| 摘要 |
<p>A composite cutting screw die includes screw blade bodies (1) and a shell (2). A plurality of screw blade bodies (1) are connected or integrated with the shell (2). The screw blade bodies (1) have any one of the following features or any of the combinations of the following features: 1. for each of the screw blade bodies (1), the included angle formed by the cutting edge surface (9) at and near a chamfer and the tangent of a concentric circle is larger than the included angle formed by the rear cutting edge surface (9) and the tangent of the concentric circle; 2. the diameter of the screw bottom (7) at the chamfer is less than that of the remaining screw bottoms (4); 3. the cutting edge surface (9) of each of the screw blade bodies (1) is provided with a radiation board (5). The cutting screw die with the above mentioned features can increase the using strength and radiation function, and improve the productivity and the cutting stability.</p> |
