Lifting device having parallel double screw rods

A lifting device having parallel double screw rods, comprising:

• a driving means;
• a first transmission means comprising a first screw rod driven by the driving means and a first telescopic tube assembly threadedly connected to the first screw rod and linearly movable relative to the first screw rod, a distal end of the first telescopic tube assembly fixedly connected on a connecting piece;
• and
• a second transmission means provided at one side of the first transmission means and parallel thereto, the second transmission means comprising a sleeve driven by the driving means to rotate, a second telescopic tube assembly accommodated within the sleeve and axially movable relative to the sleeve, and a second screw rod threadedly connected to the second telescopic tube assembly and linearly movable relative to the second telescopic tube assembly, an inner wall of the sleeve provided with a plurality of guiding grooves parallel to an axial direction of the sleeve, the second telescopic tube assembly provided with a positioning plug, a plurality of guiding rails protruded from an outer periphery of the positioning plug for slidably mating with each guiding groove, the guiding rails being non-rotatable relative to the guiding grooves, so as to make the second telescopic tube assembly be rotatable with the sleeve, one end of the second telescopic tube assembly connected on the connecting piece of the first transmission means, wherein the driving means simultaneously drives the first telescopic tube assembly of the first transmission means and the second telescopic tube assembly and the second screw rod of the second transmission means to protrude or retract relative to the driving means.

A lifting device having parallel double screw rods, comprising:

• a driving means;
• a first transmission means comprising a first screw rod driven by the driving means and a first telescopic tube assembly threadedly connected to the first screw rod and linearly movable relative to the first screw rod, a distal end of the first telescopic tube assembly fixedly connected on a connecting piece;
• and
• a second transmission means provided at one side of the first transmission means and parallel thereto, the second transmission means comprising a sleeve driven by the first transmission means to rotate, a second telescopic tube assembly accommodated within the sleeve and axially movable relative to the sleeve, and a second screw rod threadedly connected to the second telescopic tube assembly and linearly movable relative to the second telescopic tube assembly, an inner wall of the sleeve provided with a plurality of guiding grooves parallel to an axial direction of the sleeve, the second telescopic tube assembly provided with a positioning plug, a plurality of guiding rails protruded from an outer periphery of the positioning plug for slidably mating with each guiding groove, the guiding rails being non-rotatable relative to the guiding grooves, so as to make the second telescopic tube assembly be rotatable with the sleeve, one end of the second telescopic tube assembly connected on the connecting piece of the first transmission means, wherein the driving means simultaneously drives the first telescopic tube assembly of the first transmission means and the second telescopic tube assembly and the second screw rod of the second transmission means to protrude or retract relative to the driving means.