Keyboard weight of keyboard instrument, key attached to keyboard weight, and method of attaching keyboard weight

Abstract

A keyboard weight includes: a weight body made of a material other than lead and formed in a cylindrical shape having a predetermined diameter and a predetermined length; and a hollow member made of a material other than lead, formed in a cylindrical shape having an inner diameter allowing the weight body to be inserted into the hollow member, an outer diameter allowing the hollow member to be inserted into the insertion hole, and a predetermined length, and in a state in which the weight body is inserted inward when the keyboard weight is attached to the key, the hollow member is inserted into the insertion hole. And an insert inserted into the insert hole. The hollow member is provided with a thin portion extending along the entire circumferential direction, having a predetermined width in the length direction, and having a thickness smaller than that of other portions of the hollow member. The hollow member is configured such that when the keyboard weight is attached to the key, the hollow member is pressed from both sides in the length direction, thereby bending from the thin portion.

Description

Technical Field

[0001] This invention relates to keyboard devices for keyboard musical instruments (such as acoustic pianos), and to a keyboard weight attached to a key to obtain a desired touch weight when the key is pressed, a key attached to the keyboard weight, and a method of attaching the keyboard weight. Background Technology

[0002] Conventionally, in acoustic pianos (such as grand pianos), a weight is generally attached to the keys to provide the desired tactile weight when the keys are pressed. Lead is used as such a keyboard weight from the viewpoints of high density, low cost, and ease of processing. Insertion holes penetrating the keys in the left-right direction are provided at predetermined positions on the front portion of the keys extending in the front-back direction. With the keyboard weight inserted into the insertion holes, it is attached to the keys by pressing and stitching from the left and right sides using a stitching machine.

[0003] Since lead is a hazardous substance, it is ideal to avoid using it as a keyboard weight whenever possible. The applicant has proposed various keyboard weights made from alternative materials instead of lead, and, for example, those described in JP2003-122344 A are known.

[0004] The keyboard weight described in JP 2003-122344 A includes a cylindrical weight and a cylindrical component into which the weight can be inserted. The weight is made of a relatively heavy material other than lead (e.g., iron, copper, brass, alloys, metals, and composites of synthetic resins). The cylindrical component, on the other hand, has a thin cylindrical shape with open ends and an outer diameter slightly smaller than the diameter of the insertion hole formed in the key. Furthermore, the cylindrical component is made of a relatively easily deformable material other than lead (e.g., metals such as aluminum, plastics, or elastic materials such as rubber). Additionally, the cylindrical component is provided with a slit extending along its entire length.

[0005] In the case where a keyboard weight, constructed as described above, is attached to a key's insertion hole, firstly, a cylindrical component is inserted into the insertion hole. Next, with the distal end of the weight inserted into the cylindrical component, the weight is driven by a hammer or similar device and press-fitted into the cylindrical component. Therefore, the cylindrical component is pushed outwards radially and expanded by the press-fitted weight, and presses against the wall surface of the insertion hole. As a result, the weight is securely fixed to the key via the cylindrical component.

[0006] Citation List Patent documents Patent document 1: JP 2003-122344 A. Summary of the Invention

[0007] In the conventional keyboard weight attachment scenario described above, where the distal end of the weight is inserted into a cylindrical component inserted into the key's mounting hole, the weight is driven by a hammer, causing the entire outer circumferential surface of the cylindrical component to expand radially outward. In this case, when the weight is immediately driven with a relatively large force, cracks may appear around the key's mounting hole due to the rapid outward expansion along the radial direction of the cylindrical component. Alternatively, driving the weight gradually with a relatively small force can suppress the occurrence of the cracks described above, but this takes time to attach the weight to the key, and reduces the key's manufacturing efficiency.

[0008] The present invention has been made to solve the problems described above, and its objective is to provide a keyboard weight that can be easily manufactured using alternative materials instead of lead and can be easily attached to the keys, the keys attached to the keyboard weight, and a method for attaching the keyboard weight.

