Patent · US Expired

Series-wound motor

US6713929B2 · kind B2 · utility

11Cited by
13References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 2002
Grant dateMar 30, 2004
Priority date
Expiry dateJun 30, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K1/148
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A series-wound motor is disclosed which is particularly suitable as a universal motor for an electric power tool. The motor comprises a stator with at least two field poles, each having two pole horns. At least one of the pole horns of each pole comprises first and second protrusions extending circumferentially from an axial edge of the pole horn. Sparking is reduced thereby. Also a retarded motor is disclosed, wherein each pole comprises a pole horn having a run-on edge, and further comprises a pole horn having a run-off edge. The pole horns having run-off edges are shortened in circumferential direction compared to the pole horns having run-on edges or comprise at least one cutout section extending in circumferential direction. The motor can be switched between a motor operation and a brake operation, without the need for providing commutating windings or additional coils to avoid excessive sparking.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.