| 摘要 |
<p>A resonant microwave cavity having end caps, including irises, which are made of a bi-metal or trimetal material. The end caps are affixed to the cavity walls in the usual manner. As temperature varies, the end caps, including irises, expand into or out of the cavity to compensate for the increase or decrease in length of the cavity walls due to variations in temperature. Therefore, as temperature varies, the bi-metal or tri-metal end caps maintain the volume of the cavity substantially constant. When a bi-metal end cap is used, each layer of metal has a different coefficient of expansion. When a tri-metal end cap is used, the centre layer has the highest coefficient of thermal expansion. The two outer layers have a lower coefficient of thermal expansion than the centre layer and can be the same or different. In previous devices to compensate for temperature variations in a cavity, the end cap is not affixed to the cavity in the usual manner but is built onto a plunger which increases or decreases in length with temperature.</p> |
