Patent ID: 9587440
Date: 2017-03-07
CPC Classifications: E21B

Claim:
1. A dynamic point-the-bit rotary steerable drilling tool, comprising a rotary housing ( 19 ), a stabilized platform assembly ( 37 ), a hollow servo-motor assembly ( 16 ), a drilling fluid passage ( 18 ), an inner eccentric ring ( 31 ), an outer eccentric ring ( 7 ), a drilling bit shaft ( 5 ) and a universal joint ( 38 ); wherein the stabilized platform assembly ( 37 ) comprises a stabilized platform body ( 10 ) mounted in the rotary housing ( 19 ) and a stabilized platform upper-end cover ( 12 ) connected with the stabilized platform body; wherein a stabilized platform upper-bearing ( 11 ) is fixed between the stabilized platform body ( 10 ) and the stabilized platform upper-end cover ( 12 ); wherein an upper end of the stabilized platform upper-end cover ( 12 ) is connected with a gear box of the hollow servo-motor assembly ( 16 ) through a coupler ( 15 ), and a lower end of the stabilized platform body ( 10 ) is connected with the outer eccentric ring ( 7 ); wherein said dynamic point-the bit rotary steerable drilling tool further comprises a stabilized platform communication and power supply system; wherein said stabilized platform communication and power supply system incorporates an instrument storehouse ( 20 ) fixed at an upper end of the rotary housing ( 19 ), a main circuit board ( 24 ), an auxiliary circuit board ( 27 ) mounted on the stabilized platform upper-end cover ( 12 ), an electromagnetic coupler primary-side ( 26 ), an electromagnetic coupler secondary winding( 13 ) and an electromagnetic coupler primary-side mounting plate ( 14 ) fixed at a lower end of the coupler ( 15 ); wherein the main circuit board ( 24 ) is mounted on the electromagnetic coupler primary-side mounting plate ( 14 ); wherein the electromagnetic coupler secondary winding ( 13 ) is connected with the auxiliary circuit board ( 27 ), and the auxiliary circuit board ( 27 ) is connected with an attitude sensor ( 30 ) mounted on a side wall of an upper end of the stabilized platform body ( 10 ); wherein the electromagnetic coupler primary-side ( 26 ) is mounted relative to the electromagnetic coupler secondary winding( 13 ) with an air layer reserved therebetween; wherein the electromagnetic coupler primary-side ( 26 ) is static relative to the rotary housing ( 19 ), and the electromagnetic coupler secondary winding( 13 ) is static relative to the stabilized platform body ( 10 ).