Pneumatic cross-flow fan with turbine and permanent magnet motor integrated structure

Abstract

The air compression type cross-flow fan of the turbine and permanent magnet motor integrated structure comprises an impeller, the impeller comprises a circular ring piece, blades are fixed to the shaft end of one side of the circular ring piece, and the multiple blades are arranged around the axis of the impeller in an annular array mode; the stator assembly is arranged on one axial side of the impeller; the rotor assembly comprises rotor magnetic steel assembled at the tail ends of the blades; the fan shell wraps the stator assembly and the rotor assembly; wherein an axial air gap is formed between the stator assembly and the rotor assembly, and the impeller and the rotor assembly have the degree of freedom of synchronous rotation relative to the stator assembly. Therefore, the rotor magnetic steel can also play a role in driving airflow when rotating along with the blades. The rotor assembly can be regarded as a part of a motor and can also be regarded as a part of fan blades, so that the axial size of the cross-flow fan can be smaller. In addition, airflow can pass around the rotor assembly and the stator assembly, and the air cooling effect is good.

Description

Technical Field

[0001] The present application relates to the field of fans, and in particular to a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor. Background Art

[0002] Fans include crossflow fans and axial flow fans. Crossflow fans usually adopt the form of coaxial axial connection between the fan and the permanent magnet drive motor. The main principle is that the motor drives the fan blades to convert electrical energy into mechanical energy, and the rotating fan blades do work on the working fluid. In traditional crossflow fans, the drive motor and the crossflow fan are manufactured separately and then assembled later. This form has simple process and relatively low cost, so it can be widely used.

[0003] However, the technical solution of the traditional crossflow fan in series with a permanent magnet motor requires the use of transmission components such as a power shaft and a coupling, because the motor and the fan blades are installed as independent components. This will generate additional energy losses, making the motor rotor of the crossflow fan more susceptible to unbalanced forces, thereby generating vibrations. In order to avoid the dynamic problems caused by crossing the critical speed, the methods known to the inventors are generally to improve the coupling or increase the shaft diameter of the power shaft. However, due to the limitation of the tangential speed of the rotor, it is difficult for the traditional crossflow fan and its series motor to actually achieve a very high speed, which ultimately leads to a larger size and low power density of the motor connected in series with the crossflow fan. The speed limit also limits the maximum compression ratio of the compressed air crossflow fan.

[0004] The Chinese invention patent with the publication number of "CN108678976A" discloses "a small wet and dry vacuum cleaner electric blower". The electric blower includes a waterproof isolation cover, a blower blade, a permanent magnet motor, and an air inlet cover. The front end surface of the waterproof isolation cover is formed with an air guide wheel structure. The blower blades are arranged on the front side of the waterproof isolation cover. The permanent magnet motor is installed in the installation cavity of the waterproof isolation cover, and the motor shaft of the permanent magnet motor extends forward from the front end surface of the waterproof isolation cover and is connected to the blower blades. The air inlet cover is covered on the front end surface of the waterproof isolation cover, and an air inlet is opened in the middle of the air inlet cover, and the blower blades are located in the air inlet cover and opposite to the air inlet position. The permanent magnet motor and the blower blades in the electric blower are independent components, and an air guide wheel is also arranged between the two. The output shaft of the permanent magnet motor needs to pass through the air guide wheel and then be fixed to the blower blades. This axial force transmission will inevitably result in certain energy losses and vibrations, and the maximum speed also has an inherent upper limit. Summary of the invention

[0005] This application is made in view of the above-mentioned state of the prior art. The purpose of this application is to provide a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor.

[0006] The technical solution adopted in the present application includes: an impeller, the impeller includes a circular ring plate, a blade is fixed to one axial end of the circular ring plate, and a plurality of the blades are arranged in a circular array around the axis of the impeller; a stator assembly, the stator assembly is arranged on one axial side of the impeller; a rotor assembly, the rotor assembly includes a rotor magnet assembled on the end of the blade; a fan casing, the fan casing wraps the stator assembly and the rotor assembly; wherein an axial air gap is formed between the stator assembly and the rotor assembly, and the impeller and the rotor assembly have the freedom to rotate synchronously relative to the stator assembly.

[0007] As a further improvement of the present application, the rotor magnet and the blades are an integrated magnetic conductive component, or the rotor magnet and the blades are independent components and are assembled together by fasteners.

