CN115199594A

CN115199594A - Jet self-priming pump

Info

Publication number: CN115199594A
Application number: CN202210831150.1A
Authority: CN
Inventors: 郭荣; 张倚萌; 王乾年; 李舟睿; 张人会; 申正精
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2022-07-14
Filing date: 2022-07-14
Publication date: 2022-10-18

Abstract

The invention discloses a jet self-priming pump, which comprises a pump shell and an impeller, wherein the impeller is rotatably arranged on one side in the pump shell, a circulation cavity for jet circulation is arranged in the pump shell, a jet device assembly is arranged in the circulation cavity, the jet device assembly is provided with a jet pipe fixedly arranged in the pump shell, the jet pipe is arranged along the axis of the pump, the tail end of the jet pipe is opposite to the center of the impeller, the front end of the jet pipe is connected with a front guide pipe, an inducer is arranged in the front guide pipe, the inducer is provided with a shaft body, the outer wall of the shaft body is spirally and circularly provided with a plurality of spiral blades, and a driving shaft of the impeller penetrates through the jet pipe along the axis of the pump and extends into the front guide pipe to be connected with the shaft body of the inducer. Because the liquid on the hub side is pressed outwards under the action of centrifugal force, bubbles are pressed to be controlled at the local part of the outer edge and are condensed in the inducer, the whole central flow passage is not easy to be blocked, the overflowing effect is effectively enhanced, the cavitation allowance of the pump can be reduced, the cavitation resistance is improved, the pumping efficiency is improved, and the noise is reduced.

Description

Jet self-priming pump

Technical Field

The invention relates to the technical field of self-priming pumps, in particular to a jet flow self-priming pump.

Background

The self-sucking pump has the characteristics of high lift, convenience in starting, wide applicability, simplicity in operation and the like, and is widely applied to the occasions of industrial, agricultural, building, household water supply and the like. Compared with a self-priming centrifugal pump of a gas-liquid mixing type and the like, as shown in figure 1, the jet self-priming pump is characterized in that an impeller inlet pipeline is directly connected with a jet device, the jet device is integrally arranged in a pump body, the structure is simple and reliable, the self-priming performance is good, and meanwhile, the jet self-priming pump has the characteristics of convenience in installation and maintenance and the like, so that the jet self-priming pump is widely applied.

However, the central jet has the characteristics of small surface area of high-speed jet, large pressure drop of the injection pipe, short length, easy separation of flow and the like, so that the jet self-priming pump adopting the central jet device often has the problems of over-high lift at a closed dead point, narrow high-efficiency area, large-flow cavitation, steep lift and power curve (large slope) and the like, and particularly, when the jet self-priming pump operates under the working condition of large flow, the phenomena of cavitation, vibration, flow cutoff and the like are often easy to occur. In view of the above, we propose a jet self-priming pump to solve the above problems.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the technical defects and provide a novel anti-cavitation device which is reasonable in structure and good in anti-cavitation performance; energy loss is reduced, and the efficiency of the pump is improved; the jet self-priming pump has the advantages of noise reduction and good use effect.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: the utility model provides a efflux self priming pump, includes pump case, impeller, and the impeller rotates and sets up in the inside one side of pump case, and the inside circulation chamber that is used for the efflux circulation that is equipped with of pump case is equipped with ejector assembly in the circulation chamber, ejector assembly has the fixed injection pipe that sets up in the pump case, and the injection pipe sets up and its end is just to the impeller center along the axis of pump, and the connection of injection pipe front end is equipped with leading pipe, is equipped with the inducer in the leading pipe, the inducer has the axis body, and axis body outer wall spiral is around being equipped with multi-disc helical blade, the drive shaft of impeller passes the injection pipe along the axis of pump and extends to in the leading pipe and is connected with the axis body of inducer, through stator cavity intercommunication between the outer fringe export of impeller and the circulation chamber.

Furthermore, the ejector assembly further comprises an inlet structure, the inlet structure comprises an inlet cavity surrounding the preposed guide pipe and the jet pipe, an inlet pipe is arranged on the side wall of the pump shell in a penetrating mode, one end of the inlet pipe is connected with the water inlet end, and the other end of the inlet pipe is communicated with the inlet cavity.

Furthermore, a neck reducing section is arranged at one end of the preposed catheter close to the injection pipe.

Furthermore, the diameter of one side of the injection pipe, which is close to the inlet cavity, is smaller than the diameter of one side of the injection pipe, which is close to the impeller, so that a Venturi tube structure is formed.

Furthermore, helical blade encircles and sets up and be the circumference array at the axis body periphery and be equipped with three to helical blade keeps away from the flank width of necking down section and is less than the flank width that is close to necking down section.

Furthermore, the top of the circulation cavity is connected with a water outlet pipe, one side of the water outlet pipe is connected with a water injection hole, one side of the bottom of the circulation cavity is provided with a drain hole, and the water injection hole and the drain hole are screwed with a plug.

