Axially moving magnetic suspension bearingless pump rotor assembly

Abstract

The utility model relates to an axial moving magnetic suspension bearingless pump rotor assembly, which comprises a coil, a fixed plate and a rotor, the coil is positioned at the end part of the rotor, the fixed plate is positioned between the coil and the rotor, the fixed plate is fixedly connected with the end part of the rotor, and the coil drives the fixed plate to move along the axial direction of the rotor through magnetic force. According to the magnetic suspension pump rotor, the coil is additionally arranged in the first groove, and the electrified coil generates a magnetic field, so that the fixed plate is driven to axially move through magnetic force, the rotor which axially deviates is driven to return to a normal position, the rotating speed of the rotor can be further increased, and the problem that the output flow is limited due to the fact that the rotating speed of the magnetic suspension pump rotor is limited is solved; the redundant space of the first groove in an existing magnetic suspension bearingless pump is utilized, the size of the magnetic suspension bearingless pump is not increased, and the magnetic suspension bearingless pump can be matched with the existing magnetic suspension bearingless pump.

Description

Technical Field

[0001] The utility model relates to the technical field of magnetic levitation pump rotors, in particular to an axially movable magnetic levitation bearingless pump rotor assembly. Background Technique

[0002] The magnetic levitation bearingless pump (magnetic levitation pump) belongs to the combination of a centrifugal pump (pump head), a permanent magnet synchronous motor (magnetic levitation motor), and magnetic levitation control, such as the Chinese patent with the publication number CN116526760A. The main operating mechanism is to generate a suspension and rotation magnetic field through the suspension and rotation coils of the motor stator, and then perform non-contact control on the permanent magnet rotor in the centrifugal pump (pump head) through the magnetic field. Specifically, the suspension magnetic field actively controls the radial suspension of the rotor in the X and Y2 degrees of freedom, the rotation magnetic field controls the rotation of the rotor around the Z axis, and finally, the remaining 3 degrees of freedom of passive suspension control are realized by means of the permanent magnet force and the reluctance principle.

[0003] During operation, the fluid pressure at one end of the rotor (inside the pump head) close to the magnetic levitation motor is high, and the fluid pressure at the end far from the magnetic levitation motor is low. The pressure difference causes the rotor to be subjected to an axial force, causing the rotor to move in the direction away from the magnetic levitation motor. As the rotational speed of the rotor increases, the axial force on the rotor increases, and the axial displacement of the rotor increases due to the increased axial force, ultimately causing the rotor to impact the pump head housing, resulting in the magnetic levitation pump being unable to operate normally. Therefore, the rotor of the existing magnetic levitation pump limits the rotational speed to avoid the rotor impacting the pump head housing. Content of the Utility Model

[0004] The utility model aims to solve the above problems and provides a passive air-cooling system for a magnetic levitation motor, which solves the above technical problems.

[0005] An axially movable magnetic levitation bearingless pump rotor assembly includes: a coil, a fixing plate, and a rotor. The coil is located at the end of the rotor, the fixing plate is located between the coil and the rotor, the fixing plate is fixedly connected to the end of the rotor, and the coil drives the fixing plate to move axially along the rotor through magnetic force.

[0006] Further, the fixing plate is made of a ferromagnetic material.

[0007] Further, it further includes a sensor, and the sensor is used to detect the axial position of the rotor and / or the fixing plate.

[0008] Further, the sensor is an eddy current sensor.

[0009] Further, it further includes a control device, a current device, and a power supply. The control device, the current device, the coil, and the sensor are respectively electrically connected to the power supply. The control device is respectively electrically connected to the current device and the sensor. The current device is electrically connected to the coil. The current device is used to control the magnitude of the coil current or the energization time.

[0010] Further, the multiple coils are divided into two groups, and a closed magnetic circuit is generated between the two groups of coils.

[0011] Further, it further includes an iron core, and the iron core passes through the inside of the coil.

[0012] Further, the iron core is a U-shaped iron core. The U-shaped iron core passes through two coils, and the two coils are commonly located in the middle of the U-shaped iron core or are respectively located on different side parts of the U-shaped iron core.

[0013] Further, the iron core is a cylinder, and the cylinder is formed with an annular groove, and the coil is located in the annular groove.

[0014] Further, a first inner hole is formed inside the cylinder. The first inner hole is located inside the annular groove, and a second through hole is formed at the end of the first inner hole.

[0015] The present utility model has the following advantages:

[0016] 1. A coil is installed inside the first groove. The energized coil generates a magnetic field, thereby driving the axial movement of the fixed plate through magnetic force, driving the axially offset rotor back to the normal position, so that the rotor can further increase the rotational speed, and solving the problem of limited output flow caused by the limited rotational speed of the rotor of the magnetic levitation pump.

