abroad by
Daniel Klahr Miller and Allen Middleton, jr., both of Philadelphia,
Pennsylvania, United States of America.
Sealed the 20th October 1873, and dated the 25th August 1873.
PROVISIONAL SPECIFICATION left. by the said Bristow Hunt at the
Office of the Commissioners of Patents, with his Petition, on the
25th August 1873.
I, BRISTOW HUNT, of Serle Street, Lincoln's Inn, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN LOCKS AND KEYS," (a communication to me from
abroad by Daniel Klahr Miller and Allen Middleton, junior, both of
Philadelphia, Pennsylvania, United States of America), to be as
follows:-

page_text: cating or increasing the cost of the same, to facilitate the construction of
keys for many tumblered locks, to prevent the destroying or defacing of
a seal by mere tampering with the lock, and to enable a bolt or hasp to
be readily withdrawn from and inserted into its place in a lock casing
without removing the cap plate from the latter.
In one form of the improved lock the case is circular, with a portion of
one edge cut away to form a recess, across which slides a bolt or hasp
adapted to the interior of the case, and hooked at its outer end or
recessed at one side for the reception of a staple; the latter being readily
detached when the bolt is thrust outward, but retained within a circular
opening formed by two recesses when the said bolt is thrust inward.
When locked the bolt or hasp is contained almost entirely within and
protected by the casing, so that the difficulty of breaking or cutting the
same in order to detach the said staple is much greater than with the
exposed hasps of ordinary padlocks. In this form of lock two distinct
sets of vibrating spring tumblers, hung to separate pins and operated
simultaneously by one key inserted through a keyhole, are combined
with a single bell-crank lever or dog, the hooked arms of which when
the whole of the tumblers are properly adjusted by the key enter notches
in the said tumblers, thus permitting the dog to vibrate to a sufficient
extent to release the bolt or hasp, which springs outwards from the case,
and releases the staple. When the bolt is pushed back into the case
the dog releases the tumblers, which spring to their original positions,
and at the same time the said dog enters a recess in the side of and
retains the bolt.
One of the tumblers of the upper set has a cam-like incline, which
when the said tumbler is turned, say to the right by a spring, acts upon
one arm of the dog, and forces the latter into the recess of the bolt, and
at the same time disengages the tumblers. The lower tumblers have
also a spring, which bears against the same arm of the dog, and vibrates
the latter in the opposite direction, causing it to enter the notches of the
tumblers and to disengage the bolt when the said notches have been
brought into line by means of the key. If desired one of the tumblers
of the lower set may also be formed with a cam-like incline to act upon
the other arm of the dog simultaneously with the first incline.
The tumblers of the two sets are so arranged in respect to cach other
that the whole number of them overlap the keyhole, thus enabling all of

page_text: BEDDING Wwww.yo.
them to be operated simultaneously by a flat key, the construction of
which will be described hereafter.
The arrangement of the tumblers and the interior construction of the
lock may be variously modified without departing from the Invention ;
for instance, two sets of vibrating tumblers (operated simultaneously by
one key), one of which overlaps the other in such a manner that the two
scts occupy little if any more room than one.
•
The dog also, instead of being made in the form of a bell-crank lever,
may have two projections adapted to the notches of the tumblers.
Or the tumblers of the two sets as well as the dog may reciprocate
instead of vibrate, and the keyhole be at the bottom of the lock casc
directly beneath the bolt.
Or two reciprocating or vibrating dogs, adapted to notches on the
opposite sides of the bolt, may be used in connection with the two sets of
tumblers.
Or there may be three sets of reciprocating tumblers and a single dog.
These tumblers may be operated simultaneously by separate keys, or
by a single key described hereafter.
Or two sets of tumblers and a vibrating dog may operate in conjunc-
tion with a sliding bar to retain and release the swinging hasp of a
padlock.
:
Various other modifications suggest themselves; the different sets of
tumblers might (for instance) be arranged to operate simultaneously in
conjunction with a bolt without the intervention of a dog or dogs, and it
will be evident that the Invention can be applied not only to padlocks,
but to drawer and trunk locks, and to any key locks in which tumblers
arc employed.
It is essential however in carrying out this part of the Invention that
the tumblers should be operated directly by a key or keys to be simply
pushed into the lock without turning.
To simultaneously operate the two sets of tumblers above described I
use a flat key compactly constructed with a series of wards or projec-
tion and recesses at the end which are in the present instance arranged
in two continuous adjoining rows, and staggered in respect to each