[0008] As a further improvement of the present application, the rotor magnet and the blades are assembled with each other through countersunk bolts, and the axis of the countersunk bolts is parallel to the axis of the impeller.

[0009] As a further improvement of the present application, in the cross-sectional direction of the impeller, the cross-sectional profiles of the blades and the rotor magnets are the same; the cross-sectional profile of the blades or the rotor magnets is one or a combination of streamlined, elliptical, and diamond shapes.

[0010] As a further improvement of the present application, the stator assembly includes a stator core and a winding, the stator core includes a circular ring portion, an axial protrusion is fixed to one axial end of the circular ring portion, a plurality of the axial protrusions are arranged in a circular array around the axis of the stator assembly, and the side of the axial protrusion is wound with a winding.

[0011] As a further improvement of the present application, the axial extension direction of the axial protrusion is parallel to the axial extension direction of the blade; and the sum of the axial lengths of the blade and the rotor magnetic steel is greater than the axial length of the axial protrusion.

[0012] As a further improvement of the present application, the number of the rotor magnets is not equal to the number of the axial protrusions.

[0013] As a further improvement of the present application, the fan casing includes a main shell and an end cover; the main shell has a cylindrical cavity for accommodating the rotor assembly, and the main shell also includes an air inlet and an air outlet connected to the cylindrical cavity, and the air inlet and the air outlet each extend in a direction perpendicular to the axis of the main shell; the end cover is assembled with one end of the stator assembly.

[0014] As a further improvement of the present application, a convex shaft is protruded from the inner wall of the main shell, and the convex shaft and the annular sheet are movably assembled through a bearing, and the impeller has the freedom of rotation around the convex shaft.

[0015] As a further improvement of the present application, the bearing is coaxially arranged with an outer retaining ring and an inner retaining ring, the outer retaining ring and the inner retaining ring are in contact with the same axial end of the bearing, the outer retaining ring jointly contacts the outer ring of the bearing and the annular sheet, and the inner retaining ring jointly contacts the inner ring of the bearing and the convex shaft.

[0016] The beneficial effects of the compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application include:

[0017] First of all, the rotor assembly and the stator assembly form a motor that can provide rotational force to the crossflow fan, and the impeller can drive the airflow. At the same time, since the rotor magnet of the rotor assembly is fixed at the end of the blade, the existence of the rotor magnet is equivalent to extending the length of the blade. The rotor magnet can also drive the airflow when it rotates with the blade, thereby equivalently forming a larger fan blade. The rotor assembly can be regarded as part of the motor or as part of the fan blade, that is, there is a certain axial overlap between the motor and the fan blade. This allows the axial dimension of the crossflow fan to be compressed, giving it a flat appearance, good overall structural compactness, and a high degree of integration, which is suitable for use in some scenarios with limited axial dimensions.

[0018] Secondly, the rotor assembly will rotate relative to the stator assembly, and the rotor assembly directly drives the impeller to rotate, that is, there is no traditional power shaft and coupling between the motor and the fan blades, and the long power shaft for transmitting the rotational power is eliminated. This reduces the number of parts and shortens the axial distance between the motor and the fan blades, making the transmission of rotational power faster and less prone to vibration problems caused by the long power shaft in the prior art. This makes it easier to increase the maximum operating speed of the entire crossflow fan, and improve the power density and maximum compression ratio.

[0019] Finally, the fan housing provides a cavity for the crossflow fan, which is convenient for the airflow to enter and exit. Because the rotor assembly will inevitably drive the airflow, the airflow of the crossflow fan will also pass through the air gap, passing around the rotor assembly and the stator assembly. The passing airflow can also heat and cool the motor, achieving the effect of air cooling. Therefore, without adding additional cooling mechanisms, the maximum speed and maximum power of the crossflow fan can be increased, and it can cope with the cooling of high temperatures at high speeds.

