Split electromagnetic clutch maintenance-free centrifugal pump and jet self-suction device

Abstract

The utility model relates to centrifugal pump technical field provides a kind of split type electromagnetic clutch maintenance-free centrifugal pump, including pump body, and pump body is equipped with shutdown sealing element, and shutdown sealing element includes rotating ring, non-rotating ring, sucking disc, split seat and magnetic supply structure, split seat includes fixed end and movable end, sucking disc is fixed on non-rotating ring by movable end, and magnetic supply structure attracts sucking disc, and the sealing surface of non-rotating ring moves to separate with the sealing surface of rotating ring, and when magnetic supply structure does not attract sucking disc, the sealing surface of non-rotating ring resets to be attached with the sealing surface of rotating ring. Still provide a kind of injection self-suction device. When the utility model stops, by the cooperation of magnetic supply structure and sucking disc, the movement of non-rotating ring can be more stable, realized the "non-contact type" operation of sealing state switching, reduced the difficulty of installation maintenance, wear risk, the problem that sealing surface wear, mechanical energy loss cannot occur between the two, without setting sealing ring.

Description

Technical Field

[0001] This utility model relates to the field of centrifugal pump technology, specifically a split-type electromagnetic clutch maintenance-free centrifugal pump and a jet self-priming device. Background Technology

[0002] Centrifugal pumps are commonly used in chemical, metallurgical, and environmental protection industries to transport fluid media. However, frequent shaft seal burnout, high maintenance rates due to leakage, low pump efficiency, significant mechanical energy loss, and high energy consumption due to the use of mechanical seal isolation fluid have long plagued industry professionals. Especially when the medium is prone to crystallization, contains solid particles, or operates at high temperatures (>150℃), shaft seal damage is easily caused, leading to substantial leakage of process media and impacting process system stability, safety, and environmental protection. Specifically: When a dynamic shaft seal is used, a negative pressure zone is created by the rotation of an auxiliary impeller within the impeller chamber, preventing the medium from leaking along the pump shaft past the impeller chamber and impeller. While this provides effective sealing during pump operation, significant leakage occurs when the pump stops. When a combination of dynamic and shutdown seals is used, shutdown seals, typically employing packing, coil, or spring seals, often exhibit poor sealing performance. This is particularly problematic when the process medium is prone to crystallization and scaling, easily leading to shutdown seal failure and necessitating the addition of a mechanical seal isolation fluid. Utility Model Content

[0003] The purpose of this invention is to provide a split-type electromagnetic clutch maintenance-free centrifugal pump and a self-priming jet device, which can at least solve some of the defects in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a split-type electromagnetic clutch maintenance-free centrifugal pump, comprising a pump body, a stop seal provided outside the pump body, the stop seal comprising a rotating ring, a non-rotating ring, a suction cup, a split seat, and a magnetic supply structure, the split seat comprising a fixed end and a movable end, the suction cup being fixed to the non-rotating ring via the movable end, the magnetic supply structure attracting the suction cup, the sealing surface of the non-rotating ring moving with the suction cup to separate from the sealing surface of the rotating ring, and when the magnetic supply structure no longer attracts the suction cup, the sealing surface of the non-rotating ring resetting to fit against the sealing surface of the rotating ring.

[0005] Furthermore, it also includes a pump shaft and a bearing cover, with both the rotating ring and the non-rotating ring fitted onto the pump shaft, and the magnetizing structure fixed onto the bearing cover.

[0006] Furthermore, the split seat also includes a spring for resetting the non-rotating ring, the spring being disposed on the pump shaft and located between the non-rotating ring and the bearing cap.

[0007] Furthermore, one end face of the pump body is provided with an inlet and an outlet, and the other end face of the pump body is provided with a pump cover, through which the pump shaft enters the pump body.

[0008] Furthermore, the fixed end is fixed to the pump cover.

[0009] Furthermore, it also includes a dynamic seal for shaft sealing, the dynamic seal comprising an impeller, an auxiliary impeller chamber mounted on the pump body, and an auxiliary impeller located within the auxiliary impeller chamber, both the impeller and the auxiliary impeller being connected to the pump shaft, the auxiliary impeller chamber being located on the side of the impeller away from the inlet of the pump body.

[0010] Furthermore, the impeller has auxiliary blades on the side near the auxiliary impeller chamber.

[0011] Furthermore, the magnetizing structure includes an electromagnetic coil connected to an external circuit. The external circuit supplies power to the electromagnetic coil, which generates magnetism to attract the chuck. When the external circuit is de-energized, the electromagnetic coil loses its magnetism and loses its attraction to the chuck, causing the chuck to reset and thus resetting the non-rotating ring.

[0012] Furthermore, it also includes a time relay electrically connected to the external circuit.

[0013] This utility model embodiment provides another technical solution: a self-priming jet device, including the above-mentioned split-type electromagnetic clutch maintenance-free centrifugal pump.

[0014] Compared with the prior art, the beneficial effects of this utility model are: when the machine is stopped, the movement of the non-rotating ring can be achieved more stably through the cooperation of the magnetic supply structure and the suction cup, realizing the "non-contact" operation of the sealing state switching, reducing the difficulty of installation and maintenance and the risk of wear. There will be no problem of sealing surface wear or mechanical energy loss between the two. There is no need to set a sealing ring, which solves the problem of sealing ring deterioration and failure under high temperature (>150℃). There is no need for mechanical seal isolation fluid, which reduces frictional resistance. It has good tracking and shock resistance, and has a large tolerance for pump shaft vibration and deviation. Attached Figure Description

[0015] Figure 1 A vertical cross-sectional structural diagram of a self-priming spray device provided in Embodiment 1 of this utility model;

[0016] Figure 2 for Figure 1 A schematic diagram of the vertical cross-sectional structure of the nozzle and the jet pump body;

[0017] Figure 3 This is a vertical cross-sectional view of a suction cup type maintenance-free centrifugal pump provided in Embodiment 2 of this utility model;

[0018] Figure 4 A vertical cross-sectional view of a suction cup-type maintenance-free centrifugal pump shutting down, as provided in Embodiment 2 of this utility model;

[0019] Figure 5 This is a vertical cross-sectional structural diagram of a suction cup type maintenance-free centrifugal pump in operation according to Embodiment 2 of this utility model;

[0020] Figure 6 A vertical cross-sectional view of a maintenance-free centrifugal pump with an integrated permanent magnet seal, provided in Embodiment 3 of this utility model;

[0021] Figure 7 A vertical cross-sectional view of the shutdown structure of a maintenance-free centrifugal pump with an integrated permanent magnet seal, provided in Embodiment 3 of this utility model;

[0022] Figure 8 A vertical cross-sectional structural diagram of an integrated permanent magnet seal maintenance-free centrifugal pump provided in Embodiment 3 of this utility model;

[0023] Figure 9 A vertical cross-sectional view of a maintenance-free centrifugal pump with a permanent magnet seal provided in Embodiment 4 of this utility model;

[0024] Figure 10 A vertical cross-sectional view of a maintenance-free centrifugal pump with a permanent magnet seal during shutdown, as provided in Embodiment 4 of this utility model;

