| 摘要 |
PROBLEM TO BE SOLVED: To provide a gear transmission in which a looseness or noise occurred at a fitting hole between a fitted part of a crank shaft and a transmission gear can be restricted at a low cost.SOLUTION: A gear transmission 1 comprises a crank shaft 10 having a fitted part 10c; gear members 14, 16 having teeth 14a and 16a; a first cylinder 2 having teeth 3 engaged with teeth 14a, 16a of the gear members 14, 16; a second cylinder 4 that can be relatively rotated in respect to the first cylinder 2 through oscillation of the gear members 14, 16 accompanied with rotation of the crank shaft 10; and a transmission gear 20 having a fitting hole 20b to which the fitted part 10c of the crank shaft 10 is fitted. The fitting hole 20b of the transmission gear 20 shows that a shape of section crossing at a right angle in an axial direction of the crank shaft 10 is polygon, and the fitted part 10c of the crank shaft 10 shows that a shape of section crossing at a right angle in an axial direction of the crank shaft 10 is polygon adapted to a sectional shape of the fitted hole 20b.SELECTED DRAWING: Figure 1 |
