WO2023279689A1

WO2023279689A1 - Direct current permanent magnet self-priming composite shielding pump

Info

Publication number: WO2023279689A1
Application number: PCT/CN2022/070623
Authority: WO
Inventors: 陈荣国
Original assignee: 陈荣国
Priority date: 2021-07-05
Filing date: 2022-01-07
Publication date: 2023-01-12

Abstract

A direct current permanent magnet self-priming composite shielding pump, comprising a pump inlet (1), a gas-liquid mixing chamber (2) (or injector), a centrifugal terminal, a buffer boost chamber (7), a gas-liquid separation chamber (8) and a pump outlet (9). The pump inlet (1) is connected to an inlet of the gas-liquid mixing chamber (2) (or injector), an outlet of the gas-liquid mixing chamber (2) (or injector) is connected to an inlet of the centrifugal terminal, an outlet of the centrifugal terminal is in communication with an inlet of the buffer boost chamber (7), an outlet of the buffer boost chamber (7) is in communication with the gas-liquid separation chamber (8), and the gas-liquid separation chamber (8) is in communication with the pump outlet (9). The buffer boost chamber (7) is used for quickly decelerating and pressurizing a high-speed pressured fluid. In an exhaust and self-priming phase, the flow speed of the gas-liquid mixed fluid is lowered and bubble bursts are reduced at the same time. In a non-exhaust phase, the flow resistance is reduced, the pressure loss is lowered, and at the same time the fluid at the outlet of the centrifugal terminal is buffered and pressurized.

Description

DC permanent magnet self-priming compound canned pump

technical field

The invention relates to a self-priming compound canned pump, in particular to a DC permanent magnet self-priming compound canned pump, which belongs to the field of fluid machinery.

Background technique

As we all know, the canned pump is a fully static sealed structure, no risk of leakage, high reliability pump, its volume can be very small, and has the advantage of super quiet, widely used in many fields such as chemical industry, civil water supply and drainage, household appliances, etc. , especially in the transportation of precious, flammable, explosive, radioactive and corrosive fluid media, which play a key technical support role. Recently, there is a huge demand for wall-hung boilers and water heaters. The output value of these two fields in China is not fully counted. Has exceeded 2 billion. The canned pump has a unique structure, which can seal the motor and the pump body in a certain canned pump pump cavity, and the pumping medium is filled with the inner wall of the pump cavity. The overall structure has no moving seals, and the operation is safe. At the same time, the circulating medium can effectively solve the problem of motor temperature rise, without the need for motor cooling fans, and reduce the noise of shielded pumps. It has very strong product competitiveness in scenarios where there is a need for silence, such as household appliances and hospital testing instruments.

The canned pump is a non-moving sealed pump. The impeller of the canned pump is fixedly connected with the rotor of the canned motor and sealed in a canned pump chamber filled with the pumped medium. There is only a static seal in the pump body of the canned pump. The rotating magnetic field is provided by the wire winding and Drive the rotor. Even so, the vast majority of canned pumps do not have the self-priming function at present. In order to achieve self-priming, there are also technical solutions that directly adopt the existing jet pump injector structure and use a conventional asynchronous motor to drive the centrifugal impeller. However, most injector structures will lead to The efficiency of the self-priming canned pump is seriously reduced due to the lower energy conversion rate and the temperature rise of the asynchronous motor. In order to make up for the performance drop of the compound canned pump caused by the loss of efficiency, it is generally necessary to replace a larger-power motor and a larger-diameter impeller. , it is difficult to effectively promote in engineering. The current dilemma is how to improve the hydraulic efficiency of the canned pump while making it have the basic self-priming function and retain the original advantage of ultra-quietness.

Contents of the invention

In view of the problems that most of the existing canned pumps do not have self-priming or have weak suction and limited energy efficiency, the purpose of the present invention is to provide a pump with self-priming, outstanding performance in flow rate, head, suction, etc., strong safety, and compact structure. DC permanent magnet self-priming compound canned pump.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A composite canned pump in the present invention includes a pump inlet, a gas-liquid mixing chamber, a centrifugal end, a buffer pressurization chamber, a gas-liquid separation chamber and a pump outlet, the pump inlet is connected to the gas-liquid mixing chamber inlet, and the gas-liquid mixing chamber outlet is connected to the centrifugal The inlet of the pump end, the outlet of the centrifugal end are connected with the inlet of the buffer pressurization chamber, the outlet of the buffer pressurization chamber is connected with the gas-liquid separation chamber, and the gas-liquid separation chamber is connected with the pump outlet;

Another composite canned pump of the present invention includes a pump inlet, an injector, a centrifugal end, a buffer pressurization chamber, a gas-liquid separation chamber and a pump outlet. The pump inlet is connected to the injector inlet, and the diffuser section of the injector is connected to the centrifugal end inlet. The outlet of the centrifugal end communicates with the inlet of the buffer pressurization chamber, the outlet of the buffer pressurization chamber communicates with the gas-liquid separation chamber, and the gas-liquid separation chamber communicates with the pump outlet.

The centrifugal end specifically includes a DC permanent magnet motor, a centrifugal impeller and a centrifugal pressurized water chamber. The centrifugal impeller is located in the centrifugal pressurized water chamber and is connected to the rotor of the DC permanent magnet motor. The rotor of the DC permanent magnet motor is isolated from the stator through a shielding sleeve; The maximum speed of the DC permanent magnet motor reaches at least 3600 rpm;

The buffer pressurization chamber is used to quickly decelerate and pressurize the high-speed pressurized fluid at the outlet of the centrifugal end; in the exhaust and self-priming stage, reduce the flow rate of the gas-liquid mixed fluid while reducing bubble breakage; in the non-exhaust stage, reduce While the flow pressure loss is achieved, the buffer pressurization of the outlet fluid of the centrifugal end is realized.

The gas-liquid mixing chamber has a return hole, and communicates with the gas-liquid separation chamber through the return hole;

The injector communicates with the gas-liquid separation chamber through a nozzle.

The present invention also provides a combined self-priming compound canned pump, comprising a aforementioned self-priming compound canned pump and at least one centrifugal pump, the inlets of the self-priming compound canned pump and the centrifugal pump are connected in parallel, and combined The outlets of canned pumps and centrifugal pumps are connected in parallel.

By adopting above technical scheme, the beneficial effect that the present invention has is:

1. Compared with the traditional asynchronous motor with large impeller and injector, it can only solve the self-priming performance of the compound pump but cannot solve the disadvantages of efficiency. The DC permanent magnet motor is convenient for the intelligent control and performance monitoring of the compound shielded pump, and the high-speed centrifugal small impeller utilizes high-speed Cooperating with the form of DC motor, when the performance of the traditional composite canned pump is equal to that of the traditional composite canned pump, the overall power is small, and the operating efficiency is high. It improves the energy efficiency of the pump while taking into account performance and safety. It is easy to realize miniaturization and has a very high market value.

