EXPANDABLE PLUG AND TOOL FOR PRODUCING AN ENLARGED APERTURE WITHIN A BORE TO TAKE EXPANSION PLUG

摘要

The disclosure relates to a one-piece masonry dowel, pin or peg (10) for fitted implantation in a bore having an internal enlargement (24), a tool (31) for and method of making the enlargement (24), and a tool for implanting the peg in the bore. The peg (10') consists of a sleeve (11) with internal threading (21) for a fastening screw, the leading part (14) of this sleeve having a plurality of thickened segments of a cylinder separated by axial slots, and the outer diameter of the cylinder made up of these segments being variable in such a way that the sleeve can be pushed into a bore and snapped into an enlargement in this bore. The leading part (14) of the sleeve (11) is integrally provided at the end thereof which leads in the push-in direction with an extension (19) which is likewise divided longitudinally into segments and the outer diameter of which in its relaxed condition corresponds to that of the unslotted annular part (12) of the sleeve (11). Internal threading (21) is provided in the zone of the leading part (14) and the extension (19). The tool (31) for forming an enlargement or countersink in the bore has rotatable cutter blades (33) for making the enlargement (24), these being secured at the leading end of the tool to axially immobile and radially resilient arms (32) which can be moved out under axial pressure on a rotary spindle (44) of the tool in such a way that an inner expander element (48) is axially movable between them. The tool for implanting the peg has a leading end formed with steps to carry and insert the sleeve in the bore.