page_text: of its arm against the edges of a single set of vibrating tumblers having
notches, which, when brought into line opposite the said arm of the dog
by means of a flat key, permit sufficient movement of the dog to free
the bolt or hasp, which then springs outward.
The notches of the tumblers, instead of being straight and coinciding
with the direction of the line of movement of the portion of the dog
adapted to them, so as to permit the latter to freely enter when brought
opposite the same as usual are inclined, so that when the notches are
first brought opposite the dog the latter enters the same to a slight
extent, but not sufficiently to free the bolt, it being necessary to continue
to move the tumblers by means of the key with the notches still in line
until the dog has gradually entered the same to its full extent, when the
said dog will have passed the shoulder of the bolt and the latter will
be free to shoot outwards.
It is evident that with this arrangement of the notches in respect to
the dog the difficulty of picking the lock will be much increased, for the
notches of the tumblers must not only be brought into line by the lock
picking instrument, but when brought into line they must be moved
simultaneously to a still greater extent before the lock can be opened.
When the bolt has been pushed inwards in order to lock the same, and
its recess and shoulder brought opposite the dog, the springs of the
tumblers tending to turn the latter, and being in the aggregate of greater
strength than the spring of the dog, causes the inclined edges of the
notches in the tumblers to act upon and automatically eject the dog
from the said notches, turning the same until it has fully entered the
recess above the shoulder of the bolt and freed the tumblers, which then
spring to another position.
Tumblers having inclined notches for the purposes above described
may be combined directly with a bolt or hasp, as well as with a dog and
bolt. They may also be used in locks provided with two or more distinct
sets of tumblers, such as already described, and are applicable in fact to
tumbler locks generally.
Upon the face of the bolt is a circular recess for the reception of a
seal, and directly over this recess an opening in the lock casing covered
by a glass plate, through which the seal can be seen, the object being to
arrange the seal so that it shall be positively defaced or destroyed if the

page_text: "
lock is opened, but so that it cannot be injured maliciously or by merely
tampering with the tumblers or other moving parts in attempting to pick
'the lock. The most certain way of effecting this object is to attach both
the seal and the defacing device to the sliding bolt, so that both move
with the same. Various devices may be used for defacing or destroying
the seal. In one arrangement a sliding rod is adapted to a recess in the
bolt and has a spring dog hung to it, which, when the bolt is shot
forward strikes a shoulder on the lock casing, and thus holds the rod,
and causes a projection of the same to traverse a slot in the bolt and to
tear or deface the seal immediately over the said slot. On the reverse
movement of the bolt the parts are restored to their original positions by
the striking of the end of the rod against the lock case and by a pin of
the bolt which lifts the dog.
Instead of the above a lever so hung to the bolt that when one arm
strikes a shoulder on the casing the other will be dragged through the
scal would answer the purpose well. Any form of scal may be
employed.
It is often desirable to remove the bolt from and replace it in the lock
casing without detaching the cap plate from the casing, this being
especially the case in locks of the character described, in which the cap
plate is rivetted fast.
: A retainer, which may be variously modified in form, is hung to a
projection of the lock case, and is so acted on by a portion of the
same spring which actuates the bolt as to be maintained in constant
⚫contact with the side of the latter. A hooked projection of the retainer
catches a corresponding projection-of-the-bolt, and thus determines the
extent of the outward movement of the latter, but by simply inserting
a rod through the key hole, and forcing the same against the retainer,
the latter may be pressed back from the bolt, which will then spring
entirely out of the lock case. The retainer has a bevilled upper edge, so
that it will yield and offer no obstruction to the reintroduction of the
bolt into the case.
The shoulder may be straight or inclined in the opposite direction if
desired, so as to enable the bolt to be pulled out of the casing by a slight
effort without necessitating the use of an instrument to be inserted
through the key hole.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Bristow Hunt in the Great Seal Patent Office
on the 19th February 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BRISTOW
HUNT, of Serle Street, Lincoln's Inn, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of August, in the year of our
Lord One thousand eight hundred and seventy-three, in the thirty-seventli
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Bristow Hunt, Her special licence that I, the
said Bristow Hunt, my executors, administrators, and assigns, or such
others as I, the said Bristow Hunt, 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, excrcise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN LOCKS AND KEYS," (a com-
munication to me from abroad by Daniel Klahr Miller and Allen
Middleton, junior, both of Philadelphia, Pennsylvania, United States of
America), upon the condition (amongst others) that I, the said Bristow
Hunt, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and scals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Scal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Bristow Hunt, do hereby declare the
nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement in writing, and on reference being had to the
accompanying Drawings, that is to say :-
The objects of this Invention are to produce a strong and compact
lock, to increase the difficulty of picking locks without unduly com-
plicating or increasing the cost of the same, to facilitate the construction
of keys for many tumblered locks, to prevent the destroying or defacing