[0009] To achieve the above objective, according to the invention based on the first aspect, a keyboard weight is provided, which, in an inserted state, is immovably attached to a through-hole with a predetermined diameter formed in the keys of a keyboard instrument. The keyboard weight includes: a weight body made of a material other than lead and formed into a cylindrical shape having a predetermined diameter and a predetermined length; and a hollow member made of a material other than lead and formed into a cylindrical shape having an inner diameter allowing the weight body to be inserted into the hollow member, an outer diameter allowing the hollow member to be inserted into the through-hole, and a predetermined length longer than the weight body, and wherein, when the keyboard weight is attached to the keys and the weight body is inserted inward, it is inserted into the through-hole. The hollow member is provided with a thin portion extending along the entire circumferential direction, having a predetermined width along the length direction, and having a predetermined thickness smaller than the thickness of other parts of the hollow member. The hollow member is configured such that when the keyboard weight is attached to the keys, the hollow member is pressed from both sides along the length direction, thereby buckling starting from the thin portion.

[0010] According to this construction, the keyboard weight attached to the key's insertion hole includes: a cylindrical weight body made of a material other than lead; and a cylindrical hollow component. The hollow component has a thin portion extending along the entire circumferential direction, having a predetermined width along the length direction, and a predetermined thickness smaller than the thickness of other portions. When the keyboard weight is attached in the state of being inserted into the key's insertion hole, the hollow component is pressed from both sides along the length direction, thereby causing buckling starting from the thin portion within the hollow component. As a result, the peripheral portion of the hollow component, including the thin portion (hereinafter referred to in the art as the "deformed portion"), deforms inward and outward along the radial direction of the hollow component. Therefore, the deformed portion deformed outward along the radial direction bites into or is forcefully pressed into the wall surface of the key's insertion hole, while the deformed portion deformed inward along the radial direction bites into or is forcefully pressed into the outer peripheral surface of the weight body. As a result, the keyboard weight is securely attached to the key's insertion hole.

[0011] Since the main body of the keyboard weight is cylindrical, it can be easily obtained, for example, by cutting a long cylindrical bar with the same diameter as the main body to the same length as the main body. Furthermore, since the hollow component of the keyboard weight is cylindrical, it can be easily obtained, for example, by cutting a long cylindrical tube with the same external shape and thickness as the hollow component to the same length as the hollow component and placing thin portions in each long cylindrical tube. Moreover, as described above, when the keyboard weight is attached to a key, the keyboard weight inserted into the key's insertion hole can be pressed from both sides along its length, allowing the keyboard weight to be attached using a conventional stitching machine. As described above, according to the present invention, a keyboard weight can be obtained that is easy to manufacture and easy to attach to a key, while using alternative materials instead of lead.

[0012] According to the invention of the second aspect, in the keyboard weight of the first aspect, the thin portion is formed by providing a groove located at the center of the hollow component along the length direction and opening outward in the radial direction.

[0013] According to this structure, a thin section can be easily formed by cutting or forming a groove that opens outward in the radial direction at the center of the outer peripheral surface of a cylindrical component that does not have a thin section along the length direction.

[0014] According to the invention of the third aspect, in the keyboard weight according to the second aspect, the two end portions of the hollow component into which the weight body is inserted are provided with locking portions, said locking portions being formed to protrude inward in the radial direction and lock the weight body immovably along the length direction of the hollow component.

[0015] According to this construction, the main body of the weight is locked immovably along the length of the hollow component by locking portions located at both ends of the hollow component into which the main body of the weight is inserted. Therefore, when the keyboard weight is pressed and attached from both sides along the length of the hollow component while it is inserted into the key's mounting hole, the main body of the weight can be stably attached without shifting along the length of the hollow component.

[0016] According to the invention of the fourth aspect, a key is provided, comprising: a key body made of wood extending in a front-rear direction and configured to be oscillating, the key body having an insert hole at a predetermined position in the front-rear direction penetrating the key body in a left-right direction; and a keyboard weight attached by being pressed from both the left and right sides of the key body while inserted into the insert hole of the key body, wherein the keyboard weight includes the keyboard weight according to any one of the first to third aspects.

