| 摘要 |
PROBLEM TO BE SOLVED: To prevent reduction in the strength of a guide base formed of a synthetic resin by reducing heat conduction from a roller shaft which supports a chain guide roller in a freely rotatable manner to the guide base which supports the roller shaft in a freely rotatable manner.SOLUTION: In a pair of opposing side plate parts 22 of a guide base 21 which is disposed oppositely in one side of a torque transmission timing chain 5, a plurality of shaft engaging parts 25 are provided and a shaft end of a roller shaft 31 is supported by each of the shaft engaging parts 25. A chain guide roller 41 is supported in the freely rotatable manner by each of the plurality of roller shafts 31. An area of contact between the shaft end face of the roller shaft 31 and a wall surface 26 of the shaft engaging part 25 is made equal to or smaller than a sectional area of the roller shaft 31 at an axial center. Heat conduction from the roller shaft 31 to the guide base 21 is thereby reduced and reduction in strength caused by a rise in the temperature of the guide base 21 formed of a synthetic resin is prevented. |
