Positive pressure explosion-proof magnetic levitation blower

Abstract

The application is suitable for the technical field of magnetic suspension blower, and provides a positive pressure explosion-proof magnetic suspension blower, which comprises a volute, an impeller, a sealing disc, a motor, an upper section of a machine shell and a first positive pressure cabin body; the impeller is arranged at the center of the volute; the impeller is connected with the motor; the upper section of the machine shell is the upper half of the machine shell of the motor; the first positive pressure cabin body is located below the impeller; the motor is fixed in the first positive pressure cabin body through the upper section of the machine shell; the upper section of the machine shell is fixed at a height higher than the upper surface of the first positive pressure cabin body; the sealing disc is connected with the volute to seal the volute and is connected with the upper section of the machine shell; the upper section of the machine shell, the sealing disc and the impeller form a heightening space, and the heightening space is in a normal pressure state. The application can prevent dangerous gas from entering the motor through the connection between the impeller and the motor, further prevent the magnetic suspension blower from exploding, and improve safety.

Description

Technical Field

[0001] This application belongs to the field of magnetic levitation blower technology, and particularly relates to a positive pressure explosion-proof magnetic levitation blower. Background Technology

[0002] With the rapid popularization of magnetic levitation technology, the application fields of magnetic levitation blowers are constantly expanding, such as in hazardous locations like petroleum and chemical industries. Operations in hazardous locations require magnetic levitation blowers to meet explosion-proof requirements. Due to the complex structure of magnetic levitation motors, it is difficult to meet explosion-proof requirements using ordinary explosion-proof structures, posing safety hazards.

[0003] However, existing positive pressure explosion-proof technology simply places the magnetic levitation blower in a positive pressure environment. The inventors discovered that during blower operation, hazardous gases may enter the intake pipe, and some of these gases can enter the motor through the impeller-motor connection, potentially causing an explosion. Therefore, preventing hazardous gases from entering the motor through the impeller-motor connection and further preventing explosions of the magnetic levitation blower, thus improving safety, is an urgent problem to be solved. Summary of the Invention

[0004] In view of this, this application provides a positive pressure explosion-proof magnetic levitation blower, which can prevent dangerous gases from entering the motor through the connection between the impeller and the motor from the air inlet pipe, further preventing the magnetic levitation blower from exploding and improving the safety of the magnetic levitation blower during operation.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] In a first aspect, embodiments of this application provide a positive pressure explosion-proof magnetic levitation blower, including a volute, an impeller, a sealing disc, a motor, an upper casing, and a first positive pressure chamber;

[0007] The impeller is located in the center of the volute; the impeller is connected to the motor; the upper casing is the upper half of the motor casing;

[0008] The first positive pressure chamber is located below the impeller; the motor is fixed inside the first positive pressure chamber via the upper casing; the upper casing is fixedly higher than the upper surface of the first positive pressure chamber.

[0009] The sealing disc is connected to the volute to seal it, and is also connected to the upper casing. The upper casing, sealing disc, and impeller form an elevated space, which is under normal pressure.

[0010] In some embodiments, the upper housing includes a support structure, the support structure includes a plurality of protrusions; there are gaps between the protrusions; the support space includes gaps;

[0011] The sealing disc is connected to the elevated structure.

[0012] In some embodiments, the upper housing includes an upper housing shell; a raised structure is disposed on the upper surface of the upper housing shell; and protrusions are disposed in a circular array on the upper surface of the upper housing shell.

[0013] The upper casing has a first through hole, through which the motor's main shaft passes and is rigidly connected to the impeller.

[0014] In some embodiments, the sealing disc is stepped, including a first step, a second step, a third step, a fourth step, and a first groove;

[0015] The second and fourth steps are located on either side of the first step; the upper surface of the first step is higher than the upper surfaces of the second and fourth steps.

[0016] The third step connects to the second step and is located at the end of the stepped structure, near the center of the sealing disc; the upper surface of the second step is higher than the upper surface of the third step.

[0017] The first groove is located on the lower surface of the sealing disc; the protrusion is installed in the first groove, and the height of the protrusion is greater than the depth of the first groove.

