| 摘要 |
A power returnable tape rule has an improved connection between the inner end of the power spring and the hub. The hub has an axially elongated passage therethrough with shoulders at the axial ends thereof which seat in notches formed in the edges of the spring extending therethrough. These shoulders are located intermediate the transverse dimension of the passage and are inclined upwardly towards the axial ends. Bosses on the opposing wall of the passage limit the clearance in the passage and thereby the opportunity for the spring to be lifted from the shoulders.
|
