An Axially Integrated Motor-Driven Centrifugal Pump and Its Control Method

Abstract

The present invention discloses a centrifugal pump driven by an axially integrated motor and a control method. The centrifugal pump includes a volute, an impeller, a drive unit, a filtering unit, a cooling unit and a control unit. The volute has a cavity, and the volute is provided with a suction port and a discharge port communicated with the cavity; the impeller is rotatably arranged in the cavity; the drive unit includes a main shaft, a permanent magnet group and a coil winding. The beneficial effects of the present invention are as follows: By adopting an integrated design of the motor and the pump body, the volume of the centrifugal pump can be reduced. The impurities in the fluid can be filtered by the first filter element, thereby protecting the permanent magnet group. The output power of the drive unit can be self-regulated according to the size of the fluid flow. When the temperature of the coil winding is too high, the drive unit stops automatically to avoid damage to the coil winding caused by excessive heat. The coil winding can be cooled by the cooling unit.

Description

Technical Field

[0001] The present invention relates to the technical field of centrifugal pumps, and particularly to a centrifugal pump driven by an axially integrated motor and a control method therefor. Background Art

[0002] A centrifugal pump mainly uses the centrifugal force generated by a high-speed rotating impeller to throw out the liquid, thereby realizing the transportation of the liquid.

[0003] Traditional centrifugal pumps work in a way that the motor drives the impeller. The impeller is inside the pump body while the motor is outside the pump body, and the two are connected by a transmission shaft. The centrifugal pump with this structure has a large volume. A small number of centrifugal pumps (such as an integrated motor-driven centrifugal pump disclosed in the application number 202310264997.0) adopt an integrated design of the motor and the pump body. Although the volume of the centrifugal pump can be reduced, when this centrifugal pump is applied to a fluid environment with more impurities, it cannot effectively protect the permanent magnet component inside the pump body. Moreover, the output power of the motor cannot be self-regulated according to the size of the fluid flow rate. When the fluid flow rate is small, it is easy to cause waste of energy. When the fluid flow rate is large, the centrifugal pump cannot meet the transportation requirements of the fluid. In addition, a large amount of heat is released during the operation of the motor. When the motor temperature is too high, the motor cannot stop automatically, and the excessive heat is likely to damage the motor, and there is no corresponding cooling mechanism to cool down the motor. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies, and propose a centrifugal pump driven by an axially integrated motor and a control method therefor, so as to solve the technical problems in the prior art that the centrifugal pump has a large volume, is not suitable for a fluid environment with more impurities, the output power of the motor cannot be self-regulated according to the size of the fluid flow rate, the motor cannot stop automatically when the temperature is too high, and there is no corresponding cooling mechanism to cool down the motor.

[0005] To achieve the above technical purpose, the technical solution of the present invention provides a centrifugal pump driven by an axially integrated motor, including:

[0006] A volute having a cavity, and an inlet and an outlet communicating with the cavity are provided on the volute;

[0007] An impeller rotatably arranged in the cavity;

[0008] A driving unit including a main shaft, a permanent magnet group and a coil winding. The main shaft is rotatably arranged in the cavity along the axial direction of the volute and is coaxially fixed to the impeller. The permanent magnet group is arranged in the cavity and is coaxially fixed to the main shaft. The coil winding is fixed to the volute and corresponds to the permanent magnet group;

[0009] A filtering unit, which includes a first filter element disposed in the cavity and located between the impeller and the permanent magnet group;

[0010] A cooling unit for cooling the coil winding;

[0011] A regulation unit for monitoring the pressure in the cavity and the temperature of the coil winding, and adjusting the magnitude of the current passing through the coil winding.

[0012] Furthermore, the volute includes a housing body, an end cover, a suction pipe, a discharge pipe and two flanges. The housing body forms the cavity therein. Both axial ends of the cavity are open. The end cover is detachably fixed to one end of the cavity to seal the opening at one end of the cavity. The suction pipe is axially disposed at the other end of the housing body along the cavity. One end of the suction pipe communicates with the opening at the other end of the cavity. The other end of the suction pipe forms the suction port. The discharge pipe is tangentially disposed at the side of the housing body along the cavity. One end of the discharge pipe communicates with the cavity. The other end of the discharge pipe forms the discharge port. The two flanges are respectively fixedly sleeved on the other ends of the corresponding suction pipe and discharge pipe.

[0013] Furthermore, the permanent magnet group is disposed between the end cover and the impeller. The permanent magnet group includes a rotor and a plurality of permanent magnets. The rotor is of a disc structure and is detachably and fixedly sleeved on the main shaft. A plurality of receiving grooves are formed on the side wall of the rotor facing the end cover. Each of the permanent magnets is detachably disposed in the corresponding receiving groove.

[0014] Furthermore, the coil winding includes a stator and a coil. The stator has a receiving cavity with one side open. The opening side of the receiving cavity faces the end cover. The stator is detachably and fixedly connected to the end cover. The coil is disposed in the receiving cavity and wound around the stator. The coil is electrically connected to a power source.

[0015] Furthermore, the first filter element includes a housing and a plurality of disc plates. The housing is of a funnel-shaped structure and has a filtering cavity of a funnel-shaped structure. Both axial ends of the filtering cavity are open. The outer side wall of the housing is fixedly connected to the inner side wall of the cavity. Each of the disc plates is of an annular structure and is rotatably and sealedly disposed at intervals along the axis of the filtering cavity. Each of the disc plates is also fixedly sleeved on the main shaft. A plurality of filtering holes are formed on each of the disc plates.