[0018] In some embodiments, the upper surface of the second step is an inclined plane; the inclined plane has a first preset angle θ.

[0019] In some embodiments, the positive pressure explosion-proof magnetic levitation blower also includes a labyrinth sealing disc;

[0020] The labyrinth seal disk surrounds the lower end of the impeller and is located at the rigid connection point between the motor's main shaft, which passes through the first through hole and the impeller, and connects with the third step of the seal disk.

[0021] In some embodiments, the motor is installed inside a housing; the housing includes an upper housing section and a lower housing section.

[0022] The upper and lower housings secure the motor.

[0023] The upper casing is fastened to the first positive pressure chamber via a connecting plate.

[0024] In some embodiments, the positive pressure explosion-proof magnetic levitation blower further includes a cabinet, an air intake unit, and a pressure relief unit;

[0025] The cabinet includes a positive pressure chamber and an atmospheric pressure chamber; the positive pressure chamber includes a first positive pressure chamber.

[0026] The blower structure includes a volute, an impeller, and a sealing disc; the blower structure is installed inside the atmospheric pressure chamber; the atmospheric pressure chamber is under atmospheric pressure.

[0027] The air intake unit is installed on the outside of the cabinet and is used to provide positive pressure gas to the first positive pressure chamber;

[0028] The pressure relief unit is installed on the outside of the cabinet and is used to relieve pressure when the pressure in the first positive pressure chamber exceeds a first pressure threshold.

[0029] In some embodiments, the positive pressure chamber further includes a second positive pressure chamber and a third positive pressure chamber; the second positive pressure chamber and the third positive pressure chamber are arranged side by side; the first positive pressure chamber, the second positive pressure chamber and the third positive pressure chamber are arranged separately in the cabinet;

[0030] The first, second, and third positive pressure chambers are connected and are all in a positive pressure state.

[0031] In some embodiments, the positive pressure explosion-proof magnetic levitation blower also includes a PLC control unit and a frequency converter;

[0032] The PLC control unit is installed in the second positive pressure chamber, and the magnetic levitation blower and frequency converter are controlled by the PLC control unit.

[0033] The frequency converter is installed in the third positive pressure chamber and is used to adjust the speed of the motor.

[0034] The beneficial effects of this application embodiment are as follows: by installing the blower motor in the positive pressure chamber and reasonably setting the connection relationship between the volute, impeller, sealing plate, and motor, and setting the upper section of the casing to a fixed height above the upper surface of the first positive pressure chamber, the upper section of the casing, sealing plate, and impeller form an elevated space under normal pressure. When the blower is running, if a small amount of dangerous gas enters the intake pipe, most of the gas will be pressurized by the high-speed rotation of the impeller and discharged from the exhaust position. Since the pressure of the chamber where the motor is located is higher than the pressure of the elevated space, a small amount of gas will be discharged from the elevated space, preventing dangerous gas from entering the motor. This prevents external dangerous gas from entering the chamber and contacting the blower motor, further preventing the magnetic levitation blower from exploding and improving the safety of the magnetic levitation blower during operation. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of a positive pressure explosion-proof magnetic levitation blower provided in an embodiment of this application;

[0037] Figure 2 A schematic diagram illustrating the airflow direction during operation of a positive pressure explosion-proof magnetic levitation blower provided in an embodiment of this application;

[0038] Figure 3This is a schematic diagram of the upper casing provided in an embodiment of this application;

[0039] Figure 4 This is a schematic diagram of the structure of the sealing disc provided in an embodiment of this application;

[0040] Figure 5 A schematic diagram of the structure of the impeller and motor connection, including the labyrinth sealing disc, provided for an embodiment of this application;

[0041] Figure 6 A cross-sectional structural schematic diagram of a positive pressure explosion-proof magnetic levitation blower provided in an embodiment of this application;

[0042] Figure 7 A schematic diagram of the overall structure of a positive pressure explosion-proof magnetic levitation blower, including a first positive pressure chamber, provided for an embodiment of this application;

[0043] Figure 8 A schematic diagram of the overall structure of a positive pressure explosion-proof magnetic levitation blower, including a second positive pressure chamber and a third positive pressure chamber, provided for embodiments of this application. Detailed Implementation

[0044] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0045] To make the purpose, technical solution, and advantages of this application clearer, the following will be described in conjunction with the appendix. Figure 1 and Figure 2 The following is an explanation using specific examples.

