Abstract:
An adapter piece ( 28 ) for fixing a shoulder rest ( 30 ) on a string instrument, having an adapter body ( 38 ) provided with at least four clamping fingers ( 32 ) engageable with a peripheral bottom edge ( 12 ) of the string instrument to be supported, shall keep the tonal impairment of the instrument particularly low, offering, at the same time, a high stability. For this purpose, at least two of the clamping fingers ( 32 ) are positioned such that they are engageable with the peripheral bottom edge ( 12 ) in the area of the outer blocks ( 20 ) of the string instrument.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a national stage application under 35 U.S.C. 371 of PCT Application No. PCT/EP2008/006450 having an international filing date of 06 Aug. 2008, which designated the United States, which PCT application claimed the benefit of German Application No. 102007038004.8 filed 10 Aug. 2007, the entire disclosure of each of which are hereby incorporated herein by reference. 
     The invention related to an adapter piece for fixing a shoulder rest on a string instrument, having an adapter body provided with at least four clamping fingers engageable with a peripheral bottom edge of the string instrument to be supported. 
     BACKGROUND  
     String instruments, in particular violins and violas, are held, while being played, on their resonance-box end between the musician&#39;s chin and shoulder. As this causes, in the long run, for the musician a very uncomfortable position of the instrument, so-called chin rests and shoulder rests for violins and violas were developed. 
     These shoulder rests are detachably fixed, by means of a holding device, at the resonance box of the instrument and thus serve for making the holding of the instrument more comfortable for the musician. In general, a shoulder rest is fastened on a violin or the like, forming a support surface resting on the musician&#39;s shoulder, the instrument itself being supported on a selected level which depends on the musician&#39;s stature, in particular on the length of his or her neck. 
     Although numerous shoulder rests have been proposed and are available on the market, the types with a firm bottom, shaped according to the musician&#39;s shoulder, are preferred by a considerable part of the market. The underside of the firm bottom is usually provided with a pad resting against the musician&#39;s shoulder when the instrument is played. On the two ends of the bottom, holding elements or carrying elements rising upwards are mounted, which carry pivotable, forked end pieces. The latters can be fixed on the side walls of the resonance box of the instrument near the resonance-box bottom. To firmly fix this type of shoulder rest on the instrument, the bottom of the shoulder rest possesses a certain intrinisic elasticity serving for generating a certain clamping force with which the forked end pieces grasp the instrument. End pieces are also known in other embodiments in combination with the carrier elements, almost all of them, however, grasping the instrument with a certain clamping force. 
     To achieve a better adaption of the height level to the musician&#39;s neck, adapter pieces for shoulder rests have been developed. On the one hand, the shoulder rest is fixed to these adapter pieces, and on the other hand, the adapter piece is fastened to the instrument. Thus, the height of the instrument can be adapted by means of the adapter, to which shoulder rests of a simpler design, such as, for example, those with a simple flexible shoulder strap as shoulder support, can also be fixed. 
     These adapter pieces are often made of plastics or else of a lightweight metal, in order not to add too much weight. Such adapter pieces are in most cases fixed on the instrument, like the above-mentioned shoulder rests, by means of holding elements with end pieces, making use of certain clamping forces, near the bottom at the side of the resonance box of the instrument or at an angle over the edge of the resonance-box bottom. In most cases, such adapter pieces are braced in transverse direction relative to the longitudinal axis of the instrument at the widest spot of the resonance box or slightly diagonally to that spot. 
     The warpings which the adapter piece causes on the instrument are detrimental in this case because they result in a considerable impairment of the tonal quality. This is also valid for the so-called shoulder rests fixed through clamping forces. Furthermore, such a fixing of the adapter piece is not very stable, and when played in a very virtuoso way, the instrument tends to tilt or becomes partly detached from the holding elements. Adapter pieces from which the instrument will not be detached so easily are fixed under the resonance-box bottom almost over the entire surface, and their outer areas project over the resonance box of the instrument. This, however, hinders the musician in playing the instrument and, in addition, an adapter piece covering the entire surface considerably impairs the tonal quality of the instrument. 
     SUMMARY 
     Therefore, the invention is based on the task to provide an adapter piece of the above-mentioned type which offers a high stability and at the same time keeps the tonal impairment of the instrument particularly low. 
     This task is solved according to the invention by positioning at least two of the clamping fingers such that they are engageable with the peripheral bottom edge in the area of the outer blocks of the string instrument. 
