Patent attributes
An external circulation ball screw includes an elongate shaft having has an outer circumferential surface formed with a helical rolling groove; a nut having a through hole formed therein for receiving extension of the elongate shaft therethrough, the through hole having an inner circumferential surface formed with a rolling channel corresponding to the rolling groove, the rolling groove and the rolling channel collectively defining a loading passage, the nut having an outer surface, which includes, formed therein, two through apertures that are spaced from each other and in communication with the through hole and a cavity in communication with the two through apertures; rolling elements arranged in the loading passage and having a diameter between 0.3-1 mm; and a circulator having a U-shape and is arranged in the cavity and the through apertures and formed with a return passage connected to the loading passage to collectively define a circulation channel.
