Patent ID: 8684336

Claim:
An improved crown pulley assembly and an improved top drive assembly, said improved crown pulley assembly attached to an upper end of a drilling rig derrick, said drilling rig derrick having a lower end secured to a derrick support base, said drilling rig derrick vertically suspending said improved top drive assembly, said improved drown pulley assembly and improved top drive assembly comprising: said improved crown assembly providing a lower frame member defining a well side and a rig side, a lower portion attached to said upper end of said derrick, and an upper portion rotatably suspending an angled first rig side pulley, an angled second well side pulley, a perpendicular third well side pulley, a central fourth transitional pulley, a perpendicular fifth well side pulley, an angled sixth well side pulley and an angled seventh rig side pulley, with said first rig side pulley and second well side pulley being in alignment, said third well side pulley and said fifth well side pulley being parallel and sharing a common axis, said fourth transitional pulley being perpendicular to said third and fifth well side pulleys and suspended above said lower frame member between said well side pulleys and said rig side pulleys, and said sixth well side pulley and seventh rig side pulley being in alignment; and said improved top drive assembly is slidably engaged with said drilling rig derrick, said improved top drive assembly comprising an upper top drive support member defining a lower portion suspending a top drive member, two lateral side portions each supporting vertical guide tracks which slidably engage guide rails welded upon inner facing surfaces of a pair of parallel well side legs defining a channel within said drilling rig derrick, and an upper portion extending a left side pulley support member and a right side pulley support member, each said pulley support member rotatably suspending a set of paired parallel top drive pulleys which are equidistant from each lateral side portions, each pulley parallel with another and sharing a common axis, each pulley further defining an outer left pulley and an inner left pulley extending upward from said left side support member, and an inner right pulley and an outer right pulley extending upward from said right side support member.