2026 年 19 巻 2 号 p. 80-89
This study presents the development of a bi-directional proportional solenoid actuator incorporating a Hall array micro-magnetic sensor within a movable coil. Drawing inspiration from hydraulic proportional directional control valves―typically dependent on linear variable differential transformers (LVDTs)―the proposed design leverages compact linear Hall sensors to enhance positional accuracy, reduce system complexity, and improve structural efficiency. The actuator enables precise control of both force and position, addressing the absence of inherent positional feedback in conventional solenoid systems. To characterize performance, JMAG finite element analysis was used to investigate magnetic circuit behavior, static force generation, and armature displacement, along with the correlation between Hall sensor output and armature position. Both simulation and experimental validation, conducted on a custom dynamic testing platform, demonstrate that the actuator achieves a maximum linear force exceeding 15 N, operates within a 0-2.0 A current range, and supports a 20 mm effective stroke (±0.2 mm). The system further supports multi-mode displacement outputs and integrates closed-loop control algorithms capable of micron-level precision over extended strokes. By eliminating LVDT sensors and associated signal conversion circuits, the actuator significantly streamlines the valve architecture, reduces manufacturing costs, and enhances system integration. These advancements expand the application potential of linear-motion solenoids in high-precision electromechanical systems, representing a notable progression in actuator technology.
