MENTS IN OR CONNECTED WITH MUSICAL BOX MECHANISM
Year: 1885

page_text: I GUSTAVE MERMOD of the firm of Mermod Frères of Ste Croix Switzerland
manufacturer do hereby declare the nature of my said invention for "IMPROVE
MENTS IN OR CONNECTED WITH MUSICAL BOX MECHANISM" to be as follows:-
'
In musical boxes as at present constructed it frequently happens that when
repairing a portion of little importance a part of, or the whole mechanism of the
regulator must be taken out or accidentally falls out of its bearings before the
mainspring has been uncoiled. The consequence is that the drum carrying
the pins suddenly begins to revolve at a high speed thereby damaging the said
pins and the teeth of the keyboard in such a manner that the repairing thereof in
many cases is impossible or at least very costly and can only be done by a
workman especially acquainted with such delicate work and such workmen are
only to be found in places where musical boxes are manufactured whilst most
other repairs in the mechanism can be executed by an ordinary watchmaker.
According to my invention the risk of the aforesaid accident is avoided.
My invention is composed of an automatic stop mechanism which in no way
influences the ordinary play of the musical box but suddenly stops the drum of the
same as soon as its turns at a high speed.
In the accompanying drawings figure 1 shews a side view of the mechanism of a
musical box provided with said stop mechanism. Figures 2 and 3 show two detailed
views of said stop mechanism hereafter referred to.
In all three figures the same letters refer to the same parts.
On the plate M are fixed the bearings of the axis N of the musical drum which
is acted upon by the barrel G containing the mainspring, which is wound up by
means of the crank H.
The wheel F which is fixed to the axis of the drum gives motion to the ordinary
train of the regulator J. The stop lever K intended to stop the music after every
air works as usual and all the aforesaid parts of the mechanism are of ordinary
construction and may vary at will without modifying the application or the action
of my safety stop mechanism.
The said stop mechanism is composed of a wheel A fixed upon the axis N or
upon the musical drum itself and of a click C the axis of which is fixed in the
bearing B.
The click C is provided with two projections o³ and c¹ and is also provided with
an arm & having a counter balance Ď.

page_text: If at rest the arm d. of the click C leans against a pin & fixed in the bridge B
by the action of the counter balance D.
The form and position of C is combined in such a manner that as long as the
musical drum turns at the ordinary rate of speed each tooth of A drives the click C.
from the position shewn in figure 1 to that shewn in fig. 2.
From the latter position the said click falls back to its original position by the
action of the counter balance D.
The described motion of Ơ has no influence upon the playing of the musical
works but should the musical drum happen to turn at an abnormal speed the safety
stop mechanism works automatically in one of the two following ways according |
as the click C is placed either in the position shown in figure 1. or in that shewn
in figure 2.
In the first case that is if the sudden increasing of the speed of rotation of the
musical drum happens whilst the click C is placed in the position shewn in figure 1.
one of the teeth of A will suddenly strike upon the projection c¹ of C and thereby
throw the projection in the position shown in figure 3 that is to say it will stop
the cylinder instantaneously. The whole mechanism will then remain at rest until
the click C is lifted by hand which must not be done before the damaged pieces
are repaired and put in place.
If the sudden increasing of speed of the musical drum occurs whilst the click C
is in the position shown in figure 2 the tooth a of A falls upon c with such a
rapidity that the counterbalance D has not time of withdrawing the click C so
that the musical drum is stopped instantaneously.
The click C may also be used to stop at will at any moment the musica!
mechanism by lifting the same by hand.

