Improvements in Signalling or Alarm Sounding Apparatus for Vehicles.
Year: 1898

page_text: Date of Application, 26th Aug., 1898-Accepted, 4th Mar., 1899
COMPLETE SPECIFICATION.
Improvements in Signalling or Alarm Sounding Apparatus for
Vehicles.
We, GOTTLIEB PROBST-SCHILLING, of Nonnenweg 35, Basel, Switzerland, Banker,
and HANS STICKELBERGER, of 34/36, Leonhard Strasse, Basel aforesaid, Engineer
and Patent Agent, 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 and accompanying drawings:-
Our said invention relates to improvements in signalling or alarm sounding
apparatus for vehicles of various types. The signalling or alarm sounding
apparatus which forms the subject matter of this invention is based upon the use
of musical tones and chords uniformly continuous and agreeable to the ear, like
those emitted by a siren, as contrasted with the exceedingly unpleasant shrill
notes of a bell, trumpet, whistle or the like. The said apparatus serves moreover
to indicate the rate of the speed of the vehicle by means of the corresponding pitch
of the siren.
On the accompanying drawings this apparatus and its various accessories are
exemplified by a number of illustrations.
Fig. 1, shows a bicycle on which the siren S fitted to the ball head L by means
of the clamps j can be actuated by a cord-transmission Z from the axle of the
front wheel R and receives its supply of air from a van V similarly actuated.
A suitable appliance may be introduced enabling the tension of the two trans-
mission cords z to be regulated so as to connect or disconnect the siren.
The siren itself is shown enlarged in Fig. 2. Here an airpipe o proceeding
On the cover m¹ a
from the van V (Fig. 1) terminates in a cylindrical shell m.
disc is placed, this disc revolving on an axle i supported in the cover and fitted
with a cord-pulley k. Both the cover and the disc are provided with holes or
When the disc is caused to revolve its
apertures corresponding to each other.
holes pass alternately over the holes and the blanks or bridges between the holes
of the cover; in one case the current of air escapes freely, in the other it is inter-
cepted. The more rapid the revolutions of the disc, and the greater the number of
its holes, the quicker the vibrations of air will succeed each other. These periodical
vibrations or pulsations create waves of sound producing the effect of musical
tones or notes. The disc n¹ (Fig. 4) as also the cover m¹ has 5 rows of perforations
with 20, 16, 12, 8 & 4 holes. When the cycle is set in motion with sufficient rapidity
to produce say 22 revolutions per second of the cord-pulley k, and
the disc n this will give for the outer series of holes 20 × 22 =
separate pulsations resulting in a distinctly audible note corresponding
to the tone a¹ (of the third octave). For the other series of holes
the notes are f¹, c', f, F. The greater the speed, the higher will be the pitch of the
chord produced, whereas when the speed is reduced, the chord will sound deeper
in tone, indeed some notes may become quite inaudible, as for instance when the
inner series of holes in the disc with 4 revolutions only emits 16 pulsations which
are incapable of producing a musical note perceptible to the ear.
440
We may also place upon the cover m³ of the shell m a disc n² (Fig. 5) secured to

