US Patent 11691857 Two speed trailer jack

A linear jack includes an outer sleeve, an inner sleeve disposed at least partially within the outer sleeve, and an inner screw disposed at least partially within the inner sleeve. The outer sleeve is threadedly coupled to an outer diameter surface of the inner sleeve. The inner screw is threadedly coupled to an inner diameter surface of the inner sleeve. A thread pitch of the outer sleeve is greater than a thread pitch of the inner screw.