To prevent a collision of a seal ring 24 against a side face of a ring groove 27.
In a valve timing changing device of an internal combustion engine for changing the valve timing by fluid pressure in a fluid pressure chamber, a rotary body 15 is concentrically disposed on the outer periphery of a shaft body 17, and two fluid pressure passages for supplying an operating fluid to the fluid pressure chamber are respectively connected to annular passages 11B, 12B formed from inner passages of the shaft body 17 between the shaft body 17 and the rotary body 15. The seal ring 24 for partitioning the two annular passages 11B, 12B is interposed between the shaft body 17 and the rotary body 15. The axial dimension 33 of a groove side part 32 on the ring groove side entering the ring groove 27 forming a substantially rectangular cross section is set shorter than an axial dimension 35 of an opposite side part 34 of the groove of an opposite side of the ring groove 27.
IZUMI HIROYUKI
UENO TARO
KOIKE TOMOYUKI
Hiromichi Kobayashi
Tomioka Kiyoshi