Method of producing a rotor

US6249957A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Martin Wiesler · Baden-Baden, DE
• Klaus Maldener · Achern, DE
• Martin Kiefer · Oberkirch, DE
• Lothar Fauth · Laufenburg (Baden), DE
• Hans Kobschaetzky · Renchen, DE
• Dieter Kern · Amawalk, US

Key dates

• Filing date: Oct 21, 1998
• Grant date: Jun 26, 2001
• Expiry date: Oct 21, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/49012
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

In rotors for electric motors, it is usual to fix the commutator on the rotor shaft by a press fit. In the present invention, the rotor shaft, with the rotor core fixed thereon, is electrostatically coated with an epoxy layer on opposite portions of the rotor shaft and in the winding slots, and is then heated to the plasticizing and curing temperature of the epoxy. After that, by a sliding tool, the commutator, whose inner bore has a clearance fit relative to the rotor shaft, is slipped onto the rotor shaft in a terminal position, in the process the still-viscous epoxy is pushed backward and is deposited radially on a connecting end face, forming a bead, and penetrates the annular gap between the inner bore and the rotor shaft. Once the epoxy layer has cooled, the commutator is fixed against rotation and displacement on the rotor shaft. The rotor is suitable for electric motors of various types.