| 主权项 |
1. A concrete wall anchor, comprising
an elongated hollow body having an axis, an identical transverse cross section over its whole axial length, upper and lower ends provided with upper and lower flat surfaces extending transversely to said axis and parallel to one another, and a central cylindrical opening having an axis coaxial with the axis of the body and extending in an axial direction, a plurality of ribs projecting radially from an outer surface of the body, spaced from one another in a circumferential direction, and extending in a longitudinal direction of said body, wherein each of the ribs narrows radially outwardly to a line by two identically inclined surfaces extending over the whole axial length of the body, wherein said ribs are separated from one another in the circumferential direction by radially outwardly convex arcuate portions of the body each having a circumferential dimension which is multiple times greater than a circumferential dimension of each of the ribs; and a plurality of anchoring legs extending downwardly from said lower end of said body and spaced from one another on the circumferential direction; wherein said cylindrical central opening of said body has a cylindrical upper part which is threaded to receive a threaded lower part of a driving tool constructed to drive the concrete wall anchor in a concrete wall, wherein said central opening has a cylindrical non-threaded remaining part located between said upper threaded part of said central opening and said anchoring legs and constructed for passing a spreading tool into an area of said anchoring legs when the concrete wall anchor is in the concrete wail and spreading said anchoring legs to reliably hold the concrete anchor in the concrete wall, wherein said anchoring legs are constructed so that in a non-spread position they abut centrally against one another at their ends spaced from said body, wherein each of said anchoring legs has a lower part which is spaced from said body and reduces radially outwardly to a point wherein said body has a cross section in a direction perpendicular to said axis, which cross section is identical over the whole axial length of said body from the upper flat surface to the lower flat surface. |
