| 摘要 |
<p>With a view to being placed about the head (2) on a lifting bolt (2, 3) placed axially in a hemispherical recess (4) in a concrete building element (5), the load-engaging element (1) comprises a body (6) that is symmetrical about a central plane and shaped like a central segment of a sphere, said body (6) having a roughly radially protruding arm (7) for turning the body (6) in the recess (4), said arm (7) having an abutment surface (8) abutting firmly against the surface (9) of the concrete element (5), when the latter is being hoisted. The body (6) comprises an inverted T-shaped slot (10) extending through approximately 180 degrees along the spherical surface of the body and adapted to receive the head (2) of the lifting bolt (2, 3) by means of a cut-out (11), through which the bolt head (2) may be inserted in and removed from the slot (10). A central slot (12) extending approximately diametrically through the body (6) opens into the inverted T-shaped slot (10), and a bolt (14) placed eccentrically about the abutment surface (8) extends across the central slot (12) and is secured in bores in the body (6). The end link (17) of a connecting means in the form of a chain (16) is placed in the central slot (12) and retained by the bolt (14). When the concrete element (5) is being lifted, the pull in the chain (16) will exert a turning moment on the body (6), causing the abutment surface (8) on the arm (7) to be pressed against the surface (9) of the concrete element (5), so that the body (6) cannot inadvertently be turned to the position, in which the cut-out (11) is positioned about the head (2) of the lifting bolt (2, 3), allowing the latter to be released from the load-engaging device (1).</p> |
