Patent ID: 7637687

Claim:
A tree grille system for covering tree grates, said tree grille system comprising: a) several grille sections, said sections being interconnected by couplings to form a continuous, self-supporting tree grille, the outer edge of which rests on a support bearing; b) said couplings consisting of two fixed coupling parts, which are each configured on two adjoining grille sections and which are arranged at a distance between one another, and a displaceable coupling part, which can be inserted between the two fixed coupling parts and then rotated into a locking position; c) the fixed coupling parts U formed of segment pieces comprising a ramp-type clamping surface; d) at least one part of the ramp-type clamping surface being provided with a flat undulating or dented fluting; e) the displaceable coupling part comprising a discoidal head having two receiving holes for a hook wrench, a bolt-shaped center part and a two-armed cross bar having an upwardly directed extension on each arm, wherein said extensions are adapted to engage the ramp-type clamping surfaces; f) at least one flat tooth provided on the extensions, said tooth being capable of being locked into place in depressions of the fluting; g) an arc-shaped recess, which extends parallel to the plane of the grille sections and an arc-shaped rib, which delimits the recess and likewise extends parallel to the plane of the grille sections, said recess and arc being provided on the underside of the segment pieces, and wherein the ramp-type clamping surface is formed on the outer peripheral side of the rib; h) at least one part of the outer peripheral side of the rib being provided with the flat undulating or dented fluting; i) said tooth, which is capable of being locked into place in the fluting, being configured on the inner side of both the extensions; and j) the system further including inserts, each capable of being inserted into the receiving holes of the displaceable coupling part and thereby filling the receiving hole, engage with a downwardly projecting pin in one of several bores disposed in a circular arc-shaped manner in the respective segment piece of both the fixed coupling parts.