IM- PROVEMENTS IN APPARATUS POR SOUNDING ALARM OR SIGNAL BELLS
Year: 1864

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of "IM-
PROVEMENTS IN APPARATUS POR SOUNDING ALARM OR SIGNAL BELLS."-A
communication from abroad by Paul Baudet, of Paris, in the Empire
of France.
Sealed the 31st January 1865, and dated the 1st September 1864.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 1st September 1864.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN APPARATUS FOR SOUNDING ALARM OR SIGNAL BELLS," a
communication to me from abroad by Paul Baudet, of Paris, in the Empire
of France, to be as follows:-
This Invention relates to a peculiar construction, arrangement, and combina-
tion of apparatus or mechanism for sounding alarm, signal, or call bells at any
required intervals of time in one or more parts of a building or works, and
consists of a clock movement or train of wheels and pinions actuated by an
ordinary barrel spring or by a weight, such clock movement being started or
set in motion at such times as the signals are to be given by the action of a
clock or timepiece with which it is in connection. The clock movement or
train of wheels abovo referred to consists of a large toothed wheel gearing

page_text: into a small pinion, on the axis of which pinion there is fitted a second large
wheel gearing into a second small pinion. The axle of this last-mentioned
pinion carries at one end a notched disc, into which is engaged a projecting
tooth on a vertical detent lever which works on a centre at its lower extremity,
the tooth serving as a detent to stop the movement of the train of wheels until
it is withdrawn from the notch in the disc above referred to by the action of
special mechanism in the clock or timepiece as herein-after described. An
inclined projection is formed on the detent lever below the detent or tooth, and
engages into one or other of a series of inclined notches in a disc on the axle
of the first of the large toothed wheels herein-before referred to, such axle also
carrying an ordinary barrel spring or a drum for receiving the cord of the
weight as the case may be. On the opposite end of the axle of the pinion
which carries the notched detent disc herein-before referred to there is fitted a
second disc having a pin or stud in the face thereof, which engages in a vertical
slot made in the upper end of a hammer shank, the lower end of such shank
carrying the hammer head which strikes the alarm; signal, or call bell. This
bell may be of any size or form according to the distance at which the sound is
intended to be heard. So soon as the detent is withdrawn from its notched
disc the spring or weight, as the case may be, causes the train of wheels and
pinions to revolve, and as the disc which carries the pin or stud rotates at a
high velocity it causes the hammer to vibrate rapidly and strike the bell twice
for every revolution. The ordinary flyer or regulating vanes are employed for
regulating the speed of revolution of the hammer actuating disc. The ringing
of the bell continues until the inclined projection on the vertical detent lever
drops into the succeeding one of the series of inclined notches in the disc
before referred to, whereupon a helical or other spring, by acting on the lever,
causes it to bring the detent against the notch of the first-mentioned or detent
disc, thus stopping the inotion of the wheelwork and consequently, arresting
the ringing of the bell till further required. The disengagement of the detent
lever by the clock or timepiece is effected by the following arrangement of
mechanism The upper end of the detent lever is prolonged upwards, so as to
bear against the lower end of a disengaging lever, which lever is made flexible
in the direction of its thickness, and works on a centre situate some little dis-
tance from its lower extremity. The upper end of the 'disengaging lever-formis
a circle or ring, which surrounds the minute wheel of the clock, but is not
quite in the same plane therewith. The minute wheel carries a tappet-wheel
provided with one or more tappets according to the number of times. in the
hour which it is required to' sound the bell, for example, if. it be required to
sound the bell at minimum intervals of one quarter of an hour, then four

page_text: tappets or teeth will be required on the tappet wheel. The teeth of this tap-
pet wheel are intended to operate upon the end of the disengaging lever, but
as this lever is situate out of the plane of revolution of the tappets, they will
only act upon it when the latter is brought into the same plane. A circle of, say,
48 holes, namely 4 holes for each hour, is formed in the dial or clock face, and
a stationary pin is inserted into one or other of these holes, which corresponds
to the time at which the signal or alarm bell is to be sounded. The hour
wheel of the clock carries on its face a curved spring, which is fixed at one end,
and carries at the opposite end a small pin which enters a hole in the wheel,
and remains flush with the opposite face of the wheel so long as the spring
which inclines outwards towards the end at which the pin is situate is not
pressed upon. Supposing it be required to sound the bell at the hour of 4,
the stationary pin is inserted into the hole corresponding to that hour, and
projects slightly through the dial. As the hour wheel revolves it brings the
curved spring against the stationary pin, and as this spring forms an incline
plane, it will on passing the stationary pin be forced inwards or against the
hour wheel, and cause the pin on its free end to protrude beyond the face of
the wheel. This pin presses against the circle on the end of the flexible dis-
engaging lever, and deflects slightly the end of that lever so as to bring it into
the plane of revolution of the tappet wheel. One of the teeth of this wheel
will then push the disengaging lever to one side, and by so doing will cause
the detent-lever to be released from the-notch in-the detent-disc herein-before
referred to, the result being the immediate ringing of the bell. The same.
effect is obtained each time the curved incline spring passes a pin in the dial,
any number of which may be employed, according to the number of times the
bell is to be sounded during the 12 hours. It is proposed in some cases to
establish an electrical communication between two or more of these apparatus,
so that they shall all work in concert, as is well understood by electricians.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 1st March 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of September, in the year of our Lord-

