| 摘要 |
<p>1505795 Expansion rock bolt GD-ANKER GEBIRGS-DUBEL-ANKER GmbH & CO KG 25 June 1976 [26 June 1975] 26649/76 Heading F2H An expansion rock bolt comprising a rod 1 having an expander head 3 and expansible segmented shell 9 provided with teeth 14 arranged above recesses 15 is characterized in that each tooth consists of two sections which form an obtuse angle on their outer surface, and the side walls of each tooth do not contact the shell.</p> |
