阅读说明：本技术 一种磁悬浮鼓风机的散热通道 (Heat dissipation channel of magnetic suspension air blower ) 是由 袁军 钟仁志 于 2021-10-13 设计创作，主要内容包括：本发明涉及磁悬浮鼓风机领域,尤其涉及一种磁悬浮鼓风机的散热通道。该鼓风机包括电机筒、前轴承座、后轴承座和电机轴壳；电机轴固定设置有电机转子；电机转子包括硅钢片、磁钢、前转子磁钢座和后转子磁钢座；后轴承座设置有轴向贯穿的多个第一通道,后转子磁钢座设置有第二通道和第三通道；电机轴设置有轴向贯穿的第四通道,前转子磁钢座设置有第五通道；硅钢片设置有多个轴向贯穿的第六通道,电机筒设置有多个径向贯穿的第七通道；第一通道、第二通道、第四通道、第五通道、第六通道、电机筒内部间隙和第七通道依次连通形成散热通道。该散热通道将单层的冷却通道转化为多层弯折的冷却通道,进一步提高了对转子部分冷却效果。(The utility model relates to the field of magnetic suspension air blowers, in particular to a heat dissipation channel of a magnetic suspension air blower. The blower comprises a motor barrel, a front bearing seat, a rear bearing seat and a motor shaft shell; a motor rotor is fixedly arranged on the motor shaft; the motor rotor comprises a silicon steel sheet, magnetic steel, a front rotor magnetic steel seat and a rear rotor magnetic steel seat; the rear bearing seat is provided with a plurality of first channels which axially penetrate through the rear bearing seat, and the rear rotor magnetic steel seat is provided with a second channel and a third channel; the motor shaft is provided with a fourth channel which axially penetrates through the motor shaft, and the front rotor magnetic steel seat is provided with a fifth channel; the silicon steel sheet is provided with a plurality of axially-through sixth channels, and the motor cylinder is provided with a plurality of radially-through seventh channels; the first channel, the second channel, the fourth channel, the fifth channel, the sixth channel, the motor cylinder inner gap and the seventh channel are communicated in sequence to form a heat dissipation channel. The heat dissipation channel converts a single-layer cooling channel into a multi-layer bent cooling channel, and further improves the cooling effect of the rotor part.)

1. A heat dissipation channel of a magnetic suspension blower is characterized in that the blower comprises a motor barrel (1), a front bearing seat (2), a rear bearing seat (3), a motor shaft (4), an impeller (5) and a volute (6); a motor stator (11) is fixedly embedded in the inner wall of the motor barrel (1), and a motor rotor (41) corresponding to the position of the motor stator (11) is fixedly arranged on the motor shaft (4); the motor rotor (41) comprises a silicon steel sheet (46), a magnetic steel (47), a front rotor magnetic steel seat (48) and a rear rotor magnetic steel seat (49); the plurality of silicon steel sheets (46) are fixedly sleeved on the outer wall of the motor shaft (4) and are axially aligned and stacked, and the front rotor magnetic steel seat (48) and the rear rotor magnetic steel seat (49) are fixedly sleeved on the outer wall of the motor shaft (4) and are respectively positioned at the two axial ends of the stacked silicon steel sheets (46); the silicon steel sheet (46) is provided with magnetic steel holes, and a plurality of magnetic steels (47) are fixedly embedded in the magnetic steel holes; the rear bearing seat (3) is provided with a plurality of first channels (81) which axially penetrate through, and the rear rotor magnetic steel seat (49) is provided with a second channel (82) and a third channel (83); the motor shaft (4) is provided with a fourth channel (84) which axially penetrates through, and the front rotor magnetic steel seat (48) is provided with a fifth channel (85); the silicon steel sheet (46) is provided with a plurality of axially-through sixth channels (86), and the motor barrel (1) is provided with a plurality of radially-through seventh channels (87); the first channel (81), the second channel (82), the fourth channel (84), the fifth channel (85), the sixth channel (86), the inner gap of the motor cylinder (1) and the seventh channel (87) are communicated in sequence to form a heat dissipation channel.

2. The heat dissipation channel of the magnetic suspension blower as claimed in claim 1, characterized in that the magnetic suspension blower is further provided with a bearing fixing block (7); the motor shaft (4) is provided with a rotor bearing hole (42) along the axial direction, and the bearing fixing block (7) is fixed on the rear bearing block (3) and is positioned in the rotor bearing hole (42); the inner wall of the rotor bearing hole (42) is fixedly provided with radial rotor magnetic steel (43), the bearing fixing block (7) is fixedly provided with radial stator magnetic steel (71), the radial stator magnetic steel (71) corresponds to the radial rotor magnetic steel (43) in position, and the magnetic poles of the opposite surfaces of the radial stator magnetic steel and the radial rotor magnetic steel are opposite.

