Shaftless impeller self-cooling shield pump

Abstract

The invention relates to the technical field of shield pump cooling, in particular to a shaftless impeller self-cooling shield pump. The rotation gap between the rotor and the stator is designed, and the liquid working medium is driven by the pressure difference to circularly flow back in the rotation gap, so that natural cooling of the interior of the shield pump is realized. Due to the design of the rotary gap, heat generated in the working process of the shield pump is effectively dissipated, the working temperature of the shield pump is reduced, equipment damage caused by overheating is avoided, the operation stability of the shield pump is improved, and the service life of the shield pump is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of shielded pump cooling, and in particular to a shaftless impeller self-cooling shielded pump. Background Art

[0002] Most of the pumps currently used in production are connected to the impeller through the motor shaft. The motor drives the shaft to rotate, and the shaft drives the impeller to rotate accordingly, thereby achieving the effect of pressurizing the fluid. During the long-term use of this type of pump, the motor shaft is easily damaged by vibration, affecting the performance of the pump. The shaftless pump push technology that came into being effectively solves this defect. The shaftless pump integrates the shaftless impeller and the rotor. Compared with the shaft-type pump push technology, it has smaller leakage, longer service life, wider application prospects and development value.

[0003] In recent years, shaftless pump propulsion technology has been continuously developed. For example, the existing technologies CN113503260A, CN111927790A, CN115324904A and CN109026739A all adopt the design of shaftless impellers, and the patent application CN116641899A combines the advantages of shaftless pumps and shielded pumps to solve the problem of fluid leakage between the stator and the rotor. However, in the design process of the above-mentioned existing technologies, conventional heat sinks are used to dissipate heat from the pump, but the heat dissipation efficiency of this method is low, and it is difficult to meet the requirements of rapid heat dissipation and cooling of the heat generated by the internal rotor and stator of the shielded pump during operation, which makes the shielded pump have a greater risk of burning due to excessive internal temperature, so it is urgent to solve it. Summary of the invention

[0004] In order to avoid and overcome the technical problems existing in the prior art, the present application provides a shaftless impeller self-cooling canned pump. The present application can effectively dissipate the heat inside the canned pump, thereby reducing the operating temperature of the canned pump and further preventing the canned pump from burning due to overheating.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] A shaftless impeller self-cooling shielded pump comprises a pump casing, and a rotor, a stator and a shaftless impeller which are installed in the pump casing and cooperate with each other, a rotating gap is formed between the rotor and the stator, an inlet of the rotating gap is connected with an outlet of a flow channel of the shaftless impeller, an outlet of the rotating gap is connected with an inlet of the flow channel, and a pressure at the outlet of the rotating gap is lower than a pressure at the inlet of the rotating gap, so that a liquid working medium is driven to circulate and reflux in the rotating gap by a pressure difference.

[0007] As a further solution of the present application: the stator is coaxially fixedly mounted on the inner wall of the pump casing; a bearing seat is fixedly mounted at both ends of the inside of the pump casing, and both ends of the sleeve in the shaftless impeller are respectively mounted on corresponding bearing seats through bearings; the stator and the rotor coaxially fixedly connected to the outer wall of the sleeve do not contact each other, and an installation gap is formed between the two; a return channel connecting the matching gap and the flow channel is opened on the two bearing seats, and the two return channels and the installation gap are connected and matched in sequence to form the said rotation gap.

[0008] As a further solution of the present application: thrust plates are fixedly connected to both ends of the sleeve, the two thrust plates are located between the two bearings, and a first gap is formed between the two thrust plates and the inner end faces of the bearing seats adjacent to them, and the two first gaps are directly connected to the return channels adjacent to them respectively; the rotor is located between the two thrust plates, and the rotor fits against one of the thrust plates, and an annular groove coaxially arranged with the sleeve is formed between the rotor and the other thrust plate; the stator is coaxially embedded in the annular groove, and a fourth gap is formed between the stator and the annular groove; a second gap is formed between the outer circumferential surfaces of the two thrust plates and the inner wall of the pump casing, and a third gap is formed between the outer circumferential surface of the rotor and the inner wall of the pump casing, and the two first gaps, the two second gaps, the third gap and the fourth gap are connected and matched in sequence to form the installation gap.

[0009] As a further solution of the present application: the bearing used is a thrust bearing.

[0010] As a further solution of the present application: the thrust plate and its adjacent thrust bearing cooperate to form a friction pair.

[0011] As a further solution of the present application: both ends of the pump housing are covered with end covers, and both end covers are provided with flow holes coaxially arranged with the sleeve, and both flow holes are connected to the flow channel.

[0012] As a further solution of the present application: a lead hole is provided on the pump casing, and a lead wire on the stator for connecting to an external power source passes through the lead hole and out of the pump casing.

