Patent ID: 8240601

Claim:
A coaxial rotary coupling ( 11 ) comprising a hollow inner tube ( 4 ) and an outer tube ( 7 ), the tubes ( 4 ; 7 ) being provided with complementary splines ( 12 ; 13 ) in mutual engagement and extending in a longitudinal direction (X), said coupling ( 11 ) further including longitudinal approach means ( 21 ) for longitudinally approaching the inner and outer tubes ( 4 , 7 ), together with at least one wedge arrangement ( 19 A, 20 A, 31 ) that acts, under the effect of said approach means ( 21 ), to cause the inner and outer tubes ( 4 , 7 ) to pivot ( 23 ) relative to each other in opposite directions so as to compensate for assembly slack ( 24 ), wherein the coupling ( 11 ) comprises: a soleplate ( 16 ) rigidly secured to a base ( 15 ) of one of said tubes that is a driven tube ( 4 ; 7 ), which soleplate projects radially; a peripheral flange ( 17 ) mounted on the other one of said tubes ( 4 ; 7 ) that is a driving tube, said flange ( 17 ) having splines ( 18 ) complementary to the said splines ( 12 ) of the driven tube ( 4 ; 7 ) and in engagement therewith; and dogs, firstly on a bottom face ( 19 ) of the soleplate ( 16 ) and secondly on a top face ( 20 ) of the peripheral flange ( 17 ), each dog ( 19 A, 20 A) possessing at least one transformation ramp ( 31 ) forming a wedge arrangement, while the longitudinal approach means ( 21 ) are distributed within the coupling ( 11 ) and radially spaced apart from said splines ( 12 , 13 , 18 ), such that in the tangential slack take-up position, the splines ( 12 , 13 ) of the driving tube ( 7 ; 4 ) are in engagement with the splines ( 18 ) of the flange ( 17 ) via the flanks thereof, and downstream therefrom the splines ( 13 , 12 ) of the driven tube ( 4 ; 7 ) are in engagement with the splines ( 12 , 13 ) of the driving tube ( 7 ; 4 ) via the flanks thereof.