| 摘要 |
A linear actuator assembly, such as a rod or piston-type linear actuator, comprising a rotating lead screw with external threads; and a nut assembly with threads engageable with the external threads of the lead screw; and a guide tube having a hollow interior portion with at least one internal surface. The lead screw and nut assembly are located within the hollow interior portion of the lead screw, and the guide tube is configured to prevent the nut assembly from rotating with the lead screw. The nut assembly translates in a linear direction within the guide tube as the lead screw rotates. A portion of the nut assembly, such as a wedge, is radially biased against an internal surface of the guide tube. In one aspect, an axial compression spring is pre-loaded against the wedge and pushes the wedge up a ramp surface on the nut, and into the internal surface of the guide tube. The radially-biased wedge helps minimize torsional backlash in the assembly. The assembly can include a piston or rod that is attached to the nut assembly, and reciprocates into and out of the guide tube in a telescoping fashion. The nut assembly can also include an anti-backlash nut having a plurality of internally-threaded longitudinal flexure members. The axial compression spring that is pre-loaded against the wedge also drives the threads of the flexure members into the threads of the lead screw to minimize axial backlash. |
