Plastic Dowel for Fastening of a Rail and Combination of such a Plastic Dowel and a Rail Screw

A plastic dowel for the fastening of a rail to a solid substrate, with a dowel opening (3) formed at an end face of the plastic dowel (1) for insertion of a rail screw (2) into the plastic dowel (1), with a dowel interior space (8) enclosed by the plastic dowel (1), with a shank section (4) which connects to the dowel opening (3) as viewed in the longitudinal direction (LR) of the plastic dowel (1), and with a holding section (5) which connects to the shank section (4) as viewed in the longitudinal direction (LR) of the plastic dowel and which has an internal thread (21) on its inner side, characterised in that the flank (22) of the internal thread (21), said flank (22) being assigned to the dowel opening (3), is orientated at an angle (β2) of 90°±3° in relation to the longitudinal axis (L) of the plastic dowel (1).

The plastic dowel according to any one of the preceding claims, characterised in that the inner circumferential face or outer circumferential face (10) of the shank section (4) is smooth.

The plastic dowel according to any one of the preceding claims, characterised in that a second holding section (6) connects to the first holding section (5) as viewed in the longitudinal direction (LR) of the plastic dowel (1), in said second holding section (6) also at least one radially outwardly protruding projection (11) is formed or the respective internal thread (21) is continued, and in that the flank of the projection (11) or of the internal thread (21) in the second holding section (6), said flank being assigned to the dowel opening (3), is arranged at an angle of more than 93° in relation to the longitudinal axis (L) of the plastic dowel (1) or is rounded.

The plastic dowel according to any one of the preceding claims, characterised in that the upper flank (12) in the first holding section (5), said upper flank (12) being assigned to the dowel opening (3), is orientated in each case at an angle of 90°±1° in relation to the longitudinal axis (L) of the plastic dowel (1).

The plastic dowel according to any one of the preceding claims, characterised in that the transition from the flank (12) of the projection (11) or of the internal thread (21), said flank (12) being assigned to the dowel opening (3), to the respectively assigned circumferential face (10,23) of the plastic dowel (1), said circumferential face (10,23) being orientated in the longitudinal direction (LR) of the plastic dowel, has a rounded form.

The plastic dowel according to any one of the preceding claims, characterised in that the lower flank (16,26) of the projection (11) or of the internal thread (21), said lower flank (16,26) being assigned to the dowel tip (7), has a convex domed form.

The plastic dowel according to any one of the preceding claims, characterised in that, as viewed in the longitudinal direction, the transition from the upper flank (12,22) of the projection (11) or of the internal thread (21) of the second holding section (6), said upper flank (12,22) being assigned to the dowel opening (3), to the flank (16,26) of the associated projection (11) or of the internal thread (21), said flank (16,26) being assigned to the dowel tip (7), is rounded in a convex domed, continuous curve.

The plastic dowel according to any one of the preceding claims, characterised in that on the outer side of the plastic dowel (1) in the area of the first holding section (5) at least one web (17,18) connected to the shank section (4) and extending in the longitudinal direction (LR) of the plastic dowel (1) is formed,

The width of said web in its base area being equal to at least a fifteenth of the circumference of the plastic dowel (1),

Said web crossing the projection (11) of the first holding section (5) and

The apex face (19) of said web, viewed in the radial direction (R), extending at most to the imagined prolongation of the envelope (U) of the shank section (4).

The plastic dowel according to any one of the preceding claims, characterised in that in the area of the first holding section (5) a groove-shaped recess (27) extending in the longitudinal direction (LR) of the plastic dowel (1) is formed in the inner circumferential face assigned to the dowel interior space (8).

A combination of a rail screw (2) and a plastic dowel (1) formed according to any one of the preceding claims, wherein the rail screw (2) has a screw head (30) and a threaded shank following the screw head (2) in the longitudinal direction (LR) of the rail screw (2), a circulating screw thread (33) being formed on said screw shank, characterised in that the upper flank (38) of the screw thread (33), said flank (38) being assigned to the screw head (30), is orientated at an angle (β3) of 90°±3° in relation to the longitudinal axis (LS) of the rail screw (2).