Musical instrument with a body made of polyurethane foam

#The present invention relates to a musical instrument and/or acoustic apparatus body part of which is to be made of polyurethane foam, more particularly to the musical instrument and/or acoustic apparatus, such as an electric guitar, a piano, an amplifier, whose casing or entire body is to be made of polyurethane foam, which has good property of moulding and processing and does not result in crack and twist.

#According to the present invention, the musical instrument and/or acoustic apparatus is provided by moulding the entire body part of instrument as being one body with polyurethane foam, therefore, resulting in a period of process shorter than the prior arts which have used woods, and saving the process cost, while maintaining the quality of sounds coming from those musical instrument and/or acoustic apparatus in at least same level as those of the prior art.

#The various kinds of musical instruments, such as electric guitar or piano, has customarily been made of woods which should have been selected through a rigid inspection, and therefore, was expensive. In order to manufacture the electric guitar, especially the body part of electric guitar with wood in the conventional process, the woods should be processed by baking/drying the woods in a drying furnace; sizing the wood into a predetermined size; gluing the woods together into the predetermined shape of electric guitar; and processing the body of electric guitar to provide a pocket with which the required electric devices are equipped, and to have a predetermined curve of outline, which have been complicated and long-term processes.

#Hereinafter, the brief description of drawings attached to the specification is provided:

#FIG. 1 depicts a schematic view of the electric guitar manufactured according to a preferable exercise of the present invention; and

#Each FIG. 2a to FIG. 2f show the results (HZ) from an acoustic test between the strings of guitars of the present invention and prior art, depending on various range of wave lengths of acoustic sound.

#A musical instrument according to the present invention has its entire body portion manufactured by moulding the body with synthetic resin, in which the said musical instrument is an electric guitar which has the entire body 4 consisting of a base plate 1, a neck part 2 connected to the base plate 1, and a head part 3 connected to the end of the said neck part 2 to hang the strings, and in which the said entire body 4 is made of polyurethane foam having specific gravity in the range of 0.3 to 0.9.

#The electric guitar according to the invention may contain additional porous particles selected from a group comprising wood chips, silica or mixtures thereof, which are homogeneously contained in the polyurethane foam which forms the entire body portion of the electric guitar. However, in aspect of the cost of material and the rigidness, talc, plaster, clay, etc. may also be used.

#Total amount of particles to be admixed in the polyurethane foam is preferably 5 to 8% by weight based on total weight of polyurethane foam, and the average diameter of the porous particles ranges preferably from 1 to 50 μm.