Patent ID: 7882853

Claim:
A rotary feed-through for supplying fluid to a rotating machine part comprising: a hollow shaft ( 3 ) that is rotatably supported in a housing ( 1 , 2 ) and has a first sliding surface ( 29 ); a sealing bushing ( 31 ) that is arranged in a rotationally fixed fashion within the housing ( 1 , 2 ) coaxial to the hollow shaft ( 3 ); a second sliding surface ( 30 ) for contacting the first sliding surface ( 29 ); a collecting chamber ( 27 ) that is arranged within the housing ( 1 , 2 ) and configured for collecting leakage fluid escaping between the two sliding surfaces ( 29 , 30 ); a detection channel ( 26 , 33 , 34 , 37 , 39 , 47 ) arranged within the housing ( 1 , 2 ) and connected to the collecting chamber ( 27 ), the detection channel ( 26 , 33 , 34 , 37 , 39 , 47 ) including an inner leakage channel ( 26 , 33 , 34 , 47 ) extending along the hollow shaft ( 3 ) and at least one outer leakage channel ( 37 , 39 ) radially offset relative to the inner leakage channel; and a leakage sensor ( 41 ) connected to the detection channel ( 26 , 33 , 34 , 37 , 39 , 47 ); wherein the outer leakage channel ( 37 , 39 ) is formed by at least one coaxial bore ( 37 ) that extends parallel to the hollow shaft ( 3 ) in a front housing part ( 1 ) and by a receptacle bore ( 39 ) in a rear housing part ( 2 ) of the housing ( 1 , 2 ) that is connected to the axial bore ( 37 ).