To provide a perforated floor board which prevents the generation of excessive tensile force in the edge part of the notch generated on the boundary between a mesh part and a flat plate part and maintains the fine appearance of a product without leaving bruises of an upper blade in the flat plate part, a method of manufacturing it, a scaffolding board and a work scaffolding stand using the perforated floor board.
This manufacturing method has a cutting and stretching stage where a metallic plate 1 is fed forward by the width of the strand part 11 of a mesh part 13 formed on the metallic plate 1 at a time and the strand part 11 having a half of a short mesh size is formed by cutting a slit on the metallic plate 1 by moving either a lower die 2 or an upper die 4 by one stroke. In the cutting and stretching stage, the metallic plate 1 is alternately shifted to the right and left by a half of the long mesh size each time synchronously with the operation of feeding the metallic plate 1 and a position where the metallic plate is fed by the width of the strand part 11 of the mesh part from the position of the slit in a first cutting and stretching stage is taken as the starting position of the second cutting and stretching stage after reversing the front and the rear in the advancing direction and the upper surface and the back surface of the metallic plate 1 to which the first cutting and stretching stage is performed.
EDA HIROSHI
NAGUMO TAKASHI