Compared with the prior art, the invention has the advantages that: the inducer is additionally arranged in the preposed guide pipe at the front end of the injection pipe, the inducer is driven to rotate by the rotation of the impeller, the inducer is an axial-flow impeller, when the inducer rotates, bubbles are generated at the outer edge of the inducer, and in the process of moving towards the rear side along the axial direction, the bubbles are controlled to be locally at the outer edge and are condensed in the inducer under the action of the outward pressure of liquid at the hub side under the action of centrifugal force, so that the whole central flow passage is not easy to be blocked, the overflowing effect is effectively enhanced, the cavitation allowance of the pump can be reduced, the cavitation resistance is improved, the pumping efficiency is improved, and the noise is reduced.

Drawings

Fig. 1 is a schematic diagram of a jet self-priming pump in the prior art.

Fig. 2 is a schematic structural diagram of a jet self-priming pump according to the present invention.

Fig. 3 is a schematic structural diagram of the inducer of the invention.

As shown in the figure: 1. a pump housing; 2. an impeller; 3. a circulation chamber; 4. an ejector assembly; 5. an injection pipe; 6. a pre-catheter; 7. an inducer; 8. a shaft body; 9. a helical blade; 10. a drive shaft; 11. a guide vane cavity; 12. an inlet chamber; 13. an inlet pipe; 14. a necking section; 15. a water outlet pipe; 16. a water injection hole; 17. and (4) draining the water.

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings. In which like parts are designated by like reference numerals.

In the description of the present invention, it is to be understood that the terms "center", "lateral", "upper", "lower", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified. Furthermore, the term "comprises" and any variations thereof are intended to cover non-exclusive inclusions.

A jet self-priming pump is shown in figure 1 and comprises a pump shell 1 and an impeller 2, wherein the impeller 2 is rotatably arranged on one side inside the pump shell 1, a circulation cavity 3 used for jet circulation is formed inside the pump shell 1, the impeller 2 is driven to operate through a motor, a jet device assembly 4 is arranged in the circulation cavity 3, the jet device assembly is provided with a jet pipe 5 fixedly arranged in the pump shell 1, the jet pipe 5 is arranged along the axis of the pump, the tail end of the jet pipe is right opposite to the center of the impeller 2, when the impeller 2 rotates, the center of the impeller 2 generates negative pressure to suck liquid in the jet pipe 5, and then the liquid is pressurized and thrown out from the outer edge of the impeller 2 through the rotation pressurization of the impeller 2.

The front end of the injection pipe 5 is connected with a preposed conduit 6, the inlet structure comprises an inlet cavity 12 surrounding between the preposed conduit 6 and the injection pipe 5, and the diameter of one side of the injection pipe 5 close to the inlet cavity 12 is smaller than that of one side close to the impeller 2 to form a Venturi tube structure. The outer edge outlet of the impeller 2 is communicated with the circulating cavity 3 through a guide vane cavity 11; the high-pressure high-speed liquid thrown out by pressurization enters the guide vane cavity 11, enters the circulation cavity 3 through the guide vane cavity 11, flows to the end of the preposed guide pipe 6 in a low-pressure area and is sucked into the injection pipe 5 through the preposed guide pipe 6 again, and a necking section 14 is arranged at one end, close to the injection pipe 5, of the preposed guide pipe 6. Because the injection pipe 5 is in a venturi tube structure, enough low pressure is formed at the inlet cavity 12 to suck the liquid connected with the inlet pipe 13 into the pump shell to form self-suction, so that a circulation of liquid flow is formed in the pump shell 1, the continuously circulated liquid flow forms negative pressure through the injection pipe 5 to suck the liquid from the inlet pipe 13 for supplement, and the water outlet pipe 15 can be opened to pump the liquid outwards when the liquid flow circulates. The jet device assembly 4 further comprises an inlet structure, an inlet pipe 13 is arranged on the side wall of the pump shell 1 in a penetrating mode, one end of the inlet pipe 13 is connected with a water inlet end, and the other end of the inlet pipe 13 is communicated with the inlet cavity 12. The top of the circulation cavity 3 is connected with a water outlet pipe 15, one side of the water outlet pipe 15 is connected with a water injection hole 16, one side of the bottom of the circulation cavity is provided with a water discharge hole 17, and the water injection hole 16 and the water discharge hole 17 are both screwed with screw plugs.