[0046] Explanation of reference numerals in the attached drawings: 1. Volute; 2. Impeller; 3. Sealing disc; 31. First step; 32. Second step; 33. Third step; 34. Fourth step; 35. First groove; 4. Motor; 5. Upper casing; 51. Elevated structure; 52. Upper casing shell; 521. First through hole; 6. First positive pressure chamber; 61. Connecting disc; 7. Inlet cone; 8. Inlet guide shell; 9. Labyrinth sealing disc; 10. Lower casing; 11. Cabinet; 12. Inlet unit; 13. Pressure relief unit; 14. Second positive pressure chamber; 15. Third positive pressure chamber; 16. First cabinet panel; 17. First cabinet door; 18. First pressure test point; 19. PLC control unit; 20. Frequency converter; 21. Operation panel; 22. Alarm unit.

[0047] See Figure 1 and Figure 2This application provides a positive pressure explosion-proof magnetic levitation blower, including a volute 1, an impeller 2, a sealing disc 3, a motor 4, an upper casing 5, and a first positive pressure chamber 6.

[0048] Impeller 2 is located in the center of volute 1; impeller 2 is connected to motor 4; upper casing 5 is the upper part of motor 4 casing.

[0049] The first positive pressure chamber 6 is located below the impeller 2; the motor 4 is fixed inside the first positive pressure chamber 6 through the upper casing 5; the upper casing 5 is fixedly higher than the upper surface of the first positive pressure chamber 6.

[0050] The sealing disc 3 is connected to the volute 1 to seal the volute 1 and is connected to the upper casing 5; the upper casing 5, the sealing disc 3 and the impeller 2 form an elevated space, which is under normal pressure.

[0051] The intake cone 7 is mounted on the intake guide shell 8, and the impeller 2 is placed inside the intake guide shell 8. The bottom edge of the intake guide shell 8 is connected to the volute 1. External air enters through the intake cone 7 and flows along the intake guide shell 8 to the impeller 2. The impeller 2 is connected to the motor 4, which drives the impeller 2 to rotate at high speed to pressurize the external air. The pressurized air is then discharged into the desired environment through the volute 1.

[0052] The gas entering the intake cone 7 must be a safe gas source. If dangerous gas enters the intake cone 7, during the operation of the magnetic levitation blower, some gas will be discharged from the volute 1, and a small portion will enter the gap between the impeller 2 and the sealing disc 3, and then into the gap formed by the connection between the impeller 2 and the motor 4, thus entering the motor 4. Even a small amount of dangerous gas could cause an explosion. Therefore, by installing the blower motor 4 inside the positive pressure chamber and setting an upper casing 5, which is fixedly higher than the upper surface of the first positive pressure chamber 6, the upper casing 5, the sealing disc 3, and the impeller 2 form an elevated space under normal pressure. Figure 2 As shown, when the fan is running, if dangerous gas enters the intake pipe, most of the gas will be pressurized by the high-speed rotation of impeller 2 and discharged from the exhaust position, such as... Figure 2 As shown by the solid arrow in the image, because the pressure in the first positive pressure chamber 6, where the motor 4 is located, is higher than the pressure in the elevated space under normal pressure, a small amount of gas will be discharged from the elevated space, such as... Figure 2 As shown by the dotted arrow, this prevents dangerous gases from entering the motor 4 and prevents external dangerous gases from entering the cabin and coming into contact with the blower motor 4, further preventing the magnetic levitation blower from exploding and improving the safety of the magnetic levitation blower during operation.

[0053] For example, such as Figure 3As shown, the upper housing 5 includes a support structure 51 and an upper housing shell 52. The support structure 51 includes a plurality of protrusions; there are gaps between the protrusions; the support space includes the gaps.

