| 摘要 |
PURPOSE:To obtain a current lead which has preferable cooling characteristics by cutting linear slits in combination with a spiral step on the peripheral surface of a lead conductor material, and connecting slits in series therebetween to form a spiral groove and a heat sink fin. CONSTITUTION:A lead conductor 8 of round rod is indexed to n sections (indexed at 90 deg. in case of n=4). When the pitch of a heat sink fin 11 is p, the position is displaced by x=p/n axially between adjacent sections and linear slits 10a are cut so that the groove width (a) become p>a>x, the slits 10a are connected in series to form a spiral groove 10. The depth (b) is the size for crossing part of the adjacent slit at the end of the slit except the prescribed energizing section at the center of a thin unit 8. Since the slit is linear, it can be formed to be narrow and deep by a milling machine to obtain a large heat sink area, cooling gas becomes disturbulent in a step between the slits 10 to further increase a thermal exchangeability. |
