Improvements in Electrical Synchronizing Devices for Clocks.
Year: 1892

page_text: Date of Application, 13th July, 1892-Accepted, 29th Oct., 1892
COMPLETE SPECIFICATION.
Improvements in Electrical Synchronizing Devices for Clocks.
We, Doctor LUDWIG VON ORTH and EMIL BRESLAUER both of 11 Spandauer
Strasse, Berlin, in the Empire of Germany, 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 a device for electrically synchronizing by a standard
clock one or more other clocks. For this purpose it is necessary that the clock to
be regulated should go a little too fast, so that the regulation can always be effected
hy temporarily stopping it.
The accompanying drawings show the new regulating device.
A shaft a Figs. 1 and 2 of the clock to be regulated carries a disc 6 provided,
with a projecting nose c. There is arranged below the disc ba lever d having its
fulcrum at f; one end of the lever d carries the armature e of an electro-magnet E
while the other end carries a knife-edge or detent 9. To the shaft f of the lever d
is secured an arm h carrying a horizontal arm in such a manner, that, when the
armature e is attracted by the electro-magnet E, and the lever d thereby turns
upon its pivot f, the arm h¹ strikes against the disc b, while at the same time the
edge g of lever d is raised. The connection of the pendulum or of the pendulum
rod p with the pallet arbors is established by a crutch i, which does not, as is usual,
embrace by a fork, the pendulum rod, but enters with a bent rod k into an opening
arranged in the pendulum p, so that the bent rod k bears against a projection pl
secured to the pendulum rod. The bent rod k is jointed to the crutch i and provided
with a weighted plate / pressing the angle of the rod k underneath the projection p',
so that the connection of the pallet arbours with the pendulum rod p can easily be
broken. When the armature e is attracted by the electro-magnet E and thereby.
the lever d turned upon its pivot f the edge g rising is brought into engagement
with the serrated plate l so that the bent rod k provided with this plate turns,
round its fulcrum on crutch i downwards and the connection between lever i and
the pendulum then ceases. If at the moment that the edge g is raised the pendului
has not reached its extreme position to the right hand in the drawing Fig. 1.
pushes at the next oscillation the crutch i to the right hand, the ratchet teeth
passing over the edge or detent o. At the return stroke of the pendulum to the
left hand the plate remains engaged with the edge y and the nendulum continues
to oscillate without the crutch partaking of this oscillation.
This clock is regulated in the following manner,-
The standard clock closes, when for instance the regulation has to take place ar
12 o'clock noon, a short time say a minute before 12 o'clock, an electrical contact.
whereby the electro-magnet E of the clock to be regulated which is electrically
connected to the standard clock is excited. The armature e is attracted by the
electro-magnet and the lever d is turned, but a complete attraction cannot take
place as the arm h' strikes against the circumference of the disc b.
The point of the nose c of the disc is applied in such a manner that exactly at
12 o'clock i.e. according to the time of the clock to be regulated it is in front
of the arm h¹ so that the latter slides over the nose c and allows of a complete
attraction of the armature e of the electro-magnet E. But with this complete,
attraction of the armature e is combined the rotation of lever d and in consequence
thereof the connection of crutch i with the pendulum rod p ceases so that the
pendulum continues to swing while the movement of the clock train stops.
As already above mentioned it is necessary that the clock to be regulated goes a

page_text: little too fast. Assuming the clock to have gained half a minute since it was last
regulated then half a minute before the exact time indicated by the standard clock,
the armature e will be attracted by the electro-magnet E and the going train of
the clock to be regulated will be stopped while the pendulum continues to swing.
The standard clock is provided now with such a device that exactly at 12 o'clock
the current utilized for exciting the electro-magnet E is broken. Exactly at
12 o'clock therefore the armature e will be released and the crutch will be
connected again with the pendulum rod p so that the going train of the clock to be
regulated which was stopped, when its hand was at 12 o'clock will be put in motion
again as soon as the standard clock indicates 12 o'clock. The clock to be regulated
shows therefore the same time as the standard clock.
A second device acting in a similar manner, is shown in Figures 3 and 4.
The crutch connecting the pallet arbour with the pendulum rod P does not
embrace the latter like a fork but bears against the same only on one side. The
crutch i carries on this side a short arm m made of soft iron and oscillating with
the pendulum p. The iron rod enters and leaves as it oscillates, the cavity of a
spiral coil or magnet D. In order that the crutch i engaging the pendulum rod
only on one side shall, while the. clock is going, always bear on the pendulum rod,
a small weighted lever n is arranged on the shaft of the pallet arbour.
This regulating device acts in the following manner,
The standard clock closes the contact some time before 12 o'clock. The electric
current cannot flow through the magnet D until the clock to be regulated has closed
automatically by means of a suitable contact device the circuit and so allowed the
current to pass through the spiral coil D. The clock to be regulated is stopped
thereby at 12 o'clock according to the time indicated by it and this in such a manner,
that the iron core m fastened to the crutch i is retained on closing the circuit in the
spiral magnet D. The pendulum of the clock continues then to swing alone while
the going train of the clock is stopped. As soon as the standard clock shows
12 o'clock the current is broken by this clock whereupon the coil D releases the
iron core m and re-establishes the connection between the crutch i and the pendulum
rod pi.e. the going train of the clock to be regulated is put in motion again
exactly at 12 o'clock so that the standard clock and the clock to be regulated show
the same time.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, we declare that what I
claim is,―
1. A device for electrically synchronizing clocks characterized by a lever d
movable upon its pivot f and one arm of which carries an edge or detent g and the
other arm the armature e which owing to the closure of an electric circuit by the
standard clock is attracted by the electro-magnet E while the arm of the lever h
fastened to the same shaft as lever d slips over the nose c of the revolving disc b
and permits the lever d to turn the edge g of the latter engaging the teeth of the
plate whereby the bent rod k is turned" and the connection of the crutch i with
the pendulum rod p is broken and the clock stopped until at the exact time it is
put in motion again by the standard clock breaking the circuit whereupon the
armature e is released and the crutch i is re-engaged automatically with the
pendulum rod so that the clock starts again substantially as described and illustrated
in Figures 1 and 2 of the accompanying drawings.
2. A device serving the same purpose as that pointed out in Claim 1 which device
is characterized by the arrangement of an iron rod or core m on the crutch i
bearing on one side against the pendulum rod the said crutch being
retained when the electric circuit is closed from the standard clock by
the agency of the clock to be regulated by the spiral coil or magnet and
the clock being stopped thereby until from the standard clock the current
is broken again so that the core m and the crutch are released and

page_text: the train is put in motion again substantially as described and illustrated in
Figures 4 and 5 of the accompanying drawings.
Dated this 13th day of July 1892.
W. P. THOMPSON & BOULT,
Agents for the Applicants.