| 摘要 |
The shank (41, Fig 1), (61, Fig 3) of a screw (4), (6), which is free of a drill bit portion and which is adapted for use with a fibrous board (5), (7), is formed with a screw thread (42), (64) throughout its length, and with a flute (45), (63) which extends from a tip of the shank (41), (61) at a non-parallel angle to the longitudinal axis (44), (62) of the shank (41), (61) |