[0054] The bumps are fan-shaped, so the gaps between the bumps are also fan-shaped. The inner side of the gap has a short opening, and the outer side has a long opening. When gas passes through the gap, the opening of the gap becomes larger and larger, which is conducive to the gas discharge.

[0055] The sealing disc 3 is connected to the raised structure 51, which supports the sealing disc 3, thereby connecting the gap between the protrusions with the external space to form an atmospheric pressure layer.

[0056] The raised structure 51 is installed on the upper surface of the upper housing 52; the protrusions are arranged in a circular array on the upper surface of the upper housing 52. Each protrusion has a screw hole, and the sealing disc 3 is connected to the raised structure 51 by screws.

[0057] The upper housing 52 has a first through hole 521 through which the main shaft of the motor 4 passes and is rigidly connected to the impeller 2. The rigid connection between the main shaft of the motor 4 and the impeller 2 can be achieved using bolts.

[0058] The pressure inside the motor 4 is greater than the pressure in the elevated space. Due to the pressure difference, the dangerous gas will be discharged to the outside through the gaps evenly distributed on the casing, and will not enter the motor 4 through the gap between the main shaft and the first through hole.

[0059] For example, the sealing disc 3 is used to seal the bottom surface of the volute 1, and is generally circular. See the cross-sectional schematic diagram. Figure 4 The sealing disc 3 is stepped, including a first step 31, a second step 32, a third step 33, a fourth step 34 and a first groove 35.

[0060] The second step 32 and the fourth step 34 are respectively located on both sides of the first step 31; the upper surface of the first step 31 is higher than the upper surfaces of the second step 32 and the fourth step 34. The third step 33 connects to the second step 32 and is located at the end of the step, close to the center of the sealing disk 3; the upper surface of the second step 32 is higher than the upper surface of the third step 33. The first groove 35 is located on the lower surface of the sealing disk 3; a protrusion is installed in the first groove 35, and the height of the protrusion is greater than the depth of the first groove.

[0061] The upper surface of the second step 32 is an inclined plane with a first preset angle θ. The first preset angle θ is adapted to the profile of the contacting impeller 2. The fourth step 34 has a first preset height from the first step 31, which can be equal to... Figure 2The thickness h1 of the volute 1 shown is shown. The third step 33 to the second step 32 has a third preset height. The lower surface of the sealing disc 3 to the bottom of the first groove 35 has a fourth preset height, which is the depth of the first groove.

[0062] The upper surface of the second step 32 is an inclined plane. The streamlined inclined plane can be adapted to the impeller 2, leaving a suitable operating space for the impeller 2 and reducing gas collision.

[0063] For example, the positive pressure explosion-proof magnetic levitation blower also includes a labyrinth sealing disc 9, such as Figure 5 As shown. The labyrinth sealing disc 9 surrounds the lower end of the impeller 2, is located at the rigid connection point between the main shaft of the motor 4 and the impeller 2 through the first through hole 521, and is connected to the third step 33 of the sealing disc 3, and is installed on the upper surface of the third step 33.

[0064] The labyrinth seal disc 9 balances the pressure difference before and after sealing by reducing the pressure drop caused by a certain amount of leakage, thus reducing leakage from the gap between the impeller 2 and the seal disc 3 to the rigid connection between the impeller 2 and the main shaft of the motor 4. By adjusting the tooth area and the number of sealing plates of the labyrinth seal disc 9, the pressure difference before and after each sealing plate is adjusted, so that the pressure of the sealing plate along the direction of entering the motor 4 increases, thereby increasing the sealing effect and preventing dangerous gases from entering the motor 4 as much as possible before it takes effect in the elevated space.

[0065] Among them, the labyrinth sealing disc 9 can be a honeycomb structure. When the airflow enters the cavity between the sealing discs from between the teeth, the airflow forms a strong vortex due to the sudden expansion of the flow area, so that the speed is almost completely lost and the kinetic energy is completely converted into the internal energy of the air. This process is repeated tooth by tooth until the entire seal is passed through, and the pressure becomes lower and lower, thus achieving the purpose of sealing.

[0066] For example, motor 4 is installed inside a housing; the housing includes an upper housing 5 and a lower housing 10, such as... Figure 6 As shown.

