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:
Jan. 02, 2007
Filed:
Oct. 31, 2005
Shunichi Sato, Tokyo, JP;
Shunichi Sato, Tokyo, JP;
Other;
Abstract
A stationary yoke surrounds an outer peripheral surface of a ring-shaped permanent magnet in a certain distance. The ring-shaped permanent magnet is fixed to a rotor and has two poles of N, S poles in a diameter direction. The stationary yoke includes a first outside yoke and a second outside yoke overlapped in an axial direction and a hole element is disposed in a gap of the first outside yoke. An axial height of the first outside yoke changes along the circumferential direction and a height of the second outside yoke has a complementary relation with the height of the first outside yoke, and the first outside yoke and the second outside yoke are overlapped in a certain clearance. A ratio of an amount of the magnetic flux passing through the gap to an amount of the magnetic flux not passing through the gap changes with rotation of the ring-shaped permanent magnet and further, the change of the height causes a change in the magnetic flux amount flowing in the first outside yoke, thereby improving linearity of an output of a hole element.