| 摘要 |
PURPOSE:To prevent flashes of molding material from occurring and productivity from lowering due to occurrence of the flashes by providing a temperature retaining means on either plural top middle plates or plural bottom middle plates which support the top plates and the bottom plates respectively and apply compression to them. CONSTITUTION:A pair of electric heaters 15 and of temperature detectors 16 (temperature supporting means) are equipped respectively on plural top middle plates 5 to keep the tip middle plate 5 at a specified temperature and to prevent the temperature distribution of the top plate 3 and top cavity 1 from becoming ununiform. Therefore, no thermal deformation occurs on the top plates 3 and the top cavity 1 and the top cavity 1 and the bottom cavity 2 are stuck closely through a lead frame. In this manner, the molding material is prevented from leaking out of the cavity and changing into flashes, therefore, the yield of products and the productivity is improved. |
