Apparatus for introducing liquids and/or elongated elements into a body cavity

Claim 1

Apparatus for introducing liquids and/or elongated elements such as cannulae, mandrins, catheters and the like into a body cavity, comprising: a catheter hub having a substantially cylindrical, longitudinal channel therethrough, said catheter hub defining an elongated orifice portion of said longitudinal channel, a catheter capillary entending with loose fit into the elongated orifice portion of said longitudinal channel, an intermediate section of said longitudinal channel having a diameter greater than said orifice portion of said longitudinal channel, an internal stepped shoulder located where the intermediate section of said longitudinal channel meets the orifice portion of said longitudinal channel, said catheter capillary having a thick head portion situated within said intermediate section, said thick head portion having mutually parallel first and second annular plane faces, said thick head portion having a central opening, the relative distance between said mutually parallel first and second annular plane faces of said thick head portion being less than the length of said elongated orifice portion of said longitudinal channel, said first annular plane face abutting against said internal stepped shoulder, a radial annular collar formed by ultrasonic welding into the wall of the longitudinal channel, said annular collar having two mutually parallel, substantially flat surfaces extending normal to the longitudinal axis of the longitudinal channel, said second annular plane face of said thick head portion abutting against one of said substantially flat surfaces of said annular collar, said annular collar acting against substantially all of said second annular plane face of said thick head portion to axially compress and radially enlarge and clamp said thick head portion in said intermediate section of said longitudinal channel said annular collar defining a central opening adjacent said central opening of said thick head portion and having a diameter substantially equal to said central opening of said thick head portion, whereby a substantially stepless transition between said central opening of said thick head portion and said central opening of said annular collar is provided, and whereby said thick head portion is axially limited by said internal stepped shoulder and one of said substantially flat surfaces of said annular collar.