Patent ID: 7938607

Claim:
A metal plate member fixation device for fastening to a mounting through hole of a first metal plate member and a screw hole of a second metal plate member to join said first metal plate member and said second metal plate member together, the metal plate member fixation device comprising: a locking device insertable through the mounting through hole of said first metal plate member and fastenable to the screw hole of said second metal plate to lock said first metal plate to said second metal plate, said locking device comprising a cap, said cap having a center opening, and a lock screw bolt axially mounted in said center opening of said cap, said lock screw bolt comprising a head fixedly fastened to said cap at one end of the center opening of said cap, a shank perpendicularly extended from a bottom wall of said head, a thread spirally extending around the periphery of one end of said shank remote from said head and suspending outside said cap and a shoulder connected between the bottom wall of said head and said shank, said shoulder defining a bottom stop wall around one end of said shank remote from said thread; a barrel, said barrel comprising a mounting hole extending through top and bottom sides thereof for the passing of the shank of said lock screw bolt, an annular inside step extending around an inside wall thereof inside the mounting hole near the top side of said barrel and an annular inside locating groove extending around the inside wall inside the mounting hole near the bottom side of said barrel; a spring member received in the center opening of said cap and stopped between the bottom stop wall of the shoulder of said lock screw bolt and the annular inside step of said barrel; and a compressively deformable annular stop member set in said barrel around the shank of said lock screw bolt and forced into the annular inside locating groove of said barrel to secure said lock screw bolt to said barrel for allowing axial movement of said lock screw bolt relative to said barrel and stopping against one end of the thread of said lock screw bolt to prohibit escape of said lock screw bolt of said locking device from said barrel.