Solenoid actuator and multi-solenoid actuator exerting constant force

Abstract

Disclosed are a solenoid actuator and a multi-stage solenoid actuator for transmitting a constant force. The solenoid actuator includes a tubular solenoid, a power unit capable of applying current to the solenoid, and a magnetic pair member having two magnetic members providing magnetic fields formed such that respective first poles thereof face each other and respective second poles thereof different from the first poles are located at both distal ends, and extending through the tub of the solenoid. The multi-stage solenoid actuator includes a solenoid assembly where at least two tubular solenoids are regularly aligned such that inner spaces of the tubes of the solenoids are arranged in series, a power unit capable of individually applying current to each solenoid of the solenoid assembly, at least one magnetic pair moveable unit having two magnetic members providing magnetic fields formed such that respective first poles thereof face each other and respective second poles thereof different from the first poles are located at both distal ends, and extending through the tub of the solenoid assembly, and a controller for determining and controlling a solenoid to receive the current from the power unit depending on a position of the magnetic pair moveable unit.

Dependencies are inferred from the claim text.