IMPROVE- MENTS IN LOCKS
Year: 1854

page_text: LETTERS PATENT to Robert McConnel, of Glasgow, in the County of
Lanark, North Britain, Iron Founder, for the Invention of "IMPROVE-
MENTS IN LOCKS."
Sealed the 13th March 1855, and dated the 25th September 1854.
PROVISIONAL SPECIFICATION left by the said Robert McConnel at
the Office of the Commissioners of Patents, with his Petition, on the
25th September 1854.
I, ROBERT MCCONNEL, of Glasgow, in the County of Lanark, North
Britain, Iron Founder, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN LOCKS" to be as follows:-
This Invention relates to a new construction of lock whereby increased
security is obtainable, and to a new contrivance for moving door latches, by
means of which a greater certainty of action is secured. The improved lock
is so constructed, that when the bolt is shot and the key removed, it cannot
be shot back without first being moved a short distance further out. The
bolt and tumblers and the key are so constructed, that this double motion
of the bolt is effected in the regular course by turning the key in one
direction only, as in ordinary locks. In moving the bolt when unlocking,
the key first acts on an incline formed upon the under side of the bolt, in
such a manner as to force the bolt outwards, although the key is itself
turning in the other direction. On continuing to turn the key, the bolt

page_text: after being moved outwards returns, and is shot back into the lock in the
ordinary manner. The bolt carries the usual stump, which works in the open-
ings made in the tumblers, these openings being formed to suit the peculiar
motion of the bolt. The first action of the key upon the tumblers is to
slightly raise as many of them as are necessary, in order to bring the stump
exactly opposite a short passage directed outwards; the stump then moves
outwards until it reaches a passage formed in the tumblers at right angles, or
nearly so, to the bolt, and the tumblers are raised to allow the stump to
pass down this passage. The raising of the tumblers brings the stump oppo-
site a passage which is parallel with the bolt, and along which the stump
passes whilst the bolt is being shot completely back into the lock. Finally,
the tumblers fall slightly, and the stump remains in a recess on one side of the
passage last mentioned. It follows hence that the stump moves in four
different directions as regards the tumblers; and notches being formed at the
several points where the change in the direction takes place, the chances
against getting the tumblers into the proper positions for moving the bolt,
these positions also having to be different at different stages of the operation,
are considerably increased. Increased variety and complexity is given to the
movements of the tumblers by forming irregular notches on them, where
the key acts upon them, in such a manner that they are moved by the side
of the key, instead of, or as well as, by the point, and the acting surface of
the side has consequently to be accurately formed relative to the centre of
motion of the key. The key is also constructed in a novel manner, and with a
view of obtaining greater security, namely, with the point, which acts on the
bolt and on the several tumblers, set apart from each other, being bent, as it
were, to different sides and in different degrees. The pin upon which the key
barrel is entered, is made oval, or is flattened or grooved at one side, and one
or more pins are fixed to the key barrel, being made to project inwards, so that
on turning the key when in the lock it may in certain positions be forced to
one side by the action of the pin inside the barrel on the full side of the fixed
pin or pipe piece, and notches or grooves may be cut in this last piece to suit
the pins in the key barrel. The security of the lock is also further enhanced
by the application of a moveable shield to the key-hole. This shield is formed
with a central opening through which the shank of the key can pass, and with
two openings through which the bit of the key can pass, these of course
communicating with the central opening. The shield oscillates upon a pin
above the key-hole, and at its back carries a pin, which prevents one or more
of the tumblers from moving when either of the bit openings in the shield are
opposite the outer key-hole. The shank of the key is provided with a pin,

page_text: which acts on the shield plate, so as to turn it to the position proper for
releasing the tumblers after the key is introduced. In constructing door
latches according to this Invention the ordinary "follow" is dispensed with,
and the handle spindle is fixed to the short arm of the crank lever, which
moves the bolt. The spindle works in a short slot in the side or sides of the
latch box, and is moved either by depressing it or by turning it, the turning
action having almost the same effect as depression, on account of the spindle
being fixed to the lever very near the centre of oscillation.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert McConnel in the Great Seal Patent Office on the
23rd March 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
MCCONNEL, of Glasgow, in the County of Lanark, North Britain, Iron
Founder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of September, in the year of our
Lord One thousand eight hundred and fifty-four, in the eighteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Robert McConnel, Her special license that I, the said Robert
McConnel, my executors, administrators, and assigns, or such others as I, the
said Robert McConnel, my executors, administrators, or assigns, should at
any time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN LOCKS," upon the condition (amongst others) that I, the said Robert
McConnel, by an instrument in writing under my hand and seal, should par-
ticularly 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 Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert McConnel, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say:-