[0016] Furthermore, the filtering unit further includes a second filter element disposed at the suction port for filtering impurities entering the suction port.

[0017] Further, the cooling unit includes a cooling pipe and a plurality of heat sinks. The cooling pipe has a serpentine structure and is wound around the outer sidewall of the stator in a spiral manner. One end of the cooling pipe is close to the suction port to form an inlet, and the other end of the cooling pipe is far from the suction port to form an outlet. Each of the heat sinks is disposed in the gap between adjacent cooling pipes and is fixedly provided on the outer sidewall of the stator.

[0018] Further, the distance between adjacent pipe segments of the cooling pipe at the middle part of the stator is smaller than the distance between adjacent pipe segments of the cooling pipe at both ends of the stator. The pipe diameter at the inlet of the cooling pipe and the pipe diameter at the outlet are both larger than the pipe diameter at the middle section of the cooling pipe.

[0019] Further, the control unit includes a data acquisition mechanism, a data processing mechanism, an adjustment mechanism, and a data display mechanism. The data acquisition mechanism includes a pressure sensor and a temperature sensor. The pressure sensor is disposed in the cavity to collect the pressure in the cavity, judge the fluid flow rate according to the pressure magnitude, and convert the pressure signal into an electrical signal. The temperature sensor is disposed on the outer sidewall of the stator to collect the temperature on the outer surface of the stator and convert the temperature signal into an electrical signal. The data processing mechanism is a central processing unit. The central processing unit is used to receive and process the electrical signals from the pressure sensor and the temperature sensor and issue instructions. When the pressure in the cavity is small, it indicates that the fluid flow rate in the cavity is small, and the current magnitude passing through the coil is reduced, the magnetic field intensity generated by the coil is weakened, and the rotation speed of the rotor is reduced. When the pressure in the cavity is large, it indicates that the fluid flow rate in the cavity is large, and the current magnitude passing through the coil is increased, the magnetic field intensity generated by the coil is enhanced, and the rotation speed of the rotor is increased. When the temperature of the stator reaches the preset temperature, the current magnitude passing through the coil is zero, the magnetic field intensity generated by the coil is zero, and the rotation speed of the rotor is zero. The adjustment mechanism includes a current sensor and a rotation speed sensor. The current sensor is disposed in the circuit connecting the coil and the power supply. The rotation speed sensor is disposed on the rotor. The current sensor and the rotation speed sensor are both used to receive the instructions issued by the central processing unit and adjust the current magnitude through the circuit sensor and adjust the rotation speed of the rotor through the rotation speed sensor. The data display mechanism is a display screen, and the display screen is used to display pressure and temperature information.

[0020] The present invention also provides a control method for a centrifugal pump driven by an axial integrated motor, which is applicable to the centrifugal pump driven by the axial integrated motor as described above, and includes the following steps:

[0021] The control unit monitors the pressure in the cavity and the temperature of the coil winding;

[0022] When the pressure in the cavity is small, it indicates that the fluid flow rate in the cavity is small. The regulation unit reduces the magnitude of the current passing through the coil winding, the magnetic field strength generated by the coil winding weakens, and the rotation speed of the permanent magnet group decreases;

[0023] When the pressure in the cavity is large, it indicates that the fluid flow rate in the cavity is large. The regulation unit increases the magnitude of the current passing through the coil winding, the magnetic field strength generated by the coil winding increases, and the rotation speed of the permanent magnet group increases;

[0024] When the temperature of the coil winding reaches the preset temperature, the regulation unit adjusts the magnitude of the current passing through the coil winding to zero, the magnetic field strength generated by the coil winding is zero, and the rotation speed of the permanent magnet group is zero.

[0025] Compared with the prior art, the beneficial effects of the present invention include: This centrifugal pump adopts an integrated design of the motor and the pump body, which can reduce the volume of the centrifugal pump. When this centrifugal pump is used in a fluid environment with more impurities, the first filter element can filter the impurities in the fluid, thereby protecting the permanent magnet group. The output power of the drive unit can be self-regulated according to the magnitude of the fluid flow rate. When the fluid flow rate is small, the output power of the drive unit decreases, avoiding waste of energy. When the fluid flow rate is large, the output power of the drive unit increases, enabling the centrifugal pump to meet the fluid transportation requirements. In addition, a large amount of heat is released during the operation of the coil winding. When the temperature of the coil winding is too high, the regulation unit adjusts the magnitude of the current passing through the coil winding to zero, the magnetic field strength generated by the coil winding is zero, the rotation speed of the permanent magnet group is zero, and the drive unit realizes self-stop, avoiding damage to the coil winding caused by excessive heat. The coil winding can be cooled by the cooling unit. Description of the Drawings

[0026] Figure 1 is a three-dimensional structural schematic diagram of a centrifugal pump driven by an axially integrated motor provided by the present invention;

[0027] Figure 2 is Figure 1 a sectional view of a centrifugal pump driven by an axially integrated motor in

[0028] Figure 3 is Figure 2 a sectional view of the suction pipe of a centrifugal pump driven by an axially integrated motor in

[0029] Figure 4 is a three-dimensional structural schematic diagram of the impeller of a centrifugal pump driven by an axially integrated motor provided by the present invention;

[0030] Figure 5 is Figure 4Schematic diagram of the blade structure of the impeller in

[0031] Figure 6 is a three-dimensional structural schematic diagram of a centrifugal pump rotor driven by an axially integrated motor provided by the present invention;

[0032] Figure 7 is a cross-sectional view of a first filter element of a centrifugal pump driven by an axially integrated motor provided by the present invention;

