Vacuum pump

摘要

The invention relates to a vacuum pump for use in a nuclear fusion plant. The vacuum pump according to the invention comprises a multiplicity of vacuum pump units which are each encapsulated individually in casing blocks and, by means of their casing blocks, are inserted in a common outer casing. The individual vacuum pump units can be designed for different evacuation rates, so that the pump according to the invention is optimally adapted to the load requirements at any particular time. As a result of the multiplicity of pump units, the diameter of the impeller blades, made of brittle ceramic material, of the turbomolecular part can be kept relatively low, so that the risk of said blades being destroyed is correspondingly low. If such destruction should nevertheless occur, the encapsulated embedment of the vacuum pump units in question prevent adjacent pump units from being adversely affected. The outer casing in this case ensures that any radioactive gas which may be present in the destroyed pump unit cannot escape into the environment. Advantageously, provision is further made for the voids in the pump, for example between the outer casing and the individual encapsulation casings, to be filled with a coolant liquid such as water, which, at the same time, serves as an irradiation protection jacket. <IMAGE>