[0067] The upper housing 5 and the lower housing 10 secure the motor 4. The upper housing 5 is fastened to the first positive pressure chamber 6 via a connecting plate 61. First, the upper housing 5 is connected to the connecting plate 61, extending its length without requiring a housing of the corresponding length, thus reducing manufacturing complexity. Then, the connecting plate 61 connects to the chamber plate of the first positive pressure chamber 6, separating the upper housing 5 from the first positive pressure chamber 6 and reducing vibrations from the first positive pressure chamber 6 to the upper housing 5. Next, the connecting plate 61, in conjunction with a rubber ring, seals the first positive pressure chamber 6, ensuring a positive pressure state inside.

[0068] For example, a cooling device is provided on the upper housing 5 and the lower housing 10, which are used to remove the heat generated by the motor 4 during operation.

[0069] The motor 4, which is fixed in the upper housing 5 and the lower housing 10, is then placed in the first positive pressure chamber 6, which ensures that the entire environment of the motor 4 is under positive pressure.

[0070] For example, see Figure 7 The positive pressure explosion-proof magnetic levitation blower may also include a cabinet 11, an air intake unit 12, and a pressure relief unit 13.

[0071] The cabinet 11 includes a positive pressure chamber and an atmospheric pressure chamber; the positive pressure chamber includes a first positive pressure chamber 6.

[0072] The blower structure includes a volute 1, an impeller 2, and a sealing disc 3; the blower structure is installed inside the atmospheric pressure chamber; the atmospheric pressure chamber is under atmospheric pressure. The aforementioned elevated space is connected to the atmospheric pressure chamber.

[0073] The air intake unit 12 is installed on the outside of the cabinet 11 and is used to provide positive pressure gas to the first positive pressure chamber 6.

[0074] The pressure relief unit 13 is installed on the outside of the cabinet 11 and is used to relieve pressure when the pressure in the first positive pressure chamber 6 is greater than the first pressure threshold.

[0075] It is important to emphasize that the design separates the motor 4 and the blower structure, ensuring that the gas in the blower duct and the gas in the positive pressure cabinet 11 are independent, preventing mutual interference and leakage. Placing the volute 1 and impeller 2 under normal pressure facilitates stable blower operation. The protrusions on the elevated structure 51 support the volute 1, reducing the contact area between the motor 4 and the volute 1, minimizing heat transfer, and contributing to the stability of the volute 1 and impeller 2. Furthermore, the separate placement of the motor 4 and the blower structure prevents the high-speed rotation of the impeller 2 from interfering with the positive pressure environment during blower operation.

[0076] For example, the positive pressure chamber also includes a second positive pressure chamber 14 and a third positive pressure chamber 15; the second positive pressure chamber 14 and the third positive pressure chamber 15 are arranged side by side; the first positive pressure chamber 6, the second positive pressure chamber 14, and the third positive pressure chamber 15 are arranged separately inside the cabinet 11. The first positive pressure chamber 6, the second positive pressure chamber 14, and the third positive pressure chamber 15 are connected and are all in a positive pressure state. The air intake unit 12 is installed on the first cabinet panel 16 on the outside of the cabinet 11. The first cabinet panel 16 and the first cabinet door 17 correspond to the second positive pressure chamber 14. The air intake pipe of the air intake unit 12 enters the second positive pressure chamber 14, providing positive pressure gas to the second positive pressure chamber 14. At the same time, since the first positive pressure chamber 6, the second positive pressure chamber 14, and the third positive pressure chamber 15 are connected, the positive pressure state of the first positive pressure chamber 6 and the third positive pressure chamber 15 can be achieved. Of course, this is just an example, and it is not limited to installing the pipes of the air intake unit 12 on the first positive pressure chamber 6, the second positive pressure chamber 14, and the third positive pressure chamber 15. Considering the rationality and aesthetics of the arrangement of the various devices, it is more reasonable to set the air intake unit 12 on the outside of the first cabinet panel 16 and to install the pipes of the air intake unit 12 on the outside of the second positive pressure chamber 14.

