JPH11288268A - Grand piano frame mounting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a frame mounting device for a grand piano, which has a simple configuration and can mount a frame to a back assembly with high accuracy in a vertical direction. SOLUTION: A plurality of frame base installation holes 14 are formed at predetermined positions at positions along the outer periphery of a back assembly 1, and a plurality of bolt holes 10 are provided at a plurality of positions of a frame F corresponding to the frame base installation holes 14. A plurality of frame bases 11 having a predetermined height greater than the depth of the frame base installation holes 14 and having the bolt holes 12 formed therein.
And a plurality of frame bases 11 each of which is gap-fitted into the frame base installation hole 14 and is fixed to the stack 2.
With the frame F placed on the frame base 11,
The bolts are passed through the bolt holes 10 and 12 from above, respectively.
And a plurality of mounting screws 9 for fixing the frame F by being tightened with respect to.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for mounting a frame of a grand piano for mounting a frame on a base assembly in which stacks, supports, sound boards, and the like are assembled.

[0002]

2. Description of the Related Art The frame of a grand piano constitutes a back mechanism together with a stack and supports, and plays a role of supporting the tension of a string attached to the frame.
Conventionally, it is generally attached to a back assembly as shown in FIGS. This back assembly 1
After assembling the unloading 2, the strut (not shown), the back frame 3, and the like, the long piece 4 and the short piece 5
Is attached to the soundboard 6 to which is attached.

In order to mount the frame F, first, a plurality of sets of holes 7 each including three holes 7a, 7b, 7a are formed at a plurality of predetermined locations along the outer periphery of the upper surface of the back assembly 1, for example. A third drill is formed from the upper surface of the soundboard 6 to the stack 2. Out of the set of holes 7, the holes 7a, 7a on both sides are dowel holes, the diameter of which is 13 m, which is slightly smaller than the dowel 8.
m, and the depth is based on the lower surface of the loading 2
Is set as the predetermined height A1. On the other hand, the central hole 7
b is a pilot hole of the mounting screw 9 and its diameter and depth are
It is set to a value that can be tightened by the mounting screw 9. Next, after a wooden dowel 8 having a predetermined length is driven into each dowel hole 7a to the bottom, a frame F is placed on the dowel 8 and a mounting screw 9 is inserted into a bolt hole 10 and a pilot hole 7b formed in the frame F in advance. The frame F is attached to the back assembly 1 by passing and tightening.

[0004]

However, in such a conventional mounting method of the frame F, since the dowel 8 is driven into the dowel hole 7b, the impact makes it easy for the dowel 8 to sink into the load 2. Further, in order to reliably prevent the breakage of the pile 2 due to the impact, a thin dowel 8 must be used. Therefore, a load acting per unit area of the dowel 8 at the time of driving or tightening the mounting screw 9 is required. As a result, the dowel 8 is more easily immersed in the loading 2. Further, since the diameter of the dowel hole 7b is also small, it is difficult to finish the bottom surface of the dowel hole 7b to an accurate flat surface. As a result, the installation height A1 at the lower end of the dowel 8 becomes inaccurate, and accordingly, the accuracy of the height A2 of the frame F placed thereon is also reduced. For example, it is difficult to adjust the frame pressure thereafter. And other problems occur.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and has a simple structure, and can attach a frame to a back assembly with high accuracy in a vertical direction. The purpose is to provide.

[0006]

SUMMARY OF THE INVENTION To achieve this object, the present invention is an apparatus for mounting a frame of a grand piano for mounting a frame on a back assembly including a stack, comprising: A plurality of frame base installation holes are formed at a plurality of positions along the outer circumference up to a predetermined height of stacking, and a plurality of bolt holes are formed at a plurality of positions of the frame corresponding to the plurality of frame base installation holes, A plurality of frame bases having a predetermined height greater than the depth of the frame base installation holes and having bolt holes penetrating in the vertical direction, each of which is gap-fitted into the plurality of frame base installation holes, and A plurality of frame bases to be fixed, and a plurality of bolt holes and a plurality of frame bases of the frame with the frame mounted on the plurality of frame bases. Each passed from above into the scan of the bolt holes, it is characterized by comprising a plurality of mounting screws that secure the frame by being tightened against SekiAge.

According to this mounting device, the frame is mounted on the base assembly as follows. That is,
A plurality of frame base installation holes are formed at a plurality of positions along the outer periphery of the upper surface of the base assembly to a predetermined height of the stacking, and a plurality of bolt holes corresponding to these are formed in the frame in advance. Then, a frame base having a predetermined height is clearance-fitted into each frame base installation hole and fixed to the bottom surface, that is, the stack, and then the frame is placed on the frame base projecting upward from the base assembly, and the frame and the frame Pass the mounting screws through the bolt holes in the base,
The frame is attached to the base assembly by tightening and securing against the unloading.

