High-efficiency variable frequency submersible axial flow pump

Abstract

The utility model discloses a kind of high-efficiency variable frequency submersible axial flow pumps, including three-phase permanent magnet synchronous submersible motor, the three-phase permanent magnet synchronous submersible motor setting stator, rotor, the stator includes stator embedded wire, the rotor includes rotor core, motor shaft and embedded permanent magnet, the frequency converter of the motor is set in frequency control cover inside, the shaft extension of the motor shaft is connected with impeller;The water inlet end of the upper end cover of the three-phase permanent magnet synchronous submersible motor is connected with the water inlet section, namely motor uses lower design, the water outlet end of the water inlet section is connected with the water inlet end of guide piece, the water outlet end of the guide piece is connected with the water inlet end of water outlet connector, namely water flow direction is from bottom to top.The utility model three-phase permanent magnet synchronous submersible motor uses variable frequency starting, and starting current is small;Motor uses lower design, and impeller and motor are coaxial, so that overall structure gravity center is reduced, and stability is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of submersible axial flow pumps, specifically to a high-efficiency variable frequency submersible axial flow pump. Background Technology

[0002] Submersible axial flow pumps, as a type of high-flow, low-head water pump, are widely used in agricultural irrigation, flood control and drainage, and fishpond water supply and drainage. Existing structures mainly use AC asynchronous motors for drive, directly starting and running via industrial frequency power, and the main components are made of cast metal. This design has the following defects and shortcomings:

[0003] 1. Low energy efficiency: The efficiency of traditional asynchronous motors drops significantly under non-rated operating conditions. Especially in agricultural irrigation and drainage, the flow rate needs to be frequently adjusted, and the motor is often in a low-load state, resulting in serious energy waste.

[0004] 2. Heavy weight and large size: Existing submersible axial flow pumps are all made of castings. The high specific gravity of metal makes the entire pump too heavy. Since they are used in fields and rural areas, they have to be carried by hand during transportation, which brings many inconveniences to their use.

[0005] 3. The starting current is large. When starting directly at the power frequency, the starting current of the asynchronous motor can reach 5-7 times the rated current. This can impact the relatively weak power grid in rural areas, easily causing voltage fluctuations and affecting other electrical equipment.

[0006] 4. Poor corrosion resistance: With the rise of coastal aquaculture, seawater transportation has become commonplace. Cast iron is not resistant to seawater corrosion, often causing water pumps to fail prematurely.

[0007] 5. Traditional asynchronous motors have poor adaptability, operate at a fixed speed, and lack automatic protection functions such as overvoltage, overcurrent, overload, and overheating. Utility Model Content

[0008] This invention provides a high-efficiency variable frequency submersible axial flow pump to overcome the aforementioned problems in the prior art.

[0009] The technical solution of this application is as follows:

[0010] A high-efficiency variable frequency submersible axial flow pump includes a three-phase permanent magnet synchronous submersible motor. The three-phase permanent magnet synchronous submersible motor includes a base, a variable frequency control cover at the bottom of the base, a variable frequency controller installed inside the variable frequency control cover, a stamping machine base on the upper part of the base, and an upper end cover on the upper part of the stamping machine base. The base, stamping machine base, and upper end cover together form a motor cavity. A stator and a rotor are arranged inside the motor cavity. The stator includes stator windings, and the rotor includes a rotor core, a motor shaft, and embedded permanent magnets. The shaft extension of the motor shaft is connected to an impeller. A first support bearing and a second support bearing are arranged at both ends of the motor shaft. The first support bearing is arranged in a bearing hole in the base, and the second support bearing is arranged in a bearing hole in the upper end cover. The upper end cover of the three-phase permanent magnet synchronous submersible motor is connected to the inlet end of a water inlet section. The outlet end of the water inlet section is connected to the inlet end of a guide member, and the outlet end of the guide member is connected to the inlet end of an outlet connector.