page_text: My said Invention relates to a new construction of lock whereby increased
security is obtainable, and to a new contrivance for moving door latches, by
means of which a greater certainty of action is secured. The improved lock
is so constructed, that when the bolt is shot and the key removed, it cannot be
shot back without first being moved a short distance further out. The bolt
and tumblers and the key are so constructed that this double motion of the
bolt is effected in the regular course by turning the key in one direction only,
as in ordinary locks. In moving the bolt when unlocking, the key first acts
on an incline formed upon the under side of the bolt, in such a manner as to
force the bolt outwards, although the key is itself turning in the other direc-
tion. On continuing to turn the key, the bolt after being moved outwards
returns, and is shot back into the lock in the ordinary manner.
The bolt
carries the usual stump, which works in the openings made in the tumblers,
these openings being formed to suit tho peculiar motion of the bolt. The
first action of the key on the tumblers is to slightly raise as many of them as
are necessary, in order to bring the stump exactly opposite a short passage
directed outwards; the stump then moves outwards until it reaches a passage
formed in the tumblers at right angles, or nearly so, to the bolt, and the
tumblers are raised to allow the stump to pass down this passage.
The
raising of the tumblers brings the stump opposite a passage which is parallel
with the bolt, and along which the stump passes whilst the bolt is being shot
back into the lock. Finally, the tumblers fall slightly, and the stump remains
in a recess on one side of the passage last mentioned. It follows hence that
the stump moves in four different directions as regards the tumblers; and
notches being formed at the several points where the change in the direction
takes place, the chances against getting the tumblers into the proper positions
for moving the bolt, these positions also having to be different at different
stages of the operation, are considerably increased. Increased variety and
complexity is given to the movements of the tumblers by forming irregular
notches on them, where the key acts upon them, in such a manner that they
are moved by the side of the key, instead of, or as well as, by the point, and the
acting surface of the side has consequently to be accurately formed relative to
the centre of motion of the key. The key is also constructed in a novel manner,
and with a view of obtaining greater security, namely, with the points, which act
on the bolt and on the several tumblers, set apart from each other, being bent,
as it were, to different sides and in different degrees. The pin upon which the
key barrel is entered is made oval, or is flattened or grooved at one side, and
one or more pins are fixed to the key barrel, being made to project inwards,
so that on turning the key when in the lock, the pin may in certain positions

page_text: be forced to one side or turned by the action of the pin inside the barrel on
the full side of the pin or pipe piece, and notches or grooves may be cut
on this last piece to suit the pins in the key barrel. The security of the lock
is also further enhanced by the application of a moveable shield to the key-
hole. This shield is formed with a central opening through which the shank
of the key can pass, and with two openings through which the bit of the key
can pass, these of course communicating with the central opening. The shield
oscillates upon a pin above the key-hole, and at its back carries a pin; which
prevents one or more of the tumblers from moving when either of the bit
openings in the shield are opposite the outer key-hole. The shank of the key
is provided with a pin which acts on the shield plate, so as to turn it to the
position proper for releasing the tumblers after the key is introduced. In
constructing door latches according to this Invention the ordinary "follow"
is dispensed with, and the handle spindle is fixed to the short arm of tlie crank
lever, which moves the bolt. The spindle works in a short slot in the side or
sides of the latch box, and is moved either by depressing it or by turning it,
the turning action having almost the same effect as depression, on account
of the spindle being fixed to the lever very near the centre of oscillation.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several explanatory Figures on the two Sheets of
Drawings hereunto attached.
end view,
Figures 1, 2, 3, and 4, on Sheet.1 of the Drawings, are inside views of a
lock as constructed according to my improved 'system. Figure 1 is designed
to illustrate the action of the bolt; Figure 2, the action of the tumblers; and
Figure 3, the action of the key-hole shield; whilst Figure 4 shews an addi-
tional contrivance in connection with the pin, and lying beneath the bolt,
which is supposed to be removed in this Figure. Figure 5, on the same
Sheet of Drawings, is an elevation of the key; and Figure 6 is an
corresponding; Figure 7 is an elevation of a loose tubular pin piece, which is
fitted upon the fixed piu of the lock, as will be herein-after more particularly
described. Figure 8, on Sheet 2 of the 'Drawings, is' an inside view of a
latch lock as constructed according to my Invention. Figure 9, on the same
Sheet of Drawings, represents another modification of latch constructed
according to the same system. Figure 10 is an elevation, and Figure 11 is a
transverse section, through the bit of a key constructed for a lock similar to
that represented in Figures 1, 2, 3, and 4, on Sheet 1 of the Drawings, this
key being contrived so as to greatly increase the difficulty of making a dupli-
cate of it: The box A of the lock is constructed in the usual manner, and
the bolt B, which is represented as locked, is slotted at C, to slide upon the

