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:
Aug. 02, 2011
Filed:
Jun. 03, 2009
Seung-jong Kim, Seoul, KR;
Jong Min Lee, Seoul, KR;
Woo Yeon Kim, Seoul, KR;
Korea Institute of Science and Technology, Seoul, KR;
Abstract
A linear motor includes a stator having teeth symmetrically formed on upper and lower surfaces thereof at regular pitch; a movable member including upper cores disposed above the stator, lower cores disposed below the stator in symmetrical with the upper cores, and yoke parts connecting the upper and the lower cores around the stator, wherein the upper and lower cores have upper and lower coils wound therearound, respectively; at least one gap sensor to detect the gap between the stator and the upper or lower core and the inclination of the movable member; a controller performing the levitation control by adjusting the amplitudes of currents applied to the upper and lower coils, based on the gap variation, and driving the linear motion by changing the current phases; and a multichannel voltage-to-current power amplifier of which each channel is connected to each coil of the upper and lower cores.