In mechanical equipment, linear precisiom screws are of great significance as transmission components that enable the conversion between rotational and linear motion. Based on structural distinctions, linear motion screws are mainly classified into three types: planetary roller screws, ball screws, and trapezoidal screws.
Planetary roller screws are the top-performing sub-category within the linear screw family, yet they come at a higher cost. This type combines the principles of a planetary reducer and a screw shaft innovatively. Around the main threaded shaft, 6 to 12 threaded rollers are arranged in a planetary configuration. This design shifts the traditional point-contact of ball screws to a line/surface contact, enhancing precision and load-bearing capacity. Specifically, its load-bearing capacity is 6 to 15 times that of ball screws with the same precision, and its lifespan is over 10 times longer.
Ball screws consist of a nut, a threaded shaft, and balls. During operation, the motor rotates the threaded screw, and the balls in the nut's internal raceways drive the nut to move linearly, thus achieving efficient linear transmission.
Trapezoidal screws are made up of a nut and a threaded shaft. These two components are in direct contact, resulting in linear sliding. Trapezoidal screws are characterized by excellent self-locking properties, but they have relatively low transmission efficiency.
