Structure of wall mounting junction box

Claim 1

A junction box comprising: a casing having two recessed portions on the topmost edge around a top opening thereof at two opposite locations, a plurality of first through holes and a plurality of second through holes on an upright peripheral wall thereof respectively disposed below said recessed portions, a plurality of horizontal flanges spaced by gaps around said upright peripheral wall on the inside; two mounting tabs respectively made of stainless steel through a punching process, each mounting tab comprising a horizontal projection inserted into either recessed portion and projecting into the holding space of said casing, said horizontal projection having a through hole for inserting a screw in fastening an electric device within said casing, pairs of horizontal pins respectively fitted into said first through holes or said second through holes, and a horizontal wing disposed outside said casing; a cover board made of a rigid plate fitted into the top opening of said casing and supported above said horizontal flanges and over covered the horizontal projection of each metal mounting tab, said cover board having two bottom pins respectively fitted into the through hole on the horizontal projection of either metal mounting tab, and a plurality of bottom ribs respectively inserted into the gaps in said horizontal flanges.