An Improved Safety Check for Musical Boxes, applicable also to other Mechanism.
Year: 1891

page_text: Date of Application. 26th June, 1891
Complete Specification Left, 19th Feb., 1592-Accepted, 9th Apr., 1892
PROVISIONAL SPECIFICATION.
An Improved Safety Check for Musical Boxes, applicable also to
other Mechanism.
1, JEAN BILLON-HALLER, of The Usine du Creux St. Jean, Geneva, in
Switzerland, Musical Box Manufacturer, do hereby declare the nature of this
nvention to be as follows:-
The purpose of safety-checks for musical boxes is to automatically stop the
rotation of the spring barrel if the transmission of the rotation from the teeth of
the spring barrel to the escapement be accidentally interrupted, as, for instance, by
reason of the breakage of a pivot of one of the movers of the regulator or escape-
ment; or in those musical boxes in which the rotation of the spring barrel is
transmitted to the escapement by means of an interchangeable cylinder, by
withdrawing the said interchangeable cylinder at the wrong moment.
Now, by means of my invention, I obtain this result in a very simple manner by
the mere combination of the teeth of the spring-barrel (or of any wheel which is
to be stopped in case of a sudden increase of its speed) with a worm gearing with
said teeth and bearing normally upon a resilient counter pivot, but, in case of
sudden increase of speed, upon a fixed point, thereby stopping its rotation and hence
the rotation of said wheel.
To effect this result the axis of one of the ends or pivots of the said worm bears
upon a counter-pivot acted upon by a spring, the strength of which is somewhat
greater than the pressure exerted by the teeth of the wheel upon the thread of the
worm to produce the rotation of the latter. As long as the speed of the wheel in
question is regular, the worm is pressed towards the teeth of the wheel by the
aforesaid spring and the rotation of the wheel causes the rotation of the worm
which has no other resistance to overcome than the friction of its ends or pivots in
their holes, but if a sudden increase of speed of the wheel be inadvertently
produced the pressure of the teeth of the wheel upon the thread of the worm will
also be suddenly increased and the axis of the worm will then overcome the pressure
of the spring acting upon the counter pivot and will consequently displace the worm
axially. Now said worm being provided with a shoulder or projection, which.
when a sudden increase in speed of the wheel occurs, comes into contact with a
fixed surface, or with a catch of any suitable kind arranged so as to stop the
rotation of the worm when such contact takes place, the stoppage of the worm and
of the wheel taking place as soon as the aforesaid axial displacement of the worm
occurs.
This safety check may be used for stopping and starting musical boxes. The
stopping being effected by pressing upon a button at the outer end of the worm, and
the starting by slightly raising said button.
This construction of safety check and stopping mechanism may be used in any
mechanism where it may be useful to stop a wheel in case of a sudden acceleration
of its speed.