[0017] According to this construction, since the keyboard weight according to any one of the first to third aspects is attached to the key by being pressed from both the left and right sides of the key body while inserted into the embedding hole of the key body, it is possible to obtain a key to which the keyboard weight is attached has the functions and effects of the first to third aspects described above.

[0018] According to the invention in the fifth aspect, a method for attaching a keyboard weight is provided, comprising: a weight preparation step of preparing a weight body and a hollow component according to the first aspect; a key preparation step of preparing a key having an insertion hole according to the first aspect; a keyboard weight manufacturing step of manufacturing the keyboard weight by inserting the weight body into the hollow component; a keyboard weight insertion step of inserting the manufactured keyboard weight into the insertion hole of the key; and a keyboard weight attachment step of attaching the keyboard weight in a state of being fixed to the insertion hole of the key by pressing the keyboard weight from both sides along the length direction to cause bending starting from the thin portion.

[0019] According to this construction, firstly, a main body and a hollow component according to the first aspect, and a key with an insertion hole according to the first aspect are prepared (weight component preparation step and key preparation step). Next, the keyboard weight is manufactured by inserting the main body into the hollow component (keyboard weight manufacturing step), and the manufactured keyboard weight is inserted into the insertion hole of the key (keyboard weight insertion step). By pressing the keyboard weight from both sides along the length direction, bending is caused starting from the thin portion of the hollow component, thereby attaching the keyboard weight to the insertion hole of the key in a fixed state (keyboard weight attachment step). As described above, by causing bending starting from the thin portion of the hollow component, the deformed portion bites into the wall surface of the insertion hole of the key or is pressed forcefully, and bites into the outer peripheral surface of the main body of the weight or is pressed forcefully. As a result, the keyboard weight is firmly attached to the insertion hole of the key. As described above, according to the present invention, a keyboard weight made of an alternative material instead of lead can be easily and firmly attached to the insertion hole of the key.

[0020] According to the invention according to the sixth aspect, in the method according to the fifth aspect, in the keyboard weight manufacturing step, in the state where the weight body is inserted into the hollow component, the two end portions of the hollow component are pressed from both sides to deform so as to protrude inward in the radial direction, and to form a locking portion for locking the weight body immovably along the length direction of the hollow component.

[0021] According to this construction, in the keyboard weight manufacturing step, the locking portion is formed by pressing down on both ends of the hollow component while the weight body is inserted into the hollow component. As a result, a locking portion for locking the weight body inserted into the hollow component immovably along the length direction of the hollow component can be formed relatively easily. Furthermore, when the keyboard weight with the locking portion is pressed down and attached from both sides along the length direction of the hollow component while inserted into the key's insertion hole, the weight body can be stably attached without shifting along the length direction of the hollow component. Attached Figure Description

[0022] Figures 1A to 1C This is a view used to illustrate a keyboard weight according to a first embodiment of the present invention, wherein, Figure 1A This is a perspective view of the keyboard weight shown in the image. Figure 1B It is a cross-sectional view of a keyboard weight cut along its length, and... Figure 1C This is a perspective view showing the main body and hollow components of the keyboard weight in a separated state. Figure 2 It is a diagram. Figure 1A A perspective view of the keys to which the keyboard weight is attached; Figure 3It is a view used to illustrate the method of attaching a keyboard weight to the keys, and is an illustrative view of the steps for preparing the weight component and the steps for preparing the keys; Figure 4 yes Figure 3 The following view is an illustrative view of the keyboard weight manufacturing process; Figure 5A and Figure 5B yes Figure 4 The following views are illustrative views of the keyboard weight insertion and attachment steps, in which... Figure 5A It is a perspective view of the keyboard weight inserted into the recessed hole and its surroundings, and, Figure 5B It is a cross-sectional view of a keyboard weight cut along its length; Figure 6A and Figure 6B yes Figure 5A and Figure 5B The following view shows the state in which the keyboard weight is attached to the keys. Figure 6A It is a perspective view of the keyboard weight and its surroundings, and, Figure 6B It is a cross-sectional view of a keyboard weight cut along its length; Figure 7A and Figure 7B This is a view used to illustrate a keyboard weight according to a second embodiment of the present invention, wherein, Figure 7A It is a perspective view of the keyboard weight, and... Figure 7B It is a cross-sectional view of a keyboard weight cut along its length; Figure 8 It is used to explain the manufacturing process. Figure 7A The illustration shows an illustrative view of the method for using a keyboard weight according to the second embodiment. Figure 9 This is a view used to illustrate the method of attaching a keyboard weight according to the second embodiment, and is an illustrative view of the weight component preparation steps and the key preparation steps. Figure 10A and Figure 10B yes Figure 9 The following view is an illustrative view of the keyboard weight manufacturing process, in which... Figure 10A This is a perspective view illustrating the state in which the main body of the heavy object is inserted into the hollow component, and... Figure 10B This is a perspective view illustrating the state in which multiple locking parts are formed at the two end portions of the hollow component; Figure 11 yes Figure 10A and Figure 10B The following views are illustrative views of the keyboard weight insertion and attachment steps; and Figure 12yes Figure 11 The following view shows the state in which the keyboard weight is attached to the keys. Detailed Implementation