2. The use of DC permanent magnet motor combined with the characteristics of the gas-liquid mixing chamber and the canned pump makes the canned pump have the functions of strong self-priming, good hydraulic characteristics, energy saving and anti-cavitation, and the space position and internal structure of the buffer booster chamber are skillfully set , Effectively solve the technical problem that the gas-liquid separation is difficult due to the severe bubble breakage in the composite canned pump at high speed.

3. The structure of the buffer booster chamber is various, the material is convenient to obtain, and the cost ratio is low, but it can greatly improve the gas-liquid separation capacity in the pump and realize the strong self-priming performance of the canned pump.

4. Fixed or rotating guide vanes can be added to the buffer booster chamber, or the structure of the buffer booster chamber can be changed, and the inlet and outlet of the buffer chamber can be set as rotating guide vanes to further enhance the buffer booster effect.

5. The centrifugal end is equipped with a centrifugal impeller, a centrifugal pressure water chamber and a DC permanent magnet motor separately. According to different application requirements, by connecting one or more pumps in parallel at the pump inlet end, a self-priming composite pump with higher performance can be combined as required. Shielding pump.

6. The inlet of the return hole of the gas-liquid mixing chamber can be arranged with a check valve or an elastic stopper. During the self-priming working stage, the check valve or the elastic stopper is in the open state, and the liquid inside the gas-liquid separation chamber flows into the gas-liquid through the backflow hole. In the mixing chamber, the gas-liquid mixing process is completed here; during the working stage, the check valve or the elastic flap is closed, and the liquid in the gas-liquid separation chamber can no longer flow into the gas-liquid mixing chamber through the position of the return hole, which can further improve the working stage. efficiency.

7. A check valve or elastic stopper can be arranged at the inlet of the injector nozzle. During the self-priming working stage, the check valve or elastic stopper is in the open state, and the liquid inside the gas-liquid separation chamber flows into the diffuser section of the injector through the position of the injector nozzle. , where the gas-liquid mixing process is completed; during the working stage, the check valve or the elastic flap is closed, and the liquid in the gas-liquid separation chamber can no longer enter the injector through the nozzle position, which can further improve the energy efficiency of the working stage.

8. The composite canned pump of the present invention can balance the pump performance and the specific requirements of gas-liquid separation according to actual needs, and the number of the buffer booster chamber is not limited to one.

9. The structure of the self-priming centrifugal pump maintains the characteristics of the non-moving seal of the canned pump, and is suitable for pumping corrosive, toxic, harmful, and flammable media. At the same time, it adopts a low-voltage DC motor, which has extremely high safety.

10. The self-priming compound canned pump includes gas-liquid mixing chamber (or ejector), centrifugal impeller, centrifugal pressure water chamber, buffer pressurization chamber, gas-liquid separation chamber and other parts. It has compact structure, small volume, high integration, and clever combination The advantages of shielded pumps and gas-liquid mixing chambers (or injectors) can cover the needs of various civil pumps and industrial pumps.

Description of drawings

Fig. 1 is a schematic longitudinal sectional view of the composite canned pump structure of the first embodiment;

Fig. 2 is a sectional view of the partial structure of the composite canned pump of the first embodiment;

Fig. 3 is the overall schematic diagram of the compound canned pump of the first embodiment;

Figure 4a is a schematic cross-sectional view of the flow direction of the diversion cavity;

Figure 4b is a schematic diagram of a partial cross-section of the diversion chamber;

Fig. 5 is a schematic cross-sectional view of the primary buffer chamber of the buffer pressurization chamber with a series structure of porous laminates;

Fig. 6 is a schematic cross-sectional view of the secondary buffer chamber of the buffer pressurization chamber with a series structure of porous laminates;

Figure 7a is a schematic diagram of the structure of the buffer pressurization chamber filling medium as spherical particles;

Fig. 7b is a schematic diagram of the filling structure of the buffer pressurization chamber with wire mesh multi-void laminates;

Fig. 7c is a schematic diagram of a buffer booster cavity filled with irregular particles and multiple voids;

Fig. 8 is a schematic diagram of a partial cross-sectional structure of the gas-liquid mixing chamber of the composite pump in the first embodiment;

Fig. 9a is a schematic diagram of the structure of the centrifugal end of the first embodiment;

Fig. 9b is a schematic structural diagram of the DC permanent magnet motor of the first embodiment;

Fig. 10 is a schematic flow diagram of the self-priming stage of the compound canned pump of the first embodiment;

Fig. 11 is a flow schematic diagram of the working stage of the composite canned pump of the first embodiment;

Fig. 12 is a schematic structural diagram of the open state of the check valve at the inlet of the return hole of the gas-liquid mixing chamber;

Fig. 13 is a schematic structural diagram of the closed state of the check valve at the inlet of the return hole of the gas-liquid mixing chamber;

Fig. 14 is a schematic structural diagram of the opening state of the non-return elastic flap at the inlet of the return hole of the gas-liquid mixing chamber;

Fig. 15 is a schematic structural diagram of the closed state of the non-return elastic flap at the inlet of the return hole of the gas-liquid mixing chamber;

Fig. 16 is a schematic diagram of the concentric distribution of the buffer pressurization chamber and the centrifugal end in the first embodiment;

Fig. 17 is a schematic diagram of the internal flow when the buffer pressurization chamber and the centrifugal end are concentrically distributed in the first embodiment;

Fig. 18 is a schematic diagram of the parallel structure of the composite canned pump and the centrifugal pump;

Fig. 19 is a schematic longitudinal sectional view of the composite canned pump structure of the second embodiment;

Fig. 20 is a cross-sectional view of the partial structure of the compound canned pump of the second embodiment;

Fig. 21 is the overall schematic diagram of the compound canned pump of the second embodiment;

Fig. 22 is a schematic diagram of the longitudinal sectional structure of the composite pump injector of the second embodiment;

Fig. 23a is a schematic diagram of the structure of the centrifugal end of the second embodiment;

Fig. 23b is a schematic structural diagram of the DC permanent magnet motor of the second embodiment;

Fig. 24 is a schematic flow diagram of the self-priming stage of the compound canned pump of the second embodiment;

Fig. 25 is a flow schematic diagram of the second embodiment of the compound canned pump working stage;

Fig. 26 is a schematic structural diagram of the open state of the injector nozzle inlet check valve;

Fig. 27 is a schematic structural diagram of the closed state of the injector nozzle inlet check valve;

Fig. 28 is a schematic structural diagram of the opening state of the non-return elastic flap at the inlet of the injector nozzle;

Fig. 29 is a schematic structural diagram of the closed state of the non-return elastic flap at the inlet of the injector nozzle;

Fig. 30 is a schematic diagram of the concentric distribution of the buffer pressurization chamber and the centrifugal end in the second embodiment;

Fig. 31 is a schematic diagram of the internal flow when the buffer pressurization chamber and the centrifugal end are concentrically distributed in the second embodiment.

detailed description

In order to enable those skilled in the art to better understand the technical solution in the present invention, the technical solution in the invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention, and what is obviously described is only a part of the present invention Examples, not all examples. Based on the embodiments of the invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the invention.

