Abstract: A power supply assembly for a vehicle includes a generator connected to an engine of the vehicle; a high-voltage bus to which the output voltage of the generator is supplied and to which a high-voltage load is connected; a low-voltage bus connected to the high-voltage bus via a voltage step-down element and to which a starter motor and a low-voltage load are connected; a high-voltage storage cell which a positive terminal thereof is connected to the high-voltage bus and a negative terminal thereof is grounded via a switch element; a low-voltage storage cell which a positive terminal thereof is connected to the low-voltage bus via a key switch and a negative terminal thereof is grounded; and a controller for controlling the opening and closing of the switch element, wherein the controller is constructed so as to monitor the starting and stopping of the engine based on start and stop signals form the engine, and open the switch element when the stopping of the engine is detected.

Abstract: A car power supply system which can improve the installation freedom of an engine and safety against crash and obtain high output for a large-capacity electric load. The car power supply system comprising: first and second generators which are smaller in size than a generator which is large in size and obtains high output for a large-capacity electric load by itself; and a controller which causes the first generator to generate power by the start of an engine and causes the second generator to generate power when it detects that a vehicle is braked, wherein high output is obtained for the large-capacity electric load with the first and second generators.

Abstract: A stator of a vehicular alternating current generator comprising: a stator core having slots; and a stator coil wound in the slots of the stator core; wherein a resin having a peak or peaks of a loss tangent which is a value of a loss elastic modulus divided by a storage elastic modulus in a temperature range of from 100.degree. C. to 250.degree. C. is provided among coil strands of the stator coil and/or between the stator core and the stator coil.

Abstract: An output power control device for an automotive AC generator includes a field current limiter circuit 9 for controlling the duty factor of the power transistor 305 coupled in series with the field coil 102A of the AC generator 1A, which is supplied with a maximum field current twice the conventional level. A frequency-to-voltage converter 903 converts the input frequency to a voltage corresponding to the rpm of the AC generator 1A, and a comparator 909 compares the sawtooth waveform generated by a sawtooth waveform generator 908 with the output of the frequency-to-voltage converter 903, the upper level of which is limited under a predetermined level by resistors 904 through 906 and a diode 907. When the rpm of the AC generator 1A exceeds a predetermined frequency, the pulse train generated by the comparator 909 reduces the duty factor of the power transistor 305, thereby controlling the level of the output current generated by the AC generator 1A.

Abstract: An AC generator for use in a vehicle which can cool sufficiently a coil portion of a stator coil by means of cooling airs blowing through from a plurality of air suction holes to a plurality of air exhaust holes, the airs being produced by fans provided in a rotor. A stator coil is constructed such that a distance from a front end of the coil to a rear end of the coil is overlapped sufficiently on the distance between the blades of fans in the axial direction thereof.

Abstract: The present invention of an AC generator for use in a vehicle in which front and rear brackets hold a stator there-between and support rotatably a rotor theirbetween inside the stator. A pair of magnetic pole cores mounted on the rotor has end surfaces and holds an exciting coil theirbetween. Two fans are mounted on the end surfaces, respectively, so as to produce cooling blow. wherein said magnetic pole cores are formed such that a height in a circumference direction thereof is greater than a length between said two surfaces to thereby increase an area thereof to be in contact with said exciting coil, so that the transfer and diffusion of the heat of the exciting coil to the magnetic pole can be performed.

Abstract: A rotor for a vehicle dynamo includes a field coil bobbin (6) provided with ventilation slots (6a) and a heat conductive material (7) provided between the bobbin and the field cores, whereby the heat radiation from the field coil is increased. The bobbin is provided with a cylindrical portion and a pair of opposed flange portions which include at least one ventilation opening extending from the cylindrical portion into the flange portions.