     The invention is based on the idea that the tonal impairment of a string instrument can be kept low by adapting the mechanical contact of the adapter piece with the resonance box of the instrument specifically to the vibration behavior, because the impairment of the tonal purity and, therefore, the tonal quality of a string instrument results in particular from possible interventions into the vibration behavior. For taking the vibration behavior into account, one makes specific use of the knowledge that the resonance box of a string instrument possesses some spots where stiffeners of the resonance box are incorporated, so that there, vibration nodes tend to occur more frequently. At these stiffeners, the so-called blocks, the resonance box is, therefore, relatively vibration-insensitive to mechanical interventions and external contacts. Therefore, the adapter piece is designed for making the mechanical contact with the resonance box in these areas. 
     Advantageous embodiments of the invention are the subject matter of the dependent claims. 
     The positioning of the clamping fingers can be adapted to ergonomic or individual requirements. To achieve a particularly high stability of the adapter piece on the resonance box of the instrument, however, advantageously, two of the clamping fingers are positioned such that they are engageable with the peripheral bottom edge adjacent to the lower end block and on both sides thereof Through this symmetrical fixing, the vibration profile of the instrument is to a great extent taken into account. 
     Expediently, the adapter piece has an approximately horseshoe-shaped basic shape, the clamping fingers provided for the area of the outer blocks being fixed on the respective front end of the adapter body. Due to this horseshoe-shaped basic shape, the adapter body can be adapted, on the one hand, to the outer profile of the string instrument, and, on the other hand, only little material is required and, consequently, the weight is lower than in case of a design covering the entire surface. Furthermore, a good covering range and, therefore, a great stability are given, but unsightly projections as well as a certain bulkiness of the adapter body are also avoided. 
     Advantageously, the shape of the outer profiles of the adapter body is adapted to those of the instrument to be supported, in order to further use already existing shoulder rests without problems. Furthermore, the thickness of the adapter body is expediently approximately the same as the thickness of the peripheral bottom edge of the string instrument. Thus, conventional shoulder rests fit onto the adapter piece without problems and their holding elements can easily be fixed on the adapter body. Furthermore, an adapter body shaped in this way offers the advantage to avoid the above-mentioned unsightly projections and the bulkiness. 
     To offer the musician more freedom of movement and more comfort, the outer profile of the adapter body is advantageously provided, in the area corresponding to the lower end block of the string instrument to be supported, with a recess. This recess in the profile forms a clearance for the musician&#39;s clavicle. Thus, the adapter piece will not painfully press against the clavicle and will give the necessary freedom of movement which especially a solo performer requires when playing the instrument in a virtuoso way. 
     As string instruments are as a rule made of a special selected wood, which offers particularly good vibration and tonal properties, it is expedient to make the adapter piece from the same material. As the adapter piece covibrates when the string instrument is played, a particularly harmonic vibration behavior will be given in case of identical materials of adapter piece and resonance box. Usually, maple wood is used for the resonance box, which is also particularly suitable for manufacturing the adapter piece. The grain of the wood for the adapter piece should run in longitudinal direction of the instrument, to achieve a good bending behavior and also a good vibration behavior. Plastics suitable for instrument making, from which the adapter piece can be made, are also imaginable. 
     To avoid inadvertent damage, such as, for example, scratches in the varnish and/or even in the wood, when fixing the adapter piece on the resonance box of the instrument or removing it therefrom, it will be an advantage if the clamping fingers are provided on their inside with a protective lining. Preferably, this protective lining is designed as a felt lining, resulting in that felt guarantees very agreeable attenuation properties, so that the tonal quality of the string instrument is preserved. Other protective linings of the clamping fingers, such as, for example, foamed materials, textile fabrics or the like, can be used instead of felt. 
     It is expedient, in particular in view of fixing the clamping fingers on the resonance box and the resulting vibration behavior with regard to the tonal quality of the string instrument, to design the clamping fingers, at least those positioned in the area of the outer blocks, in such a way that their clamping hooks only grasp around the peripheral bottom edge, without touching the bottom or the wall of the resonance box. At these spots in the area of the outer blocks, a mechanical intervention has the least effects on the vibration behavior and guarantees a good tonal purity of the string instrument. 
     To be able to fix a plurality of different shoulder rests on the adapter piece, it is an advantage to provide means for fastening a shoulder rest on the adapter body. Such means can in the simplest way be holes for receiving setscrews, but also sleeves with locking screws integrally formed and/or attached onto the adapter body, to fix small spacing bars. Conventional shoulder rests with clamping devices can in this case easily be clamped onto the adapter body. 
