Abstract: A flywheel assembly is provided which comprises a housing, a flywheel rotatably mounted in the housing and defining an inner and an outer circumferential surface, and an inner body spaced radially and inwardly from the inner circumferential surface of the flywheel. The flywheel rotates in use around and relative to the inner body, the assembly defines an engagement surface spaced radially and outwardly from the outer circumferential surface of the flywheel, and the inner body is flexibly coupled to the housing. If the flywheel mounting fails during rotation at speed leading to displacement of the flywheel, flexure of the coupling as a result of forces exerted on the inner body by the displaced flywheel allows the flywheel to contact the engagement surface.

Abstract: A flywheel assembly is described which is suitable for use as a compact power storage device. The assembly comprises a housing, a flywheel coupled to a shaft which is rotatably mounted in the housing via bearings, a primary chamber which is defined within the housing and contains the flywheel, and a secondary chamber which is defined within the housing and contains the bearings. Furthermore, it includes a molecular pump driven by the shaft for pumping gas molecules from the primary chamber to the secondary chamber. Location of the bearings in a high pressure chamber inhibits off-gassing from the bearing grease. Furthermore, any such off-gassing under load will not increase the gas pressure in the first chamber containing the flywheel as it is separate from the secondary chamber containing the bearings.

Abstract: A flywheel assembly is described which is suitable for use as a compact power storage device. The assembly comprises a housing, a flywheel coupled to a shaft which is rotatably mounted in the housing via bearings, a primary chamber which is defined within the housing and contains the flywheel, and a secondary chamber which is defined within the housing and contains the bearings. Furthermore, it includes a molecular pump driven by the shaft for pumping gas molecules from the primary chamber to the secondary chamber. Location of the bearings in a high pressure chamber inhibits off-gassing from the bearing grease. Furthermore, any such off-gassing under load will not increase the gas pressure in the first chamber containing the flywheel as it is separate from the secondary chamber containing the bearings.

Abstract: A flywheel assembly is provided which comprises a housing, a flywheel rotatably mounted in the housing and defining an inner and an outer circumferential surface, and an inner body spaced radially and inwardly from the inner circumferential surface of the flywheel. The flywheel rotates in use around and relative to the inner body, the assembly defines an engagement surface spaced radially and outwardly from the outer circumferential surface of the flywheel, and the inner body is flexibly coupled to the housing. If the flywheel mounting fails during rotation at speed leading to displacement of the flywheel, flexure of the coupling as a result of forces exerted on the inner body by the displaced flywheel allows the flywheel to contact the engagement surface.