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:
Nov. 15, 1988
Filed:
Dec. 15, 1986
Jayant G Vaidya, Rockford, IL (US);
Caio Ferreira, Rockford, IL (US);
Sundstrand Corporation, Rockford, IL (US);
Abstract
In order to optimize the electrical performance in motors in terms of improved efficiency, power factor, and reduced current, a position detecting apparatus utilizes a first magnetic sensing device for accurately determining the angular position of a rotor and a second magnetic sensing device for absolutely determining the angular position of the rotor. The first magnetic sensing device includes a first target operatively associated with the rotor so as to rotate therewith and also includes a first sensor disposed at a fixed distance from the first target independent of the absolute angular position of the rotor to define a first air gap therebetween and a first magnet is disposed in proximity to the first target and the first sensor to create a first magnetic field in the first air gap. With this arrangement, the first sensor cooperates with the first target to accurately determine the angular position of the rotor by detecting incremental variations in the first magnetic field in the first air gap. The second magnetic sensing device includes a second target operatively associated with the rotor so as to rotate therewith. A second sensor is disposed at a variable distance from the second target dependent upon the absolute angular position of the rotor to define a second air gap therebetween, and the second magnetic sensing device also includes a second magnet disposed in proximity to the second target and the second sensor to create a second magnetic field in the second air gap. With this arrangement, the second sensor cooperates with the second target to absolutely determine the angular position of the rotor by detecting continuous variations in the second magnetic field in the second air gap.