page_text: of a seal by mere tampering with the lock, and to enable a bolt or hasp
to be readily withdrawn from and inserted into its place in a lock casing
without removing the cap plate from the latter.
In one form of the improved lock (which is illustrated in the side
views Figures 1 and 2 of the accompanying Drawings, which show the 5
working parts in different positions, and the cap plate removed) the
casc H is circular with a portion of one edge cut away to form a recess c,
across which slides a bolt or hasp F adapted to the interior of the case,
and hooked at its outer end or recessed at one side as shown at c¹ for
the reception of a staple, the latter being readily detached when the bolt 1
is thrust outward, as shown in Figure 2, but retained within a circular
opening formed by the two recesses c and c¹, when the said bolt is thrust
inward as seen in Figure 1.
When locked the bolt or hasp is contained almost entirely within and
protected by the casing, so that the difficulty of breaking or cutting the 1
same in order to detach the said staple is much greater than with the
exposed hasps of ordinary padlocks. In this form of lock two distinct
sets of vibrating spring tumblers A and B, hung to separate pins a and
a', and operated simultaneously by one key X inserted through a key-
hole X, are combined with a single bell-crank lever or dog D, theh ooked 20
arms b, b¹, of which, when the whole of the tumblers are properly
adjusted by the key enter notches d in the said tumblers, thus permitting
the dog to vibrate to a sufficient extent to release the bolt or hasp F,
which springs outwards from the case to the position shown in Figure 2
and releases the staple. When the bolt is pushed back into the case 25
the dog releases the tumblers, which spring to their original positions,
Figure 1, and at the same time the said dog enters a recess e in the side
of and retains the bolt.
One of the tumblers B¹ of the set B (see Figure 2) has a cam-like
inclinef, which, when the said tumbler is turned in the direction of the 30
arrow by a spring 9, acts upon the arm 6 of the dog D and forces the
latter into the recess e of the bolt, and at the same time disengages the
tumblers. The tumblers A have also a spring h, which bears against
the same arm 6 of the dog, and vibrates the latter in the opposite
direction, causing it to enter the notches of the tumblers and to 35
disengage the bolt when the said notches have been brought into line by
means of the key. If desired one of the tumblers of the set A may also