The present invention adopts a DC permanent magnet motor to reduce the overall size of the pump body by greatly reducing the centrifugal impeller and increasing the rotational speed of the motor, while ensuring that the overall performance of the pump meets the needs of practical applications. The reasonable configuration of the gas-liquid mixing chamber (or injector) and the buffer pressurization chamber realizes the self-priming function of the composite canned pump and obtains higher hydraulic efficiency. At the same time, compared with the traditional asynchronous motor, the DC permanent magnet motor has extremely high safety, even if there is an electric leakage, it will not cause fatal harm to the human body; the composite shielded pump of the present invention can self-prime, the overall size is small, and the structure is compact, and has outstanding product advantages. Market prospects.

A composite canned pump of the present invention comprises a pump inlet, a gas-liquid mixing chamber, a centrifugal end, a buffer pressurization chamber, a gas-liquid separation chamber and a pump outlet; the gas-liquid mixing chamber consists of a gas-liquid mixing chamber inlet, a gas-liquid mixing chamber, The return hole and the outlet of the gas-liquid mixing chamber are composed of a check valve or an elastic baffle at the position of the return hole; the centrifugal end specifically includes a centrifugal impeller, a centrifugal guide vane, a centrifugal pressure water chamber, a DC permanent magnet motor, and the DC permanent magnet The maximum speed of the motor is at least 3600 rpm; the inlet of the pump is connected to the inlet of the gas-liquid mixing chamber, the outlet of the gas-liquid mixing chamber is connected to the inlet of the centrifugal end, the outlet of the centrifugal end is connected to the inlet of the buffer booster chamber, and the outlet of the buffer booster chamber is connected to the gas-liquid The separation chamber is connected, and the gas-liquid separation chamber is connected with the pump outlet; the centrifugal impeller is connected with the motor rotor, and the motor rotor and the stator are separated by a shielding sleeve, and the pump as a whole has no dynamic seal.

Another composite canned pump of the present invention comprises a pump inlet, injector, centrifugal end, buffer pressurization chamber, gas-liquid separation chamber and pump outlet; injector is made up of injector inlet, conduit, nozzle, throat and diffusion section, A check valve or elastic baffle can be added to the nozzle inlet of the injector; the centrifugal end specifically includes a centrifugal impeller, a centrifugal guide vane, a centrifugal pressure water chamber and a DC permanent magnet motor, and the maximum speed of the DC permanent magnet motor can reach at least 3600 rpm The inlet of the pump is connected to the inlet of the injector located in the gas-liquid separation chamber, the diffuser section of the injector is connected to the inlet of the centrifugal end, the outlet of the centrifugal end is connected to the inlet of the buffer booster chamber, and the outlet of the buffer booster chamber is connected to the gas-liquid separation chamber. The liquid separation chamber is connected with the pump outlet; the centrifugal impeller is connected with the motor rotor, and the motor rotor and the stator are separated by a shielding sleeve, and the pump as a whole has no dynamic seal.

The buffer pressurization chamber is a channel for rapidly decelerating and pressurizing the high-speed pressurized fluid at the outlet of the centrifugal end, effectively reducing the flow velocity of the gas-liquid mixed fluid in the exhaust self-priming stage and reducing bubble breakage, while in the non-exhaust The stages effectively reduce the flow resistance and reduce the pressure loss, and at the same time realize the buffering and pressurization of the fluid at the outlet of the centrifugal end.

The buffer pressurization chamber is relatively independent from the gas-liquid separation chamber, and only the outlet of the buffer pressurization chamber is connected to the gas-liquid separation chamber.

The outlet of the buffer booster chamber can be distributed in various ways such as circumferentially, radially, or in a certain space area, and there is no less than one outlet.

The buffer booster chamber can be a series structure of porous laminates, an irregular porous plane, a porous space structure, a porous medium filling structure, a single or a combination of multiple circuitous flow channels, etc., which can simultaneously reduce bubble breakage and Efficient buffering of pressurized runners.

Fixed or rotating guide vanes can be added in the buffer booster chamber of the series structure of porous laminates, or the inlet and outlet of the buffer booster chamber can be set as rotatable guide vanes.

The buffer pressurization chamber and the centrifugal impeller are arranged vertically or concentrically. When distributed up and down, the outlet of the centrifugal end communicates with the buffer booster chamber through the diversion chamber.

The DC permanent magnet motor mainly includes a shielding sleeve, a stator, a rotor, and a motor shaft. The shielding sleeve isolates the rotor and the stator of the motor through static sealing, and the rotor and the impeller run directly in the working medium.

A check valve or an elastic flap can be arranged at the inlet of the gas-liquid mixing chamber return hole. When the self-priming phase of the compound canned pump is over, the check valve is closed under the drive of the pressure difference between the inside and outside of the gas-liquid mixing chamber, and the gas-liquid separation chamber The liquid can no longer enter the gas-liquid mixing chamber through the position of the return hole, the circulating flow in the pump is cut off, and the efficiency is improved.

A check valve or elastic stopper can be arranged at the inlet of the injector nozzle. When the self-priming stage of the composite canned pump is over, the check valve is closed under the drive of the pressure difference between the inside and outside of the injector, and the liquid in the gas-liquid separation chamber can no longer pass through. The position of the nozzle enters the interior of the injector, the circulating flow in the pump is cut off, and the efficiency is improved.

There is at least one buffer pressurization chamber, at least one centrifugal end, and at least one centrifugal end outlet.

The inlet of the gas-liquid mixing chamber can be connected to one or more pump inlets at the same time to form a parallel pump group, which does not affect the exhaust during the self-priming and exhausting stage, and improves the performance of the pump during the non-self-priming normal working stage to meet different application requirements .

