| 摘要 |
PCT No. PCT/FR91/00645 Sec. 371 Date Feb. 24, 1993 Sec. 102(e) Date Feb. 24, 1993 PCT Filed Aug. 2, 1991 PCT Pub. No. WO92/02396 PCT Pub. Date Feb. 2, 1992.A trolley has a chassis provided with a load-carrying assembly and a drive unit for imparting a longitudinal translational motion to the trolley. A centering finger has the shape of a polygonal cross-section, vertical-axis pyramid having downwardly-converging edges. The centering finger is supported by an element that rotatably fastens the centering finger to the chassis. The centering finger is connected to a device that can move the finger between a retracted position that is above the floor and an extended position where the finger engages a matching recess housed in a ring, which is, in turn, set into the floor. The recess is positioned in such a way that the vertical axis of the recess passes through the intersection between the longitudinal and transverse axes of a reference point and a theoretical path of the trolley, and at least one of the sides of the recess is perpendicular to the theoretical path. |
