Patent ID: 7399283

Claim:
A medical guide wire having a stepwisely thickness-reduced but breadth-increased distal tip structure comprising: a core wire inserted into a helical coil body; a head plug attached to a distal end of said core wire and a distal end of said helical coil body; a core line securement portion in which said core wire is firmly fixed together in one piece to an inner side of said helical coil body so as to form a top leading end portion between said core line securement portion and said head plug; and a flat plane structure having corresponding segment plates in which said core wire of said top leading end portion gradually changes through a plurality of stepped portions that act as transitions between said segment plates within said helical coil body so that the thickness of said core wire is progressively reduced stepwisely while the breadth of said core wire is successively increased stepwisely as approaching a foremost distal end of said top leading end portion, wherein said core wire of said top leading end portion has a core wire portion circular in cross section so that said segment plates of said flat plane structure extend contiguously forward from said core wire portion; the core wire has a constant cross-sectional area throughout the segment plates along a lengthwise direction of said core wire; and a respective thickness of each segment plate of the core wire is constant between adjacent stepped portions along the lengthwise direction of said core wire.