3. The heat dissipation channel of a magnetic levitation blower according to claim 2, characterized in that the motor shaft (4) is further provided with a rotor channel (40), and the front bearing block (2) is provided with a radially penetrating bearing block channel (26); the first channel (81), the rotor bearing hole (42), the rotor channel (40) and the bearing seat channel (26) are communicated in sequence to form a second heat dissipation channel.

4. The heat dissipation channel of a magnetic levitation blower according to claim 1, characterized in that the rear rotor magnet steel holder (49) is further provided with an eighth channel (88); the first channel (81), the eighth channel (88), the sixth channel (86) and the seventh channel (87) are communicated in sequence to form a third heat dissipation channel.

5. The heat dissipation channel of the magnetic suspension blower as claimed in claim 1, wherein the motor shaft (4) is fixedly provided with a front rotor magnetic steel (44) and a rear rotor magnetic steel (45) at the front and rear axial sides respectively, and the front bearing seat (2) and the rear bearing seat (3) are fixedly provided with a front stator magnetic steel (21) and a rear stator magnetic steel (31) respectively; the front stator magnetic steel (21) and the front rotor magnetic steel (44) are corresponding in position and opposite in magnetic pole on the opposite surfaces, and the rear stator magnetic steel (31) and the rear rotor magnetic steel (45) are corresponding in position and opposite in magnetic pole on the opposite surfaces.

6. The heat dissipation channel of the magnetic suspension blower as claimed in claim 5, wherein a front stator magnetic steel seat (22) is fixedly arranged on the inner side surface of the front bearing seat (2), a front magnetic steel groove (23) is arranged on the inner side of the front stator magnetic steel seat (22), and the front stator magnetic steel (21) is fixedly embedded in the front magnetic steel groove (23); a rear stator magnetic steel seat (32) is fixedly arranged on the inner side surface of the rear bearing seat (3), a rear magnetic steel groove (33) is arranged on the inner side of the rear stator magnetic steel seat (32), and the rear stator magnetic steel (31) is fixedly embedded in the rear magnetic steel groove (33).

7. The heat dissipation channel of the magnetic suspension blower as claimed in claim 6, wherein the outer side surfaces of the front stator magnetic steel seat (22) and the rear stator magnetic steel seat (32) are provided with threaded holes (24), and the front bearing seat (2) and the rear bearing seat (3) are provided with screw holes (34) which axially penetrate through; the magnetic suspension air blower is also provided with locking screws and locking nuts, and the locking screws respectively penetrate through screw holes (34) of the front bearing seat (2) and the rear bearing seat (3) and are respectively screwed into screw holes (24) of the front stator magnetic steel seat (22) and the rear stator magnetic steel seat (32); the plurality of locking nuts are screwed with the locking screws respectively, and the inner surfaces of the plurality of locking nuts are attached to the outer side surfaces of the front bearing seat (2) and the rear bearing seat (3) respectively.

8. The heat dissipation channel of the magnetic suspension blower as claimed in claim 1, characterized in that the outer wall of the motor cylinder (1) is provided with heat dissipation ribs (12), and the heat dissipation ribs (12) are used for dissipating heat of the motor cylinder (1).

9. The heat dissipation channel of the magnetic suspension blower as claimed in claim 1, wherein the inlet end of the impeller (5) is provided with a fairing (51), and the fairing (51) is used for rectifying the gas at the inlet end of the volute (6) to improve the inlet efficiency.

10. The heat dissipation channel of the magnetic suspension blower as claimed in claim 1, characterized in that the impeller (5) is provided with a convex reinforcing rib (52) on the back side, and the front bearing seat (2) is provided with a labyrinth seal (25); the radial outer surface of the reinforcing rib (52) and the labyrinth seal (25) form a labyrinth structure for reducing gas discharge at the gas outlet end of the impeller (5).

Technical Field

The utility model relates to the field of magnetic suspension air blowers, in particular to a heat dissipation channel of a magnetic suspension air blower.

