CN113339286A

CN113339286A - Axial flow fan adopting magnetic suspension outer rotor

Info

Publication number: CN113339286A
Application number: CN202110717661.6A
Authority: CN
Inventors: 钟仁志; 袁军
Original assignee: Xinlei Compressor Co Ltd
Current assignee: Xinlei Compressor Co Ltd
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2021-09-03

Abstract

The invention relates to the field of axial flow fans, in particular to an axial flow fan adopting a magnetic suspension outer rotor. The device comprises a fan barrel, a motor shaft, a rotor seat, an axial flow fan, a motor stator, a motor rotor, a magnetic bearing device, an inlet guide vane and an outlet guide vane; the rotor base is internally provided with a rotor base inner hole, and the magnetic bearing device comprises a radial magnetic bearing and an axial magnetic bearing; the radial magnetic bearing comprises a radial bearing stator and a radial bearing rotor which are oppositely arranged, and the axial magnetic bearing comprises a thrust disc and a plurality of axial bearing stators which are positioned at the two axial ends of the thrust disc; the axial flow fan is fixedly arranged on the outer wall of the rotor seat; the inlet guide vane and the outlet guide vane are fixed on the fan barrel and are respectively positioned at two axial ends of the axial flow fan. The axial flow fan is internally provided with a radial magnetic bearing and an axial magnetic bearing, so that the rotating speed of the axial flow fan is improved; and then reduce the volume of rotor seat and axial fan's blade volume in the axial fan, reduce the cost of equipment, reduce the space that needs to occupy when installing.

Description

Axial flow fan adopting magnetic suspension outer rotor

Technical Field

The invention relates to the field of axial flow fans, in particular to an axial flow fan adopting a magnetic suspension outer rotor.

Background

The axial flow fan has a very wide application, namely, the axial flow fan is an air flow in the same direction as the axis of the fan blade, such as an electric fan, and an air conditioner outer fan is an axial flow type running fan, so the axial flow fan is called as an axial flow type, because air flows in parallel to the fan axis, the axial flow fan is usually used in the occasions with higher flow requirement and lower pressure requirement, the axial flow fan is fixed in position and moves the air, the axial flow fan mainly comprises a fan impeller and a casing, the structure is simple, but the data requirement is very high. The general axial flow fan can be used for ventilation in general factories, warehouses, offices, houses and other places, and can also be used for air coolers (air coolers), evaporators, condensers and the like.

Chinese Utility model patent application (publication No. CN212959277U, published: 20210413) discloses an energy-saving axial flow fan, comprising an energy-saving axial flow fan shell and an axial flow fan installed in the energy-saving axial flow fan shell, wherein a port of the energy-saving axial flow fan shell is provided with a net frame and a protective frame, a dust screen is arranged in the net frame, an inner extension ring is integrally formed on the inner wall of the energy-saving axial flow fan shell at a position close to the net frame, a lug is integrally formed on the outer part of the protective frame, and through the net frame arranged between the energy-saving axial flow fan shell and an inner groove, the dust screen in the net frame can effectively isolate the external dust to prevent the dust from entering the energy-saving axial flow fan shell, and meanwhile, through a handle rod formed on the outer wall of the energy-saving inner groove fan shell and anti-slip veins distributed on the surface of the energy-saving axial flow fan shell, personnel can conveniently lift and transport the fan normally, the efficient and stable utilization operation of the energy-saving axial flow fan is ensured.

The prior art has the following defects: the ball bearing is adopted to radially support and axially limit the motor shaft, and the rotation speed of the motor shaft is low due to friction generated by mechanical contact when the ball bearing rotates; compared with a motor shaft with high rotating speed, the motor shaft with lower rotating speed has low rotating speed and large volume; meanwhile, compared with an axial flow fan rotating at a high speed, the axial flow fan rotating at a low speed needs larger blades when the same pressure and flow are generated; and then the whole axial flow fan is large in size, so that the cost of the equipment is increased, and the occupied space is needed during installation.

Disclosure of Invention

The purpose of the invention is: aiming at the problems, the radial magnetic bearing and the axial magnetic bearing are arranged in the axial flow fan, so that the rotating speed of the axial flow fan is improved; and then reduce the volume of the rotor seat and blade volume of the axial fan in the axial fan, reduce the cost of the apparatus, reduce the axial fan which needs the space that takes up when installing one kind and adopts the magnetic suspension outer rotor.

