Self-priming centrifugal pump with automatic closing of return hole

Abstract

The invention discloses a self-absorption centrifugal pump with a water return hole capable of being closed automatically. According to the self-absorption centrifugal pump, a coaxial water return hole automatically-closing device is arranged right in front of the water return hole of the pump. The self-absorption centrifugal pump is mainly composed of a cylinder sleeve and a piston moving in the cylinder sleeve. When self-absorption is started by the pump, the piston resets under action of a compression spring; the water return hole is opened, and self-absorption water conveying is conducted; once the self-absorption process is completed, pressure water generated at an outlet of the pump enters a rear cavity of the piston through a pipe; and the piston is driven to advance to block the water return hole, and leakage is eliminated. The self-absorption centrifugal pump has the positive effects that self-absorption time of the pump is shortened; no leakage can be generated; volume losses are reduced; and efficiency of the pump is improved. To prevent the pressure water from damaging the structure, the piston drives a round bar to block the water return hole through the compression spring instead of direct blocking, and therefore if impurities such as sand grains are contained at a conical opening of the water return hole, the situation that leakproofness is lost due to damage of the conical opening can be avoided as a result of protection of the compression spring; and reliable and normal operation of the pump is guaranteed.

Description

technical field [0001] The invention relates to a centrifugal pump, in particular to a self-priming centrifugal pump whose return hole can be automatically closed. Background technique [0002] In the well-known common centrifugal pump, if the suction liquid level is below the impeller, it should be pre-filled with water when starting, which is very inconvenient. In order to store water in the pump, a bottom valve needs to be installed at the inlet of the suction pipe. When the pump is working, the bottom valve will cause a large hydraulic loss. The so-called self-priming pump means that it does not need to be irrigated before starting (it still needs to be irrigated for the first time after installation). After a short period of operation, the pump itself can suck up the water and put it into normal work. [0003] Due to the special structure of the pump body of the gas-liquid hybrid self-priming pump, after the pump stops, there is a certain amount of water in the pump bo...

AI Technical Summary

Problems solved by technology

[0006] However, there is a contradiction between "short self-priming and large leakage" in the size of the channel area of ​​the return hole, that is, the area of ​​the return hole is large, the flow of liquid is large, and the self-priming time is short, but after the self-priming process is completed, the return hole will cause Leakage and volume loss, the larger the area of ​​the return hole, the greater the leakage and the lower the efficiency of the pump

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