FR2576442A1 - DEVICE FOR IMPROVING THE SOUND AND WEIGHT OF ACCORDIONS AND BANDONEONS AS WELL AS GUITARS, VIOLINS, STRING DOUBLES, CLARINETS, PIANO, FLUTES, BATTERY - Google Patents

Abstract

The device for improving the sound of accordions and bandonions is characterized in that it is comprised of materials having a minimum hardness of 70 shores D, particularly of carbon fibre or other fibre compounds, or of composites (which may be coated for decorative purposes with materials having a lower or higher hardness), comprising platelets (1) arranged in the facing of the chest (4) by means of fixing elements (2). The chest (4) is fixed to an edge inside the case of the accordion (6) by screw elements (8). The sealing between the valves (12) and the plate on which they are bearing is improved by one or two lips (14), (15).

Description

 The present invention relates to a device for improving the sound of the accordion and the bandoneon, reducing their weight, improving the fixing and sealing of the pads, box springs, and the sealing of the valves.

 The manufacture of accordions and bandoneons, made of wood and thermosetting (plastic) restores sounds that can be improved as well as the attachments and insufficient sealing of the joints, and results in too great a weight.

 The invention makes it possible to remedy these drawbacks. The production of these inslruments in materials with a minimum hardness of 70 shores D, in particular carbon fiber or other fiber compound with resin and hardener, or in composite, of higher hardness. wood and plastic; which allows the vibrations produced by the blades to propagate in the parts produced, and to obtain a greater frequency-sound, as well as an increase in wavelengths, and more defined sounds.

 The whole instrument can be made or only a few parts. The average hardness of the carbon fiber is 85 to 90 shores D. The weight decreases for the parts produced by about 50 to 80%. This allows the user to have a greater musical expression, with less effort, a lighter instrument, to play longer, to tire less.

The hardness of the materials currently used is as follows
- from 60 to 70 shores D for thermosets (plastics) - from 55 to 65 shores D for beech, fir, etc.
The hardness of the carbon fiber compound is about 85 to 90 D shores. This material therefore has a significantly higher reflectance of acoustic waves. Indeed, the hardness of carbon fiber is about 31% higher compared to a thermosetting (plastic) and 42 v compared to wood.

The speed of sound (speed in meters per second) being increased for equal duration of vibrations (t), we will perceive a greater frequency-sound (frequency ~~ Nb of vibrations double per second), as well as an increase in lengths waves (X in meters) see formulas 1 and 2.

(t = duration of a double vibration in seconds
The methods of fixing the plates to the bed base are currently produced either by nails or by wax around the perimeter. These fixings are insufficient to allow the vibrations produced by the blades to propagate completely in the bed base. In addition, with wear, the nails withdraw slightly or the wax dries and peels off. In both cases this accentuates the loss of sound, due to the decrease in pressure between the pads and the bed base.

 The present invention will be better understood by referring to the figures.

 - Figure 1 showing a view of the box spring inside the accordion case.

 - Figures 2 - 3 - 4 different methods of fixing and making the plates.

 - Figure 6 the known sealing mode.

 - Figures 7 - 8 the seal between said plates (1) and the box spring (4) and the embodiments.

 - Figure 9 a side view of a key assembly with the known sealing mode.

 - Figures 10 - It - 12 realization of the sealing of the valves.

 The extension of the plates (1) makes it possible to find the space required for the location of a certain number of holes or lights for the fixing means (2) which can be in particular screws, bolts or nuts, to increase the pressure of tightening between said plates (1) and the bed base (4). The increase in this pressure promotes the propagation of vibrations emitted by the blades (3) fixed on the plate (1) in the bed base (4). This set consisting of (1) + (2) + (3) + (4) being made more homogeneous, there is much less loss of sound.

 The fixing system will be improved depending on whether at least 2 screw elements (2) are placed in figure 1 or 4 * screw elements (2) in figure 2 or 6 screw elements (2) in figure 3 or 8 screw elements (2) in figure 4 To keep the known plates (1) it is possible to insert at least 2 screw elements (2) at the edge thereof or in lights, so that the heads or; nuts (5fr come to bear on the periphery of the plates (1) or in the slots.

