Plug units, particularly for HPLC, connection system and corresponding use

Abstract

A plug unit configured for use in high performance liquid chromatography is described. The plug unit comprises a capillary comprising a capillary distal face; a sealing element, wherein at least a portion of the sealing element is located distal from the capillary distal face; and a biasing element configured to bias the capillary towards the sealing element.

What is claimed is: 
     
         1 . A plug unit comprising
 a capillary comprising a capillary distal face;   a sealing element, wherein at least a portion of the sealing element is located distal from the capillary distal face;   a biasing element configured to force the capillary against a proximal face of the sealing element; and   a housing assembly, wherein the housing assembly houses the biasing element.   
     
     
         2 . The plug unit of  claim 1 , wherein the plug unit further comprises a thrust piece surrounding a distal end of the capillary, and wherein the capillary is configured to move axially with respected to the thrust piece. 
     
     
         3 . The plug unit of  claim 2 , wherein the sealing element is located at a distal end of the thrust piece. 
     
     
         4 . The plug unit of  claim 2 , wherein the sealing element is fixed to the thrust piece. 
     
     
         5 . The plug unit of  claim 1 , wherein the housing assembly comprises a first housing section and a second housing section. 
     
     
         6 . The plug unit of  claim 5 , wherein the housing assembly comprises a connection mechanism for connecting the plug unit to a socket unit, wherein the connection mechanism is located on the first housing section. 
     
     
         7 . The plug unit of  claim 5 , wherein the second housing section houses the biasing element. 
     
     
         8 . The plug unit of  claim 2 , wherein the thrust piece is configured to move axially with respect to the housing assembly. 
     
     
         9 . The plug unit of  claim 2 , wherein the housing assembly is configured to receive the thrust piece and prevent the thrust piece from falling out of the housing assembly. 
     
     
         10 . The plug unit of  claim 2 , wherein the housing assembly comprises a thrust piece receiving opening, and wherein at least a section of the thrust piece is received in the thrust piece receiving opening. 
     
     
         11 . The plug unit of  claim 10 , wherein the thrust piece further comprises a proximal section with a proximal thrust piece diameter, wherein the proximal section is received in the thrust piece receiving opening, and wherein the thrust piece receiving opening comprises an inner diameter being greater than the proximal thrust piece diameter. 
     
     
         12 . The plug unit of  claim 11 , wherein the thrust piece comprises a distal section with a distal thrust piece diameter wherein the housing assembly further comprises a distal section having an inner diameter being greater than the distal thrust piece diameter and smaller than the proximal thrust piece diameter, wherein preferably, the distal section of the housing assembly is flanged inwardly. 
     
     
         13 . The plug unit of  claim 1 , wherein the plug unit further comprises a thrust transmission element fixed to the capillary and wherein the thrust transmission element is configured to transmit an axial force from the biasing element to the capillary. 
     
     
         14 . The plug unit of  claim 13 , wherein the thrust transmission element comprises a proximal face configured to be subjected by an axial force of the biasing element. 
     
     
         15 . A system comprising:
 a plug unit comprising:
 a capillary comprising a capillary distal face; 
 a sealing element, wherein at least a portion of the sealing element is located distal from the capillary distal face; 
 a biasing element configured to force the capillary against a proximal face of the sealing element; and 
 a housing assembly, wherein the housing assembly houses the biasing element; and 
   a bushing unit configured to receive the plug unit.   
     
     
         16 . The system of  claim 15 , wherein
 when the plug unit is received in the bushing unit, only a distal end of the sealing element contacts the bushing unit.   
     
     
         17 . A method of connecting a pug unit to a bushing unit, in which the plug unit and the bushing unit are configured for use in high performance liquid chromatography,
 the plug unit comprising:
 a capillary comprising a capillary distal face; 
 a sealing element, wherein at least a portion of the sealing element is located distal from the capillary distal face; 
 a biasing element configured to force the capillary against a proximal face of the sealing element; and 
 a housing assembly, wherein the housing assembly houses the biasing element; and 
   the bushing unit configured to receive the plug unit;   wherein the method comprises:
 inserting the plug unit into the bushing unit; 
 contacting the sealing element to a bottom section of the bushing unit; 
 abutting the capillary distal face to the sealing element; and 
 advancing the housing assembly into the bushing unit to cause a compression of the biasing element, and to cause a resulting axial force of the biasing element to force the capillary in the distal direction. 
   
     
     
         18 . The method of  claim 17 , further comprising:
 abutting the proximal face of the thrust piece against a proximal abutment face of the housing assembly to transmit an axial force from the housing assembly to the thrust piece and then to the sealing element.