page_text: Improvements in or Connected with Musical Box Mechanism.
I GUSTAVE MERMOD of the firm of Mermod Frères of Ste Croix Switzerland
Manufacturer do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and by
the following statement:-
In musical boxes as at present constructed it frequently happens that when
repairing a portion of little importance a part of or the whole mechanism of
the regulator must be taken out or accidentally falls out of its bearings before
the mainspring has been uncoiled The consequence is that the drum carrying the
pins suddenly begins to revolve at a high speed thereby damaging the said pins
and the teeth of the key board in such a manner that the repairing thereof in
many cases is impossible or at least very costly and can only be done by a work-
man especially acquainted with such delicate work and such workmen are only to
be found in places where musical boxes are manufactured whilst most other
repairs in the mechanism can be executed by an ordinary watchmaker.
According to my invention the risk of the aforesaid accident is avoided. My
invention is composed of an automatic stop mechanism which in no way influences
the ordinary play of the musical box but suddenly stops the drum of the same as
soon as it turns at a high speed.
In the accompanying drawings fig. 1 shews a side view of the mechanism of a
musical box provided with said stop mechanism. Figures 2, 3, 4 and 5 show
detached views of said stop mechanism hereafter referred to. In all the figures
the same letters denote the same parts.
On the plate M are fixed the bearings of the axis N of the musical drum which
is acted upon by the barrel G containing the mainspring which is wound up by
means of the lever H.
The wheel F which is affixed to the axis of the drum gives motion to the
ordinary train of the regulator J. The stop lever K intended to stop the music
after every air works as usual and all the aforesaid parts of the mechanism are of
ordinary construction and may vary at will without modifying the application or
the action of my safety stop mechanism. The said stop mechanism is composed
of a wheel A fixed upon the axis N or upon the musical drum itself and of a click
or pawl C the axis of which fixed in the bearing B.
The click or pawl C is provided with two projections c¹ and c" and is also
provided with an arm d having a counter balance D. If at rest, the arm d of the
pawl C leans against a pin d¹ fixed in the bridge B by the action of the counter
balance D.
The form and position of C is combined in such a manner that as long as the
musical drum turns at the ordinary rate of speed each tooth of A drives the click C
from the position shewn in figure 1 to that shewn in fig. 2. From the latter
position the said click or pawl falls back to its original position by the action of
the counter-balance D.
The above described motion of C has no influence upon the playing of the
musical works, but should the musical drum happen to turn at a high speed the

page_text: safety stop mechanism works automatically in one of the two following ways
according to the position of the click C at the time either as shewn in fig. 1 or in
that shown in fig. 2.
In the first case, that is, if the sudden increasing of the speed or rotation of the
musical drum happens whilst the pawl C is placed in the position shewn in fig. 1,
one of the teeth of A will suddenly strike upon the projection c¹ of C and thereby
throw the projection in the position shown in fig. 3 that is to say it will
immediately stop the cylinder.
The whole mechanism will then remain at rest until the pawl C is lifted by hand
which must not be done before the damaged pieces are repaired and put in place.
If the sudden increasing of speed of the musical drum occurs whilst the click C
is in the position shown in fig. 2 the tooth a of A falls upon c¹ with such a rapidity
that the counterbalance D has not time to withdraw the click C so that the musical
cylinder is stopped instantaneously.
The click C may also be used to stop at will at any moment the musical
mechanism by lifting the same by hand. In the aforesaid mechanism each time
the projection c¹ of the pawl C falls from a tooth of the wheel A the tail end of C
falls against the pin d¹ and makes a noise. I obviate this objection either by
a covering of leather or other suitable material fixed on the tail end 'd of pawl C
'or by modifying the shape of projection c¹ as shewn at c¹¹¹ in Figs. 4 and 5. the
pin d and the leather aforesaid may be dispensed with. In this latter case while
the pawl C alters from the position shown at fig. 4 to that shewn at figure 5, that
is to say while one tooth a¹ of A leaves the projection cll and until the next tooth all
comes on the counter-weight D forces the pawl against the tooth a¹ of A with
its inclined plain c thus preventing the pawl from falling, the plain c¹¹¹ resting
against a¹ until a raises the pawl by coming against c¹¹.
Having now particularly described and ascertained the nature of this said
invention and in what manner the same is to be performed I declare that what
I claim is :-
The safety stop mechanism constructed and arranged substantially as and for the
purpose set forth.
Dated this fourth day of March 1886