[0023] Preferred embodiments of the invention will be described in detail below with reference to the accompanying drawings. Figures 1A to 1C This is a view used to illustrate a keyboard weight according to a first embodiment of the present invention, wherein, Figure 1A This is an external perspective view of the keyboard weight. Figure 1B It is a cross-sectional view of the keyboard weight, and, Figure 1C This is a perspective view showing the main body and hollow component of the keyboard weight in a separated state. As illustrated in these figures, the keyboard weight 1 is a weight attached to the keys of a keyboard device (such as a grand piano) and is made of a material with a relatively high specific gravity other than lead (e.g., a metal such as copper or brass).

[0024] The keyboard weight 1 includes: a weight body 2 formed in a cylindrical shape with predetermined dimensions; and a hollow component 3 formed in a cylindrical shape with predetermined dimensions in which the weight body 2 can be accommodated.

[0025] Specifically, the main body 2 of the weight is formed into a cylindrical shape with a predetermined diameter (e.g., 12 mm) and a predetermined length (e.g., 10 mm).

[0026] On the other hand, the hollow component 3 has a predetermined outer diameter (e.g., 14 mm), a predetermined thickness (e.g., 0.8 mm), and a predetermined length (e.g., 14 mm), and is formed into a cylindrical shape that is slightly longer than the main body 2 of the weight. Furthermore, the hollow component 3 is provided with a thin portion 4, which extends throughout the circumferential direction and is thinner at its center along the length direction than other portions. Specifically, the thin portion 4 has a predetermined thickness (e.g., 0.2 mm) and a predetermined width (e.g., 0.5 to 1.0 mm). The thin portion 4 is formed by creating a groove 5 that opens radially outward relative to the metal cylindrical component before the thin portion 4 is provided, by cutting or the like.

[0027] Figure 2 The diagram shows the white key 10 attached to the keyboard weight 1. Figure 2 As shown in the figure, key 10 includes: key body 11 extending in a front-rear direction; white key cover 12 attached to the front portion of key body 11; and keyboard weight 1 attached to a predetermined position on the front portion of key body 11.

[0028] The key body 11 is made of a relatively light, tough, and flexible wood (such as spruce), has a rectangular cross-section, and extends in the front-to-back direction. A white key cover 12 is formed in an L-shape from plastic (such as acrylic) and is attached to the upper surface and the front half of the front surface of the key body 11 to cover them. A center plate 13 is attached to the central portion of the upper surface of the key body 11, and balance pin holes 14 are formed to penetrate them in the vertical direction. The key 10 is pivotally supported by the balance pin holes 14 that engage with an upright balance pin (not shown).

[0029] Furthermore, the winch screw 16 is attached to the upper surface of the key body 11 at a position after the balance pin hole 14, with the winch seat plate 15 in between, and the action mechanism (not shown) for transmitting the operation of the key 10 to the hammers for string striking is placed on the winch screw 16.