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

an axial flow fan adopting a magnetic suspension outer rotor comprises a fan barrel, a motor shaft, a rotor seat, an axial flow fan, a motor stator, a motor rotor, a magnetic bearing device, an inlet guide vane and an outlet guide vane; the motor shaft is fixed on the fan barrel, a rotor seat inner hole is arranged in the rotor seat, and the magnetic bearing device comprises a radial magnetic bearing and an axial magnetic bearing; the radial magnetic bearing comprises a radial bearing stator and a radial bearing rotor which are oppositely arranged, and the axial magnetic bearing comprises a thrust disc and a plurality of axial bearing stators which are positioned at the two axial ends of the thrust disc; the motor stator, the radial bearing stator and the axial bearing stator are fixedly sleeved on the motor shaft, and the motor rotor, the radial bearing rotor and the thrust disc are fixedly embedded in the inner hole of the rotor seat; the axial flow fan is fixedly arranged on the outer wall of the rotor seat; the inlet guide vane and the outlet guide vane are fixed on the fan barrel and are respectively positioned at two axial ends of the axial flow fan.

Preferably, the plurality of radial magnetic bearings are respectively located at both ends of the motor stator, and the axial magnetic bearing is located outside the radial magnetic bearings.

Preferably, the motor stator, the radial bearing stator and the axial bearing stator positioned on the inner side of the thrust disc are fixed on the motor shaft through interference fit with the outer surface of the motor shaft, and the axial bearing stator positioned on the outer side of the thrust disc is in clearance fit with the outer surface of the motor shaft and is fixed on the motor shaft through a locking nut; the motor rotor and the radial bearing rotor are fixed on the rotor seat through interference fit with the inner hole of the rotor seat, and the thrust disc is in clearance fit with the inner hole of the rotor seat and is fixed on the rotor seat through screws.

Preferably, the axial bearing stator comprises an axial stator seat and an axial winding coil; the axial stator seat is provided with an axial stator hole, and the axial stator hole is in interference fit with the outer surface of the motor shaft; the axial winding coil is fixed in the axial stator seat, and the axial winding coil is positioned on one side close to the thrust disc.

Preferably, the magnetic bearing device further comprises a front protection bearing and a rear protection bearing, and inner rings of the front protection bearing and the rear protection bearing are respectively sleeved at two ends of the motor shaft in an interference fit manner; gaps exist between outer rings of the front protection bearing and the rear protection bearing and the rotor seat, and the distance of the gaps is respectively smaller than the gap distance between the motor stator and the motor rotor, the gap distance between the radial bearing stator and the radial bearing rotor, and the gap distance between an inner hole of the thrust disc and the surface of the motor shaft.

Preferably, the air inlet end of the fan barrel is provided with a fairing, and the fairing is located at the front end of the inlet guide vane and used for changing the flow direction of the airflow and reducing the noise of the fan.

Preferably, the axial flow fan is a binary flow impeller or a ternary flow impeller.

Preferably, the motor shaft is provided with a plurality of radial wire holes in the radial direction and axial wire holes in the axial direction, and both ends of the plurality of radial wire holes are respectively communicated with the outside of the motor shaft and the axial wire holes.

Preferably, the motor shaft is further fixedly provided with a plurality of radial sensors and a plurality of radial measured bodies, the plurality of radial sensors are respectively located at two ends of the motor shaft and are respectively arranged opposite to the plurality of radial measured bodies, and the radial sensors are used for detecting radial displacement of the rotor base.

Preferably, the rotor seat is fixedly provided with an axial measured body, and the outlet guide vane is fixedly provided with an axial sensor; the axial sensor is arranged opposite to the axial measured body and is used for detecting the axial displacement of the rotor seat.

The axial flow fan adopting the magnetic suspension outer rotor has the advantages that:

when the axial flow fan works: the motor stator is electrified to drive the motor rotor so as to drive the rotor seat to rotate; the radial bearing rotor and the thrust disc rotate along with the rotor seat, the radial bearing stator provides radial magnetic support for the radial bearing rotor so as to limit the rotor seat in the radial direction, and the plurality of axial bearing stators provide axial magnetic support for the thrust disc so as to limit the rotor seat in the axial direction; the rotor base rotates to drive the axial flow fan to rotate to generate air flow, air enters the axial flow fan from the air inlet end of the fan barrel through the inlet guide vane for rectification and is accelerated, and the accelerated air is discharged after being rectified through the outlet guide vane. In the mode, the exhaust volume of the axial flow fan is large, the axial flow fan can radiate heat for the axial flow fan, and a cooling system is not needed. Meanwhile, when the rotor seat rotates, the radial direction and the axial direction of the rotor seat are supported and limited through a radial magnetic bearing and an axial magnetic bearing respectively; the radial magnetic bearing and the axial magnetic bearing support and limit the rotor seat by utilizing magnetic force without mechanical contact, so that the rotor seat can have higher rotating speed; and then the volume that leads to rotor seat and axial fan's blade to be can be done is littleer to reduce the cost of equipment, reduced the space that needs occupy when installing.