[0013] As a further solution of the present application: blades are installed in the flow passage of the sleeve.

[0014] As a further solution of the present application: a spiral groove is provided on the end surface of the rotor facing the stator.

[0015] As a further solution of the present application: a diamond-like coating is provided at the position where the outer side of the sleeve cooperates with the bearing.

[0016] Compared with the prior art, the beneficial effects of this application are:

[0017] 1. This application realizes natural cooling inside the canned pump by designing the rotary gap between the rotor and the stator and using the pressure difference to drive the liquid working medium to circulate and reflux in the rotary gap. The design of the rotary gap not only effectively dissipates the heat generated during the operation of the canned pump and reduces the operating temperature of the canned pump, but also avoids equipment damage caused by overheating and improves the operating stability and service life of the canned pump.

[0018] 2. By fixing the bearing seat inside the pump housing and installing the sleeve of the shaftless impeller on the bearing seat through the bearing, the installation gap between the rotor and the stator is more stable, and a complete path of the rotary gap is formed. The design of the bearing seat not only ensures the stability of the shielded pump structure, but also optimizes the circulation and reflux channel of the liquid working medium and improves the cooling efficiency.

[0019] 3. The design of the thrust plate and the first gap, the second gap, the third gap and the fourth gap not only increases the path for the circulation of the liquid working medium, but also further enhances the cooling effect through the connection and coordination of multiple gaps. In addition, it also improves the installation accuracy between the rotor and the stator, ensuring the stable operation of the shielded pump.

[0020] 4. The use of thrust bearings effectively supports and positions the shaftless impeller in the axial direction, improving the running stability and reliability of the shielded pump. At the same time, the thrust bearings can also withstand large axial loads, extending the service life of the shielded pump.

[0021] 5. A friction pair is formed between the thrust plate and its adjacent thrust bearing, which not only reduces friction loss, but also improves the sealing performance of the shielded pump, prevents liquid working fluid leakage and impurities from entering the pump, and ensures the normal operation of the shielded pump.

[0022] 6. The design of the end cover and the flow hole provides the necessary channel for the circulation and reflux of the liquid working medium, while ensuring the integrity of the shielded pump structure, which not only improves the cooling efficiency, but also makes the installation and maintenance of the shielded pump more convenient.

[0023] 7. The design of the lead hole allows the lead wire on the stator used to connect the power supply to pass through the pump casing smoothly, ensuring the normal power supply of the shielded pump. At the same time, the lead hole also has a certain sealing performance, preventing the liquid working medium from entering the pump and causing short circuit and other faults.

[0024] 8. Installing a shaftless impeller in the flow channel of the sleeve not only simplifies the structure of the shielded pump, but also improves the liquid working fluid performance of the pump. The design of the shaftless impeller makes the liquid working fluid flow more smoothly, reduces energy loss, and improves the efficiency of the pump.

[0025] 9. The spiral grooves on the end surface of the rotor facing the stator can guide the liquid working medium to form a more complex flow path between the rotor and the stator, increasing the contact area between the liquid working medium and the rotor and the stator, thereby improving the cooling effect.

[0026] 10. A diamond-like coating is provided at the position where the outer side of the sleeve matches the bearing, which not only improves the hardness and wear resistance of the sleeve, but also extends the service life of the bearing, so that the shielded pump can maintain stable operating performance even under harsh working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the rotary clearance in this application.

[0028] Figure 2 This is a schematic diagram of the overall structure of this application.

[0029] Figure 3 This is a schematic diagram of the structure after adding a rotor in this application.

[0030] In the figure: 1, pump body assembly; 10, pump housing; 101, lead wire port; 11, end cover; 11a, front bearing end cover; 11a1, pump inlet; 11b, rear bearing end cover; 11b1, pump outlet; 12, bearing seat; 12a, front bearing seat; 12b, rear bearing seat; 121, return channel; 2, shielded motor; 20, stator; 201, lead wire; 21, rotor; 211, third gap; 21 2. Spiral groove; 22. Stator shielding sleeve; 221. First shielding plate; 222. Second shielding plate; 223. Shielding ring; 23. Bearing; 23a. Front bearing; 22b. Rear bearing; 24. Fourth gap; 3. Shaftless impeller; 31. Sleeve; 32. Blade; 33. Thrust plate; 33a. Front thrust plate; 33b. Rear thrust plate; 34. First gap; 25. Second gap; 4. Rotational gap. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] See also Figure 1 to Figure 3 In an embodiment of the present application, a shaftless impeller canned pump with anti-corrosion stator includes a pump body assembly 1, a canned motor 2 and a shaftless impeller 3.

