| 摘要 |
<p>A twin-blade assembly is formed from two blade steel members (A, B) shaped to have rear mounting legs (3A/B), spring arms (9A, 9B) at opposite ends of the unit, downturned legs (2A, 2B) for reinforcing the members and sharpened blade edges (1A, 1B) on blade strips or margins (5A, 5B). The spring arms can flex to permit relative displacement of the strips (5A, 5B). The assembly may also incorporate a lubricating strip (M), the whole unit and strip being discardable and replaceable as a unit .</p> |
