An Improved Alarm Clock.
Year: 1898

page_text: Date of Application, 15th Nov., 1898-Accepted, 7th Jan., 1899
An Improved Alarm Clock.
I, BENJAMIN JOSEPH BARNARD MILLS, of 23, Southampton Buildings, in the
County of London, Patent Agent, do hereby declare the nature of this invention
(a communication to me from Gebrüder Junghans, Clock, Manufacturers, of
Schramberg), and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
The object of this invention is a repeating alarum or aların apparatus, with
intermittently acting ringing mechanism, the basis of such bring an alarm clock
construction, in which the alarm mechanism is set in motion in the usual manner
by the disengaging of the alarm indicator shaft, whilst an independent disengaging
apparatus, which is in connection with the clock work, serves to make the running
down of the alarm mechanism intermittent. A feature of the new invention is
the arrangement of the arm intended for putting the alarm mechanism out of
engagement with the clockwork in such a manner that the said arm is adjustable
in relation to its position of rotation and can be drawn against the clockwork to
be put out of engagement into the locking and supporting position of the arm by
means of a suitable contrivance on the alarm mechanism.
In the accompanying drawings, the alarm apparatus is illustrated by means of
two views Figures 1 and 2, sufficiently to explain its essential parts.
Fig. 1
shows the locking position, whilst the alarm has the tendency to act, and in order
to be put into action, requires only the disengaging of the clock work wheel.
Fig. 2 shows the unlocking position, which also corresponds to the position of rest
of the alarm apparatus in a non-active condition.
In Figures 1 and 2, only the lower part of the bell hammer n
is shown, viz., that lying nearest to its operating escape-
ment or ancher m. The escapement or anchor m is caused to oscillate in
the usual manner from the alarm cylinder i by means of the wheel and star
wheel h. The first releasing of the ringing mechanism at a determined time is
effected by the usual means, no notice of which has been taken in the drawing,
a spring bolt being caused (or allowed to) move out of the range of a "butt
belonging to the hammer shaft, by means of a pin belonging to the alarm indi-
cator shaft. Independent of this disengaging is the ratchet wheel contrivance
whereby the ringing mechanism is caused to act intermittently, after it has been
once released by means of the apparatus just indicated.
The engaging and disengaging arm c constitutes the essential part of the new
arrangement and is not merely capable of oscillating on the fixed pivot p, but at
the same time adjustable thereon by means of the slot q. By means of a light
spring, which however does not impair the adjustablity thereof, the arm c is
usually held in the position shown in Fig. 2. The arm is furnished with a pro-
jection d, having in this case the form of a pin, and a spring extension b, which
is intended to act with the clock work mechanism disengaging apparatus which
is in the form of a wheel a. The temporary locking of the alarm mechanism
released for the purpose of action, the arme having been adjusted, is effected by
means of the projection and the action of the nose g belonging to the alarm
mechanism wheel k in the following manner.
As soon as the bell hammer is released and allowed to oscillate freely at the

page_text: determined time, according to the setting of the alarm indicator, the alarm
mechanism is set in motion, the parts being in the position represented at Fig. 2.
In consequence of the rotation of the wheel k in the direction of the arrow the
nose g comes into contact with the projection d of the arm and draws the same
to the left into the position shown in Fig. 1. As the further movement of the arm c
is impossible, as soon as the pin lies against the right end of the slot q, the
alarm mechanism is locked so as not to run down any further, provided that the
spring extension b of the arm crests on a tooth of the wheel a, by means of its
lower end, which is pressed against the clock work wheel a. The resting point so
presented slips back downwards in consequence of the slow rotation of the wheel a
which occurs in the direction of the arrow, until the nose g which is pressing
against the projection can slide away and in consequence, the alarm mechanism
is released for further action. The arm e is now at once drawn back into the
position shown in Fig. 2, by means of the spring w. In the course of the follow-
ing periods of activity of the alarm mechanism, the wheel k is rotated again until
the nose g strikes against the projection d and in consequence of the pushing of
the arm to the left and the resting of the spring b on the wheel a, the described
process of locking and subsequent releasing again of the alarm mechanism is
repeated until the last named has run down.
The arrangement can be so contrived that the locking is not effected every time
the nose g comes into contact with the projection d, but that the former may alter-
nately pass and stop the latter whereby the periods of activity of the alarm
mechanism are correspondingly prolonged, in other words, doubled. The alter-
nate activity mentioned can be effected as follows:-
Tooth divisions on the wheel a are suitably arranged, so that from time to time, 2
when the arm c is drawn against the wheel a by means of the nose g, the spring b
lies on a half tooth division and consequently is not supported in the manner (or
to the extent) necessary for the effectual locking position of the arm c.
When the alarm mechanism acting intermittently in the described manner,
has run down, the nose 9 no longer exercises any pressure on the projection d and 3
the arm e falls back into the position shown in Fig. 2.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
An alarm clock with intermittently acting ringing mechanism, characterized by 3
an adjustably arranged engaging and disengaging arm c, which in consequence of
its projection d being pressed against by the nose belonging to the alarm
mechanism wheel, is pushed from time to time against the clock work wheel a
serving to support the spring extension b of the engaging and disengaging arm c
as well as for putting the last named out of engagement substantially as herein 4
set forth.
Dated this 15th day of November 1808