[0033] Figure 8 is a three-dimensional structural schematic diagram of a cooling unit of a centrifugal pump driven by an axially integrated motor provided by the present invention;

[0034] Figure 9 is a schematic diagram of the principle of a control method for a centrifugal pump driven by an axially integrated motor provided by the present invention;

[0035] In the figure: 100 - volute, 110 - cavity, 120 - suction port, 130 - discharge port, 140 - housing body, 150 - end cover, 160 - suction pipe, 170 - discharge pipe, 180 - flange, 200 - impeller, 210 - shaft sleeve, 220 - front side plate, 230 - rear side plate, 240 - blade, 300 - drive unit, 310 - main shaft, 320 - permanent magnet group, 321 - rotor, 3211 - receiving groove, 330 - coil winding, 331 - stator, 3311 - receiving cavity, 400 - filter unit, 410 - first filter element, 411 - housing, 4111 - filter cavity, 412 - disc, 4121 - filter hole, 4122 - clamping groove, 420 - second filter element, 500 - cooling unit, 510 - cooling pipe, 600 - base. Detailed implementation manners

[0036] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention 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 only used to explain the present invention and are not used to limit the present invention.

[0037] The present invention provides a centrifugal pump driven by an axially integrated motor, and its structure is as Figure 1 - Figure 8As shown in the figure, it includes a volute 100, an impeller 200, a drive unit 300, a filtration unit 400, a cooling unit 500 and a regulation unit. The volute 100 has a cavity 110, and an air inlet 120 and an air outlet 130 communicating with the cavity 110 are provided on the volute 100; the impeller 200 is rotatably arranged in the cavity 110; the drive unit 300 includes a main shaft 310, a permanent magnet group 320 and a coil winding 330. The main shaft 310 is rotatably arranged in the cavity 110 along the axial direction of the volute 100 and is coaxially fixed to the impeller 200. The permanent magnet group 320 is arranged in the cavity 110 and is coaxially fixed to the main shaft 310. The coil winding 330 is fixed to the volute 100 and corresponds to the permanent magnet group 320; the filtration unit 400 includes a first filter element 410, which is arranged in the cavity 110 and is located between the impeller 200 and the permanent magnet group 320; the cooling unit 500 is used to cool the coil winding 330; the regulation unit is used to monitor the pressure in the cavity 110 and the temperature of the coil winding 330, and adjust the magnitude of the current passing through the coil winding 330.

[0038] During use, the coil winding 330 is energized. When the coil winding 330 is energized, a magnetic field will be generated. This magnetic field will interact with the magnetic field of the permanent magnet group 320. When the coil winding 330 is energized to become an electromagnet, N and S poles will appear. The N and S poles of the permanent magnet group 320 are fixed. According to the principle of like poles repelling and opposite poles attracting, the S pole of the permanent magnet group 320 will be attracted by the N pole of the coil winding 330, and the N pole of the permanent magnet group 320 will be repelled by the N pole of the coil winding 330. In this way, a tangential force component is formed, which drives the permanent magnet group 320 to rotate and drives the main shaft 310 to rotate. During the rotation of the main shaft 310, the impeller 200 will be driven to rotate. The centrifugal force generated by the high-speed rotating impeller 200 throws out the liquid, thus realizing the transportation of the liquid. The first filter element 410 can filter impurities in the fluid to prevent the impurities in the fluid from damaging the permanent magnet group 320, and the regulation unit can monitor the pressure in the cavity 110 and the temperature of the coil winding 330. When the pressure in the cavity 110 is small, it indicates that the fluid flow rate in the cavity 110 is small. The regulation unit reduces the magnitude of the current passing through the coil winding 330, the magnetic field strength generated by the coil winding 330 weakens, and the rotation speed of the permanent magnet group 320 decreases. When the pressure in the cavity 110 is large, it indicates that the fluid flow rate in the cavity 110 is large. The regulation unit increases the magnitude of the current passing through the coil winding 330, the magnetic field strength generated by the coil winding 330 increases, and the rotation speed of the permanent magnet group 320 increases. When the temperature of the coil winding 330 reaches the preset temperature, the regulation unit adjusts the magnitude of the current passing through the coil winding 330 to zero, the magnetic field strength generated by the coil winding 330 is zero, and the rotation speed of the permanent magnet group 320 is zero. In this centrifugal pump, the integrated design of the motor and the pump body is adopted, which can reduce the volume of the centrifugal pump. When this centrifugal pump is used in a fluid environment with more impurities, the first filter element 410 can filter impurities in the fluid to protect the permanent magnet group 320. The output power of the drive unit 300 can be self-regulated according to the magnitude of the fluid flow rate. When the fluid flow rate is small, the output power of the drive unit 300 decreases to avoid wasting energy. When the fluid flow rate is large, the output power of the drive unit 300 increases to enable the centrifugal pump to meet the fluid transportation requirements. In addition, a large amount of heat will be released during the operation of the coil winding 330. When the temperature of the coil winding 330 is too high, the regulation unit adjusts the magnitude of the current passing through the coil winding 330 to zero, the magnetic field strength generated by the coil winding 330 is zero, the rotation speed of the permanent magnet group 320 is zero, and the drive unit 300 realizes self-stopping to avoid damage to the coil winding 330 caused by excessive heat.The coil winding 330 can be cooled by the cooling unit 500.

[0039] As a preferred embodiment, please refer to Figure 1 and Figure 2 , the suction port 120 is axially formed along the cavity 110, the discharge port 130 is radially formed along the cavity 110. When the impeller 200 rotates at a high speed, a negative pressure environment and a centrifugal force will be generated, sucking the fluid from the suction port 120 and discharging it from the discharge port 130.