 The implantation of the screw elements (2) could be screws: transverse figure 5 solution 1 or blind figure 5 solution Z 'or bolts figure 5 solution 3.

 In the traditional sealing system of the plates (1) on the bed base (4), these were fixed directly to the "flat" joint in FIG. 6. This caused on the one hand, leaks at the joint level, and this reduced the propagation of vibrations produced by the blades in the base (4) and the body (6) of the instrument; on the other hand, a displacement of - the plate (1) at the time of fixing could occur This displacement caused the fact that the blade (3) or the skin (5) rubbed on the bed base (4) and annihilated their vibrations.

 To remedy this state of affairs, this invention proposes a counterbore in the bed base (4) in order to center the plate (i) and therefore to avoid its displacement.

 In addition, the seal between the plates (1) and the som, mier (4) is ensured by 7 or 2 lips (10) or by: -a seal (it) made of rubber, plastic, felt or other flexible material (closed cell) which allows contact of the pads (1) with the bed base (4).

 The known system for fixing the box spring (4) to the accordion box (6) is provided by aluminum plates, which are fixed by screws on the edge of the box to press the legs of the box spring. This binding has an average efficiency for the propagation of vibrations, sealing as well as its displacement.

To improve it, it is necessary to cause a border (7) inside the accordion case (6) over the entire perimeter or in a punctual manner at the location of the legs of the box spring (4). so that it is intimately linked in support with its edges (7) using one or two screws (8), or to keep the known system, add one or two screws to increase the clamping pressure - between the - pads and legs of the box spring
In the traditional known system of key assemblies, the seal was obtained by a fiber joint (felt type) with skin, Figure 9 (13)> The invention improves this seal by clinking wedging between the valves (12) and the plate on which they have; ; well, 1 or 2 lips which have the effect, by decreasing the bearing surface, of increasing the sealing pressure while maintaining the same sealing pressure, while maintaining the same pressure for using the button.

Claims (11)

 1) Device for improving the sound and the weight of the deons and bandones, characterized in that it consists of materials with a minimum hardness of 70 shores D, in particular carbon fiber, or other fiber compounds, or composites (can be covered for decoration, of materials-of a lower or higher hardness), comprising plates- (i) placed in the counterbore of the bed base (4) using the fixing means (2). The box spring (4) will be fixed on a border inside the accordion case (6) by screw elements - (8) The seal between the valves (12) and the plate on which they rest will be improved by 1 or 2 sèvres (14) (15).  2) Device according to claim 1) characterized by counterbores: dans- the base (4-) to center the plates (1) and prevent its displacement  3) Device according to claim 1) characterized by an extension and enlargement. inserts, which makes it possible to find the space necessary for screw elements (2) screws or bolts with nuts.  4) Device according to claim 1) to keep the known plates, characterized in that are inserted at least 2 screw elements-- (screws or bolts) (2) at the edge thereof so that the heads or nuts come to bear around the edges of the plates (I-) or lights.  5) Device according to claim 1) characterized in that the means for fixing the plates (1) consist of at least 2 screw elements (2): screws or bolts.  6) Device according to claims 11) - 3) - 4) - 5), characterized in that the screw elements (screws or bolts) (2) which hold the plates (4) can be screwed dirty into the plates (1 ) in opposition figure 5 solution 1, or blinds figure 5 solution 2, or transverse bolts with nuts figure 5 solution 3.  7) Device according to claim 1) characterized by the superposition of the legs of the box spring with the edge of the accordion box or on the plate which holds the box springs, which can be around the entire perimeter or in a punctual manner.  8) Device according to all of the preceding claims, characterized by a clamping pressure between the plates (1) and the base (4) which allows the vibrations of the blades (3)  CLAIMS. to propagate in the box spring (4) and the accordion case (6) and in the whole of the instrument.  9) Device according to claim 1) characterized in that the improvement of the seal between the plates (1) and the base (4) is ensured by 1 or 2 lips (10) or by a seal (11) in material flexible with closed cell which allows the contact of the plate (1) on the bed base (4).  10) Device according to claim 1) characterized by the presence of 7 or 2 lips between the valves (12) and the plate on which they are supported.  11) Device to improve the sound of guitars, violins, string double basses, clarinets, flutes, drums pianos characterized in that it is made of materials with a minimum hardness of 70 shores D.