[0011] Compared to traditional AC asynchronous motors, this invention employs a three-phase permanent magnet synchronous submersible motor with a permanent magnet rotor, featuring high efficiency, high power factor, wide operating range, and high-efficiency zone. Its efficiency is 5% higher than that of traditional motors. It utilizes frequency conversion starting, resulting in a low starting current. Furthermore, the upper cover of the three-phase permanent magnet synchronous submersible motor is connected to the water inlet end of the inlet section, employing a bottom-mounted design. The impeller and the three-phase permanent magnet synchronous submersible motor are coaxial, lowering the overall structural center of gravity and enhancing stability. In addition, the frequency converter is located inside the frequency converter control cover, ensuring good sealing and high reliability. Compared to conventional frequency converter motors with external control boxes, this invention boasts a compact structure and superior overall product integrity.

[0012] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, the variable frequency control cover and the base together form a wiring cavity, and a die-cast cable sealing device is installed on the outside of the wiring cavity. The cable sealing device prevents water from entering the wiring cavity.

[0013] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, the wiring cavity is provided with a first leak test hole, and the motor cavity is provided with a second leak test hole. The first and second leak test holes are used for leak testing after the motor is assembled. The second leak test hole also serves to lubricate the motor cavity, allowing for subsequent oil filling and enhancing the motor's heat dissipation.

[0014] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, the base is equipped with a lead wire sealing device. This lead wire sealing device is used to prevent oil from entering the wiring cavity from the motor cavity after the motor is filled with oil.

[0015] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, the upper and lower ends of the press base are respectively provided with flanged flanges, which are connected to the base and the upper end cover respectively. The flanged flange structure is used to fix the press base to the base and the upper end cover.

[0016] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, an oil isolation chamber is provided between the three-phase permanent magnet synchronous submersible motor and the inlet section. The oil isolation chamber is composed of a sealing cover and an upper end cover connected together. A second mechanical seal is provided on the outside of the oil isolation chamber, and a first mechanical seal is provided on the inside of the oil isolation chamber. A water ejector is provided on the outside of the second mechanical seal. The second mechanical seal is used to prevent water from entering the oil isolation chamber, and the first mechanical seal is used to prevent oil from entering the motor cavity. The water ejector is used to prevent the second mechanical seal from being entangled by aquatic plants or floating objects.

[0017] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, a rubber bearing is installed inside the guide member, and the rubber bearing is connected to the shaft extension end of the motor shaft. The rubber bearing changes the impeller from cantilever support to two-end support, improving impeller stability and reducing motor shaft deflection.

[0018] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, the outer side of the water outlet connector is connected to a delivery hose, and the inner side of the water outlet connector is connected to a drain pipe. An adhesive socket is provided on the inner side of the water outlet connector for adhesive bonding to the drain pipe, which is used to deliver water and is made of polyvinyl chloride (PVC).

[0019] Preferably, in the aforementioned high-efficiency variable frequency submersible axial flow pump, O-rings are provided on the mounting stops of the upper end cover, base, and variable frequency control cover. Due to the bottom-mounted design of the three-phase permanent magnet synchronous submersible motor, sealing is particularly important. This invention uses O-rings, along with cable sealing devices, mechanical seals, sealing covers, and lead-out wire sealing devices, to improve the sealing performance of the submersible axial flow pump.

