Air-suspended centrifugal vacuum pump

Abstract

The utility model provides an air suspension centrifugal vacuum pump belongs to vacuum pump technical field, including pump body, air cooling flow channel and water cooling flow channel, pump body includes motor shell and rotating shaft, has opened the air outlet, liquid inlet and liquid outlet on the motor shell, air cooling flow channel includes air cooling volute inner chamber, thrust disc cooling flow channel, first buffer chamber, stator cooling flow channel and second buffer chamber that communicate in proper order, first buffer chamber and second buffer chamber are located at the both ends of rotor respectively, second buffer chamber communicates air outlet, water cooling flow channel is opened in the motor shell, and water cooling flow channel is spaced apart with air cooling flow channel, the utility model provides an air suspension centrifugal vacuum pump, carries out cooling to thrust bearing assembly and stator in proper order through air cooling flow channel, has solved the problem that stator, rotor heat dissipation is not good, has improved the cooling effect, and air cooling and water cooling cooperate, and the coolant can also indirectly assist cooling of low temperature air using the motor shell, improve the cooling effect of low temperature air.

Description

Technical Field

[0001] This utility model belongs to the field of vacuum pump technology, and more specifically, it relates to an air-suspended centrifugal vacuum pump. Background Technology

[0002] Magnetic levitation vacuum pumps are intelligent equipment developed using magnetic levitation bearing technology, high-speed permanent magnet motor technology, high-frequency vector frequency conversion technology, and high-efficiency fluid machinery technology. They are widely used in energy-saving retrofits of vacuum pump dewatering processes in the papermaking industry. However, during operation, the internal temperature of the magnetic levitation vacuum pump motor rises rapidly, and excessively high internal temperatures can affect the motor's lifespan.

[0003] To address the issue of excessively high internal temperatures in this motor, water cooling is commonly used in existing technologies. However, most existing water cooling structures only cool the exterior or a localized area of ​​the motor housing, resulting in a limited cooling range. This makes it difficult to directly cool the stator inside the motor housing, preventing the large amount of heat generated by the stator from being quickly transferred to the cooling water circuit and dissipated. Consequently, the overall internal temperature of the motor is too high, indirectly affecting the heat dissipation of components such as the rotor and bearings. Consequently, it fails to meet the high power and high heat dissipation requirements of the air-suspended turbine vacuum pump motor. Utility Model Content

[0004] The purpose of this invention is to provide an air-suspended centrifugal vacuum pump, which aims to solve the problems of high overall ambient temperature and poor heat dissipation performance inside the motor.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: to provide an air-suspended centrifugal vacuum pump, comprising: The pump body includes a motor housing and a rotating shaft. A main volute and an air-cooled volute are respectively located at both ends of the motor housing. The rotating shaft is located inside the motor housing. A first end of the rotating shaft extends into the main volute and is connected to a main impeller. A second end of the rotating shaft extends into the air-cooled volute and is sequentially connected to a thrust bearing assembly and an air-cooled impeller. The motor housing has an air outlet, a liquid inlet, and a liquid outlet. The air-cooled flow channel includes, in sequence, an air-cooled volute inner cavity, a thrust plate cooling flow channel, a first buffer cavity, a stator-rotor cooling flow channel, and a second buffer cavity; the first buffer cavity and the second buffer cavity are located at both ends of the rotor; the second buffer cavity is connected to the air outlet. A water-cooled flow channel is formed inside the motor housing, and the water-cooled flow channel and the air-cooled flow channel are spaced apart.

[0006] In another embodiment of this application, the thrust plate cooling channel further includes: The heat dissipation gap is located on the outer periphery of the thrust bearing assembly, and the heat dissipation gap connects the inner cavity of the air-cooled volute and the first buffer cavity.

[0007] In another embodiment of this application, the thrust plate cooling channel includes: The thrust plate cooling chamber is located between the outer thrust bearing seat and the inner thrust bearing seat of the thrust bearing assembly, and is arranged around the outer periphery of the thrust plate. An air inlet is provided on the outer thrust bearing seat, and the air inlet connects the inner cavity of the air-cooled volute and the cooling cavity of the thrust plate. An air vent is provided on the inner thrust bearing seat, and the air vent connects the thrust plate cooling chamber and the first buffer chamber.

