Patent ID: 7717170

Claim:
A well drilling head, comprising: a well drilling head housing having a sidewall structure defining a central bore; a bearing assembly including an outer barrel having a central bore, an inner barrel at least partially disposed within the central bore of the outer barrel and bearing units coupled between said barrels for providing concentric alignment of said barrels and allowing rotation therebetween, wherein the bearing assembly is at least partially disposed within the central bore of the well drilling head housing; a bearing assembly retaining structure coupled between the bearing assembly and the housing for releaseably securing the bearing assembly within the central bore of the well drilling head housing; a canister body including an upper end portion, a lower end portion and a central passage extending therebetween, wherein the central passage of the canister body is configured for having a stripper rubber assembly disposed therein, wherein the upper end portion of the canister body includes a plurality of bayonet connector structures integral therewith within the central passage of the canister body, and wherein the lower end portion of the canister body is fixedly engaged with the inner barrel of the bearing assembly; a canister body lid including an exterior surface, an upper end portion, a lower end portion and a central passage extending between said end portions thereof, wherein the lower end portion thereof is disposed within the central passage of the canister body at the upper end portion of the canister body, wherein the canister body lid includes a plurality of bayonet connector structures on the exterior surface thereof and wherein each one of said canister body lid bayonet connector structures is configured for being selectively and matingly engaged with one of said canister body bayonet connector structures for interlocking the canister body lid and the canister body and wherein the canister body lid is configured in. a manner inhibiting relative rotation between a stripper rubber carrying portion thereof and a bayonet connector structure carrying portion thereof about a longitudinal axis of the central passage; and a stripper rubber assembly fixedly attached to the stripper rubber carrying portion of the canister body lid.