Abstract: A method for producing a drill bit includes preparing a metal shank and a metal drill, with the metal shank having a hardness greater than a hardness of the metal drill. Each of the metal shank and a metal drill includes an end having an end face. The metal shank and the metal drill are connected end to end, with the end face of the metal shank coaxially abutting the end face of the metal drill. The ends of the metal shank and the metal drill connected end to end are welded to form a molten pool at the welding area. A surface treatment is conducted on the welding area after welding. The welding area is annealed after the surface treatment.

Abstract: A screwdriver bit includes a shank for coupling with a tool for rotating the shank. An engaging portion extends from one of two ends of the shank and includes an insertion section for coupling with a fastener. A reduced, threaded section is formed between one of the ends of the shank and the insertion section of the engaging portion. The reduced, threaded section includes an outer diameter smaller than that of the ends of the shank and an outer threading. The outer threading of the reduced, threaded section provides uniform stress distribution during torque transmission.

Abstract: A photoluminescent screwdriver includes a handle, a photoluminescent member, and a shank. The handle includes at least one transparent portion and an engaging hole. The photoluminescent member is mounted in the engaging hole of the handle and includes a longitudinal hole. The photoluminescent member further includes an indicia on an outer surface thereof or having a color. The shank includes a rear end engaged in the longitudinal hole of the photoluminescent member.