[0008] In another embodiment of this application, the thrust plate cooling channel further includes: Multiple heat dissipation holes are radially distributed within the outer thrust bearing housing, and the heat dissipation holes connect the thrust plate cooling cavity and the air-cooled volute inner cavity.

[0009] In another embodiment of this application, the thrust plate cooling channel includes: A through hole extends axially through the thrust bearing assembly, and the through hole connects the inner cavity of the air-cooled volute and the first buffer cavity.

[0010] In another embodiment of this application, the stator and rotor cooling channels include: A rotor cooling channel is provided between the stator and the shaft, and the rotor cooling channel connects the first buffer chamber and the second buffer chamber; A stator cooling channel is provided between the stator and the motor housing; the stator cooling channel connects the first buffer cavity and the second buffer cavity.

[0011] In another embodiment of this application, the water-cooling channel is a spiral channel.

[0012] In another embodiment of this application, the second buffer cavity is located on one side of the radial bearing housing.

[0013] In another embodiment of this application, the air outlet is set at an angle to the radial direction of the motor housing.

[0014] The beneficial effects of the air-suspended centrifugal vacuum pump provided by this utility model are as follows: Compared with the prior art, the air-suspended centrifugal vacuum pump of this utility model sets the thrust bearing assembly on one side of the air-cooled impeller. While balancing the force on the shaft system structure, the low-temperature air first cools the thrust bearing assembly, improving the cooling effect of the thrust bearing assembly. The air-cooled flow channel sequentially cools the thrust bearing assembly and the stator and rotor, solving the problem of poor heat dissipation of the stator and rotor, and improving the cooling effect. Moreover, the combination of air cooling and water cooling allows the motor housing to be cooled by water cooling, while the coolant can also indirectly assist in cooling the low-temperature air passing through the first buffer chamber, the stator and rotor cooling flow channel, and the second buffer chamber through the motor housing, improving the cooling effect of the low-temperature air and solving the problem of high overall ambient temperature and poor heat dissipation performance inside the motor. This improves the operational stability of the entire vacuum pump, thereby improving the energy efficiency of the vacuum pump. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A schematic diagram of the structure of the air-suspended centrifugal vacuum pump provided in this embodiment of the utility model; Figure 2 A front view of an air-suspended centrifugal vacuum pump provided in an embodiment of this utility model; Figure 3 Rear view of the air-suspended centrifugal vacuum pump provided in an embodiment of this utility model; Figure 4 For along Figure 3 Sectional view of line AA in the middle; Figure 5 for Figure 4 Enlarged view at point M; Figure 6 A schematic diagram of the low-temperature airflow path of the thrust plate cooling channel provided for an embodiment of this utility model; Figure 7 A front view of the external thrust bearing housing provided in an embodiment of this utility model; Figure 8 For along Figure 7 Sectional view of the middle BB line; Figure 9 For along Figure 7 A cross-sectional view of the CC line.

[0017] In the diagram: 10. Motor housing; 11. Main volute; 12. End cover structure; 13. Liquid inlet; 14. Liquid outlet; 15. Air-cooled impeller; 16. External thrust bearing housing; 17. Internal thrust bearing housing; 18. Radial bearing housing; 19. Water-cooled flow channel; 20. Inner cavity of air-cooled volute; 21. Thrust plate cooling cavity; 22. Through hole; 23. Heat dissipation hole; 24. First buffer cavity; 25. Second buffer cavity; 26. Air outlet; 27. Buffer groove; 28. Air inlet; 29. ​​Mounting groove. Detailed Implementation