page_text: One thousand eight hundred and sixty-four, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Henry Johnson, Her special licence that I, the said
John Henry Johnson, my executors, administrators, and assigns, or
such others as I, the said John Henry Johnson, my executors, adminis-
trators, and assigns,, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein ex-
pressed, should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN APPARATUS FOR SOUNDING
ALARM OR SIGNAL BELLS," a communication to me from abroad by Paul Baudet,
of Paris, in the Empire of France, upon the condition (amongst others)
that I, the said John Henry Johnson, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said "Invention,
and in what manner-the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the accompanying Drawings,
and to the letters and figures marked thereon, that is to say:-
The said Invention relates to a peculiar construction, arrangement, and com-
bination of apparatus or mechanism for sounding alarm, signal, or call bells at
any required intervals of time in one or more parts of a building or works, and
consists of a clock movement or train of wheels and pinions actuated by an
ordinary barrel spring or by a weight, such clock movement being started or
set in motion at such times as the signals are to be given by the action of a
clock or timepiece with which it is in connection.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose shall
refer to the several Figures on the annexed Sheet of Drawings, the same
letters of reference indicating corresponding parts in all the Figures.
Fig. 1 of the Drawings represents a front view of the apparatus complete,
drawn full size; Fig. 2 is a corresponding side or edge view of the same, and
Figs. 3 and 4 are details which will be herein-after more fully referred to.
The clock movement or train of wheels above referred to consists of a large
toothed wheel A gearing into a small pinion B, on the axis of which pinion

page_text: there is fitted a second large wheel C gearing into a second small pinion D.
The axle of this last-mentioned pinion D carries at one end a notched detent
disc E, into which is engaged a projecting tooth F on a vertical detent lever G,
which works on a centre II at its lower extremity, the tooth serving as a de-
tent to stop the movement of the train of wheels and pinions A, B, C, and D,
until it is withdrawn from the notch in the disc E by the action of special
mechanism in the clock or timepiece connected with the apparatus, as herein-
after described. An inclined projection I is also formed on the detent lever G,
and engages into one or other of a series of inclined notches a in a disc K on
the axle of the first of the large toothed wheels A, such axle also carrying an
ordinary barrel spring or a drum L for receiving the cord of a weight M, as the
case may be. On the opposite end of the axle of the pinion D to that on which
is fixed the notched detent disc E there is fitted a second disc N, having a pin
or stud O in the face thereof, which engages in a vertical slot P made in the upper
end of a hammer shank Q, the lower end of such shank carrying the hammer
bead R, which strikes the alarm, signal, or call bell S, as shown more clearly in
the detail, Fig. 3. This bell may be of any size or form according to the dis-
tance at which the sound is intended to be heard. So soon as the detent or
tooth F is withdrawn from its notched disc E, the main spring or weight M,
as the case may be, causes the train of wheels and pinions A, B, C, and D,. to
revolve, and as the disc N which carries the pin or stud O rotates at a high
velocity, it causes the hammer R to vibrate rapidly and strike the bell S twice
for every revolution. The ordinary flyer or regulating vanes T are employed
for regulating the speed of revolution of the hammer actuating disc. The
ringing of the bell continues until the inclined projection I on the vertical
detent lever G drops into the succeeding one of the series of inclined notches a
in the disc K, whereupon a helical or other spring U, by acting on the lever
G, causes it to bring the detent F against the notch of the detent disc E,
thus stopping the motion of the wheelwork, and consequently arresting the
ringing of the bell till further required. The disengagement of the detent
lever G by the clock or timepiece is effected by the following arrangement of
mechanism:-The upper end of the detent lever G is prolonged upwards so as
to bear at b against the lower end of a disengaging lever V, which lever works
on a centre W, situate some little distance from its lower extremity. The.
upper end of the disengaging lever V forms a circle or ring X (shown clearly
in the detail,-Fig. 4). The axis or arbour of the minute wheel carries a
tappet wheel Y, provided with one or more tappets or projecting teeth c,.
according to the number of times in the hour which it is required to sound the
bell, for example, if it be required to sound the bell at any quarter of an hour,