Thus, in the mounting device of the present invention, the frame is mounted using the frame base instead of the conventional dowel. Unlike the case of a dowel, this frame base is fitted into the gap without being driven into the frame base installation hole. In addition, since the frame base is not driven, there is no risk of breaking the pile, so that the cross-sectional area of the frame base can be made larger than that of the dowel. As a result, the load acting on the unit area of the frame base at the time of tightening the mounting screws is reduced, and the frame base is hardly sunk into the stack when the frame is mounted.

In addition, since the size of the frame base installation hole becomes large, it is easy to finish the bottom surface to an accurate flat surface, so that the bottom height of the frame base installation hole becomes accurate. As a result, the height of the frame, which is determined as the sum of the height of the bottom surface of the frame base installation hole and the height of the frame base, is accurate, and the frame can be accurately attached to the back assembly in the vertical direction.

[0010] In this case, the frame base has a pair of tucker holes vertically penetrating on both sides of the bolt hole, and the lower surface is bonded to the stack and the tucker driven into the stack via the tucker hole. Is preferably fixed to the stack.

In this configuration, since the frame base is firmly fixed to the stack by bonding and tucker, when the frame is vibrated or raised in the manufacturing process of the piano after the frame is mounted. In such a case as well, it is possible to stably maintain a state in which the frame is accurately mounted.

In these cases, the frame base mounting holes are
It is preferable that the frame base is constituted by a long hole extending along the outer periphery of the stack, and the frame base has a plane shape similar to the frame base installation hole.

In this configuration, a relatively large area of the frame base installation hole extending in the length direction can be formed in the narrow stack, so that the bottom surface can be easily finished to an accurate flat surface. Also, since the cross-sectional area of the frame base can be ensured to be large, the amount of sinking into the stacking can be further reduced, and as a result, the mounting accuracy of the frame in the vertical direction can be further increased. Further, when the cross-sectional area of the frame base is increased, a space for forming the tucker hole can be easily secured.

In these cases, it is preferable that the frame base is formed of a resin molded product.

In this configuration, the frame base is set to ABS
It can be manufactured at low cost by using resin molded products such as
The frame base height accuracy can be obtained well.
Further, bolt holes and tucker holes of the frame base can be easily formed simultaneously with the molding.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the following description, the same components as those of the conventional grand piano described above are denoted by the same reference numerals.

1 to 4 show an apparatus for mounting a frame of a grand piano to which the present invention is applied. This mounting device replaces the above-described conventional dowel 8 with the frame base 1.
1, the frame F is attached to the base assembly 1.

As shown in FIGS. 2 and 3, the frame base 11 has an elongated flat shape composed of a straight portion and semicircular portions on both sides thereof. For example, the length L is 50 m.
m, width D is 15 mm, and height B is 12 mm. The frame base 11 is made of, for example, a resin molded product made of ABS or the like. Frame base 1
A bolt hole 12 is formed at the center of 1, and a pair of upper and lower tucker holes 13, 13 each having a smaller diameter than that of the bolt hole 12 are formed on both sides thereof in the vertical direction. The tucker hole 13 is formed as a counterbore. Has become. Since the frame base 11 has an elongated planar shape, such a tucker hole 13 is formed.
Space can be easily secured.

On the other hand, as in the conventional case, the base assembly 1 is constructed by assembling a stack 2, a support (not shown), a back frame 3 and the like, and then covering a long piece 4 and a short piece 5 so as to cover the upper surface thereof. The attached soundboard 6 is bonded, and each is made of a wooden material. A plurality of frame base mounting holes 14 are formed on the upper surface of the back assembly 1 at a plurality of predetermined positions extending from the inner peripheral portion to the right front side.

As shown in FIG. 3, each frame base installation hole 14 has a shape similar to the plane shape of the frame base 11 and is slightly longer than this (L1> L).
The frame base 11 is formed so as to extend along the outer periphery of the stack 2, so that the frame base 11 is fitted into the frame base installation hole 14 with a gap. Such an elongated frame installation hole 11 can be easily formed, for example, by moving the NC machine along the outer periphery of the base assembly 1. In addition, the depth of the frame base installation hole 14 is smaller than the height of the frame base 11 and
The lower surface of the stack 2 is defined as a reference, and the height from the lower surface of the stack 2 to the bottom surface of the frame base installation hole 14 is formed to be a predetermined height A (see FIG. 4). Further, on the bottom surface of the frame base installation hole 14, a pilot hole 14a of the mounting screw 9 is formed by an NC machine so as to extend downward.

The frame F is made of a cast product, and a plurality of bolt holes 10 similar to the related art are formed on its outer periphery at a plurality of positions corresponding to the frame base mounting holes 14.
It is formed by an NC machine.

