Improvements relating to Watches and Clocks.
Year: 1890

page_text: Date of Application, 19th Nov., 1890
Complete Specification Left, 19th Aug., 1891-Accepted, 19th Sept.,
1891
PROVISIONAL SPE
ION.
Improvements relating to Watches and Clocks.
I, OSWALD IVAN MILNE, of Ellerslie, Beverley Road, Barnes Common, in the
County of Surrey, Secretary to Public Company, do hereby declare the nature of
this invention to be as follows:-
This invention relates to watches and clocks adapted to the 24 hours system,
the object of the invention being to simplify the construction of the same.
When employing the 24 hours system, it has hitherto been generally found
necessary to construct the watch or clock especially for that system.
Now, according to my invention, I may make use of any ordinary watch or
clock, and I may adapt thereto, in front of the ordinary dial, a second dial having
openings to show the figures on the ordinary dial.
The figures on this dial I may arrange in two circles, the numbers 1 to 12 in
the outer circle, and the numbers 13 to 24 in the inner circle. The openings in
the second dial I also make in two circles, but those in the inner circle would
be intermediate of those in the outer circle.
This dial may be provided with a means whereby it may be shifted once in
every twelve hours to expose the proper circle of figures, such as a spring which
is gradually wound up and suddenly released, in a manner well known in the trade.
In some cases I may make the figure dial move, and instead of two rows of
figures, I may have one row, the second dozen figures being arranged alternately
of the first dozen.
In this form, the figure dial may be provided with two springs, arranged to
act in opposite directions, so that the dial will be caused to move in opposite
directions once in every twelve hours, to bring the proper numbers opposite the
openings in the second dial.
Other means may also be employed for moving either dial as and at the periods
required, without departing from the nature of my invention.
Deted this 19th day of November 1890.
NEWTON & SON,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to Watches and Clocks.
1 OSWALD IVAN MILNE of Ellerslie, Beverley Road, Barnes Common, in the
County of Surrey, Secretary to Public Company, 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:—
The object of this invention is to simplify the construction of watches and clocks
to be used on the 24 hour system.
In carrying out my invention, I form openings in the dial where the figures
would ordinarily be placed, and I employ a second dial situated behind the main
dial, and provided with the figures.
I prefer to use black and red figures, the black representing 1 to 12, and the
red, which are alternate with the black, 13 to 24.
The figure dial is mounted on a central shaft, and is arranged to move in
opposite directions every twelve hours by means of mechanism, which will be
hereafter described, actuated by the main spring or other actuating device.

page_text: In the accompanying drawing,
Fig. 1 shows the front of a clock constructed according to my invention; and
Fig. 2 is a back view, with the clock mechanism removed, and showing the
means for operating the oscillating dial.
Fig. 3 is a vertical section, and
Figs. 4 and 5 show details of the operating mechanism in two positions.
A is the main dial, in which the openings A¹ are formed. B is the second, or
oscillating, and figure dial, which is mounted on the central arbor B. Slotted
openings are made in this dial, to allow of the clock mechanism frame being
attached to the main dial.
a represents a toothed wheel which operates the hour hand, and is mounted on the
centre arbor, and driven in the usual way. On the same arbor is the canon pinion b,
which gears with a second pinion c, of the same diameter, mounted on a short arbor
in the usual way, and provided at back with a snail cam d. On a suitably placed
pivot is mounted a bell crank lever e, one arm of which, under the influence of a
spring, presses, by a pin, against the snail cam d, and the other arm is provided
with a trip pawl which takes into the teeth of a ratchet wheel mounted on a stud
carried by the main dial. At the back of the ratchet is a second snail cam g, see
Figs. 4 and 5, the ratchet wheel being removed. are two levers or arms
suitably pivotted to the main dial A, and provided with pins or projections /³,
which are caused to bear against the snail cam g by the springs h³. On the back
of the figure dial are two pins or projections i, against which the arms h h bear.
Pivotted to the main dial A, so as to hang between the arms ', is a swinging
piece j, provided with two curved arms j³, carrying catches or pins which take into
notches formed in the edge of a slot in the figure dial B. The curved arms j¹
are pressed down, so that the catches enter into the notches, by springs 1 carried
by the dial B.
The operation of the parts is as follows:-The snail cam d is rotated once in
every hour, and the cam rocks the lever e, and causes the trip pawl to pass one or
more (as the case may be) teeth of the ratchet f. When the cam hins made a
complete rotation, and the pin of the lever e passes the cam surface, the lever e is
forced back by its spring, and the pawl catching the teeth of the ratchet wheel f,
moves this wheel the distance of one tooth. There are 24 teeth, on the ratchet
wheel, and it is rotated therefore once in 24 hours. In like manner, the cam g, on
the back of the ratchet f, will be rotated once in 24 hours.
Referring now to Fig. 4, the dial B has just been moved in the direction of the
arrow by the arm / (its pin / having passed off the cam surface) pressing against
the pin i, under the influence of the spring h.
As the cam rotates, the arm / will be pushed outwards away from the pin i, and
the arm will be held until its pin 2 passes off the cam surface, when, under the
influence of its spring h³, the arm h¹ will be pressed inwards, and acting against the
pin, will push the dial B in the opposite direction, bringing a new set of figures
before the openings in the dial A.
At the same time, as the arm h¹ moves, it will rock the piece j, and the catch at
the end of the curved arm j¹ will enter its notch k in the dial B, thus locking the
dial in its new position, as shown at Fig. 5.
As the cam continues to rotate, the other arm h¹ will be pushed outwards, and at
the proper moment the arm h, operating on the pin i, will push the dial B back
again into the position shown at Fig. 4, bringing the other set of figures before the
openings in dial A, the dial B being thus moved in opposite directions every
12 hours.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The improvements in watches and clocks as herein shown and described.

page_text: 2. The combination, in a watch or clock, of a perforated fixed dial, an oscillating
figure dial, and a mechanism, substantially as herein shown and described, for
operating the said figure dial.
Dated this 18th day of August 1891.
NEWTON & SON,
Agents for the Applicant.