[0040] As a preferred embodiment, please refer to Figure 1 and Figure 2 , the volute 100 includes a housing body 140, an end cover 150, a suction pipe 160, a discharge pipe 170 and two flanges 180. The cavity 110 is formed inside the housing body 140. Both ends of the cavity 110 in the axial direction are open. The end cover 150 is detachably fixed to one end of the cavity 110 to seal the opening at one end of the cavity 110. The suction pipe 160 is axially arranged at the other end of the housing body 140 along the cavity 110. One end of the suction pipe 160 is communicated with the opening at the other end of the cavity 110, and the other end of the suction pipe 160 forms the suction port 120. The discharge pipe 170 is tangentially arranged at the side of the housing body 140 along the cavity 110. One end of the discharge pipe 170 is communicated with the cavity 110, and the other end of the discharge pipe 170 forms the discharge port 130. The two flanges 180 are respectively fixedly sleeved on the other ends of the corresponding suction pipe 160 and the discharge pipe 170. This structure of the volute 100 can reduce the volume of the volute 100 and also facilitate the installation of the permanent magnet group 320 arranged in the cavity 110 and the replacement of the first filter element 410 arranged in the cavity 110.

[0041] As a preferred embodiment, please refer to Figure 4 and Figure 5, the impeller 200 includes a shaft sleeve 210, a front side plate 220, a rear side plate 230 and a plurality of blades 240. The shaft sleeve 210 is fixedly sleeved on the main shaft 310. The front side plate 220 and the rear side plate 230 are both annular structures and are both spaced apart and coaxially sleeved on the shaft sleeve 210. The inner ring diameter of the front side plate 220 is larger than the diameter of the shaft sleeve 210. A gap between the inner side wall of the front side plate 220 and the outer side wall of the shaft sleeve 210 forms a liquid inlet, and the liquid inlet is communicated with the suction port 120. The inner ring diameter of the rear side plate 230 is equal to the diameter of the shaft sleeve 210 and is fixedly connected to the shaft sleeve 210. Each of the blades 240 is disposed between the front side plate 220 and the rear side plate 230 and is circumferentially distributed on the side of the shaft sleeve 210. Both sides of each of the blades 240 are fixedly connected to the front side plate 220 and the rear side plate 230. A gap between adjacent blades 240 forms a liquid outlet, and the liquid outlet is communicated with the cavity 110. The impeller 200 adopts a bionic design structure. The impeller 200 is made of HDR duplex stainless steel material, and the outer surface of the impeller 200 is subjected to plastic coating treatment, effectively avoiding cavitation of the impeller 200 in the use environment.

[0042] As a preferred embodiment, please refer to Figure 5 , the surface of the blade 240 is a fish-scale structure, with higher wear resistance and longer service life. The blade 240 stirs the fluid to generate less bubbles, effectively reducing the noise generated when the centrifugal pump works, achieving the effect of reducing noise pollution. At the same time, the bionic structure of the blade 240 can enhance the suction force of the impeller 200 on the fluid, improve the working efficiency of the impeller 200, and reduce unnecessary energy waste.

[0043] As a preferred embodiment, please refer to Figure 2 and Figure 6, the permanent magnet group 320 is arranged between the end cover 150 and the impeller 200. The permanent magnet group 320 includes a rotor 321 and a plurality of permanent magnets. The rotor 321 is of a disc structure and is detachably and fixedly sleeved on the main shaft 310. A plurality of receiving grooves 3211 are formed in the side wall of the rotor 321 facing the end cover 150, and each of the permanent magnets is detachably arranged in a corresponding receiving groove 3211, which can reduce the volume of the permanent magnet group 320. When the permanent magnet group 320 is integrated into the cavity 110, the overall volume of the centrifugal pump is reduced, the space occupied by the centrifugal pump is reduced, and it is convenient to operate in a narrow space. A plurality of the permanent magnets are embedded in the rotor 321 with a disc structure, and the rotor 321 is sealed. The rotor 321 is made of MP-35 alloy material, and the rotor 321 has the advantages of high hardness, non-magnetism, good ductility, and cavitation resistance. Each of the permanent magnets is arranged in a corresponding receiving groove 3211 by a clamping method, which makes the disassembly and assembly of the permanent magnets more convenient and can also prevent the permanent magnets from falling off during high-speed operation, ensuring the stability of the operation of the permanent magnet group 320. After the rotor 321 is installed, it is immersed in the fluid so that the rotor 321 can be fully cooled. The rotor 321 adopts an organic silicone waterproof technology and has good waterproofness and heat resistance. The rotor 321 is suitable for working requirements in a fluid environment and high-speed operation. The design of spiral stripes on the outer surface of the rotor 321 reduces the resistance of the rotor 321 during operation in a fluid environment. At the same time, using MP-35 alloy as a protective shell extends the service life of the workpiece, prevents the rotor 321 from being damaged, and improves work safety.

[0044] As a preferred embodiment, please refer to Figure 6 , each of the receiving grooves 3211 is of a fan-shaped structure and is circumferentially arranged. Each of the permanent magnets is of a fan-shaped structure, and the arrangement of the permanent magnets conforms to the Halbach array, maximizing the reasonable saving of the permanent magnets.

