Patent ID: 8729371
Filing Date: 2014-05-20
Classification: B22F,B33Y,G10D,Y02P

Abstract:
1. A stringed instrument, comprising: a) a resonance box portion being fabricated by an additive fabrication method of sintering synthetic resin powder by light irradiation and being configured in a single layer; and b) a neck portion protruding from said resonance box portion, wherein material constants at a three-dimensional desired area of said resonance box portion are different from material constants at a three-dimensional area adjacent to the desired area step by step or continuously, and the difference between the material constants is due to changing irradiation conditions of light for each area respectively, said neck portion or said resonance box portion or both are constituted by including an outside contour portion fabricated by sintering and a space portion surrounded by the outside contour portion; at least one discharge hole to discharge unsintered synthetic resin powder, which remained inside the space portion is provided at the outside contour portion, and the at least one discharge hole, after the unsintered synthetic resin powder is discharged, maintains an open state or is closed by a closing member.