PURPOSE: To feed lubricating oil reliably to the oil passage of the pinion shaft of planetary gear mechanism so as to lubricate a pinion effectively.

CONSTITUTION: A lubricating oil guide member 18 is mounted to the side face of the planetary carrier 61 of planetary gear mechanism P1 so as to lubricate a pinion 81 supported on a pinion shaft 91 fixed to the planetary carrier 61. The lubricating oil guide member 18 is provided with a feed oil pipe 34 connected to the outer end of a feed oil passage 36 extended in a radial direction, and the feed oil pipe 34 is fitted to the oil passage 11 of the pinion shaft 91. Lubricating oil fed through the oil passages 15, 16 of a main shaft 3 and the oil passage 17 of a sun gear 51 is led to the oil passage 11 of the pinion shaft 91 through the feed oil passage 36 and feed oil pipe 34 of the lubricating oil guide member 18 so as to lubricate the pinion 81.