Electrical Clockwork for Pendulum Timepieces.
Year: 1890

page_text: Date of Application, 28th Apr., 1890-Accepted, 2nd Aug.,
1890
COMPLETE SPECIFICATION.
Electrical Clockwork for Pendulum Timepieces.
I, EMIL SCHWEIZER of Basle, Switzerland, Clockmaker, 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 :-
My invention relates to an improved construction of electrical clockwork for
pendulum time pieces, which is of very simple construction and has a very quiet,
uniform movement.
It consists mainly of a vertical double electromagnet fixed on the platin of the
clockwork and which, when the electrical circuit is closed, attracts an armature to
which are attached firstly a pawi gearing with the minute wheel of the clockwork,
and a toothed sector acting upon the arbor of the escapement. wheel of an ordinary
pendulum escapement, so that when the circuit is broken, the weight of the armature,
pawl and sector effect the rotation of the minute wheel, as also the movement of
the escapement, while a special contact arrangement, actuated by the escapement,
effects the closing and breaking of the electrical circuit at the end of each
minute.
The construction and action of this electrical clockwork will be readily under-
stood on reference to the accompanying drawings in which Fig. 1 shews. a front
view, Fig. 2 a side view, shortly after the interruption of the circuit, Fig. 3 is a
vertical section on line X X Fig. 2, and shews a front view of the escapement;
Fig. 4, is a vertical section on line Y Y Fig. 1, and Fig. 5 a front view of the
mechanism at the closing of the circuit.
To the platin A is fixed the vertical double magnet B, by means of the pole
piece at its upper end. The armature of the electromagnet is attached to a
plate D pivotted at d. To the armature () is attached an arm E to which the
pawl F is hinge-jointed a spring always presses the pawl F against the teeth
of the minute wheel G, which is carried loose by the pin k on the bridge piece K,
so that on the interruption of the circuit, when the armature sinks by gravity, the
minute wheel G is turned one tooth by the pawl F. The motion of the minute
wheel is transmitted in the usual manner to the hour wheel J, through the
train H, I. A check-pawl j carried by the bridge K prevents the backward
motion of the wheel G when the armature C is attracted by the electromagnet so
that the pawl then takes into the next tooth space of G.
The armature C also carries a lever L which is formed at its upper end with a
toothed sector 1, the teeth of which gear with a pinion n loose on the arbor m of
the escapement wheel M, and consequently on the descent of the lever L, when
the circuit is broken, the sector effects the rotation of the pinion n, which carries
a disc O. On the arbor m is a loose ratchet wheel P having a pawl p which is
made by a sprip to take into a notch o in the disc O, so that the pinion n
on its rotation during the descent of the lever L, also carries the ratchet wheel P with
it, while on the closing of the circuit and consequent upward motion of L, the
backward motion of the ratchet wheel is prevented by a check-pawl p² carried by the
bridge K so that only the pinion n and disc U are then turned backward a complete
revolution, leaving P stationary.
As the edge of the notch o bears against the pawl p on the descent of the sector
during the breaking of the circuit the ratchet wheel will again be rotated on the
forward motion of the pinion n, until the circuit is again closed, and so on. A
pini Fig. 4 prevents the sector 1 from sinking beyond a certain point. The
ratchet wheel P transmits its rotation on the sinking of lever L to the arbor m
through a pin p³ Fig. 4 fixed thereto which presses against a curved spring m
on the arbor m, and the latter consequently imparts such motion to the escapement

