| 摘要 |
PURPOSE:To enable to perform a preferable cooling effect in an AC generator by cooling a negative discharge plate to a bracket via thermal conduction, reducing the area of a negative electrode heat sink plate instead of the cooling effect to allow a positive plate heat sink plate to contact directly with cooling air. CONSTITUTION:A heat sink plate is formed substantially in U shape, positive and negative diodes 15, 16 are respectively press-fitted on positive and negative heat sink plates 12, 11, and secured by screws 13 to a rear bracket 4 through an insulator between the both plates. When the diameters of the plates 12, 11 are designated by D1, D2 and the diameters of diodes 15, 16 are designated by d1, d2, they are superposed at the positional relationship to become D1>D2, d1>d2, d1>=d2. Thus, the cooling air intaken from a vent hole formed at the bracket 4 in a direction P is contacted with the both plates. Since the diode 15 is disposed on the outer periphery of the heat sink plate with fast air with less ventilating resistance, the positive side heat sink which cannot be expected for thermal conduction to the bracket can be preferably cooled. |
