To provide a method of shaping a panel engaging portion, according to which a rib can be completely cut away by a punching die, and the height of the rib is minimized.
According to the method, first a panel 1 having the rib 6 on a rear surface thereof is extruded. The rib 6 has a guide groove 6a formed in a tip surface thereof, a widened portion 6c formed on both sides of the guide groove so as to be wider than an ordinary portion 6b and to have side surfaces almost in parallel with side surfaces of the widened portion 6c, and a diagonal portion 6d formed on both side surfaces of a boundary portion between the widened portion 6c and the ordinary portion 6b. Then the rib 6 is cut away by the punching die except for part thereof, and a screw hole 7 for allowing insertion of a tapping screw 3 therein is formed in the top surface of a remaining portion of the rib 6.
Masayoshi Kanda
Akio Miyao