Patent ID: 9472998
Filing Date: 2016-10-18
CPC Classification: H02K

Claim Text:
1. A linear actuator, comprising: a cylindrical housing having a first end and a second end; a first end cap attached to the first end of the cylindrical housing; a second end cap attached to the second end of the cylindrical housing; a stator attached to the cylindrical housing; a rotor rotatably interacting with the stator and comprising a hollow cup shaped permanent magnet and a screw shaft fixed to the hollow cup shaped permanent magnet and having a threaded end and a distal end; an output shaft co-axial and in screw coupling with the threaded end of the screw shaft, and extending through the first end cap; a bearing holder fixed to the cylindrical housing and having an end extending into the hollow cup shaped permanent magnet; a bearing attached to the end of the bearing holder within the hollow cup shaped permanent magnet to support the screw shaft; a load ball abutting the distal end of the screw shaft; a thrust bearing having a concave contact surface in contact with the load ball; and a spring attached to the second end cap and axially urging the thrust bearing towards the load ball, wherein the rotor further comprises a coupler fixed to the distal end of the screw shaft and having a through hole accommodating the load ball, the bearing is pressed between the coupler and a shoulder formed on the screw shaft between the threaded end and the distal end.