Patent · US Expired

Armature for high-speed electric motors force-ventilated in air containing abrasive dust

US5352948A · kind A · utility

23Cited by

5References

10Claims

0Family size

Assignee

Robert Bosch GmbH · DE

Inventors

Manfred Kirn · Stuttgart, DE
Werner Grammer · Stuttgart, DE
Gerhard Kraemer · Igensdorf, DE
Meinhard Eule · Neckartenzlingen, DE

Key dates

Filing date	Jan 11, 1993
Grant date	Oct 4, 1994
Priority date	—
Expiry date	Jan 11, 2013

Classification

Technology area (CPC H)Electricity
CPC primaryH02K3/51
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

The armature (1) for high-speed electric motors force-ventilated in air containing abrasive dust, in particular in electric tools including right angle grinders, has windings which are laid in slots (7) of an armature laminate stack (5), and are held down in the slots (7) by elongated, elastic slot seals (15), and forth winding overhangs (9, 11) on the end faces of the armature. To increase the strength of the armature winding, the resistance to cooling air containing abrasive dust, and to improve the cooling, the slot seals (15) project over the slots (7), follow the contour of the winding overhangs (9, 11), in particular along surface lines, in the armature longitudinal direction, extend up to the end faces of the armature (1), and their ends are secured there by a ring (19) or cord winding (17).

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