IMPROVEMENTS IN LOCKS AND LATCHES
Year: 1884

page_text: I JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of said Invention for "IMPROVEMENTS
IN LOCKS AND LATCHES a communication to me from abroad by Albert Louis
Becht of Paris in the Republic of France to be as follows:-
وو
-
This Invention consists in a novel construction and arrangement of the parts of
Locks as hereinafter described having for its object to prevent the obtaining of an
impression of the working parts of the Lock and also to prevent the picking of
the lock by ordinary means.
Means are also provided for locking the latch or catch and for detecting any
attempt to open the lock with any key but the proper one.
In carrying out this Invention the bolt (or a block of metal attached to the bolt)
is provided with a series of dovetailed recesses engaging with projections on the
tumblers and each tumbler is provided with two projections capable of engaging
with the said recesses. The surfaces of these projections are preferably roughened
or serrated to prevent slipping and the projections are situated on opposite sides of
the centre pin on which the tumblers turn-Springs attached at one extremity to
the tumblers and bearing at the other extremity against a fixed stud cause the
projections at the hinder ends of the tumblers to engage with the corresponding
recesses of the bolt the extent of the movement being limited by a stop. The
projections on the tumblers are of various lengths but the notches or surfaces on
the opposite sides or edges of the said tumblers and acted on by the bitt of the
key are all equal. This arrangement renders it impossible to obtain an impression
by means of keys with moveable bitts or otherwise the tumblers being moveable
and not presenting relatively to one another any projection capable of producing
an impression.
In order to move the bolt all the unequal projections on both ends of, the
tumblers have to be brought into one plane so as to clear the sides of the recesses
in the bolt. This is effected by the action of the bitt of the key which is provided
with steps corresponding with the length of the said projections.
When the bolt has been shot by the key the latter ceases to act upon the
tumblers which then engage with one of the dovetailed recesses of the bolt,

page_text: When the bolt has been drawn back the key may be arranged to act upon a
device connected with a latch and consisting of a moveable plate connected to the
latch and to an oscillating arm turning on a pin on the bolt the said arm being
provided at its free extremity with a projection or tongue which when the bolt is
drawn back is brought opposite the front ends of the tumblers so that the latch
cannot be drawn back unless recesses provided in different positions in the ends of
the tumblers are all elevated by a partial rotation of the proper key acting upon
suitable surfaces provided on the said tumbers, to the level of the projection on the
oscillating arm. The projections are then enabled to enter the recesses and allow
the latch to be drawn back by the action of the key or otherwise.
A detector arrangement may be advantageously combined with the lock the said
detector arrangement being of great delicacy. For this purpose the tumblers are
provided with additional differential projections preferably at the rear end in such
a manner that if an attempt be made to unfasten the lock with any key but the
right one these projections being moved beyond the limits to which they would be
moved by the bitt of the proper key push down a slider provided with or connected
to a catch inclined or bevelled on one side. This catch when the slider is operated
as hereinbefore described engages with a notch in the edge of the bolt in such a
manner that the bolt cannot be drawn back even with the proper key when applied
in the usual manner. To unfasten the lock with the proper key under these
conditions the key must be turned the wrong way at first so that the notch in the
edge of the bolt may act upon the inclined side of the catch connected to the slider
and push it back to its normal position in which it is retained by a spring engaging
with notches in the side of the slider.
The improved arrangements herein before described are applicable to all descrip-
tions of locks and to padlocks with spring bolts or otherwise.

page_text: I JOHN HENRY JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention for "IMPROVEMENTS IN
LOCKS AND LATCHES" which Invention has been communicated to me from abroad:
by Albert Louis Becht of Paris in the Republic of France and in what manner
the same is to be performed to be particularly described in and by the following
statement:-
This Invention consists in a novel construction and arrangement of the parts of
locks and latches as hereinafter described having for its object preventing the
obtaining of an impression of the working parts of the lock and also to prevent
the picking of the lock by ordinary means. Means are also provided for locking
the latch and for detecting any attempt to open the lock with any key but the
proper one.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying drawings represents a lock constructed according
to this Invention in elevation the cap plate being removed in order to show the
internal arrangement. P is the bolt to which is attached a block A presenting a
series of dovetailed recesses marked x x x² and y y¹—The recesses o x1 x²
correspond or are capable of engaging with corresponding projections a formed
upon tumblers S turning on a fixed pin or axis O when operated by the key
(indicated at 2) and the recesses y y¹ are capable of engaging with projections b
formed on the same tumblers but situated on the opposite side of the pin or
axis O-The surfaces of the projections a and b are preferably roughened or
serrated on both sides as shewn in the drawing and the surfaces of the recesses in
the block A are provided with corresponding notches & affording a firm hold for
the serrations on the projections a and b.
In figure 1 the block is represented with the parts in the position which they
occupy when the bolt has been shot twice or double locked. When in this position
the projections a on the tumblers S. engage with the recess in the block A.
Springs attached at one extremity to the tumblers S and bearing at the other
extremity against a fixed stud t cause the projections a at the hinder ends of the
tumblers to engage with the corresponding recesses when not operated by the key
the extent of the movement being limited by a stop 9 The projections a and b on
the tumblers S are of various lengths and the under sides or bellies of the tumblers S
present suitable notches or curved surfaces m m' at the part where the bitt of the
key acts upon the said tumblers-All these notches or curved surfaces are equal or
of the same form relatively to the bodies of the tumblers this being a contrary
arrangement to that ordinarily employed in locks of this class-This arrangement
renders it impossible to obtain an impression by means of keys with movable bitts
or otherwise the tumblers S being movable and not presenting relatively to one
another any projection capable of producing an impression which would indicate
the combination necessary to liberate the bolt.
In order to move the bolt it is necessary to cause all the projections a and b
(which are of unequal length) to coincide that is to say to bring the upper surfaces
thereof into one plane so as to clear the under side of the block A-This is effected
by the action of the bitt of the key which is provided with steps corresponding
with the length of the said projections and so arranged that when the key is turned

