Patent ID: 9222557
Filing Date: 2015-12-29
Classification: F16H,Y10T

Abstract:
1. A dual-screw linear actuator, comprising: an inner push tube; an outer push tube, sheathed on the inner push tube, and axially movable on the inner push tube; a first nut part assembly, directly and fixedly coupled to the outer push tube, and movably screwed to an inner screw, wherein a coupling is fixed to an end of the inner screw away from the first nut part assembly; the first nut part assembly further includes a first screw cover and a socket part covering the first screw cover, the socket part is fixedly coupled to an end of the outer push tube to move along the inner screw, and the first screw cover is screwed to the inner screw; and a second nut part, directly and fixedly coupled to the inner push tube, and movably screwed to an outer screw, and the outer screw being hollow, and the coupling being sleeved into the outer screw and axially movable along the outer screw; thereby, when the outer push tube is inserted into a casing tube and positioned by the casing tube, the outer push tube moves axially along the inner screw without rotating relative to the casing tube; when the inner screw rotates, the outer screw is driven to rotate simultaneously by the coupling fixed to the inner screw, such that the second nut part axially moves along the outer screw without rotating by being positioned by the inner push tube; thus the first nut part assembly and the second nut part on the inner and outer screws move along with the inner and outer push tubes synchronously for an extension or a contraction.