For a conventional thrust bearing to support the weight of a heavy rotor, it is necessary to force high-pressure fluid in from the outside, since it is difficult to realize fluid lubrication using lubricating oil, even with a sliding bearing (static pressure bearing).
However, for this thrust bearing with a screw pump function, lubricating oil pressure on the bearing surface can be easily increased without supplying lubricating oil from the outside. Thus, this bearing makes it possible to float a heavy rotor, such as a turbine or a large vertical shaft-type wind power generation device, from the bearing surface and realize low friction through fluid lubrication (Figure 1, Figure 2). In addition, in a water flow power generation device in which a heavy vertical axis water turbine is directly hung from the bottom of a ship, it is also possible to float the heavy water turbine from the bearing surface (Figure 5).
Moreover, with this thrust bearing, it is also possible to remove lubricating oil on the bearing surface, which has become subject to high pressure, at once and force it to return to the top of the screw pump by rotating the generator shaft at high speed using an external hydraulic motor. Therefore, even wind or water turbines that rotate at low speeds can be used to generate power without an accelerator. In this case, circulation of the lubricating oil also has the effect of carrying the friction heat of the bearing outside and preventing overheating (Figure 6).

In a conventional rotary joint for super-high-pressure gas, gas may leak from the labyrinth structure if the pressure of the gas becomes too high.
If using this thrust bearing with a screw pump function, when lubricating oil is pushed by high-pressure gas and is about to leak outside, the screw pump function operates more forcefully due to the rising of the screw part’s lubricating oil surface, applying a force that repels the lubricating oil. In other words, as the internal gas pressure increases, the lubricating oil is pushed down by an increasing number of screw threads, and opposing lubricating oil is forced toward the bearing surface against the gas, which is at a much higher pressure than in a conventional rotary joint, thereby realizing a rotary joint that has no gas leakage. In this case, as in the case of (1), a heavy rotor can by floated and friction can be reduced through fluid lubrication when the lubricating oil pressure on the bearing surface becomes high (Figure 3, Figure 4 (a), (b)).