IMPROVEMENTS IN ALARM CLOCKS
Year: 1882

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"IMPROVEMENTS IN ALARM CLOCKS." A communication from abroad by
Jerome & Co. (Incorporated), of New Haven, Connecticut, United States of
America.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 24th May 1882.
WILLIAM ROBERT LAKE of the Firm of Haseltine Lake & Co. Patent Agents,
Southampton Buildings London. "IMPROVEMENTS IN ALARM CLOCKS."
A com-
munication from abroad by Jerome & Co. (Incorporated) of New Haven,
Connecticut, United States of America.
This invention relates to improvements in that class of clocks which combine
with the time movement an alarm attachment, and in which the alarm is operated
by the same spring which operates the time movement, that is to say, the main
wheel of the time part and the main wheel of the alarm part are arranged upon the
same shaft with the spring between them, the arrangement being such that the
spring will drive each wheel independent of the other.
In the usual construction when the escape is made to permit the alarm to be
sounded, the main wheel of the alarm revolves, but is arrested at the termination
of the first revolution, so that the time during which the alarm will be sounded is
limited to that single revolution of the main wheel.
The object of this invention is to permit two or more revolutions of the main
wheel of the alarm, whereby the time of sounding the alarm will be proportionately
prolonged, and it consists essentially in the arrangement of a finger upon the main
shaft, which will engage a toothed wheel, and impart to the said toothed wheel a
movement of one tooth at each révolution of the shaft, the said toothed wheel
having an extension, or elongated tooth at one point, which will engage with the
said finger, hold it and prevent its further rotation at the time when it shall have
performed at least two revolutions, and yet permit the re-winding of the spring at

page_text: the alarm only or for the full extent of winding; the
said invention consists also in details of construction, hereinafter described.
The said invention is illustrated in the accompanying drawing in which
Figure 1 is a front view of the clock.
Figure 2 is a rear view of the dial, showing the mechanism thereto attached.
Figure 3 is a front view with the dial removed.
,
Figures 3ª, 3b, 3c, and 3d, are views shewing parts of the mechanism detached.
Figure 4 is a rear view.
Figure 5 is a rear view shewing part of the bell and rear plate cut away.
Figure 6 is a vertical sectional side view drawn to an enlarged scale.
Figure 7 shews portions of the mechanism detached.
The movement here shewn is that designed for cylindrical or equivalent shaped
cases, and is of the "marine" class, but the said improvements are applicable to
movements of other shape, and to such as employ a pendulum.
A represents the front plate, and B the rear plate of the movement; the two
plates are secured together by pillars C, in the usual manner.
D is the main shaft on which the main time driving wheel E is placed loosely, so
as to permit the said wheel to revolve independently of the shaft, or the shaft
independently of the wheel. F is the main alarm wheel, arranged on the same
shaft D and also loose thereon. Between these two wheels the usual spring. G is
arranged, one end thereof being attached to the shaft D, as at a, the other to the
time wheel in the usual manner. Outside the alarm wheel Fand fast on the shaft,
is a toothed ratchet b, and on the wheel F is a spring pawl d, which engages with
the teeth of the ratchet in the usual manner for holding the main spring of the
clock so that a key H applied to the shaft D to rotate it, will wind the spring, the
pawl d engaging with the ratchet b to hold the spring as it is wound; when so
wound, one end acts directly upon the wheel F, in the usual manner for clock-
movements, and through its other end, attached to the shaft, its power is applied
to turn the wheel F.
The train of gearing connected with the main time wheel E, is of common
construction and arrangement, and needs no further description here except to say
that it imparts movement to the centre shaft I in the usual manner.
With the arrangement of the wheels E and F, and the attachment of the main-
spring above described, the time movement would continue until the point where
the alarm apparatus escapes, then the wheel F would be revolved by the spring,
and continue its revolution until the said spring was exhausted; the result of this
action would be, that the time movement would stop with the alarm; this was the
case with the original construction where the single spring was employed to operate
both the time and alarm. To obviate the running down of the spring a stop has
been arranged to arrest the alarm main wheel after it has performed a single
revolution, as hereinbefore mentioned.
To permit several revolutions of the wheel a finger e is attached to the shaft D,
which is arranged to revolve with the shaft, and preferably outside of the front
plate, as seen in Figure 3. Adjacent to this fingre e is a toothed wheel f; at one
point in its periphery is a projection h with which the finger e will engage, and
when the said finger is so engaged the revolution of the shaft D in the direction
of unwinding is impossible; but in winding the shaft, the finger e passes around
in the direction indicated by the arrow, and striking the projection h turns it up
one point, as seen in figure 3a, and continuing the rotation of the shaft, the next
tooth is engaged as in figure 3b, the spring dog i engaging the teeth of the wheel f
as it is so turned, thus holding it in the position to which the finger shall turn it
until the projection h comes nearly against the dog i as seen in figure 3º, then the
further turning of the wheel f will be prevented, but the spring dog i standing
against the projection h, will yield as the finger strikes the tooth presented on the
next revolution of the shaft and permit it to pass, as seen in figure 3d the reaction
of the spring dog bringing the wheel back to the position seen in Figure 3c, so
soon as the finger shall have escaped from the wheel; thus the turning of the shaft

