Patent ID: 6149340
Filing Date: 2000-11-21
Classification: E01F

Abstract:
Apparatus for automatically righting a signpost which had been subjected to a temporary tipping moment comprising:a polygonal tray having a top and a bottom, the tray being positioned over a cavity in the ground and having a hole through the tray's center for providing access to the cavity, the top of the tray having upturned peripheral edges;means for securing the tray to the ground;a compression spring located in the cavity below the tray, said spring having top and bottom ends, the top end bearing against the bottom of the tray;a polygonal plate sized to fit within the tray's peripheral edges, the plate having sides complementary to the polygonal shape of the tray;adaptive means for connecting the signpost to the plate;an elongate, laterally flexible tension member extending from the plate, through the tray's hole and bearing against the bottom end of the spring so that in a first position, the polygonal plate is forcibly restrained within the tray to hold the signpost upright, and in a second position, when a moment is applied to the signpost, a polygonal side of the plate engages the complementary polygonal upturned edge of the tray causing the plate to rotate, displacing a portion of the tension member through the hole and compressing the spring, the compressed spring urging the signpost to right itself again to the first position, the complementary polygonal shape of the tray and plate acting to prevent axial rotation of the signpost and thereby ensure consistent signpost orientation.