Patent ID: 7247148

Claim:
A protector displaceable between a first position in which said protector can move relatively along a longitudinal direction of a needle body having a sharp needle tip at a tip end and a second position in which the relative movement of said protector along the longitudinal direction of said needle body is prohibited in a state where said protector covers the needle tip of said needle body, said protector comprising a main body portion formed by deforming a plate-like member having an elasticity, said main body portion comprising: a first area formed in a center thereof, in which a first hole through which said needle body can penetrate is formed; a second area formed on a needle root side thereof, in which a second hole through which said needle body can penetrate is formed; a third area formed on the needle tip side thereof, in which a penetration portion through which said needle body can penetrate is formed; and a rear connection portion connecting respective end portions of said first area and said second area with each other and a front connection portion connecting respective end portions of said first area and said third area with each other, said main body portion thus having a substantially S shape as a whole a connection portion between said first area and said rear connection portion is urged in such a direction as to make an angle formed between said first area and said rear connection portion become smaller; in said first position, said needle body penetrates through said first hole, said second hole, and said penetration portion; and by moving said protector in a tip end direction relative to said needle body to release an engagement between said penetration portion and said needle body, the angle formed between said first area and said rear connection portion becomes smaller to cause said protector to be elastically deformed into said second position such that an inclination angle of said first area relative to said needle body becomes smaller than the inclination angle in said first position, so that a frictional force is generated or increased between an inner surface of said first hole and an outer peripheral surface of said needle body to thereby prohibit the relative movement of said protector along the longitudinal direction of said needle body.