The working process of compound canned pump:

When the self-priming compound canned pump is in the self-priming and exhausting stage, the pump and the driving motor are sealed in a compound canned pump chamber filled with the pumped medium. The gas-liquid mixing chamber (or ejector), centrifugal end, and flow guide The prefilled fluid is stored in the cavity, the buffer pressurization cavity and the gas-liquid separation chamber. The invention adopts a DC permanent magnet motor with higher safety and efficiency. Compared with the traditional asynchronous motor, although the DC permanent magnet motor drives the fluid to obtain a higher-speed working fluid, when the centrifugal impeller and the pump cavity are both reduced, the The gas-liquid separation of the compound canned pump is more difficult in the self-priming stage, which can easily lead to air binding of the high-speed impeller, so it is difficult to realize the self-priming function of the compound canned pump. Specifically, on the one hand, it is because the air bubbles are easily collided with the wall or the impeller in the high-speed flow state and are broken, and then cannot freely float up and leave the water body in the pump; on the other hand, the high-speed rotating impeller forms a very strong circle. The air bubbles are more likely to be broken in the direction of shearing. Due to the sharp reduction in the size of the air bubbles and the clamping of the high-speed flow in the pump, it is more difficult for the air bubbles to float up and leave the water body, resulting in almost failure of the gas-liquid separation, and the composite canned pump cannot be successfully completed. Self-priming. Therefore, in order to avoid the problem of gas-liquid separation caused by the high speed of the DC permanent magnet motor, the mixed fluid in the gas-liquid mixing chamber (or injector) is driven by the centrifugal impeller to do work at high speed, and then firstly drained by the centrifugal pressure water chamber into the The buffer pressurization chamber performs buffer pressurization, so that the air bubbles in the pump in the self-priming stage have a longer free floating time to complete the gas-liquid separation.

For the buffer pressurization chamber with a series structure of porous double-layer plates, a certain arrangement of buffer fins is arranged, and the high-speed fluid is guided by the buffer fins of the primary buffer chamber, and the speed decreases rapidly and is discharged from the outlet of the primary buffer chamber and flows into the secondary buffer chamber. In the secondary buffer chamber, the fluid medium is further decelerated and discharged through the outlet of the secondary buffer chamber. After the secondary stage, it enters the gas-liquid separation chamber or enters the next-stage buffer pressurization chamber. The kinetic energy obtained from the drive of the high-speed centrifugal impeller is effectively converted into potential energy through multi-stage buffering, and the deceleration and pressurization of the working medium is completed, reducing hydraulic loss and meeting the needs of gas-liquid separation.

The fluid flowing out of the outlet of the buffer pressurization chamber directly enters the gas-liquid separation chamber, and the velocity of the fluid medium in the gas-liquid separation chamber is significantly reduced due to the effect of diversion and buffer pressurization chamber, and the working fluid is fully retained in the gas-liquid separation chamber, realizing the compound pump gas-liquid separation. If there is no buffer chamber, the high-speed fluid behind the centrifugal impeller driven by the DC permanent magnet motor cannot be fully decelerated, resulting in the inability to complete the gas-liquid separation, and the impeller gas binding phenomenon will dominate, which will directly cause self-priming failure.

At the same time, in order to keep the structure of the composite canned pump compact and have a good buffer effect, the secondary buffer chamber and the primary buffer chamber of the buffer booster chamber can be kept concentric, and the outlet of the secondary buffer chamber is along the circumferential direction, radial direction or the cover of the secondary buffer chamber Distribution (uniform or non-uniform) in a certain area of the board. At the same time, the buffer pressurization chamber and the centrifugal end can be kept concentrically distributed, which can effectively improve the compactness of the overall structure.

When the self-priming composite shielded pump is in the actual working stage, the fluid to be pumped in the pump inlet pipeline flows into the gas-liquid mixing chamber along the composite pump inlet, and the high-speed working fluid that returns to the return hole is mixed with the gas-liquid mixing chamber and then enters the centrifugal end ( Or the fluid to be pumped in the pump inlet pipeline is sucked into the injector along the composite pump inlet, and the high-speed working fluid ejected from the nozzle is accelerated and mixed through the injector throat, and the diffusion section is decelerated and pressurized, and then enters the centrifugal end); then, this part After the fluid is accelerated and pressurized by the centrifugal impeller, it obtains a higher speed and pressure, and then it is discharged from the centrifugal pressure water chamber into the buffer pressurization chamber for deceleration and pressurization, and then discharged from the outlet of the buffer pressurization chamber to realize the deceleration and increase of the working medium. pressure.

The fluid flowing out from the buffer pressurization chamber enters the gas-liquid separation chamber, and part of the fluid is discharged through the outlet of the compound pump to complete the pumping of the fluid; the other part of the pressurized fluid that has not been discharged from the pump continues to circulate in the gas-liquid separation chamber to provide gas The return hole (or injector nozzle) of the liquid mixing chamber provides the working fluid, which is driven to work by the centrifugal end again, and the above process is repeated to realize the normal pumping of the fluid to be pumped by the composite canned pump. In this process, the buffer pressurization chamber is required to effectively reduce the flow resistance and reduce the pressure loss, and at the same time realize the buffer pressurization of the fluid at the outlet of the centrifugal end (the fluid with too high speed passes through the buffer pressurization chamber, and the kinetic energy is converted into pressure potential energy. If If there is no buffer pressurized chamber, energy will be dissipated due to strong impact, and the flow resistance can be reduced by reducing the speed, that is, energy dissipation).

As an improvement, check valves or elastic baffles can be arranged at the position of the return hole of the gas-liquid mixing chamber. When the self-priming working phase starts, only the prefilled fluid circulates in the pump, and there is no continuous replenishment of the fluid to be pumped. The pressure difference on both sides of the return valve or elastic retainer (inside the gas-liquid mixing chamber and the gas-liquid separation chamber) is small, and the check valve or elastic retainer is in an open state under the action of spring force, elastic force of the elastic retainer or electromagnetic force, and the gas-liquid The liquid inside the separation chamber flows into the gas-liquid mixing chamber through the position of the return hole, where the gas-liquid mixing process is completed; as the self-priming stage progresses, the pre-filling fluid in the pump is driven by the centrifugal impeller to do work, and the buffer structure decelerates and pressurizes. The pressure difference between the two sides of the structure such as the check valve or the elastic retainer increases continuously until the end of the self-priming stage, and the check valve overcomes the spring force or the electromagnetic force under the action of the large pressure difference and enters the closed state; at this time, The liquid in the gas-liquid separation chamber can no longer enter the gas-liquid mixing chamber through the position of the return hole, and the internal circulation of the fluid in the pump stops. In the self-priming stage, the disturbance of the fluid at the inlet by the high-speed centrifugal impeller destabilizes the pre-filled fluid interface in the gas-liquid mixing chamber, which effectively entrains the gas in the gas-liquid mixing chamber, and then this part of the gas-liquid mixture The fluid enters the inlet of the centrifugal end under the traction of the high-speed centrifugal impeller, and is boosted and accelerated by the centrifugal impeller, decelerated and pressurized by the buffer booster chamber, and the gas-liquid separation is completed after the gas-liquid separation is completed to realize the self-priming function of the composite canned pump; during the working stage, the gas The liquid in the liquid separation chamber no longer flows back to the position of the return hole, and the liquid that has done work is directly discharged through the outlet of the composite canned pump. By using the "open" or "cut-off" of the working fluid in the return hole, the self-priming function is realized and the internal circulation in the actual working stage is stopped, thereby effectively improving the hydraulic efficiency of the pump.