[0020] This type of crossflow fan is suitable for many fields such as industrial equipment cooling, HVAC, automotive battery cooling, etc. It is particularly suitable for applications that require stable wind pressure and efficient air flow distribution, and is also suitable for occasions where there are restrictions on the axial volume of the crossflow fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 It is an exploded view of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0023] Figure 2 It is a three-dimensional diagram of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0024] Figure 3 It is an assembly diagram of a stator assembly and an end cover of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0025] Figure 4 It is an assembly diagram of a rotor assembly, an impeller and a main housing of an embodiment of a compressed air crossflow fan having an integrated structure of an impeller machine and a permanent magnet motor of the present application;

[0026] Figure 5 It is an assembly diagram of a stator assembly, a rotor assembly, and an impeller of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller machine and a permanent magnet motor of the present application;

[0027] Figure 6 It is an assembly diagram of a rotor assembly and an impeller of an embodiment of a compressed air crossflow fan having an integrated structure of an impeller machine and a permanent magnet motor of the present application;

[0028] Figure 7 It is a top view of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application, with the end cover hidden;

[0029] Figure 8 It is a three-dimensional view of the main housing of an embodiment of a compressed air crossflow fan having an integrated structure of an impeller and a permanent magnet motor of the present application;

[0030] Fig. 9 It is a bottom view of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0031] Fig.10 yes Fig. 9 AA section view;

[0032] Fig.11It is a force path diagram of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0033] Fig.12 It is a side view of an embodiment of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0034] Fig.13 yes Fig.12 BB cross-sectional view;

[0035] Fig.14 It is a three-dimensional diagram of the rotor magnet of one embodiment of a compressed air crossflow fan having an integrated structure of an impeller and a permanent magnet motor of the present application;

[0036] Fig.14 (a) is a perspective view of a first embodiment of the rotor magnet of a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application;

[0037] Fig.14 (b) is a perspective view of a second embodiment of the rotor magnet of the compressed air crossflow fan with an integrated structure of the impeller and the permanent magnet motor of the present application;

[0038] Fig.14 (c) is a stereoscopic view of a third embodiment of the rotor magnet of a compressed air cross-flow fan having an integrated structure of an impeller and a permanent magnet motor according to the present application.

[0039] Description of Reference Numerals

[0040] 1-impeller; 101-circular ring; 1011-circular groove; 1012-circular rib; 102-blade; 2-rotor magnet; 3-main housing; 301-cylindrical cavity; 302-air inlet; 3021-air inlet; 303-air outlet; 3031-air outlet; 304-shaft end opening; 305-concave stopper; 306-convex shaft portion; 4-end cover; 401-convex stopper; 5-rotor assembly; 6-fan casing; 7-stator assembly; 8-gland head; 9-stator core; 901-circular ring portion; 902-axial protrusion; 10-winding; 1001-hollow cavity; 11-bearing; 12-outer retaining ring; 13-inner retaining ring; 14-countersunk bolt; 15-trailing edge; 16-leading edge; 17-windward side; 18-leeward side; 19-air gap. DETAILED DESCRIPTION

[0041] The exemplary embodiments of the present application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present application, and are not intended to exhaust all possible methods of the present application, nor to limit the scope of the present application.

[0042] See also Figure 1 , Figure 6 , Fig.10 , an embodiment of the present application provides a compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor. The crossflow fan includes an impeller 1, a stator assembly 7, a rotor assembly 5 and a fan casing 6. The impeller 1 includes an annular plate 101, and a blade 102 is fixed to one axial end of the annular plate 101, and a plurality of blades 102 are arranged in a circular array around the axis of the impeller 1. The stator assembly 7 is arranged on one axial side of the impeller 1. The rotor assembly 5 includes a rotor magnet 2 assembled at the end (i.e., the top) of the blade 102. That is, in the axial direction ( Fig.10 In the left and right direction), the rotor assembly 5 is arranged between the impeller 1 and the stator assembly. The fan housing 6 wraps the stator assembly 7 and the rotor assembly 5. Fig.10 As shown, the stator assembly 7 and the rotor assembly 5 are not in contact and form an axial air gap 19 (axial gap), and the impeller 1 and the rotor assembly 5 have the freedom of synchronous rotation relative to the stator assembly 7. Among them, the impeller 1 is the impeller 1 of the crossflow distributor, the rotor assembly 5 is the rotor assembly 5 of the permanent magnet motor, and the stator assembly 7 is the stator assembly 7 of the permanent magnet motor (axial flux motor). The rotor assembly 5 and the stator assembly 7 together constitute a motor, that is, an axial flux motor.