[0025] Figure 11 A vertical cross-sectional structural diagram of a maintenance-free centrifugal pump with a permanent magnet seal provided in Embodiment 4 of this utility model;

[0026] Figure 12 A vertical cross-sectional structural diagram of a split-type electromagnetic clutch maintenance-free centrifugal pump provided in Embodiment 5 of this utility model;

[0027] Figure 13 A vertical cross-sectional structural diagram of a split-type electromagnetic clutch maintenance-free centrifugal pump for stopping, provided in Embodiment 5 of this utility model;

[0028] Figure 14 This is a vertical cross-sectional structural diagram of a split-type electromagnetic clutch maintenance-free centrifugal pump provided in Embodiment 5 of this utility model. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0030] Example 1:

[0031] Please see Figure 1 and Figure 2 This utility model provides a self-priming jet device, including a maintenance-free centrifugal pump, a nozzle, and a jet pump body. The nozzle is disposed on the jet pump body, and the jet pump body is connected to the outlet of the maintenance-free centrifugal pump. The maintenance-free centrifugal pump includes a shutdown seal for shaft sealing during shutdown. In this embodiment, the nozzle, jet pump body, and shutdown seal work together to achieve a partial vacuum self-priming effect, ensuring safe and efficient operation, reducing installation and maintenance difficulty and wear risk. There is no wear on the sealing surface or loss of mechanical energy between them. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It has good tracking and vibration resistance, and a large tolerance for pump shaft vibration and misalignment. Specifically, this self-priming jet device is as follows... Figure 1 and Figure 2 As shown, a maintenance-free centrifugal pump is incorporated. The centrifugal pump includes a pump body 1, with an inlet at the front end, an outlet on the side, and a pump cover 6 at the rear end. An externally driven pump shaft 4 passes through the pump cover 6 and enters the pump body 1. An impeller 2 with a guide channel is installed at the front end of the pump shaft 4. A straight pipe section 15 is provided at the outlet end of the pump body 1. The self-priming jet device also includes a nozzle 17 and a jet pump body 16. During operation, high-pressure gas forms a high-speed jet through the nozzle 17, which is pressurized by the mixing chamber and diffuser section within the jet pump body 16 before being discharged, creating a partial vacuum. This vacuum generates suction force on the air and liquid in the suction pipe, achieving a self-priming effect. The pump body 1 has a power seal and a shutdown seal on its inner and outer sides, respectively. The power seal includes an auxiliary blade on the back of the impeller 2, an auxiliary impeller chamber 3 located behind the impeller 2 and mounted on the pump body 1, and an auxiliary impeller 5 located within the auxiliary impeller chamber 3 and connected to the pump shaft 4. As for the shutdown seal, four structural forms can be adopted, namely the shutdown seals refined in Embodiments 2, 3, 4, and 5. The embodiments below will be described in detail. Figure 1The image shown is only the shutdown seal shown in Embodiment 2. Furthermore, a dynamic seal is also present in every embodiment, and their structures are identical. By employing both dynamic and shutdown seals, sealing is achieved during both operation and shutdown, eliminating the need for mechanical seal isolation fluid, extending service life, reducing the need for frequent priming, and preventing wear during operation. It can operate reliably even at high temperatures, in media containing sludge particles, and when the level of the transported liquid is lower than the pump inlet height. It is particularly suitable for centrifugal pump applications with frequent start-stop cycles or self-priming requirements.

[0032] Please see Figure 1 and Figure 2 This centrifugal pump requires no frequent priming, has strong cavitation resistance, low mechanical energy loss, does not require mechanical seal isolation fluid, and is highly durable for media prone to crystallization / scaling. The jet self-priming device achieves efficient and reliable self-priming: high-pressure gas forms a high-speed jet through the nozzle, creating a low-pressure zone at the nozzle outlet, forming a partial vacuum, which generates suction force on the air and liquid in the suction pipe, achieving self-priming. When the liquid level in the pump body 1 rises to the level sensor in the straight pipe section 15, which monitors the self-priming status in real time, the PLC switches to centrifugal pump mode and starts the sealing standby when it detects pure liquid flow. The dynamic seal ensures sealing during operation: during operation, the auxiliary blades reduce the back pressure of the impeller 2, keeping the pump axial force in a balanced state. Simultaneously, the auxiliary impeller 5 rotates within the auxiliary impeller chamber 3, creating a negative pressure zone, preventing the medium inside the pump from leaking along the pump shaft 4 past the auxiliary impeller chamber 3 and the auxiliary impeller 5, and also avoiding damage to the rear components of the auxiliary impeller 5 from corrosive, high-temperature, and solid particle-containing media. Finally, a shutdown seal ensures sealing during shutdown. It achieves reliable self-priming, and the coordinated operation of the jet self-priming device and the dual sealing system ensures safe and efficient operation, reduces installation and maintenance difficulty and wear risk. There is no wear on the sealing surface or loss of mechanical energy between the two systems, eliminating the need for sealing rings and solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). It also eliminates the need for mechanical seal isolation fluid, reducing frictional resistance, and provides excellent tracking and vibration resistance, with a high tolerance for pump shaft vibration and misalignment. This centrifugal pump exhibits high durability for hazardous media such as those prone to crystallization, scaling, those that are stable at room temperature, flammable, and explosive. It is well-suited for applications where the liquid level is lower than the inlet height and can be widely used in chemical, metallurgical, and environmental fluid transport fields. Figure 1 and Figure 2 As shown, during operation, high-pressure gas forms a high-speed jet through nozzle 17, creating a low-pressure zone at the nozzle 17 outlet, forming a partial vacuum. This vacuum generates a suction force on the air and liquid in the suction pipe, achieving a self-priming effect. When the liquid level in the pump body 1 rises to a level monitored in real time by the liquid level sensor in the straight pipe section 15, the PLC switches to centrifugal pump mode and activates the centrifugal pump's sealing mechanism for standby when it detects pure liquid flow. The centrifugal pump's seals include the dynamic seal and the shutdown seal described in the above embodiment.

[0033] Please see Figure 1 The liquid level sensor on the outlet straight pipe section 15 monitors the liquid level in real time. Upon detecting liquid, the self-priming jet device immediately stops operating and simultaneously switches the centrifugal pump to the operating mode. During operation, high-pressure gas forms a high-speed jet through the nozzle, creating a low-pressure zone at the nozzle outlet and forming a partial vacuum. This vacuum generates a suction force on the air and liquid in the suction pipe, achieving a self-priming effect. The rear end of the pump shaft 4 is connected to an external drive after passing through the bearing 14.