page_text: guide pins D, fixed to the case A of the lock. The pin of the lock upon
which the key turns is at E. The key F is represented in Figure 1 as
sectioned just above the lowest tongue G of the bit, this tongue being the one
which moves the bolt B. In Figure 1 the key is represented as just about to
act on the bolt for the purpose of unlocking it. The point of the tongue G
first acts on the inclined edge II of the bolt, this edge being of such a shape
as to cause the bolt to be forced outwards as far as the line I when the key is
turned. The key then turns onwards in the direction of the arrow until the
tongue G comes in contact with the back side J of the notch in the lower
edge of the bolt B, when it shoots back the bolt to the line K, that is to say,
completely into the lock. The bolt is pressed inwards a short distance from
its outermost position by a lever L, actuated by a blade spring M, and it is
furnished with the usual stump N, which projects through the openings in the
tumblers. In Figure 2, one of the tumblers O is represented as placed over
the bolt B: of course any number of tumblers may be employed, but it will
be unnecessary to describe the action of more than one, as the practical lock-
smith will be able to vary the patterns of the several tumblers and of the
corresponding parts of the key to fit them, as is done in ordinary tumbler
locks. The portion of the lower edge of the tumbler which is acted upon
by the key is formed with a projecting piece P, which is thinner than the
main body of the tumbler; and the key is correspondingly formed with a deep
groove as at Q, Figure 5, into which the thin pieces P enters, and is acted
upon by the points of the solid metal of the key-bit within the recess or groove,
an arrangement which considerably increases the difficulty of making a dupli-
catc key. In Figure 2 the key is represented as about to act on the tumbler O,
so as to move it for the purpose of unlocking the bolt. The tumbler is first
raised so as to enable the stump N to pass outwards at R, notches and pro-
jections being provided to catch the stump if the tumbler is not moved into
the precise position required. The bolt carries the stump N as far outwards
as to bring it immediately opposite the vertical passage S in the tumbler.
If it moves too far, or not far enough, it will be caught as before. The
tumbler is next raised until the stump N is opposite the horizontal passage T,
and the same accuracy of action is required to enable the stump to enter this
passage. The bolt is then shot into the lock, and carries the stump N along
the passage T, this passage being shaped so as to require various movements of
the tumbler to prevent the stump from being caught by projections or notches
as it passes along to the point U, where it remains as long as the bolt is
unlocked. The earlier movements of the tumbler are produced by the action
of the key on the thin piece P, after which the projecting point V of the key

page_text: bit acts on the curved edge W of the tumbler, and produces the latter portion
of the tumbler's movements, the reaction of the tumbler in each case being
effected by the blade spring X in the usual manner. The tumbler O is formed
with certain notches at Y on its upper edge, which are contrived in connection
with a shield Z, represented in Figure 3. This shield is placed outside all the
internal mechanism of the lock, and oscillates on a pivot at a, above the level
of the key-hole. It is formed with an opening 6 to admit the key, this open-
ing having two radiating portions c, corresponding to the bit of the key. In
Figure 3 the shield is represented in the position in which it is when the key
is introduced for unlocking. In this position, a projection on the back of the
shield, indicated by dotted lines at d, prevents the tumbler O from rising.
When the key is introduced and turned, it turns the shield by means of a
projection on the under side of the latter, so as to bring the portion e over the
lower portion of the key-hole, and at the same time releases the tumbler.
After moving the bolt the key turns the shield, so as to obtain egress at the
other aperture c, and this movement of the shield again locks the tumblers.
Thus, when there is an open passage into the lock, and it is consequently easier
to introduce a lock-picking instrument, the tumblers are held stationary, and
they can only be moved when the key-hole is entirely closed, with the excep-
tion of the small annular space corresponding to the barrel of the key. The
shield is held in its several positions by a pin f, projecting up from beneath,
and fixed upon a lever g, acted upon by a spring h. as is shewn in Figure 1.
The pin fenters notches in the shield, and is shifted out of them at the proper
times by the action of the key on the lever g. The fixed pin E, upon which
the key turns, has fitted upon it a tubular piece i, made to suit the peculiar
internal construction of the key barrel, and also adding to the security of the
lock by acting on an additional stump tumbler j, Figure 4, placed below or
behind the bolt. I call this tumbler a "stump" tumbler, because, instead of
acting like ordinary tumblers upon a stump fixed upon the bolt, it carries
a stump itself, which works in an irregular opening 7, Figure 1, in the
The tubular piece i is formed with an inclined groove m, which
communicates with a comparatively wide opening n. Inside the barrel of the
key are fixed three pins o, projecting inwards, as indicated by dotted lines
in Figure 5, and on passing the key into the lock these pins enter the
groove m, and turn round the piece i to a certain extent before the key itself
is turned at all. This brings the pins o into the space n, and when the key
turns, the pins act on either side of the opening n, and carry round the
piece i along with the key. On the inner end of the tubular piece i is a small
disc P₁ formed with points q, r. &, which act on the stump tumbler j. When
bolt.

