JP2011022546A - Aging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: a wooden musical instrument is known to have an aging phenomenon in which drying and deterioration of a wood part, adhesive, varnish, or the like gently progress after manufacturing, the aging period is generally long, the aging is known to be affected by played music or the history of sound quality, and much play and time are required for allowing a user to obtain this aging effect after purchasing of a new article. <P>SOLUTION: The aging device extracts the aging effect of the wooden musical instrument or the like, and aging that is not sufficiently controlled does not necessarily have a good effect on the musical instrument. An object is put into an internal space surrounded by composite walls that can be expected to have moisture permeability and insulating/sound insulation/sound absorption property for accelerating drying and deterioration close to natural ones of the musical instrument or the like, and the accelerating effect is added to the drying and deterioration by acoustic excitation by a specific music. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

An object or product having a material of a wooden musical instrument or a natural plant / animal has a small chamber such as a cell as its tissue, and the characteristics of the material change due to drying or alteration of the liquid in the small chamber over time. In addition, these materials are subjected to a change with time of the coating material such as varnishes used as a surface treatment and an adhesive such as glue for bonding the materials and relaxation of residual stress. This is an area of technology related to aging that controls and promotes these changes over time.

Especially in the case of wooden instruments, the change over time is due to the relaxation of residual stress, gentle drying, the improvement of the elastic coefficient and the reduction of the damping characteristics, the natural frequency and damping characteristics that determine the sound quality of the instrument, and the vibration transfer characteristics. Cause changes. Therefore, it is said that the richness of the sound, the sound, and the volume change, and generally the tendency to go in the preferred direction is large. This phenomenon is called aging of musical instruments, and the effect is expected when playing musical instruments for many years.

As a conventional technology, not only wooden musical instruments described here but also electronic musical instruments with built-in metal musical instruments and electronic circuits are said to have improved sound quality by performing conditioned performance after production. There are reports. However, at a well-known level, the verification is limited to the auditory scope, and there is no clear result in the engineering approach for that reason.

The main factor of the aging effect is the relaxation of the internal residual stress due to the tightening and fixing work during bonding and assembly. The magnitude of the internal stress inside the structure, such as the tension of the string, affects the vibration characteristics. give. As the second factor, reduction of the vibration damping characteristics in the wood structure and glue adhesive and improvement in elastic modulus due to alteration (crystallization promotion, etc.) due to reduction of moisture content and change with time, etc. can be raised.

It is considered that the aging effect of a musical instrument or the like often depends on a vibration pattern or a vibration mode excited when a sound is produced. There are cases where the parts that vibrate well are promoted to dry or change their quality. In general, there is an excitation method that directly applies vibration to the main body of a musical instrument or the like, but there are problems such that the instrument or the like is likely to be scratched or the excitation location may be unevenly distributed due to local excitation. .

In non-musical performance, the so-called messy sound quality becomes noticeable. Also, if not played very much, it is said that the sound richness and reverberation does not change over time, so that the instrument does not sound. There is a tendency for the variation as a musical instrument to increase due to the influence of the number of performances of musical instruments, etc. and the performance of “performance, poor”.

In addition, standing waves in a narrow internal space (17) are always subjected to forced excitation at a specific frequency, aging sensitive to the sound, and the possibility of aging that lacks musical balance There is.

With regard to the progress of the aging effect, there are cases where musical instruments and the like that are difficult to be in good condition are produced depending on how the aging period is played. In addition, rapid drying that saves time is extremely likely to cause distortion in musical instruments. When a rather rapid drying is performed as a general heating method, local stress is applied, and in some cases, damage such as cracks may be caused.

As described above, the mechanism of the aging effect is firstly the release of residual stress, and secondly it relates to drying and alteration such as reduction of water content and change with time. These substances are woody hemicellulose and gelatin of gelatin, and change depending on moisture and temperature.

Glue is an adhesive that fixes using changes in sol (liquid) and gel (solid), but has a property of softening when the temperature rises. In order to release the internal stress after product assembly, the local strain is gradually corrected due to the heat generated by vibration.

When these settle down, the moisture content decreases and the hemicellulose, which is a buffer component in wood, settles, and the crystallization of the cellulose improves the elastic modulus, the damping characteristic decreases, the volume sensitivity and the sound reverberation improve . However, if you do it too much, there will be more sounds with less attenuation in the treble part, which may lead to loud sound quality.

Acoustic excitation can be performed without contact and can be combined with aging propulsion. That is, it is not necessary to specify the excitation location, and by installing a specific acoustic excitation speaker, it is possible to apply it alone or to a plurality of objects. Due to the vibration, the portion that vibrates with good probability due to the vibration pattern is more likely to vibrate due to the aging being advanced by the vibration. That is, it becomes easy to make a sound. Here, in principle, in the case of a stringed instrument, it is preferable to constrain the string so that the string is not stretched or vibrated. Only certain scales may be emphasized.

