| 摘要 |
PROBLEM TO BE SOLVED: To supply a proper amount of lubricant to a sliding portion of a roller while preventing lowering of an oil pressure of an engine oil.SOLUTION: In a cam structure 10, a cam lobe 30 is assembled to a hollow cam shaft 20. The cam lobe 30 has a base cam 31 composed of a base circular portion 31a and a valve lift portion 31b, and a roller 32 disposed on a cutout portion 31n formed on a tip portion 31c of the valve lift portion 31b, having a shaft in parallel with a center shaft of a mounting hole 31h, and rotatable to the base cam 31. The cam shaft 20 and the base cam 31 are provided with an oil passage 34 for communicating a hollow internal portion of the cam shaft 20 with the cutout portion 31n, and supplying an oil of the hollow internal portion to a sliding portion of the roller 32. The oil passage 34 has an oil reserving portion 34b opened to an opposite face 31f of the cutout portion 31n opposed to an outer peripheral face of the roller 32, and a throttle portion 34a formed at a hollow internal portion side with respect to the oil reserving portion 34b, and having a flow channel cross-sectional area smaller than the oil reserving portion 34b. |
