Improvements in Locks for Safes.
Year: 1888

page_text: Date of Application, 18th Dec., 1888
Complete Specification Left. 11th Sept.. 1889-Accepted. 18th Dec., 1889
PROVISIONAL SPECIFICATION.
Improvements in Locks for Safes.
I, STUART CARADOC MUNRO, of No. 1 Long Wynd, Dundee, in the County of
Forfar, North Britain, Gentleman, do hereby declare the nature of this invention to
be as follows:
My invention relates to improvements in locks for safes described in the specifica-
tion of my Letters Patent No. 6145, A.D. 1887, and has reference to the small
pinions on which the studs were mounted, to the discs carrying the dials, to the dials,
to the index gearing with the above pinions, and to the upper disc.
My invention comprises also an improved finger bar of peculiar shape for opposing
the upward passage of the tilting plate.
In carrying my invention into practice, and with reference to the above men-
tioned pinions, I fix a collar to the indices which are mounted upon a cylindrical
spindle and form, upon the inner sides of this collar, teeth enabling such collar
to gear with the said pinions. I further fix, to the underside of the index proper,
a pin which will be made to enter one of twenty holes formed in a disc placed
above the said pinion, and I further make the spindle of the index square, to enter
and fit a central square hole in the disc, or I fix it with screws or otherwise. The
latter disc is cut or notched excentrically on its underside, so as to form a lip
taking the place of the pointer described in the specification before mentioned. The
object of this arrangement is to maintain the tilting plate in a horizontal position
so as to avoid detection by moving the indices.
I further provide the upper disc with teeth and I adopt an additional metallic
bar furnished with spring fingers and acting in conjunction therewith to further
prevent detection. The notches surrounding the dial are made vertical, to allow the
owner to open the safe in the dark. In case the number had been forgotten and the
shutter could not be opened, the same would have to be forced, and for this reason I
provide an additional shutter to replace the former.
I also use a solid cast metallic piece of peculiar shape provided with a spring and
having a cam or catch which opposes the npward passage of the tilting plate but
yields when it is depressed.
.
By using this piece there is no further necessity to have recourse to a bell.
Datad this 18th day of December 1888.
HUGHES, ELI & HUGHES,
76 Chancery Lane, London, W.C., Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in Locks for Safes.
I, STUART CARADOO MUNRO, of No. 1 Long Wynd Dundee, in the County of
Forfar, North Britain, Gentleman, do hereby declare the nature of this Invention, and
in what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, that is to say :-
This Invention relates to improvements in locks for safes, for which previous
Letters Patent were granted to me No. 6145, A.D. 1887, in the Specification of
which I described certain mechanism whereby a shutter closing the keyhole of the
lock could be retained in position opposite the said keyhole, until liberated by a
person conversant with the working of such mechanism.
In order that the present invention may be fully understood, I have hereunto
annexed drawings of the door of a safe constructed in accordance therewith.
Fig. 1 is an elevation of the interior mechanism of the door of the safe as seen
from the inside and Fig. 2 is a plan thereof.