[0020] The beneficial technical effects of this utility model are as follows: (1) Lightweight, low center of gravity, and high stability: The overall layout adopts a three-phase permanent magnet synchronous submersible motor with a bottom-mounted design. Under the same flow rate, head, and power, the weight of the pump is one-quarter of that of a traditional submersible axial flow pump. The three-phase permanent magnet synchronous submersible motor is located below the inlet section, and the impeller and the three-phase permanent magnet synchronous submersible motor are coaxial, which lowers the center of gravity of the overall structure and enhances stability. (2) High energy efficiency: The power part of this utility model adopts a three-phase permanent magnet synchronous submersible motor. Its rotor is a permanent magnet, which has the characteristics of high efficiency, high power factor, wide range, and high efficiency zone. Its efficiency is 5% higher than that of traditional motors. (3) Low starting current: The three-phase permanent magnet synchronous submersible motor adopts frequency conversion starting, which results in a low starting current. (4) Corrosion resistance: Some structures are made of non-metallic materials, such as reinforced nylon for the guide parts and stainless steel for the impeller, which can enhance the corrosion resistance and wear resistance of the pump structure and extend the pump's life. (5) Automatic motor protection function: Through the design of the permanent magnet motor, the pump can achieve soft start and operate within a wide voltage range; the motor windings are connected to the built-in frequency converter. When the frequency converter receives signals such as overvoltage, overcurrent, overload, or overheating, it will automatically reduce the operating frequency and speed to keep the operating current within the allowable range, thereby protecting the motor. In addition, the frequency converter is located inside the frequency converter control cover, which has a good sealing effect and high reliability. Compared with the conventional external control box type of frequency converter motor, this utility model has a compact structure and good overall product integrity. Attached Figure Description

[0021] Figure 1 This is a structural schematic diagram of the high-efficiency variable frequency submersible axial flow pump of this utility model.

[0022] Figure 2 This is a utility model Figure 1 A cross-sectional view of a high-efficiency variable frequency submersible axial flow pump.

[0023] Figure 3 This is a partial cross-sectional view of the base of the high-efficiency variable frequency submersible axial flow pump of this utility model.

[0024] Figure 4 This is a partial cross-sectional view of the base of the high-efficiency variable frequency submersible axial flow pump of this utility model.

[0025] Figure 5 This is a schematic diagram of the inlet section of the high-efficiency variable frequency submersible axial flow pump of this utility model.

[0026] Figure 6 This is a schematic diagram of the impeller structure of the high-efficiency variable frequency submersible axial flow pump of this utility model.

[0027] Figure 7 This is a schematic diagram of the guide component structure of the high-efficiency variable frequency submersible axial flow pump of this utility model.

[0028] The labels in the attached diagram are as follows: 1-Variable frequency control cover; 2-Base; 3-Cable sealing device; 4-Support bearing; 41-First support bearing; 42-Second support bearing; 5-Pressing machine base; 6-Rotor core; 7-Motor shaft; 8-Stator winding; 9-Upper end cover; 10-Mechanical seal; 101-First mechanical seal; 102-Second mechanical seal; 11-Sealing cover; 12-Water separator; 13-Water inlet section; 14-Impeller; 15-Guide component; 16-Rubber bearing; 17-Water outlet connector; 18-Drain pipe; 19-First leak test hole; 20-Second leak test hole; 21-Lead wire sealing device; 22-Embedded permanent magnet; 23-Shaft extension. Detailed Implementation

[0029] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings, but this should not be construed as limiting the present utility model. Contents not described in detail in the following embodiments are all common knowledge in the art or can be implemented using conventional technical means in the art.

[0030] Reference to embodiments of this utility model Figure 1-7 .

[0031] like Figure 1 and 2 As shown, the high-efficiency variable frequency submersible axial flow pump of this utility model includes a three-phase permanent magnet synchronous submersible motor, an inlet section 13, an impeller 14, a guide 15, an outlet connector 17, and a drain pipe 18 arranged sequentially from bottom to top.

[0032] like Figure 2 As shown, the three-phase permanent magnet synchronous submersible motor includes a base 2, which is integrally injection molded from nylon PA66 reinforced with 30% glass fiber. A frequency converter control cover 1 is connected to the bottom of the base 2, and a stamping machine base 5 is connected to the upper part of the base 2. An upper end cover 9 is connected to the upper part of the stamping machine base 5. The base 2, the stamping machine base 5, and the upper end cover 9 together constitute the motor cavity of the three-phase permanent magnet synchronous submersible motor. Figure 2 As shown, a frequency converter controller is installed on the inside of the frequency converter control cover 1, and is filled with heat dissipation potting compound.

