DE102007006704A1 - Sound body for musical instrument, has multiple common plates integrated in bi-directional flow sensor, where airflow is measured by flow direction and pressure by flow sensor - Google Patents

Abstract

The sound has multiple common plates (401) integrated in bi-directional flow sensor. Every common plate demonstrates an air flow (101). Each airflow is measured by flow direction and pressure by a flow sensor. The totality of the parameters of the instrument for producing music is calculated. Certain codes of switching operation in the synthesizer are initiated. An independent claim is also included for a method for simultaneous production of a number of flow sensors in a plate as part of a sound body.

Description

1. State of the art

Known are musical instruments in the manner of a harmonica or accordion, where an internal body of sound from a number of channels is formed, wherein a number of such channels, an air flow is blown or sucked, so in each of the air flow perfused channels Depending on the pressure and direction of the air flow produces a specific sound becomes.

Known are sensors that control the pressure and / or the direction of a a channel through it Measure gases.

Known are strain gages on resistive and piezo-based. Known are printing methods for applying such or other sensors, and methods for the efficient assembly of such sensors with electronic chips, for their evaluation.

Known are digital encoding methods for music, e.g. B. by type MIDI standards, where a tone spectrum as well as certain temporal characteristics this spectrum (eg the attack of a note) are encoded, so that an electronic device in the manner of a PC sound card or a synthesizer that belongs to the respective code sound can play. Such methods allow, inter alia a single musician to record multiple soundtracks and the results to mix with each other; Furthermore, they allow an extremely compact Storage and transmission of sound data, and finally, this technology benefits from the Fact that the computing power of compact and cheaper processors, as well as their storage capacity, continue to rise.

Known are piano keyboards that produce the above codes directly, and provide similar sound results in conjunction with a synthesizer like a good piano, but much cheaper and smaller, and incidentally also produce the sound of completely different instruments can or completely artificial, Sound sequences modeled by suitable algorithms.

Known are methods for playing several instruments simultaneously by the same musician, being the combination of guitar and harmonica probably the most common is professionally used.

All generally could an electronic harmonica, which controls a synthesizer similar like a keyboard, the possibilities the musician considerably expand, and she could preferably be operated purely by blowing or suction.

2. Description of the invention

The The invention described below pursues the goal of an electronic To provide a sounding body, a number of channels that has air currents can be traversed, wherein each of these channels a bidirectional flow sensor which is for an air flow both its pressure exerted in the channel and its flow direction proves, and these two sizes each converted into codes and preferably converted by a synthesizer into audible tones.

The The invention achieves its object by a device according to claim 1, and a method according to claim 5. Further features of the invention are in the dependent claims recorded.

2.1 Description of a preferred embodiment

1 shows schematically and preferably how two strips ( 111 ) 112 ) on both sides on a recessed plate ( 401 ) are glued, and thereby a channel according to the invention is realized. Are 111 ) 112 ) made of plastic and with rectangular holes ( 10 ), wherein preferably the geometry and arrangement of the holes ( 10 ) in ( 111 ) and ( 112 ) is identical, so they are like in 1 indicated schematically, one above the other lie congruent and each form the inlet and outlet of an air duct in an inventive sound body, said two holes through a section ( 1 ) out ( 401 ) are separated from each other.

The cutout ( 1 ) forms the actual bidirectional flow sensor and is preferably in 2 schematized: ( 1 ) has a number of recesses, which are shown shaded and preferably designed as elongated holes, as well as a further, in 2 also shaded shown U-shaped recess having a tongue ( 2 ) in ( 1 ). In preferred variants, the holes ( 5 ) are omitted.

According to 2 meets, in the plan view shown, the air flow ( 101 ) perpendicular to ( 1 ) and presses the tongue ( 2 ) down out of the picture plane. Preferred is ( 2 ), and preferably additionally provided with steaming elements, that ( 2 ) does not swing. In other preferred situations, 2 ) about a rest position, which indicates the direction and flow velocity of ( 101 ) corresponds. Thus, by measuring ( 2 ) always the direction of the air flow ( 101 ) as well as the amount of 101 ) generated over or Negative pressure detectable. Preferably, this includes by ( 101 ) deformable part of ( 2 ) a strain gauge, z. B. from a metallized resistor ( 3 ) educated; this is when tongue down ( 2 ) so that its ohmic resistance increases. If ( 101 ) reverses, z. B. by passing through the opening ( 10 ) Air is sucked, so moves ( 2 ) in the 2 shown up and ( 3 ) is compressed so that the ohmic resistance of ( 3 ) falls. In the absence of an air flow ( 101 ) springs ( 2 ) in the of ( 401 ) plane spanned back.

