To form a plurality of flow passages in a pipe body such as a rocker shaft at a low cost.
Two groove parts 24 extending over the whole length on an inner circumference surface of the rocker shaft 23 (pipe body) formed out of steel pipe is broached with them faced each other in a radial direction. A spring steel plate 25 (elastic flow passage partition material) having wider dimension (outer dimension) than inner diameter dimension of the rocker shaft 23 is bent in a width direction (direction in which the outer dimension contracts), and is inserted in the rocker shaft 23 with both width end parts engaged with the groove parts 24. The spring steel plate 25 is fixed in the rocker shaft 23 by its own elastic repulsion force to divide the inside of the rocker shaft 23 into two systems of oil supply flow passages 26.
IHARA MIKI
ONO MASAYOSHI
ISHII SHOICHI
KASUYA SEIKO
Seiichi Otsuka