Dual cover pyramid, has smaller and larger pyramids that are combined in common pyramid, and includes axles driven by impellers, where bearing pressure is distributed over retainers that are fixed on arms

摘要

The pyramid has smaller and larger pyramids that are combined in a common pyramid, and includes axles driven by impellers (3, 9), where bearing pressure is distributed over retainers that are fixed on arms. The arms retain a glass bearing (11) in its center to enable installation of the smaller pyramid in the bearing. A hole is formed in the center of the retainers into which the axle of the smaller pyramid is inserted.