A thermionic fuel element for electrical power generation having an all bonded sheath-sheath insulator collector assembly. The thus bonded assembly is provided with at least one internal groove by which an emitter intercell sub-assembly is bonded to the first-mentioned assembly. The subassembly is constructed to provide the required electric interconnections between a series of interconnected collector-emitter units or cells as well as providing passageways for an alkali metal vapor located in an interelectrode space, while providing proper spacing between the collector and emitter units thereof. In addition each sub-assembly includes means which readily allows the sub-assembly to be inserted, aligned and secured to the first-mentioned assembly while supporting the emitter, maintaining the emitter to collector gap, and providing a heat transfer path to the first-mentioned assembly.
A support is provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.
A support is provided for use in a thermionic converter to support an end an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially at its temperatures changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housng, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.
