Patent ID: 8806972

Claim:
A linear actuator, comprising: a lead screw; a telescoping rod comprising a hollow cylindrical body threadedly engaged with the lead screw for generating a telescoping action in a linear direction with respect to the lead screw so that another assembly connected to the telescoping rod performs pushing and pulling actions, a distal end of the telescoping rod comprising an accommodating passage penetrating opposing sides of the hollow cylindrical body and forming diametrically opposing openings in the cylindrical body; a plurality of sleeves, each of which comprises a hollow pipe body sized to be frictionally fit in the accommodating passage by engaging two ends of the sleeve with the diametrically opposing openings, respectively, and each sleeve having a different inner radius for receiving a different diameter connecting element; and a detachable cylindrical connecting cap, which is friction fitted onto a top of the telescoping rod at a position with a cap top directly sitting on the distal end of the telescoping rod, where the accommodating passage and the sleeve are just covered by the connecting cap for holding the sleeve friction fitted in the accommodating passage, the connecting cap comprising two diametrically opposing projecting seats each extending from the periphery of the connecting cap to define a planar surface which circumferentially encloses a respective one of the diametrically opposing openings in the telescoping rod and extends to an open lower end of the connecting cap, and a through hole being formed in each of the two planar surfaces of the two projecting seats corresponding to the positions of the two openings, respectively, thereby, in cooperation with the connecting cap, the plurality of sleeves with different inner radiuses are provided to be individually assembled in the telescoping rod, which facilitates exchange of the sleeves for receiving different diameter connecting elements therein, wherein an inner radius of one of the plurality of the sleeves is substantially equal to the radius of the two through holes in the connecting cap, and wherein an inner radius of another of the plurality of the sleeves is substantially smaller than the radius of the two through holes.