| 摘要 |
The invention relates to a connection device for flat substrates, in particular for PMMA sheets, GRP sheets, plastic sheets or light metal alloy sheets, comprising an annular disk (1) which has on its outer lateral surface (3) a surface structure (4) for anchoring in the flat substrate (17) and through which passes a clamping screw (8) having a screw head (9) and a shank (10) with external thread (11), and a nut (18) which can be screwed onto the external thread (11) for clamping the annular disk (1) axially between the screw head (9) and the nut (18), wherein the annular disk (1) can be widened in the radial direction as a consequence of the clamping between the screw head (9) and the nut (18) in order to clamp the annular disk (1) against the internal circumference (19) of a bore, preferably formed as a blind bore, in which the annular disk (1) can be received, and in so doing anchor the surface structure (4) in the radial direction in the substrate material of the inner circumference (19) of the bore (16). According to the invention, it is provided that the clamping screw (8) has, in the region of its forward shank end oriented away from the screw head (9), in particular on the end face, a drive, preferably in the form of a drive recess, preferably a polygonal or multi-lobed recess. |