[0043] The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application utilizes an integrated structure to fix the impeller 1 and the rotor magnet 2 together. Compared with the traditional axial series crossflow fan drive structure, the compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application can significantly shorten the axial length, which is equivalent to eliminating the common power shaft in the motor, thereby increasing the upper limit of the motor operating speed. Under the same output power, the motor torque can be relatively reduced, thereby increasing the power density of the crossflow fan drive motor and enhancing the boost capacity of the crossflow fan.

[0044] In one embodiment, if Figure 1 , Figure 6 As shown, the rotor magnet 2 and the blade 102 are assembled together by fasteners. Cutting along the cross-sectional direction of the impeller 1, the blade 102 and the rotor magnet 2 have the same cross-sectional profile.

[0045] The beneficial effect of adopting the above embodiment is that when observed from the axial perspective of the impeller 1, the rotor magnet 2 and the blade 102 are completely overlapped, so that the rotor magnet 2 and the outer wall of the blade 102 are smoothly transitioned. The rotor magnet 2 can also play an equivalent function of driving the airflow, and the rotor magnet 2 and the blade 102 together form a fan blade with a larger area. The geometric properties of the blade 102 include the radial length of the blade 102, the height of the blade 102 (i.e., the axial length), the cross-sectional shape of the blade 102, the arc type of the blade 102, and the shape of the leading edge and trailing edge of the blade 102, so that the cross-sectional shape of the rotor magnet 2 is consistent with the cross-sectional shape of the blade 102, thereby ensuring the consistency of the outer surface of the fan blade, and rotor magnets 2 of different shapes can be selected according to the different configurations of the blade 102.

[0046] In one embodiment, the annular sheet 101 and the blade 102 in the impeller 1 can be integrally connected, and the impeller 1 is manufactured in one piece, which can ensure the overall structural strength of the impeller 1. The blade 102 itself forms a cantilever structure, that is, the blade 102 has a top and a root. The impeller 1 and the rotor assembly 5 can be parameter-designed according to specific application scenarios and performance requirements, and the rotor assembly 5 participates in the formation of the motor magnetic circuit and needs to be manufactured by magnetic conductive materials. The rotor magnetic steel 2 can be first processed by metal milling or 3D additive manufacturing technology, and then the rotor magnetic steel 2 and the blade 102 are fixed in a stamping stacking form. In this case, only the rotor magnetic steel 2 needs to be made of magnetic conductive material, and the material of the impeller 1 is not limited. Alternatively, the impeller 1 and the rotor assembly 5 are originally the same blank, and the rotor magnetic steel 2 and the blade 102 are processed on the blank respectively, and the rotor magnetic steel 2 and the blade 102 can always remain integral without being cut. In this case, the blank needs to be made of magnetic conductive material.

[0047] The beneficial effects of adopting the above embodiment are: from a functional perspective, the rotor magnet 2 can be classified as a part of the motor or a part of the fan blade. From a processing perspective, the rotor magnet 2 and the blade 102 can be an integral blank, processed simultaneously with the same material, or different materials and different processing sequences can be processed successively, and then assembled with each other. The specific method can be selected from the perspective of actual processing.

[0048] In one embodiment, the fastener used to assemble the rotor magnet 2 and the blade 102 may be a bolt, and the axis of the bolt is parallel to the axis of the impeller 1. The axial length of the bolt is greater than the axial length of the rotor magnet 2, and the bolt penetrates the rotor magnet 2, thereby fixing the rotor magnet 2 to the end of the blade 102. The end of the blade 102 is provided with an internal threaded blind hole assembled with the bolt.

[0049] In a non-limiting example, Figure 1 , Figure 6As shown, the bolt can be a countersunk bolt 14, and the rotor magnet 2 has a countersunk through hole. The end of the countersunk bolt 14 is located inside the countersunk through hole. The countersunk bolt 14 will not be exposed from the surface of the rotor magnet 2 after being fixed, so the countersunk bolt 14 has less effect on the overall shape of the fan blade and less negative disturbance to the airflow of the cross-flow fan.

[0050] In a non-limiting example, each blade 102 and the rotor magnet 2 can be fixed by means of one or more countersunk bolts 14. In addition, the facing surfaces of the blade 102 and the rotor magnet 2 can be provided with a concave-convex matching tenon, or with a circle of stoppers, so as to facilitate the stable pre-fixation of the blade 102 and the rotor magnet 2 during assembly, and then use the countersunk bolts 14 to achieve locking. This ensures that the mutual assembly of the blade 102 and the rotor magnet 2 will not be misaligned. In this case, even if only one countersunk bolt 14 is used for each rotor magnet 2, the rotor magnet 2 and the blade 102 can be accurately and stably fixed.