page_text: It is essential however in carrying out this part of the Invention, that
the tumblers should be operated directly by a key or keys to be simply
pushed into the lock without turning.
To simultaneously operate the two sets of tumblers illustrated in
Figures 1, 2, 3, 4, 5, and 7, the flat key X illustrated in the perspective
view, Figure 8, and end view, Figure 9, is used, the said key being com-
pactly constructed with a series of wards or projections and recesses a at
the end, which are in the present instance arranged in two continuous
adjoining rows, and staggered in respect to each other so as to produce
an appearance of irregularity in their arrangement. A key of this
character may also be used for simultaneously operating the nests of
tumblers illustrated in Figures 10, 11, and 12, which can scarcely be
considered as arranged in two sets, inasmuch as the whole number in
each case vibrate upon a single pin a.
To operate the three distinct sets of reciprocating tumblers shown in
Figure 6 a key constructed in accordance with the Invention, but
having an arm ? for operating the third set of tumblers, as shewn in the
perspective view, Figure 13, is employed. By bringing the lower ends
of the tumblers together however so that all should overhang a single
keyhole, the whole number in the three sets might be operated simul-
taneously by the modified form of key shown in the end view, Figure
14, where the projections and recesses a are arranged in three parallel
rows upon the end of the key.
For operating four sets of tumblers the projections and recesses a are
arranged in four rows as illustrated in the end view, Figure 15.
It is not absolutely necessary in carrying-out this part of the Invention.
that the projections a of the key should be arranged in continuous
parallel rows, as for some classes of locks they could be irregularly
arranged or staggered.
In some instances the projections or projections and recesses, might
be arranged upon one or both sides of the key, as seen in Figure 16,
instead of at the end.
In another form of lock (which is illustrated in Figures 17 to 22
inclusive) the main pecularities are,-
First., That it is provided with tumblers A having notches & so
inclined in respect to the direction of the movement of the arm 6 of the

page_text: dog or bolt adapted to the same, that in unlocking a continued simul-
taneous movement of the said tumblers will be required after their
notches have been brought opposite the bolt in order to permit the latter
to fully enter the said notches, so that in locking, the said inclined
notches shall serve as automatic ejectors to free the tumblers from the
dog or bolt.
And, Second. That both a seal Z and device; for defacing or destroying
the same are attached to, and caused to move with the bolt or hasp F,
as
shown in Figure 17, and in the transverse section, Figure 20.
And, Third. That a spring retainer G or equivalent device which will
permit the free introduction of the bolt into its place in the lock casing
but prevent its withdrawal until the retainer is itself pushed back, is
combined with the said bolt, as shown in the face view, Figure 22.
The general character of the lock is the same as those already
described, the sliding bolt or hasp T being acted on by a spring i
tending to force it outwards, which tendency is resisted by a bell-crank-
lever or dog D, adapted to a shoulder e on the bolt, and there retained
by the pressure of its arm 6 against the edges of a single set of
vibrating tumblers A having notches d, which when brought into
line opposite the said arm 6 of the dog by means of a flat key X permit
sufficient movement of the dog to free the bolt or hasp, which then
springs outward (see Figures 21 and 22).
It should be observed that the notches & of the tumblers instead of
being straight and coinciding with the direction of the line of move-
ment of the portion of the dog adapted to them, so as to permit the
latter to freely enter when brought opposite the same as usual, are
inclined as best observed in the enlarged views, Figures 18 and 19, so
that when the notches are first brought opposite the dog the latter
enters the same to a slight extent, as shown in Figures 18 and 21, but
not sufficiently to free the bolt, it being necessary to continue to move
the tumblers by means of the key with the notches still in line until
the dog has gradually entered the same to its full extent, as shown in
Figures 19 and 22, when the said dog will have passed the shoulder e
of the bolt, and the latter will be free to shoot outwards.
It is evident that with this arrangement of the notches in respect to
the dog the difficulty of picking the lock will be much increased, for