It is possible to freely select a song or a famous performance suitable for the target instrument and perform acoustic excitation. Depending on the case, in order to narrow down to a certain extent of Jeanne music or a specific Jeanne, it is possible to newly prepare a song set for acoustic excitation instead of a specific song.

In addition, even when acoustic excitation including these large sounds is performed in the internal space, the sound insulation and sound absorption capacity of the laminated layer by the composite heat insulating material is large (Fig. 7), and sound leakage in the sound field around the installation of the device Can be at a problem-free level.

In addition, in order to shorten the time related to drying, it is possible to perform aging continuously and efficiently in an unattended state by setting appropriate conditions based on vibration and high temperature / low humidity conditions in a state close to the history of actual players. It is.

In order to reduce the standing wave in the internal space, first, there is a means for the inner wall material to appropriately absorb sound and to have an effect of attenuating the standing wave. Secondly, a means for providing a layout in which there is no facing inner wall surface that matches the normal direction of the surface so that the wavelength of the standing wave changes depending on the location by providing a curved surface or inclined surface on the inner wall surface There is. Thirdly, there is means for adding unevenness of the inner wall surface so that the segmented piece-like reflector is installed on the inner wall surface or the reflection direction is irregularly reflected. Fourth, means for installing a sound absorbing material having a large sound absorbing effect on the inside of the inner wall surface. The sound absorbing material (8) is appropriately installed in the space, and if possible, a sound absorbing material is provided at a location where the amplitude of the sound pressure of the standing wave is large. Preferably there is a material. In some cases, it is effective to dispose the nonwoven fabric sheet in a warm manner in the internal space.

Musical instruments and the like placed in a high-temperature and low-humidity atmosphere in the internal space (17) are coupled with vibrations to be applied and undergo aging such as drying. The appropriate drying function at this time utilizes moisture absorption / release properties and moisture retention (FIG. 5) due to materials existing in nature. That is, as the filling heat insulating material (1), cellulose fiber (FIG. 6) such as wood pulp material combined with boric acid or the like combined with anti-corrosion, mold prevention, water repellency, etc., or a material of the same material is used. A structure (7) in which (2) and the outer wall material (3) are stacked on the sandwich is adopted. Furthermore, it is calculated | required that a filling heat insulating material (1) also has sound insulation and sound absorption property and moisture retention.

The inner wall material (2) has a moisture-absorbing and sound-absorbing structure that does not emphasize standing waves due to internal dimensions, and the outer wall material (3) has a waterproof or sound-insulating wood system or equivalent characteristics. Shall have. Further, a door for taking in and out the object is provided in the internal space (17), and a similar laminated structure or a structural material equivalent thereto is used.

The water extracted by drying in the internal space (17) at a relatively high temperature (a high temperature of about several tens of degrees Celsius with respect to the ambient temperature) and a low humidity (a humidity of about 25 to 60%) is a water vapor state (6). Then, it is discharged from the surface of the outer wall material (3) through the filling heat insulating material (1) from the inner wall (2) as a humidity increase due to the difference between the inner and outer temperatures. In some cases, the pressure in the internal space (17) can be slightly increased to assist the moisture permeability of the water vapor (6).

Further, when a large amount of moisture is released, condensation may occur in the heat insulating material layer. In this case, it is effective to provide a gap between the center filled heat insulating material (1) and the outer wall material (3) and provide an air passage (5) for circulation with the outside air. The air circulation is generally a natural convection method, but a mechanical forced circulation method is also possible.

The vibration caused by the appropriate vibration applied to the object in an appropriate high temperature and low humidity atmosphere has the effect of promoting aging for drying and alteration. Usually, an aging period requiring a time of about 1 to 10 years is possible in several weeks to several months.

In addition, the composite wall (7) composed of the above-mentioned filled heat insulating material (1) and the inner and outer walls (2) and (3) has moisture permeability, and the aging of the object placed in the inner space due to the temperature difference between the inside and outside. However, the moisture content of the object at that time has a function of adjusting the water content to an appropriate value by absorbing water in the case of the clause by the function of drying moisture. That is, it is also effective for rehabilitation of musical instruments that are too dry.

In order to achieve a commitment to the sound quality of musical instruments, it is possible to customize aging that matches the Jeanne and musical composition of the music being played. In addition, a case-type device (FIG. 8) that can be carried alone can be compatible with performance in the aging process.

