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:
Apr. 09, 2002
Filed:
Apr. 27, 1999
Wolfgang Hill, Karlsruhe, DE;
Other;
Abstract
Electric machines with a radial air gap field, but in particular low power EC external rotors, have advantageously individually spooled poles. The trapezoidal cross section of the slot and small slot openings towards the air gap make the realization of a compact winding difficult. In accordance with the invention, the body of the electric machine which form the individual poles is assembled from soft magnetic segments. The segments are preferably made of axially stacked sheet metal that have indentations on the edges forming the wall of the slot. The indentations enables the conductor wire to be guided in a precise manner during winding of the individual poles. At the air gap, pole shoes cover almost the entire perimeter and at the opposite end, they form adjacent pole segments, preferably with recesses, into which retention pins are axially inserted after mounting to ensure radial fixation. In multi-phase machines, spooled T-segments and non-spooled X-segments alternate in direction of the slot width with the X-segment possessing a pole surface that is fractionally enlarged in accordance with the number of phases. The invention enables highly efficient electric drive units to be produced at low cost.