A brushed motor includes a shaft inserted in a cylindrical stator, a rotor including a core provided on an outer circumference of the shaft to face the stator and a coil having a distributed winding structure wound around teeth of the core, a commutator provided on one end of the shaft, and electrically connected with the coil by a wire drawn from coil end parts of the coil, a resin molded part covering the coil end parts and a hooking portions for the wire of the commutator, and a brush in contact with an outer circumference of the commutator. A width of a gap between the resin molded part and the brush is set to a value larger than a scattering distance of a spark generated between the commutator and the brush.

Disclosed is an excitation device which includes a brush holder base. The brush holder base is provided with a plug. The plug is provided with a brush holder shaft. The front end of the brush holder shaft is provided with a brush box. A horizontal taper dovetail groove is formed in the brush holder base. A horizontal taper dovetail lug boss is disposed on the plug. The dovetail groove is matched with the dovetail lug boss. The present invention solves the problem of potential safety hazard in locking, and ensures safe and smooth operation of a unit.

An electric direct current motor is disclosed which includes a shaft, a winding support, a collector having several collector wires, and an air-cored outer rotor winding with several winding terminations. The outer rotor winding is at one end connected to the shaft via the winding support in a torque-proof manner, and is electrically connected with the collector. The winding support can be replaced by a printed circuit board as a bearing component of glass-fiber reinforced thermosetting plastics, wherein the printed circuit board includes at least one layer and is connected to the shaft via a metal hub.

An electric motor includes a stator and a rotor. The rotor includes a motor shaft, at least one radial fan and at least one axial fan being non-rotatably situated on the motor shaft for motor cooling. The radial fan is situated in the area of one axial end of the motor shaft and the axial fan is situated in the area of a diametrically opposed axial end of the motor shaft.

An electrical machine with a brush commutator arrangement (1) is proposed. Brushes (3) and a commutator (5) are adapted and arranged such that, upon operating the electrical machine (1), the brush (3) and the commutator (5) are displaced relative to each other in a lateral displacement direction (7) and a contact surface (9) of the brush (3) mechanically contacts a contact surface (11) of the commutator (5) along an overlapping area (13) thereby generating an electrical contact. Accordingly, an electric current is transmitted between brush (3) and commutator (5) through the overlapping area (13). An orthogonal electrical conductivity of the brush (3) and/or the commutator (5) in a direction (25) orthogonal to a respective contact surface (9, 11) locally varies along the lateral displacement direction (7). An orthogonal electrical conductivity distribution in the brush (3) and/or the commutator (5) is adapted such that, even when operating the electrical machine at maximum allowable power, for at least 90% of all spatial configurations during displacing the brush (3) and the commutator (5) relative to each other, an electrical current density through the overlapping area (13) does not exceed 130% of a rated maximal average electrical current density through the brush commutator arrangement (1). Due to the specific variation of orthogonal electrical conductivity within the brush (3) or commutator (5), sparking and resulting wear in the proposed brush commutator arrangement (1) may be reduced.

A rotor includes coils that are formed by winding wires around bobbins of a core, terminals which are arranged on the bobbins and to which end portions of the wires are hooked, and a commutator arranged at an end portion of the core on a side where the terminals are arranged. The terminals and commutator segments of the commutator are electrically connected via metal pieces extending from the commutator segments and via a wiring board.

An electric direct current motor is disclosed which includes a shaft, a winding support, a collector having several collector wires, and an air-cored outer rotor winding with several winding terminations. The outer rotor winding is at one end connected to the shaft via the winding support in a torque-proof manner, and is electrically connected with the collector. The winding support can be replaced by a printed circuit board as a bearing component of glass-fiber reinforced thermosetting plastics, wherein the printed circuit board includes at least one layer and is connected to the shaft via a metal hub.