Simulation Approach to Effect of Elasticity on Actuation Time of Displacement-amplified Electromagnetic Actuator

Although various kinds of actuators have been developed, electromagnetic actuators have advantages in their ease of use and the abundance of environmental devices. Displacement-amplified electromagnetic actuators (DAEAs) have been studied owing to their efficient use of electromagnetic attractive force. DAEAs magnify the motion of the change of a gap in which the electromagnetic attractive force is generated, and utilize the large force in the small gap between an electromagnetic core and an armature, also achieving fast reciprocated motions from the advantage in fast driving. We have analytically and experimentally studied the effect of displacement amplification on actuation time in which a load is carried for a certain distance under constant current. The preliminary attempt revealed that the amplification contributes to a decrease in the actuation time of actuators using electromagnetic attractive force in some cases. Although the early studies only considered simple mass loads, spring components were often used in prototypes and applications of DAEAs to realize bidirectional motion with simple structures. Therefore, it is important to clarify the elastic effect on the driving characteristics of DAEAs. This study involves the conduction of a simple simulation to reveal the effect of elasticity on the actuation time of DAEAs. The simulation results indicate a range of amplification ratios for which the actuation failed owing to the effect of the spring.