Patent ID: 8698362
Filing Date: 2014-04-15
Classification: B24B,B25F,H02K

Abstract:
1. An electric power tool having an electric motor that is automatically cooled by a cooling air flow, and the electric motor has an armature and a field iron packet disposed concentrically to the armature, and the armature and the field iron packet are disposed in series in the cooling air flow, wherein the armature and the field iron packet are disposed in a cooling passageway, in which a fluidic partition is provided between a first cooling passageway portion and a second cooling passageway portion; wherein the cooling air that flows through the first cooling passageway portion is aspirated through a first cooling air inlet that is disposed adjacent to an upstream end of the first cooling passageway portion; and wherein a suction region for aspirating additional cooling air is disposed adjacent to the armature on a downstream end of the second cooling passageway portion and wherein the fluidic partition extends from the suction region to the field iron packet, wherein the fluidic partition is configured to separate the first cooling air inlet from the suction region such that the cooling air aspirated through the first cooling air inlet does not enter the suction region until after flowing through the first cooling passageway portion and the second cooling passageway portion.