[0077] The pressure relief unit 13 is connected to the air intake unit 12 via a pneumatic device, which is pneumatically controlled by a positive pressure control unit. The pneumatic device can be a number of pneumatic pipes, and the number can be set to 3. Therefore, the pressure relief unit 13 is installed on the outside of the first cabinet plate 16 along with the air intake unit 12.

[0078] For example, the intake unit 12 is provided with a positive pressure control unit; the intake unit 12 and the pressure relief unit 13 are controlled by the positive pressure control unit.

[0079] The first pressure test point 18 detects the pressure inside the cabinet 11. The pneumatic pipeline can be a flexible hose. During the first purging process before the positive pressure explosion-proof magnetic levitation blower is put into use, the dangerous gas inside the cabinet 11 is discharged through the pressure relief unit 13. The pressure relief unit 13 is equipped with a flame arrestor to prevent sparks from being generated when the gas with excessively high temperature passes through the pressure relief unit 13 during equipment operation. The first pressure test point 18 feeds back the pressure signal inside the cabinet 11 to the air intake unit 12. After the set pressure value is reached, the cabinet 11 enters the pressure holding state.

[0080] A first pressure sensor is installed inside the positive pressure chamber. The first pressure sensor is connected to the positive pressure control unit and transmits the pressure signal from inside the positive pressure chamber to the positive pressure control unit. The positive pressure control unit controls the intake unit 12 to supply positive pressure gas to the positive pressure chamber through the intake pipe based on the pressure value measured by the first pressure sensor, and controls the depressurization unit 13. The first pressure sensor is located at the first pressure test point 18. Figure 7As shown, the first pressure sensor at the first pressure measuring point 18 measures the internal pressure of the second positive pressure chamber 14 by passing through the first cabinet panel 16 into the cabinet body 11 via a pipe.

[0081] For example, at least one first pressure sensor is disposed in at least one of the first positive pressure chamber 6, the second positive pressure chamber 14, or the second positive pressure chamber 14. When the positive pressure control unit detects through the first pressure sensor that the pressure inside the first positive pressure chamber 6 is greater than a first pressure threshold, the pressure inside the first positive pressure chamber 6 is too high. At this time, the control unit controls the valve on the pneumatic pipeline between the pressure relief unit 13 and the air intake unit 12 to open, thereby relieving pressure and ensuring that the pressure inside the first positive pressure chamber 6 is within a certain range, while ensuring that the pressure after pressure relief is still greater than the normal pressure state.

[0082] For example, see Figure 8 The positive pressure explosion-proof magnetic levitation blower may also include a PLC control unit 19 and a frequency converter 20.

[0083] The PLC control unit 19 is installed inside the second positive pressure chamber 14. The magnetic levitation blower and frequency converter 20 are controlled by the PLC control unit 19. An operation panel 21 is provided on the first cabinet door 17, such as... Figure 7 As shown, the operation panel 21 is equipped with multiple control buttons, which correspond to the control modules of the PLC control unit 19. Using the operation panel 21, the operator can operate the PLC control unit 19 without opening the first cabinet door 17, thus ensuring the positive pressure state of the positive pressure chamber.

[0084] The frequency converter 20 is installed inside the third positive pressure chamber 15 and is used to provide power voltage to the motor 4 of the magnetic levitation blower.

[0085] The frequency converter 20 is installed inside the third positive pressure chamber 15 and is used to adjust the speed of the motor 4.

[0086] For example, a main cable is installed on the top of the cabinet 11. The main cable, drawn from the power supply, passes through an explosion-proof gland and enters the cabinet 11, where it connects to a circuit breaker. A branch line is then drawn from the circuit breaker to a transformer, and multiple branch lines are drawn from the circuit breaker to connect to power components such as the PLC control unit 19 and the frequency converter 20 for power supply. A transformer is installed on the branch line from the circuit breaker to the PLC control unit 19, and the transformer steps down the industrial voltage to 220V.

[0087] The explosion-proof gland consists of a stainless steel sleeve, a rubber ring, and a locking nut. The cable passes directly through the rubber ring inside the explosion-proof gland and is then sealed by the locking nut. The main cable and the cables connected to the PLC control unit 19, frequency converter 20, etc., are all in a positive pressure environment and can be directly connected to electrical devices.

