| 摘要 |
<p>A medical anesthetic needle which comprises an outside needle (2) and a mandrin (3) inserted into the outer needle to freely move in and out, and is slightly bent upward at its tip when its needle axis is positioned horizontal. The mandrin (3) is manufactured by a first step of cutting the tip end of a metallic wire (W) such as stainless steel wires obliquely to form a blade surface (5) which intersects the axis at a predetermined angle of the mandrin blade surface, a second step of cutting off that portion of the metallic wire, which extends from the underside of the wire up to a horizontal plane (M) located at a higher level than the center line of the wire, in a columnar region between the upper end (A) of the blade surface (5) and a position (B) rearwardly distant three times the diameter of the wire or more from the upper end, to form a blade tip (11), a split-columnar connection (10) succeeding the blade tip, and a columnar portion (12) succeeding the connection, and a third step of bending the connection (10) in such a manner that the upper end (A) of the blade surface (5) becomes higher a predetermined distance (h) than the upper surface of the columnar portion (12) and the axis of the blade tip (11) is inclined at a predetermined angle (&thetas;) relative to the horizontal, and cutting the entire length of the mandrin into a predetermined length (L). <IMAGE></p> |