Background

The magnetic suspension blower is one kind of turbine equipment with magnetic suspension bearing. The main structure is that the blower impeller is directly installed on the extension end of the firing shaft, and the rotor is vertically suspended on the active magnetic bearing, so as to realize the single-machine high-speed centrifugal blower which is directly driven by the high-speed motor and is regulated by the frequency converter. The fan adopts an integrated design, has the technical characteristics of energy conservation, high efficiency, high cooling efficiency, low noise and the like, and is widely applied to factories at present.

The Chinese utility model patent application (publication No. CN209398592U, published: 20140604) discloses a magnetic suspension blower, which comprises a motor, a cooling system and a load pipeline; the cooling system is arranged on a motor of the blower, the load pipeline is arranged at the outlet of the blower and is communicated with the air outlet of the cooling system; the magnetic suspension blower provided by the utility model has the advantages that the structure of the magnetic suspension blower is optimized, the energy is fully utilized, the gas generated by the cooling system is introduced into the load pipeline and is integrated with the air flow discharged by the blower, and the gas is completely converted into the compressed gas required by the load and utilized, so that the utilization rate of energy consumption is improved, and the energy conservation optimization is effectively carried out.

The prior art has the following defects: when a rotor system is cooled by a traditional centrifugal blower, a single-layer channel penetrating along the axial direction is generally arranged on stacked silicon steel sheets, and then external cooling gas is introduced into the channel to cool the rotor system; in the mode, the length of the cooling channel which penetrates through the single layer along the axial direction is short, the radial thickness of the silicon steel sheet is large when the diameter of the silicon steel sheet is large, only the part of the silicon steel sheet which is radially close to the single-layer cooling channel can be cooled, and the part of the silicon steel sheet which is radially far from the single-layer cooling channel is not easy to transfer the heat of the silicon steel sheet to the single-layer cooling channel; thereby causing the poor cooling effect of silicon steel sheet, also increasing the temperature of air-blower, be unfavorable for protecting air-blower internals.

Disclosure of Invention

The purpose of the utility model is: aiming at the problems, a fourth channel and a sixth channel which are axially penetrated are respectively arranged on a motor shaft and a silicon steel sheet, and the two axial channels are communicated through a fifth channel, so that a single-layer cooling channel is converted into a multi-layer bent cooling channel, and the length of the cooling channel is increased; meanwhile, the rotor part with large radial thickness can be divided into a plurality of layers of rotor parts with small radial thickness by the channel for cooling, so that the cooling effect of the rotor part is further improved.

In order to achieve the purpose, the utility model adopts the following technical scheme:

a heat dissipation channel of a magnetic suspension blower comprises a motor barrel, a front bearing seat, a rear bearing seat, a motor shaft, an impeller and a volute; a motor stator is fixedly embedded in the inner wall of the motor barrel, and a motor rotor corresponding to the motor stator is fixedly arranged on a motor shaft; the motor rotor comprises a silicon steel sheet, magnetic steel, a front rotor magnetic steel seat and a rear rotor magnetic steel seat; the front rotor magnetic steel seat and the rear rotor magnetic steel seat are fixedly sleeved on the outer wall of the motor shaft and are respectively positioned at the two axial ends of the stacked silicon steel sheets; the silicon steel sheet is provided with a magnetic steel hole, and a plurality of magnetic steels are fixedly embedded in the magnetic steel hole; the rear bearing seat is provided with a plurality of first channels which axially penetrate through the rear bearing seat, and the rear rotor magnetic steel seat is provided with a second channel and a third channel; the motor shaft is provided with a fourth channel which axially penetrates through the motor shaft, and the front rotor magnetic steel seat is provided with a fifth channel; the silicon steel sheet is provided with a plurality of axially-through sixth channels, and the motor cylinder is provided with a plurality of radially-through seventh channels; the first channel, the second channel, the fourth channel, the fifth channel, the sixth channel, the motor cylinder inner gap and the seventh channel are communicated in sequence to form a heat dissipation channel.

Preferably, the magnetic suspension blower is also provided with a bearing fixing block; the motor shaft is provided with a rotor bearing hole along the axial direction, and the bearing fixing block is fixed on the rear bearing seat and is positioned in the rotor bearing hole; the inner wall of the rotor bearing hole is fixedly provided with radial rotor magnetic steel, the bearing fixing block is fixedly provided with radial stator magnetic steel, the radial stator magnetic steel corresponds to the radial rotor magnetic steel in position, and the magnetic poles of the opposite surfaces of the radial stator magnetic steel and the radial rotor magnetic steel are opposite.

