JPS60230700A - Body for drum - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to copper for drums that has good vibration efficiency and improved sound characteristics.

[Prior art]

A drum is a cylindrical body made of wood, metal, etc. The drum head is supported and tensioned with uniform force in the openings at both ends of the body, and the sealed air column acts as a vibration transmission medium to generate the drum sound. When one drum head is struck, the air column transmits the vibration to the other drum head, and when the other drum head vibrates, the air column transmits the vibration to the other drum head. In this way, both drum heads are caused to vibrate repeatedly. Therefore, the drum must maintain its shape stably, not be deformed by climatic conditions or the tension of the drum head, have little deviation in articulation, and not cause self-vibration or self-absorption. Furthermore, the sound quality of the drum varies significantly depending on the material of the body; when it is made of wood and plywood, it has a calm sound, while when it is made of metal, it has a light and bright sound.

By the way, since the support tension means for the drum head is attached to the outer peripheral surface of the drum head, the natural vibration of the drum head itself, which has poor vibration efficiency, is hindered. As a result, the sound volume was reduced, noise was generated that lacked the power of the sound, and the acoustic characteristics were deteriorated.゛Also, in order for the drum to maintain its function as a vibration resonator, it needs to be light and thin, but in that case, if it is made of wood or plywood, the edge of the drum that serves as the fulcrum of the drum head, In other words, since the opening end has low rigidity, the drum head cannot be vibrated efficiently.

[Summary of the invention]

This invention was made in view of the above points, and includes a drum body made of an acoustic material with a relatively light specific gravity and a high Young's modulus, and a drum body made of an acoustic material with a specific gravity that is higher in hardness (higher strength) than the drum body. By constructing the sun ring made of heavy material and fitted and fixed into the opening of the drum body, the fulcrum part for the drum head has high rigidity, the drum head can be vibrated efficiently, and the acoustic characteristics are improved. It is intended to improve the drum state side.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

〔Example〕

FIG. 1 is a sectional view showing an embodiment of a drum equipped with a drum according to the present invention. The drum, which is designated as a whole by the symbol 1, has a barrel 2.
．． A pair of upper and lower drum heads 3A and 3B are stretched at both end openings of the drum 2 with a predetermined tension.

It is generally composed of support tension means 4 and the like for the drum heads 3A and 3B.

The cylinder body 2A has a thin wall made of an acoustic material having a relatively light specific gravity and a high Young's modulus, and the cylinder body 2A is formed in an annular shape from a material having a high hardness and a heavy specific gravity. are respectively fitted into the openings at both ends and glued,
A pair of upper and lower sun wheels 2 firmly fixed with set screws, etc.
It is composed of B1, 2B2.

The acoustic material of the trunk body 2A is spruce.

Wood such as cedar, lumber core plywood, plywood such as laminated metal plate (veneer board), glass fiber reinforced plastic (GFR)
P), fiber reinforced plastics (FRP) such as carbon fiber reinforced plastics (CFRP).

A laminate of aluminum, a light alloy such as an aluminum alloy, FRP, wood, or metal and plastic is used, and has a thickness of 6 to 7 mm or less.

On the other hand, the materials for each sun ring 2B1 and 2B2 are birch,
Wood such as beech and maple, high-density GFRP.

FRP such as CFRP and light metals such as aluminum and zinc are used.

Each of the sun rings 2B1 and 2B2 has a substantially J-shaped cross-sectional shape, with a small curvature, by forming a fitting groove 5 on the inner surface into which the outer peripheral surface of the opening of the trunk body 2A fits. Each of the drum heads 3 at the edge portion a formed on the curved surface
It supports the peripheral parts of A and 3B.

In this case, in this embodiment, each sun ring 2B1, 2B2 is fitted and fixed on the outer circumferential surface of each opening of the trunk body 2A, but as shown in FIG. It may be formed into a surface and fitted and fixed to the inner circumferential surface of the opening of the trunk body 2A. Further, the cross-sectional shape is not limited to a substantially J-shape, but may be rectangular as shown in FIG. 2(b) without the fitting groove.

The support tension means 4 includes a pair of upper and lower head frames 6m and 6b that are fitted around the outer periphery of each opening of the drum head 2 and hold the peripheral edge of each drum head 3A and 3B, and each head frame 6a.
The head frame 6m is fitted onto the outer periphery of the head frame 6b, and the head frame 6m is connected to the body 2.
a pair of upper and lower clamping frames 7m and 7b that press toward the center of the
A plurality of lugs 8 disposed on the outer peripheral surface of the holder 2 and a plurality of fasteners for fixing each of the clamping frames 7a and 7b to each of the dugs 8 are comprised of bolts 9 and the like. The tension of each of the drum heads 3A and 3B is adjusted by rotating the port 9 and the tightening frame 7a.

