IMPROVEMENTS IN ELECTRIC CLOCKS
Year: 1885

page_text: We AUGUSTUS WILLIAM RIXON, Solicitor, and RICHARD THEILER, Telegraph
Engineer of 10, Austinfriars in the city of London do hereby declare the nature
of our Invention for IMPROVEMENTS IN ELECTRIC CLOCKS 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 of very simple construction and
reliable action.
In order that it may be more readily understood, we have illustrated our
invention in the accompanying drawing and will describe it with reference thereto
and to the letters marked thereon.
GG, represents the dial plate and H H the frame and train of any ordinary
clock-movement, in which, however, there is no spring-barrel or weight pulley.
E E, is an electro magnet connected with a battery in such a manner that when
the contact-maker A touches the insulated stop P, an electric current traverses the
coils E E, and the armature M, pivotted at B is forcibly and instantly attracted
towards the poles e e¹.
As soon as the armature M touches the said poles e e¹ the current is interrupted
and the spiral spring N retracts the armature towards the stop P, but cannot do so
without driving the clock.
We will now proceed to describe the manner in which this is accomplished.
The motion of the armature M between the stop P and the poles of E E¹, is
communicated to the ratchet-wheel Z by means of the link f which connects the
extremity of M with the crank or arm p. The driving wheel W which is loose
upon its axle, carries a click and spring as shown in drawing and is therefore
connected with the wheel Z and the arm p in such a way that it revolves with Z
only when the armature M is moving away from e e¹.
We generally provide the ratchet wheel Z with 60 teeth and make the driving-
wheel W of the same diameter as the centre- or hour-wheel t of the clock
movement.
By adjusting the motion or play of the armature M so that it is equal to 1/60 th of
a complete rotation of the wheel Z, the spring N will therefore drive the clock for
one minute.
This arrangement we find most suitable when the battery consists of 2 Leclanché
cells.

page_text: With more battery-power we make the wheel W larger than t; with less
battery-power smaller than t.
If electric contact was made by the direct action of the armature M, the result
would be a rapid vibratory motion of M which would be incapable of driving the
clock and would soon exhaust the battery.
In order to obviate this and obtain the full motion assigned to M, and necessary
for driving the clock, we employ the following device.
Electric contact is made by the arm A, which turns on the stud K with a certain
amount of friction and therefore remains stationary in whatever position it is
placed, until removed. The extremity of this arm A, opposite the adjustable
contact stop P is faced with platinum; the other extremity is fork shaped, the
opening of the fork being adjustable by means of a clamp screw as shown. The
pin S, on which the link f turns, is made to project from M and enter the forked
end of A as shown.
It will be seen that by this device, the arm A only moves when the pin S, fixed
to the armature M, pushes against either of the prongs of A, but remains
stationary while the said pin travels between the prongs of A.
When therefore the pin S pushes the arm A against P, contact will remain
uninterrupted until the armature has performed the movement assigned to it and
is almost touching at e e¹ as shown in the drawing. At that moment A is pushed
away from P, the current is interrupted and remains so while the spring N retracts
the armature and thereby drives the clock for the space of one minute, when the
pin S arrives at the opposite prong of the fork and pushes A with the whole force
of N against P again.
Contact being thus made with absolute certainty and not oftener than once in a
minute, the clock hereindescribed will continue to go for many months without any
attention.
We sometimes arrange the arm A to make contact with another circuit besides
that which actuates the electro magnet E E' and thereby drive any desired number
of secondary clocks indicating uniform time with the primary clock hereindescribed.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is
First. The Electric Clock constructed, arranged and operating substantially as
hereindescribed and shown in the accompanying drawing.
Second. An electric Clock driven by the retracting spring of the armature of an
electro-magnet.
Third. In an electric clock, the combination of a pivotted armature with the
crank of a ratchet wheel substantially as shown and described.
Fourth. In an electric clock, the device for periodically making and breaking
the electric circuit in a manner substantially the same as shown and described.
Dated this 30th day of January 1885.