[0045] As a preferred embodiment, please refer to Figure 2, the coil winding 330 includes a stator 331 and a coil. The stator 331 has a receiving cavity 3311 with an open side. The open side of the receiving cavity 3311 faces the end cover 150. The stator 331 is detachably and fixedly connected to the end cover 150. The coil is disposed in the receiving cavity 3311 and wound around the stator 331. The coil is electrically connected to a power source, facilitating the removal of the stator 331 from the end cover 150 and then the removal of the end cover 150 from the housing body 140. Since the rotor 321 and the permanent magnet are both installed in the cavity 110, and the stator 331 and the coil are installed outside the volute 100, and the coil and the permanent magnet are not in the same cavity 110, in order to avoid affecting the strength of the magnetic force, the material for making the end cover 150 needs to eliminate this influence.

[0046] As a preferred embodiment, please refer to Figure 2 and Figure 7 , the first filter element 410 includes a housing 411 and a plurality of discs 412. The housing 411 is in a funnel-shaped structure and has a filtering cavity 4111 in a funnel-shaped structure. Both axial ends of the filtering cavity 4111 are open. The outer side wall of the housing 411 is fixedly connected to the inner side wall of the cavity 110. Each of the discs 412 is in a ring structure and is rotatably and sealedly disposed in the filtering cavity 4111 at intervals along the axis of the filtering cavity 4111. Each of the discs 412 is also fixedly sleeved on the main shaft 310. A plurality of filtering holes 4121 are formed in each of the discs 412, which can achieve the separation of fluid and impurities. The impurities in the fluid are filtered by each of the discs 412, thereby protecting the rotor 321 and preventing small impurity debris from entering and causing wear to the rotor 321. The fluid can cool the rotor 321, and the impurities need to be cleaned manually by regularly disassembling the pump body.

[0047] As a preferred embodiment, please refer to Figure 2 , the small opening of the filtering cavity 4111 faces the impeller 200, and the large opening of the filtering cavity 4111 faces the rotor 321, so as to facilitate the removal of each of the discs 412 from the filtering cavity 4111 after removing the end cover 150.

[0048] As a preferred embodiment, please refer to Figure 2 and Figure 7, the outer wall of the housing 411 is detachably fixed to the inner wall of the cavity 110 via screws. The first filter element 410 further includes a rail, which is fixedly arranged on the main shaft 310 along the length direction of the main shaft 310. Each of the discs 412 is provided with a card slot 4122 and is clamped on the rail via the card slot 4122, so that each of the discs 412 can be removed from the main shaft 310, facilitating the cleaning or replacement of each of the discs 412.

[0049] As a preferred embodiment, please refer to Figure 2 and Figure 3 , the filtering unit 400 further includes a second filter element 420, which is arranged at the suction port 120 for filtering impurities entering the suction port 120 to protect the impeller 200 and improve the protection effect on the rotor 321.

[0050] As a preferred embodiment, please refer to Figure 3 , the second filter element 420 is a magnetic collar, which is fixedly arranged on the inner wall of the suction pipe 160. The collar can adsorb metal impurities in the fluid, which can protect the impeller 200 and also protect the permanent magnet.

[0051] As a preferred embodiment, please refer to Figure 8 , the cooling unit 500 includes a cooling pipe 510 and a plurality of heat sinks. The cooling pipe 510 is in a serpentine structure and is wound around the outer wall of the stator 331 in a spiral manner. One end of the cooling pipe 510 is close to the suction port 120 to form an inlet, and the other end of the cooling pipe 510 is far from the suction port 120 to form an outlet. Each of the heat sinks is respectively arranged in the gap between adjacent cooling pipes 510 and is fixedly arranged on the outer wall of the stator 331. When the coil winding 330 is energized, the fluid enters the cavity 110 due to the suction force generated by the rotation of the impeller 200. Part of the fluid enters the cooling pipe 510 along the inlet and cools the stator 331, and finally is discharged to the low-pressure area of the volute 100 through the outlet. The cooling pipe 510 effectively uses the fluid to cool the stator 331, has strong cooling ability, can achieve rapid heat dissipation, ensure the safety and stability of the equipment, and moreover, the cooling pipe 510 and the heat sinks are coupled to cool the stator 331, which improves the cooling efficiency, reduces the noise during cooling, provides a better working environment for the staff, and can greatly reduce the cooling cost of the stator 331.

[0052] As a preferred embodiment, the spacing between adjacent pipe segments of the cooling pipe 510 at the middle part of the stator 331 is smaller than the spacing between adjacent pipe segments of the cooling pipe 510 at both ends of the stator 331. The pipe diameter at the inlet of the cooling pipe 510 and the pipe diameter at the outlet are both larger than the pipe diameter at the middle section of the cooling pipe 510, which can effectively slow down the flow velocity of the fluid in the cooling pipe 510 and enhance the cooling effect.

[0053] As a preferred embodiment, please refer to Figure 1 and Figure 2 , the centrifugal pump driven by the axially integrated motor further includes a base 600. The housing 140 and the stator 331 are both fixedly arranged on the base 600, and the housing 140 and the stator 331 can be supported by the base 600.

