Robert Boschgmbh

Joachim Severing

Friedhelm Meyer

Wolfgang Kurz

To provide a positive indication that a battery has been reversely connected to a self-contained electrical network, for example a vehicular or boat network, a diode (24) of low current carrying capacity is connected across the terminals (25, 26) of the network, poled in blocking direction. Upon erroneous or reverse connection of the battery (13) with reverse terminals, the diode will immediately burn out, thus providing positive identification of such a reverse connection, even if only of such short time duration that the main rectifier diodes were not yet damaged. To prevent spurious replacement of the diode and thus elimination of the indication, the diode (24) can be molded into or cemented into a depression or groove formed in the insulating support plate (28) supporting the rectifier element.

Automotive electrical power supply system with reverse polarity

Auxiliary windings wound in close juxtaposition to the respective phase windings of a three-phase alternator are connected in series with the star-connected phase windings at one end and at the other end to the diodes of a separate rectifier bridge for the current supplied to the exciter winding of the alternator. This makes possible operation of the exciter winding at higher voltage and lower current than in the case where the excitation voltage is generated only by the main phase windings of the alternator. Since the excitation windings carry only the exciter current, they may be made of finer wire than the main phase windings, but they should be wound close to the main phase windings so as to be cut in the same way by the lines of force of the rotating field. The current supply for the voltage regulator which controls the excitation current is obtained either from the output of the main rectifier bridge that is connected to the storage battery or from still another rectifier fed by the main phase windings of the alternator only. Pre-excitation current is provided from the battery through a monitor lamp and a diode.

Alternator-rectifier unit with higher voltage excitation circuit

To provide an easily and essentially automatically manufactured rectifier array for an automotive alternator, two bus rails 1a, 1b, in the form of sheet metal strips, are punched for insertion of connecting studs 6 of rectifier diodes. The bus rails, with the diodes assembled thereto, are placed parallel to, and spaced from each other, and oppositely directed studs 6 from the diodes 4 are connected together by connecting strips 2a, 2b, 2c, which will function as electrical connecting elements and heat sink and heat dissipating plates to conduct off heat arising in operation of the diodes. The subassembly can then be connected into an alternator, with an air directing baffle directing axial airflow. The angled-off cooling and connecting strips which, preferably, are wider than the bus rails, permit placing the assembly to fit around the alternator shaft and associated structures, such as slip rings and the like, with airflow being directed along the major plane of the respective rails and strips, thus permitting efficient flow of cooling air past the strips, efficient cooling, and essentially automated assembly.

Growing community of inventors

Ludwigsburg, Germany

Joachim Severing