Improvements in Electric Clocks.
Year: 1891

page_text: Date of Application, 25th June, 1891-Accepted, 12th Dec., 1891
Improvements in Electric Clocks.
I GERRIT LOLKES JANSMA VAN DER PLOEG Dr. Ph. & Jur. of Willemspark
(Koninginne Weg 18), Nieuwer-Amstel in the Kingdom of Holland 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 an electric clock or regulator for astronomical and other
purposes.
The apparatus consists mainly of a compensated pendulum swinging in an air
tight case and a clock-work connected with the former by means of electric
conductors.
These parts will each be hereinafter particularly referred to; they are all
essential as to the functions which they respectively fulfil, but their position,
dimensions, form and arrangement may be variously modified without departing
from the principles of the invention.
In order to make my invention more clear I refer to the accompanying
drawings in which similar letters, denote similar parts throughout the several
views.
Fig. 1 is an elevation of the upper part of the pendulum showing the contact
device.
Fig. 1 is a perspective view showing the arrangement of the circuits.
Fig. 2 shows the time indicating device and mechanism for operating the same.
Fig. 2 is a side elevation of the mechanism for operating the clock-work.
The compensated pendulum P (Fig. 1) is enclosed in an airtight casing into
which two wires of a battery pass, whilst two other wires pass from the case to the
receiver (Fig. 2 and 24). The holes in the case through which the wires pass should
be plugged up air tight, so that the pendulum P may be entirely free from the
atmospheric influence.
Four stationary metallic contact pieces having their ends curved, a¹ b¹ and c¹ d¹ are
arranged, two on the left and two on the right hand side of the pendulum (Fig. 14)
and four metallic springs a bed rest respectively on these points remaining in
contact with the same. The pendulum P when in a position of rest hangs between
the four spring contacts without touching them. When the pendulum P is set in
motion from right to left, the springs ac will be lifted from their points of
contact a' c; and on the return of the pendulum from left to right, the contact will
be re-established owing to the clasticity of the contacts a and c. While the springs b
and d on the right are removed from their respective points and d'.
The current from the battery e entering the pendulum apparatus passes to
the contact piece c on the one hand and on the other hand to the double
contact a¹.
This double contact a¹ b¹ enables the current to pass firstly by way of the spring b
to the pendulum operating electro magnet j and secondly by means of the spring a
to the electro magnet k in the clockwork all currents uniting on their return to
the battery.
The springs are advantageously formed of draw silver wire and fastened in
position by means of screws or clamp screws at a bed. Each of them so
as to rest on the corresponding metallic points a b c d with which it forms
contact. The pendulum in swinging from right to left, raises both the springs a and c
from their contacts, and on returning from left to right allows the same to
re-establish their contacts whilst it breaks contact at 6 and d. In the first case the
current passes through the electro magnet j in the pendulum apparatus whilst in

page_text: the second case it passes through the electro magnet k in the clockwork but at the
moment when the pendulum passes its nadir the current will not enter either of the
said electros being short circuited at c.d. As the current of the battery is never
broken, there will be no sparks at the contacts.
When the current reaches the electro magnet j of the pendulum apparatus, the
armature (Fig. 1) on lever g, which oscillates at h will be attracted and closes on
the magnet. The small spring i at the lower extremity of lever (Fig. 1) being
displaced and actuated against the pendulum P on which it exercises a slight
pressure sufficiently strong to keep up the motion of the pendulum. When the
pendulum swings back from left to right, the spring i is returned to its
former position; the current passing on through to the electro magnet k of the
clockwork.
Referring to Figs. 2 and 24 the current of the battery e now coming in the
vertical electro magnet k (Fig. 2,) causes its armature / to be attracted. This
armature being fixed to the lever m which oscillates at n is therefore alternately
depressed by the electro magnet and raised by the spiral o. A second lever is
arranged above the first lever to which it is coupled by the bar 9. This upper
bar P is pivoted at and oscillated in the opposite direction to the lever m. Both
levers are provided at their ends with uprights s and having hooks adapted to grip
in the pins of the double crown wheel n. The alternating motion of the ratchets
or pawls causes the crown wheel to revolve. If the pendulum is to strike
seconds, the crown wheel must have thirty teeth when it represents the seconds
wheel of the clockwork.
By adding the ordinary gearing minutes and hours may also be shown by hands
on a dial.
Having now particularly described and ascertained the nature of. my said
invention and the manner in which the same is to be performed I declare that
what I claim is:
1. In an electrically controlled clock or regulator having an intermittently
circulating current in which two pairs of normally closed contacts a and c d¹
are so arranged within the stroke of the pendulum that the latter two contacts c¹ d¹
opposite each other short circuit the current during the intermediate part of the
stroke of the pendulum and that by the other pair of contacts a¹ the current is
branched off on the one hand to the pendulum actuating electroj and on the other
to the electro & of the ratchet work or time indicating device so that on these
contacts being broken by the pendulum at the ends of its stroke the current will be
sent into one of the said branches substantially as described.
2. An electrical clock or astronomical regulator working entirely by the force of
magnetism constituted by the arrangement in combination of a compensated electric
pendulum working in an airtight case, and an electric clockwork, connected to
the former by electric conductors only; each such parts having the functions
respectively above specified, and being substantially of the construction or formation
above described, and as illustrated on the accompanying drawings.
Dated this 25th day of June 1891.
TONGUE & BIRKBECK,
34, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Patentee.