[0054] As a preferred embodiment, please refer to Figure 9, the control unit includes a data acquisition mechanism, a data processing mechanism, an adjustment mechanism, and a data display mechanism. The data acquisition mechanism includes a pressure sensor and a temperature sensor. The pressure sensor is disposed in the cavity 110 for collecting the pressure in the cavity 110, judging the fluid flow rate according to the pressure magnitude, and converting the pressure signal into an electrical signal. The temperature sensor is disposed on the outer sidewall of the stator 331 for collecting the temperature on the outer surface of the stator 331 and converting the temperature signal into an electrical signal. The data processing mechanism includes a central processor, which is used for receiving and processing the electrical signals of the pressure sensor and the temperature sensor and issuing instructions. When the pressure in the cavity 110 is small, it indicates that the fluid flow rate in the cavity 110 is small, and the magnitude of the current passing through the coil is reduced, the magnetic field intensity generated by the coil is weakened, and the rotation speed of the rotor 321 is reduced. When the pressure in the cavity 110 is large, it indicates that the fluid flow rate in the cavity 110 is large, and the magnitude of the current passing through the coil is increased, the magnetic field intensity generated by the coil is enhanced, and the rotation speed of the rotor 321 is increased. When the temperature of the stator 331 reaches the preset temperature, the magnitude of the current passing through the coil is zero, the magnetic field intensity generated by the coil is zero, and the rotation speed of the rotor 321 is zero. The adjustment mechanism includes a current sensor and a rotation speed sensor. The current sensor is disposed in the circuit connecting the coil and the power supply, and the rotation speed sensor is disposed on the rotor 321. Both the current sensor and the rotation speed sensor are used for receiving the instructions issued by the central processor and adjusting the magnitude of the current through the circuit sensor and adjusting the rotation speed of the rotor 321 through the rotation speed sensor. The data display mechanism is a display screen, which is used for displaying pressure and temperature information, thereby realizing intelligent drive, realizing self-regulation of the output power of the drive unit 300, and self-stopping of the drive unit 300 under high-temperature conditions.

[0055] As a preferred embodiment, both the rotor 321 and the rotation speed sensor adopt an organic silicone waterproof technology. First, potting and encapsulation treatment is carried out with an organic silicone adhesive. Secondly, the rotor 321 and the rotation speed sensor are arranged and fixed on the respective frames by using an MP-35 alloy thin plate and are fixed by potting with a silicone insulating medium. Finally, a nano-modified organosilicon rubber waterproof coating is applied to the surface of the MP-35 alloy and neutralizes with the sealing properties of the previous layers, wherein the MP-35 alloy thin plate (2012) has internal ribs for fixed installation and special streamline textures are arranged on the surface.

[0056] As a preferred embodiment, please refer to Figure 9, the data acquisition mechanism further includes a noise sensor disposed on the main shaft 310 for collecting the noise decibel data generated by the rotation of the main shaft 310. The central processor is used to receive and process the data collected by the noise sensor to judge the wear degree of the bearing of the main shaft 310. The display screen is used to display the wear degree information, which can effectively detect the working state of the centrifugal pump and reduce the possibility of accidents during the operation of the centrifugal pump.

[0057] As a preferred embodiment, please refer to Figure 9 , the data acquisition mechanism further includes a vibration sensor disposed on the base 600 for collecting the data of the vibration frequency of the centrifugal pump. The central processor is used to receive and process the data collected by the vibration sensor and issue an instruction. When the real-time vibration frequency of the centrifugal pump conflicts with the normal vibration range of the centrifugal pump, the current magnitude through the coil is zero, and the rotational speed of the rotor 321 is zero. The display screen is used to display the vibration frequency information, which can effectively detect the working state of the centrifugal pump and reduce the possibility of accidents during the operation of the centrifugal pump.

[0058] As a preferred embodiment, please refer to Figure 9 , the data acquisition mechanism further includes a timer. The timer adopts an accumulative timing method. When the coil is energized, the timing starts, and when the coil is de-energized, the timing stops. The timing duration is stored and accumulated. The display screen is used to display the total working duration information of the centrifugal pump, which can effectively detect the working state of the centrifugal pump and reduce the possibility of accidents during the operation of the centrifugal pump.

[0059] The present invention also provides a control method for an axially integrated motor-driven centrifugal pump, which is applicable to the above-mentioned axially integrated motor-driven centrifugal pump and includes the following steps:

[0060] The pressure sensor monitors the pressure in the cavity 110, judges the fluid flow rate according to the pressure magnitude, and converts the pressure signal into an electrical signal. The temperature sensor monitors the temperature of the stator 331 and converts the temperature signal into an electrical signal;

[0061] The central processor is used to receive and process the electrical signals of the pressure sensor and the temperature sensor and issue an instruction;

[0062] When the pressure in the cavity 110 is small, it indicates that the fluid flow rate in the cavity 110 is small. The control unit reduces the magnitude of the current passing through the coil, the magnetic field intensity generated by the coil weakens, and the rotational speed of the rotor 321 decreases;

[0063] When the pressure in the cavity 110 is relatively high, it indicates that the fluid flow rate in the cavity 110 is relatively large. The regulation unit increases the magnitude of the current passing through the coil, the magnetic field intensity generated by the coil is enhanced, and the rotational speed of the rotor 321 increases;

[0064] When the temperature of the stator 331 reaches the preset temperature, the magnitude of the current passing through the coil is zero, the magnetic field intensity generated by the coil is zero, and the rotational speed of the rotor 321 is zero;

[0065] The current sensor is used to receive the instruction issued by the central processing unit and adjust the magnitude of the current. The rotational speed sensor is used to receive the instruction issued by the data processing mechanism and adjust the rotational speed of the rotor 321;

[0066] The display screen is used to display pressure and temperature information.