[0034] Example 2:

[0035] Please see Figures 3 to 5 This utility model provides a suction cup type maintenance-free centrifugal pump, including a pump body. A shutdown seal is provided outside the pump body. The shutdown seal includes a rotating ring, a non-rotating ring, a suction cup, and a magnetic supply structure. The suction cup is fixed to the non-rotating ring. The magnetic supply structure attracts the suction cup, and the sealing surface of the non-rotating ring moves with the suction cup to separate from the sealing surface of the rotating ring. When the magnetic supply structure no longer attracts the suction cup, the sealing surface of the non-rotating ring returns to its original position to fit against the sealing surface of the rotating ring. In this embodiment, during shutdown, the cooperation between the magnetic supply structure and the suction cup allows for more stable movement of the non-rotating ring, achieving a "non-contact" operation for switching the sealing state. This reduces the difficulty of installation and maintenance, and the risk of wear. There is no wear on the sealing surface or loss of mechanical energy between the two components. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It has good tracking and vibration resistance, and a large tolerance for pump shaft vibration and misalignment. This suction cup-type maintenance-free centrifugal pump can be used in the self-priming jet device of one of the above embodiments. The function of the magnetic supply structure is to provide magnetic attraction to the suction cup, thereby driving the non-rotating ring. There are many ways to supply magnets to the magnetic supply structure; for example, the electromagnetic coil in this embodiment can be used, or the permanent magnet schemes of embodiments two and three can be used. Preferably, the magnetic supply structure includes an electromagnetic coil connected to an external circuit. The external circuit supplies power to the electromagnetic coil, and the electromagnetic coil generates magnetism to attract the suction cup. When the external circuit is de-energized, the electromagnetic coil loses its magnetism and its attraction to the suction cup, causing the suction cup to reset and driving the non-rotating ring to reset. This centrifugal pump also includes a time relay electrically connected to the external circuit.

[0036] Please see Figures 3 to 5The centrifugal pump further includes a pump shaft and a bearing cover. Both the rotating ring and the non-rotating ring are fitted onto the pump shaft, and the magnetizing structure is fixed to the bearing cover. Preferably, the centrifugal pump further includes a reset structure for resetting the non-rotating ring. The reset structure is located on the pump shaft and between the non-rotating ring and the bearing cover. The reset structure includes a spring that abuts against the suction cup. Preferably, the centrifugal pump further includes a dynamic seal for shaft sealing. The dynamic seal includes an impeller, a secondary impeller chamber mounted on the pump body, and a secondary impeller located within the secondary impeller chamber. Both the impeller and the secondary impeller are connected to the pump shaft. The secondary impeller chamber is located on the side of the impeller away from the inlet of the pump body. The impeller has secondary blades on the side closest to the secondary impeller chamber. A portion of the pump body's end face has an inlet and an outlet, and the other end face of the pump body has a pump cover. The pump shaft passes through the pump cover and enters the pump body. In this embodiment, the suction cup type maintenance-free centrifugal pump includes a pump body 1. The pump body 1 has an inlet at the front end, an outlet on the side, and a pump cover 6 installed at the rear end. An externally driven pump shaft 4 passes through the pump cover 6 and enters the pump body 1. An impeller 2 with a guide flow channel is installed at the front end of the pump shaft 4. A power seal and a shutdown seal are respectively provided inside and outside the pump body 1. The power seal is located between the impeller 2 and the pump cover 6 and includes an auxiliary impeller 5 located between the impeller 2 and the pump cover 6 and sleeved on the pump shaft 4, and an auxiliary blade chamber 3 sleeved outside the auxiliary impeller 5 and cooperating with the pump cover 6. Specifically, the power seal includes an auxiliary blade provided on the back of the impeller 2, an auxiliary impeller chamber 3 located on the rear side of the impeller 2 and installed on the pump body 1, and an auxiliary impeller 5 located in the auxiliary impeller chamber 3 and connected to the pump shaft 4.

[0037] Please see Figures 3 to 5 The shutdown seal is located on the rear side of the pump cover 6 of the centrifugal pump, including a rotating ring 10 fitted on the pump shaft 4, a non-rotating ring 8 located behind the rotating ring 10, a spring 14, a suction cup 12, and an electromagnetic coil 9. The suction cup 12 is fixed to the non-rotating ring 8, the electromagnetic coil 9 is fixed to the bearing cover 11, and the spring 14 is fitted on the pump shaft 4 and located between the non-rotating ring 8 and the bearing cover 11. During operation, an external circuit generates magnetism to attract the suction cup 12, causing the sealing surface of the non-rotating ring 10 to separate from the sealing surface of the rotating ring 8. When the pump stops, the power is cut off, the coil 9 loses its magnetism, and under the action of the spring 14, it separates from the suction cup 12, and the sealing surfaces of the non-rotating ring 8 and the rotating ring 10 return to a tight state. During operation, there is no problem of sealing surface wear or mechanical energy loss. When the pump stops, a seal is achieved, avoiding wear and corrosion of the pump shaft 4 by the medium. No sealing ring or mechanical seal isolation fluid is required, and it can operate reliably even at high temperatures and in media containing silt particles.

[0038] Please see Figures 3 to 5This centrifugal pump requires no frequent maintenance, has low mechanical energy loss, does not require mechanical seal isolation fluid, and is highly durable for media that are prone to crystallization / scaling. Among them, the dynamic seal achieves sealing during operation: during operation, the auxiliary blades can reduce the back pressure of the impeller 2 to keep the pump axial force in a balanced state. At the same time, the auxiliary impeller 5 rotates in the auxiliary impeller chamber 3 to form a negative pressure zone, so that the medium in the pump will not leak along the pump shaft 4 across the auxiliary impeller chamber 3 and the auxiliary impeller 5. It also avoids damage to the rear components of the auxiliary impeller 5 by corrosive, high-temperature, and solid particle-containing media. Moreover, the electromagnetic coil 9, which generates magnetism when energized, attracts the suction cup 12 to make the two completely fit together, thereby compressing the spring 14 and moving the free end of the non-rotating ring 8 away from the rotating ring 10. There will be no problem of sealing surface wear or mechanical energy loss between the two.

[0039] Please see Figures 3 to 5 The shutdown seal achieves sealing during shutdown: when the pump stops, the electromagnetic coil 9, demagnetized and disconnected from the suction cup 12, separates from the coil 9. Under the pressure of the spring 14, the free end of the non-rotating ring 8 moves towards the rotating ring 10 until it re-adheres to the sealing surface of the rotating ring 10, achieving a seal at the joint. This reduces the difficulty of installation and maintenance, and the risk of wear. There is no wear on the sealing surface or loss of mechanical energy between the two components. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It has good tracking and vibration resistance, and a large tolerance for vibration and misalignment of the pump shaft 4. This centrifugal pump has high durability for hazardous media such as those prone to crystallization, scaling, those that are stationary at room temperature, and those that are flammable or explosive. It can be widely used in the chemical, metallurgical, and environmental fluid transport fields.

[0040] Please see Figures 3 to 5 The shutdown seal is located on the rear side of the pump cover 6 of the centrifugal pump and includes a rotating ring 10 fitted on the pump shaft 4, a non-rotating ring 8 located behind the rotating ring 10, a spring 14, a suction cup 12, and an electromagnetic coil 9. The suction cup 12 is fixed to the non-rotating ring 8, the electromagnetic coil 9 is fixed to the bearing cover 11, and the spring 14 is fitted on the pump shaft 4 and located between the non-rotating ring 8 and the bearing cover 11. During operation, an external circuit generates magnetism to attract the suction cup 12, causing the sealing surface of the non-rotating ring 10 to separate from the sealing surface of the rotating ring. When the pump stops and the power is cut off, the coil 9 loses its magnetism and separates from the suction cup 12 under the action of the spring 14, restoring the sealing surfaces of the non-rotating ring 8 and the rotating ring 10 to a tight fit. Based on the calculation of the compression of the non-rotating ring 8, it is ensured that the sealing surfaces are tightly fitted when the pump stops and disengaged during operation.