FIG. 1 shows a typical example of an aging apparatus. A wooden musical instrument, here a guitar (13), which is the object of aging, is placed in an internal space (17) surrounded by a box-shaped composite wall (7), and a heater is used so that the temperature is higher than the outside and has a predetermined temperature difference. (9) is installed. Further, a fan (10) may be installed in order to make the temperature of the internal space (17) uniform. Further, some members having high sound absorption rate are arranged so that no standing wave is generated in the internal space (17), and music that matches the desired music Jeanne is played by the speaker (11), and acoustic excitation is performed.

When dew condensation occurs in the composite wall shown in FIG. 2, an air passage (5) is provided between the outer wall material (3) and the filled heat insulating material (1) as shown in FIG. It shows a structure that prevents condensation. At that time, no condensation occurs due to the balance between the temperature distribution and the amount of water vapor as shown in FIG.

FIG. 8 shows a case-shaped aging device for storing a musical instrument for storage or transportation intended for a single musical instrument or the like. Here, a battery (14) is mounted for carrying.

Wooden instruments are said to produce better sound when played more firmly than immediately after manufacture. I want a good instrument, but it takes a lot of effort to play until the aging effect is achieved, and many people step on the purchase. In the case of second-hand instruments, the history is unknown, and there are no scratches, so there is no decisive advantage. Recently, elderly musical instruments have attracted attention as a countermeasure against dementia, but aging for a long period is difficult physically, and it is required to produce good sound immediately. Warehouse type, which also serves as an inventory of completed musical instruments at the manufacturer of the instrument, inventory at the musical instrument store, large box or stock room type as a service to the purchaser, portable case type for individual owners and professional musicians Etc. can be provided, and the demand can be expected.

Aging equipment Composite wall structure 1 Composite wall structure 2 Composite wall temperature distribution and water vapor volume Moisture absorption and desorption of filled insulation Comparison of heat transfer coefficient of insulation Sound absorption characteristics of cellulose fiber Single case aging device

DESCRIPTION OF SYMBOLS 1 Filling heat insulating material 2 Inner wall material 3 Outer wall material 4 Moisture permeable intermediate wall material 5 Air passage 6 Water vapor 7 Composite wall 8 Sound absorbing material 9 Heater 10 Fan 11 Speaker 12 Non-woven sound absorbing sheet 13 Wooden musical instrument (guitar)
14 Battery 15 Case body 16 Case lid 17 Internal space

Claims (9)

Standing wave based on moisture permeability and internal dimensions with moisture absorption / release properties and sound insulation / absorption properties composed of fiber with small voids inside and cellulose fiber made of granular material or material with equivalent characteristics The surrounding wall is formed by a composite wall laminated with an inner wall material with a sound absorption rate that does not emphasize the sound and a wooden system with waterproof and moisture permeability and sound insulation or an outer wall material with equivalent properties, and has the same characteristics as the composite wall. A structure that constitutes a box-shaped storage space with a door that can be opened and closed made of wall material, with a heater that maintains the internal space at a higher temperature than the outside, and objects that have wooden musical instruments or natural plant / animal materials A device that puts products, etc., and at the same time plays music by an acoustic device in the internal space and performs acoustic excitation The apparatus according to claim 1, wherein the apparatus has a function capable of selecting and adjusting the temperature of the internal space, the volume for the magnitude of the acoustic excitation, or the music for the acoustic excitation. In order to reduce the standing wave in internal space, the inner wall surface is provided with the curved surface or the fragmented piece-like reflecting plate is installed in the inner wall surface, or inner A device with a sound-absorbing material with a large sound-absorbing effect inside the wall The apparatus according to claim 1, 2 or 3, further comprising a blower for circulating internal air. 5. The apparatus according to claim 1, 2, 3, 4, wherein the internal pressure is slightly increased by a blower using a rotary fan, a small air compressor or the like. In the apparatus according to claim 1, 2, 3, 4, 5, a mesh-like sheet, a moisture-permeable sheet or a plate similar to the outer wall is disposed on the outer surface portion of the filled heat insulating material, and between the outer surface and the outer wall. A device that circulates air to the outside by providing a gap 4. A device according to claim 1, 2, or 3, wherein a single storage or transport case for the target musical instrument has a small space between the musical instrument and the inner wall, and the case is compared with the main sounding part of the musical instrument. Or a device with a function that can turn on / off acoustic excitation by opening and closing the case by installing multiple small acoustic excitation speakers 8. The apparatus according to claim 1, 2, 3, 7, wherein the battery is built in and has functions such as single or charging or direct power supply from an external power source, solar power generation by a panel 9. The apparatus according to claim 1, 2, 3, 7, 8, wherein the internal heater has an on / off function or the internal heater is omitted.

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