PROTECTIVE DEVICE FOR TRANSISTOR

摘要

PURPOSE:To improve the efficiency of heat dissipation by providing the maximum heat generating section of a power transistor with a heat dissipation means in the power transistor used for an air conditioner for an automobile. CONSTITUTION:A power transistor 1 is fixed to a base 22 by using screws 21, and a support plate 23 is mounted at a regular interval l from the base 22. A heat dissipating bar 24 as a hollow bar and a hollow bar 26 in which a conductor 25 passes are fitted between the base 22 and the support plate 23. Since the heat dissipating bar 24 is joined with a lower surface 11 as the maximum heat generating section of the power transistor, heat generated in the transistor 1 is dissipated efficiently to the outside through radiator fins 27. Various circuit parts 28 for an air conditioner for an automobile are incorporated to the lower section of the support plate 23. A transistor protective device 20 constituted in this manner is arranged in a duct for the air conditioner in order to improve the effect of heat dissipation.