[0041] Please see Figures 3 to 5An electromagnetic coil 9 is fixed to the bearing cover 11, and a suction cup 12, which works in conjunction with it to achieve adsorption, is fixed to a non-rotating ring 8. The non-rotating ring 8 is fixed to the suction cup 12, and a rotating ring 10, fitted onto the pump shaft 4, rotates with the pump shaft 4. A permanent magnet disk is coaxially fixed to the bearing cover 11, which is rigidly connected to the bearing bracket 7. A time relay is included in the electromagnetic circuit to control the on / off time of the external circuit.

[0042] In this embodiment, the shutdown seal works in conjunction with the dynamic seal. During operation, the dynamic seal prevents the pump medium from leaking along the pump shaft 4 past the auxiliary impeller chamber 3 and the auxiliary impeller 5. Simultaneously, the external circuit is powered on, and the electromagnetic coil 9 generates a magnetic attraction to the suction cup 12, compressing the spring. This causes the magnetic surface of the electromagnetic coil 9 to adhere to the suction cup 12, preventing wear on the sealing surface and loss of mechanical energy. When shutting down, under the control of the time relay, the external circuit is de-energized 2-3 seconds after the motor is powered off, and the non-rotating ring 8 re-adheres to the sealing surface of the rotating ring 10. This achieves a "non-contact" operation for switching the sealing state, reducing the difficulty of installation and maintenance and the risk of wear. It eliminates the need for a sealing ring, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). It also eliminates the need for a mechanical seal isolation fluid, reducing frictional resistance, and provides good tracking and vibration resistance, with a high tolerance for vibration and misalignment of the pump shaft 4.

[0043] Example 3:

[0044] Please see Figures 6 to 8This utility model provides a maintenance-free centrifugal pump with an integrated permanent magnet seal, including a pump body, a drive mechanism, and a stop seal disposed outside the pump body. The stop seal includes a rotating ring, a non-rotating ring, and a fixed seat. Two rings of magnets with opposite magnetic poles are respectively arranged circumferentially on the non-rotating ring and the fixed seat. The drive mechanism drives the non-rotating ring to rotate, and the magnets on the fixed seat attract the magnets on the non-rotating ring, causing the sealing surface of the non-rotating ring to move and separate from the sealing surface of the rotating ring. The drive mechanism pulls the non-rotating ring to rotate, and the magnets on the fixed seat repel the magnets on the non-rotating ring, causing the sealing surface of the non-rotating ring to move and fit against the sealing surface of the rotating ring. In this embodiment, when the pump stops, the non-rotating ring is rotated by the drive mechanism, thereby changing the magnetism of the magnet on the non-rotating ring. This magnet interacts with the magnet on the fixed base to attract or repel the non-rotating ring, thus enabling its movement. Compared to the electromagnetic drive of an electromagnetic coil, the integrated structure mounted on the fixed base is more stable and reliable, with a longer service life. It achieves "non-contact" operation for switching the sealing state, reducing installation and maintenance difficulty and wear risk. There is no issue of sealing surface wear or mechanical energy loss between the two systems. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It has good tracking and vibration resistance, and a high tolerance for pump shaft sway and misalignment. This maintenance-free centrifugal pump with integrated permanent magnet seal can be used in the self-priming jet device of the above embodiment. The cooperation between the magnet and the drive mechanism drives the non-rotating ring. Preferably, this centrifugal pump also includes a spring for driving the sealing surface of the non-rotating ring to press against the sealing surface of the rotating ring. Preferably, the driving mechanism includes an electric actuator, the output end of which is connected to a transmission sleeve, and the non-rotating ring is coaxially fixedly mounted on the transmission sleeve. The electric actuator drives the transmission sleeve to rotate, and the transmission sleeve drives the non-rotating ring to rotate.

[0045] Please see Figures 6 to 8The fixed base is provided with a drive trajectory hole to limit the driving direction of the drive mechanism. Preferably, the centrifugal pump also includes a pump shaft, and the rotating ring, the non-rotating ring, and the fixed base are all sleeved on the pump shaft. The centrifugal pump also includes a dynamic seal for shaft sealing, the dynamic seal including an impeller, a secondary impeller chamber mounted on the pump body, and a secondary impeller located in the secondary impeller chamber. The impeller and the secondary impeller are both connected to the pump shaft, and the secondary impeller chamber is located on the side of the impeller away from the inlet of the pump body. The side of the impeller near the secondary impeller chamber is provided with secondary blades. A portion of the pump body end face is provided with an inlet and an outlet, and the other end face of the pump body is provided with a pump cover, through which the pump shaft enters the pump body. A pressure cap is installed on the fixed base. In this embodiment, the maintenance-free centrifugal pump with integrated permanent magnet seal includes a pump body 1. The pump body 1 has an inlet at the front end, an outlet on the side, and a pump cover 6 installed at the rear end. An externally driven pump shaft 4 passes through the pump cover 6 and enters the pump body 1. An impeller 2 with a guide flow channel is installed at the front end of the pump shaft 4. A power seal and a shutdown seal are respectively provided inside and outside the pump body 1. The power seal is located between the impeller 2 and the pump cover 6 and includes an auxiliary impeller 5 located between the impeller 2 and the pump cover 6 and sleeved on the pump shaft 4, and an auxiliary blade chamber 3 sleeved outside the auxiliary impeller 5 and cooperating with the pump cover 6. Specifically, the power seal includes an auxiliary blade provided on the back of the impeller 2, an auxiliary impeller chamber 3 located on the rear side of the impeller 2 and installed on the pump body 1, and an auxiliary impeller 5 located in the auxiliary impeller chamber 3 and connected to the pump shaft 4.

[0046] Please see Figures 6 to 8 The shutdown seal is located on the rear side of the pump cover 6 of the centrifugal pump. It includes a fixed seat 9 that is sleeved on the pump shaft 4 of the centrifugal pump and installed on the pump cover 6, a rotating ring 10 that is sleeved on the pump shaft 4, a non-rotating ring 8 behind the rotating ring, a spring 11, a pressure cover 13, and an electric push rod 12 fixed on the non-rotating ring. During operation, the electric push rod 12 is driven by an external circuit to rotate the non-rotating ring 8 and reverse the magnetic pole, so that the sealing surfaces are separated. When the pump stops, the external circuit drives the electric push rod 12 to rotate the non-rotating ring 8 again, and the magnetic pole returns to the initial state. The sealing surfaces of the non-rotating ring 8 and the rotating ring 10 are restored to a tight state.