[0017] 2. The redundant space of the first groove in the existing magnetic levitation bearingless pump is utilized, without increasing the volume of the magnetic levitation bearingless pump, and it can be adapted to the existing magnetic levitation bearingless pump.

[0018] 3. The two groups of coils form a closed magnetic circuit, reducing the magnetic leakage of the coils, thereby reducing the interference to the sensors and other devices inside the magnetic levitation pump, and improving the working stability of the magnetic levitation pump after installing the coils. Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only one embodiment of the present utility model. For those of ordinary skill in the art, without creative efforts, other implementation drawings can also be obtained according to the provided drawings.

[0020] Figure 1: Top view structural schematic diagram of a magnetic levitation bearingless pump;

[0021] Figure 2 : Three-dimensional structural schematic diagram of a magnetic levitation bearingless pump (pump head not shown);

[0022] Figure 3 : Cross-sectional structural schematic diagram of a magnetic levitation bearingless pump (multiple coils);

[0023] Figure 4 : Three-dimensional structural schematic diagram of a coil and a rotor (multiple coils);

[0024] Figure 5 : Cross-sectional structural schematic diagram of a magnetic levitation bearingless pump (one coil);

[0025] Figure 6 : Three-dimensional structural schematic diagram of a coil and a rotor (one coil). Detailed implementation manners

[0026] The present utility model will be further described below in conjunction with the accompanying drawings and examples:

[0027] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.

[0028] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0029] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0030] Such as Figures 1 to 6As shown in the figure, an axially movable magnetic levitation bearingless pump rotor assembly includes: a coil 1, a fixing plate 2, and a rotor 7. The coil 1 is located at the end of the rotor 7. The fixing plate 2 is located between the coil 1 and the rotor 7. The fixing plate 2 is fixedly connected to the end of the rotor 7. The coil 1 drives the fixing plate 2 to move axially along the rotor 7 through magnetic force. The rotor 7 is located inside the pump head 9, and the coil 1 is located in the first groove 60 of the magnetic levitation motor 6, making the coil 1 closer to the fixing plate 2. Thus, when the fixing plate 2 is subjected to the same force, the magnetic field intensity generated by the coil 1 is smaller. A smaller magnetic field intensity is beneficial to reducing the impact on other sensors and devices. It should be noted that the first groove 60 of the magnetic levitation motor 6 is prior art, and the coil 1 utilizes the space in the first groove 60, without the need to additionally increase the volume of the magnetic levitation bearingless pump to accommodate the coil 1.

[0031] Further, the fixing plate 2 is made of ferromagnetic materials, such as iron, cobalt, nickel, and their alloys.

[0032] Further, it further includes a sensor 3. The sensor 3 is used to detect the axial position of the rotor 7 and / or the fixing plate 2. The sensor 3 can adopt distance sensors in the prior art, such as ultrasonic ranging sensors, laser ranging sensors, eddy current sensors, etc.

[0033] Further, the sensor 3 is an eddy current sensor. The sensor 3 is located between the first groove 60 and the fixing plate 2 and is fixedly connected to the housing of the magnetic levitation motor 6 or the housing of the pump head 9.

[0034] Further, it further includes a control device, a current device, and a power supply. The control device, the current device, the coil 1, and the sensor 3 are respectively electrically connected to the power supply. The control device is respectively electrically connected to the current device and the sensor 3. The current device is electrically connected to the coil 1. The current device is used to control the magnitude of the current in the coil 1 or the energization time.

[0035] Further, multiple coils 1 are divided into two groups, and a closed magnetic circuit is generated between the two groups of coils 1. The two groups of coils 1 reduce magnetic leakage. Compared with using only one coil 1, the magnetic leakage is less, and the interference with sensors and devices is smaller.

[0036] Further, it further includes an iron core, and the iron core passes through the inside of the coil 1.

[0037] Further, the iron core is a U-shaped iron core 5. The U-shaped iron core 5 passes through two coils 1, and the two coils 1 are jointly located in the middle of the U-shaped iron core 5 or are respectively located on different side parts of the U-shaped iron core 5.

[0038] Preferably, a threaded hole 601 is formed at the end of the first groove 60, and a third through hole 50 is formed in the middle of the U-shaped iron core 5. A screw passes through the third through hole 50 and is threadedly connected to the threaded hole 601, thereby fixing the U-shaped iron core 5 to the first groove 60.

