US Patent 8925221 Retainer systems for ground engaging tools

Disclosed are various exemplary embodiments of a lock for a ground engaging tool. The lock may include a head portion and a C-shaped portion extending from the head portion. The C-shaped portion may define a lock slot between two circumferential ends for receiving a portion of a support member to be locked with the ground engaging tool. The C-shaped portion may further include an outer surface configured to be rotatably received in an inner surface of a retainer bushing, an inner surface configured to contact the portion of the support member, and a base extending between the outer surface and the inner surface. The base may include a helical surface with a depth increasing from a first end to a second end.