page_text: will cause these tongues to vibrate whenever they pass the apertures 12; they too,
in like manner (all together or successively), emit a sound. Here again a com-
parison of note or chord of the tongues with the chord of siren will serve to ascer-
tain the speed. The rim or annular lip serves to impede the intrusion of dirt or
dust in the holes. By means of the rod s the siren may be brought into contact
with the wheel-tyre K or removed clear of it, in other words thrown in or out of
action.
Fig. 10, represents a modification of types Figs. 7 & 8. Here we have two similar
siren shells which can be made to revolve by means of a common friction-wheel r
resting of the wheel R and rotating round the axle. The axle is supported
on the arms J, J2 which latter are arranged to slide on the ball-head or frame L
when required. The arrows indicate the direction of the air-currents.
In the type illustrated by Figs. 11 and 12, the siren has a round shell t attached
to the ball-head L by means of clamps j¹ with a shaft passing through its geometrical
axis capable of revolving and supported at 3 on a clamp ja attached to L, and in
front at on a bridge connecting the two clamps j. To this shaft are fixed a
number of vanes w inclined at a certain angle. Behind the fan or air-propellor wis
a partition t¹ smaller in diameter than that of the shell t. The perforated back t²
of the shell is separated by a chamber from the partition t¹; finally, close behind
the back t², and perforated similarly to the latter, is a disc u attached to the shaft i³.
The propulsion of the vehicle gives rise to a current of air which sets in rotation
the fan or air propeller w and with it the shaft 3 and the disc u; at the same time
the air penetrates into the shell t where it is forced by the fan w into the chamber
or space between the partitions t¹ and the back t2, from which it is ready to escape,
whenever the openings in u coincide with those in t3, thus producing a note or a
chord as the case may be.
The above examples by no means exhaust all the possible methods of working
a siren by this invention. The choice of various methods is to be determined by the
class of vehicle which it is intended to provide with a signalling or alarm apparatus.
We might apply a suitably designed siren to a motor-car (automobile).
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:-
1) A signalling apparatus for vehicles consisting of a siren which can be worked
by the motion of the vehicle in such a manner that its pitch shall correspond in
a given ratio to the speed of the vehicle for the time being substantially as herein
described and shown.
2) A signalling apparatus according to Claim 1), the siren of which is connected
with a fan or air-propellor, which, being made to rotate by the current of air
produced by the motion of the vehicle, serves not only to work the movable parts
of the siren, but also supplies the air necessary for developing the sound sub-
stantially as described and shown.
3) A signalling apparatus as described in Claim 1), the siren of which is con-
nected with a special blowing contrivance worked by the vehicle, for the purpose
of creating a continuous current of air to effect the sounding of the siren sub-
stantially as described and shown.
4) A signalling apparatus according to Claim 1), in which the siren, with a
pitch varying in proportion to the rate of speed, is connected with a signalling
apparatus with an unvarying pitch, in order to facilitate an estimate of the rate
of speed substantially as described and illustrated.
5) A type of signalling apparatus on the principle of Claims 1).& 4), in which
a whistle of any kind is introduced at the air-supply-pipe substantially as described
and shown.
6) A type of signalling apparatus on the principle of Claims 1) & 4), in which
one of the discs is provided with an indefinite number of spring-tongues and the
other disc with a corresponding number of apertures, in which case a note or sound

page_text: is emitted every time a tongue passes over one of the apertures substantially as
described and shown.
7) A signalling apparatus on the principle of Claims 1) & 2), in which one of the
perforated discs (u) rests on a shaft (3) fitted with an air-propellor (w) and in
driving is caused by the generated air-current to revolve in front of the stationary
perforated disc (2), whereby the compressed air, produced in the shell (t) by the
meeting together of the disc-openings, passes through the latter and emits the
sound substantially as described and shown.
8) A signalling apparatus on the principles of Claims 1), 4) & 6), in which the
circular siren (like a top), capable of rotating round an axle fitted with a perforated
disc, contains another perforated disc capable of rotating with it, through the
openings of which a current of air can escape every time they encounter the open-
ings in the disc fitted to the said axle substantially as described and shown.
9) A type of signalling apparatus as described in Claims 1), 3) to 6), and 8), in
which the movable parts of the siren are worked by means of suitable transmission-
organs from one of the axles of the vehicle substantially as described and shown.
10) A type of the signalling apparatus described in Claims 1), 3) to 6), 8) and 9)
in which the movable parts of the siren are worked by means of friction-roller
adapted to one of the wheels substantially as described and shown.
11) A type of the signalling apparatus described in Claims 1), 3) to 6), S) and 9),
in which the working of some of the movable parts of the siren is effected by means
of suitable transmission-organs from one of the axles of the vehicle, and that
of the other movable parts by means of a friction-roller substantially as described
and shown.