| 摘要 |
<p>Cables for light fittings or electrical appliances can be fixed to a wall by cable clips, entirely made of a plastics such as glass-fibre reinforced polyamide in a one-piece design, which are driven into cylindrical holes in the wall. Expanding part of a wall plug has a cylindrical bore and has four slots at right angles to each other. Before it is driven into the hole up to a flange, its serrated surface has an increasing diameter, inscribed in a cone. The pin is joined by a weak bond to the flange where it penetrates 0.2 mm into the bore. Hammer blows on the head sever it, drive the pin in the bore and urge the serrations against the hole walls. Serrations retain the pin in the bore and the hammer head locates the cable with its V-surfaces.</p> |
