JPS5819879B2 - Self-priming turbine pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-priming turbine pump in which guide vanes are provided around an impeller.

In general, in self-priming turbine pumps, a mixed fluid of water and air flows out from inside the impeller into the air-water separation chamber, where it is separated into air and water.The air flows out from the pump outlet, and the water flows out again. It returns to the impeller and performs a self-priming action.

In order to effectively perform this action, a water return hole has conventionally been provided at the pump suction port, but this has the disadvantage that the water pumping characteristics are significantly reduced and the pump is less efficient when in use.

In recent years, a hole has been provided in the passage of the guide vane in the axial direction of the impeller to communicate the inside of the passage of the guide vane with the air-water separation chamber, and a part of the discharged water flows through this hole to reduce the pressure at the entrance of the passage. A technique has been proposed to improve self-priming performance by preventing water from rising and allowing water to circulate smoothly (see Japanese Utility Model Application No. 49-118802).

However, in this prior art, the influence of the self-priming flow circulating inside the impeller is limited to a certain range, and the balanced state of the impeller cannot be disturbed.

This is because some of the discharged water that flows in through the holes provided in the guide vanes passes through the passage of the guide vanes without flowing into the impeller.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a self-priming pump having a closed type impeller that can perform self-priming very efficiently by disrupting the balance of the impeller during self-priming operation, and that does not reduce the water pumping performance of the pump. - Provide pin pumps.

According to the present invention, the self-priming flow outlet facing the outer circumferential portion of the impeller and communicating the guide vane passage and the steam/water separation chamber is
The opening spans the guide vane inlet and the impeller outer periphery.

Therefore, the self-priming flow enters the outer periphery of the impeller, passes through the passage of the guide vanes, and then flows to the steam/water separation chamber.

This disrupts the balance inside the impeller, making it easier to release air bubbles remaining inside the impeller into the air-water separation chamber, improving self-priming performance.

In other words, a part of the self-priming working flow flowing out from the outlet easily enters the outer periphery of the impeller, so it circulates inside the impeller, resulting in extremely good self-priming performance. It is.

In addition, the outlet opening that spans the guide vane inlet and the impeller outer periphery is 1. It is possible to obtain a turbine pump with good self-priming performance and pump efficiency without disturbing the flow and therefore having no substantial effect on pump performance.

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2, 1 is an impeller of a turbine pump, 2 is an internal casing, and the internal casing 2 has guide vanes 11 at the radial outer circumference of the impeller 1.
is installed.

3 is a racket, and 4 is a pump casing.

During self-priming operation, a mixed flow of water and air passes from the water passage 5 in the impeller 1 to the water passage 10 at the guide vane 11, and is separated into water and air in the air-water separation chamber 6. Pump outlet (
(not shown), and the water returns to the impeller 1 again.

In the self-priming turbine pump embodying the present invention, a self-priming flow path 7 formed of a slit or a hole is bored in the side wall of the internal casing 2 .

The position of this passage 7 is near the outlet 8 of the impeller 1 as shown in the figure, that is, the lower outlet a of the passage 7 for the self-priming flow faces the outer circumference of the impeller 1, and the flow The channel 7 communicates with the guide vane channel 10 and the steam/water separation chamber 6.

That is, the output lower a is provided in the inner casing 2 so as to straddle the inlet of the guide vane 11 and the outer circumference of the impeller 1.

The number of flow paths 7 for the self-priming flow may be one, but it is preferable that the number is the same as the number of guide vanes.

Further, it is preferable that the radial position of the protruding lower part a is slightly to the left of the middle of the guide vane 11, as shown in FIG.

As a result, the self-priming working flow 9 passing through the flow path of the self-priming working flow, that is, the slit or the flow path 7, is transferred to the impeller 1 as shown in the figure.
The air flows into the inside of the impeller, causing an unbalanced state, and circulates inside the impeller, turning the air into bubbles.

The bubbled air is immediately removed through the passage of the guide vane 11, resulting in extremely efficient self-priming, and the flow is not disturbed even during pumping, so pump performance does not deteriorate.

That is, according to the present invention, the flow path for the self-priming working flow is provided facing the outer periphery of the impeller, and the passage of the guide vane is communicated with the steam/water separation chamber, which reduces pump performance. It is possible to obtain a self-priming turbine having a rosette type impeller with good self-priming performance without any problems.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a self-priming turbine pump according to the present invention;
FIG. 2 is a cross-sectional view of the guide vane. 1... Impeller, 2... Internal casing, 3... Bracket, 4... Pump casing, 5... Inside the impeller. Water passage, 6.
...Air-water separation chamber, 7a... Outlet of self-priming working flow, 8... Impeller outlet, 9... Water-suction working flow, 10... ...Guiding vane passage, 11...
...Guiding blade.

Claims (1)

[Claims] 1. In a self-priming turbine pump having a guide vane around a closed impeller, an outlet for the self-priming working flow that faces the outer periphery of the impeller and communicates the passage of the guide vane with the steam/water separation chamber. is a self-priming turbine pump characterized by having an opening spanning the guide vane inlet and the impeller outer periphery.