[0033] The pump body assembly 1 includes a cylindrical pump housing 10, in which an end cover 11 and a bearing seat 12 are installed. The end cover 11 is divided into a front bearing end cover 11a and a rear bearing end cover 11b, and the bearing seat 12 is divided into a front bearing seat 12a and a rear bearing seat 12b. The front bearing end cover 11a and the front bearing seat 12a are both installed at the inlet of the pump housing 10, and the front bearing seat 12a is located on the inner side of the front bearing end cover 11a, and the two are arranged in close contact with each other. Similarly, the rear bearing end cover 11b and the rear bearing seat 12b are installed at the outlet of the pump housing 10 in the same way. There are flow holes at the axis of the front bearing end cover 11a, the front bearing seat 12a, the rear bearing end cover 11b and the rear bearing seat 12b, and each flow hole is coaxially arranged and connected at both ends of the sleeve 31 respectively.

[0034] The shielded motor 2 includes an annular stator 20, which is coaxially fixedly mounted on the inner wall surface of the pump housing 10. In order to facilitate power supply, a lead-in port 101 is provided on the pump housing 10, and the lead-in port 201 on the stator 20 passes through the lead-in port 101 and is connected to an external power supply to provide power to the shielded motor 2. In order to improve the sealing performance of the stator 20 during operation, a stator shielding sleeve 22 is provided on the outer sealing sleeve of the stator 20. The stator shielding sleeve 22 includes a shielding ring 223 coaxially sleeved in the axial center hole of the stator 20, and a first shielding plate 221 and a second shielding plate 222 coaxially distributed on both sides of the stator 20, and the first shielding plate 221, the shielding ring 223 and the second shielding ring 223 are sequentially connected and cooperate to form an annular receiving groove covered on the outer side of the stator 20, and the notch of the receiving groove is sealed and fitted with the inner wall of the pump housing 10 to cooperate with the pump housing 10 to form a sealed cavity covering the stator 20.

[0035] The shielded motor 2 also includes a hollow disc-shaped rotor 21, which is coaxially fixed to the outer wall of the sleeve 31 of the shaftless impeller 3. Both ends of the sleeve 31 are rotatably connected to the corresponding bearing seat 12 through bearings 23. The front end of the sleeve 31 is rotatably connected to the front bearing seat 12a through the front bearing 23a, and the rear end of the sleeve 31 is rotatably connected to the rear bearing seat 12b through the rear bearing 23b. At this point, the sleeve 31 is coaxially rotatably installed inside the pump housing 10. Two thrust plates 33 are also coaxially fixedly installed at both ends of the sleeve 31, and the two thrust plates 33 are both located on the inner side of the corresponding bearing 23, and cooperate with the bearing 23 to form a friction pair. The bearing 23 used in this embodiment is a thrust bearing.

[0036] The rotor 21 and one of the thrust bearings are arranged in close contact with each other and cooperate with the other thrust plate 33 to form an annular groove. The stator 20 is coaxially embedded in the annular groove, and a fourth gap 24 with a U-shaped cross-section is formed between the shielding sleeve on the outside of the stator 20 and the annular groove.

[0037] A first gap 34 is formed between the two thrust plates 33 and the inner end surface of the bearing seat 12 adjacent thereto, and a return channel 121 is provided on the front bearing seat 12a and the rear bearing seat 12b. One port of the return channel is provided on the inner side surface of the bearing seat 12, and the other port is provided on the hole wall of the axial center hole of the bearing seat 12, so as to be directly connected with the flow channel in the sleeve 31. A second gap 25 is formed between the outer circumferential surface of the two thrust plates 33 and the inner wall of the pump housing 10, and a third gap 211 is formed between the outer circumferential surface of the rotor 21 and the inner wall of the pump housing 10. The two first gaps 34, the two second gaps 25, the third gap 211 and the fourth gap 24 are connected and matched in sequence to form the installation gap. The two return channels 121 and the installation gap are connected and matched in sequence to form the rotation gap 4.

[0038] During the use of the present application after assembly, the liquid enters the flow channel from the pump inlet 11a1 and flows out from the pump outlet 11b1 along the flow channel. During the flow of the liquid, since the pressure at the pump inlet is lower than the pressure at the pump outlet 11b1, a portion of the liquid will flow along the reflux channel 121 on the rear bearing seat 12b to the first gap 34 at the rear end, and then flow through the second gap 25 at the rear end, the fourth gap 24, the third gap 211, the second gap 25 at the front end, the first gap 34 at the front end, and finally flow back to the flow channel from the reflux channel 121 in the front bearing seat 12a. This reciprocating process can effectively take away the heat inside the shielded motor 2 through the liquid working medium, thereby reducing the temperature inside the shielded motor 2 and avoiding overheating and burning.

