< Topic >Structure being simple, be able to produce cheaply, the linear actuator which can obtain big inertial forces without furthermore the magnetic neutron leakage is little, increases number of articles and/or making weight heavy, is offered.SolutionsThe output axis 12 which round trip linear motion unrestrictedly is supported in support case 11 and output axis 12 in the permanent magnet operation the fluctuation magnetic field 14 which is locked in the elastic member 13 which energization is done and output axis 12 and permanent magnet 14 on intermediate position side of round trip linear motion, output axis 12 the round trip straight line being the coil which it exercises to the pole of one side of permanent magnet, 14, opposing the coil to the other pole of 15 which it locks in support case 11 and permanent magnet 14 the halfway section to fit lock paralleling outside permanent magnet and 14 opening the opening vis-a-vis the said permanent magnet 14, the coilExtending to outside 15, the destal it had with the power source means in order to form the fluctuation magnetic field in the yoke 16 which consists of the magnetic substance which it makes approach makes lay out outside coil 15 and coil 15.< Choice figure >Drawing 1【課題】構造が簡単で安価に製作でき、しかも磁気漏れが少なく、部品点数を増やしたり重量を重たくしたりすることなく、大きな慣性力を得ることができるリニアアクチュエータを提供する。【解決手段】往復直線運動自在に支持ケース11に支持した出力軸12と、出力軸12を往復直線運動の中間位置側に付勢する弾性部材13と、出力軸12に固定した永久磁石14と、永久磁石14に変動磁場を作用させて、出力軸12を往復直線運動させるコイルであって、永久磁石14の一方の磁極に対向させて支持ケース11に固定したコイル15と、永久磁石14の他方の磁極に途中部を密着固定し、永久磁石14の外側に沿って該永久磁石14に対して隙間をあけてコイル15の外側まで延びて、端部をコイル15の外側に接近配置させた磁性体からなるヨーク16と、コイル15に変動磁場を形成するための電源手段とを備えた。【選択図】図1