[0051] The axial lengths of the stator assembly 7 and the rotor assembly 5 are related to the electromagnetic design. The sum of the lengths of the stator assembly 7 and the rotor assembly 5 is mainly to meet the aerodynamic requirements and the requirements of the electromagnetic air gap 19 to ensure the entire magnetic field loop. The axial length of the rotor assembly 5 can be greater than the axial length of the stator assembly 7. The axial lengths of the stator assembly 7 and the rotor assembly 5 determine the width of the air gap 19 between the stator assembly 7 and the rotor assembly 5. The blades 102 need to meet the airflow compression and flow requirements. When the total axial lengths of the stator assembly 7 and the rotor assembly 5 are determined, the relative lengths of the stator assembly 7 and the rotor assembly 5 are determined by the electromagnetic performance.

[0052] In the compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application, the rotor assembly 5 is designed to be integrated with the impeller 1, and the rotor assembly 5 is equivalent to constituting a part of the impeller 1. Or conversely, the impeller 1 is processed with a magnetic conductive material, so that a part of the impeller 1 is used as the rotor assembly 5.

[0053] The combination of the rotor assembly 5 and the impeller 1 takes into account the comprehensive impact of the structures of the two on the electromagnetic and aerodynamic performance. The motor formed by the rotor assembly 5 and the stator assembly 7 is an axial flux motor. The magnetic field loop uses the stator assembly 7 as the source of the magnetic field, and forms a closed magnetic field line circulation path along the axial direction with the rotor assembly 5 through the air gap 19. The periodic change of its magnetic field promotes the normal operation of the motor. During operation, the rotor assembly 5 and the impeller 1 are driven to rotate synchronously through the change of the magnetic field, thereby sucking the gas into the fan housing 6, and then the airflow is accelerated and pressurized through the rotor assembly 5 and the impeller 1, and finally discharged from the fan housing 6.

[0054] In a non-limiting example, the rotor magnetic steel 2 is a permanent magnetic material, and the rotor magnetic steel 2 can be a permanent magnetic material containing an iron-based alloy, or a permanent magnetic material without a traditional steel component. In order to increase the magnetic flux density of the air gap 19 in the motor, the rotor magnetic steel 2 uses a neodymium iron boron permanent magnet or a samarium cobalt permanent magnet with high remanence and high coercivity. The specific selection is based on the comprehensive optimization of the working environment and performance requirements.

[0055] like Figure 6 As shown, the number of rotor magnets 2 is consistent with the number of blades 102, and the number of blades 102 will also affect the density of the crossflow fan. In addition, the airflow disturbed by the blades 102 can also achieve thermal management of the rotor assembly 5. When the speed of the impeller 1 increases, the flow rate of the inlet and outlet airflow will increase, that is, the flow rate of the airflow flowing through the rotor assembly 5 area will be increased, and the convection heat exchange effect between the airflow and the rotor assembly 5 will be enhanced, thereby offsetting the incremental eddy current loss of the rotor assembly 5 caused by the increase in speed, and achieving an increase in the maximum speed and maximum power without adding additional cooling components.

[0056] In a non-limiting example, Figure 4 , Figure 6 As shown, since the blade 102 and the blade after the rotor magnet 2 is fixed are both cantilever structures, a ring-shaped member can be fixed at the end of the blade 102 or the rotor magnet 2. The ring-shaped member can be made of non-magnetic material. The existence of the ring-shaped member may slightly reduce the flow area of ​​the cross-flow fan, but the ring-shaped member can fix the end of the blade 102 or the rotor magnet 2 to each other, thereby improving the cantilever structure of the blade 102, greatly improving the overall structural strength, and reducing the possibility of vibration of the blade 102 during high-speed rotation.

[0057] In one embodiment, if Fig.14 As shown, the cross-sectional profile of the rotor magnetic steel 2 can be as follows Fig.14 The streamline shape shown in (a) can also be Fig.14 (c) The ellipse shown in FIG. Fig.14 (b) Other shapes such as rhombus. Figures 1 to 13 The rotor magnets 2 in the figure are all in streamline shape as examples.

