COMPRESSED WOOD HANDRAIL AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To secure prescribed flexural strength even when a diameter size is reduced by radially compressing a workpiece manufactured longitudinally in the fiber direction, and keeping the compressed state. SOLUTION: A raw wood W1 is sawn longitudinally in the fiber direction by a sawing machine 1 to form a solid square timber W11 (sawing process P11). The square timber W11 is heated and compressed in the direction perpendicular to the fiber direction to form a compressed square timber W12 (compressing process P12). A dielectric heating process by high frequencies is applied to the compressed square timber W12, and the compressed state is held and fixed to form an elbow raw material W13 (fixing process P13). Corner sections of the elbow raw material W13 are cut by a cutting machine 3 to form a circular cross sectional shape, and an elbow handrail W14 is obtained as a product (machining process P14). The handrail W14 capable of securing the prescribed flexural strength even when its diameter size is reduced to such a level that the handrail W14 can be reliably gripped by a hand can be manufactured through the processes P11-P14.