Marine propulsion machine having drive shaft

Abstract

In an outboard motor S, a first drive shaft 31 and a second drive shaft 32 are interlocked by an intermediate gear mechanism 33 including a drive gear 34 mounted on the first drive shaft 31 and a driven gear 35 mounted on the second drive shaft 32. The second drive shaft 32 is supported in an upper bearing 38 and a lower bearing 39 disposed on the upper and the lower side of the driven gear 35. The upper bearing 38 supports an upper end part 32a of the second drive shaft 32 extending upward from the driven gear 35 and the upper bearing 38 is at a vertical position coinciding with that of the drive gear 34. The lower bearing 39 is placed at a position on a lower end part 32b of the second drive shaft 32. The lower end part 32b extends between the driven gear 35 and an input gear 51 included in the output gear mechanism 50. The first drive shaft 31 drives an oil pump 70 for supplying moving parts requiring lubrication and placed in a gear case 13 holding the output gear mechanism 50 interlocked with the second drive shaft 32. The second drive shaft 32 is short and light, the outboard motor can be manufactured at a low manufacturing cost and the oil pump 70 is small.

Dependencies are inferred from the claim text.