Drawings

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

Fig. 2 and 3 are schematic structural views of the blower barrel.

Fig. 4 is a schematic view of the structure of the motor shaft.

Fig. 5 is a schematic structural view of an axial bearing stator.

Fig. 6 and 7 are schematic structural views of the outlet guide vane.

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

L-air flow direction, 12-outlet holes, 13-silicon steel sheets and 14-magnetic steel.

Detailed Description

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

Example 1

As shown in fig. 1 to 9, an axial flow fan using a magnetic levitation outer rotor includes a fan cylinder 1, a motor shaft 2, a rotor base 3, an axial flow fan 4, a motor stator 5, a motor rotor 6, a magnetic bearing device 7, an inlet guide vane 8, and an outlet guide vane 9; the motor shaft 2 is fixed on the fan barrel 1, a rotor seat inner hole is arranged in the rotor seat 3, and the magnetic bearing device 7 comprises a radial magnetic bearing 71 and an axial magnetic bearing 72; the radial magnetic bearing 71 includes a radial bearing stator 73 and a radial bearing rotor 74 that are disposed opposite to each other, and the axial magnetic bearing 72 includes a thrust disk 75 and a plurality of axial bearing stators 76 located at both axial ends thereof; the motor stator 5, the radial bearing stator 73 and the axial bearing stator 76 are fixedly sleeved on the motor shaft 2, and the motor rotor 6, the radial bearing rotor 74 and the thrust disc 75 are fixedly embedded in the inner hole of the rotor seat; the axial flow fan 4 is fixedly arranged on the outer wall of the rotor seat 3; the inlet guide vane 8 and the outlet guide vane 9 are fixed to the blower case 1 and are respectively located at both axial ends of the axial flow fan 4. When the axial flow fan works: the motor stator 5 is electrified to drive the motor rotor 6 so as to drive the rotor seat 3 to rotate; the radial bearing rotor 74 and the thrust disk 75 rotate with the rotor base 3, the radial bearing stator 73 provides radial magnetic support for the radial bearing rotor 74 to radially limit the rotor base 3, and the plurality of axial bearing stators 76 provides axial magnetic support for the thrust disk 75 to axially limit the rotor base 3; the rotor seat 3 rotates to drive the axial flow fan 4 to rotate to generate air flow, air enters the axial flow fan 4 from the air inlet end of the fan cylinder 1 through the inlet guide vane 8 for rectification and is accelerated, and the accelerated air is discharged after being rectified through the outlet guide vane 9. In the mode, the exhaust volume of the axial flow fan is large, the axial flow fan can radiate heat for the axial flow fan, and a cooling system is not needed. Meanwhile, when the rotor base 3 rotates, the radial direction and the axial direction of the rotor base are supported and limited by a radial magnetic bearing 71 and an axial magnetic bearing 72 respectively; the radial magnetic bearing 71 and the axial magnetic bearing 72 support and limit the rotor holder 3 by using magnetic force without mechanical contact, so that the rotor holder 3 can have high rotating speed; and further, the volume that the blades of the rotor base 3 and the axial fan 4 can be made is smaller, so that the cost of the equipment is reduced, and the space required to be occupied during installation is reduced.

The plurality of radial magnetic bearings 71 are respectively located at both ends of the motor stator 5, and the axial magnetic bearing 72 is located outside the radial magnetic bearings 71. The motor stator 5, the radial bearing stator 73 and the axial bearing stator 76 positioned on the inner side of the thrust disc 75 are fixed on the motor shaft 2 through interference fit with the outer surface of the motor shaft 2, and the axial bearing stator 76 positioned on the outer side of the thrust disc 75 is in clearance fit with the outer surface of the motor shaft 2 and is fixed on the motor shaft 2 through a locking nut; the motor rotor 6 and the radial bearing rotor 74 are fixed on the rotor base 3 by interference fit with the rotor base inner hole, and the thrust disc 75 is clearance fit with the rotor base inner hole and fixed on the rotor base 3 by screws.