As an improvement, as shown in fig. 2 and 3, an inducer 7 is arranged in the front catheter 6, the inducer 7 has a shaft body 8, a plurality of helical blades 9 are spirally and circularly arranged on the outer wall of the shaft body 8, a driving shaft 10 of the impeller 2 extends into the front catheter 6 through the injection pipe 5 along the axis of the pump and is connected with the shaft body 8 of the inducer 7, in actual use, the impeller 2 rotates and drives the inducer 7 to rotate simultaneously through the driving shaft 10 which drives the impeller 2, the helical blades 9 are circularly arranged on the periphery of the shaft body 8 in a circumferential array, and the width of a side wing of the helical blade 9 far away from the necking section 14 is smaller than that of the side wing close to the necking section 14.

The jet self-priming pump comprises main flow passage components such as a jet device, a centrifugal impeller 2 and a guide vane cavity 11, wherein the jet device is arranged in front of an inlet of the impeller 2, the high-speed jet effect is realized by means of a jet device assembly 4, momentum and energy exchange between high-speed jet flow and inflow fluid is realized, and low pressure is formed at the inlet of the pump to realize self priming.

The invention adds a three-blade inducer 7 which is newly designed and matched with the original model impeller 2 in front of the ejector assembly 4, and the inducer is rotated by a driving shaft 10 which passes through the ejector pipe 5 as shown in figure 2.

The invention adds a three-blade inducer 7 in front of the nozzle of the ejector, belongs to an axial flow impeller 2, has the geometric characteristics and the cavitation characteristics of the axial flow impeller 2, and has no centrifugal force action for promoting the separation of liquid and bubbles like the centrifugal impeller 2. In the process of moving forward in the axial direction, the liquid on the hub side is pressed outward under the action of centrifugal force, so that the bubbles are pressed to the local part of the outer edge and condensed in the inducer 7, and therefore, the whole flow channel is not easy to be blocked. Its external characteristics are slow performance decrease during cavitation without obvious sudden decrease stage. The outer edge of the hollow bubble is compressed, so that the hollow bubble moves towards the outer edge along the axial direction and collapses after reaching a high-pressure area, thereby greatly limiting the development of the hollow bubble and avoiding the influence of cavitation erosion on the flow passage component. The lift generated by the inducer 7 reduces the cavitation allowance of the pump, improves the cavitation resistance of the pump, further improves the performance, improves the efficiency and reduces the noise.

The present invention and the embodiments thereof have been described above, and the description is not restrictive, and the embodiments shown in the detailed description are only a part of the embodiments of the present invention, not all embodiments, and the actual configuration is not limited thereto. In summary, those skilled in the art should be able to conceive of the present invention without creative design of the similar structural modes and embodiments without departing from the spirit of the present invention, and all such modifications should fall within the protection scope of the present invention.

Claims

1. The utility model provides a efflux self priming pump, includes pump case (1), impeller (2), and impeller (2) rotate to set up in the inside one side of pump case (1), its characterized in that, and pump case (1) is inside to be equipped with and to be used for the circulating chamber (3) of efflux circulation, is equipped with ejector assembly (4) in circulating chamber (3), ejector assembly has fixed injection pipe (5) of setting in pump case (1), and injection pipe (5) set up and its end is just to impeller (2) center along the axis of pump, and injection pipe (5) front end is connected and is equipped with leading pipe (6), is equipped with inducer (7) in leading pipe (6), inducer (7) have axis body (8), and axis body (8) outer wall spiral is around being equipped with multi-disc helical blade (9), drive shaft (10) of impeller (2) pass injection pipe (5) along the axis of pump and extend to and be connected with the axis body (8) of inducer (7) in leading pipe (6), through guide vane chamber (11) intercommunication between the outer fringe export of impeller (2) and circulating chamber (3).

2. The jet self-priming pump according to claim 1, wherein the jet assembly (4) further comprises an inlet structure, the inlet structure comprises an inlet cavity (12) surrounding between the front guide pipe (6) and the jet pipe (5), an inlet pipe (13) is arranged on the side wall of the pump shell (1) in a penetrating manner, one end of the inlet pipe (13) is connected with the water inlet end, and the other end of the inlet pipe is communicated with the inlet cavity (12).

3. A fluidic self-primer pump according to claim 2, characterized in that the end of the foreline (6) close to the ejector tube (5) is provided with a neck section (14).

4. A fluidic self-primer pump according to claim 2, characterized in that the diameter of the side of the ejector tube (5) close to the inlet chamber (12) is smaller than the diameter of the side close to the impeller (2) to form a venturi structure.

5. A fluidic self-primer pump according to claim 3, characterized in that the helical blade (9) is provided in three pieces in a circumferential array around the shaft body (8), and the width of the flank of the helical blade (9) away from the neck section (14) is smaller than the width of the flank close to the neck section (14).

6. The jet flow self-priming pump according to any one of the claims 1 to 5, wherein the top of the circulation cavity (3) is connected with a water outlet pipe (15), one side of the water outlet pipe (15) is connected with a water injection hole (16), one side of the bottom of the circulation cavity is provided with a water discharge hole (17), and the water injection hole (16) and the water discharge hole (17) are both screwed with plugs.