Threaded connection

Abstract

The invention relates to a threaded bushing on an elongated body for a threaded connection with a threaded plug, wherein the threaded bushing has a conical internal thread, in which adjacent flanks of the internal thread are designed as sections of two identical ellipses offset from one another.

1 . A threaded bushing ( 2 ) on an elongated body ( 1 ) for a threaded connection with a threaded plug ( 4 ), wherein the threaded bushing ( 2 ) has a conical internal thread ( 3 ), in which adjacent flanks of the internal thread ( 3 ) are designed as sections of two identical ellipses (E 1 , E 2 ) offset from one another. 
     
     
         2 . The threaded bushing ( 2 ) according to  claim 1 , wherein the two ellipses (E 1 , E 2 ) are standing ellipses. 
     
     
         3 . The threaded bushing ( 2 ) according to  claim 1 , wherein a center axis of at least one of the two ellipses is arranged at an angle of 70° to 110°, preferably 80° to 100°, to the longitudinal axis of the elongated body. 
     
     
         4 . The threaded bushing ( 2 ) according to  claim 1 , wherein the thread base (GG) between the adjacent flanks is designed as an envelope of the two ellipses (E 1 , E 2 ). 
     
     
         5 . The threaded bushing ( 2 ) according to  claim 1 , wherein the offset (VS) includes at least one translational displacement in the direction of the longitudinal axis (L) of the threaded bushing ( 2 ), the extent of which is between ⅙ and ⅛ of the thread height (GH). 
     
     
         6 . The threaded bushing ( 2 ) according to  claim 1 , wherein the offset (VS) includes at least one translational displacement in the direction of the longitudinal axis (L) of the threaded bushing ( 2 ), the extent of which is between 1/37 and 1/27 of the distance between two adjacent thread bases (GG). 
     
     
         7 . The threaded bushing ( 2 ) according to  claim 1 , wherein the offset (VS) includes at least one translational displacement in the direction of the longitudinal axis (L) of the threaded bushing ( 2 ), the extent of which is between 1/10 and 2/10 of the quotient of the major axis and minor axis of the identical ellipses (E 1 , E 2 ). 
     
     
         8 . The threaded bushing ( 2 ) according to  claim 1 , wherein the offset (VS) of the two ellipses (E 1 , E 2 ) is a pure translation in the direction of the longitudinal axis (L) of the threaded bushing. 
     
     
         9 . The threaded bushing ( 2 ) according to  claim 1 , wherein the elongated body ( 1 ) is a rod section of a drill string for an earth drilling device or a drive element for a rod section of a drill string of an earth drilling device. 
     
     
         10 . A use of a threaded bushing ( 2 ) on an elongated body ( 1 ) for a threaded connection with a threaded plug ( 4 ), wherein the threaded plug ( 4 ) has an external thread ( 5 ) applied to a core, in which adjacent flanks of a thread of the threaded plug ( 4 ) form sections of the same ellipse (E 3 ), wherein a thread is used as the internal thread ( 3 ) of the threaded bushing ( 2 ), in which thread adjacent flanks of the internal thread ( 3 ) are designed as sections of two identical ellipses (E 1 , E 2 ) offset from one another. 
     
     
         11 . A use of a threaded bushing ( 4 ) on an elongated body ( 1 ) for a threaded connection with a threaded bushing ( 2 ), wherein the threaded bushing ( 2 ) has an internal thread ( 3 ), in which adjacent flanks of the internal thread ( 3 ) are designed as sections of two identical ellipses (E 1 , E 2 ) offset from one another, wherein the threaded plug ( 4 ) has an external thread ( 5 ) applied to a core, in which thread adjacent flanks of a thread of the threaded plug ( 4 ) form sections of the same ellipse (E 3 ). 
     
     
         12 . The use according to  claim 10 , wherein the elongated body ( 1 ) is a rod section of a drill string for an earth drilling device or a drive element for a rod section of a drill string of an earth drilling device. 
     
     
         13 . A threaded connection comprising a threaded bushing ( 2 ) according to  claim 1  and a threaded plug ( 4 ) on an elongated body ( 1 ), wherein the threaded plug ( 4 ) has an external thread ( 5 ) applied to a core, in which thread adjacent flanks of a thread of the threaded plug ( 4 ) form sections of the same ellipse (E 3 ). 
     
     
         14 . The threaded connection according to  claim 12 , wherein the ellipse (E 3 ) is identical to the two ellipses (E 1 , E 2 ) of the threaded bushing ( 2 ). 
     
     
         15 . The threaded connection according to  claim 12 , wherein the thread base (GG) also forms a section of the ellipse (E 3 ).