It is preferably assumed that in ( 1 ) only the tongue ( 2 ) are significantly deformed, and that ( 1 ) at one of ( 101 ) non-deformable site a reference resistor ( 4 ), which is identical to ( 3 ) and the same environmental conditions -. Temperature and humidity - like ( 3 ), so that ( 3 ) at rest, ie without air flow ( 101 ) the same resistance value as ( 4 ), such that at a by ( 3 ) 4 ) And formed with a voltage V _o applied voltage divider, a voltage V _s ≃ V _0/2 occurs. Preferably, the (from 3 ) 4 ) formed voltage divider into a Wheatstone bridge integrated. In this arrangement, V _s follows the magnitude and direction of ( 101 ) pressure, and ( 1 ) thus realizes a bidirectional flow sensor.

Preferably, the tongues ( 2 ), when they vibrate, practically inaudible sounds, which are very quiet and / or lie outside the audible range.

( 401 ) is preferably formed from a photochemically workable glass plate, and has in the in 1 . 2 and 3 shown, preferred variant a number of flow sensors ( 1 ), which are each carried out the same way and have the same distance from each other.

Channels according to the invention with flow sensors ( 1 ) can be used not only for the electronic generation of a sound, but also preferably for issuing a command. These commands can be binary, by the blowing or sucking a specific hole ( 10 ), without taking account of the 10 ) generated pressure, each corresponding to a command; or they can be multivalued by For example, the amount of pressure applied by the airflow encodes various commands. Preferably, these command channels can be supplemented by corresponding keys, wherein a priority between the so-called issued by air flow and the key command can be agreed, and these keys are preferably designed as a rigid touch sensors.

3 now shows schematically and preferably how a number of such sensors ( 1 ) on ( 401 ) arranged side by side and with a 32: 1 analog multiplexer ( 204 ), where ( 204 ) after a fixed clock the individual output voltages V _{s of} the flow sensors ( 1 ) to the analog input of a controller provided with an A / D converter ( 209 ) switches through. Since the reading of a single strain gauge can be done in microseconds, one hundred or more flow sensors ( 1 ) can be measured almost simultaneously by a single controller.

Preferably calculated ( 209 ) from the sampled values a sequence of MIDI codes or commands for controlling switches, the z. B. be forwarded wirelessly or wired to a synthesizer.

Preference is given to the elements ( 1 ) as part of a common plate ( 401 ) produced by inexpensive methods of the prior art; z. B. can ( 401 ) first by printing and / or Aufmetallisieren with strain sensors ( 3 ) 4 ) as well as the required conductor tracks. Then ( 401 ) are provided with a protective lacquer and exposed, whereupon the in 2 shown pattern ( 401 ) are etched out; then ( 401 ) equipped with the necessary electronics and there are strips on both sides ( 111 ) 112 ) With ( 401 ), whereby the inventive sound body, z. B. as part of an electronic harmonica.

Of the invention orchestras may also, along with a bellows and associated, preferably imprinted Keyboards, part of a very inexpensive electronic accordion be.