[0047] Please see Figures 6 to 8This centrifugal pump requires no frequent maintenance, has low mechanical energy loss, does not require mechanical seal isolation fluid, and is highly durable for media that are prone to crystallization / scaling. Among them, the dynamic seal achieves sealing during operation: during operation, the auxiliary blades can reduce the back pressure of the impeller 2 to keep the pump axial force in a balanced state. At the same time, the auxiliary impeller 5 rotates in the auxiliary impeller chamber 3 to form a negative pressure zone, so that the medium in the pump will not leak along the pump shaft 4 across the auxiliary impeller chamber 3 and the auxiliary impeller 5. It also avoids damage to the rear components of the auxiliary impeller 5 by corrosive, high-temperature, and solid particle-containing media. Moreover, the external circuit drives the electric push rod 12 to rotate the non-rotating ring 8 and reverse the magnetic pole. Thus, under the action of magnetic force and spring, the free end of the non-rotating ring 8 moves away from the rotating ring 10, and there will be no problem of sealing surface wear and mechanical energy loss between the two.

[0048] Please see Figures 6 to 8 The shutdown seal achieves sealing during shutdown: when the pump stops, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the two magnetic discs with the same pole to repel and separate. Under the action of the spring 11, the sealing surface on the non-rotating ring 8 tightly fits against the sealing surface of the rotating ring 10. This achieves "non-contact" operation for switching the sealing state, reducing the difficulty of installation and maintenance and the risk of wear. There is no problem of sealing surface wear or mechanical energy loss between the two, eliminating the need for a sealing ring and solving the problem of sealing ring deterioration and failure under high temperature (>150℃). It also eliminates the need for mechanical seal isolation fluid, reducing frictional resistance, and has good tracking and vibration resistance, with a large tolerance for vibration and deflection of the pump shaft 4. This centrifugal pump has high durability for hazardous media such as those that are prone to crystallization, scaling, are stationary at room temperature, flammable, and explosive, and can be widely used in the fields of chemical, metallurgical, and environmental fluid media transportation.

[0049] Please see Figures 6 to 8 The shutdown seal is located on the rear side of the pump cover 6 of the centrifugal pump. It includes a fixed seat 9 fitted onto the pump shaft 4 and mounted on the pump cover 6, a rotating ring 10 fitted onto the pump shaft 4, a non-rotating ring 8 behind the rotating ring, a spring 11, a pressure cap 13, and an electric actuator 12 fixed to the non-rotating ring. During operation, the electric actuator 12 pushes the non-rotating ring 8 to rotate, causing the opposite poles of the two magnets to attract and adhere, thereby separating the sealing surface on the non-rotating ring 8 from the sealing surface of the rotating ring 10. When the pump stops, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the like poles of the two magnets to repel and separate. Under the action of the spring 11, the sealing surface on the non-rotating ring 8 tightly adheres to the sealing surface of the rotating ring 10. Based on the calculation of the compression of the non-rotating ring 8, it ensures that the sealing surface is tightly adhered when the pump stops and disengaged during operation.

[0050] Please see Figures 6 to 8The pump shaft 4 is externally driven after passing through the bearing 14 at its rear end. A permanent magnet disk on the side of the fixed base 9 is coaxially fixedly installed on the fixed base 9, which is rigidly connected to the pump cover 6. A permanent magnet disk on the side of the non-rotating ring 8 is coaxially fixedly installed on the front end of the transmission sleeve, and the transmission sleeve drives the permanent magnet disk to rotate around its axis. A ring of permanent magnets is evenly distributed around the non-rotating ring 8 and the fixed base 9, with adjacent magnets having opposite magnetic poles. When the electric actuator 12 rotates the non-rotating ring 8 by a fixed angle, the magnetic poles can be reversed to change the sealing surface state. The fixed base 9 is provided with an electric actuator track hole to ensure that the rotation angle and axial movement of the non-rotating wheel are accurate each time the electric actuator is pulled.

[0051] Thus, in this embodiment, the contactless switching of the sealing state is achieved by electronically controlling the switching of the magnetic force direction. This eliminates the need for sealing rings and mechanical seal isolation fluid, extending service life. It can operate reliably even at high temperatures and in media containing sediment particles, making it particularly suitable for centrifugal pump applications with frequent start-stop cycles or requiring reliable shutdown seals. The shutdown seal works in conjunction with the dynamic seal. During operation, the dynamic seal prevents the medium inside the pump from leaking along the pump shaft 4 past the auxiliary impeller chamber 3 and the auxiliary impeller 5. Simultaneously, the external circuit is powered on. During operation, the electric actuator 12 pushes the non-rotating ring 8 to rotate, causing the opposite poles of the two magnets to attract and adhere, thereby separating the sealing surface on the non-rotating ring 8 from the sealing surface of the rotating ring 10. When stopping, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the like poles of the two magnets to repel and separate. Under the action of the spring 11, the sealing surface on the non-rotating ring 8 tightly adheres to the sealing surface of the rotating ring 10. It achieves "non-contact" operation for switching between sealing states, reducing the difficulty of installation and maintenance and the risk of wear. There will be no problem of sealing surface wear or mechanical energy loss between the two. There is no need to set a sealing ring, which solves the problem of sealing ring deterioration and failure under high temperature (>150℃). There is no need for mechanical seal isolation fluid, which reduces frictional resistance. It has good followability and shock resistance, and has a large tolerance for the vibration and deflection of pump shaft 4.

[0052] Example 4:

[0053] Please see Figures 9 to 11This utility model provides a maintenance-free centrifugal pump with a permanent magnet seal, including a pump body and a pump shaft, as well as a stop seal and a bearing assembly. The pump shaft is externally driven by the bearing assembly. Both the stop seal and the bearing assembly are located outside the pump body. The stop seal includes a rotating ring and a non-rotating ring, both sleeved on the pump shaft. The non-rotating ring and the bearing assembly each have two rings of magnets with opposite magnetic poles arranged circumferentially. The driving mechanism pushes the non-rotating ring to rotate, and the magnets on the bearing assembly attract the magnets on the non-rotating ring, causing the sealing surface of the non-rotating ring to move and separate from the sealing surface of the rotating ring. The driving mechanism pulls the non-rotating ring to rotate, and the magnets on the bearing assembly repel the magnets on the non-rotating ring, causing the sealing surface of the non-rotating ring to move and fit against the sealing surface of the rotating ring. In this embodiment, when the pump stops, the non-rotating ring is rotated by a drive mechanism, thereby changing the magnetism of the magnet on the non-rotating ring. This magnet interacts with the magnet on the bearing assembly to attract or repel the non-rotating ring, thus enabling its movement. Compared to electromagnetic drive by an electromagnetic coil, the integrated structure mounted on the fixed base is more stable and reliable, with a longer service life. It achieves "non-contact" operation for switching the sealing state, reducing installation and maintenance difficulty and wear risk. There is no issue of sealing surface wear or mechanical energy loss between the two systems. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It has good tracking and vibration resistance, and a high tolerance for pump shaft sway and misalignment. This maintenance-free centrifugal pump with a permanent magnet seal can be used in the self-priming jet device of the above embodiment. The cooperation between the magnet and the drive mechanism drives the non-rotating ring. Preferably, the bearing assembly includes a bearing through which the pump shaft passes and a bearing cap for fixing the bearing, wherein one ring of the magnet is fixedly mounted on the bearing cap. Preferably, the drive mechanism includes an electric actuator, the output end of which is connected to a transmission sleeve. The non-rotating ring is coaxially fixedly mounted on the transmission sleeve. The electric actuator drives the transmission sleeve to rotate, and the transmission sleeve drives the non-rotating ring to rotate. The rotating ring, the non-rotating ring, and the bearing assembly are arranged sequentially along the length of the pump shaft. Preferably, a bearing bracket is also mounted outside the pump body, and the bearing assembly is mounted on the bearing bracket. The bearing bracket has space for housing two coils of the magnet.