[0058] The beneficial effects of the above embodiment are: from the perspective of aerodynamics, streamlined blades 102 are the best, but blades 102 with elliptical or diamond cross sections can reduce torque fluctuations, and blades 102 with elliptical or diamond cross sections can also easily make the rotor magnet 2 larger, which is beneficial from the perspective of electromagnetic force. Blades 102 with different cross-sectional shapes have their own advantages and disadvantages, and can be selected according to actual operational requirements.

[0059] like Fig.12 , Fig.13As shown, the streamlined surface is composed of convex surfaces and concave surfaces, the windward surface 17 is a convex surface, the leeward surface 18 is a concave surface, the position of the blade 102 that first contacts the incoming airflow is the leading edge 16, and the position that contacts the incoming airflow later is the trailing edge 15. Compared with the trailing edge 15, the leading edge 16 is relatively blunter. Fig.13 The straight solid arrows used in the figure represent the entry and exhaust of airflow, and the curved solid arrows used in the figure represent the rotational motion of airflow inside the cross-flow fan.

[0060] In one embodiment, if Figure 1 , Figure 5 As shown, the stator assembly 7 includes a stator core 9 and a winding 10. The stator core 9 includes a circular ring portion 901. An axial protrusion 902 is fixed to one axial end of the circular ring portion 901. Figure 1 , Figure 5 The side of the annular portion 901 facing downward, that is, the side of the annular portion 901 facing the rotor magnet 2 is fixed with an axial protrusion 902. A plurality of axial protrusions 902 are arranged in an annular array around the axis of the stator assembly 7, and the side of the axial protrusion 902 is wound with a winding 10.

[0061] The beneficial effect of adopting the above embodiment is that the axial protrusion 902 provides a position for each winding 10 to be wound and fixed.

[0062] In one embodiment, if Figure 5 As shown, the axial extension direction of the axial protrusion 902 is parallel to the axial extension direction of the blade 102. The sum of the axial lengths of the blade 102 and the rotor magnetic steel 2 is greater than the axial extension length of the axial protrusion 902.

[0063] The beneficial effect of adopting the above embodiment is that the winding 10 is arranged relatively close to the rotor magnet 2. At the same time, the axial length of the stator assembly 7 is controlled as much as possible, so that the impeller 1 and the rotor assembly 6 occupy the limited total axial length of the crossflow fan as much as possible, so that more axial length of the crossflow fan is involved in driving the airflow.

[0064] In a non-limiting example, Figure 5 As shown, the outer walls of adjacent windings 10 (coils on adjacent axial protrusions 902) are in contact with each other, and the side of the winding 10 close to the rotor magnetic steel 2 is flush with the end of the axial protrusion 902, as shown in FIG. Fig.10 As shown, an air gap 19 is formed between the end of the rotor magnet 2 away from the cross-flow fan impeller 1 and the end of the axial protrusion 902 .

[0065] In a non-limiting example, Figure 7 As shown, the radial dimension of the entire winding 10 is larger than the radial dimension of the blade 102, that is, the axial projection of the blade 102 falls within the stator, indicating that the radial dimension of the entire stator assembly 7 is guaranteed, thereby ensuring that the electromagnetic torque can be smoothly generated between the stator assembly 7 and the rotor assembly 5.

[0066] In one embodiment, if Figure 1 As shown, the number of rotor magnetic steels 2 is not equal to the number of axial protrusions 902 (windings 10), and the number of rotor magnetic steels 2 may be greater than the number of axial protrusions 902 (windings 10). Figure 1 As shown, the number of windings 10 is 12, and the number of rotor magnets 2 is 14. The fractional slot concentrated winding 10 is adopted, the number of windings 10 is the number of slots, and the number of rotor magnets 2 is the number of rotor poles. The pole-slot combination in the following table can bring about a better magnetic flux density distribution and a relatively low torque fluctuation. The specific selection of the number of rotor magnets 2 and windings 10 can refer to the following table:

[0067]

[0068]

[0069] like Fig.11 As shown in FIG. 1 , the rotor assembly 5 is mainly subjected to the radial rotation centrifugal force and the reaction force when the air is compressed. In addition, it should also be subjected to the axial electromagnetic force, that is, Fig.11 There is a force in the left and right directions. The stator assembly 7 is subjected to an axial electromagnetic force. Fig.11 is Fig.10 Based on the drawing, Fig.11 It is also Fig.10 The local magnification of Fig.11 The solid arrows in the figure represent the transmission paths of the forces on the rotor assembly 5, the impeller 1, the bearing 11, and the main housing 3 in sequence. Fig.11 The dotted arrows in the figure represent the electromagnetic force between the rotor assembly 5 and the stator assembly 7, and the force is finally smoothly transmitted to the fan casing 6.