With the above configuration, the frame F is attached to the base assembly 1 as shown in FIGS. First, after applying an adhesive G to the lower surface of the frame base 11, the frame base is inserted into each of the frame base mounting holes 14 with a gap, and a nylon tucker 15 is inserted into each of the tucker holes 13 and driven into the frame with, for example, an air gun. The base 11 is fixed to the bottom of the frame base installation hole 14, that is, the stack 2. In this state, the frame base 11 has its height and the frame base
The above relationship between the depth of the base assembly 1 and the depth of the base assembly 1 causes the base assembly 1 to protrude upward. Next, after placing the frame F on the projecting frame base 11, the frame F
The frame F is mounted on the base assembly 1 by passing the mounting screws 9 through the bolt holes 10 and 12 of the frame base 11 and tightening the mounting screws 9 to the stack 2.

As described above, according to the present embodiment, unlike the case of the conventional dowel 8, the frame base 11 is fitted with a gap without being driven into the frame base installation hole 14.
In addition, since the frame base 11 is not driven, there is no possibility that the unloading 2 is broken.
1 can be set larger, and in the embodiment, the elongated frame base 11 is installed along the stack 2. As a result, the load acting per unit area of the frame base 11 when the mounting screw 9 is tightened is reduced, and the frame base 11 is hardly sunk into the stack 2 when the frame F is mounted.

The frame base installation hole 14 is also used for the loading 2
The bottom surface can be easily finished to an accurate flat surface simply by moving the NC machine along the loading 2 and the bottom height A of the frame base installation hole 14 is also accurate. become. As a result, the height of the frame F is
Without being affected by the mounting condition of the frame base 11,
As a simple sum (A + B) of the bottom height A of the accurate frame base installation hole 14 and the height B of the frame base 11,
Is accurately determined, and thus the frame F is attached to the back assembly 1
Can be mounted with high accuracy in the vertical direction.

Further, since the frame base 11 can be firmly fixed to the stack 2 by the adhesion and the tucker 15, vibrations are applied to the frame F or the frame F is raised in the manufacturing process of the piano after the frame F is mounted. Even in the case where the frame F is broken, the state where the frame F is accurately attached can be stably maintained. Further, since the frame base 11 is made of a molded article of a resin such as ABS, the frame base 11 is inexpensive, and the bolt holes 12 and the tucker holes 13 are formed.
Can be easily formed at the same time as the molding, and the height accuracy of the frame base 11 can be obtained well.

The present invention is not limited to the embodiments described above, but can be implemented in various modes.
For example, in the embodiment, the frame base 11 is made of a resin molded product, and the tucker 15 is made of nylon. However, it is of course possible to change these materials to other appropriate materials. For example, frame base 11
And a tucker made of iron may be used. In addition, it is possible to appropriately change the detailed configuration and the like within the scope of the present invention.

[0027]

As described in detail above, the apparatus for mounting a frame of a grand piano according to the present invention has a simple structure and has an effect that the frame can be mounted on a back assembly with high accuracy in the vertical direction.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a state before a mounting device for a frame of a grand piano according to an embodiment of the present invention.

FIG. 2 (a) a plan view of a frame base, and (b)
It is sectional drawing which follows the line II-II.

FIG. 3 is a perspective view of a frame base and a frame base installation hole.

FIG. 4 is a sectional view after a frame is attached.

FIG. 5 is a perspective view corresponding to FIG. 1 of a conventional mounting device.

FIG. 6 is a sectional view of a conventional mounting device after mounting.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base assembly 2 Stacking 9 Mounting screw 10 Frame bolt hole 11 Frame base 12 Frame base bolt hole 13 Tucker hole 14 Frame base installation hole 15 Tucker F Frame G Adhesive

Claims (4)

[Claims] An apparatus for mounting a frame of a grand piano for mounting a frame on a back assembly including stacking, wherein a predetermined height of the stack is provided at a plurality of positions along an outer periphery of an upper surface of the back assembly. A plurality of frame base installation holes are formed, and a plurality of bolt holes are formed at a plurality of positions of the frame corresponding to the plurality of frame base installation holes, and a predetermined larger than the depth of the frame base installation hole. A plurality of frame bases having a height and formed with bolt holes penetrating in the up-down direction, a plurality of frame bases each being gap-fitted in the plurality of frame base installation holes, and fixed to the stack, With the frame placed on the plurality of frame bases, the plurality of bolt holes of the frame and the bolts of the plurality of frame bases are provided. A plurality of mounting screws, each of which is passed through from the upper side to the tilt hole, and is fixed to the stack by fixing the frame, and a plurality of mounting screws. 2. The frame base has a pair of tucker holes vertically penetrating on both sides of the bolt hole, and a lower surface is adhered to the stack and driven into the stack via the tucker hole. The grand piano frame mounting device according to claim 1, wherein the frame is fixed to the stack by a tucker. 3. The frame base installation hole is formed by an elongated hole extending along the outer periphery of the stacking, and the frame base has a plane shape similar to the frame base installation hole. The mounting device for a grand piano frame according to claim 1 or 2, wherein 4. The apparatus according to claim 1, wherein the frame base is formed of a resin molded product.