Jet siphon drainage device and bearing lubrication hydraulic system

The invention provides a jet siphon drainage device which comprises a sucked fluid inlet, a fluid outlet, a main runner communicating the sucked fluid inlet with the fluid outlet, a high-pressure fluid inlet, a high-pressure fluid outlet and an auxiliary runner communicating the high-pressure fluid inlet with the high-pressure fluid outlet. The main runner comprises an inflow section, an outflow section and a middle section for communicating the inflow section with the circulation section; the high-pressure fluid outlet is located in the inflow section and faces the fluid outlet. The invention provides a bearing lubrication hydraulic system which comprises an oil tank, a pumping pipeline used for pumping hydraulic oil in the oil tank to a bearing seat, an oil return pipe used for returning hydraulic oil in the bearing seat to the oil tank, and an injection siphon drainage device. A sucked fluid inlet of the jet siphon drainage device is connected with the oil return pipe, and a fluid outlet is connected with