As shown in fig. 5, axial bearing stator 76 includes an axial stator seat 761 and axial winding coils 762; the axial stator seat 761 is provided with an axial stator hole 763, and the axial stator hole 763 is in interference fit with the outer surface of the motor shaft 2; axial winding coils 762 are fixed in axial stator seat 761 and axial winding coils 762 are located near one side of thrust disk 75 to provide magnetic force to thrust disk 75 to restrain it with its own magnetic field.

As shown in fig. 1, the magnetic bearing device 7 further includes a front protection bearing 77 and a rear protection bearing 78, inner rings of the front protection bearing 77 and the rear protection bearing 78 are respectively sleeved at two ends of the motor shaft 2 in an interference manner; a gap exists between the outer ring of each of the front protection bearing 77 and the rear protection bearing 78 and the rotor base 3, and the distance of the gap is smaller than the gap distance between the motor stator 5 and the motor rotor 6, the gap distance between the radial bearing stator 73 and the radial bearing rotor 74, and the gap distance between the inner hole of the thrust disc 75 and the surface of the motor shaft 2. When the axial flow fan is not energized or suddenly de-energized, the radial magnetic bearing 71 and the axial magnetic bearing 72 cannot provide support for the rotor holder 3 due to the non-energization; at this time, the rotor seat 3 falls down to be respectively contacted with the outer rings of the front protective bearing 77 and the rear protective bearing 78, the motor stator 5 is not contacted with the motor rotor 6, the radial bearing stator 73 is not contacted with the radial bearing rotor 74, and the inner hole of the thrust disc 75 is not contacted with the surface of the motor shaft 2; therefore, the rotor base 3 is supported by the front protection bearing 77 and the rear protection bearing 78, and the rotor base 3 is prevented from suddenly falling and being damaged without being supported when the axial flow fan is powered off, and the motor stator 5 and the motor rotor 6, the radial bearing stator 73 and the radial bearing rotor 74, and the inner hole of the thrust disc 75 and the motor shaft 2 are prevented from colliding with each other and being damaged when the rotor base 3 falls.

The air inlet end of the fan barrel 1 is provided with a fairing 11, and the fairing 11 is located at the front end of the inlet guide vane 8 and used for changing the flowing direction of air flow and reducing the noise of the fan. The axial flow fan 4 is a binary flow impeller or a ternary flow impeller.

As shown in fig. 4, the motor shaft 2 is provided with a plurality of radial lead holes 21 in the radial direction and axial lead holes 22 in the axial direction, and both ends of the plurality of radial lead holes 21 communicate with the outside of the motor shaft 2 and the axial lead holes 22, respectively. The lines of the motor stator 5, the radial magnetic bearing 71, the axial magnetic bearing 72 and other parts pass through the radial wire guide 21 and are collected to the axial wire guide 22, and then are discharged from the axial wire guide 22, so that the line arrangement of the axial flow fan is facilitated.

As shown in fig. 8 and 9, the motor shaft 2 is further fixedly provided with a plurality of radial sensors 23 and a plurality of radial measured objects, the plurality of radial sensors 23 are respectively located at two ends of the motor shaft 2 and are respectively opposite to the plurality of radial measured objects, the radial sensors 23 are used for detecting radial displacement of the rotor holder 3, and the radial magnetic bearing 71 controls the radial position of the rotor holder 3 according to signals of the radial sensors 23. The rotor seat 3 is fixedly provided with an axial measured body 31, and the outlet guide vane 9 is fixedly provided with an axial sensor 91; the axial sensor 91 is disposed opposite to the axial measured body 31, the axial sensor 91 is used for detecting the axial displacement of the rotor holder 3 and the axial magnetic bearing 72 controls the axial position of the rotor holder 3 according to the signal of the axial sensor 91.

