Self-adaptive variable-frequency shield pump

Abstract

The self-adaptive variable-frequency shield pump comprises a shell, a control box located at the rear end of the shell and a control system arranged in the control box, the shell is installed at the front end of a pump head, an input pipe and an output pipe are symmetrically arranged on the two sides of the pump head, a shielding sleeve is arranged in the shell in a sleeved mode, an impeller is arranged on the outer side of the shielding sleeve, and the control system is arranged in the control box. A cover plate is installed on the rear side of the impeller, a stator coil is installed in the shell, and a rotor is arranged in the shielding sleeve. The operation frequency of the pump is adaptively adjusted in real time, so that the pump always runs close to the optimal working condition point, the overall operation efficiency of the pump can be remarkably improved, the energy consumption is reduced, meanwhile, the service life can be prolonged, potential risks such as cavitation and overload can be sensed in time, prevention measures can be taken in advance, and the safety is improved. The pump body can accurately cope with complex working conditions such as pipeline resistance change and medium property fluctuation, stable operation of a fluid conveying system is ensured, and the risk of production interruption caused by unstable operation of the pump is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of canned pumps, in particular to an adaptive variable frequency canned pump. Background Art

[0002] The core of the canned motor pump is the canned motor. The stator and rotor of the motor are sealed in a thin-walled cylinder called a shielding sleeve. The shielding sleeve is generally made of non-magnetic stainless steel and other materials, and is very thin, usually around 0.3-1mm. This design is to prevent the medium being transported from directly contacting the motor windings, while ensuring that the magnetic field generated by the motor can effectively act on the rotor to drive the pump shaft to rotate. The canned pump has the advantages of no leakage and smooth operation. It is widely used in many fields such as chemical, petroleum, pharmaceutical, refrigeration, etc. It is particularly important for conveying special media or occasions requiring high sealing.

[0003] However, traditional canned motor pumps usually operate at a fixed frequency, and cannot flexibly adjust their operating status when actual working conditions change, such as changes in the flow demand, changes in pipeline resistance, or fluctuations in the physical properties of the transported medium. This may lead to reduced pump efficiency, increased energy consumption, and even cavitation, overload and other problems in extreme cases, affecting the service life of the pump and the stability of the system. Summary of the invention

[0004] In order to make up for the deficiencies of the prior art and solve the problems encountered, the present invention proposes an adaptive variable frequency canned pump.

[0005] An adaptive variable frequency shielded pump comprises a shell, a control box located at the rear end of the shell, and a control system arranged inside the control box. The shell is installed at the front end of a pump head, and an input pipe and an output pipe are symmetrically arranged on both sides of the pump head. A shielding sleeve is arranged inside the shell, an impeller is arranged on the outside of the shielding sleeve, a cover plate is installed on the rear side of the impeller, a stator coil is installed inside the shell, a rotor is arranged inside the shielding sleeve, an axial hole is opened at the top end of the rotor, a bearing is installed at the rear end of the rotor, and a through hole is opened at the rear end of the rotor.

[0006] Preferably, the control system includes a controller, a frequency converter and a data processor, the controller is used to receive a plurality of sensor signals, perform calculations and processing, and issue control instructions, and the frequency converter adjusts the power supply frequency of the motor according to the controller instructions;

[0007] Multiple sensors are located at key locations on the pump and piping system, including: flow sensors, installed near the pump’s output pipe, to monitor the pump’s actual delivery flow in real time;

[0008] Pressure sensors are placed in the input pipe and output pipe of the pump to measure the inlet and outlet pressures;

[0009] The temperature sensor is arranged on the outside of the shell and at the location where the conveyed medium flows through, and is used to monitor the temperature changes of the pump body, motor and medium.

[0010] Preferably, the impeller is installed at the front end of the rotor, the shielding sleeve is arranged inside the stator coil, and the impeller is arranged inside the pump head.

[0011] Preferably, the shaft hole is connected to a through hole, and the through hole is arranged on one side of the bearing.

