JP3604052B2 - Instrument keyboard - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a keyboard of a musical instrument, and more particularly to an improvement of a bushing cloth attached to a pin hole of a keyboard main body in an acoustic piano or the like.
[0002]
[Prior art]
Generally, in an acoustic piano such as a grand piano or an upright piano, the keyboard is supported swingably around a balance pin passing through a balance pin hole at a central portion of the keyboard, and is passed through a front pin hole at a front end of the keyboard. The front pin prevents the keyboard from swinging left and right. A bushing cloth is adhered to the inner surface of each of the balance pin hole and the front pin hole. Conventionally, this bushing cloth is made of a knitted soft wool fiber. The flexibility and lubricity of the bushing cloth compensate for variations in the dimensions of both pin holes, making the keyboard swing smoothly and eliminating noise when swinging. ing.
[0003]
[Problems to be solved by the invention]
The wool fiber used in the conventional bushing cloth has a relatively high abrasion resistance by nature, so that it can be applied without any problem when the piano is used for a short period of time. However, if the piano is used for a long period of time, the wear will gradually progress and the lubricity will decrease, causing the keyboard to rattle, making the touch feeling worse, and generating unpleasant noise Or you may. As a result, the bushing cloth needs to be replaced, and in the worst case, it also affects the life of the piano.
[0004]
The present invention has been made in order to solve such problems, and improves the lubricity and abrasion resistance of a bushing cloth, and can maintain the bushing cloth for a long period of time, thereby improving the durability of a musical instrument. It is intended to provide a keyboard.
[0005]
[Means for Solving the Problems]
In order to achieve this object, the keyboard of the musical instrument of the present invention has a pin hole, a wooden keyboard body swingably supported by a pin engaged with the pin hole, and a wool fiber, A bushing cloth adhered to the inner surface of the hole, wherein each wool fiber constituting the bushing cloth is coated with a fluorine resin.
[0006]
In the keyboard of this musical instrument, the wool fiber that constitutes the bushing cloth is coated with a fluoroplastic that is excellent in lubricity and abrasion resistance, so that the lubrication of the bushing cloth is improved and its function is improved, Wear is also reduced and its durability is improved. In addition, since the wool fiber is coated with a fluororesin one by one over the entire surface of the bushing cloth, even if the surface is worn, the lubricity is not reduced, and for a long time, Well maintained.
[0007]
In this case, it is preferable that each of the wool fibers is coated by impregnating a bushing cloth with a solution of a fluorine resin. According to this configuration, by impregnating the bushing cloth with the fluorine resin solution, the coating of each wool fiber can be performed easily and with less variation.
[0008]
In these cases, it is preferable that the fluorine resin is composed of a fluoropolymer. The fluorine-based polymer has excellent lubricity and abrasion resistance and high stability, especially among fluororesins, so that the function and durability of the bushing cloth can be further enhanced.
[0009]
Further, in these cases, it is preferable that the bushing cloth is bonded to the keyboard body with a thermoplastic resin adhesive. Fluoro resin inherently does not have good adhesive properties and acts to repel the adhesive.However, using a thermoplastic resin adhesive such as polyamide and curing it in a short time, the keyboard body made of wood material Due to the mechanical engagement (anchor effect) between the unevenness of the surface of the bushing and the unevenness of the surface of the bushing cloth made of wool fiber, even if the bushing cloth is coated with fluoro resin, the adhesive strength with the keyboard body is sufficient. Can be secured.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 3 shows a keyboard device including a keyboard (white key) of an upright piano to which the present invention is applied. As shown in FIG. 1, the keyboard 1 includes a keyboard body 2, a pair of bushing cloths 4, 4 bonded to a balance pin hole (pin hole) 3 at the center of the keyboard body 2, and a first half of the keyboard body 2. It is composed of an acrylic keyboard skin 5 adhered to the part.
[0011]
The keyboard body 2 is made of a relatively lightweight and highly elastic wooden material such as spruce and pine. On the upper surface of the central portion of the keyboard body 2, a middle seat plate 6 made of a harder wooden material is bonded for reinforcement. As shown in FIGS. 1 and 2, the balance pin hole 3 extends from the keyboard main body 2 to the middle seat plate 6, and is formed so as to penetrate them vertically, and a round hole at the lower end of the keyboard main body 2. It is composed of a portion 3a and an elongated guide hole 3b extending in the front-rear direction and connected to the upper side thereof.
[0012]
The bushing cloth 4 is composed of a rectangular wool cloth coated with a fluoro resin, and is manufactured, for example, as follows.
(1) First, as a material of the bushing cloth 4, a cloth raw cloth woven of wool fiber is prepared as in the conventional case.
(2) Next, the cloth cloth is impregnated with a fluororesin aqueous solution to be saturated. The aqueous fluororesin solution contains, for example, 4 to 5% by weight of a fluororesin, for example, a perfluoro-acryl-alkylate copolymer, and also contains a urethane-based binder and an emulsifier. By this impregnation, not only the surface of the raw cloth but also each of the wool fibers is coated with the fluororesin.
(3) Next, the cloth material is taken out from the fluororesin aqueous solution, dried at a predetermined temperature and time (eg, 100 ° C., 5 minutes), and further heated at a predetermined temperature and time (eg, 160 ° C., 30 seconds). In this way, curing is performed while promoting curing with the binder.