page_text: then four tappets or teeth will be required on the tappet wheel, as shewn in.
Fig. 4. The teeth of this tappet wheel are intended to operate upon the upper.
end of the disengaging lever V, so as to push it to one side, and thereby cause
its lower extremity to force back the detent lever G, and release the detent F
from the notch in the disc E, thus setting in motion the train of wheels above
mentioned, and ringing the bell. In order to carry out this object, it is pro-
posed, according to one arrangement, to attach a curved spring d (Fig. 4) to
the circle or ring X, such spring being secured at one end e only, whilst the
other end is free to spring or play slightly, as shewn by the red lines, and
carries a laterally projecting pin f; g is a tooth or projection formed in the
middle of the spring d, immediately under but out of the range of the tappets
or teeth cof the tappet wheel Y so long as the spring d'in its normal condition;
as indicated by the black lines in Fig. 4, but brought within the range of such
tappets when the spring d is caused to assume the position indicated by the
red lines by the arrangement which I shall now proceed. to describe. In the
wheel h, in connection with the hour wheel,of the clock or timepiece, a circlo
of, say, 48 holes i is made, namely, 4 holes for each hour, if it be desired to
have the power of sounding the bell at any one or more quarters of an hour during
the 12 hours, but if such a minute division be not required, then the number
of these holes may be reduced accordingly. One or more pins (according to
the period or periods within the 12 hours at which the bell is to be sounded)
are fixed in the corresponding holes in the wheel h, and made to project there-
from, and as these pins come round they are brought in contact with the pin
f on the free end of the curved spring d; and deflect that spring into the posi
tion shown by red lines, thereby bringing the tooth or projection g within the
range of the tappets c of the tappet wheel Y; as one or other of these tappets.
comes round it meets the-tooth-g, and consequently pushes the end of the dis-
engaging lever V to one side, and releases the train of wheels which sets the
hammer in motion, such action continuing until the projection I on the
lever G falls into the next one of the notches a in the disc K, whereupon the
lever being drawn forward by the spring U, arrests the motion of the
mechanism; or according to a modified arrangement of the parts, a circle of, say,
48 holes, namely 4 holes for each hour, is formed in the dial or clock face and
a-stationary pin is inserted into one or other of these holes which corresponds
to the time at which the signal or alarm bell is to be sounded. The hour
wheel of the clock or a wheel or disc in connection therewith carries on its
face the curved spring d, which is fixed at one end, and carries at the opposite
end the small pin f, which enters a hole in the hour wheel or wheel or dise
connected therewith, and remains flush with the opposite face of that wheel

page_text: so long as the spring d, which inclines outwards towards the end at which the
pin is situate, is not pressed upon. Supposing it to be required to sound the
bell at the hour of four, the stationary pin is inserted into the hole correspon-
ding to that hour, and projects slightly through the dial. As the hour wheel
revolves it brings the curved spring d against the stationary pin, and as this
spring forms an incline plane, it will on passing the stationary pin be forced
inwards or against the hour wheel, and cause the pin on its free end to pro-
trude beyond the face of that wheel. This pin presses against the circle or
ring X on the end of the disengaging lever V, and deflects slightly the upper
end of that lever (which is made flexible for that purpose), so as to bring a
tooth or projection on the interior of the ring into the plane of revolution of
the tappet wheel Y; one of the teeth of this wheel will then push the disen-
gaging lever to one side, and by so doing will cause the detent lever to be
released from the notch in the detent disc herein-before referred to, the result
being the immediate ringing of the bell. The same effect is obtained each
time the curved incline spring passes a pin in the dial, any number of which
may be employed according to the number of times the bell is to be sounded
during the twelve hours. So soon as the tappet has acted the lever springs
back again out of the plane of revolution of the tappets, where it remains until
again acted upon by the piu in the end of the curved spring carried by the
bour wheel. It is proposed in some cases to establish an electrical communi-
cation-between two-or-more of these-apparatus,-so- that they shall all work in
concert, as is well understood by electricians.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion that I lay no claim to any of the
mechanical parts separately; but what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent, is,-
First, the general combination of mechanism for sounding alarm or signal
bells at any desired intervals of time, as heretofore described and illustrated by
the Drawings.
Second, the connecting of two or more such combinations of mechanism
by electric wires or conductors so that they may operate simultaneously.
Third, the combination of the lever G and its teeth or projections with
the notched discs E, K, and lever V, as and for the purpose herein-before
described.
Fourth, the combination in a clock or timepiece of the curved spring d,

page_text: pin f,-and tappet wheel Y with one-or-more revolving or stationary pins for
operating upon the disengaging lever V, as and for the purpose herein-before
described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, the First day of March, One thousand eight
hundred and sixty-five.
J. HENRY JOHNSON. (L.S.)