As an improvement, a check valve or elastic baffle can be arranged at the inlet of the injector nozzle. When the self-priming phase starts, only the prefilled fluid circulates in the pump without continuous replenishment of the fluid to be pumped. The pressure difference on both sides of the valve or the elastic flap (inside the injector and the gas-liquid separation chamber) is small, and the check valve or the elastic flap is in an open state under the action of the spring force, the elastic force of the elastic flap, or the electromagnetic force, and the inside of the gas-liquid separation chamber The liquid flows into the throat of the injector through the position of the injector nozzle, where the gas-liquid mixing process is completed; as the self-priming stage progresses, the pre-filling fluid in the pump is accelerated and pressurized through the injector, driven by the centrifugal impeller to do work, and the buffer structure decelerates and pressurizes With the continuous action of the process, the pressure difference between the two sides of the check valve or the elastic retainer will continue to increase until the end of the self-priming stage, and the check valve will overcome the spring force or electromagnetic force under the action of the large pressure difference and enter the closed state . At this time, the liquid in the gas-liquid separation chamber can no longer enter the injector through the nozzle position, and the internal circulation of the fluid in the pump stops. In the self-priming stage, the high-speed fluid flowing in from the nozzle and the strong negative pressure caused by the diffuser section form an effective entrainment effect on the gas in the conduit, and under the action of the buffer structure, the fluid decelerates and pressurizes to complete the gas-liquid separation to realize the compound canned pump Self-priming function; during the working stage, the liquid in the gas-liquid separation chamber no longer flows back to the nozzle position, and the liquid that has done work is directly discharged through the outlet of the compound shielded pump. By using the "open" or "cut-off" of the working fluid at the nozzle inlet, the self-priming function is realized while the internal circulation in the actual working stage is stopped, thereby effectively improving the hydraulic efficiency of the pump.

The present invention adopts a DC permanent magnet high-speed motor, and because of its high speed, a small-sized DC motor is used to drive a smaller centrifugal impeller. The overall size of the pump body is small, and the DC permanent magnet motor greatly improves the efficiency of conventional asynchronous motors. The maximum speed is above 3600rpm, even up to 10000rpm), with the design of the gas-liquid mixing chamber, diversion and buffer structure, it can realize the self-priming function of the compound canned pump and obtain higher hydraulic efficiency at the same time. At the same time, compared with the traditional asynchronous motor, the DC permanent magnet motor has extremely high safety. When the DC safety voltage of 36V and below is used, even if there is an electric leakage, there is no life threat to the human body. The overall size of the composite canned pump is small, the structure is compact, and it has Broad market application prospects.

The present invention will be further described below in conjunction with accompanying drawing and embodiment:

As shown in Figure 1, Figure 2 and Figure 3, this embodiment includes a pump inlet 1, a gas-liquid mixing chamber 2, a centrifugal end, a diversion chamber 6, a buffer pressurization chamber 7, a gas-liquid separation chamber 8, and a composite canned pump casing 10 and the pump outlet 9, the gas-liquid mixing chamber is composed of the gas-liquid mixing chamber inlet 201, the gas-liquid mixing chamber 202, the return hole 203 and the gas-liquid mixing chamber outlet 204 (Fig. 8), the centrifugal end specifically includes the centrifugal impeller 3, the centrifugal pressure Water chamber 11, DC permanent magnet motor 5 (as shown in Figure 9a and Figure 9b), wherein the DC permanent magnet motor rotor 503 is isolated from the stator 502 through the shielding sleeve 501, and the motor rotor 503 is fixedly connected to the centrifugal impeller 3 through the motor shaft 504, The DC permanent magnet motor has its own motor housing 505, and the pump body has no dynamic seal. The inlet of the pump is connected to the inlet of the gas-liquid mixing chamber, the outlet of the gas-liquid mixing chamber is connected to the inlet of the centrifugal end, the outlet of the centrifugal end is connected to the inlet of the buffer booster chamber, the outlet of the buffer booster chamber is connected to the gas-liquid separation chamber, and the gas-liquid separation chamber is connected to the pump outlet. The buffer pressurization chamber and the centrifugal impeller are distributed up and down or concentrically (Fig. 16). When distributed up and down, the outlet of the centrifugal end is connected to the buffer booster chamber through the diversion chamber.

As shown in Figure 4a and Figure 4b, the diversion cavity 6 includes a diversion cavity bottom plate 6-1, a diversion chamber 6-2, and a diversion cavity coaming plate 6-3; as shown in Figure 5, the porous laminates are connected in series The buffer pressurization chamber of the structure includes a primary buffer chamber 7-1 and a secondary buffer chamber 7-2, and the primary buffer chamber includes a primary buffer chamber inlet 7-100, a buffer fin 7-101, a primary buffer bottom plate 7-102, and a primary buffer chamber. Buffer chamber outlet 7-103, primary buffer chamber outlet cover plate 7-104 and primary buffer chamber 7-105; secondary buffer chamber 7-2 includes secondary buffer chamber 7-201, secondary buffer chamber cover plate 7- 202 and the secondary buffer cavity outlet 7-203 (shown in Figure 6).

As shown in Figure 7, the buffer pressurization chamber can have a variety of porous medium filling structures, which are used to effectively reduce the fluid flow rate and achieve the effect of fluid pressurization. Figure 7a shows that the filling medium is spherical particles, and Figure 7b shows that the filling medium is in the shape of a wire mesh The multi-void laminate filling structure, Fig. 7c shows the multi-void filling structure of irregular particles.

When the self-priming compound canned pump is in the self-priming and exhausting stage, the pump and the driving motor are sealed in a compound canned pump chamber filled with the pumped medium. The gas-liquid mixing chamber, centrifugal end, diversion chamber, buffer booster The chamber and the gas-liquid separation chamber store prefilled fluid. This embodiment uses a DC permanent magnet motor with higher safety and efficiency. Compared with the traditional asynchronous motor, although the DC permanent magnet motor drives the fluid to obtain a higher-speed working fluid, it makes the gas-liquid separation of the compound canned pump more difficult and extremely easy. As a result, the high-speed impeller is gas-bound, and the self-priming function of the composite canned pump cannot be realized.