page_text: the bolt is locked the tumbler jis raised, but on unlocking, the point 7 is
brought against the point t of the tumbler, and throws it down, bringing the
stump into the position represented in Figure 1. After this the point
comes round, and, acting on the point of the tumbler j, raises it, so that the
stump enters the passage in the bolt whilst the bolt is moving into the
lock. The point s then gradually raises the tumbler j, so that the stump k
passes up the inclined passage w.in the bolt, whilst the bolt moves to its inmost
position in the lock. If from any cause the spring M and lever I should not
be able to force the bolt fully back, the stump will effect this by its action on
the upper side of the inclined passage w. All the movements of the tumbler j
obviously require to take place at certain precise periods, corresponding to the
movements of the other parts of the lock; consequently great accuracy is
required in fixing the points 9, r, s, and in forming the opening n in a position
corresponding to that of the points o in the key barrel, whilst greatly increased
difficulty is thrown in the way of the unlocking action of any instrument but
the true key, by the narrow inclined groove m, through which the points o in
the key barrel have first to pass before they can be brought into a position
for: turning the tubular piece i and points q, r, s, in a proper manner. In
locking the bolt, the reverse movements of those herein-before described take
place. The key représented in Figure 10 and 11, on Sheet 2 of the Drawings,
is of a description suitable for the kind of lock herein-before described.
constructed with a view of throwing great difficulties in the way of a fradulent
person desirous of obtaining a duplicate key by taking a cast of the true key.
For this purpose the projecting portions of the key-bit, such as A, are made
to overlap, whilst other portions, as at B, are made with internal hollows, so
that if any material were applied to the key to obtain an impression' or 'mould
of it, portions of that material would necessarily be retained in the recesses;
whilst at the same time the obtaining. a correct impression of these internal
points is of the more importance, as it is by them that a portion of the move-
ments of the lock are effected, as. herein-before described. In my improved
latch lock, as represented in Figure 8, on Sheet 2 of my Drawings, the
handle A is fixed to the short arm B of the cranked lever C, which moves the
latch bolt D. The cranked lever C works on a centre at E, and is jointed to
the bolt at F. The short arm B passes out through a slot in the side G of
the latch box, and a spindle is fixed to it; upon which one or two handles are
fixed, accordingly as the spindle is or is not passed completely through the
door. A simpler arrangement of latch is represented in Figure 9, also on Sheet
Two of the Drawings. Here the bolt A forms the extremity of, and is fixed
at right angles to, a comparatively long lever B, which turns on a centre at C,
It is

page_text: and has a short arm D fixed to it, to which last tho handle or thumb piece E
is fixed. The bolt is closed by a spring F, acting on a short projection on the
eye of the lever B, and the bolt is represented as shut, that is to say, as
projecting from the.plate G, which is fitted flush with the edge of the door.
Having now, described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe, in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my Invention; but what I
consider to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent, is,
First, the general arrangement and construction of locks, as herein-before
described.
Second, the system or mode of arranging the mechanism of locks, so that
on unlocking them the bolt is first moved outwards a short distance before
being shot or actually passed into the lock, as herein-before described.
Third, the system or mode of constructing the tumblers of locks, as more
particularly described in reference to Figure 2, on Sheet 1 of the Drawings
hereunto attached.
Fourth, the application and use in locks of a shield which covers the "bit"
part of the key-hole when the tumblers are free to move, and prevents the
movement of the tumblers as long as the key-hole is fully open, as more
particularly described in reference to Figure 3, on Sheet 1 of the Drawings
hereunto attached.
Fifth, the system or mode of constructing lock keys with pins or points
inside the barrel, such pins or points being contrived to act on the pin of the
lock or on a moveable piece upon the pin, such moveable piece being made to
act on an additional tumbler or catch in connection with the bolt, as more
particularly described in reference to Figures 4, 5, 6, and 7, on Sheet 1 of the
Drawings hereunto attached.
Sixth, the system or mode of constructing lock keys with the several
portions of the bit radiating or projecting in different directions from the
barrel, as herein-before described.
Seventh, the system or mode of constructing lock keys with overlapping.
projections and-internal hollows in the "bit" portion, as more particularly
described in reference to Figures 10 and 11, on Sheet 2 of the Drawings
hereunto attached.

page_text: Eighth, the system or mode of constructing latch locks, as more particularly
described in reference to Figures 8 and 9, on Sheet 2 of the Drawings hereunto
attached.
•
In witness whereof, I, the said Robert McConnel, have hereunto set my
hand and seal, this Twenty-second day of March, in the year of our
Lord One thousand eight hundred and fifty-five.
ROBERT M'CONNEL. (L.S.)