JP4783177B2 - Black key of keyboard instrument - Google Patents

Description

  The present invention relates to a black key of a keyboard instrument such as a piano, and more particularly to a black key having a weight for adjusting a touch weight.

  For example, a black key of a grand piano generally includes a wooden key body extending in the front-rear direction, a black key cover attached to the key body, a weight attached to the key body, and the like. The key body is swingably supported by the balance pin at the center thereof, and an action is placed behind the balance pin of the key body. The black key cover is formed of a synthetic resin molded product such as phenol, is formed in a hollow shape with an open lower surface, and is bonded to the front portion of the upper surface of the key body.

  In the case of a grand piano, the weight is attached to the front side of the balance pin of the key body in order to give the black key a weight against the weight of the action and to obtain the required touch weight (static load). . Conventionally, the weight is generally made of cylindrical lead, and is attached to the key body by being inserted into a buried hole formed in the key body and caulked. Lead is used as a weight material because lead has a high specific gravity and is inexpensive, has high flexibility and ductility, and is suitable for mounting by caulking.

  However, since lead is a harmful substance, it is desirable not to use it as much as possible. Also, when the weight is attached by caulking as described above, the side of the weight is cut or a buried hole is newly formed in the key body when it is necessary to adjust the touch weight after the attachment. However, since it is unavoidable to add a weight or the like, it takes much time to adjust the touch weight.

  As a conventional black key for solving such a problem, for example, one disclosed in Patent Document 1 is known. In this black key, a block-like weight is accommodated in the hollow portion of the black key cover so as not to rotate and to be movable in the front-rear direction. The weight is made of a metal having a large specific gravity other than lead, for example, tungsten, iron, or a composite material of these metals and a synthetic resin. A screw hole penetrating in the front-rear direction is formed in the weight, and an adjustment screw is screwed into the screw hole and protrudes on both front and rear sides of the weight. The front end of the adjusting screw engages with the inner surface of the front wall of the black key cover, and the rear end engages with a hole formed in the back wall of the black key cover so as to be rotatable. A minus groove for rotating operation is formed.

  In this configuration, when the adjustment screw is rotated from the outside via the minus groove, the adjustment screw does not move, and the weight moves in the front-rear direction. Therefore, the touch weight is steplessly accurately determined according to the movement position. Can be adjusted. However, this conventional black key has a size and shape that can be accommodated in the black key cover, and it is necessary to specially make a block-like weight in which a screw hole is formed in advance, which increases the manufacturing cost. There is a problem.

  The present invention has been made to solve such a problem, and provides a black key of a keyboard instrument that can easily and inexpensively obtain a required touch weight without using lead or special parts. The purpose is to do.

JP 2001-215949 A

In order to achieve this object, the black key of the keyboard instrument of the present invention includes a swingable key body extending in the front-rear direction, a hollow part, and a weight insertion hole that is formed at one end part in the front-rear direction and continues to the hollow part. A black key cover attached to the front part of the top surface of the key body, and a screw part on the outer peripheral surface, and inserted into the hollow part of the black key cover through a weight insertion hole, and the screw part is hollow. A weight that is detachably fixed to the black key cover by being screwed to the inner wall surface of the portion, and the hollow portion of the black key cover is provided on the weight insertion hole side, and the outer diameter of the screw portion of the weight A non-threaded portion where the threaded portion cannot be screwed and a non-threaded portion on the opposite side of the weight insertion hole, and a width smaller than the non-threaded portion. and, wherein the Rukoto to have a, screwed portion into which the threaded portion is screwed.

  In the black key of this keyboard instrument, the weight is a screw-like one having a screw part on the outer peripheral surface, and is inserted into the hollow part of the black key cover through a weight insertion hole formed in the black key cover, and the screw. The part is screwed onto the inner wall surface of the hollow part, thereby being detachably fixed to the black key cover. In this way, since the weight is attached to the black key cover by screwing from the outside, the weight can be easily attached, and unlike the conventional caulking, the weight is not required to be flexible or ductile. As a result, materials other than lead can be widely used. Further, since the weight is detachably fixed to the black key cover, the required touch weight can be obtained by appropriately replacing the weight.