[0018] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0019] Please see Figures 1 to 9 The air suspension centrifugal vacuum pump provided by this utility model will now be described. The air-suspended centrifugal vacuum pump includes a pump body, an air-cooled flow channel, and a water-cooled flow channel 19. The pump body includes a motor housing 10 and a rotating shaft. The motor housing 10 has a main volute 11 and an air-cooled volute at its two ends, respectively. The rotating shaft is located inside the motor housing 10. The first end of the rotating shaft extends into the main volute 11 and is connected to a main impeller. The second end of the rotating shaft extends into the air-cooled volute and is connected to a thrust bearing assembly and an air-cooled impeller 15 in sequence. The motor housing 10 has an air outlet 26, a liquid inlet 13, and a liquid outlet 14. The air-cooled flow channel includes an air-cooled volute inner cavity 20, a thrust plate cooling flow channel, a first buffer chamber 24, a stator and rotor cooling flow channel, and a second buffer chamber 25, which are connected in sequence. The first buffer chamber 24 and the second buffer chamber 25 are located at the two ends of the rotor, respectively. The second buffer chamber 25 is connected to the air outlet 26. The water-cooled flow channel 19 is opened inside the motor housing 10 and is spaced apart from the air-cooled flow channel.

[0020] The air-suspended centrifugal vacuum pump provided by this utility model has a main impeller at one end of the rotating shaft and an air-cooled impeller 15 at the other end. The thrust bearing assembly is set on one side of the air-cooled impeller 15. By setting the thrust bearing assembly on one side of the air-cooled impeller 15, the weight and cantilever length of the main impeller side are reduced, the eccentricity of the rotor's center of mass is ensured, and the stability of the rotor shaft system is improved.

[0021] In addition, air-cooled channels and water-cooled channels 19 are provided inside the motor housing 10. When the air-cooled impeller 15 rotates, it draws in low-temperature air from the outside into the air-cooled volute cavity 20. The low-temperature air then flows through the thrust plate cooling channel to force-cool the thrust bearing assembly and prevent the bearing from overheating. Then, the low-temperature air enters the first buffer chamber 24, which is located at the end of the rotor near the air-cooled impeller 15. The first buffer chamber 24 can play a role in stabilizing the flow. Then, the low-temperature air continues to flow axially through the stator and rotor cooling channels to directly dissipate heat from the stator windings and rotor core. Finally, it enters the second buffer chamber 25 at the other end of the rotor and is discharged through the air outlet 26, forming a continuous air-cooling cycle.

[0022] Meanwhile, the water-cooled flow channel 19 operates independently within the motor housing 10. Coolant enters through the inlet 13, flows with the water-cooled flow channel 19, absorbs heat from the motor housing 10, and finally exits through the outlet 14. The water-cooled flow channel 19 is spaced apart from the air-cooled flow channel, and by cooling the motor housing 10, it assists in cooling the low-temperature air within the air-cooled flow channel, thus improving the overall cooling effect.

[0023] The air-cooled volute can also be equipped with an end cap structure 12.

[0024] Compared with the prior art, the air-suspended centrifugal vacuum pump provided by this utility model places the thrust bearing assembly on one side of the air-cooled impeller 15. While balancing the force on the shaft system structure, the low-temperature air first cools the thrust bearing assembly, improving the cooling effect of the thrust bearing assembly. The air-cooled flow channel sequentially cools the thrust bearing assembly and the stator and rotor, solving the problem of poor heat dissipation of the stator and rotor, and improving the cooling effect. Moreover, the combination of air cooling and water cooling allows the motor housing 10 to be cooled by water cooling, while the coolant can also indirectly assist in cooling the low-temperature air passing through the first buffer chamber 24, the stator and rotor cooling flow channel and the second buffer chamber 25 through the motor housing 10, improving the cooling effect of the low-temperature air and solving the problem of high overall ambient temperature and poor heat dissipation performance inside the motor. This improves the operational stability of the entire vacuum pump and thus improves the energy efficiency of the vacuum pump.

[0025] In some possible embodiments, please refer to Figure 4 , Figure 6 The thrust plate cooling channel also includes a heat dissipation gap, which is located on the outer periphery of the thrust bearing assembly and connects the ventilation cooling volute inner cavity 20 and the first buffer cavity 24.