[0030] Furthermore, an insertion hole 11a penetrating the key body 11 in the left-right direction is formed at a predetermined position on the front part of the key body 11. The keyboard weight 1 is attached to the key body 11 by means of a closed-slit when inserted into the insertion hole 11a.

[0031] Next, we will refer to Figures 3 to 6B The method for attaching the keyboard weight 1 to the key 10 is described. First, as... Figure 3 As shown in the figure, prepare the main body 2 and hollow component 3 of the weight described above (weight component preparation step), and prepare the key 10 for attaching the keyboard weight 1 (key preparation step).

[0032] Specifically, the weight body 2 is manufactured by cutting a long cylindrical bar made of copper or brass with the same diameter (e.g., 12 mm) as the weight body 2 to the same length (e.g., 10 mm). On the other hand, the hollow component 3 is manufactured by cutting a long cylindrical tube made of copper or brass with the same outer diameter (e.g., 14 mm) and thickness (e.g., 0.8 mm) as the hollow component 3 to the same length (e.g., 14 mm), and forming a groove 5 (e.g., 0.6 mm deep and 0.5 to 1.0 mm wide) in each cylindrical tube. As for the key 10, an insertion hole 11a (e.g., 14 mm in diameter) penetrating the key body 11 in the left-right direction is formed at a predetermined position on the key body 11.

[0033] Next, as Figure 4As illustrated, the keyboard weight 1 is manufactured by inserting the weight body 2 into the hollow component 3 (keyboard weight manufacturing step). In this case, the weight body 2 is inserted into the hollow component 3 such that its center along the length direction matches the center of the hollow component 3. As a result, the entire weight body 2 is housed in the hollow component 3, and the two end portions of the hollow component 3 protrude slightly outward from the end surfaces of the weight body 2.

[0034] Next, as Figure 5A As illustrated in the diagram, the keyboard weight 1, manufactured as described above, is inserted into the insertion hole 11a of the key 10 (keyboard weight insertion step). In this case, the keyboard weight 1 is inserted into the insertion hole 11a such that the two end portions of the hollow component 3 protrude outward from the insertion hole 11a by the same length.

[0035] Then, as Figure 5B As illustrated, using a pre-defined sew-forming machine 20 with two pressing portions 21 and 21 facing each other, the keyboard weight 1 inserted into the insertion hole 11a is pressed from both the left and right sides of the key 10 by both pressing portions 21 and 21 (keyboard weight attachment step). Specifically, the two end portions of the hollow part 3 of the keyboard weight 1 are pressed from both sides. As the sew-forming machine 20 described above, a conventional sew-forming machine used when attaching the key to the insertion hole can be used.

[0036] Figure 6A and Figure 6B The diagram shows the state where the keyboard weight 1 is attached to key 10 by pressing it. (As described above...) Figure 5B In the keyboard weight 1 illustrated, when the two end portions of the hollow component 3 are pressed, the hollow component 3 buckles starting from the thinner portion 4, which is more easily deformed than the other parts of the hollow component 3. As a result, in the hollow component 3, such as Figure 6B As shown in the figure, the peripheral portion including the thin portion 4 deforms inward and outward in the radial direction.

[0037] Figure 6B The illustration shows an example of the deformed state of the peripheral portion (hereinafter referred to as "deformed portion 6") of the hollow component 3, including the thin portion 4. Figure 6B In this configuration, the deformable portion 6 deforms relatively outward in the radial direction to engage with the wall surface of the insertion hole 11a of the key body 11, and deforms slightly inward in the radial direction to engage slightly with the weight body 2 or forcefully press against the outer peripheral surface of the weight body 2. As a result, the keyboard weight 1 is firmly attached to the insertion hole 11a of the key body 11. When the keyboard weight 1 is attached to the key 10, the two end surfaces of the hollow component 3 are substantially flush with the left and right surfaces of the key body 11.