Further, since the weight is formed in a screw shape, for example, a commercially available steel screw can be used as the weight, thereby reducing the manufacturing cost. Furthermore, since the weight is accommodated by utilizing the hollow portion that is normally formed in the black key cover, the black key cover can be produced at low cost without significant design changes, and the weight is arranged in a space-efficient manner. be able to.
Further, a large non-threaded portion where the weight screw portion is not screwed is provided on the weight insertion hole side of the hollow portion of the black key cover, and the substantial screwing length of the weight is shortened accordingly. Therefore, the weight can be screwed more easily, and the load of the weight attaching operation and the removing operation can be reduced.

  The invention according to claim 2 is the black key of the keyboard musical instrument according to claim 1, wherein the weight is composed of one of a plurality of types of weights having the same diameter and pitch of the threaded portions and different weights. It is characterized by.

  In this configuration, the weight is composed of one of a plurality of types of weights having different weights. Therefore, a required touch weight can be easily obtained by selecting the weight having the optimum weight from these plural kinds of weights and attaching the weight to the black key cover. In addition, since the diameters and pitches of the threaded parts of the multiple types of weights are the same as each other, after replacing the weights, they can be easily screwed in when replacing with other types of weights. It can be done easily.

  According to a third aspect of the present invention, in the black key of the keyboard instrument according to the first or second aspect, the weight is bonded to the inner wall surface of the hollow portion in order to assist in fixing the weight to the black key cover. It is characterized by.

  Since black keys are repeatedly struck during performance, use of keyboard instruments, especially when the underside of the hollow part is open, when the weight is fixed only by screwing into the hollow part of the black key cover As the music progresses, the weight may be loosened or the black key cover may fall off, which may hinder the performance. In this configuration, since the weight is bonded to the inner wall surface of the black key cover in order to assist in fixing the weight, it is possible to reliably prevent the weight from being loosened or dropped off. In this case, by using an adhesive having a relatively small adhesive force, the weight can be easily removed by the rotation operation, and the weight can be replaced without any trouble.

According to a fourth aspect of the present invention, in the black key of the keyboard instrument according to any one of the first to third aspects, the weight insertion hole is formed at the rear end of the black key cover.

  In this configuration, the weight insertion hole formed at the rear end of the black key cover and the rear end of the weight exposed to the black key cover are not visible to the player side and do not affect the appearance of the black key at all. Therefore, the appearance of the keyboard instrument can be maintained well.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a black key of a grand piano to which the present invention is applied. As shown in the figure, the black key 1 includes a key body 2 and a black key cover 3 attached to the front portion of the upper surface of the key body 2.

  The key body 2 is made of a wooden material that is relatively light weight, such as spruce, is tenacious, and elastic, has a rectangular cross section, and extends in the front-rear direction. An intermediate seat plate 4 is bonded to the center of the upper surface of the key body 2, and a balance pin hole 5 is formed so as to penetrate these in the vertical direction. The black key 1 is swingably supported by engaging the balance pin hole 5 with a standing balance pin (not shown).

  Further, a capstan screw 7 is attached via a capstan seat plate 6 behind the balance pin hole 5 on the upper surface of the key body 2, and an action (not shown) is attached to the capstan screw 7. Is placed. In the above configuration, when the front portion of the black key 1 is pressed (pressed), the black key 1 swings around the balance pin and the action is activated by being pushed up by the capstan screw 7. The touch weight of the black key 1 is determined by the balance of the moment around the balance pin due to the weight of the action and the black key 1.

  The black key cover 3 is integrally formed of a molded product of a synthetic resin such as black phenol or ABS. As shown in FIGS. 2 and 3, the black key cover 3 includes left and right side walls 3a, 3a, a front wall 3b, a back wall 3c, and an upper wall 3d, and these walls 3a-3d. And has a hollow portion 8 whose lower surface is opened.

  A circular weight insertion hole 9 is formed in the back wall 3c. The hollow portion 8 is continuous to the weight insertion hole 9 and has a non-threaded portion 8a having a predetermined width, and a predetermined width that is continuous to the front side of the non-screwed portion 8a and is smaller than the non-screwed portion 8a. It is comprised by the screwing part 8b which has.