     To adapt the height of the shoulder rest to the anatomy of the musician&#39;s neck, expediently a number of rotary wheels with setscrews arranged on both sides and provided each with contradirectional thread leads are fixed on the adapter piece, the setscrews engaging, on the one hand, into an associated threaded hole and/or thread in the adapter body and, on the other hand, into an associated thread in the shoulder rest. To mount the shoulder rest, the rotary wheel is rotated, and due to the contradirectional thread leads, the setscrews are tightened in both threaded holes. This brings about a very simple and firm, stable fastening and, at the same time, within certain limits, a height regulation of the shoulder rest. 
     The respective rotary wheel has expediently a diameter of minimally 15 mm to maximally 40 mm, to enable a sufficiently large contact surface of adapter piece and shoulder rest. A usual diameter can be in the range of 15 mm to 25 mm, to offer, on the one hand, sufficient clearance and to achieve, on the other hand, a good handlability of the rotary wheel. Thus, a bracing over the entire surface can be given, guaranteeing a good stability between shoulder rest and adapter piece. 
     The use of the adapter piece is particularly advantageous on string instruments, in particular on violins and violas, as the resonance box of these instruments is held between the musician&#39;s head and shoulder. However, a use on violoncellos is also imaginable, with the exception that in that case, instead of the shoulder rest, the spike for putting up the violoncello is fixed on the adapter piece. 
     The advantages achieved with the invention consist in particular in that an adapter piece for fixing a shoulder rest for string instruments with clamping fingers fixed in the area of the outer blocks of the resonance box of the instrument on the peripheral bottom edge, do not greatly influence the vibration behavior of the instrument, so that its high tonal quality is preserved. Furthermore, the shape of the adapter piece is adapted to the resonance box of the instrument and is easy to assembly and disassemble. In addition, the adapter piece guarantees a secure and comfortable holding of the string instrument and, at the same time, a high freedom of movement of the musician. Furthermore, a plurality of different shoulder rests, even already existing shoulder rests with clamping-element fixtures, can be fastened to the adapter piece. 
    
    
     
       DESCRIPTION OF THE FIGURES 
       An exemplary embodiment of the invention is explained in detail by means of a drawing in which 
         FIG. 1  is a bottom view of a classical violin with indication of the position of the blocks, 
         FIG. 2  is a perspective partial view of a violin with attached adapter piece and shoulder piece, 
         FIG. 3  is an enlarged detail of an area of an outer block with attached clamping finger from  FIG. 2 , 
         FIG. 4  is a perspective view of the adapter piece with shoulder rest from  FIG. 2 , and 
         FIG. 5  is a partial view of an adapter body with screwed-on shoulder rest. 
       Identical parts are marked with identical reference numbers in all figures. 
     
    
    
     DETAILED DESCRIPTION   
     A classical violin  1  according to  FIG. 1  comprises a resonance box  2  forming the resonance body, a neck  4 , on which a fingerboard is fixed, and a pegbox with tuning pegs  6 , ending in a scroll  8 . The resonance box  2  includes a resonance-box bottom  10  as well as a peripheral bottom edge  12 . On the neck-side end  14  of the resonance box  2 , the neck  4  of the violin  1  is connected via the upper end block  16  with the resonance box  2 . Other blocks, serving for stabilizing the violin  1 , are incorporated in the resonance box  2  and, therefore, indicated here only in dotted lines, as these blocks are not visible from outside. These blocks comprise one lower end block  18  as well as, in most cases, four outer blocks  20 ,  22 , arranged on the ends of the area of a lateral inward curvature  24  of the resonance box  2 . 
     At the lower end block  18 , the strings of the violin  1  are tightened by means of a tailpiece end on the top side of the violin  1 . Therefore, the lower end block  18  is incorporated in the resonance box  2  in a very stable and firm manner. The upper end block  16 , carrying the neck  4  and the fingerboard, is also incorporated in the resonance box  2  in a stable and firm manner. The upper end block  16  and the neck  4  are today in most cases manufactured separately and glued together, to fulfill the required carrying properties as well as tonal and vibration properties. 
     On the sides of the resonance-box bottom  10 , in the area of the peripheral bottom edge  12 , side walls, so-called ribs  26 , are put up, and on these ribs  26 , opposite of the resonance-box bottom, a resonance-box cover is fastened. These parts essentially form the resonance box  2 , representing the resonance room of the violin  1 , and are stabilized by means of the outer blocks  20 ,  22  and the upper and lower end blocks  16 ,  18 . 