[0038] As described in detail above, according to this embodiment, the keyboard weight 1 can be easily manufactured and easily attached to the keys 10, while using alternative materials instead of lead. Furthermore, the keys 10 to which the keyboard weight 1 is securely attached can be obtained.

[0039] Next, we will refer to Figure 7A and Figure 7B The second embodiment of the keyboard weight according to the present invention is described below. In the following description, components similar to those of the keyboard weight 1 of the first embodiment described above are referred to by the same reference numerals, and their descriptions will be omitted.

[0040] The keyboard weight 1A in this embodiment differs from the keyboard weight 1 in the first embodiment described above only in that the main body 2 of the weight inserted inward is partially closed at both ends of the hollow component 3. That is, as Figure 7A and Figure 7B As illustrated in the diagram, in the keyboard weight 1A, multiple locking portions 3L and 3R for immovably locking the weight body 2 along the length direction of the hollow component 3 are provided at both end portions of the hollow component 3. Specifically, four locking portions 3L arranged at equal angles to each other along the circumferential direction of the hollow component 3 are provided at one end portion of the hollow component 3 of the keyboard weight 1A. Figure 7A and Figure 7B The left end portion of the keyboard weight 1A is located at the left end portion. Additionally, a locking part 3R, similar to the locking part 3L described above, is located at the other end portion of the hollow component 3 of the keyboard weight 1A. Figure 7A and Figure 7B (at the right end of the middle).

[0041] Each of the locking portions 3R and 3L is formed to protrude inward in a radial direction at the end portion of the hollow member 3. For example, these locking portions 3R and 3L are formed by means of having such Figure 8 The cross-shaped pressing part 31 shown in the figure is formed by the sewing machine 30 pressing the hollow part 3 from both sides.

[0042] Next, we will refer to Figures 9 to 12 The method for attaching the keyboard weight 1A to key 10 is described. First, as... Figure 9 As illustrated in the figure, similar to the method of attaching the keyboard weight 1 described above, a weight body 2 and a hollow component 3 are prepared (weight component preparation step), and a key 10 for attaching the keyboard weight 1A is prepared (key preparation step).

[0043] Next, as Figure 10A As shown in the diagram, the main body 2 of the weight is inserted into the hollow component 3 to create the keyboard weight 1. Then, by using... Figure 8The stitching machine 30 described above presses the hollow part 3 of the keyboard weight 1 from both sides to manufacture... Figure 10B The keyboard weight 1A shown in the figure is a keyboard weight 1A with multiple locking parts 3L and 3R at the two ends of the hollow part 3 (keyboard weight manufacturing step).

[0044] Next, as Figure 11 As illustrated in the diagram, the keyboard weight 1A, manufactured as described above, is inserted into the insertion hole 11a of the key 10 (keyboard weight insertion step). Then, using the stitching machine 20 described above, the keyboard weight 1A inserted into the insertion hole 11a is pressed from both the left and right sides of the key 10 by the pressing portions 21 and 21 (keyboard weight attachment step).

[0045] Figure 12 It is consistent with the description above. Figure 6B A similar view is shown, illustrating the state in which the keyboard weight 1A is attached to the key 10 by pressing. In this method of attaching the keyboard weight 1A, similar to the case of attaching the keyboard weight 1 described above, buckling occurs from the thin portion 4 due to pressing, and in the hollow component 3, the peripheral portion (deformable portion 6) including the thin portion 4 deforms inward and outward in the radial direction.

[0046] That is, such as Figure 12 As illustrated, the deformable portion 6 of the hollow component 3 deforms relatively large outward in the radial direction to engage with the key body 11, and deforms slightly inward in the radial direction to engage slightly with the weight body 2 or forcefully press against the outer peripheral surface of the weight body 2. As a result, the keyboard weight 1A is firmly attached to the insertion hole 11a of the key body 11. In the state where the keyboard weight 1A is attached to the key 10, similar to the keyboard weight 1 of the first embodiment described above, the two end surfaces of the hollow component 3 are substantially flush with the left and right surfaces of the key body 11.