Therefore, as shown in Figure 10, in order to avoid the problem of gas-liquid separation caused by the high speed of the motor, the mixed fluid in the gas-liquid mixing chamber is driven by the high-speed centrifugal impeller, and is first led out by the centrifugal pressure water chamber to enter the buffer pressurization The cavity is buffered and pressurized, so that the air bubbles in the pump in the self-priming stage have a longer free floating time to complete the gas-liquid separation. For the buffer pressurization chamber with a series structure of porous double-layer plates, a certain arrangement of buffer fins is arranged, and the high-speed fluid is guided by the buffer fins of the primary buffer chamber, and the speed decreases rapidly and is discharged from the outlet of the primary buffer chamber and flows into the secondary buffer chamber. In the secondary buffer chamber, the fluid medium is further decelerated and discharged through the outlet of the secondary buffer chamber. After the secondary stage, it enters the gas-liquid separation chamber or enters the next-stage buffer pressurization chamber. The kinetic energy obtained from the drive of the high-speed centrifugal impeller is effectively converted into potential energy through multi-stage buffering, and the deceleration and pressurization of the working medium is completed, reducing hydraulic loss and meeting the needs of gas-liquid separation.

The fluid flowing out of the outlet of the buffer pressurization chamber directly enters the gas-liquid separation chamber, and the velocity of the fluid medium in the gas-liquid separation chamber is significantly reduced due to the effect of diversion and buffer pressurization chamber, and the working fluid is fully retained in the gas-liquid separation chamber, realizing the compound pump gas-liquid separation. If there is no buffer chamber, the high-speed fluid behind the centrifugal impeller driven by the DC permanent magnet motor cannot be fully decelerated, resulting in the inability to complete the gas-liquid separation, and the impeller gas binding phenomenon will dominate, which will directly cause self-priming failure. At the same time, in order to keep the structure of the composite canned pump compact and have a good buffer effect, the secondary buffer chamber and the primary buffer chamber of the buffer booster chamber can be kept concentric, and the outlet of the secondary buffer chamber is along the circumferential, radial or secondary buffer chamber The cover plate is distributed (uniformly or non-uniformly) in a certain area. In addition, the buffer pressurization chamber and the centrifugal end can be kept concentrically distributed (as shown in FIG. 16 ), which can effectively improve the compactness of the overall structure.

When the self-priming compound canned pump is in the actual working stage, as shown in Figure 11 and Figure 17, the flow diagram of the compound canned pump in the working stage, the fluid to be pumped in the pump inlet pipeline is sucked into the gas-liquid mixing chamber along the compound pump inlet, and the backflow The high-speed working fluid returned by the hole enters the centrifugal end after being mixed with the gas-liquid mixing chamber; then, this part of the fluid is accelerated and pressurized by the centrifugal impeller to obtain a higher speed and pressure, and then discharged from the centrifugal pressure water chamber into the buffer pressurization chamber It decelerates and pressurizes, and discharges from the outlet of the buffer pressurization chamber to realize the deceleration and pressurization of the working medium. The fluid flowing out from the buffer pressurization chamber enters the gas-liquid separation chamber, and part of the fluid is discharged through the outlet of the compound pump to complete the pumping of the fluid; the other part of the pressurized fluid that has not been discharged from the pump continues to circulate in the gas-liquid separation chamber to provide gas The return hole of the liquid mixing chamber provides the working fluid. The liquid level inside the gas-liquid mixing chamber continues to be unstable, and the fluid to be pumped in the pump inlet is continuously entrained into the inlet of the centrifugal end. Repeat the above process to realize the normal operation of the compound canned pump for the pumped fluid. pumping. In this process, the buffer pressurization chamber is required to effectively reduce the flow resistance and reduce the pressure loss, and at the same time realize the buffer pressurization of the fluid at the outlet of the centrifugal end.

As shown in Figure 12 and Figure 14, a check valve 12 or an elastic stopper 13 can be arranged at the position of the return hole of the gas-liquid mixing chamber. Continuous replenishment of fluid, the pressure difference between the two sides of the check valve or elastic retainer (inside the gas-liquid mixing chamber and the gas-liquid separation chamber) is small, and the check valve or elastic retainer is under the action of spring elasticity, elastic retainer elastic force or electromagnetic force In the open state, the liquid inside the gas-liquid separation chamber flows into the gas-liquid mixing chamber through the position of the return hole, where the gas-liquid mixing process is completed; as the self-priming stage progresses, the pre-filling fluid in the pump is driven by the centrifugal impeller to do work, and the buffer structure decelerates With the continuous effect of pressurization and other processes, the pressure difference between the two sides of the structure such as the check valve or the elastic retainer will continue to increase until the end of the self-priming stage. Closed state; as shown in Figure 13 and Figure 15, the check valve or the elastic flap is in the closed state. At this time, the liquid in the gas-liquid separation chamber can no longer enter the gas-liquid mixing chamber through the position of the return hole, and the internal circulation of the fluid in the pump stop. In the self-priming stage, the disturbance of the fluid at the inlet by the high-speed centrifugal impeller destabilizes the pre-filled fluid interface in the gas-liquid mixing chamber, which effectively entrains the gas in the gas-liquid mixing chamber, and then this part of the gas-liquid mixture The fluid enters the inlet of the centrifugal end under the traction of the high-speed centrifugal impeller, and is boosted and accelerated by the centrifugal impeller, decelerated and pressurized by the buffer booster chamber, and the gas-liquid separation is completed after the gas-liquid separation is completed to realize the self-priming function of the composite canned pump; during the working stage, the gas The liquid in the liquid separation chamber no longer flows back to the position of the return hole, and the liquid that has done work is directly discharged through the outlet of the composite canned pump. By using the "open" or "cut-off" of the working fluid in the return hole, the self-priming function is realized and the internal circulation in the actual working stage is stopped, thereby effectively improving the hydraulic efficiency of the pump.

As shown in FIG. 18 , the self-priming compound canned pump of the present invention can also form a parallel pump group 20 with a single centrifugal pump. The self-priming composite canned pump 203 and the centrifugal pump 206 share the pump group inlet 201 and the pump group outlet 202, that is, the pump group inlet 201 is respectively connected to the self-priming composite canned pump inlet 204 and the centrifugal pump inlet 207; the self-priming composite canned pump outlet 205 and the centrifugal pump outlet 208 are connected to the pump group outlet 202 respectively. The pump set does not affect the exhaust during the self-priming and exhausting stage, and improves the performance of the pump during the non-self-priming normal working stage to meet different application requirements.