[0012] Preferably, the data processor of the control system pre-processes the raw data transmitted by multiple sensors, extracts effective feature information, and compares the processed data with a preset operating condition model. If a deviation is found between the current operating condition and the ideal operating condition, the controller calculates the required frequency adjustment amount according to the built-in algorithm and accurately adjusts the motor power supply frequency through the frequency converter.

[0013] The present invention is beneficial in that:

[0014] The present invention adaptively adjusts the operating frequency of the pump in real time so that it always operates close to the optimal operating point, which can significantly improve the overall operating efficiency of the pump, reduce energy consumption, and extend its service life. It can timely sense potential risks such as cavitation and overload, and take preventive measures in advance, so that the pump body can accurately respond to complex operating conditions such as changes in pipeline resistance and fluctuations in medium properties, thereby ensuring the stable operation of the fluid delivery system and reducing the risk of production interruption due to unstable operation of the pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0016] Figure 1 It is a schematic diagram of the overall structure of the adaptive variable frequency canned pump of the present invention.

[0017] Figure 2 Schematic diagram of the internal structure of the adaptive variable frequency canned pump of the present invention

[0018] Figure 3 Schematic diagram of the shielding sleeve structure of the adaptive variable frequency shielded pump of the present invention

[0019] Figure 4 The schematic diagram of the rotor structure of the adaptive variable frequency canned motor pump of the present invention is

[0020] Figure 5The schematic diagram of the rotor rear structure of the adaptive variable frequency canned motor pump of the present invention is

[0021] Figure 6 It is a schematic diagram of the adaptive variable frequency canned pump control system of the present invention.

[0022] In the figure: 1. casing; 2. control box; 3. pump head; 4. inlet pipe; 5. outlet pipe; 6. shielding sleeve; 7. impeller; 8. cover plate; 9. stator coil; 10. rotor; 11. shaft hole; 12. bearing; 13. through hole. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] See also Figure 1-6 As shown, the adaptive variable frequency canned pump includes a shell 1, a control box 2 located at the rear end of the shell 1, and a control system arranged inside the control box 2. The shell 1 is installed at the front end of the pump head 3. The pump head 3 is symmetrically provided with an input pipe 4 and an output pipe 5 on both sides. A shielding sleeve 6 is provided inside the shell 1, and an impeller 7 is provided outside the shielding sleeve 6. The impeller 7 is arranged inside the pump head 3. A cover plate 8 is installed on the rear side of the impeller 7. A stator coil 9 is installed inside the shell 1, and the shielding sleeve 6 is arranged inside the stator coil 9. A rotor 10 is arranged inside the shielding sleeve 6. The impeller 7 is installed at the front end of the rotor 10. An axial hole 11 is opened at the top of the rotor 10. A bearing 12 is installed at the rear end of the rotor 10. The bearing 12 makes the rotor 10 rotate more smoothly. A through hole 13 is opened at the rear end of the rotor 10. The axial hole 11 is connected with the through hole 13, and the through hole 13 is arranged on one side of the bearing 12.

[0025] When the pump body is used, the input pipe 4 and the output pipe 5 on both sides of the pump head 3 are installed on the delivery pipeline, and then a rotating magnetic field is generated through the stator coil 9. The magnetic field acts on the rotor 10 through the shielding sleeve 6, so that the rotor 10 inside the shielding sleeve 6 drives the front impeller 7 to rotate. When the impeller 7 rotates, the liquid at the center of the impeller 7 is thrown to the edge of the impeller 7 due to the centrifugal force, so that a low-pressure area is formed in the center of the impeller 7, and the liquid in the input pipe 4 of the pump is pressed into the center of the impeller under the action of external pressure. The liquid entering the impeller obtains kinetic energy and pressure energy under the high-speed rotation of the impeller 7, and then the liquid flows out from the edge of the impeller 7 and enters the pump head 3. In the pump head 3, the kinetic energy of the liquid is further converted into pressure energy, and finally discharged from the output pipe 5 of the pump to realize the delivery of the liquid; and when the rotor 10 rotates, part of the liquid will enter the shaft hole 11, and then flow out from the through hole 13, so that the liquid is injected into the shielding sleeve 6, and the heat generated by the operation of the stator coil 9 can be taken away by the flow of the liquid inside the shielding sleeve 6, so as to better control the temperature.

