Improvements in Watches and Clocks,
Year: 1896

page_text: Date of Application, 30th Jan., 1896-Accepted, 9th Jan., 1897
Improvements in Watches and Clocks,
I, HUGO HEILMANN of Dessau in the Duchy of Anhalt in the Gerinan Empire,
Watchmaker, 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:-
This invention relates to watches and other timepieces and consists in improve-
ments in the arrangement of the hands or index motion and details thereof which
are applicable to watches, clocks and other timepieces, the objects of said improve-
ments being to obtain greater compactness and simplicity of construction.
The improved motion of the hands is shown by Figs. 1 and 2 applied to minute
and hour hands, and by Figs. 3 and 4 in combination with a seconds hand.
While hitherto for all kinds of watches or timepieces which have hour and
minute hands on the same axis, there are required quite a number of parts (as a
minute pinion, change wheel with pinion, a stud or cock for the latter; for modern
watches the square with arbor and disc, for keyless watches the wheels for the
hand motion) there is in the improved motion only a single cog and a simple
retaining spring in order to effect the required ratio of motion.
As will be seen from the figures, the minute band M is fixed on the centre
wheel spindle n while the hour hand S is fixed upon the sleeve s¹ of the hour
wheel U, which can revolve loosely on the centre wheel spindle n. A single cog t
driving the hourwheel is fixed on the arbor t of the third wheel b, and rotates with
the same.
If now the hour wheel U is made with 72 teeth, and the cog t¹ makes
6 revolutions for one revolution of the centre wheel spindle n or the minute hand M,
it will propel the hour wheel U by 6 teeth or revolution for one revolution of
the minute hand, which corresponds with the correct ratio of motion of the
minute wheel to that of the hour wheel. As seen from Fig. 1, the hour wheel
is retained in its position by a spring acting as a pawl or click.
If to the arrangement of hour and minute hands a further seconds hand is
to be added, this can be done in the manner shown by Figs. 3 and 4. In this
case the seconds pinion is arranged exactly above the perforated pinion a' of
the centre wheel, and the arbor of the former passes through the spindle n on
which the centre pinion and wheel are mounted and which carries the minute
hand M. The third wheel b is so calculated as to gear with the seconds
pinion and drive the arbor at the correct speed relatively to the minute
hand, the arbor carrying in front the seconds hand s.
With these arrangements of wheel the setting of the hour hand to the correct
time has to be done by turning the hand itself, which however is easy as there
is at most half a revolution required. For instance, for changing the hand from
12 to 6 o'clock, only the hour hand has to be turned from 12 to 6, while with
the usual watches the minute hand has to be turned round 6 times.
However, an arrangement can be made for setting the hour hand by means
of a key from the back. This may be done by arranging the spindle t and the
wheels thereon as shewn by Fig. 5. The spindlet of the wheel is forined with
a square protruding through the back plate p for a key, and the wheel b and
pinion a² are connected to the spindle t by friction. For this purpose the wheel b
is fixed on a long sleeve of the pinion a. The boss of the single cog wheel t¹
is prolonged and turned conical, and the pinion a² is bored out to fit the cone.

page_text: The cog wheel t¹ and cone are fixed upon the spindle t, while the pinion a² and
wheel bare loose upon it and pressed down upon the cone by a spring placed
between the wheel 6 and a collart on the spindlet. The friction on the cone takes
the spindle round with the pinion a' and the single cog wheel t operates the hour
wheel u while the watch is going, and allows of the spindle to be turned round
by the key to set the hour hand without interfering with the motion of the wheel-
work of the watch.
For clocks with striking arrangement the minute hand bush n is fitted with a
small disk carrying the necessary disengaging pegs.
Having now particularly described and ascertained the nature of my said inven-
tion and in what mauner the same is to be performed, I declare that what I
claim in watches and timepieces is :
1. The improved arrangement for driving an hour hand on the same centre as
the minute hand by means of a single cog on the spindle of the third wheel
actuating an hour wheel mounted with a sleeve on the centre wheel spindle, in the
correct ratio, said wheel being preferably held in position by a click spring,
substantially as hereiubefore described with reference to Figs. 1 and 2 of the
drawings.
2. In combination with the improved arrangement for driving the hour hand,
the arrangement of driving a centre seconds hand by means of a seconds pinion
fixed above the perforated centre wheel pinion upon a spindle passing freely
through the boss of the centre wheel and pinion and supported therein, sub-
stantially as hereinbefore described with reference to Figs. 3 and 4 of the
drawings.
R. J. URQUHART,
57, Barton Arcade, Manchester, and 5, Clayton Square, Liverpool,
Consulting Engineer and Patent Agent.