The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 13, 1996
Filed:
Sep. 22, 1993
Timothy A Erhart, Chanhassen, MN (US);
Exlar Corporation, Chanhassen, MN (US);
Abstract
The present invention provides an electrically powered linear actuator including an actuator assembly (having an actuator rod and a thread engaging portion), a motor assembly (having a stator) and a housing assembly. An elongated cylinder formed of a magnetic material is rotatably supported relative to the housing assembly. Magnets or other elements are mounted about an outer circumference of the cylinder to form an armature within the motor assembly. The elongated cylinder of the armature further includes an internally threaded bore. The thread engaging portion of the actuator assembly is moved along the threaded extent of the cylinder on rotation of the cylinder. Thus, the cylinder functions as an armature drive cylinder. The stator is selectively energized to rotate the armature drive cylinder clockwise or counterclockwise to reciprocally move the thread engaging portion of the actuator assembly and the output shaft. The threaded bore of the cylinder is significantly longer than the thread engaging portion of the actuator assembly such that the difference therebetween defines an actuation stroke for the device.