page_text: Fig. 3 is a sectional side elevation of the mechanism taken through 1-2, Fig. 1
and Fig. 4 is a similar section taken through 3-4 in the same Figure.
Fig. 5 is a detail of the rocking bar and disc with parts connected therewith, the
disc itself being shown in further detail in Figs. 6 and 7.
Fig. 8 is a front view of the safe, and the same letters refer to the same parts in
all the various views or figures.
The shutter A which closes the keyhole. (see Fig. 8) is provided with a re-
taining catch B, notched at its inner end, the notch engaging with a rim formed
on a bolt B which is capable of having a circular motion imparted to it around
its axes b. A stud ¹, fixed in the bolt, enters and works within a slot formed
in a bar C which forms part of the frame C¹, the said frame being capable (in
this case) of having a vertical reciprocatory or rising and falling motion imparted
to it by means of a handle which operates a curved lover C, anti-friction
rollers e, being provided for the levers to bear against. As described in the Speci-
fication of my foriner patent the opening of the shutter A is dependent on the
movement of the frame (", and can only take place when such frame has travelled
to the full extent of the slots a. At the same time the two arms C4 fixed one at
each end of the frame C¹ must pass under the studs or pins which project
from each end of the said rocking bar (the T pieces fixed to the frame passing
also underneath the rocking bar D) and this the said arms can only do when the
locking devices are arranged in a certain manner, such arrangement being effected,
as heretofore, by means of index fingers or pointers on the outer side of the door.
From what I have already stated, it will be observed that the general principle of
the Invention is similar to that of my former one; the locking mechanism however
possesses many features of novelty, and I will now proceed to describe the same in
detail.
The rocking bar D is pivotted at each end in bearings e and carries, as before
stated, projecting pins c¹, c². As the mechanism at each end of the bar is alike the
description of one end will suffice. In order that the arm C may pass the pins c³, c³,
the pin must ride on the incline e', and this can only take place when the rocking
bar D is free to tilt on its axis e. The tilting of the bar D is dependent on the
position of the discs F, details of which are shewn in Figs. 6 and 7. The disc F
consists of a hollow shell, the rim or flange f of which is cut away for a certain
portion of the circumference on each side. The discs are mounted on sleeves F¹, and
unless placed in one particular position, the rim f will bear on each side of the
bar D in this position the bar D cannot tilt. If however the disc be so placed
that the cut away portions of the rim terminate slightly beyond the lower edge of
the bar, the latter will be free to tilt as shown in Fig. 5. Presuming that the discs
have been properly adjusted by means of the fingers or pointers on the index plates
or dials the person opening the safe will next turn the handle C* and in so doing
will raise the frame C¹. The first movement of the frame will cause the inclines e¹ to
come in contact with the pins on the ends of the bar D and this bar being free
to tilt will do so and allow the frame C³, pieces T and arms to travel to the full
extent of the slots a which will effect the release of the catch B. On the return
movement the vertical end of the incline e' will engage with the pin and the bar D
will then be rigid, owing to the disturbance in the position of the discs F which
results from the pieces T passing between the obstructing fingers G which are fixed
on the sleeves F¹, on which the discs F are mounted. In passing between the
fingers G necessarily turn the discs F round, and in so doing cause the rim f to bear
on each side of the bar D whereby, as before stated it is prevented from tilting. In
order to allow the arms C to return, the incline or catch e¹ is free to revolve on the
pivote and so pass underneath the pin c³, after which it is returned to its normal
position by the flat spring e.
The actual locking and unlocking of the shutter A being understood, the next point
to consider is the combination of devices for preventing the mechanism from being
tampered with. The key to any ordinary permutation lock can generally be dis-
covered by a process of "feeling," that is to say, handling each part separately and

page_text: noticing slight irregularities of movement, by which method a proper adjustment of
the parts may eventually be arrived at. To defeat such attempts, the arm C is pro-
vided with
tappit which upon the first movement of the said arm rides on and
depresses the inclined end of a bent lever G, causing the latter to turn on its axis,
such axis being a continuation of a rocking bar H from which project arms carrying
check springs h, shaped somewhat like the anchor of an escapement wheel. As the
bar H turns on its axis, the springs are depressed, and engage immediately with the
teeth of the wheels J, which are mounted on the sleeves F, and so prevent the wheels,
and consequently the discs, from being turned round. The engagement of the
springs with the wheels J, occurs when the discs F are properly adjusted for
opening, but it will be observed that the pieces T, having some distance to travel,
before coming into contact with the fingers G, sufficient time is allowed for the
tappit ct to pass over the inclined end of the lever G', and beyond the axis or centre
thereof, after which it begins to bear on the part G' of the said lever, and depresses
the same, thus disengaging the springs h, and leaving the wheels J and discs F free
to revolve under the pressure of the pieces T. The bar H is subjected to the action
of the tappit c on the return or locking motion of the mechanism but is brought to its
normal position by the downwardly bent end of the arm C*. At the same time the
bar D is levelled by means of the pins c' which follow the curve c of the arm C*.
In order that the proprietor of the safe may change the key number at will, the
pointer is attached to a disc K carrying a pin which enters one of a number of holes
formed in another disc K¹ which is fixed to the sleeve F¹, so that the number for any
dial may be altered by slackening the nut k, on the spindle k¹ sufficiently to allow the
index plate to be drawn out for a distance equal to the length of the pin when the
index can be turned partially round and the pin inserted into a different hole. As it
may be desired at times to open the safe in the dark, I use dials having a raised
escutcheon L, the divisions of which are easily recognizable to the touch.
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. In an apparatus such as described, the combination with frame C¹ provided with
pieces T and arm C, of a rocking bar D, the rocking action of which is dependent on
the proper adjustment of the discs F, substantially as described.
2. In an apparatus such as described, the combination of arm C, levers G¹, rocking
bar H and check springs h, to engage with the teeth of the wheels J in manner and
for the purpose substantially as herein shown and described.
3. The combination of toothed wheel J, disc F, finger G, with perforated plate K¹,
upon which plate the index disc K may be adjusted, substantially as herein shewn and
described.
4. The raised escutcheon L for enabling the index fingers to be adjusted in the
dark, substantially as herein shewn and described.
5. The general improvements in locks for safes, such as I have herein described and
illustrated in the accompanying drawings.
Dated this 11th day of September 1889
HUGHES, ELI & HUGHES,
76, Chancery Lane, London, W.C., Agents for the Applicant.