[0026] The thrust bearing assembly is located between the air-cooled volute inner cavity 20 and the first buffer cavity 24, serving to separate the air-cooled volute inner cavity 20 and the first buffer cavity 24. After the thrust bearing assembly is installed with the air-cooled volute and the motor housing 10, a heat dissipation gap is formed between its outer periphery and the motor housing 10. When the pressure in the air-cooled volute inner cavity 20 increases, some low-temperature air can enter the first buffer cavity 24 through the heat dissipation gap. Here, the heat dissipation gap forms the first passage of the thrust plate cooling flow channel.

[0027] In some possible embodiments, please refer to Figures 4 to 9 The thrust plate cooling channel includes a thrust plate cooling cavity 21, an air inlet 28, and an air outlet. The thrust plate cooling cavity 21 is located between the outer thrust bearing housing 16 and the inner thrust bearing housing 17, and is arranged around the outer periphery of the thrust plate. The air inlet 28 is opened on the outer thrust bearing housing 16, and the air inlet 28 connects the ventilation and cooling volute inner cavity 20 and the thrust plate cooling cavity 21. The air outlet is opened on the inner thrust bearing housing 17, and the air outlet connects the thrust plate cooling cavity 21 and the first buffer cavity 24.

[0028] The thrust bearing assembly fitted on the side of the rotating shaft near the air-cooled impeller 15 includes an inner thrust bearing housing 17, a thrust plate, and an outer thrust bearing housing 16 installed sequentially along the axial direction, with the outer thrust bearing housing 16 on the side near the air-cooled impeller 15.

[0029] An installation groove 29 is provided at one end of the outer thrust bearing housing 16 near the inner thrust bearing housing 17. The opening of the installation groove 29 faces the inner thrust bearing housing 17 and is used to accommodate the thrust plate. During installation, the end face of the outer thrust bearing housing 16 fits against the end face of the inner thrust bearing housing 17 and is fixed by bolts or other structures. After installation, the installation groove 29 forms an annular cavity with the cooperation of the inner thrust bearing housing 17, and an annular thrust plate cooling cavity 21 is formed on the outer periphery of the thrust plate inside. This thrust plate cooling cavity 21 can cool the thrust plate and the inner and outer thrust bearing housings 17 and 16 on both sides of the thrust plate.

[0030] The outer thrust bearing housing 16 is located on the side close to the air-cooled impeller 15, and the side facing the air-cooled impeller 15 is the inner cavity of the air-cooled volute. An air inlet 28 is provided on the outer thrust bearing housing 16. The air inlet 28 is arranged along the thickness direction of the outer thrust bearing housing 16, with one end communicating with the inner cavity of the air-cooled volute and the other end communicating with the thrust plate cooling cavity 21. This allows the low-temperature air in the inner cavity 20 of the air-cooled volute to enter the thrust plate cooling cavity 21 through the air inlet 28 under the pressure of the air-cooled impeller 15.

[0031] The inner thrust bearing housing 17 is located on the side away from the air-cooled impeller 15, and this side is the first buffer chamber 24. An air outlet is provided on the inner thrust bearing housing 17, which is positioned along the thickness direction of the inner thrust bearing housing 17. One end of the outlet communicates with the thrust plate cooling chamber 21, and the other end communicates with the first buffer chamber 24. Low-temperature air entering the thrust plate cooling chamber 21 enters the first buffer chamber 24 through the air outlet.

[0032] The air inlet 28, the thrust plate cooling chamber 21, and the air outlet are connected in sequence to form the second passage of the thrust plate cooling flow channel.

[0033] In some possible embodiments, please refer to Figures 4 to 9 The thrust plate cooling channel also includes multiple heat dissipation holes 23, which are radially distributed in the outer thrust bearing seat 16 and connect the thrust plate cooling cavity 21 and the air-cooled volute inner cavity 20.

[0034] The heat dissipation hole 23 extends radially along the outer thrust bearing seat 16, with one end extending to the side wall of the mounting groove 29 and connecting to the thrust plate cooling cavity 21, and the other end extending to the outer side wall of the outer thrust bearing seat 16.