[0039] like Figure 3 As shown, in order to further improve the efficiency of the canned motor 2, a rotor 21 is also installed on the other side of the stator 20, and the two rotors 21 are arranged symmetrically. At this time, a corresponding annular groove is formed between the two rotors 21, and a fourth gap 24 is generated. At the same time, a spiral groove 212 is opened on the inner side surface of the rotor 21 near the pump outlet 11b1. When the shaftless impeller 330 rotates, the liquid working medium will be sucked into the spiral groove 212213, thereby forming a high-pressure area here, which plays a role in balancing the axial force. A third gap 211 will also be formed between the newly added rotor 21 and the pump housing 10, and the liquid working medium will also flow through the third gap 211 during the flow process.

[0040] The above is only a preferred specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes within the technical scope disclosed in the present application according to the technical solution and inventive concept of the present application, which should be covered by the protection scope of the present application.

Claims

1. A shaftless impeller self-cooling canned pump, comprising a pump housing (10), and a rotor (21), a stator (20) and a shaftless impeller (3) installed in the pump housing (10) and matching with each other, characterized in that: A rotating gap (4) is formed between the rotor (21) and the stator (20), the inlet of the rotating gap (4) and the outlet of the flow channel of the shaftless impeller (3) are connected to each other, the outlet of the rotating gap (4) and the inlet of the flow channel are connected to each other, and the pressure at the outlet of the rotating gap (4) is lower than the pressure at the inlet of the rotating gap (4), so that the liquid working medium is driven to circulate and reflux in the rotating gap (4) through the pressure difference.

2. A shaftless impeller self-cooling canned motor pump according to claim 1, characterized in that: The stator (20) is coaxially fixedly mounted on the inner wall of the pump housing (10); a bearing seat (12) is fixedly mounted at both ends of the pump housing (10); and both ends of the sleeve (31) in the shaftless impeller (3) are respectively mounted on the corresponding bearing seats (12) through bearings (23); the stator (20) and the rotor (21) coaxially fixedly mounted on the outer wall of the sleeve (31) do not contact each other, and a mounting gap is formed between the two; both bearing seats (12) are provided with a return channel (121) connecting the matching gap and the flow passage, and the two return channels (121) and the mounting gap are connected and matched in sequence to form the rotation gap (4).

3. A shaftless impeller self-cooling canned motor pump according to claim 2, characterized in that: Both ends of the sleeve (31) are fixedly connected with thrust plates (33), the two thrust plates (33) are located between the two bearings (23), and a first gap (34) is formed between the two thrust plates (33) and the inner end surface of the bearing seat (12) adjacent thereto, and the two first gaps (34) are directly connected to the return flow channels (121) adjacent thereto respectively; the rotor (21) is located between the two thrust plates (33), and the rotor (21) and one of the thrust plates (33) are in contact with each other, and a gap with the sleeve (12) is formed between the rotor (21) and the other thrust plate (33). The stator (20) is coaxially embedded in the annular groove, and a fourth gap (24) is formed between the stator (20) and the annular groove; a second gap (25) is formed between the outer circumferential surfaces of the two thrust plates (33) and the inner wall of the pump housing (10); a third gap (211) is formed between the outer circumferential surface of the rotor (21) and the inner wall of the pump housing (10); the two first gaps (34), the two second gaps (25), the third gap (211) and the fourth gap (24) are connected and matched in sequence to form the installation gap.

4. A shaftless impeller self-cooling canned motor pump according to claim 3, characterized in that: What bearing (23) adopts is thrust bearing.

5. The shaftless impeller self-cooling canned motor pump according to claim 4, characterized in that: The thrust plate (33) cooperates with the adjacent thrust bearing to form a friction pair.

6. A shaftless impeller self-cooling canned motor pump according to claims 1-5, characterized in that: Both ends of the pump housing (10) are covered with end covers (11), and both end covers (11) are provided with flow holes coaxially arranged with the sleeve (31), and both flow holes are communicated with the flow channel.

7. A shaftless impeller self-cooling canned motor pump according to claim 6, characterized in that: A lead-in port (101) is provided on the pump housing (10), and a lead-in port (201) on the stator (20) for connecting to an external power source passes through the pump housing (10) through the lead-in port (101).

8. The shaftless impeller self-cooling canned motor pump according to claim 7, characterized in that: Blades (32) are installed in the flow passage of the sleeve (31).

9. The shaftless impeller self-cooling canned motor pump according to claim 8, characterized in that: A spiral groove (212) is provided on the end surface of the rotor (21) facing the stator (20).

10. A shaftless impeller self-cooling canned motor pump according to claim 9, characterized in that: A diamond-like coating is provided at a position on the outer side of the sleeve (31) where it matches the bearing (23).

Images