[0054] Please see Figures 9 to 11This centrifugal pump also includes a dynamic seal for shaft sealing. The dynamic seal includes an impeller, a secondary impeller chamber mounted on the pump body, and a secondary impeller located within the secondary impeller chamber. Both the impeller and the secondary impeller are connected to the pump shaft. The secondary impeller chamber is located on the side of the impeller away from the inlet of the pump body. The impeller has secondary blades on the side closest to the secondary impeller chamber. A portion of the pump body has an inlet and an outlet, and the other end face of the pump body has a pump cover. The pump shaft passes through the pump cover and enters the pump body. In this embodiment, the maintenance-free centrifugal pump with permanent magnet seal includes a pump body 1. The pump body 1 has an inlet at the front end, an outlet on the side, and a pump cover 6 installed at the rear end. An externally driven pump shaft 4 passes through the pump cover 6 and enters the pump body 1. An impeller 2 with a guide flow channel is installed at the front end of the pump shaft 4. A power seal and a shutdown seal are respectively provided inside and outside the pump body 1. The power seal is located between the impeller 2 and the pump cover 6 and includes an auxiliary impeller 5 located between the impeller 2 and the pump cover 6 and sleeved on the pump shaft 4, and an auxiliary blade chamber 3 sleeved outside the auxiliary impeller 5 and cooperating with the pump cover 6. Specifically, the power seal includes an auxiliary blade provided on the back of the impeller 2, an auxiliary impeller chamber 3 located on the rear side of the impeller 2 and installed on the pump body 1, and an auxiliary impeller 5 located in the auxiliary impeller chamber 3 and connected to the pump shaft 4.

[0055] Please see Figures 9 to 11 The shutdown seal is located between the pump cover 6 and the bearing cap 11 of the centrifugal pump. It includes a rotating ring 10 fitted on the pump shaft 4, a non-rotating ring 8 behind the rotating ring, two permanent magnets 9 fixed on the non-rotating ring 8 and the bearing cap 11 respectively, and an electric actuator 12 fixed on the non-rotating ring 8. During operation, the electric actuator 12 pushes the non-rotating ring 8 to rotate, causing the opposite poles of the two magnets to attract and adhere to each other, thereby causing the sealing surface on the non-rotating ring 8 to separate from the sealing surface of the rotating ring 10. When the pump stops, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the like poles of the two magnets to repel and separate, causing the sealing surface on the non-rotating ring 8 to adhere tightly to the sealing surface of the rotating ring 10.

[0056] Please see Figures 9 to 11 This centrifugal pump requires no frequent maintenance, has low mechanical energy loss, does not require mechanical seal isolation fluid, and is highly durable for media that are prone to crystallization / scaling. Among them, the dynamic seal achieves sealing during operation: during operation, the auxiliary blades can reduce the back pressure of the impeller 2 to keep the pump axial force in a balanced state. At the same time, the auxiliary impeller 5 rotates in the auxiliary impeller chamber 3 to form a negative pressure zone, so that the medium in the pump will not leak along the pump shaft 4 across the auxiliary impeller chamber 3 and the auxiliary impeller 5. It also avoids damage to the rear components of the auxiliary impeller 5 by corrosive, high-temperature, and solid particle-containing media. Moreover, the external circuit drives the electric push rod 12 to rotate the non-rotating ring 8 and reverse the magnetic pole. Thus, under the action of magnetic force and spring, the free end of the non-rotating ring 8 moves away from the rotating ring 10, and there will be no problem of sealing surface wear and mechanical energy loss between the two.

[0057] Please see Figures 9 to 11 The shutdown seal achieves sealing during shutdown: when the pump stops, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the two magnetic discs with the same poles to repel and separate, resulting in a tight seal between the sealing surface of the non-rotating ring 8 and the sealing surface of the rotating ring 10. This achieves a "non-contact" operation for switching the sealing state, reducing the difficulty of installation and maintenance, and minimizing wear risks. There is no wear on the sealing surface or loss of mechanical energy between the two, eliminating the need for a sealing ring and solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). It also eliminates the need for mechanical seal isolation fluid, reducing frictional resistance, and provides excellent tracking and vibration resistance, with a high tolerance for vibration and misalignment of the pump shaft 4. This centrifugal pump exhibits high durability for hazardous media such as those prone to crystallization, scaling, those that are stable at room temperature, and those that are flammable or explosive, and can be widely used in the chemical, metallurgical, and environmental fluid transport fields.

[0058] Please see Figures 9 to 11 The shutdown seal is located between the pump cover 6 and the bearing cap 11 of the centrifugal pump. It includes a rotating ring 10 fitted onto the pump shaft 4, a non-rotating ring 8 behind the rotating ring, two permanent magnet discs 9 fixed to the non-rotating ring 8 and the bearing cap 11 respectively, and an electric actuator 12 fixed to the non-rotating ring 8. During operation, the electric actuator 12 pushes the non-rotating ring 8 to rotate, causing the opposite poles of the two magnet discs to attract and adhere, thereby separating the sealing surface on the non-rotating ring 8 from the sealing surface of the rotating ring 10. When the pump stops, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the like poles of the two magnet discs to repel and separate, causing the sealing surface on the non-rotating ring 8 to tightly adhere to the sealing surface of the rotating ring 10. Based on the calculation of the compression of the non-rotating ring 8, it ensures that the sealing surfaces are tightly fitted when the pump stops and disengaged during operation.

[0059] Please see Figures 9 to 11 In this embodiment, the rear end of the pump shaft 4 passes through the bearing 14 and is externally driven. A permanent magnet disk on the bearing cover 11 side is coaxially fixedly installed on the bearing cover 11, which is rigidly connected to the bearing bracket 7. A permanent magnet disk on the non-rotating ring 8 side is coaxially fixedly installed on the front end of the transmission sleeve, and the transmission sleeve drives the permanent magnet disk to rotate around its axis. A ring of permanent magnets is evenly distributed circumferentially on both the non-rotating ring 8 and the bearing cover 11, with adjacent magnets having opposite magnetic poles. When the electric actuator 12 rotates the non-rotating ring 8 by a fixed angle, the magnetic poles can be reversed to change the sealing surface state.