  As shown in FIG. 3, a weight 10 is accommodated in the hollow portion 8 of the black key cover 3. The weight 10 is provided to give the black key 1 a weight that opposes the weight of the action and to obtain a required touch weight (static load). In this embodiment, the weight 10 is comprised, for example with the screw made from a commercially available steel, and has the cylindrical base part 10a and the screw part 10b which follows the base part 10a. A minus groove 10c for rotating operation is formed on the end surface of the base 10a. The outer diameters of the base portion 10a and the screw portion 10b are substantially equal to the diameter of the weight insertion hole 9, and are slightly smaller than the width of the non-screwing portion 8a of the hollow portion 8 and slightly larger than the width of the screwing portion 8b.

  As shown in FIG. 4, the weight 10 includes three types of weights 10 </ b> A to 10 </ b> C, and any one of them is selectively attached to the black key cover 3. The weights 10A to 10C are different only in the length of the screw portion 10b, and the material, the length and diameter of the base portion 10a, and the diameter and pitch of the screw portion 10b are all the same, and therefore have different predetermined weights. Have.

  The weight 10 having the above configuration is attached to the black key cover 3 as follows. That is, as shown in FIG. 2, first, the adhesive 11 is applied in a spot shape on the outer peripheral surface of the threaded portion 10 b of one selected weight 10. The adhesive 11 is made of an adhesive having a relatively small adhesive force, such as vinyl acetate. Next, the weight 10 is inserted into the hollow portion 8 of the black key cover 3 through the weight insertion hole 9. Due to the dimensional relationship between the outer diameter of the screw portion 10b and the width of the non-threaded portion 8a and the screwed portion 8b of the hollow portion 8, when the weight 10 is inserted, the screw portion 10b is It passes through 8a without resistance and comes into contact with the screwing portion 10b.

  Next, the screw portion 10b is screwed until the end surface on the base portion 10a side is substantially flush with the back wall 3c of the black key cover 3 by turning the weight 10 with a screwdriver (not shown) through the minus groove 10c. Screw into the inner surfaces of the side walls 3a, 3a of the joint 8b by tapping. Thereby, as shown in FIG. 3, the weight 10 is fixed to the black key cover 3 in a state in which the screw portion 10b is screwed to the inner surface of each side wall 3a of the screwing portion 8b and bonded with the adhesive 11. Is done. Thereafter, the black key cover 3 to which the weight 10 is attached is adhered to the upper surface of the key body 2, and the assembly of the black key 1 is completed.

  The adjustment of the touch weight of the black key 1 is performed as follows, for example. That is, the balance pin hole 5 of the assembled black key 1 is engaged with the balance pin, the black key 1 is set, and the touch weight of the black key 1 is measured with the action placed on the black key 1. . If the measured touch weight is different from the required value, the weight 10 can be replaced by inserting the weight with the black key cover 3 attached to the key body 2 after removing the black key 1 from the balance pin. The weight 10 is removed from the black key cover 3 by turning the weight 10 through the minus groove 10 c exposed in the hole 9. Then, another appropriate type of weight 10 is selected, screwed into the black key cover 3 and attached in the same manner as described above. Then, the touch weight is measured again, it is confirmed that the required touch weight is obtained, and the touch weight adjustment operation is terminated.

  As described above, according to the black key 1 of the present embodiment, the weight 10 constituted by a screw is attached to the hollow portion 8 of the black key cover 3 by screwing from the outside through the weight insertion hole 9. 10 can be easily attached. Further, unlike the case of conventional caulking, since the weight 10 is not required to have flexibility or ductility, a material other than lead can be widely used as the material of the weight 10.

  Moreover, since a commercially available screw is used as the weight 10 and it is not necessary to make a weight specially, the manufacturing cost can be reduced. Furthermore, since the weight 10 is accommodated by utilizing the hollow portion that is normally formed in the black key cover, the black key cover 3 can be manufactured at low cost without significant design changes, and the weight 10 can be made space efficient. Can be placed well.

  Further, since the weight 10 is composed of three kinds of weights 10A to 10C having different weights, one having an appropriate weight is selected from the weights 10A to 10C, and the black key cover 3 is selected. The required touch weight can be easily obtained by attaching and replacing as needed. Moreover, since the diameters and pitches of the thread portions 10b of the weights 10A to 10C are the same, when the weight 10 is attached, when the weight 10 is replaced with another type of weight 10, it can be easily screwed. Can be easily replaced.