As shown in Figure 19, Figure 20 and Figure 21, this embodiment specifically includes a pump inlet 1, an injector, a centrifugal end, a diversion chamber 10, a buffer pressurization chamber 11, a gas-liquid separation chamber 12, a composite canned pump casing 14 and The pump outlet 13, the ejector is composed of the ejector inlet 2, the conduit 3, the nozzle 4, the throat pipe 5 and the diffuser section 6 (as shown in Figure 22), and the centrifugal end specifically includes the centrifugal impeller 7, the centrifugal guide vane 8, and the centrifugal pressure water chamber 15 1. DC permanent magnet motor 9 (as shown in Figure 23a and Figure 23b), wherein the motor rotor 93 is isolated from the stator 92 through the shielding sleeve 91, the motor rotor 93 is fixedly connected with the centrifugal impeller 7 through the motor shaft 94, and the DC permanent magnet motor comes with Motor housing 95, the pump body has no dynamic seal. The inlet of the pump is connected to the inlet of the injector, the diffusion section of the injector is connected to the inlet of the centrifugal end, the outlet of the centrifugal end is connected to the inlet of the buffer booster chamber, the outlet of the buffer booster chamber is connected to the gas-liquid separation chamber, and the gas-liquid separation chamber is connected to the pump outlet Pass. The buffer pressurization chamber and the centrifugal impeller are distributed up and down or concentrically. When distributed up and down, the outlet of the centrifugal end is connected to the buffer booster chamber through the diversion chamber.

When the self-priming compound canned pump is in the self-priming and exhausting stage, the pump and the DC permanent magnet motor are sealed in a compound canned pump chamber filled with the pumped medium, and the ejector, centrifugal end, diversion chamber, buffer booster The chamber and the gas-liquid separation chamber store prefilled fluid. This embodiment uses a DC permanent magnet motor with higher safety and efficiency. Compared with the traditional asynchronous motor, although the DC permanent magnet motor drives the fluid to obtain a higher-speed working fluid, it makes the gas-liquid separation of the compound canned pump more difficult and extremely easy. As a result, the high-speed impeller is gas-bound, and the self-priming function of the composite canned pump cannot be realized.

Therefore, as shown in Figure 24, in order to avoid the problem of gas-liquid separation caused by the high speed of the DC permanent magnet motor, the fluid mixed in the injector is driven by the centrifugal impeller at high speed, and then firstly drained by the centrifugal pressure water chamber and led out through the guide chamber After that, it enters the buffer pressurization chamber for buffer pressurization, so that the air bubbles in the pump in the self-priming stage have a longer free floating time to complete the gas-liquid separation. For the buffer pressurization chamber with a series structure of porous double-layer plates, a certain arrangement of buffer fins is arranged, and the high-speed fluid is guided by the buffer fins of the primary buffer chamber, and the speed decreases rapidly and is discharged from the outlet of the primary buffer chamber and flows into the secondary buffer chamber. In the secondary buffer chamber, the fluid medium is further decelerated and discharged through the outlet of the secondary buffer chamber. Then enter the gas-liquid separation chamber or enter the next stage buffer pressurization chamber. In this way, the kinetic energy obtained by the fluid driven by the high-speed centrifugal impeller can be effectively converted into potential energy through multi-stage buffering, so as to complete the deceleration and pressurization of the working medium, reduce hydraulic loss and meet the needs of gas-liquid separation.

The fluid flowing out of the outlet of the buffer pressurization chamber directly enters the gas-liquid separation chamber, and the velocity of the fluid medium in the gas-liquid separation chamber is significantly reduced due to the effect of diversion and buffer pressurization chamber, and the working fluid is fully retained in the gas-liquid separation chamber, realizing the compound pump gas-liquid separation. If there is no buffer chamber, the high-speed fluid behind the centrifugal impeller driven by the DC permanent magnet motor cannot be fully decelerated, resulting in the inability to complete the gas-liquid separation, and the impeller gas binding phenomenon will dominate, which will directly cause self-priming failure. At the same time, in order to keep the structure of the composite canned pump compact and have a good buffer effect, the secondary buffer chamber and the primary buffer chamber of the buffer booster chamber can be kept concentric, and the outlet of the secondary buffer chamber is along the circumferential, radial or secondary buffer chamber The cover plate is distributed (uniformly or non-uniformly) in a certain area. In addition, the buffer pressurization chamber and the centrifugal end can be kept concentrically distributed (as shown in Figure 30, buffer fins 11-101 in the figure, primary buffer chamber outlet 11-103, and secondary buffer chamber outlet 11-203), which can effectively improve The compactness of the overall structure.

When the self-priming compound canned pump is in the actual working stage, as shown in Figure 25 and Figure 31, the flow schematic diagram of the compound canned pump in the working stage, the fluid to be pumped in the pump inlet pipeline is sucked into the injector along the compound pump inlet, and the fluid ejected from the nozzle The high-speed working fluid enters the centrifugal end after being accelerated and mixed by the ejector throat and decelerated and pressurized by the diffusion section; then, this part of the fluid is accelerated and pressurized by the centrifugal impeller to obtain a higher speed and pressure, and then discharged from the centrifugal pressure water chamber into the The buffer pressurization chamber decelerates and pressurizes, and discharges from the outlet of the buffer pressurization chamber to realize the deceleration and pressurization of the working medium. The fluid flowing out from the outlet of the buffer pressurization chamber enters the gas-liquid separation chamber, part of the fluid is discharged through the outlet of the compound pump, and the other part of the pressurized fluid that has not been discharged from the pump body continues to circulate in the gas-liquid separation chamber to provide working fluid for the injector nozzle. The strong negative pressure formed near the outlet of the nozzle continues to entrain the fluid to be pumped at the pump inlet, and the above process is repeated in this way to realize the normal pumping of the fluid to be pumped by the composite canned pump. During this process, the buffer pressurization chamber can effectively reduce the flow resistance and reduce the pressure loss, and at the same time realize the buffer pressurization of the fluid at the outlet of the centrifugal end.