     In order not to impair the tonal quality of the violin  1  through external mechanical interventions, but to offer the musician, nevertheless, a comfortable holding of the violin  1 , an adapter piece  28 , on which a shoulder rest  30  is fixed, is fixed by means of four clamping fingers  32  in vibration-insensitive areas of the resonance box  2 .  FIG. 2  shows that the clamping hooks  34  of the clamping fingers  32  only grasp the peripheral bottom edge  12  in the area of the outer blocks  20  and of the lower end block  18 .  FIG. 3  shows an enlarged view of the grasp of one of the clamping fingers  32  with one of the felt-coated clamping hook  34 . One recognizes there that the felt-covered clamping hook  34  only grasps around the peripheral bottom edge  12 , without touching the resonance-box bottom  10  or the rib  26 . These areas of the outer block  20  as well as the area of the lower end block  18  tend to be vibration nodes more often and are, therefore, relatively insensitive to an external mechanical intervention. 
     The shoulder rest  30  fixed on the adapter piece  28  is a rest of conventional design, clamped onto the adapter body  38  with a separate clamping device  36 . This shoulder rest  30  could also be clamped onto the violin  1  directly, without the adapter piece  28 , but this would have the disadvantage that warpings of the resonance box  2  occur, impairing the tonal quality of the violin  1 . 
       FIG. 4  shows that the adapter piece  28  has a kind of horseshoe shape, adapted to the outer profile of the violin  1 . It is easy to recognize that there is a recess  40  in the area of the adapter body  38  corresponding to the lower end block  18 . This recess  40  offers sufficient clearance for the musician&#39;s clavicle. Furthermore, it will be recognized that the adapter body  38  has approximately the same thickness as the peripheral bottom edge  10 . 
       FIG. 2  shows clearly that the clamping fingers  32  with the clamping hooks  34  are variably adjustable in longitudinal direction, within certain limits. A kind of oblong eyelet  42  allows a certain adjustability of the clamping fingers  32 , as the screws  44 , with which the clamping fingers  32  are fixed on the adapter body  38 , are fixed in a releasable manner. Once the clamping fingers  32  have been adjusted in a way adapted to the resonance-box bottom  10 , or, in better words, to the peripheral bottom edge  12 , of the violin  1 , the screws  44  will be tightened again. Therefore, the clamping fingers  32  include inside a threaded adapter piece matching the screws  44 . It is also imaginable to manufacture the adapter piece  28  in a simpler embodiment with firmly attached clamping fingers  32 . 
     The arrangement of the clamping fingers  32  on the adapter body  38  is to a great extent symmetrical, so that two of the clamping fingers  32  are fixed on a front end  46  and the other two clamping fingers  32 , symmetrically immediately next to the recess  40 . Furthermore, the clamping hooks  34  are arranged such that in each case the grasping profiles of a clamping hook  34  on the front end  46  and of a clamping hook  34  next to the recess  40  are to a great extent opposite to each other. In this way, the violin  1  is protected against slipping in the adapter piece  28 , even when played in a very virtuoso way. 
       FIG. 5  shows that the shoulder rest  30  is screwed into the adapter body  38  by means of setscrews  48  and rotary wheels  50  with contradirectional internal thread leads. For this purpose, two threaded holes  52  are drilled into the adapter body  38 . Alternatively to the threaded holes  52 , threaded bushes can be fixed on the adapter body  38 . The rotary wheels  50  serve for easy assembly and disassembly of the shoulder rest  30  on the adapter piece  28  and enable, by means of the setscrews  48 , a certain height-level adjustment of the shoulder rest  30 . Furthermore, the rotary wheels  50  with their diameter of 15 mm to 25 mm offer a sufficiently large contact surface and thus a good stability between adapter body  38  and shoulder rest  30 . 
     The adapter piece  28  for the violin  1  represented in  FIGS. 2 to 4  is just an exemplary embodiment. The adapter piece  28  can also be manufactured in a size suitable for violas as well as for violoncellos. In the latter case, a spike for putting up the instrument on the floor can be fixed instead of a shoulder rest  30 . Furthermore, the shoulder rest  30  shown here is just one example of many to be fixed on the adapter piece  28 . Furthermore, a chin rest can also be fixed on the adapter piece  28 , either by screwing it into holes provided for that purpose or by means of holding clamps provided on the chin rest. 
     List of Reference Numbers 
     
         
         
           
               1  Violin 
               2  Resonance box 
               4  Neck 
               6  Tuning peg 
               8  Scroll 
               10  Resonance-box bottom 
               12  Bottom edge 
               14  Neck-side end 
               16  Upper end block 
               18  Lower end block 
               20 ,  22  Outer block 
               24  Curvature 
               26  Rib 
               28  Adapter piece 
               30  Shoulder rest 
               32  Clamping finger 
               34  Clamping hook 
               36  Clamping device 
               38  Adapter body 
               40  Recess 
               42  Eyelet 
               44  Screw 
               46  Front end 
               48  Setscrew 
               50  Rotary wheel 
               52  Threaded hole