US Patent 9670954 Ball joint member with permanent lubrication

A ball joint member including an inner ring, with a general axisymmetrical shape around a first axis, including an external contact surface having a truncated spherical shape, the inner ring including a coating which bears the external contact surface and an outer ring, of a general axisymmetrical shape around a second axis, including an internal contact surface mating the external contact surface, cooperating with the external contact surface, the outer ring including a coating which bears the internal contact surface, wherein at least one of the inner and outer rings includes lubricant reservoirs made on the coating of one of the external and internal contact surfaces, and wherein the coating of the contact surface of one of the rings is textured with micro-cavities forming the lubricant reservoirs.