page_text: wheel M fixed thereon, such motion being governed in the usual manner by the
pallets of the pendulum escapement Q. This escapement is so regulated that the
escapement wheel M and the ratchet wheel P make a complete revolution every
minute, and that the closing of the circuit is effected at the end of every minute, so
that the pawl F effects the turning of the wheel G one tooth every minute.
During the upward motion of the lever L, the rotation of the escapement wheel M
is effected by the tension previously put upon the spring m¹ by the pin p³, so that no
interruption of the motion of M takes place.
To the platin A are fixed in an insulated manner the two terminal screws r
of which is fixed on the insulating plate a and connects the one end of the wire coil
of the electromagnet with the one pole of the battery while the other screw ¹ is fixed
to a metal plate R fixed on the insulating plate a and connects the other pole of the
battery with the plate R.
The other end of the wire coil of the electromagnet is connected to an arm S
fixed in an insulated manner to the armature plate D. The slanting end of this arm
carries a screws and a contact pin s¹.
On the plate R is pivotted the double ended contact lever T. On the interruption
of the circuit as at Figs. 1, 2, & 3 the under surface of the triangular head u of the
spring U presses against the upper surface of the apex of lever T so that at the
commencement of the sinking of the lever I a projection of insulating material on
the outer end of the arm t is held lightly against the lower end of the screw S. Con-
sequently at the downward motion of the armature C the screw S presses the arm t
downwards until the apex t² of T passes to the upper side of the head u of spring U,
so that such upper surface in then pressing against the under surface of t³, forces the
lever T downwards, whereby the arm is brought in contact with the contact pin S',
as at Fig. 5, thereby effecting the closing of the circuit. The armature being now
attracted by the electro-magnet, the pin S' is made to move lever T upward again,
until the apex again passes under the apex of ", whereby the lever T will be moved
rapidly upward, causing the arm t¹ to move away from S¹ and thereby to break the
circuit again.
In order to prevent the oxidation of the metal at the points of contact, the
inner surface of the arm and the upper end of the pin S1 are coated with
platinum. A regulating screw v enables the position of the arm S to be accurately
adjusted.
From the above described construction it will be seen that the action of the clock-
work and electromagnet will be as follows.
As before stated, the escapement Q is actuated by a pendulum connected to its
arbor by the forked arm shewn in Figs. 2 and 3, as in ordinary clocks, so that the
pendulum allows the escapement wheel M and its arbor m to perform a complete
revolution in a minute.
Assuming now that the armature and lever L are in the lowered position shewn
at Fig. 5, then, as above described, the electric circuit is closed and the armature
being attracted by the electro-magnet, rises, and the toothed segment of L turns the
pinion and ratchet disc O loose on the spindle m..
As soon as the armature arrives in the raised position at Fig. 3 the circuit is broken
again, and the armature and arm L, in descending by gravity, cause a tension to be
put on the curved spring m² by the turning of the wheel P, whereby a tendency to
turn is imparted to arbor m and escapement wheel M as in the case of an ordinary
clock spring; at the same time the pawl F will cause the minute wheel to turn one
tooth. On the armature again arriving at the end of its downward motion, the
circuit is again closed, and the armature C and arm F rise up again as before,
the circuit being then again broken, so that the armature and arm tend to descend
again. But a tension having been put upon the spring m' by the previous down
stroke, the spring will only allow of the gradual descent of the arm L in exact
proportion to the rotation in the same direction of the arbor m and escapement
wheel M, as governed by the pendulum escapement, so that as the arbor m only

page_text: make one revolution in a minute it will also take one minute for the armature C
and arm F to complete their descent, and consequently the turning of the minute
wheel one tooth by the pawl F will also be effected in one minute.
From the above description it will be seen that the number of wheels of the clock-
work is reduced to four, that is to say, only an escapement wheel, and the train of
wheels for the minute and hour hands.
The construction of the contact device is also very simple and a perfect contact may
he relied upon.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-.
1. An electrical clockwork for pendulum time pieces wherein the armature C of an
electro magnet B is caused on its descent by gravity to rotate the minute wheel G
by means of a pawl F carried thereby such motion being governed by an ordinary
pendulum escapement, whose escapement wheel M is actuated through a spring m
attached at one end to its arbor m and having its other end acted upon by a pin p³
on a ratchet wheel P with pawl p taking into a notch o in a disc O fixed to the loose
pinion which receives motion from a toothed sector on a lever L carried by
the armature C, the controlled downward motion of the armature being made to
effect the closing of the electrical circuit of the electromagnet at the right moment.
2. In an electrical clockwork constructed as set forth in the preceding claim.
a. The contact device consisting of a bell crank lever T which has its position
reversed at the desired moment under the combined influence of a spring U
and arm S of the armature C, whereby it is put in and out of contact with a
contact pin S¹ so as to momentarily effect the closing and breaking of the
electrical circuit.
b. The device whereby the escapement wheel M is connected to the armature C
and which consists essentially of the lever L with toothe sector the pinion n
with disc O, pawl p gearing with notch o of disc O, ratchet wheel P with
pin p³, and spring mattached to arbor m of the escapement wheel, the
pinion n disc O and ratched wheel P being carried loose on the arbor of the
escapement wheel, so that on the rapid upward motion of the armature Con
its being attracted by the electromagnet, the lever L will only rotate pinion n
and disc O, while during the slow descent of the armature its movement is
transmitted by the parts Ln, o, p P p³, and m' to the escapement wheel M,
whose movements, controlled by the escapement Q, consequently regulate the
descent of the armature Cand the rotation of the minute wheel.
Dated this 28th day of April 1890..
ABEL & IMRAY,
Agents for the Applicant.