Static Thrust Improvement of a Linear Proportional Solenoid

A linear proportional solenoid (LPS) is an actuator for a proportional control valve used in hydraulic pressure-control devices. The LPS thrust must be constant over a specified displacement range, and must be proportional to the current. This paper describes simulations of the thrust-displacement characteristics of LPSes as determined by FEM, conducted with the aim of improving the LPM thrust. In model P, where high flux-density permendur was used in the LPS stator and mover, the maximum thrust increased from 27 to 40 N. The range of constant thrust, however, decreased from 1.0 to 0.5 mm. In model S, where permendur was used in the stator and mover, and the salient pole of the stator in the LPS was modified, the range of constant thrust was the same as in the present model. Moreover, the static thrust in the range of constant thrust increased from 27 to 38 N.