page_text: i
it lifts the tumblers in such a manner as to move all the unequal projections a
and bout of the recesses in the block A as indicated by the thick dotted lines in
figure 1 and thus disengage the bolts.
Figure 2 is a transverse section (taken along the line 1-2 figure 1) of the bolt
and tumblers showing the projections a in dotted lines engaging with one of the
said recesses and Figure 3 is a similar view showing the tumblers lifted by the key
80 as to disengage the bolt-These two figures also show the steps on the key
which are arranged to correspond with the unequal projections a and b on the
tumblers so that when the key is in the position indicated in figure 3 (and by the
dotted line in figure 1) the projections a are moved out of the corresponding recess
at one extremity of the block A without lifting the opposite extremities of the
tumblers sufficiently to cause the projections b to engage with the recesses at the
other extremity of the said block.
The lock may be so arranged that when the bolt has been drawn back the key
acts upon a device connected with a latch 7 and consisting of a movable plate
or lever M pivotted at i connected to the latch and to an oscillating arm w turning
on a pin D on the bolt the said arm being provided at its free extremity with a
projection or tongue n which comes in contact with the ends S¹ of the tumblers
when the bolt is drawn back so that the latch cannot be drawn back unless
recesses figure 1 provided in different positions in the ends S₁ of the tumblers S
are all elevated by a partial rotation of the proper key acting upon the bellies m of
the said tumblers to the level of the projection n-When all the recesses u are thus
placed in a line with the projection n the latch is free to be drawn back by the
action of the key or by pulling a ring or handle connected to the latch-The
object of this arrangement is to prevent the latch being drawn back except by
means of the proper key but it is not essential to the working of the improved
lock When this arrangement is employed a false tumbler or filling piece or
plate A¹ is placed at the back of the tumblers S in order to enable the plate M to
pass between the ends S¹ of the said tumblers and the side of the bolt P-A guard
plate L is placed over the shank of the latch in order to render it impossible to
move the latter by means of a pick introduced through the key hole.
A. detector arrangement may be advantageously combined with the lock
constructed as hereinbefore described-A very efficient mode of obtaining this
result consists in providing the tumblers S with projections of unequal length and
preferably arranged at the rear end of the said tumblers as indicated at c Figure 1
in such a manner that if an attempt be made to unfasten the lock with any key
but the right one these projections being moved beyond the limits to which they
would be moved by the bitt of the proper key come in contact with a projection f
on a sliding plate p and thereby push down the said plate.-The upper extremity
of this plate is provided with or connected to a catch g inclined or bevelled on one
side This catch when the sliding plate p is operated as herein before described
engages with one of three notches g¹ (shown in dotted lines in figure 1) in the
upper edge of the bolt and locks the latter in such a manner that it cannot be
drawn back even with the proper key when applied in the usual manner-To
unfasten the lock with the proper key under these conditions the key must be
turned the wrong way at first so that the notch in the edge of the bolt may act
upon the inclined side of the catch g and push it back to its normal position in
which it is retained by a spring engaging with a notch 22 in the side of the
sliding plate p-This spring also serves to retain the detector in the locked position
by engaging with a notch 3 arranged above the notch ².
The improved arrangements hereinbefore described are applicable to all descrip-
tions of locks and padlocks with spring bolts or otherwise.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is..
1st In the construction of locks the employment of tumblers presenting unequal
projections corresponding with steps in the bitt of the key and situated on the
5

page_text: opposite side or edge of the said tumblers to that acted on by the key as and for
the purpose substantially as herein before described and illustrated in the accom-
panying drawings.
2nd In the construction of locks and latches the employment of tumblers
presenting recesses arranged in different positions relatively to the bodies of the
tumblers for the purpose of locking the latch as hereinbefore described and
illustrated in the accompanying drawings.
3rd In the construction of locks the employment of a detector arrangement
wherein unequal projections on the tumblers are caused to come in contact with
and operate a detector or catch whenever an attempt is made to unfasten the lock
with any key but the proper key substantially as hereinbefore described and
illustrated in the accompanying drawings.
4th The combination and arrangement of parts constituting the improved lock
and latch hereinbefore described with reference to the accompanying drawings.
Dated this 30th day of October 1884.
J. HENRY JOHNSON.