page_text: COMPLETE SPECIFICATION.
An Improved Safety Check for Musical Boxes, applicable also to
other Mechanism.
I, JEAN BILLON-HALLER, of The Usine du Creux St. Jean, Geneva, in
Switzerland, Musical Box 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, reference being had
to the accompanying drawings and to the letters and figures marked thereon, that
is to say -
The purpose of safety checks for musical boxes is to automatically stop the
rotation of the spring barrel if the transmission of the rotation from the teeth of
such barrel to the escapement be accidentally interrupted, as for instance by the
breakage of a pivot of one of the movers of the regulator or escapement; or in
those musical boxes in which the rotation of the spring barrel is transmitted to the
escapement by means of an interchangeable cylinder, as is the case in the musical
box shown by way of example in the accompanying drawings, by withdrawing the
said interchangeable cylinder at the wrong moment.
Now, by means of my invention, I obtain this result in a very simple manner by
the mere combination of the teeth of the spring barrel (or of any wheel which is
to be stopped in case of a sudden increase of its speed,) with a worm gearing with
said teeth, and bearing normally upon a resilient counter pivot, but in case of
sudden increase of speed, upon a fixed point, thereby stopping its rotation and hence
the rotation of said wheel.
To effect this result, the axis of one of the ends or pivots of the said worm bears
upon a counter pivot acted upon by a spring, the strength of which is somewhat
greater than the pressure exerted by the teeth of the wheel upon the thread of the
worm to produce the rotation of the latter. As long as the speed of the wheel in
question is regular, the worm is pressed towards the teeth of the wheel by the
aforesaid spring, and the rotation of the wheel causes the rotation of the worm
which has no other resistance to overcome than the friction of its ends or pivots in
their holes, but if a sudden increase of speed of the wheel be inadvertently
produced, the pressure of the teeth of the wheel upon the thread of the worm will
also be suddenly increased, and the axis of the worm will then overcome the pressure
of the spring acting upon the counter pivot, and will consequently displace the worm
axially.
Now said worm being provided with a shoulder or projection which, when a
sudden increase in speed of the wheel occurs, comes into contact with a fixed surface,
or with a catch of any suitable kind, arranged so as to stop the rotation of the
worm, when such contact takes place, the stoppage of the worm and of the wheel
takes place as soon as the aforesaid axial displacement of the worm occurs.
The accompanying drawings illustrate an application of the above described
safety check.
Fig. 1 is a plan and Fig. 2 an elevation of a musical box provided with my
improved safety check.
Fig. 3 is a front elevation, partly in section, of the safety-check on a larger
scale, and
Fig. 4 is an end view of the spring barrel combined with said safety check.
In all the figures similar letters of reference indicate corresponding parts.
A is the spring-barrel containing the main spring of the musical box. B is the
interchangeable cylinder, the pinion 6' of which is acted upon by the teeth of the
spring barrel A, while the teeth 62 act upon the escapement or regulator C. D is
the worm forming the safety-check and carried in a bearing E fixed to the base
plate F. It is placed tangentially to the teeth of the spring-barrel with which it
gears. The upper pivot d', of the worm D, is long enough to permit of its sliding

page_text: axially in its hole. The lower pivot, of the worm D, bears upon a counter
pivot g acted upon by a spring 9. The worm D is furthermore provided with a
shoulder d* which is caused to bear upon a corresponding surface e of the bearing E,
when the worm D compresses the spring g. The friction caused by the contact of
the shoulder d upon the surface e is sufficient to stop the rotation of the worm and
to thereby cause the spring barrel A to be stopped at the same time.
This stoppage will take place for instance if (whilst the movement is playing)
the cover of the bearing which carries the pivot of the interchangeable
cylinder B be opened, as shown by the dotted lines in Fig. 1. In such a case the
cylinder would be thrown out of its bearing and the main-spring would revolve the
spring barrel with great velocity and injure the mechanism, should it not be stopped
at once by the safety check.
When the cause of the accident is suppressed, for instance when in the above
mentioned example, the cylinder B and the cover H of its bearing are restored to
their respective places, the safety check may be relieved. This is effected by
turning the button D* of the worm D until the shoulder dx is removed from the
surface e.
This safety check may be used for stopping and starting musical boxes. The
stopping being effected by pressing upon the button D and the starting by slightly
turning said button D as described above.
This construction of safety check and stopping mechanism may also be used in
any other mechanism where it may be useful to stop a wheel in case of a sudden
acceleration of its speed.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A safety check for musical boxes, also applicable to other mechanism, and
capable of working as a stopping and starting mechanism whereby the stopping of
a wheel, in case of its sudden acceleration of speed, is effected, consisting in the
combination with the wheel, which is to be stopped, of a worm gearing with such
wheel and having one of its pivots supported by a resilient counter pivot and
provided with a shoulder or projection which comes into contact with a fixed point
on the mechanism when the worm is axially displaced, substantially as herein set
forth.
2. In musical boxes, the combination with either of its gear wheels of a worm D,
the pivot of which bears upon a counter-pivot g* which is acted upon by a
spring, substantially as described and shown, and for the purpose set forth.
Till: 10
1000
ERNEST DE PASS,
Chartered Patent Agent,
78, Fleet Street, London, and 6, Victoria Street, Nottingham,
Agent for the Applicant.