[0033] like Figure 2 As shown, the frequency converter control cover 1 and the base 2 together form a wiring cavity. A cable sealing device 3 is provided on the outside of the wiring cavity to prevent water from entering the wiring cavity.

[0034] like Figure 4 As shown, the base 2 is provided with a second leak test hole 20 for the motor cavity and a first leak test hole 19 for the wiring cavity, for leak testing after the motor is assembled. The second leak test hole 20 also serves to add oil, so that the motor cavity can be filled with oil later, and it can also enhance the heat dissipation of the motor.

[0035] like Figure 3 As shown, the base 2 is provided with a lead wire sealing device 21, which is used to prevent oil from entering the wiring cavity from the motor cavity after the motor is filled with oil.

[0036] like Figure 2 As shown, the stator of the three-phase permanent magnet synchronous submersible motor consists of a stamping base 5 and stator windings 8. The upper and lower ends of the stamping base 5 are respectively provided with flanged flanges, which are connected to the base 2 and the upper end cover 9 to fix the stamping base 5. The rotor of the three-phase permanent magnet submersible motor is supported in the bearing holes of the upper end cover 9 and the base 2. The rotor of the three-phase permanent magnet synchronous submersible motor consists of a rotor core 6, embedded permanent magnets 22, a motor shaft 7, and support bearings 4 at both ends of the motor shaft 7. The support bearings 4 include a first support bearing 41 and a second support bearing 42. The first support bearing 41 is disposed in the bearing hole of the base 2, and the second support bearing 42 is disposed in the bearing hole of the upper end cover 9.

[0037] like Figure 2 As shown, the upper end of the motor shaft 7 of the three-phase permanent magnet submersible motor is a shaft extension 23, which is connected to the impeller 14. The impeller 14 is cast from stainless steel 304.

[0038] like Figure 2 As shown, an oil isolation chamber is provided between the three-phase permanent magnet synchronous submersible motor and the water inlet section 13. The oil isolation chamber is composed of a sealing cover 11 and an upper cover 9 connected together, and is filled with oil. The sealing cover 11 is made of stretched stainless steel plate. A second mechanical seal 102 is provided on the outside of the oil isolation chamber, and a first mechanical seal 101 is provided on the inside of the oil isolation chamber. The second mechanical seal 102 is used to prevent water from entering the oil isolation chamber, and the first mechanical seal 101 is used to prevent oil from entering the motor cavity. A water ejector 12 is provided on the outside of the second mechanical seal 102 to prevent the second mechanical seal 102 from being entangled by aquatic plants or floating objects.

[0039] like Figure 2 , Figure 5 , Figure 6 As shown, the lower end of the inlet section 13 is bolted to the upper end cover 9 and the stamping machine base 5 of the three-phase permanent magnet synchronous submersible motor, and the upper end of the inlet section 13 is bolted to the guide member 15. The inlet section 13 is the water inlet of the submersible axial flow pump of this utility model. The inlet section 13 is integrally injection molded from nylon PA66 reinforced with 30% glass fiber. The inlet section 13 and the guide member 15 form the pressure working chamber of the submersible axial flow pump. The guide member 15 is integrally injection molded from nylon PA66 reinforced with 30% glass fiber. The guide member 15 has a support inside, and a rubber bearing 16 is installed in the support, so that the impeller 14 is changed from cantilever support to two-end support, thereby reducing the deflection of the motor shaft 7.

[0040] like Figure 2 , Figure 7 As shown, the upper end of the guide member 15 is bolted to the water outlet connector 17. The outer diameter of the water outlet connector 17 is the connection point between the submersible axial flow pump and the delivery hose. The inner diameter of the water outlet connector 17 is also provided with an adhesive socket for adhesive bonding of the drain pipe 18. The drain pipe 18 is used to transport water and is made of polyvinyl chloride (PVC). The drain pipe 18 is relatively long. Figure 2 Only a portion of it is shown.