[0088] For example, a first cable is provided on the positive pressure control unit, which can be located below the positive pressure control unit. The first cable is covered with an explosion-proof flexible conduit. The first cable passes through the through hole of the cabinet 11 and enters the second positive pressure chamber 14 to connect the positive pressure control unit to the PLC control unit 19. The through hole of the cabinet 11 is provided with a rubber ring, and the through hole is sealed by the combination of the explosion-proof flexible conduit, the rubber ring, and a locking nut. A branch circuit is led out through the circuit breaker to the transformer, and then a circuit is led out from the transformer to connect to the PLC. The positive pressure control unit outside the cabinet enters the cabinet through the explosion-proof flexible conduit and connects to the PLC control unit.

[0089] The positive pressure control unit is connected to the PLC control unit 19. The positive pressure control unit sends the control status of the air intake unit 12 and the pressure relief unit 13 to the PLC control unit 19, and the PLC control unit 19 can control the operation process of the positive pressure control unit.

[0090] For example, the positive pressure explosion-proof magnetic levitation blower may also include an alarm unit 22. For example, the alarm unit includes an audible and visual alarm.

[0091] The alarm unit 22 is connected to the PLC control unit 19 via a cable fitted with an explosion-proof flexible tube. The alarm unit 22 is used to issue an alarm when the positive pressure control unit detects that the pressure inside the positive pressure chamber is lower than the second pressure threshold, and to issue an alarm when the air intake unit 12 detects that the pressure inside the positive pressure chamber is higher than the third pressure threshold.

[0092] For example, the motor 4 is equipped with a first cooling device; the first cooling device includes the cooling devices provided on the upper housing 5 and the lower housing 10. The frequency converter 20 is equipped with a second cooling device.

[0093] The first cooling device can be a water-cooled or air-cooled device. When the equipment is running normally, when the cabinet 11 enters the pressure holding state, the internal heat of the cabinet 11 is difficult to dissipate to the outside due to the sealing, which is not conducive to the equipment reaching the CT4 level. Since the motor 4 and the frequency converter 20 are the components with the largest heat generation in the entire equipment, water cooling, which has a better cooling effect than air cooling, can be used for the motor 4 and the frequency converter 20 to reduce the heat generated during the operation of the equipment.

[0094] If water cooling is used to cool the motor 4 and the frequency converter 20, the outer wall of the cabinet 11 is provided with a water inlet and a water outlet connected to the water chiller. The water path at the water inlet and outlet is divided into three: one path goes through the water cooling pipe on the upper section of the motor 4 housing 5, another path goes through the water cooling pipe on the lower section of the motor 4 housing 10, and the last path goes through the frequency converter 20. The cooling water finally returns to the water chiller through the water outlet to form a water circulation.

[0095] When the equipment is in normal operation and the cabinet enters the pressure holding state, the cabinet's sealing makes it difficult for internal heat to dissipate to the outside. Furthermore, since the motor and frequency converter are the components that generate the most heat in the entire equipment, water cooling, which is more effective than air cooling, is used for the motor and frequency converter to reduce the heat generated during equipment operation, which is beneficial for the equipment to achieve CT4 rating.

[0096] For example, the positive pressure chambers are all welded using seamless welding technology to ensure that the positive pressure state of the positive pressure chambers is achieved.

[0097] The invention of this application installs the blower motor inside the positive pressure chamber and rationally arranges the connection relationship between the volute, impeller, sealing plate, and motor. It also sets the upper casing to a fixed height above the upper surface of the first positive pressure chamber, creating an elevated space for the upper casing, sealing plate, and impeller under normal pressure. When the blower is running, if a small amount of dangerous gas enters the intake pipe, most of the gas will be pressurized by the high-speed rotation of the impeller and discharged from the exhaust position. Since the pressure in the chamber where the motor is located is higher than the pressure in the elevated space, a small amount of gas will be discharged through the elevated space, preventing dangerous gas from entering the motor. This prevents external dangerous gas from entering the chamber and contacting the blower motor, further preventing the magnetic levitation blower from exploding and improving the safety of the magnetic levitation blower during operation.

