| 摘要 |
<p>A metal expansion anchor sleeve is made by forming an elongated flat sheet metal blank so that it has a longitudinal slot extending inwardly from one of its ends and dividing it into two sections which are connected at the other end and which are each provided with a projecting tongue located in the region of the one end. Each tongue is thereupon bent back onto the respective blank section so that its free end moves through more than 180 DEG , the bending being over a radius equal to at least half the thickness of the blank. The blank is then arcuately bent transversely to the elongation of the slot and formed into an externally substantially cylindrical expansion anchor sleeve having an inner longitudinal passage which, due to the presence of the tongues, diverges in direction away from the one end, i.e., converges towards the one end which is the leading end of the sleeve.</p> |