By moving the drum 7b up and down, it can be freely adjusted, thereby changing the tone and pitch of the drum 1.

Each of the lugs 8 is used in common for the upper and lower drum heads 3A and 3B, and the upper and lower mounting portions 8a and 8b are firmly fixed to the outer peripheral surface of each of the sun wheels 2B1 and 2B2 with set screws (not shown). The two main bodies were kept in a non-contact state. This is extremely effective in effectively vibrating the central part of the body body 2A, that is, the part other than the opening where the sun rings 2B1 and 2B2 are fitted and fixed, and exhibiting its function as a vibration resonator 7. And it is important.

It should be noted that each opening of the drum 2 has a high rigidity, so that it almost functions as a vibration resonator, and mainly functions as a fulcrum for each of the drum heads 3A and 3B.

Thus, when the drum 1 with such a cylinder 2 is loaded, the cylinder 2
Since the rigidity of the opening is large, the loss of vibration energy at the opening is small, and each drum head 3A, 3B can be vibrated efficiently. In addition, since the central portions of the two torso bodies are not in contact with the lugs 8 that impede their vibration, they vibrate well and fully exhibit their function as a vibration resonator.

FIG. 3 shows the damping characteristics obtained by this invention, and r
, n, and m are the fundamental wave, lower harmonics, and higher harmonics, respectively.
This is the attenuation characteristic of the overall sound of the drum.

As is clear from this figure, the sound rises quickly in 9.
The attenuation of the fundamental wave and low-order overtones (1) is small, and the attenuation of high-order overtones (It) is faster, so the drum sound has a long sustain but is crisp and has a clear pitch. It is possible to improve the acoustic characteristics of the drum.

In addition, since each drum head 3A, 3B is held by a highly rigid sun wheel 2B1.2B2, the drum body 2 is not deformed by the tension of the drum heads 3A, 3B, and therefore the drum body 2A is lightweight.

It can be formed thin and can effectively function as a vibration resonator. Furthermore, if there is less deformation, high roundness can be maintained and deviations in articulation can be prevented.

Although the above embodiment describes a drum in which the drum heads 3A and 3B are attached to the openings at both ends of the drum body 2, the present invention is not limited to this, and the drum head may be attached to only one opening, such as a tom-tom. Of course, it can also be applied to. In this case, instead of fitting and fixing the sun rings to the openings at both ends of the drum body, it is also possible to fit and fix them only to the opening on the side where the drum head is stretched.

[Effects of the Invention] As explained above, the drum layer according to the present invention includes a drum body formed thinly of an acoustic material having a relatively light specific gravity and a high Young's modulus, and a drum body having a high hardness and a high specific gravity. Since the drum head is made of material and is fitted and fixed into the opening of the drum body, the opening of the drum body is more stable than the central part and is less likely to vibrate. can be vibrated efficiently with less loss of vibration energy,
Vibration is transmitted to the center of the body without loss, and the center of the body functions as a vibration resonator, so the sound rises quickly, the pitch is clear, and the sustain is long and crisp. This improves the acoustic characteristics of the drum. In addition, the structure is simple and easy to manufacture, which has great effects.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a drum equipped with a drum according to the present invention, FIGS. 2(a) and (b) are main part cross-sectional views showing other embodiments of the present invention, and FIG. The figure is a diagram showing the damping characteristics of the drum according to the present invention. 1... Drum, 2... Torso, 2A... Torso body, 2B1.2B2... φ sun ring, 3A, 3B, Calligraphy...
Drum head, 4... Clear support tension means, 6a, 6
b... Head frame, γa, 7b... Clamping frame, 8
...Lug, 9...Tighten with bolt. Patent applicant Masaki Yamakawa (and 2 others), agent of Nippon Musical Instruments Manufacturing Co., Ltd.

Claims (5)

[Claims] (1) A cylindrical body made of a thin wall made of an acoustic material with a relatively light specific gravity and a relatively high Young's modulus, and an annular opening of the body made of a material with higher hardness and heavier specific gravity than the body. and a sun wheel which is fitted to support the drum head and is integrally fixed to the drum head.
・°ram barrel 0 (2) The copper for drums according to claim 1, wherein the acoustic material is wood such as spruce or cedar. (3) The copper for drums according to claim 1, wherein the acoustic material is plywood such as laminated plywood or lumber core plywood. (4) The copper for a drum according to claim 1, wherein the acoustic material is a fiber-reinforced plastic such as a glass fiber-reinforced plastic or a carbon fiber-reinforced plastic. (5) The copper drum according to claim 1, wherein the music material is a light metal such as aluminum or aluminum alloy.