[0026] The control system includes a controller, a frequency converter and a data processor. The controller is used to receive multiple sensor signals, perform calculations and processing, and issue control instructions. The frequency converter adjusts the power supply frequency of the motor according to the controller instructions.

[0027] Multiple sensors are distributed at key locations of the pump body and the piping system, including: a flow sensor, installed near the output pipe 5 of the pump, for real-time monitoring of the actual delivery flow of the pump;

[0028] Pressure sensors are placed on the pump input pipe 4 and output pipe 5 respectively to measure the inlet and outlet pressures;

[0029] The temperature sensor is arranged on the outside of the housing 1 and at the part where the conveyed medium flows through, and is used to monitor the temperature changes of the pump body, the motor and the medium. The data processor of the control system pre-processes the raw data transmitted by multiple sensors, extracts effective characteristic information, and compares the processed data with the preset working condition model. If it is found that the current working condition deviates from the ideal working condition, the controller calculates the required frequency adjustment amount according to the built-in algorithm, and accurately adjusts the motor power supply frequency through the inverter;

[0030] When the pump is running, the flow sensor, pressure sensor and temperature sensor start to collect data synchronously. The flow sensor uses a high-precision electromagnetic flowmeter to send real-time flow data to the control system at regular intervals; the pressure sensor uses a piezoresistive pressure sensor, which can accurately measure tiny pressure changes and provide real-time feedback; the temperature sensor uses the principle of thermistor to quickly sense temperature fluctuations and also transmit data in real time.

[0031] The data processor of the control system processes the received data quickly. When the flow sensor detects that the current delivery flow rate is lower than the preset lower limit, the data processor transmits the information to the controller. Based on the built-in algorithm, the controller combines the current pressure, temperature and other factors to calculate the specific value of the stator coil 9 and the rotor 10 operating frequency, and then sends a command to the frequency converter. The frequency converter quickly adjusts the power supply frequency, so that the speed of the rotor 10 increases accordingly, and the delivery flow rate gradually returns to the ideal range.

[0032] If the pressure sensor detects that the pressure in the input pipe 5 is too low, it indicates that there may be problems such as suction pipe blockage or insufficient air source. The control system will also start the emergency adjustment program. On the one hand, it will reduce the operating frequency of the pump to prevent cavitation. On the other hand, it will issue a warning to the operator through an external alarm device to prompt him to check the cause of the fault.

[0033] During the operation of the stator coil 9 and the rotor 10, the temperature sensor closely monitors the temperature of the housing 1. Once the temperature exceeds the set threshold, the control system immediately takes cooling measures, such as appropriately reducing the operating frequency of the stator coil 9 and the rotor 10, and increasing the cooling water flow rate to ensure that the motor operates within a safe temperature range.

[0034] As the pump runs for a long time, the control system continuously accumulates data on operating condition changes and corresponding adjustment experience. During transportation, the concentration of the medium will change periodically with the reaction process, causing the pipeline resistance and the required transportation flow rate to change accordingly. After many such operating cycles, the control system gradually grasps this law. The next time a similar situation occurs, it can predict in advance and adjust the pump's operating frequency more accurately and quickly, achieving truly adaptive operation.

