Abstract: In the case of assembly after the insertion of the rotor (4-7) with the commutator (4) into the motor housing (8), in order to be able to install the brush holder (1), with its brushes (1.1; 1.2) which are subject to radial spring pressure, simply and in a manner which can be carried out by an automated machine it is proposed that: the brush holder (1) is pushed onto one end part (2.1) of an installation mandrel (2) which is in the form of a sleeve and whose other end (2.3) is placed on the commutator (4), together with an integrated restraining part (3) which holds the brushes (1.1; 1.2) in a raised installation position; and that the restraining part (3) is fixed outside the motor housing (8) by means of a conical expansion of one end part (2.1). The brush holder (1) is then moved into its final position with the brushes (1.1; 1.2) which now slide on the installation mandrel (2 ). The brushes (1.1; 1.2) are pressed radially onto the commutator (4) during the withdrawal of the installation mandrel (2).