[0039] Further, the iron core is a cylinder 4, and an annular groove 42 is formed in the cylinder 4. The coil 1 is located in the annular groove 42.

[0040] Further, a first inner hole 40 is formed inside the cylinder 4. The first inner hole 40 is located inside the annular groove 42, and a second through hole 41 is formed at the end of the first inner hole 40.

[0041] Preferably, a threaded hole 601 is formed at the end of the first groove 60. The second through hole 41 communicates with the first inner hole 40. A screw passes through the second through hole 41 and is threadedly connected to the threaded hole 601, thereby fixing the cylinder 4 to the first groove 60.

[0042] During installation, the iron core with the coil 1 fixed is inserted into the first groove 60 and fixedly connected to the first groove 60. The fixing plate 2 is fixed to the rotor 7, and the sensor 3 is fixed to the magnetic levitation motor 6 or the pump head. It should be noted that the above fixing methods adopt existing fixing methods such as bonding and threaded connection.

[0043] During operation, the rotor 7 rotates. Under the action of the pressure difference, the rotor 7 rotates and moves axially in a direction away from the magnetic levitation motor 6. The sensor 3 senses the axial displacement of the position of the fixing plate 2 or the rotor 7. The sensor 3 transmits the signal to the control device. The control device controls the current device, and the current device changes the current magnitude of the coil 1 to change the magnetic field intensity, or changes the energization time of the coil 1 to change the time of the magnetic field generated by the coil 1. The magnetic force of the coil 1 attracts the fixing plate 2 and drives the rotor 7 to move axially in a direction close to the magnetic levitation motor 6, thereby preventing the axial displacement of the rotor 7 from being too large.

[0044] When the axial position of the rotor 7 is too close to the magnetic levitation motor 6, the coil 1 is powered off or the power-off time is increased. Under the pressure difference of the fluid, the rotor 7 will automatically move in a direction away from the magnetic levitation motor 6.

[0045] Preferably, the control device is a single-chip microcomputer, and the current device is a MOS transistor. The MOS transistor continuously switches, and the MOS transistor controls the time when the coil 1 has magnetic force by changing the duty cycle of the coil 1.

[0046] It should be noted that the internal components outside the rotor 7 of the pump head 9 and the internal components of the magnetic levitation motor 6 are not shown in the figure and are all prior arts. Among them, the pump head 9 is inserted into the end cover 61 and fixed.

[0047] The above has described the present utility model by way of example, but the present utility model is not limited to the above specific embodiments. Any modification or variation based on the present utility model falls within the scope of protection required by the present utility model.

Claims

1. An axially movable magnetic suspension bearingless pump rotor assembly, characterized in that: include: A coil (1), a fixing plate (2) and a rotor (7), wherein the coil (1) is located at an end of the rotor (7), the fixing plate (2) is located between the coil (1) and the rotor (7), the fixing plate (2) is fixedly connected to the end of the rotor (7), and the coil (1) drives the fixing plate (2) to move axially along the rotor (7) through magnetic force.

2. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 1 is characterized in that: The fixing plate (2) is made of ferromagnetic material.

3. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 1 is characterized in that: It also comprises a sensor (3), wherein the sensor (3) is used to detect the axial position of the rotor (7) and / or the fixing plate (2).

4. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 3 is characterized in that: The sensor (3) is an eddy current sensor.

5. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 3 is characterized in that: It also comprises a control device, a current device and a power supply, wherein the control device, the current device, the coil (1) and the sensor (3) are respectively electrically connected to the power supply, the control device is respectively electrically connected to the current device and the sensor (3), the current device is electrically connected to the coil (1), and the current device is used to control the magnitude of the current of the coil (1) or the power-on time.

6. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 1 is characterized in that: The plurality of coils (1) are divided into two groups, and a closed magnetic circuit is generated between the two groups of coils (1).

7. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 1 is characterized in that: It also includes an iron core, which passes through the interior of the coil (1).

8. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 7 is characterized in that: The iron core is a U-shaped iron core (5), the U-shaped iron core (5) passes through two coils (1), and the two coils (1) are located together in the middle of the U-shaped iron core (5) or respectively on different sides of the U-shaped iron core (5).

9. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 7 is characterized in that: The iron core is a cylinder (4), the cylinder (4) is formed with an annular groove (42), and the coil (1) is located in the annular groove (42).

10. The axially movable magnetic suspension bearingless pump rotor assembly according to claim 9, characterized in that: A first inner hole (40) is formed inside the cylinder (4), the first inner hole (40) is located inside the annular groove (42), and a second through hole (41) is formed at the end of the first inner hole (40).

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