[0035] Working principle: When the pump body is used, the input pipe 4 and the output pipe 5 on both sides of the pump head 3 are installed on the delivery pipeline, and then a rotating magnetic field is generated through the stator coil 9. The magnetic field acts on the rotor 10 through the shielding sleeve 6, so that the rotor 10 inside the shielding sleeve 6 drives the front impeller 7 to rotate. When the impeller 7 rotates, the liquid at the center of the impeller 7 is thrown to the edge of the impeller 7 due to the centrifugal force, so that a low-pressure area is formed in the center of the impeller 7, and the liquid in the input pipe 4 of the pump is pressed into the center of the impeller under the action of external pressure. The liquid entering the impeller obtains kinetic energy and pressure energy under the high-speed rotation of the impeller 7, and then the liquid flows out from the edge of the impeller 7 and enters the pump head 3. In the pump head 3, the kinetic energy of the liquid is further converted into pressure energy, and finally discharged from the output pipe 5 of the pump to realize the delivery of the liquid; at the same time, when the pump body is running, the flow sensor, pressure sensor and temperature sensor start to collect data synchronously. The flow sensor uses a high-precision electromagnetic flowmeter to send real-time flow data to the control system at a regular time; when the flow sensor detects that the current delivery flow is lower than the preset lower limit, the data processor transmits the information to the controller. Based on the built-in algorithm, the controller combines the current pressure, temperature and other factors to calculate the specific values ​​of the stator coil 9 and the rotor 10 operating frequency, and then sends a command to the frequency converter. The frequency converter quickly adjusts the power supply frequency, so that the speed of the rotor 10 increases accordingly, and the delivery flow gradually returns to the ideal range; if the pressure sensor detects that the pressure of the input pipe 5 is too low, it indicates that there may be problems such as suction pipe blockage or insufficient air source. The control system will also start the emergency adjustment program. On the one hand, it reduces the operating frequency of the pump to prevent cavitation; on the other hand, it issues a warning to the operator through an external alarm device, prompting the operator to check the cause of the fault.

[0036] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0037] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. Adaptive variable frequency canned motor pump, characterized in that: The invention comprises a housing (1), a control box (2) located at the rear end of the housing (1), and a control system arranged inside the control box (2); the housing (1) is mounted at the front end of a pump head (3); an inlet pipe (4) and an outlet pipe (5) are symmetrically arranged on both sides of the pump head (3); a shielding sleeve (6) is sleeved inside the housing (1); an impeller (7) is arranged outside the shielding sleeve (6); a cover plate (8) is installed at the rear side of the impeller (7); a stator coil (9) is installed inside the housing (1); a rotor (10) is arranged inside the shielding sleeve (6); a shaft hole (11) is opened at the top end of the rotor (10); a bearing (12) is installed at the rear end of the rotor (10); and a through hole (13) is opened at the rear end of the rotor (10).

2. The adaptive variable frequency canned motor pump according to claim 1, characterized in that: The control system includes a controller, a frequency converter and a data processor, wherein the controller is used to receive a plurality of sensor signals, perform calculations and processing, and issue control instructions, and the frequency converter adjusts the power supply frequency of the motor according to the instructions of the controller; Multiple sensors are distributed at key locations of the pump body and the piping system, including: a flow sensor installed near the pump output pipe (5) for real-time monitoring of the actual delivery flow of the pump; Pressure sensors are respectively placed on the inlet pipe (4) and the outlet pipe (5) of the pump and are used to measure the inlet and outlet pressures; The temperature sensor is arranged on the outside of the housing (1) and at a location where the conveyed medium flows, and is used to monitor temperature changes of the pump body, the motor and the medium.

3. The adaptive variable frequency canned motor pump according to claim 1, characterized in that: The impeller (7) is mounted on the front end of the rotor (10), the shielding sleeve (6) is arranged inside the stator coil (9), and the impeller (7) is arranged inside the pump head (3).

4. The adaptive variable frequency canned motor pump according to claim 3, characterized in that: The shaft hole (11) is connected to the through hole (13), and the through hole (13) is arranged on one side of the bearing (12).

5. The adaptive variable frequency canned motor pump according to claim 2, characterized in that: The data processor of the control system pre-processes the raw data transmitted by multiple sensors, extracts effective feature information, and compares the processed data with the preset operating condition model. If it is found that the current operating condition deviates from the ideal operating condition, the controller calculates the required frequency adjustment amount according to the built-in algorithm and accurately adjusts the motor power supply frequency through the inverter.

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