| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to determine in advance the replacement timing for an axle case before the concentration of stresses occurring repeatedly on the axle case breaks it down by cracking.SOLUTION: A crack detection structure for axle cases comprises a first fragile part 1 formed in the edge of the central aperture of an axle case by cracking, penetration or thickness reduction to constitute the first start point of a crack in the axle case; a second fragile part 2 formed in a vicinity position away from the first fragile part 1 by penetration or thickness reduction of the edge to cause the greatest stress on the route linking to the first fragile part 1 to constitute the first crack thereon; and detecting means 3, disposed between the first fragile part 1 and second fragile part 2 to detect any crack occurring between the first fragile part 1 and second fragile part 2. |