[0041] In this utility model, the mounting stops on the upper end cover 9, the base 2, and the frequency conversion control cover 1 are all provided with grooves for installing O-ring seals, which are used to install O-ring seals and prevent water from entering the motor cavity and wiring cavity from the mounting stops.

[0042] The working process of this utility model is as follows: The three-phase permanent magnet synchronous submersible motor is started, driving the impeller 14 to rotate. Water is continuously drawn in through the inlet of the inlet section 13. The lift generated by the rotation of the impeller 14 pushes the water from the blade inlet to the blade outlet. Then, the guide member 15 converts the rotational motion of the water flow into axial motion, achieving axial transport, and finally discharging it through the outlet connector 17. Figure 2 In the image, the arrow indicates the direction of water flow.

[0043] The foregoing general description of the utility model and its specific embodiments should not be construed as limiting the technical solution of the utility model. Those skilled in the art, based on the disclosure of this application, can add, reduce, or combine the disclosed technical features in the foregoing general description and / or specific embodiments (including examples) without departing from the constituent elements of the utility model, to form other technical solutions within the protection scope of this utility model.

Claims

1. A high-efficiency variable frequency submersible axial flow pump, characterized in that: The invention includes a three-phase permanent magnet synchronous submersible motor. The three-phase permanent magnet synchronous submersible motor includes a base (2), a frequency converter control cover (1) is provided at the bottom of the base (2), a frequency converter controller is installed inside the frequency converter control cover (1), a stamping machine base (5) is provided on the upper part of the base (2), and an upper end cover (9) is provided on the upper part of the stamping machine base (5). The base (2), the stamping machine base (5) and the upper end cover (9) together form a motor cavity. A stator and a rotor are provided in the motor cavity. The stator includes stator windings (8), and the rotor includes a rotor core (6), a motor shaft (7) and embedded permanent magnets (22). The motor shaft (7) has a shaft extension (23) connected to the impeller (14); the motor shaft (7) has a first support bearing (41) and a second support bearing (42) at both ends. The first support bearing (41) is located in the bearing hole of the base (2), and the second support bearing (42) is located in the bearing hole of the upper end cover (9); the upper end cover (9) of the three-phase permanent magnet synchronous submersible motor is connected to the water inlet end of the water inlet section (13), the water outlet end of the water inlet section (13) is connected to the water inlet end of the guide (15), and the water outlet end of the guide (15) is connected to the water inlet end of the water outlet connector (17).

2. The high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: The frequency converter control cover (1) and the base (2) together form a wiring cavity, and the outer side of the wiring cavity is a die-cast cable sealing device (3).

3. The high-efficiency variable frequency submersible axial flow pump according to claim 2, characterized in that: The wiring cavity is provided with a first leak test hole (19), and the motor cavity is provided with a second leak test hole (20).

4. The high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: The base (2) is provided with a lead wire sealing device (21).

5. The high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: The upper and lower ends of the press base (5) are respectively provided with flanges, which are connected to the base (2) and the upper end cover (9).

6. The high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: An oil isolation chamber is provided between the three-phase permanent magnet synchronous submersible motor and the water inlet section (13). The oil isolation chamber is composed of a sealing cover (11) and an upper end cover (9). A second mechanical seal (102) is provided on the outside of the oil isolation chamber, a first mechanical seal (101) is provided on the inside of the oil isolation chamber, and a water-spinning device (12) is provided on the outside of the second mechanical seal (102).

7. The high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: The guide member (15) is equipped with a rubber bearing (16), which is connected to the end of the shaft extension (23) of the motor shaft (7).

8. The high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: The water outlet connector (17) is connected to a delivery hose on the outside and to a drain pipe (18) on the inside.

9. A high-efficiency variable frequency submersible axial flow pump according to claim 1, characterized in that: The mounting stops on the upper cover (9), base (2), and frequency converter control cover (1) are all equipped with O-ring seals.

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