Patent ID: 7621092

Claim:
A device for locking two building boards connected to one another in a direction perpendicular to a visible side, comprising: a tongue element inserted into a groove provided in a core of a first building board made of wood material or wood material/plastic mixture, the tongue element running parallel to the visible side and comprising a spring made of steel and having a plurality of wave arches and being bent in a sinusoidal manner; a groove provided in a core of a second building board made of wood material or wood material/plastic mixture and running parallel to the visible side, wherein the groove of the first and second building boards are configured such that when the groove of the first and second building boards overlap during a connection of the first and second building boards, by a vertical lowering movement, the first and second building boards are locked in a direction parallel to the visible side; a lower lip having an outer projection projects upwards on a lateral edge of the first building board and projects laterally over the lateral edge; and a recess on an opposite lateral edge facing towards an underside of the second building board, the recess being embodied to correspond to the outer projection.