[0035] A buffer groove 27 is provided on the outer periphery of the outer thrust bearing housing 16 near the air-cooled impeller 15. The buffer groove 27 is connected to the inner cavity 20 of the air-cooled volute. The second end of the heat dissipation hole 23 extends into the buffer groove 27.

[0036] A portion of the low-temperature air entering the thrust plate cooling chamber 21 flows to the first buffer chamber 24 through the air outlet; the other portion enters the heat dissipation hole 23, which cools the outer thrust bearing seat 16 and the inner thrust bearing seat 17 through the heat dissipation hole 23 extending radially along the outer thrust bearing seat 16, and finally enters the buffer groove 27; the low-temperature air entering the buffer groove 27 merges with the low-temperature air in the air-cooled volute inner cavity 20 and flows backward to the first passage, that is, enters the first buffer chamber 24 through the heat dissipation gap.

[0037] The heat dissipation holes 23 can cool the outer thrust bearing housing 16 and the inner thrust bearing housing 17 located outside the thrust plate cooling chamber 21, thereby improving the overall cooling efficiency.

[0038] The pressure distribution in the air-cooled volute cavity 20 is high in the middle and low at the edges. Therefore, under the action of the air inlet 28, the air pressure in the thrust plate cooling cavity 21 is greater than the air pressure in the buffer groove 27. The low-temperature air in the thrust plate cooling cavity 21 can smoothly enter the heat dissipation hole 23 and enter the buffer groove 27 through the heat dissipation hole 23.

[0039] The air inlet 28, the thrust plate cooling chamber 21, the heat dissipation hole 23, the buffer groove 27, and the heat dissipation gap form the third passage of the thrust plate cooling flow channel.

[0040] In some possible embodiments, please refer to Figures 4 to 5 The thrust plate cooling channel includes a through hole 22, which axially penetrates the thrust bearing assembly and connects the ventilation and cooling volute cavity 20 and the first buffer cavity 24.

[0041] The through hole 22 passes through the outer thrust bearing housing 16 and the inner main thrust bearing housing in sequence, and the through hole 22 is spaced apart from the thrust plate cooling cavity 21, while the through hole 22 is spaced apart from the heat dissipation hole 23.

[0042] The through hole 22 directly connects the ventilation and cooling volute inner cavity 20 and the first buffer cavity 24, forming the fourth passage of the thrust plate cooling flow channel.

[0043] In some possible embodiments, please refer to Figure 4 , Figure 6 The rotor and stator cooling channels include a rotor cooling channel and a stator cooling channel; the rotor cooling channel is located between the stator and the shaft, and the rotor cooling channel connects the first buffer chamber 24 and the second buffer chamber 25; the stator cooling channel is located between the stator and the motor housing 10, and the stator cooling channel connects the first buffer chamber 24 and the second buffer chamber 25.

[0044] Under pressure, the low-temperature air in the first buffer chamber 24 is divided into two parts. The first part enters the rotor cooling channel to cool the shaft and the inner side of the stator; the second part enters the stator cooling channel to cool the outer side of the stator.

[0045] Since the stator cooling channel is located between the outside of the stator and the motor housing 10, the coolant inside the motor housing 10 cools the motor housing 10 while also assisting in cooling the air inside the stator cooling channel through the motor housing 10, thereby improving the cooling effect of air cooling on the stator.

[0046] In addition, since the first buffer chamber 24 and the second buffer chamber 25 are also located inside the motor housing 10, the air in the first buffer chamber 24 and the second buffer chamber 25 will also be cooled by the coolant in the motor housing 10.

[0047] Optionally, the water-cooling channel 19 located inside the motor housing 10 is a spiral channel.

[0048] In some possible embodiments, please refer to Figure 4 The second buffer cavity 25 is located on one side of the radial bearing housing 18.