[0060] Thus, in this embodiment, the contactless switching of the sealing state is achieved by electronically controlling the switching of the magnetic force direction. This eliminates the need for sealing rings and mechanical seal isolation fluid, extending service life. It can operate reliably even at high temperatures and in media containing sediment particles, making it particularly suitable for centrifugal pump applications with frequent start-stop cycles or requiring reliable shutdown seals. The shutdown seal works in conjunction with the dynamic seal. During operation, the dynamic seal prevents the medium inside the pump from leaking along the pump shaft 4 past the auxiliary impeller chamber 3 and the auxiliary impeller 5. Simultaneously, the external circuit is powered on. During operation, the electric actuator 12 pushes the non-rotating ring 8 to rotate, causing the opposite poles of the two magnets to attract and adhere, thereby separating the sealing surface of the non-rotating ring 8 from the sealing surface of the rotating ring 10. When stopping, the electric actuator 12 pulls the non-rotating ring 8 to rotate, causing the like poles of the two magnets to repel and separate, resulting in a tight seal between the sealing surface of the non-rotating ring 8 and the sealing surface of the rotating ring 10. It achieves "non-contact" operation for switching between sealing states, reducing the difficulty of installation and maintenance and the risk of wear. There will be no problem of sealing surface wear or mechanical energy loss between the two. There is no need to set a sealing ring, which solves the problem of sealing ring deterioration and failure under high temperature (>150℃). There is no need for mechanical seal isolation fluid, which reduces frictional resistance. It has good followability and shock resistance, and has a large tolerance for the vibration and deflection of pump shaft 4.

[0061] Example 5:

[0062] Please see Figures 12 to 14This utility model provides a split-type electromagnetic clutch maintenance-free centrifugal pump, including a pump body. The pump body is provided with a stop seal. The stop seal includes a rotating ring, a non-rotating ring, a suction cup, a split seat, and a magnetic supply structure. The split seat includes a fixed end and a movable end. The suction cup is fixed to the non-rotating ring through the movable end. The magnetic supply structure attracts the suction cup. The sealing surface of the non-rotating ring moves with the suction cup to separate from the sealing surface of the rotating ring. When the magnetic supply structure does not attract the suction cup, the sealing surface of the non-rotating ring returns to its original position to fit against the sealing surface of the rotating ring. In this embodiment, during shutdown, the movement of the non-rotating ring can be achieved more stably through the cooperation of the magnetic supply structure and the suction cup, realizing a "non-contact" operation for switching the sealing state. This reduces the difficulty of installation and maintenance, as well as the risk of wear. There is no issue of sealing surface wear or mechanical energy loss between the two components. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It exhibits good tracking and vibration resistance, and has a high tolerance for pump shaft vibration and misalignment. This split-type electromagnetic clutch maintenance-free centrifugal pump can be used in the self-priming jet device of the above embodiment. The function of the magnetic supply structure is to provide magnetic attraction to the suction cup, thereby driving the non-rotating ring. There are many ways to supply magnets to the magnetic supply structure; for example, the electromagnetic coil in this embodiment can also be used, or the permanent magnet schemes of embodiments two and three can be employed. Preferably, the magnetizing structure includes an electromagnetic coil connected to an external circuit. The external circuit supplies power to the electromagnetic coil, which generates magnetism to attract the suction cup. When the external circuit is de-energized, the electromagnetic coil loses its magnetism and its attraction to the suction cup, causing the suction cup to reset and thus resetting the non-rotating ring. The centrifugal pump also includes a time relay electrically connected to the external circuit.

[0063] Please see Figures 12 to 14This centrifugal pump also includes a dynamic seal for shaft sealing, comprising an impeller, an auxiliary impeller chamber mounted on the pump body, and an auxiliary impeller located within the auxiliary impeller chamber. Both the impeller and the auxiliary impeller are connected to the pump shaft. The auxiliary impeller chamber is located on the side of the impeller away from the pump body inlet. The impeller has auxiliary blades on its side closest to the auxiliary impeller chamber. This centrifugal pump also includes a pump shaft and a bearing cover. Both the rotating ring and the non-rotating ring are fitted onto the pump shaft, and the magnetizing structure is fixed to the bearing cover. The split seat also includes a spring for resetting the non-rotating ring, the spring being located on the pump shaft and between the non-rotating ring and the bearing cover. A portion of the pump body's end face has an inlet and an outlet, and the other end face of the pump body has a pump cover. The pump shaft passes through the pump cover and enters the pump body. The fixed end is fixed to the pump cover. In this embodiment, the split-type electromagnetic clutch maintenance-free centrifugal pump includes a pump body 1. The pump body 1 has an inlet at the front end, an outlet on the side, and a pump cover 6 installed at the rear end. An externally driven pump shaft 4 passes through the pump cover 6 and enters the pump body 1. An impeller 2 with a guide flow channel is installed at the front end of the pump shaft 4. The pump body 1 is provided with a power seal and a shutdown seal on its inner and outer sides, respectively. The power seal is located between the impeller 2 and the pump cover 6 and includes an auxiliary impeller 5 located between the impeller 2 and the pump cover 6 and sleeved on the pump shaft 4, and an auxiliary blade chamber 3 sleeved on the outside of the auxiliary impeller 5 and cooperating with the pump cover 6. Specifically, the power seal includes an auxiliary blade provided on the back of the impeller 2, an auxiliary impeller chamber 3 located on the rear side of the impeller 2 and installed on the pump body 1, and an auxiliary impeller 5 located in the auxiliary impeller chamber 3 and connected to the pump shaft 4.

[0064] Please see Figures 12 to 14 The shutdown seal is located on the rear side of the pump cover 6 of the centrifugal pump, including a rotating ring 10 fitted on the pump shaft 4 of the centrifugal pump, a non-rotating ring 8 located behind the rotating ring 10, a spring 15, a suction cup 14, and an electromagnetic coil 9. The split seat 12 consists of three parts: a fixed end, a movable end, and a small spring. The fixed end is fixed to the pump cover 6. The suction cup 14 is fixed to the non-rotating ring 8 through the movable end of the split seat 12. The electromagnetic coil 9 is fixed to the bearing cover 11. The spring 15 is fitted on the pump shaft 4 and located between the non-rotating ring 8 and the bearing cover 11. During operation, the external circuit generates magnetism to attract the suction cup 14, causing the sealing surface of the non-rotating ring 10 to separate from the sealing surface of the rotating ring. When the pump stops and the power is cut off, the coil 9 loses its magnetism and separates from the suction cup 12 under the action of the spring 15, and the sealing surfaces of the non-rotating ring 8 and the rotating ring 10 return to a tight state.

[0065] Please see Figures 12 to 14This centrifugal pump requires no frequent maintenance, has low mechanical energy loss, does not require mechanical seal isolation fluid, and is highly durable for media that are prone to crystallization / scaling. Among them, the dynamic seal achieves sealing during operation: during operation, the auxiliary blades can reduce the back pressure of the impeller 2 to keep the pump axial force in a balanced state. At the same time, the auxiliary impeller 5 rotates in the auxiliary impeller chamber 3 to form a negative pressure zone, so that the medium in the pump will not leak along the pump shaft 4 across the auxiliary impeller chamber 3 and the auxiliary impeller 5. It also avoids damage to the rear components of the auxiliary impeller 5 by corrosive, high-temperature, and solid particle-containing media. Moreover, the electromagnetic coil 9, which generates magnetism when energized, attracts the suction cup 14 to make the two completely fit together, thereby compressing the spring 15 and moving the free end of the non-rotating ring 8 away from the rotating ring 10. There will be no problem of sealing surface wear or mechanical energy loss between the two.

