Patent ID: 6896460

Claim:
A fastener for connecting plate members with mounting holes, comprising: a male member having a main body, a female member to be inserted into the mounting holes in the plate members and including a cylinder body for receiving the main body therein, a projecting portion formed on an outer periphery of the cylinder body at one end thereof and adapted to contact a periphery of one of the mounting holes of the plate members, and protruding portions formed on an inner peripheral portion of the cylinder body at a side away from the projecting portion, a first engaging portion formed on one of an outer surface of the main body and an inner surface of the cylinder body, said first engaging portion having a first engaging screw thread projecting in a direction away from the surface where the first engaging portion is formed, and a second engaging portion formed on the other of the outer surface of the main body and the inner surface of the cylinder body, and having second and third engaging screw threads and a smooth surface portion interposed therebetween, said second and third engaging screw threads projecting in a direction away from the surface where the second and third engaging screw threads are formed so that when the male member is inserted into the female member, the first engaging screw thread engages the second engaging screw thread, passes over the smooth surface without engagement therewith, and engages the third engaging screw thread.