[0098] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A positive pressure explosion-proof magnetic levitation blower, comprising a volute, an impeller, a sealing disc, a motor, an upper casing, and a first positive pressure chamber; The impeller is located in the center of the volute; the impeller is connected to the motor; the upper casing is the upper half of the motor casing; The first positive pressure chamber is located below the impeller; the motor is fixed to the first positive pressure chamber via the upper casing; the upper casing is fixedly higher than the upper surface of the first positive pressure chamber. The sealing disc is connected to the volute to seal the volute and is also connected to the upper housing. The upper housing, the sealing disc, and the impeller form an elevated space, which is under normal pressure. The upper housing includes a raised structure, which includes multiple protrusions; there are gaps between the protrusions; the raised space includes the gaps; the sealing disc is connected to the raised structure. The upper housing includes an upper housing shell; the elevating structure is disposed on the upper surface of the upper housing shell; the protrusions are arranged in a circular array on the upper surface of the upper housing shell; The upper housing has a first through hole, through which the motor's main shaft passes and is rigidly connected to the impeller.

2. The positive pressure explosion-proof magnetic levitation blower according to claim 1, characterized in that, The sealing disc is stepped, including a first step, a second step, a third step, a fourth step, and a first groove; The second step and the fourth step are respectively located on both sides of the first step; the upper surface of the first step is higher than the upper surface of the second step and the upper surface of the fourth step; The third step connects to the second step and is located at the end of the stepped structure, close to the center of the sealing disc; the upper surface of the second step is higher than the upper surface of the third step; The first groove is located on the lower surface of the sealing disc; the protrusion is installed in the first groove, and the height of the protrusion is greater than the depth of the first groove.

3. The positive pressure explosion-proof magnetic levitation blower according to claim 2, characterized in that, The upper surface of the second step is an inclined plane; the inclined plane has a first preset angle θ.

4. The positive pressure explosion-proof magnetic levitation blower according to claim 2, characterized in that, It also includes a maze-sealed disc; The labyrinth sealing disc surrounds the lower end of the impeller and is located at the point where the motor's main shaft passes through the first through hole and is rigidly connected to the impeller, and is in contact with the third step of the sealing disc.

5. The positive pressure explosion-proof magnetic levitation blower according to claim 1, characterized in that, The motor is installed inside the housing; the housing includes an upper housing section and a lower housing section. The upper and lower housing sections fix the motor in place; The upper casing is fastened to the first positive pressure chamber via a connecting plate.

6. The positive pressure explosion-proof magnetic levitation blower according to claim 1, characterized in that, It also includes the cabinet, air intake unit, and pressure relief unit; The cabinet includes a positive pressure chamber and an atmospheric pressure chamber; the positive pressure chamber includes the first positive pressure chamber; The blower structure includes the volute, the impeller, and the sealing disc; the blower structure is installed inside the atmospheric pressure chamber; the atmospheric pressure chamber is under atmospheric pressure. The air intake unit is installed on the outside of the cabinet and is used to provide positive pressure gas to the first positive pressure chamber. The pressure relief unit is installed on the outside of the cabinet and is used to relieve pressure when the pressure inside the first positive pressure chamber is greater than a first pressure threshold.

7. The positive pressure explosion-proof magnetic levitation blower according to claim 6, characterized in that, The positive pressure chamber further includes a second positive pressure chamber and a third positive pressure chamber; the second positive pressure chamber and the third positive pressure chamber are arranged side by side; the first positive pressure chamber, the second positive pressure chamber and the third positive pressure chamber are arranged separately in the cabinet; The first positive pressure chamber, the second positive pressure chamber, and the third positive pressure chamber are connected and are all in a positive pressure state.

8. The positive pressure explosion-proof magnetic levitation blower according to claim 7, characterized in that, It also includes a PLC control unit and a frequency converter; The PLC control unit is installed inside the second positive pressure chamber, and the magnetic levitation blower and the frequency converter are controlled by the PLC control unit. The frequency converter is installed inside the third positive pressure chamber and is used to adjust the speed of the motor.

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