Method 1: The screw is fixed at one end and supported at the other end. The fixed end bearing is subjected to axial and radial forces; the end bearing is only subjected to radial forces and can be used for a small amount of axial float, which has the advantage of avoiding or reducing the bending of the screw due to its own weight. At the same time, the thermal deformation of the lead screw can be freely extended to one end.
Method 2: The screw is fixed at one end and one end is free. The fixed end bearing is subjected to axial and radial forces. This type of support is used for short stroke short screws. The advantage is that it is easy to assemble and has less impact on geometric accuracy. It is suitable for short screws and vertical screws. However, it also has some drawbacks. The spacing between the points is small and the rigidity is relatively low. the difference.
Method 3: Screw fixing and nut rotation transmission mode At this time, the nut rotates while moving along the axial direction of the fixing screw: since the screw does not move, the limit rotation speed can be avoided, and the elongated ball screw can be avoided at high speed. Various problems have arisen. The advantage is that the nut has a small inertia, flexible movement and high speed. A large pre-tension can be applied to the screw to increase the rigidity of the screw support and compensate for the thermal deformation of the screw.
Method 4: Both ends of the screw are fixed. Fixed end bearings can withstand axial and radial forces. This support can apply an appropriate pre-tension to the screw, increase the rigidity of the screw support, and partially compensate for the thermal deformation of the screw. The advantage is that the spacing between the operating points is greater and the stiffness is better; but the disadvantages are also unavoidable and more susceptible to the geometrical accuracy of the combined components.