(4) Finally, the cloth cloth is cut into a rectangular shape having a predetermined size, and the manufacture of the bushing cloth 4 is completed.
[0013]
As shown in FIG. 2, the manufactured bushing cloth 4 is bent in an L-shape along the upper surface of the intermediate seat plate 6 from each inner surface of the guide long hole portion 3b of the balance pin hole 3, and is cured in a short time. It is bonded with a thermoplastic resin adhesive such as polyamide. Although not shown, the bushing cloth 4 is similarly attached to a front pin hole (pin hole) (not shown) formed to be opened on the lower surface of the front part of the keyboard main body 2.
[0014]
As shown in FIG. 3, the keyboard 1 having the above configuration has its balance pin hole 3 provided on a balance pin (pin) 8 provided upright in a reed 7 and the front pin hole provided upright on a front 9 of the reed. By engaging with front pins (pins) 10, respectively, it is attached to a reed 11 to which the reed 7 and the front 9 are fixed. As a result, the keyboard 1 is swingably supported about the balance pin 8, and the front pin 10 prevents left and right swing. Further, as shown in FIG. 2, the bushing cloth 4 makes light contact with the balance pin 8 and the front pin 10 from both sides, and the flexibility and smoothness of the bushing cloth 4 reduce the variation in the dimensions of the balance pin hole 3 and the front pin hole. By compensating, the function of smoothing the swing of the keyboard 2 and preventing noise at the time of the swing is achieved.
[0015]
In this case, as described above, the bushing cloth 4 of the present embodiment is coated with the perfluoro-acryl-alkylate copolymer having particularly excellent lubricity and abrasion resistance and high stability. As compared with the conventional bushing cloth, the above-mentioned function of the bushing cloth 4 is improved by improving the lubricity, and the durability can be improved by reducing the wear. In addition, since the fluororesin is coated not only on the surface of the bushing cloth 4 but also on each of the wool fibers by the impregnation with the fluororesin aqueous solution, even if the surface of the bushing cloth 4 is worn, the lubricity is reduced. Is maintained satisfactorily for a long time without lowering. As a result, even when the piano is used for a long period of time, the backlash of the keyboard 1, the feeling of touch, and unpleasant noise are very unlikely to occur, and the durability of the keyboard 1 is improved, and the life of the piano is extended. Can be.
[0016]
In addition, as the coating agent for the bushing cloth 4, another suitable fluororesin may be employed in place of the above-mentioned per-fluoro-acryl-alkylate copolymer . Fluoro resin generally has high lubricity and abrasion resistance, so that basically the same effects as described above can be obtained. In addition, although fluororesin inherently has poor adhesiveness and acts to repel the adhesive, as described above, by using a thermoplastic resin adhesive such as polyamide and curing it in a short time, wood The bushing cloth 4 is made of a fluororesin by mechanical engagement (anchor effect) between the unevenness of the surface of the keyboard body 2 and the middle seat plate 6 made of a material and the unevenness of the surface of the bushing cloth 4 made of wool fiber. , The adhesive strength between the keyboard body 2 and the middle seat plate 6 can be sufficiently ensured.
[0017]
Further, in the embodiment, the coating of the bushing cloth 4 is performed by impregnation with an aqueous solution of a fluororesin, but this can be performed by another appropriate method such as spraying. In particular, in the case of impregnation, there is an advantage that coating of each wool fiber can be performed easily and with less variation. Further, although the embodiment is an example of a keyboard of an upright piano, it is of course possible to apply the present invention to a keyboard of a grand piano or another suitable type of piano, such as an electronic piano or an organ. The same effect can be obtained even when used for a receiving member for other sliding parts and swinging parts in a piano or the like, for example, an action flange bushing cloth, a wippen heel cloth, or a damper lever punching cloth. Can be significantly increased. In addition, the configuration of the details can be appropriately changed within the scope of the present invention.
[0018]
【The invention's effect】
As described above, the keyboard of the musical instrument of the present invention has the effects of improving the lubricity and abrasion resistance of the bushing cloth and maintaining it for a long period of time, thereby improving the durability.
[Brief description of the drawings]
FIG. 1 is a partially enlarged side view showing a main part of a keyboard of an upright piano to which the present invention is applied.
FIG. 2 is a cross-sectional view of the keyboard of FIG.
FIG. 3 is a perspective view showing a keyboard device including the keyboard of FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Keyboard 2 Keyboard body 3 Balance pin hole 4 Bushing cross 8 Balance pin 10 Front pin

Claims (4)

A wooden keyboard main body having a pin hole and swingably supported by a pin engaged with the pin hole,
A bushing cloth made of wool fiber and adhered to the inner surface of the pin hole;
A keyboard for musical instruments, wherein each of the wool fibers constituting the bushing cloth is coated with a fluoro resin. The musical instrument keyboard according to claim 1, wherein each of the wool fibers is coated by impregnating the bushing cloth with a solution of the fluoro resin. 3. The keyboard of a musical instrument according to claim 1, wherein the fluorine resin is made of a fluoropolymer. 4. The keyboard of a musical instrument according to claim 1, wherein said bushing cloth is bonded to said keyboard body with a thermoplastic resin adhesive.

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