What Is a Current Induction Terminal?
A current induction terminal, also known as a feedthrough, is a terminal component used to deliver substantial power to the interior of vacuum and pressure equipment.
These terminals are employed to supply power for heating purposes or other electrical requirements while maintaining a sealed environment within vacuum and pressure equipment. They achieve electrical insulation using ceramics or other suitable materials, allowing power to be delivered solely to the necessary electrodes. These terminals are both chemically and thermally resistant, ensuring stable performance. Various types are available based on the number of electrodes, flange shape, and other factors. Some manufacturers even offer customized products as per specific requirements. Due to the need for both high airtightness and electrical insulation, a specialized hermetically sealed structure is applied.
Uses of Current Induction Terminals
Current induction terminals find application in manufacturing, processing, and academic research fields that involve vacuum and pressure vessels. They serve various purposes, including object detection and control, signal extraction for measurements, and engineering applications, all requiring the application of current or voltage within specialized vessels.
Structure of Current Induction Terminals
A core wire, through which current or voltage is conducted, passes through a metallic component like a flange. Power is then supplied from the exterior into the vacuum environment through this core wire. To ensure power is directed only to the necessary electrodes, insulating materials such as ceramics are used to electrically insulate the terminal from the ground.
A special sealing structure, known as a hermetically sealed structure, is employed to prevent gas leakage within the vessel. This structure takes advantage of the difference in thermal expansion coefficients between insulators and metals. In the case of glass, which has a relatively low coefficient of thermal expansion, sealing is accomplished by applying compressive stress from the metal to the glass. By adjusting the compressive stress appropriately, a high level of airtightness is achieved.