IMPROVEMENTS IN MUSICAL TOPS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Frank Wirth at the Office of the
Commissioners of Patents on the 5th October 1882. A communication from
Max Dannhorn, a person resident at Nuremberg in the Empire of Germany.
FRANK WIRTH, of the firm of Wirth and Company, Patent Solicitors, at
Frankfort-on-the-Main, in the Empire of Germany "IMPROVEMENTS IN MUSICAL
TOPS [A communication from Max Dannhorn, a person resident at Nuremberg
in the Empire of Germany.]
"
This invention relates to improvements in musical tops or gyrophones.
According to the said invention the top or gyrophone is constructed as follows,
that is to say, I provide a metal case which may be made in two or more pieces.
In the upper part of the said case is a metal plate and in the lower part is another
metal plate both rigidly connected with the said case. The lower plate is provided
with a number of reeds placed in a circle and close to one another which are
caused to play one or more tunes according to the size of the top. The said case
between the upper plate and the reed plate is provided with a number of apertures
and the lower part of the said case is also provided with apertures. In a frame
secured to the upper plate is arranged the main spindle provided with a driving
pinion which gears with two toothed wheels. At a short distance from the edge,
these wheels have a rib of about 5 or 6 millimetres in height and the said wheels
are capable of rotation upon pins or studs fixed to the upper plate, to which are
also secured pins connected with the axes of the said toothed wheels by means of
india-rubber or other elastic bands passing round one end of the said ribs whereby
the said bands are stretched.
The elastic bands may, if preferable, be replaced by a spiral spring fastened at
one end to the axle and at the other to a pin which may be shifted from right to
left and vice versa and fixed by means of a screw. The main spindle is provided
at its lower end with a clutch which engages with a similar clutch contrived in a
circular casing or tube. The said casing or tube, as also the main spindle, is partly
enclosed by an envelope or outer tube which is fastened to the reed plate, and the
lower part of the outer case.
In the said casing or tube is screwed a pin capable of moving up and down in
a slot in the said outer tube. A spiral spring presses the said casing or tube

page_text: downward and out of the envelope or outer tube until the clutches ongage with
each other. Another plato is fixed to the main spindle, which plate covers tho
openings to the reed plate, and is provided with a slit which, when the said plate.
turns round, passes over the whole of the reeds in the reed-plate. The inain
spindle terminates at its upper part in a square and the driving gear.or mechanism
which rotates the said spindle can be wound up by means of a key. Through the
winding up and consequent rotation of the said main spindle, the driving pinion,
and with it the toothed wheels, are set in, rotation and thereby the elastic bands.
The said clutches engage with one another when the winding up is performed,
and prevent the unwinding of the said inechanism until required.
When the said mechanism is wound and the top is caused to spin the said
spiral spring is compressed, the ratchet wheels separate and the main spindle
through the stretched elastic bands and the driving pinion, is set in rotation and
with it the plate provided with the slit in a direction opposite to that of the top.
As the said slit passes over each reed of the reed plate it causes cach to be sounded,
because, through the rotation of the top a current of air is created, entering
through the apertures in the lower part and leaving by the apertures at the upper
part of the case. Through this current of air each reed as it comes under the slit
of the plate is sounded and through the sounding of the several reeds at different
periods a tune may be played.
By means of a sail fastened beneath the upper plate the force of the current of
air is increased. In a modification of this invention the main axle is in two parts;
the under part is secured to the under part of the outer casing and the upper part
is also fixed at the upper end in a bearing and at the lower part in a recess
made in the reed plate.
In another modification, the axle is also made in two parts; the lower part is
made fast to the outer casing while the upper part is fixed at its upper end in a
bearing and at its lower end in a socket in the lower part of the axle. The
upper part of the axle then rotates upon the lower and has attached to it a pear-
shaped casing. This latter is open at its lower part and circular, but narrows
upwards until it forms a slit whose size corresponds to the size of the reed openings
in the reed plate.
Through the motion of the top, the air enters the openings in the pear-shaped
casing and leaves it through the said slit. Thus each reed as it comes over the
said slit is made to sound. The construction of each modification is in other
respects similar to that herein before described, with the exception that the winding
arrangement is dispensed with as when the top is made to spin the inner driving
gear is wound up in consequence of the centrifugal force.