PROBLEM TO BE SOLVED: To return an actuator to a returned state by compensating driving force when the driving force for driving the actuator fails.SOLUTION: An electric actuator includes a housing 10, a motor 20, a driving force transmission mechanism 30 for transmitting driving force of rotation by the motor 20, a driving shaft 40 disposed axially movable forward and backward, a ball screw mechanism 50 converting the driving force of the rotation from the driving force transmission mechanism 30 into linear driving force, to axially drive the driving shaft 40, and energization means 60 for energizing the driving shaft 40 in the axial direction. The ball screw mechanism 50 includes a screw shaft 51 coaxially connected to the driving shaft 40 and having a threaded groove on an outer peripheral face, a nut 52 disposed coaxially with the screw shaft 51 and having a threaded groove on a position corresponding to the threaded groove formed on the screw shaft 51, on an inner peripheral face, a ball disposed on both thread grooves, and a co-rotation prevention mechanism 53 for preventing co-rotation of the screw shaft 51 and the nut 52.SELECTED DRAWING: Figure 1
【課題】アクチュエータを駆動する駆動力が失陥したときに、その駆動力を補ってアクチュエータを復帰状態に戻すこと。【解決手段】ハウジング10と、モータ20と、モータ20による回転の駆動力を伝達する駆動力伝達機構30と、軸方向に進退可能に設けられた駆動軸40と、駆動力伝達機構30からの回転の駆動力を直線駆動力に変換して、駆動軸40を軸方向に駆動するボールねじ機構50と、駆動軸40をその軸方向に力を付勢する付勢手段60と、を備え、ボールねじ機構50が、駆動軸40と同軸に連設され、外周面にねじ溝が形成されたねじ軸51と、ねじ軸51と同軸に設けられ内周面にねじ軸51に形成されたねじ溝と対応する位置にねじ溝が形成されたナット52と、両ねじ溝に介在して設けられたボールと、ねじ軸51がナット52と共回りするのを防止する共回り防止機構53と、を備えた電動リニアアクチュエータを構成する。【選択図】図1
ELECTRIC LINEAR ACTUATOR
電動リニアアクチュエータ
2016-09-05
Patent
Electronic Resource
Japanese