IMPROVE- MENTS IN MACHINERY FOR CONVERTING STRIKING CLOCKS INTO CHIME CLOCKS
Year: 1879

page_text: LETTERS PATENT to Antoine Léon Cornu, Watchmaker, of 3, Bennett Street,
Fitzroy Square, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN MACHINERY FOR CONVERTING STRIKING CLOCKS INTO CHIME
CLOCKS."
Sealed the 30th September 1879, and dated the 3rd April 1879.
PROVISIONAL SPECIFICATION left by the said Antoine Léon Cornu at the
Office of the Commissioners of Patents on the 3rd April 1879.
ANTOINE LÉON CORNU, Watchmaker, of 3, Bennett Street, Fitzroy Square, in
the County of Middlesex. "IMPROVEMENTS IN MACHINERY FOR CONVERTING
STRIKING CLOCKS INTO CHIME CLOCKS."
My Invention consists of a system of machinery whereby I can convert ordinary
striking clocks of any kind or size into chime clocks with great saving of cost.
The machinery consists of a barrel and internal spring communicating with a
cylinder, which is provided with projecting points.
The revolutions of the cylinder are regulated by a wheel, with indentations at
irregular distances, or by a rack.
The points on the surface of the cylinder work upon hammers, which when put
into motion strike upon bells or gongs and cause the chimes, the tunes being created
by the position of the projecting points.
The cylinder makes by my system one revolution per hour instead of two as in
other clocks, and so causes less friction and is less likely to get out of order.
In carriage clocks I can also introduce steel combs in the place of the cylinders.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Autoine Léon Cornu in the Great Seal Patent Office on the 2nd
October 1879.
ANTOINE LEON CORNU, Watchmaker, of 3, Bennett Street, Fitzroy Square, in
the County of Middlesex. "IMPROVEMENTS IN MACHINERY FOR CONVERTING
STRIKING CLOCKS INTO. CHIME CLOCKS."
My Invention has for object improvements in converting ordinary striking clocks
into chime clocks, with gongs, bells, alarums, and the like.
For this purpose I have devised a chime mechanism, which is separate from
the clock movement, but which can be applied or adapted to the striking movements
now in use.
The mechanism consists of a barrel and internal spring communicating with a
cylinder which is provided with projecting points. The revolutions of the cylinder
are regulated by a wheel -with notches or indentations at irregular distances, or by
a rack.
The points on the surface of the cylinder work upon hammers, which when put
into motion strike upon bells or gongs and produce the chimes, the airs or tunes
being created by the positions of the projecting points.
By my system the cylinder makes one revolution per hour instead of two as in
other clocks, and thus causes less friction and less likelihood to get out of order.
It can also be applied to carriage-clocks, the chimes or airs being produced with
bells or other striking arrangements, such as steel combs, as in musical boxes.
I now proceed, with reference to the annexed Drawing, to describe more particu-
larly my said Invention.
The upper portion represents the movement of an ordinary clock; it is shewn
from the side of the dial, which is however here removed for clearness, as are also
those pieces which are unnecessary to the description of the Invention.
The lower portion, represents the movement for effecting the chimes; it is seen
from the same side as the clock movement.
I will first describe the mechanism of the chime movement, and then the means
of combining or connecting it with the clock movement. It is composed of two
plates Z, which are connected together by pillars p, p, only one of these plates is
seen in the Drawing. Between these plates a barrel R is mounted on an axis b;
one of the faces of this barrel carries a toothed wheel D, which drives the inter-
mediate arbor a by means of the piuion a*; this intermediate arbor also carries a
wheel C, which drives the drum T by means of the wheel E which is mounted on
its arbor e. This wheel C also drives another arbor d by means of the pinion d* ;
it is this arbor which drives the fly V by means of the wheel H and the endless
screw S.
The cylinder or drum T is provided with notches x1, x2, x³, and x, and effects
one revolution in an hour, whereas in other chime movements it effects two; it
carries on its circumference pin points (not seen in the Drawing) which are arranged
thereon according to the chime or air to be produced; these points in their revo-
lution raise the strikers or hammers G, which in falling against the bells or
gongs K, of which there may be any number, produce the chimes or air by the
movement of the clock.
For this purpose the centre wheel J, which usually carries one or two studs
according to the movements to be effected for striking the hours or hours and half
hours carries in this instance four pins or studs g,g, g,g, for the purpose of obtaining
a chime every quarter of an hour. These pins raise the lever L, to which is fixed
the connecting rod M which connects the lever L aforesaid with the lever L' of the
chime movement. The lever L¹ carries a pin f which pushes the small branch l³ of
the lever L' and displaces this latter, which kept the drum and the fly stopped by

page_text: means of the pin h resting in the notch a¹ of the drum T, and the projection s
against which the arm 7 of the arbor of the fly abuts, which thus being disengaged
is set in motion by the impetus of the barrel; but it can only make a partial revo-
lution, the arm coming against the projecting portion o, which only allows it to
escape when the lever L' falls from its normal position.
During this time the notch of the lever Ĺ³ descends on the pin h to hold the
lever L² until the stud g' corresponding to the notch x¹ of the drum in its rotation
raising the lever L'; this one will also touch the stud h' of the lever L³, which will
be raised, and will thus release the lever L2, which, under the action of the spring Y,
will engage in another notch of the drum by again stopping the arm 7 of the fly
till the succeeding quarter of the hour.
I have described how the throwing out of gear of the chime movement is effected,
but if the movement for striking the hours were not modified it would strike at
every quarter of an hour, therefore I fit on the minute wheel N a stud n which
only acts every hour on the detent lever L, which also retains the locking or ballast
wheel O. But on the other hand if the mechanism were left in this state the
striking of the hours would take place at the same time as the chiming, therefore
I place another lever L behind the movement to hold the stop-wheel W until the
chimes of the four quarters have struck and the stud m on the drum T releases the
stop wheel by raising the lever L' which pushes the lever Lº, it is only then that
the hours will strike.
As I have now described the means of obtaining the striking and the chiming
by this special arrangement, which said arrangement can always be employed
whatever be the respective arrangement of the movements, I will now describe
how I effect the winding up of the chime.
For this purpose I add to the clock movement an arbor r with a stop-click t and
a sprocket-wheel u. On the arbor b of the barrel is another similar pulley ux,
which is connected to the first named one by a chain v passing over a tension
arm P. In this way the three winding squares are placed in the dial, thus
obviating the necessity of piercing the case in the lower part whilst giving it a
better appearance. However, in certain cases, it might be preferable to wind up
the chime barrel direct by its arbor or axis b.
In some cases I prefer to turn the chime movement upside down and to connect
together the plates of the two movements by a lap joint or other suitable joint,
and the arbors r and b being thus brought nearer together can now be connected
by one or more wheels, thus dispensing with the endless chain.
Having now described the nature of my said Invention, and in what manner the
same may be performed, I declare that I claim,―
First. The system or arrangement of mechanism, substantially as herein
described and shewn, for producing chimes, and in which the drum or cylinder of
the chime movement effects only one revolution in an hour, thus permitting a tune
or air to be played.
Second. The adaptation or application of my system or arrangement of mechanism
to any ordinary striking clocks as set forth, whereby I am enabled to convert &
striking clock into a chime clock, the said chime movement forming no part of the
clock movement as is now usual, but being separate therefrom for the purpose set
forth.
In witness whereof, I, the said Antoine Léon Cornu, have hereunto set my