page_text: the notches of the tumblers must not only be brought into line. by the
lock picking instrument but when brought into line they must be
moved simultaneously to a still greater extent before the lock can be
opened.
When the bolt has been pushed inwards in order to lock the same,
and its recess and shoulder e brought opposite the dog the springs i of
the tumblers tending to turn the latter in 'the direction of the arrow
(Figure 21), and being in the aggregate of greater strength than the
spring of the dog, causes the inclined edges of the notches & in the
tumblers to act upon and automatically eject the dog from the said
notches, turning the same in the direction of the arrow (Figure 21)
until it has fully entered the recess above the shoulder e of the bolt
and freed the tumblers, which then spring to the position shown in
Figure 17.
Tumblers having inclined notches d, for the purposes above described,
may be combined directly with a bolt or hasp, as well as with a dog
and bolt. They may also be used in locks provided with two or more
distinct sets of tumblers, such as already described, and are applicable
in fact to tumblers locks generally.
Upon the face of the bolt F is a circular recess for the reception of
a seal Z, and directly over this recess and opening y in the lock casing,
covered by a glass plate, through which the seal can be seen; the object
being to arrange the seal so that it shall be positively defaced or
destroyed if the lock is opened, but so that it cannot be injured
maliciously or by merely tampering with the tumblers or other moving :
parts in attempting-to pick-the-lock. The most certain way of effecting
this object is to attach both the seal and the defacing device to the
sliding bolt, so that both shall move with the same. Various devices
may be used for defacing or destroying the seal. In Figure 20 a
sliding rod is adapted to a recess in the bolt, and has a spring dog t
hung to it, which when the bolt is shot forward in the direction of the
arrow strikes a shoulder m on the lock casing, and thus holds the rod k,
and causes a projection ¹ of the same to traverse a slot n in the bolt,
and to tear or deface the seal immediately over the said slot. On the
reverse movement of the bolt the parts are restored to their original 3
positions by the striking of the end of the rod k against the lock case,
and by a pin p of the bolt, which lifts the dog 1, as shown,
i

page_text: Instead of the above, a lever hung to the bolt, so that when one arm
strikes a shoulder on the casing the other will be dragged through the
scal would answer the purpose well. Any form of seal may be
employed.
It is often desirable to remove the bolt from and replace it in the lock
casing without detaching the cap. plate from the casing, this being
especially the case in locks of the character illustrated, in which the cap
plate is rivetted fast.
1
A. retainer G which may be variously modified in form is hung to a
projection of the lock case, and is so acted on by a portion of the same
spring i which actuates the bolt as to be maintained in constant contact
with the side of the latter. A. hooked projections of the retainer
catches a corresponding projection a' of the bolt, and thus determines
the extent of the outward movement of the latter, as shown in
Figure 22, but by simply inscrting a rod to through the keyhole, as
shown in Figure 22, and forcing the same against the retainer the latter
may be pressed back from the bolt which will then spring entirely out
of the lock case. The retainer has a bevilled upper edge so that it will
yield and offer no obstruction to the reintroduction of the bolt into the
case.
'
The shoulders and s¹ may be straight, or inclined in the opposite
direction, if desired, so as to enable the bolt to be pulled out of the
casing by a slight effort without necessitating the use of an instrument
to be inserted through the key hole.
Having now described the nature and object of the said Invention for
"Improvements in Locks and Keys," together with the manner in
which the same is to be or may be performed, or carried into practical
effect, I would remark in conclusion that I claim as the Invention com-
municated to me by the above-named Daniel Klahr Miller and Allen
Middleton, junior,-
First, In a lock, the combination, substantially as described of a
casing H having a recess c at one edge with a hooked or reccssed bolt or
hasp arranged to slide across said recess in the casing, as and for the
purpose specified (see Figures 1, 4, and 17).
Second. The bell-crank lover or dog D adapted to notches in the
edges of one or more sets of vibrating tumblers, and to a recess and

page_text: of the bolt into its place in the lock casing, but prevent the withdrawal
of the same until the said retainer is itself pushed back, all substantially
as specified.
In witness whereof, I, the said Bristow Hunt, have hereunto set my
hand and seal, this Eighteenth day of February, in the year of
our Lord One thousand eight hundred and seventy-four.