Claims

1. An axial flow fan adopting a magnetic suspension outer rotor is characterized by comprising a fan cylinder (1), a motor shaft (2), a rotor seat (3), an axial flow fan (4), a motor stator (5), a motor rotor (6), a magnetic bearing device (7), an inlet guide vane (8) and an outlet guide vane (9); the motor shaft (2) is fixed on the fan barrel (1), a rotor seat inner hole is arranged in the rotor seat (3), and the magnetic bearing device (7) comprises a radial magnetic bearing (71) and an axial magnetic bearing (72); the radial magnetic bearing (71) comprises a radial bearing stator (73) and a radial bearing rotor (74) which are oppositely arranged, and the axial magnetic bearing (72) comprises a thrust disc (75) and a plurality of axial bearing stators (76) which are positioned at two axial ends of the thrust disc; the motor stator (5), the radial bearing stator (73) and the axial bearing stator (76) are fixedly sleeved on the motor shaft (2), and the motor rotor (6), the radial bearing rotor (74) and the thrust disc (75) are fixedly embedded in the inner hole of the rotor seat; the axial flow fan (4) is fixedly arranged on the outer wall of the rotor seat (3); the inlet guide vane (8) and the outlet guide vane (9) are fixed on the fan barrel (1) and are respectively positioned at two axial ends of the axial flow fan (4).

2. Axial fan with magnetically levitated outer rotor according to claim 1, characterized in that a plurality of radial magnetic bearings (71) are respectively located at both ends of the motor stator (5), and the axial magnetic bearing (72) is located outside the radial magnetic bearings (71).

3. The axial flow fan with the magnetic suspension outer rotor is characterized in that the motor stator (5), the radial bearing stator (73) and the axial bearing stator (76) positioned on the inner side of the thrust disc (75) are fixed on the motor shaft (2) through interference fit with the outer surface of the motor shaft (2), and the axial bearing stator (76) positioned on the outer side of the thrust disc (75) is in clearance fit with the outer surface of the motor shaft (2) and is fixed on the motor shaft (2) through a locking nut; the motor rotor (6) and the radial bearing rotor (74) are fixed on the rotor seat (3) through interference fit with the inner hole of the rotor seat, and the thrust disc (75) is in clearance fit with the inner hole of the rotor seat and is fixed on the rotor seat (3) through screws.

4. Axial fan with magnetic levitation external rotor according to claim 1, characterized in that the axial bearing stator (76) comprises an axial stator seat (761) and axial winding coils (762); the axial stator seat (761) is provided with an axial stator hole (763), and the axial stator hole (763) is in interference fit with the outer surface of the motor shaft (2); the axial winding coils (762) are fixed in the axial stator seat (761) and the axial winding coils (762) are located on the side close to the thrust disc (75).

5. The axial flow fan adopting the magnetic suspension outer rotor is characterized in that the magnetic bearing device (7) further comprises a front protection bearing (77) and a rear protection bearing (78), inner rings of the front protection bearing (77) and the rear protection bearing (78) are respectively sleeved at two ends of the motor shaft (2) in an interference manner; gaps exist between outer rings of the front protective bearing (77) and the rear protective bearing (78) and the rotor seat (3), and the distances of the gaps are respectively smaller than the gap distance between the motor stator (5) and the motor rotor (6), the gap distance between the radial bearing stator (73) and the radial bearing rotor (74), and the gap distance between an inner hole of the thrust disc (75) and the surface of the motor shaft (2).

6. The axial flow fan with the magnetic suspension outer rotor is characterized in that a fairing (11) is arranged at the air inlet end of the fan barrel (1), and the fairing (11) is located at the front end of the inlet guide vane (8) and used for changing the flow direction of air flow and reducing the noise of the fan.

7. Axial fan with magnetic levitation external rotor according to claim 1, characterized in that the axial fan (4) is a binary flow impeller or a ternary flow impeller.

8. The axial flow fan with magnetic suspension outer rotor as recited in claim 1, wherein the motor shaft (2) is provided with a plurality of radial wire holes (21) in a radial direction and axial wire holes (22) in an axial direction, and both ends of the plurality of radial wire holes (21) are respectively communicated with the outside of the motor shaft (2) and the axial wire holes (22).

9. The axial flow fan with the magnetic levitation outer rotor is characterized in that the motor shaft (2) is further fixedly provided with a plurality of radial sensors (23) and a plurality of radial measured bodies, the plurality of radial sensors (23) are respectively located at two ends of the motor shaft (2) and are respectively opposite to the plurality of radial measured bodies, and the radial sensors (23) are used for detecting radial displacement of the rotor base (3).

10. The axial flow fan with the magnetic suspension outer rotor is characterized in that an axial measured body (31) is fixedly arranged on the rotor seat (3), and an axial sensor (91) is fixedly arranged on the outlet guide vane (9); the axial sensor (91) is arranged opposite to the axial measured body (31), and the axial sensor (91) is used for detecting the axial displacement of the rotor seat (3).