| 摘要 |
The surface of the elastic exercise appliance bears a pattern different, when load is not exerted, from the pattern when stress is applied. In the expansion direction, the pattern applied to its entire length forms a geometric zigzag, corrugated or flat pattern which, in an unexpanded state, has a set angular or lined condition. In the case of expansion with preset force, another pre-set recognizable pattern emerges as load-indicator .
|
