| 摘要 |
<p>A lower rectangular sheet (1) is made of steel and fitted with a sealing element (3) of a heat resistant material. An upper sheet (2), preferably made of copper, slightly smaller than the lower sheet (1), is positioned within the sealing element (3) and on top of the lower sheet (1). A vacuum creating unit is joined to the lower sheet (1) from below. The lower sheet (1) and the sealing element (3) can be provided with integrated coolant ducts.</p> |