Preferably, the motor shaft is also provided with a rotor channel, and the front bearing seat is provided with a bearing seat channel which penetrates through the front bearing seat in the radial direction; the first channel, the rotor bearing hole, the rotor channel and the bearing seat channel are communicated in sequence to form a second heat dissipation channel.

Preferably, the rear rotor magnetic steel seat is also provided with an eighth channel; the first channel, the eighth channel, the sixth channel and the seventh channel are communicated in sequence to form a third heat dissipation channel.

Preferably, the front rotor magnetic steel and the rear rotor magnetic steel are respectively and fixedly arranged on the front axial direction and the rear axial direction of the motor shaft, and the front stator magnetic steel and the rear stator magnetic steel are respectively and fixedly arranged on the front bearing seat and the rear bearing seat; the front stator magnetic steel and the front rotor magnetic steel are corresponding in position and opposite in magnetic pole on the opposite surfaces, and the rear stator magnetic steel and the rear rotor magnetic steel are corresponding in position and opposite in magnetic pole on the opposite surfaces.

Preferably, a front stator magnetic steel seat is fixedly arranged on the inner side surface of the front bearing seat, a front magnetic steel groove is formed in the inner side of the front stator magnetic steel seat, and the front stator magnetic steel is fixedly embedded in the front magnetic steel groove; the inner side surface of the rear bearing seat is fixedly provided with a rear stator magnetic steel seat, the inner side of the rear stator magnetic steel seat is provided with a rear magnetic steel groove, and the rear stator magnetic steel is fixedly embedded in the rear magnetic steel groove.

Preferably, the outer side surfaces of the front stator magnetic steel seat and the rear stator magnetic steel seat are provided with threaded holes, and the front bearing seat and the rear bearing seat are provided with screw holes which axially penetrate through the front bearing seat and the rear bearing seat; the magnetic suspension air blower is also provided with locking screws and locking nuts, and the locking screws respectively penetrate through the screw holes of the front bearing seat and the rear bearing seat and are respectively screwed into the screw holes of the front stator magnetic steel seat and the rear stator magnetic steel seat; the plurality of locking nuts are screwed with the locking screws respectively, and the inner surfaces of the plurality of locking nuts are attached to the outer side surfaces of the front bearing seat and the rear bearing seat respectively.

Preferably, the outer wall of the motor cylinder is provided with a heat dissipation rib, and the heat dissipation rib is used for dissipating heat of the motor cylinder.

Preferably, the air inlet end of the impeller is provided with a fairing, and the fairing is used for rectifying the gas at the air inlet end of the volute so as to improve the air inlet efficiency.

Preferably, the back of the impeller is provided with a convex reinforcing rib, and the front bearing seat is provided with a labyrinth seal; the radial outer surface of the reinforcing rib and the labyrinth seal form a labyrinth structure for reducing gas discharge at the gas outlet end of the impeller.

The heat dissipation channel of the magnetic suspension blower adopting the technical scheme has the advantages that:

when the cooling device works, the motor stator is electrified to drive the motor rotor to rotate so as to drive the motor shaft to rotate, and external cooling air enters the blower along the heat dissipation channel to cool the blower and then is discharged along the seventh channel to finish the cooling process of the blower; in the mode, the fourth channel and the sixth channel are axially distributed cooling channels and are communicated through a fifth channel; in the cooling mode, the multi-layer bent cooling channels are adopted for cooling in the radial direction, so that the length of the cooling channels is increased; and when the rotor part is bigger in radial thickness, the multilayer cooling channel can cool the rotor part with bigger radial thickness into the part with smaller radial thickness of the multilayer, thereby further improving the cooling effect on the rotor part.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural diagram of a magnetic suspension blower.

Fig. 3 is a schematic structural view of the front bearing seat.

Fig. 4 is a schematic structural view of the rear bearing seat.

Fig. 5 is a schematic structural view of a blower rotor system.

Fig. 6 and 7 are schematic structural diagrams of the motor rotor.

Fig. 8 and 9 are schematic structural views of the motor cylinder.

Fig. 10 is a schematic structural view of an impeller.

Fig. 11 and 12 are schematic structural views of a motor shaft.

Fig. 13 is a schematic structural diagram of a radial rotor magnetic steel field.

Fig. 14-16 are schematic structural views of the front rotor magnetic steel seat.

Fig. 17-19 are schematic structural views of the rear rotor magnetic steel seat.

Fig. 20 is a schematic structural view of a bearing fixing block.