[0067] For a better understanding of the present invention, the following combines Figure 1 - Figure 9 to elaborate in detail on the working principle of the technical solution of the present invention:

[0068] During use, the coil is energized. When the coil is energized, a magnetic field is generated. This magnetic field will interact with the magnetic field of the permanent magnet. When the coil is energized to become an electromagnet, N and S poles will appear, while the N and S poles of the permanent magnet are fixed. According to the principle of like poles repelling and opposite poles attracting, the S pole of the permanent magnet will be attracted by the N pole of the coil, and the N pole of the permanent magnet will be repelled by the N pole of the coil. In this way, a tangential force component is formed, which drives the rotation of the rotor 321 and drives the rotation of the main shaft 310. During the rotation of the main shaft 310, it will drive the rotation of the impeller 200. The centrifugal force generated by the high-speed rotating impeller 200 throws the liquid out, thereby realizing the transportation of the liquid. Through each disc 412 in the first filter 410, impurities in the fluid can be filtered, thereby protecting the rotor 321 and preventing fine impurity debris from entering and causing wear to the rotor 321. The fluid can cool the rotor 321. The pressure in the cavity 110 is monitored by the pressure sensor and the pressure signal is converted into an electrical signal. The temperature of the stator 331 is monitored by the temperature sensor and the temperature signal is converted into an electrical signal. When the pressure in the cavity 110 is small, it indicates that the fluid flow rate in the cavity 110 is small. The current sensor reduces the current magnitude passing through the coil, and the magnetic field intensity generated by the coil weakens. The rotation speed sensor reduces the rotation speed of the rotor 321. When the pressure in the cavity 110 is large, it indicates that the fluid flow rate in the cavity 110 is large. The current sensor increases the current magnitude passing through the coil, and the magnetic field intensity generated by the coil increases. The rotation speed sensor increases the rotation speed of the rotor 321. When the temperature of the stator 331 reaches the preset temperature, the current sensor adjusts the current magnitude passing through the coil to zero, and the magnetic field intensity generated by the coil is zero. The rotation speed sensor adjusts the rotation speed of the rotor 321 to zero. This centrifugal pump adopts an integrated design of the motor and the pump body, which can reduce the volume of the centrifugal pump. When this centrifugal pump is used in a fluid environment with more impurities, impurities in the fluid can be filtered through each disc 412 in the first filter 410, thereby protecting the rotor 321. The metal impurities in the fluid can be adsorbed through the collar, which can protect the impeller 200 and also protect the permanent magnet. The cooling pipe 510 effectively utilizes the fluid to cool the stator 331, and has strong cooling ability, which can achieve rapid heat dissipation and ensure the safety and stability of the equipment. The output power of the drive unit 300 can be self-adjusted according to the magnitude of the fluid flow rate. When the fluid flow rate is small, the output power of the drive unit 300 decreases, avoiding waste of energy. When the fluid flow rate is large, the output power of the drive unit 300 increases, enabling the centrifugal pump to meet the fluid transportation requirements. In addition,The coil releases a lot of heat during operation. When the temperature of the stator 331 is too high, the current through the coil is adjusted to zero, the magnetic field strength generated by the coil is zero, the speed of the rotor 321 is zero, and the drive unit 300 stops automatically to avoid damage to the coil winding 330 caused by excessive heat.

[0069] The present invention provides an axially integrated motor-driven centrifugal pump and a control method thereof, which have the following beneficial effects:

[0070] (1) The centrifugal pump adopts an integrated design of the motor and the pump body, which can reduce the volume of the centrifugal pump. When the centrifugal pump is used in a fluid environment containing a lot of impurities, the impurities in the fluid can be filtered through each of the discs 412 in the first filter element 410, thereby protecting the rotor 321. The metal impurities in the fluid can be adsorbed by the collar, which can protect the impeller 200 and the permanent magnet.

[0071] (2) The cooling pipe 510 effectively uses fluid to cool the stator 331, has a strong cooling capacity, can achieve rapid heat dissipation, and ensure the safety and stability of the equipment. In addition, the stator 331 is cooled by coupling the cooling pipe 510 with the heat sink, which improves the cooling efficiency, reduces the noise during cooling, provides a better working environment for the staff, and can significantly reduce the cooling cost of the stator 331.

[0072] (3) The output power of the drive unit 300 can be self-regulated according to the size of the fluid flow rate. When the fluid flow rate is small, the output power of the drive unit 300 is reduced to avoid energy waste. When the fluid flow rate is large, the output power of the drive unit 300 is increased, so that the centrifugal pump can meet the fluid transportation requirements. In addition, the coil will release a large amount of heat during operation. When the temperature of the stator 331 is too high, the current passing through the coil is adjusted to zero, the magnetic field strength generated by the coil is zero, the speed of the rotor 321 is zero, and the drive unit 300 stops automatically to avoid excessive heat from damaging the coil winding 330.