As shown in Figure 26 and Figure 28, a check valve 16 or an elastic baffle 17 can be arranged at the inlet of the injector nozzle. When the self-priming working stage starts, only the prefilled fluid circulates in the pump, and there is no fluid to be pumped. Continuous replenishment, the pressure difference on both sides of the check valve or elastic flap (inside the injector and the gas-liquid separation chamber) is small, and the check valve or elastic flap is in the open state under the action of spring force, elastic flap elastic force or electromagnetic force, The liquid inside the gas-liquid separation chamber flows into the throat of the injector through the position of the injector nozzle, where the gas-liquid mixing process is completed. With the deepening of the self-priming stage, the pressure difference between the two sides of the check valve or the elastic flap structure continues to increase due to the continuous action of the pre-filling fluid in the pump through the process of accelerating and boosting the ejector, driving the centrifugal impeller to do work, and decelerating and boosting the buffer structure. , until the end of the self-priming stage, the check valve or elastic stopper structure overcomes the spring force or electromagnetic force under the action of a large pressure difference and enters the closed state. As shown in Figure 27 and Figure 29, the check valve or the elastic flap is closed, at this time, the liquid in the gas-liquid separation chamber can no longer enter the ejector through the nozzle position, and the internal circulation of the fluid in the pump stops. In the self-priming stage, the high-speed fluid flowing in from the nozzle and the strong negative pressure caused by the diffuser section form an effective entrainment effect on the gas in the conduit, and under the action of the buffer structure, the fluid decelerates and pressurizes to complete the gas-liquid separation to realize the compound canned pump Self-priming function; during the working stage, the liquid in the gas-liquid separation chamber no longer flows back to the nozzle position, and the liquid that has done work is directly discharged through the outlet of the compound shielded pump. By using the "open" or "cut-off" of the working fluid at the nozzle inlet, the self-priming function is realized while the internal circulation in the actual working stage is stopped, thereby effectively improving the hydraulic efficiency of the pump.

To sum up, the present invention retains the characteristics of compact overall structure and high degree of integration of the canned pump. At the same time, on the premise of not increasing the operating noise of the pump, the centrifugal impeller is driven by a DC permanent magnet motor and matched with a buffer booster chamber and a gas-liquid mixing chamber (or Ejector) realizes the gas-liquid separation and self-priming of the canned pump under high-speed working conditions and improves its hydraulic characteristics.

The specific embodiment of the present invention has been described above in conjunction with the accompanying drawings, but these descriptions can not be interpreted as limiting the scope of the present invention, the protection scope of the present invention is defined by the appended claims, any claims on the basis of the present invention All modifications are within the protection scope of the present invention.

Claims

The DC permanent magnet self-priming compound canned pump is characterized in that:

Including pump inlet, gas-liquid mixing chamber, centrifugal end, buffer booster chamber, gas-liquid separation chamber and pump outlet. The inlet of the pressure chamber is connected, the outlet of the buffer pressurization chamber is connected with the gas-liquid separation chamber, and the gas-liquid separation chamber is connected with the pump outlet;

The centrifugal end specifically includes a DC permanent magnet motor, a centrifugal impeller and a centrifugal pressurized water chamber. The centrifugal impeller is located in the centrifugal pressurized water chamber and is connected to the rotor of the DC permanent magnet motor. The rotor of the DC permanent magnet motor is isolated from the stator through a shielding sleeve; The maximum speed of the DC permanent magnet motor reaches at least 3600 rpm;

The buffer pressurization chamber is used to quickly decelerate and pressurize the high-speed pressurized fluid at the outlet of the centrifugal end; in the exhaust and self-priming stage, reduce the flow rate of the gas-liquid mixed fluid while reducing bubble breakage; in the non-exhaust stage, reduce While the flow pressure loss is achieved, the buffer pressurization of the outlet fluid of the centrifugal end is realized;

The gas-liquid mixing chamber has a return hole, and communicates with the gas-liquid separation chamber through the return hole.
The DC permanent magnet self-priming compound canned pump is characterized in that:

Including pump inlet, injector, centrifugal end, buffer pressurization chamber, gas-liquid separation chamber and pump outlet, the pump inlet is connected to the injector inlet, the diffuser section of the ejector is connected to the centrifugal end inlet, and the centrifugal end outlet is connected to the buffer pressurization chamber inlet The outlet of the buffer pressurization chamber is connected with the gas-liquid separation chamber, and the gas-liquid separation chamber is connected with the pump outlet

The centrifugal end specifically includes a DC permanent magnet motor, a centrifugal impeller and a centrifugal pressurized water chamber. The centrifugal impeller is located in the centrifugal pressurized water chamber and is connected to the rotor of the DC permanent magnet motor. The rotor of the DC permanent magnet motor is isolated from the stator through a shielding sleeve; The maximum speed of the DC permanent magnet motor reaches at least 3600 rpm;

The buffer pressurization chamber is used to quickly decelerate and pressurize the high-speed pressurized fluid at the outlet of the centrifugal end; in the exhaust and self-priming stage, reduce the flow rate of the gas-liquid mixed fluid while reducing bubble breakage; in the non-exhaust stage, reduce While the flow pressure loss is achieved, the buffer pressurization of the outlet fluid of the centrifugal end is realized;

The injector communicates with the gas-liquid separation chamber through a nozzle.
According to claim 1 or 2, the DC permanent magnet self-priming compound canned pump is characterized in that: the outlet of the buffer pressurization chamber is distributed along the circumferential or radial direction in the plane, or the pores are arranged in space.
According to claim 1 or 2, the DC permanent magnet self-priming composite canned pump is characterized in that: the buffer pressurization chamber is a series structure of porous laminates, a porous space structure, a porous medium filling structure, a single The structure of the combination of circuitous channels or the structure of a combination of multiple circuitous channels.
The DC permanent magnet self-priming compound canned pump according to claim 4, characterized in that: fixed or rotating guide vanes are added in the buffer booster cavity of the series structure of porous laminates, or the buffer booster The inlet and outlet of the cavity are set as rotatable guide vanes.
According to claim 1 or 2, the DC permanent magnet self-priming compound shielded pump is characterized in that: the buffer pressurization chamber and the centrifugal impeller are distributed up and down or concentrically; when distributed up and down, the outlet of the centrifugal end communicates through the diversion chamber Buffer plenum chamber.
The DC permanent magnet self-priming compound shielded pump according to claim 1, characterized in that: a check valve is arranged at the return hole of the gas-liquid mixing chamber, and when the self-priming stage of the compound shielded pump ends, the check valve Driven by the pressure difference inside and outside the gas-liquid mixing chamber, the liquid in the gas-liquid separation chamber can no longer enter the gas-liquid mixing chamber through the position of the return hole, and the circulating flow in the pump is cut off.
The self-priming compound canned pump according to claim 2, characterized in that: a check valve is arranged at the inlet of the injector nozzle, and when the self-priming stage of the compound canned pump is completed, the check valve is within the pressure difference between the inside and outside of the injector. Closed by driving, the liquid in the gas-liquid separation chamber can no longer enter the injector through the nozzle position, and the circulation flow in the pump is cut off.
The DC permanent magnet self-priming compound canned pump according to claim 1 or 2, characterized in that: there is at least one buffer pressurization chamber, at least one centrifugal end, and at least one centrifugal end outlet.
A combined self-priming compound canned pump, comprising at least one self-priming compound canned pump according to any one of claims 1 to 9 and at least one centrifugal pump, characterized in that: the self-priming compound canned pump It is connected in parallel with the inlet of the centrifugal pump, and the outlet of the self-priming composite canned pump is connected in parallel with the centrifugal pump.