Fig. 21 is a schematic diagram of the structure of a radial stator magnetic steel field.

Detailed Description

The following describes in detail embodiments of the present invention with reference to the drawings.

Example 1

The heat dissipation channel of a magnetic suspension blower is shown in fig. 1, 2 and 5-7, and the blower comprises a motor barrel 1, a front bearing seat 2, a rear bearing seat 3, a motor shaft 4, an impeller 5 and a volute 6; a motor stator 11 is fixedly embedded in the inner wall of the motor barrel 1, and a motor rotor 41 corresponding to the position of the motor stator 11 is fixedly arranged on the motor shaft 4; the motor rotor 41 comprises a silicon steel sheet 46, a magnetic steel 47, a front rotor magnetic steel seat 48 and a rear rotor magnetic steel seat 49; the plurality of silicon steel sheets 46 are fixedly sleeved on the outer wall of the motor shaft 4 and are axially aligned and stacked, and the front rotor magnetic steel seat 48 and the rear rotor magnetic steel seat 49 are fixedly sleeved on the outer wall of the motor shaft 4 and are respectively positioned at the two axial ends of the stacked silicon steel sheets 46; the silicon steel sheet 46 is provided with magnetic steel holes, and a plurality of magnetic steels 47 are fixedly embedded in the magnetic steel holes; the rear bearing block 3 is provided with a plurality of first channels 81 which axially penetrate through, and the rear rotor magnetic steel block 49 is provided with a second channel 82 and a third channel 83; the motor shaft 4 is provided with a fourth channel 84 which axially penetrates through, and the front rotor magnetic steel seat 48 is provided with a fifth channel 85; the silicon steel sheets 46 are provided with a plurality of sixth passages 86 which axially penetrate through, and the motor cylinder 1 is provided with a plurality of seventh passages 87 which radially penetrate through; the first channel 81, the second channel 82, the fourth channel 84, the fifth channel 85, the sixth channel 86, the inner gap of the motor cylinder 1 and the seventh channel 87 are communicated in sequence to form a heat dissipation channel. When the cooling device works, the motor stator 11 is electrified to drive the motor rotor 41 to rotate so as to drive the motor shaft 4 to rotate, and external cooling air enters the blower along the heat dissipation channel to cool the blower and then is discharged along the seventh channel 87 to finish the cooling process of the blower; in this way, the fourth passage 84 and the sixth passage 86 are axially distributed cooling passages, and are communicated with each other through the fifth passage 85; in the cooling mode, the multi-layer bent cooling channels are adopted for cooling in the radial direction, so that the length of the cooling channels is increased; and when the rotor part is bigger in radial thickness, the multilayer cooling channel can cool the rotor part with bigger radial thickness into the part with smaller radial thickness of the multilayer, thereby further improving the cooling effect on the rotor part.

The magnetic suspension air blower is also provided with a bearing fixing block 7; the motor shaft 4 is provided with a rotor bearing hole 42 along the axial direction, and the bearing fixing block 7 is fixed on the rear bearing block 3 and is positioned in the rotor bearing hole 42; the inner wall of the rotor bearing hole 42 is fixedly provided with radial rotor magnetic steel 43, the bearing fixing block 7 is fixedly provided with radial stator magnetic steel 71, the radial stator magnetic steel 71 corresponds to the radial rotor magnetic steel 43 in position, and the magnetic poles of the opposite surfaces of the radial stator magnetic steel 71 and the radial rotor magnetic steel 43 are opposite.

The motor shaft 4 is also provided with a rotor channel 40, and the front bearing seat 2 is provided with a bearing seat channel 26 which penetrates through the front bearing seat in the radial direction; the first channel 81, the rotor bearing hole 42, the rotor channel 40 and the bearing seat channel 26 are sequentially communicated to form a second heat dissipation channel.

The rear rotor magnetic steel seat 49 is also provided with an eighth channel 88; the first channel 81, the eighth channel 88, the sixth channel 86 and the seventh channel 87 are communicated in sequence to form a third heat dissipation channel.