[0066] Please see Figures 12 to 14 The shutdown seal achieves sealing during shutdown: when the pump stops, the electromagnetic coil 9, demagnetized and disconnected from the suction cup 14, separates from the coil 9 under the pressure of the spring 15. The free end of the non-rotating ring 8 moves towards the rotating ring 10 until it re-adheres to the sealing surface of the rotating ring 10, achieving a seal at the joint. This reduces the difficulty of installation and maintenance, and the risk of wear. There is no wear on the sealing surface or loss of mechanical energy between the two components. No sealing ring is required, solving the problem of sealing ring deterioration and failure at high temperatures (>150℃). No mechanical seal isolation fluid is needed, reducing frictional resistance. It has good tracking and vibration resistance, and a large tolerance for vibration and misalignment of the pump shaft 4. This centrifugal pump has high durability for hazardous media such as those prone to crystallization, scaling, those that are stationary at room temperature, and those that are flammable or explosive. It can be widely used in the chemical, metallurgical, and environmental fluid transport fields.

[0067] Please see Figures 12 to 14 The shutdown seal is located on the rear side of the pump cover 6 of the centrifugal pump, including a rotating ring 10 fitted on the pump shaft 4 of the centrifugal pump, a non-rotating ring 8 located behind the rotating ring 10, a spring 15, a suction cup 14, and an electromagnetic coil 9. The split seat 12 consists of three parts: a fixed end, a movable end, and a small spring. The fixed end is fixed to the pump cover 6. The suction cup 14 is fixed to the non-rotating ring 8 through the movable end of the split seat 12. The electromagnetic coil 9 is fixed to the bearing cover 11. The spring 15 is fitted on the pump shaft 4 and located between the non-rotating ring 8 and the bearing cover 11. During operation, the external circuit generates magnetism to attract the suction cup 14, causing the sealing surface of the non-rotating ring 10 to separate from the sealing surface of the rotating ring. When the pump stops and the power is cut off, the coil 9 loses its magnetism and separates from the suction cup 12 under the action of the spring 15, and the sealing surfaces of the non-rotating ring 8 and the rotating ring 10 return to a tight state.

[0068] Please see Figures 12 to 14The electromagnetic coil 9 is fixed to the bearing cover 11, and the suction cup 14, which cooperates with it to achieve the adsorption effect, is fixed to the non-rotating ring 8. The non-rotating ring 8 is fixed to the suction cup 14, and the rotating ring 10, which is sleeved on the pump shaft 4, rotates with the pump shaft 4. The split seat 12 consists of three parts: a fixed end, a movable end, and a small spring. The fixed end is fixed to the pump cover 6, and the suction cup 14 is fixed to the non-rotating ring 8 through the movable end of the split seat 12. The spring ensures that the gap between the suction cup 14 and the sealing surface is adjustable. A time relay is set in the electromagnetic circuit to control the on and off time of the external circuit.

[0069] Thus, in this embodiment, the centrifugal pump does not experience sealing surface wear or mechanical energy loss during operation. It achieves a seal during shutdown, preventing wear and corrosion of the pump shaft 4 by the medium. No sealing ring or mechanical seal isolation fluid is required, and it can operate reliably even at high temperatures and in media containing sediment particles. The shutdown seal works in conjunction with the dynamic seal. During operation, the dynamic seal prevents the medium inside the pump from leaking along the pump shaft 4 past the auxiliary impeller chamber 3 and the auxiliary impeller 5. Simultaneously, the external circuit is powered on, and the electromagnetic coil 9 generates a magnetic attraction to the suction cup 14, compressing the spring 15. This causes the magnetic surface of the electromagnetic coil 9 to adhere to the suction cup 14, preventing sealing surface wear and mechanical energy loss. During shutdown, under the control of the time relay, the external circuit is de-energized 2-3 seconds after the motor is powered off, and the non-rotating ring 8 re-adheres to the sealing surface of the rotating ring 10. It achieves "non-contact" operation for switching between sealing states, reducing the difficulty of installation and maintenance and the risk of wear. There will be no problem of sealing surface wear or mechanical energy loss between the two. There is no need to set a sealing ring, which solves the problem of sealing ring deterioration and failure under high temperature (>150℃). There is no need for mechanical seal isolation fluid, which reduces frictional resistance. It has good followability and shock resistance, and has a large tolerance for the vibration and deflection of pump shaft 4.

[0070] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A split-type electromagnetic clutch maintenance-free centrifugal pump, comprising a pump body, characterized in that: The pump body is provided with a shutdown seal, which includes a rotating ring, a non-rotating ring, a suction cup, a split seat, and a magnetic supply structure. The split seat includes a fixed end and a movable end. The suction cup is fixed to the non-rotating ring through the movable end. The magnetic supply structure attracts the suction cup. The sealing surface of the non-rotating ring moves with the suction cup to separate from the sealing surface of the rotating ring. When the magnetic supply structure does not attract the suction cup, the sealing surface of the non-rotating ring returns to its original position to fit against the sealing surface of the rotating ring.

2. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 1, characterized in that: It also includes a pump shaft and a bearing cover, with the rotating ring and the non-rotating ring both fitted onto the pump shaft, and the magnetizing structure fixed to the bearing cover.

3. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 2, characterized in that: The split seat also includes a spring for resetting the non-rotating ring, the spring being disposed on the pump shaft and located between the non-rotating ring and the bearing cap.

4. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 2, characterized in that: One end face of the pump body is provided with an inlet and an outlet, and the other end face of the pump body is provided with a pump cover. The pump shaft passes through the pump cover and enters the pump body.

5. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 4, characterized in that: The fixed end is fixed to the pump cover.

6. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 2, characterized in that: It also includes a dynamic seal for shaft sealing, the dynamic seal comprising an impeller, an auxiliary impeller chamber mounted on the pump body, and an auxiliary impeller located within the auxiliary impeller chamber, both the impeller and the auxiliary impeller being connected to the pump shaft, the auxiliary impeller chamber being located on the side of the impeller away from the inlet of the pump body.

7. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 6, characterized in that: The impeller has secondary blades on the side near the secondary impeller chamber.

8. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 1, characterized in that: The magnetizing structure includes an electromagnetic coil connected to an external circuit. The external circuit supplies power to the electromagnetic coil, which generates magnetism to attract the chuck. When the external circuit is de-energized, the electromagnetic coil loses its magnetism and its attraction to the chuck, causing the chuck to reset and thus resetting the non-rotating ring.

9. The split-type electromagnetic clutch maintenance-free centrifugal pump as described in claim 8, characterized in that: It also includes a time relay electrically connected to the external circuit.

10. A self-priming jetting device, characterized in that: Including the split-type electromagnetic clutch maintenance-free centrifugal pump as described in any one of claims 1-9.

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