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:
Dec. 17, 2002
Filed:
Jul. 19, 2001
Kwan Yuhl Cho, Seoul, KR;
Hak Woon Kim, Anyang, KR;
LG Electronics Inc., Seoul, KR;
Abstract
An apparatus for sensing a laundry amount in a washing machine includes: a rectifier; an inverter receiving a DC voltage and converting it to a three-phase AC voltage, a BLDC motor driven by the three-phase AC voltage from the inverter, a rotor position detector detecting the position of a rotor of the BLDC motor; a microcomputer outputting a control signal for controlling a switching operation of the inverter according to the position detect signal of the rotor position detector and a current control signal; a gate driving unit receiving the control signal from the microcomputer and outputting a gate drive signal to the inverter; a torque command generator generating a torque command signal corresponding to a speed set by a user; a torque controller operating the torque command signal from the torque command generator and outputting a q-axis current command signal; a current controller outputting the current control signal according to the q-axis current command signal from the torque controller and a d-axis current command signal; a speed detector detecting a driving speed of the BLDC motor according to the position detect signal of the rotor position detector; a laundry amount sensor comparing the speed detect signal from the speed detector with a previously stored reference speed and sensing a laundry amount; and a current command unit applying the d-axis current command signal to the current controller according to the speed detect signal from the speed detector.