  In addition to the weight 10 being screwed into the side wall 3a of the hollow portion 8, the weight 10 is bonded in an auxiliary manner, so that the weight 10 can be securely loosened or dropped due to repeated keystrokes. Can be prevented. Further, since the adhesive 11 having a small adhesive force is used as the adhesive 11 in this case, the weight 10 can be easily removed by the rotation operation, and the weight 10 can be replaced without any trouble.

  Further, a non-threaded portion 8a having a large width to which the threaded portion 10b of the weight 10 is not screwed is provided on the weight insertion hole 9 side of the hollow portion 8, and the substantial screwing length of the weight 10 is correspondingly provided. Since the weight 10 is shortened, the weight 10 can be screwed in more easily, and the load of the weight 10 can be reduced.

  Further, since the weight insertion hole 9 is formed in the back wall 3c of the black key cover 3, the weight insertion hole 9 and the rear end portion of the weight 10 exposed to the weight insertion hole 9 cannot be seen from the player side. The appearance of 1 is not affected at all. Therefore, the appearance of the grand piano can be maintained well.

  In addition, this invention can be implemented in various aspects, without being limited to the described embodiment. For example, in the embodiment, the weight 10 is composed of three types of weights 10A to 10C having different weights, but the number of types may be increased, and thereby the touch weight of the black key 1 can be adjusted more finely. it can. Further, the weight of the weight 10 may be varied depending on the sound range or the like, whereby the touch weight can be adjusted more finely according to the sound range or the like.

  In the embodiment, the length of the screw portion 10b is changed in order to obtain a plurality of types of weights 10 having different weights. However, the size of the weight 10 may be the same and the specific gravity may be changed. Furthermore, in the embodiment, a commercially available steel screw is used as the weight 10, but it goes without saying that a screw made of a material other than lead or a specially made screw other than a commercially available screw may be used.

  Further, instead of the embodiment, the adhesion of the weight 10 to the hollow portion 8 of the black key cover 3 is omitted, the non-threaded portion 8a of the hollow portion 8 is omitted, and the width of the hollow portion 8 is set constant. Doing so is also within the scope of the present invention. In addition, it is possible to appropriately change the detailed configuration within the scope of the gist of the present invention.

  Furthermore, although the embodiment is an example of a black key of a grand piano, the present invention is applicable to all keyboard instruments in which a black key cover has a hollow portion and a weight is attached, such as an upright piano or a black key of an electronic piano. It is possible to apply widely to the black key.

It is a perspective view which shows the black key of the grand piano to which this invention is applied. It is a disassembled perspective view before the black key cover of a black key is assembled. It is a bottom view of the assembled black key cover. It is a side view showing a plurality of kinds of weights.

Explanation of symbols

1 Black key 2 Key body 3 Black key cover 3a Side wall (inner wall surface of the hollow part)
3c Back wall (rear end of black key cover)
8 Hollow part 8a Non-screwing part 8b Screwing part 9 Weight insertion hole 10 Weight 10b Screw part 11 Adhesive

Claims (4)

A swingable key body extending in the front-rear direction;
A black key cover that is formed in the hollow portion and at one end portion in the front-rear direction, has a weight insertion hole that is continuous with the hollow portion, and is attached to the front portion of the upper surface of the key body;
The black key cover has a threaded portion, is inserted into the hollow portion of the black key cover through the weight insertion hole, and the threaded portion is screwed into the inner wall surface of the hollow portion. removably and a weight which is fixed,
The hollow portion of the black key cover is
A non-threaded portion that is provided on the weight insertion hole side, has a width larger than the outer diameter of the threaded portion of the weight, and the threaded portion cannot be threaded;
The provided so as to be continuous to the non-threaded portion on the opposite side of the weight insertion hole, said has a smaller width than the non-screwed portion, that having a, screwed portion into which the threaded portion is screwed A black key for keyboard instruments.   2. The black key of a keyboard instrument according to claim 1, wherein the weight is formed of one of a plurality of types of weights having the same diameter and pitch of the threaded portions and different weights. .   3. The black key of a keyboard instrument according to claim 1, wherein the weight is bonded to the inner wall surface of the hollow portion in order to assist in fixing the weight to the black key cover. . The black key of a keyboard instrument according to any one of claims 1 to 3, wherein the weight insertion hole is formed in a rear end portion of the black key cover .

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