[0073] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A centrifugal pump with an axially integrated motor drive, characterized in that Comprising: A volute having a cavity, with a suction inlet and a discharge outlet formed on the volute and communicating with the cavity. The volute includes a housing body and an end cover. The cavity is formed within the housing body, and both axial ends of the cavity are open. The end cover is detachably fixed to one end of the cavity to seal the opening at one end of the cavity; An impeller rotatably disposed within the cavity; A drive unit including a main shaft, a permanent magnet group, and a coil winding. The main shaft is rotatably disposed within the cavity along the axial direction of the volute and is coaxially fixed to the impeller. The permanent magnet group is disposed within the cavity and is located between the end cover and the impeller. It includes a rotor and a plurality of permanent magnets. The rotor is coaxially fixed to the main shaft. A plurality of receiving grooves are formed on the side wall of the rotor facing the end cover, and each of the permanent magnets is detachably disposed within a corresponding receiving groove. The coil winding is fixed to the volute and corresponds to the permanent magnet group. The coil winding includes a stator and a coil, and the coil is wound around the stator. The coil is electrically connected to a power source; A filtering unit including a first filter element disposed within the cavity and located between the impeller and the permanent magnet group. The first filter element includes a housing and a plurality of discs. The housing is in a funnel-shaped structure and has a filtering cavity in a funnel-shaped structure. Both axial ends of the filtering cavity are open. The outer side wall of the housing is fixed to the inner side wall of the cavity. Each of the discs is in an annular structure and is rotatably and sealingly disposed at intervals along the axial direction of the filtering cavity within the filtering cavity. Each of the discs is also fixedly sleeved on the main shaft, and a plurality of filtering holes are formed on each of the discs; A cooling unit for cooling the coil winding. The cooling unit includes a cooling pipe and a plurality of heat dissipation fins. The cooling pipe is in a serpentine structure and is wound around the outer side wall of the stator in a spiral manner. One end of the cooling pipe is close to the suction inlet to form an inlet, and the other end of the cooling pipe is far from the suction inlet to form an outlet. Each of the heat dissipation fins is disposed within the gap between adjacent cooling pipes and is fixed to the outer side wall of the stator; A control unit is used to monitor the pressure in the cavity and the temperature of the coil winding, and adjust the magnitude of the current passing through the coil winding. The control unit includes a data acquisition mechanism, a data processing mechanism, and an adjustment mechanism. The data acquisition mechanism includes a pressure sensor and a temperature sensor. The pressure sensor is disposed in the cavity to collect the pressure in the cavity, judge the fluid flow rate according to the magnitude of the pressure, and convert the pressure signal into an electrical signal. The temperature sensor is disposed on the outer side wall of the stator to collect the temperature on the outer surface of the stator and convert the temperature signal into an electrical signal. The data processing mechanism is a central processing unit, which is used to receive and process the electrical signals of the pressure sensor and the temperature sensor and issue instructions. When the pressure in the cavity is small, it indicates that the fluid flow rate in the cavity is small, and the magnitude of the current passing through the coil is reduced, the magnetic field intensity generated by the coil is weakened, and the rotational speed of the rotor is reduced. When the pressure in the cavity is large, it indicates that the fluid flow rate in the cavity is large, and the magnitude of the current passing through the coil is increased, the magnetic field intensity generated by the coil is enhanced, and the rotational speed of the rotor is increased. When the temperature of the stator reaches the preset temperature, the magnitude of the current passing through the coil is zero, the magnetic field intensity generated by the coil is zero, and the rotational speed of the rotor is zero. The adjustment mechanism includes a current sensor and a rotational speed sensor. The current sensor is disposed in the circuit where the coil is connected to the power supply, and the rotational speed sensor is disposed on the rotor. Both the current sensor and the rotational speed sensor are used to receive the instructions issued by the central processing unit, and adjust the magnitude of the current through the current sensor and adjust the rotational speed of the rotor through the rotational speed sensor.

2. The centrifugal pump with an axially integrated motor drive according to claim 1, characterized in that, The volute also includes a suction pipe, a discharge pipe, and two flanges. The suction pipe is axially disposed at the other end of the housing along the cavity, one end of the suction pipe is communicated with the opening at the other end of the cavity, and the other end of the suction pipe forms the suction port. The discharge pipe is tangentially disposed at the side of the housing along the cavity, one end of the discharge pipe is communicated with the cavity, and the other end of the discharge pipe forms the discharge port. The two flanges are respectively fixedly sleeved on the other ends of the corresponding suction pipe and discharge pipe.

3. The centrifugal pump with an axially integrated motor drive according to claim 2, characterized in that, The rotor is of a disc structure and is detachably and fixedly sleeved on the main shaft.

4. The centrifugal pump with axially integrated motor drive according to claim 3, characterized in that, The stator has a receiving cavity with one side open, the opening side of the receiving cavity faces the end cover, the stator is detachably and fixedly connected to the end cover, and the coil is disposed in the receiving cavity.

5. The centrifugal pump with an axially integrated motor drive according to claim 1, characterized in that, The filtering unit further includes a second filtering member, and the second filtering member is disposed at the suction port for filtering impurities entering the suction port.

6. The centrifugal pump with an axially integrated motor drive according to claim 1, characterized in that, The distance between adjacent pipe segments of the cooling pipe in the middle of the stator is smaller than the distance between adjacent pipe segments of the cooling pipe at both ends of the stator, and the pipe diameter at the inlet of the cooling pipe and the pipe diameter at the outlet of the cooling pipe are both larger than the pipe diameter at the middle section of the cooling pipe.

7. The centrifugal pump with an axially integrated motor drive according to claim 1, characterized in that, The control unit further includes a data display mechanism, and the data display mechanism is a display screen for displaying pressure and temperature information.

8. A control method for an axially integrated motor-driven centrifugal pump, applicable to the axially integrated motor-driven centrifugal pump described in any one of claims 1 - 7, characterized in that, The steps are as follows: The control unit monitors the pressure in the cavity and the temperature of the coil winding. When the pressure in the cavity is small, it indicates that the fluid flow rate in the cavity is small. The control unit reduces the magnitude of the current passing through the coil winding, the magnetic field strength generated by the coil winding weakens, and the rotational speed of the permanent magnet group decreases. When the pressure in the cavity is large, it indicates that the fluid flow rate in the cavity is large. The control unit increases the magnitude of the current passing through the coil winding, the magnetic field strength generated by the coil winding increases, and the rotational speed of the permanent magnet group increases. When the temperature of the coil winding reaches the preset temperature, the control unit adjusts the magnitude of the current passing through the coil winding to zero, the magnetic field strength generated by the coil winding is zero, and the rotational speed of the permanent magnet group is zero.

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