Unit joint for connecting two angularly arranged panel units

In combination:

• two panel units arranged at an angle with respect to each other, each panel unit having a relatively narrow edge surface and a wall surface projecting beyond said edge surface towards the other unit, each edge surface comprising at least one rib having an angle guide surface abutting the angle guide surface on a corresponding rib on the other panel unit so as to define a mutualangle at which said panel units abut, a plurality of coupling projections at said edge surfaces of each panel unit and at the wall surface of each panel unit, said projections having apertures substantially coaxially arranged, said projections on one unit projecting between the projections on the other panel unit, and a common locking rod extending through said apertures, each coupling projection being substantially rectangular and firmly connected to the narrow edge surface and wall surface of the respective panel unit, and substantially filling up the cross section of a channel defined by the narrow edge surfaces and wall surfaces when the angle guide surfaces on both panel units abut each other, each coupling projection having integrally connected thereto an auxiliary rib provided with an inclined auxiliary angle guide surface cooperating with a corresponding inclined auxiliary angle guide surface on a corresponding auxiliary rib on the other panel unit.