[0049] Since the thrust bearing assembly is located at the end of the shaft near the air-cooled impeller 15, and the radial bearing housing 18 is located at the end of the shaft near the main impeller, the radial bearing housing 18 and the stator and rotor assembly inside the motor housing 10 cooperate to form a second buffer chamber 25. The low-temperature air in the second buffer chamber 25 can cool the stator and rotor while also cooling the radial bearing housing 18, thereby cooling the radial bearing.

[0050] Optionally, the air outlet 26 is connected to the second buffer chamber 25, and the air outlet 26 is set at an angle to the radial direction of the motor housing 10.

[0051] After the air carrying a large amount of heat gathers in the second buffer chamber 25, it flows towards the air outlet 26. Because the air outlet 26 forms an angle with the radial direction, the hot air is directed outwards, quickly moving away from the pump core area and being rapidly carried away by the surrounding air. Simultaneously, the angled design guides the airflow within the second buffer chamber 25, making the airflow smoother and more stable, reducing the air pressure within the second buffer chamber 25, creating a low-pressure zone. This creates a negative pressure suction effect on the front-end stator / rotor cooling channels and thrust plate cooling channels, enhancing the airflow rate throughout the entire air-cooled channel.

[0052] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An air-suspended centrifugal vacuum pump, characterized in that, include: The pump body includes a motor housing (10) and a rotating shaft. The motor housing (10) has a main volute (11) and an air-cooled volute at its two ends. The rotating shaft is located inside the motor housing (10). The first end of the rotating shaft extends into the main volute (11) and is connected to a main impeller. The second end of the rotating shaft extends into the air-cooled volute and is connected in sequence to a thrust bearing assembly and an air-cooled impeller (15). The motor housing (10) has an air outlet (26), a liquid inlet (13), and a liquid outlet (14). The air-cooled flow channel includes an air-cooled volute inner cavity (20), a thrust plate cooling flow channel, a first buffer cavity (24), a stator and rotor cooling flow channel, and a second buffer cavity (25) connected in sequence; the first buffer cavity (24) and the second buffer cavity (25) are located at both ends of the rotor; the second buffer cavity (25) is connected to the air outlet (26); A water-cooled flow channel (19) is provided inside the motor housing (10), and the water-cooled flow channel (19) is spaced apart from the air-cooled flow channel.

2. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The thrust plate cooling channel also includes: The heat dissipation gap is located on the outer periphery of the thrust bearing assembly and connects the air-cooled volute inner cavity (20) and the first buffer cavity (24).

3. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The thrust plate cooling channel includes: The thrust plate cooling chamber (21) is located between the outer thrust bearing seat (16) and the inner thrust bearing seat (17) of the thrust bearing assembly, and is arranged around the outer periphery of the thrust plate; An air inlet (28) is provided on the outer thrust bearing seat (16), and the air inlet (28) connects the air-cooled volute inner cavity (20) and the thrust plate cooling cavity (21). An air vent is provided on the inner thrust bearing seat (17), and the air vent is connected to the thrust plate cooling chamber (21) and the first buffer chamber (24).

4. The air-suspended centrifugal vacuum pump as described in claim 3, characterized in that, The thrust plate cooling channel also includes: Multiple heat dissipation holes (23) are radially distributed in the outer thrust bearing seat (16), and the heat dissipation holes (23) connect the thrust plate cooling cavity (21) and the air-cooled volute inner cavity (20).

5. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The thrust plate cooling channel includes: A through hole (22) extends axially through the thrust bearing assembly, and the through hole (22) connects the air-cooled volute inner cavity (20) and the first buffer cavity (24).

6. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The stator and rotor cooling channels include: A rotor cooling channel is provided between the stator and the shaft, and the rotor cooling channel connects the first buffer chamber (24) and the second buffer chamber (25); A stator cooling channel is provided between the stator and the motor housing (10); the stator cooling channel connects the first buffer chamber (24) and the second buffer chamber (25).

7. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The water-cooled flow channel (19) is a spiral flow channel.

8. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The second buffer cavity (25) is located on one side of the radial bearing housing (18).

9. The air-suspended centrifugal vacuum pump as described in claim 1, characterized in that, The air outlet (26) is set at an angle to the radial direction of the motor housing (10).

Images