The front rotor magnetic steel 44 and the rear rotor magnetic steel 45 are respectively and fixedly arranged on the two sides of the motor shaft 4 in the front-rear axial direction, and the front stator magnetic steel 21 and the rear stator magnetic steel 31 are respectively and fixedly arranged on the front bearing seat 2 and the rear bearing seat 3; the front stator magnetic steel 21 and the front rotor magnetic steel 44 are corresponding in position and opposite in magnetic pole on the opposite surfaces, and the rear stator magnetic steel 31 and the rear rotor magnetic steel 45 are corresponding in position and opposite in magnetic pole on the opposite surfaces. When the motor works, the motor stator 11 is electrified to drive the motor rotor 41 to rotate so as to drive the motor shaft 4 to rotate; the front stator magnetic steel 21 and the rear stator magnetic steel 31 respectively control the positions of the front rotor magnetic steel 44 and the rear rotor magnetic steel 45 through magnetic force so as to control the axial position of the motor shaft 4, and the radial stator magnetic steel 71 controls the position of the radial rotor magnetic steel 43 so as to control the radial position of the motor shaft 4; meanwhile, the motor shaft 4 rotates to drive the impeller 5 to rotate, so that external air is compressed, and the working process of the magnetic suspension blower is completed. In this way, the passive magnetic bearing is divided into three pairs of six circular ring magnetic steels, wherein the action surfaces of the two magnetic steels of each group of bearings are all homopolar, and repulsion is generated to restrain the displacement of the rotor with six degrees of freedom. The supporting surface between the radial stator magnetic steel 71 and the radial rotor magnetic steel 43 almost supports the inside of the whole rotor shaft system, so that great supporting force is provided, and the rigidity of the bearing is greatly superior to that of other types of bearings. In addition, the mode adopts the form of a passive magnetic suspension bearing in the axial direction and the radial direction, the motor shaft is directly controlled by the magnetic force of the magnetic steel, lubricating oil lubrication is not needed, and the maintenance steps are reduced; meanwhile, the passive magnetic suspension bearing does not need a sensor, so that the price of a magnetic bearing is reduced, the structure of the air blower is simplified, and the stability of the system is improved.

As shown in fig. 3 and 4, a front stator magnetic steel seat 22 is fixedly arranged on the inner side surface of the front bearing seat 2, a front magnetic steel groove 23 is arranged on the inner side of the front stator magnetic steel seat 22, and the front stator magnetic steel 21 is fixedly embedded in the front magnetic steel groove 23; the inner side surface of the rear bearing seat 3 is fixedly provided with a rear stator magnetic steel seat 32, the inner side of the rear stator magnetic steel seat 32 is provided with a rear magnetic steel groove 33, and the rear stator magnetic steel 31 is fixedly embedded in the rear magnetic steel groove 33.

The outer side surfaces of the front stator magnetic steel seat 22 and the rear stator magnetic steel seat 32 are provided with threaded holes 24, and the front bearing seat 2 and the rear bearing seat 3 are provided with screw holes 34 which axially penetrate through; the magnetic suspension air blower is also provided with locking screws and locking nuts, and the locking screws respectively penetrate through screw holes 34 of the front bearing seat 2 and the rear bearing seat 3 and are respectively screwed into threaded holes 24 of the front stator magnetic steel seat 22 and the rear stator magnetic steel seat 32; the plurality of locking nuts are screwed with the locking screws respectively, and the inner surfaces of the plurality of locking nuts are attached to the outer side surfaces of the front bearing seat 2 and the rear bearing seat 3 respectively. When the actual load of the motor shaft 4 changes, the axial position of the locking screw is adjusted to respectively drive the front stator magnetic steel seat 22 and the rear stator magnetic steel seat 32 to axially move to the corresponding positions, and then the locking screw is locked by using a locking nut; thereby adjusting the distance between the front stator magnetic steel 21 and the front rotor magnetic steel 44 and the distance between the rear stator magnetic steel 31 and the rear rotor magnetic steel 45 to change the magnitude of the repulsive force between the two; so that the repulsive force between the front stator magnetic steel 21 and the front rotor magnetic steel 44 and between the rear stator magnetic steel 31 and the rear rotor magnetic steel 45 satisfies the actual load of the motor shaft 4.

As shown in fig. 8 and 9, the outer wall of the motor cylinder 1 is provided with heat dissipation ribs 12, and the heat dissipation ribs 12 are used for dissipating heat from the motor cylinder 1.

The inlet end of the impeller 5 is provided with a fairing 51, and the fairing 51 is used for rectifying the gas at the inlet end of the volute 6, so that the inlet efficiency is improved.

The back of the impeller 5 is provided with a convex reinforcing rib 52, and the front bearing seat 2 is provided with a labyrinth seal 25; the radially outer surface of the rib 52 forms a labyrinth structure with the labyrinth seal 25 for reducing gas discharge at the gas outlet end of the impeller 5.