Steering actuator based on a ball screw with a separator

Abstract

This paper considers the issue of improving the reliability of an electromechanical actuator in which the possibility of ball screw jamming has been excluded. For this purpose, an analysis of design solutions which allows to increase the reliability of an electromechanical ball screw linear actuator was carried out, design of ball screw with a separator was developed and patented, experimental studies of an actuator prototype with ball screw with a separator were carried out. The proposed constructive solution of ball screw, in which the nut is made without an internal thread, significantly simplifies the design and manufacturing technology. For experimental determination of static and dynamic characteristics of the actuator containing ball screw with a separator a mathematical model has been designed and a prototype similar to the electromechanical actuator with ball screw with ball recirculation has been made. The experiments showed that compared actuators have practically same static and dynamic characteristics, but the efficiency of the ball screw with a separator is lower than that of ball screw with ball recirculation, the reasons for the decrease and ways to increase efficiency in ball screw with a separator are considered.

Design of patient lifting device based on the use of a worm gears mechanism in the protection of the caregiver

“…Ball screws are mechanisms for transferring force and movement, and friction and wear are always in the screw wing system [ 16 ] . In addition, studies have been carried out to improve the reliability of an electromechanical actuator, in which the possibility of ball screw jamming has been eliminated by considering the separator between the balls [ 17 ] . One of the main problems in developing machines with this kind of mechanism is the need for high torque to lift the patient from the bed.…”