[0047] As described above, the keyboard weight 1A according to this embodiment can achieve effects similar to those of the keyboard weight 1 of the first embodiment described above. Furthermore, in the keyboard weight 1A, the weight body 2 is immovably locked along the length of the hollow member 3 by a plurality of locking portions 3L and 3R provided at both ends of the hollow member 3. Therefore, when the keyboard weight 1A is pressed and attached from both sides along the length of the hollow member 3 while inserted into the insertion hole 11a of the key 10, the weight body 2 can be stably attached without shifting along the length of the hollow member 3.

[0048] Please note that the present invention is not limited to the embodiments described above and can be implemented in various ways. For example, copper and brass have been exemplified as the constituent materials of the main body 2 and hollow component 3 of the keyboard weights 1 and 1A, but the present invention is not limited to this, and other materials besides lead can also be used, such as metals or synthetic resins with relatively high specific gravity other than lead, as well as composite materials of such metals and synthetic resins. For example, when a synthetic resin (e.g., polypropylene) with a relatively low elastic modulus is used as the hollow component 3, or when a hollow component 3 made of synthetic resin is used, locking portions 3L and 3R can be provided at the two end portions by pressing the two end portions while heating the two end portions of the hollow component 3.

[0049] Furthermore, the detailed construction of the keyboard weights 1 and 1A, the weight body 2, and the hollow component 3 described in the embodiments are merely examples and can be appropriately modified within the scope of the spirit of the present invention.

Claims

1. A keyboard weight, which, in an inserted state, is non-movably attached to a through-hole of a predetermined diameter formed in the keys of a keyboard instrument, the keyboard weight comprising: The main body of the heavy object is made of materials other than lead and is formed into a cylindrical shape with a predetermined diameter and a predetermined length. as well as A hollow component, made of a material other than lead, is formed into a cylindrical shape having an inner diameter allowing the main body of the weight to be inserted into the hollow component, an outer diameter allowing the hollow component to be inserted into the embedding hole, and a predetermined length longer than the main body of the weight. The component is inserted into the embedding hole when the keyboard weight is attached to the key and the main body of the weight is inserted inwards. The hollow component has a thin portion that extends along the entire circumferential direction, has a predetermined width along the length direction, and has a predetermined thickness smaller than the thickness of the other portions of the hollow component. The hollow component is configured such that when the keyboard weight is attached to the key, the hollow component is pressed from both sides along the length direction, thereby buckling starting from the thin portion.

2. The keyboard weight according to claim 1, wherein, The thin portion is formed by providing a groove located at the center of the hollow component along the length direction and opening outward in the radial direction.

3. The keyboard weight according to claim 2, wherein, The hollow component into which the weight body is inserted has locking portions at both ends, the locking portions being formed to protrude inward along the radial direction and lock the weight body immovably along the length direction of the hollow component.

4. A key, comprising: The key body, made of wood, extends in the front-back direction and is configured to be oscillating, wherein the key body has an insert hole at a predetermined position in the front-back direction that penetrates the key body in the left-right direction; as well as A keyboard weight is attached by being pressed from both the left and right sides of the key body while it is inserted into the embedding hole of the key body, wherein... The keyboard weight includes the keyboard weight according to any one of claims 1 to 3.

5. A method for attaching a keyboard weight, comprising: Preparation steps for preparing the heavy object component according to claim 1, including the main body and hollow component; Key preparation steps for preparing a key with an embedding hole as described in claim 1; The keyboard weight manufacturing step involves inserting the main body of the weight into the hollow component to manufacture the keyboard weight. The keyboard weight is inserted into the key's embedding hole in the keyboard weight insertion step; as well as The following keyboard weight attachment steps are performed: the keyboard weight is attached in a fixed state to the key's embedding hole by pressing the keyboard weight from both sides along the length direction to cause bending starting from the thin portion.

6. The method according to claim 5, wherein, In the keyboard weight manufacturing step, while the weight body is inserted into the hollow component, the two end portions of the hollow component are pressed from both sides to deform so as to protrude inward in the radial direction, and to form a locking portion for locking the weight body immovably along the length direction of the hollow component.

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