Robert Boschgmbh

Dieter Kern

Lothar Fauth

Martin Kiefer

Klaus Maldener

Hans Kobschaetzky

Martin Wiesler

In rotors for electric motors, it is usual to fix the commutator on the rotor shaft by means of a press fit. In the present invention, the rotor shaft, with the rotor core fixed thereon, is electronically coated with an epoxy layer on opposite portions of the rotor shaft and in the winding slots, and is then heated on the plasticizing and curing temperature of the epoxy. After that, with the help of a sliding temperature, 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.

Method of producing a rotor

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.

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Buehlertal, Germany

Dieter Kern