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:
Jun. 06, 1995
Filed:
Dec. 09, 1993
Detlef Prahl, Buehl, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A drum commutator for electrical machines has an isolating material drum and a plurality of commutator plates composed of an electrically conductive material, the commutator plates being mounted on a periphery of the isolating material drum near one another and electrically separated from one another by axial slots, each of the commutator plates being provided with a surface coating composed of carbon material and with a connecting lug for an armature winding of an electrical machine, each of the commutator plates having at least one depression at its lower side placed on the isolating material drum and being also provided with a radial passage which opens in the depression and has a reduced size relative to the depression, the carbon material of the surface coating filling the passage and the depression as a one-piece structure.