Face-Sealing Fluidic Connection System

Abstract

A tubing or fitting assembly has an inner tube layer, an outer tube layer, a sleeve, a tip portion, and can have a nut. Each of the nut, sleeve, inner and outer tubing layers, and tip portion have a passageway therethrough, with at least the passageways in the sleeve, tip portion, outer tube layer, and nut adapted to allow the inner tube layer to pass therethrough or extend over the inner layer. The tip portion can be molded over an end portion of the inner tube layer and also over a portion of the sleeve. The sleeve may include a retention feature in the form of a lip which extends into the tip portion, and also a narrower portion so that the tip portion and sleeve remain coupled together. The inner and outer tubing layers can also be retained by an interference fit. The ends of the tip portion and inner layer together define a substantially flat surface which can form a seal in a flat-bottomed port of a component such as may be found in any one of a number of components in an analytical instrument system, including for example a liquid chromatography system. The nut, tube, ferrule, and transfer tube or liner tube may comprise biocompatible materials. In addition, the nut may have a slot, such as a slot adapted to allow the tube and the nut to be easily and quickly separated or to allow a portion of the tube to be easily and quickly inserted in the nut.

What is claimed is: 
     
         1 . A fitting assembly for a flat-bottomed port comprising:
 a tube comprising an inner tube and an outer tube, wherein the inner tube has a fluid pathway therethrough, and wherein the tube is adapted to fit in a first passageway extending through a nut having a first end and a second end, wherein the tube has a first end and a second end, and wherein at least one of the first end and second end of said tube has a tube seal face end adapted to form a seal in a flat-bottomed port;   a cylindrical transfer tube having a second passageway therethrough, wherein at least a portion of the tube is located within the second passageway of the transfer tube and is secured relative to the transfer tube;   a tip adjacent to and in contact with the tube face seal end, wherein at least a portion of one end of the tip is adapted to form a seal in the flat-bottomed port adapted to engage with a portion of the nut, and wherein a portion of the tip is located between the tube and the transfer tube, and wherein an end portion of the transfer tube abuts an end portion of the tip and is adapted to apply an axial load to the end portion of the tip when the nut is engaged in the port.   
     
     
         2 . The fitting assembly according to  claim 1 , wherein said tip comprises a compressible material and wherein at least one of said transfer tube and an inside surface of said tip are adapted to provide an interference fit with said tube. 
     
     
         3 . The fitting assembly according to  claim 1 , wherein said tube comprises metal, said transfer tube comprises metal, and further wherein said transfer tube comprises a pocket portion at a terminal end thereof, and wherein a portion of said tip is adapted to be held in the pocket portion, thereby providing an interference seal with a portion of said tube. 
     
     
         4 . The fitting assembly according to  claim 1  wherein said tube and said tip each comprise a biocompatible material. 
     
     
         5 . The fitting assembly according to  claim 1  wherein at least one of said tube and said tip comprises at least one of the following: polyetheretherketone (PEEK), polyaryletherketone (PAEK), polyetherketoneketone (PEKK), fluorinated ethylene propylene (FEP), ethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), perfluoroalkoxy (PFA, also called perfluoroalkoxyethylene), polychlorotrifluoroethylene (PCTFE), polymer-sheathed fused silica (such as PEEKSil), fused silica, or silica borite. 
     
     
         6 . The fitting assembly according to  claim 1  wherein at least one of said tube, said transfer tube, and said tip comprise a material which further comprises a filler. 
     
     
         7 . The fitting assembly according to  claim 6  wherein the filler comprises fibers. 
     
     
         8 . The fitting assembly according to  claim 7  wherein the filler comprises at least one of carbon fibers, nanofibers, or metallic fibers. 
     
     
         9 . The fitting assembly according to  claim 1  wherein each of the second end of said tube and the end of said tip have a substantially flat face adapted to provide a seal when pressed against the bottom of a flat-bottomed port. 
     
     
         10 . A fitting assembly for a flat-bottomed port comprising:
 a tube comprising an inner tube and an outer tube, wherein the inner tube has a fluid pathway therethrough, wherein the tube is adapted to fit in a first passageway extending through a nut having a first end and a second end, wherein said tube has a first end and a second end;   a cylindrical transfer tube having a second passageway therethrough, wherein at least a portion of the tube is located within the second passageway of the transfer tube and is secured relative to the transfer tube;   a tip having a third passageway therethrough and providing an interior portion, wherein the tip is adjacent to and in contact with one of the first end and the second end of the tube, wherein the tip is adapted to receive and hold a portion of one of the first end and the second end of the tube in the interior portion, wherein at least a portion of one end of the tip is adapted to form a seal in a flat-bottomed port, and wherein a portion of the tip is located between a portion of the tube and a portion of the transfer tube, and an end portion of the transfer tube abuts an end portion of the tip and is adapted to supply an axially load thereto.   
     
     
         11 . The fitting assembly according to  claim 10 , wherein at least one of said transfer tube and a surface of said tip are adapted to provide an interference fit with said tube. 
     
     
         12 . The fitting assembly according to  claim 10 , wherein said transfer tube has a shorter length than said tube and wherein a portion of said transfer tube is adapted to impinge on a portion of said tip. 
     
     
         13 . The fitting assembly according to  claim 10 , wherein the tip comprises a metal. 
     
     
         14 . The fitting assembly according to  claim 10 , wherein the seal is sufficient to withstand fluidic pressures in the fluid pathway of at least 10,000 psi. 
     
     
         15 . The fitting assembly according to  claim 10 , wherein the seal is sufficient to withstand fluidic pressures in the fluid pathway of at least 15,000 psi. 
     
     
         16 . The fitting assembly according to  claim 10 , wherein the seal is sufficient to withstand fluidic pressures in the fluid pathway of at least 20,000 psi.