| 摘要 |
<p>The invention relates to a screw device 1 for fixing insulating panels together. The screw 1 is made in one piece from synthetic material and comprises a head 2 and a shank 3. The head 2 comprises a flat surface 4 for abutment on one of the said insulating panels, a surface 5 opposite the abutment surface 4, provided with at least one drive wing 6. The wing 6 extends to a selected distance A from the opposite surface 5, said distance A being more than 10 mm. The shank 3 comprises an elongate body 7 extending from the head 2 and substantially perpendicular to the abutment surface 4. The screw 1 comprises a point 8 arranged at an end of the body 7 opposite the head 2, and at least one helical thread 9. The helical thread 9 extends at least over part of at least one of the point 8 and the body 7, and is spaced from the head 2. The helical thread 9 has a diameter H that increases towards the head 2, the helical thread 9 comprising a portion having a frustum-shaped envelope 18, the pitch P of the helical thread 9 being greater than 8 mm.</p> |
