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:
May. 15, 2007
Filed:
Jun. 28, 2005
Thord Agne Gustaf Nilson, Tyresö, SE;
Thord Agne Gustaf Nilson, Tyresö, SE;
Danaher Motion Stockholm AB, Stockholm, SE;
Abstract
An induction motor comprises a stator () and a rotor (), which includes material essentially blocking magnetic flux at high frequencies. A difference in number of stator slots and rotor slots is chosen so that the inductance of a winding provided in a stator slot is different from the inductance of a winding provided in another stator slot. A sense means, such as stator winding or separate sense winding, is provided in at least one of the stator slots and the sense means is arranged to allow measuring of the inductance thereof. The sense means constitutes an integrated sensor, which is both inexpensive and reliable. A method of sensing the rotor position and/or speed of an induction motor is also described.