2.2 Further embodiments of the invention

• 2.2.1 Other detection methods of the novel air streams are conceivable. a) it is conceivable that as in 4 schematically and preferably shown at a suitable distance above a tongue ( 2 ) one metal electrode each ( 205 ) which is connected via a resistor ( 207 ) is at ground, and wherein a surface ( 210 ) from ( 2 ) is made conductive, and is applied to a voltage V ₀ , and wherein ( 2 ) by a bridge ( 206 ) of conductive elastomer with ( 205 ) connected is. The footbridge ( 206 ) is preferably such that it has a lower compression and a higher resistance when stretched than at rest. Preferably, this resistor is part of a voltage divider, as in 4 shown, so that an output voltage is detected, the deflection of ( 2 ) corresponds. b) it is conceivable that ( 2 ) is electrically conductive, a high frequency alternating voltage leads, and these AC voltage capacitive or inductive in a static ( 401 ) coupled electrode, wherein the strength of this coupling with the deflection of ( 2 ) varies. c) it is conceivable that ( 2 ) has a microcoil, which by ( 101 ) is moved in an external magnetic field, so that via the voltage induced in each individual coil, the movement of a tongue ( 2 d) it is conceivable that the deflection of ( 2 ) is detected optically by either one with ( 2 ) connected light source when moving ( 2 ) is evaluated by a number of photodetectors, or ( 2 ) is designed as a light receiver, which evaluates a rigid light source, or the movement of ( 2 ) is evaluated with an optoelectronic device in the manner of a light barrier. e) it is conceivable that ( 2 ) has a piezoelectric element which controls the movement of ( 2 ). f) it is conceivable that each channel ( 1 ) comprises a valve realized with an elastic flap which, depending on the direction of an air flow ( 101 ) opens or closes. It is conceivable that in addition to such a valve, a thermal flow sensor is used, the z. B. detects the removal of heat from a defined resistance heated by a flowing gas. g) it is conceivable that 401 ) as in 5 shown schematically an all tongues ( 2 ) common line ( 208 ), which are parallel to the effective oscillation axis ( 211 ) of all tongues, and that all tongues ( 2 ) in a constant, preferably homogeneous magnetic field and preferably in the plane of ( 401 ) vertical magnetic field ( 7 ) lie. In this preferred variant, let each tongue ( 2 ) designed to oscillate mechanically at a unique frequency. In each case in (in 7 ) oscillating subelement ( 212 ) out ( 208 ), a partial AC voltage with this frequency and one of 101 ) induced air pressure dependent amplitude induced. Thus arises in ( 208 ) a sum AC voltage from which the movement of the tongues ( 2 ) can be reconstructed by signal analysis. The elements ( 212 ) from ( 208 ), characterized in that, firstly, they are in ( 7 ) and secondly parallel to ( 209 ) are.
• 2.2.2 It is conceivable that the bidirectional flow sensors while of playing the associated Instrumentes are calibrated continuously to z. B. temperature fluctuations, or to compensate for the wetting of a resistor or elastomer.
• 2.2.3 It is conceivable that the bidirectional flow sensor ( 1 ) with two mirror-symmetrical tongues ( 2 ) is realized, and by evaluating both tongue movements of the air flow ( 101 ) is detectable according to speed amount and direction.
• 2.2.4 Conceivable are flow sensors realized from materials other than glass ( 1 ). Preferably ( 1 ) are punched out of a polymer or metal foil or created by a laser processing method, and z. B. subsequently be provided with an insulating paint layer. Preferably ( 1 ) as part of a chemically or electrochemically deposited pattern. Preferably ( 401 ) be designed as Piezopolymerfolie, wherein the tongues ( 2 ) are provided on both sides with conductive electrodes, preferably by a printing process, so that at these electrodes the deformation of ( 2 ) becomes measurable.
• 2.2.5 Instruments according to the invention are also suitable for distance learning and / or self-learning. The instrument according to the invention can be part of a device which displays to the user the actually played music notes in comparison to those which he had to play by B the notes to be played are black, the notes actually played are red. A harmonica according to the invention can be provided with a number of electrodes on its end face, ie where it is touched by the lips and tongue, and these electrodes can be subjected to a low direct or alternating voltage such that the lips and tongue detect a stimulus pattern , which leads the player to the next sound to play. 2.2.6 The inventive sensor for multiple air channels is also suitable for outputting any codes, eg. B. in situations where the user does not want to or can not use his hands. Preference can thus z. B. be controlled in a complex music generator, which realizes an algorithm-based, only partially user-controlled composition process. 2.2.7 For sound reproduction a number of variants are conceivable. ( 209 ) may be provided with a wireless interface to a synthesizer, and preferably also to a number of switches, which z. B. control the synthesizer. Alternatively, in an instrument according to the invention, a sound chip and / or loudspeaker may be integrated with the sound body to form a single unit. Especially in a realization as a musical toy is conceivable that in the controller ( 209 ) is a simple sound synthesis, which is sent via an equally simple transmitter of lowest power on an adjustable radio frequency to generate a sound signal on any consumer radio.

3. Advantages of the invention

The Invention allows cost-effective production a pneumatically controlled body, z. B. as part of compact electronic harmonicas, which without moving elements after Kind of sliders or switches get along.

It is the flow sensor ( 1 ) containing plate ( 401 ), z. As part of a large glass plate or a large film, mass-produced in such a way that in the preferred embodiments, the production cost of a polyphonic instrument are not significantly higher than that of an instrument with fewer voices. Furthermore, the invention provides a way to build cheap, digital accordions.

Of the Main advantage over However, classical wind instruments lies in one through the synthesizer given extension of expressive possibilities for musicians, z. B. in the possibility for guitar players, to be able to serve a synthesizer instead of a mouth amonica.

Of Furthermore, such devices can be integrated into new services, which turn off on a music distance education.

Claims (6)

Sounding body as part of a musical instrument, which a number on a common plate ( 401 ) integrated bidirectional flow sensors ( 1 ), each containing a flow of air ( 101 ), each air stream ( 101 ) by a flow sensor ( 1 ) is measured according to the direction of flow and pressure, and the totality of these parameters is used to calculate the music to be produced by this instrument. orchestras according to claim 1, wherein certain codes switching operations in the synthesizer trigger. orchestras according to one of the preceding claims, the non-contact Keys included. orchestras according to any one of the preceding claims as part of an electronic Oral or accordion. Method for the simultaneous production of a number of flow sensors ( 1 ) in a plate ( 401 ) as part of a sounding body according to any one of the preceding claims. Method according to claim 5, wherein the flow sensors consist of a plate ( 1 ) are etched or punched out or worked out with optical methods, and printed with conductive patterns.