page_text: will continue until the spring is completely wound, and when so wound, the spring
acts upon the time part in the usual manner, but when the alarm escapes from the
device which holds it until the required time, the wheelf will be permitted to
revolve by the action of the main-spring, and each revolution of that wheel brings
the finger into contact with one tooth of the wheel f, and turns it to the extent of
one tooth, and so continues, each revolution turning the wheel fone tooth, until
finally it is brought up against the projection has seen in figure 3, to arrest the
further movement of the alarm part; this operation will leave the remainder of the
spring to continue the time part.
The number of revolutions which the alarm wheel F will make depends upon
the number of teeth in the wheel f one tooth and one projection giving two
revolutions, two teeth and one projection three revolutions, and so on; therefore
by the use of this movable or rotating stop f I am enabled to give to the alarm
wheel two or more revolutions, thus prolonging to that extent the time during
which the alarm will sound.
Another advantage of this arrangement is that where a single revolution is
given to the wheel, and that revolution is arrested by a stop which is tripped to
permit the wheel to start when the alarm mechanism escapes, the alarm will be
sounded each twelve hours; whereas, when in this arrangement the alarm has run
down, that is to say, when the wheelf has performed its revolution, it cannot
operate again until the shaft be turned to rewind the spring to the extent of
its unwinding by the operation upon the alarm in the usual manner; hence if the
clock be a one day clock, or more, the alarm will sound but once, unless the spring
be rewound.
The mechanism between the main alarm wheel and the hammer is of common
construction; L represents the bell and P the verge to which the hammer is attached,
and through which the vibration is given to the hammer.
The tripping mechanism whereby the alarm is let off at the predetermined time,
consists of a spring lever see figures 6 and 7; this lever is attached to one side
of the front plate, and extends across to the opposite side where it turns backward
so as to engage an arm n on the alarm verge shaft, and when pressed backward it
holds the verge in contact with the escapement wheel, so as to prevent the
revolution of that wheel, but at the proper time the lever is permitted to spring
forward, as seen in broken lines, figure 7, which releases the verge, and permits the
revolution of the wheels and the vibration of the hammer.
This lever lies at the rear of the hour hand wheel m this wheel being loose upon
its shaft, so as to be easily thrown outward by the spring on the lever as indicated
in broken lines figure 7. On the hub of this wheel is stud projecting forward
against a cam 8 on a wheel t which is placed over the hollow shaft of the hour
wheel m as seen in figures 2 and 6. This cam 8 has a fall off, or escape u at one.
point, so that when the pin r arrives at that fall off, it escapes and permits the
levers to spring outward. The cam is set so that this fall off or shoulder u will
occupy such a position that the pin r will escape there-from at the time when
it is desired the alarm shall be sounded.
To adjust the cam to different times, it is attached to or made a part of the
wheel t arranged on the dial plate, as seen in figures 2 and 6, so as to revolve
freely upon, or concentric with, the hour wheel, this wheel t preferably has ratchet
teeth, and a spring w is arranged to operate upon the said wheel to prevent its
accidental or backward movement.
On the back of the dial is a vertical rod R, arranged in a guide T, so as to be
freely movable up and down therein, it is provided with a spring T¹, the tendency
of which is to throw the rod upward; this rod is provided at its upper end with
any suitable knob or handle by which it may be conveniently depressed; from
the lower end of the rod a finger T extends down so as to engage with the teeth
of the wheel; hence, by depressing the rod, as seen in broken lines, figure 2, the
wheel t will be turned, and with it the cam 8. To indicate the position of the cam
a pointer y is attached to the cam outside the dial, the shoulder being in such

page_text: relation to the said pointer and to the pin on the hour wheel that the pointer
will indicate the time on the dial when the pin r will escape from the shoulder
on the cam, that is to say, the pointer will indicate the time when the alarm will
be sounded.
Although I prefer to use the toothed wheelf and its projection h to engage with
the shaft so as to permit two or more revolutions before its arrest will take place,
other mechanism may be employed to thus permit the two or more revolutions
of the shaft and arrest its revolution after the said two or more revolutions are
completed.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same, I wish it understood
that I claim,
First. In a combined time and alarm clock movement, the combination of the
time main wheel and the alarm main wheel both loose upon the main shaft, the
main-spring with one end engaging the time wheel, and the other the shaft, a pawl
and ratchet between the said shaft and alarm main wheel which permits the
revolution of the shaft in one direction independently of the alarm wheel, a stop
and mechanism between it and the main shaft whereby the rotation of the main
shaft in winding the spring will turn said stop away from engagement with the
main shaft during the first two or more revolutions of the said shaft in winding
and then permit the continued rotation of the shaft to complete the winding, the
said stop operating to arrest the main shaft and the alarm main wheel in connection
therewith after two or more rotations in the opposite direction, all substantially as
and for the purposes set forth.
Second. In a combined time and alarm clock movement, the combination of the
time main wheel and the alarm main wheel, both loose upon the main shaft, the
main spring with one end engaging the time wheel and the other the shaft, a pawl
and ratchet between the said shaft and main alarm wheel, which permits the
revolution of the shaft in one direction independently of the alarm wheel, a finger
attached to the said main shaft, and revolving with it, the toothed wheel f
constructed with a projection h and the spring dog i, all substantially as and for
the purposes set forth.
Third. In a combined time and alarm clock movement, the combination of the
spring lever the hour wheel m provided with a stud r, and the wheel t provided
with a cam s substantially as, and for the purpose set forth.
Fourth. The combination of the toothed wheel t arranged concentric with the
hour wheel and carrying the pointer and the cam & with the sliding rod R
provided with a finger T2 to engage in the teeth of the wheel t and the mechanism
between the said cam s and the alarm mechanism all substantially as, and for the
purposes, set forth.
In witness whereof I the said William Robert Lake have hereunto set my
hand and seal this Twenty fourth day of May in the year of our Lord one
thousand eight hundred and eighty two.