Patent ID: 6843783
Filing Date: 2005-01-18
Classification: A61M

Abstract:
1. An injection needle to be attached to a liquid injection port formed on the distal end of a liquid container that contains insulin solution or dental drug inside, comprising: a puncturing needle part having a puncturing part capable of puncturing a body; a liquid introducing needle part capable of communicating with the inside of said liquid container, said puncturing needle part and said liquid introducing needle part constituting a single needle body, said puncturing needle part having an intermediate part formed between said puncturing part and said liquid introducing needle part and connecting them smoothly by changing its diameter continuously; the puncturing needle part and the liquid introducing needle part being made of metallic material, and a central axis extending from a proximal end of the liquid introducing needle cart to a distal end of the puncturing needle part being straight; and a housing that supports said puncturing needle part and said liquid introducing needle part in such a way as to allow the liquid to flow between the two needle parts, the housing including a bottom wall wherein; at least a portion of said puncturing part having a constant outer diameter in the range of 0.15 mm-0.22 mm, the length of the portion of constant outer diameter being in the range of 0.2 mm-8 mm; said puncturing part has an inner diameter in the range of 0.05 mm-0.15 mm; said intermediate part having a shape tapering thinner toward the distal end and an inner diameter gradually reducing toward the distal end; said puncturing needle part has a length extending from the bottom wall of the housing that is in a range 0.5 mm-10 mm; said liquid introducing needle part has a larger outer diameter than at least the vicinity of the distal end of said puncturing part; said liquid introducing needle part having an inner diameter in the range of 0.25 mm-0.5 mm and an outer diameter in the range of 0.3 mm-0.6 mm; and a cutting edge is formed at the end of said liquid introducing needle part for penetrating through an elastic member that is provided to seal the liquid injection port.