[0070] The magnetic lines of force form a closed path between the rotor assembly 5 and the stator assembly 7, and a closed-loop magnetic line of force path is formed between the two windings 10 that are centrally symmetrical to each other, and only one pair of windings 10 participates in forming the magnetic lines of force at the same time.

[0071] In one embodiment, if Figure 3 As shown, in the cross-sectional direction of the stator core 9, the cross-sectional profile of the axial protrusion 902 and the winding 10 is roughly an isosceles trapezoid or a sector ring. Figure 1 As shown, each winding 10 encloses a hollow cavity 1001, and the inner wall of the hollow cavity 1001 is in full surface contact with the side of the axial protrusion 902, that is, the cross-sectional profile of the hollow cavity 1001 is also roughly an isosceles trapezoid. A combination of several isosceles trapezoids or fan rings can approximately obtain a circular ring.

[0072] The beneficial effect of adopting the above embodiment is that it ensures that the axial protrusion 902 and the winding 10 are fully arranged in a limited space.

[0073] In one embodiment, if Figure 2 As shown, the fan housing 6 includes a main housing 3 and an end cover 4. Figure 8 As shown, the main housing 3 has a cylindrical cavity 301 for accommodating the rotor assembly 5, and the main opening of the cylindrical cavity 301 is the shaft end opening 304. The main housing 3 also includes an air inlet 302 and an air outlet 303 connected to the cylindrical cavity 301. The air inlet 302 and the air outlet 303 each extend in a direction perpendicular to the axis of the main housing 3, and the angle between the directions of the air inlet 302 and the air outlet 303 can be 90°. The air inlet 302 forms an air inlet 3021 on the outer wall of the main housing 3, and the air outlet 303 forms an air outlet 3031 on the outer wall of the main housing 3. The end cover 4 is assembled with one end of the stator assembly 7.

[0074] The beneficial effect of adopting the above embodiment is that the fan housing 6 can be divided into two parts, which is convenient for the assembly of internal parts. The main housing 3 is the main component of the fan housing 6, which assists in guiding the airflow. The gas enters from the air inlet 302, is accelerated by the rotation of the impeller 1, and is then discharged from the air outlet 303. The end cover 4 also fixes the stator assembly 7. The main housing 3 serves as the outer housing of the motor, which plays a structural support and protection role, and also serves as the volute of the crossflow fan. By designing the position of the opening of the main housing 3, the inlet and outlet air can be guided.

[0075] The air inlet 302 of the main housing 3 should minimize flow resistance, avoid eddy currents and unstable flow, and ensure that the airflow enters the impeller 1 smoothly. The air outlet 303 is generally designed to be radial or approximately radial so that the airflow can be discharged evenly under the action of the impeller 1.

[0076] In a non-limiting example, the end cover 4 serves as a stator fixing plate. The stator assembly 7 can be assembled with the end cover 4 in an interference fit manner, and a wire outlet seat is also arranged on the end cover 4, which is used to fix the lead wires of the stator assembly 7.

[0077] In a non-limiting example, Figure 2 As shown, the outlet seat is a cable gland 8, and the cable gland can be installed offset on one side, that is, the axis of the cable gland 8 does not coincide with the axis of the stator fixing disk.

[0078] In a non-limiting example, Fig. 9 As shown, from an axial perspective, due to the influence of the air inlet duct 302 and the air outlet duct 303 , the outline of the main shell 3 is spindle-shaped or olive-shaped, and the outline of the main shell 3 partially overlaps with the outline of the end cover 4 .

[0079] In a non-limiting example, Figure 2 As shown, when viewed from a radial perspective, the axial dimension of the main housing 3 is greater than the axial dimension of the end cover 4.

[0080] In a non-limiting example, Figure 8 As shown, the opening area of ​​the air inlet 3021 is large, and the opening area of ​​the air outlet 3031 is small, so that the air flow rate increases and the pressure rises. The air inlet 3021 and the air outlet 3031 can each have a rectangular outline. The area of ​​the air inlet 3021 and the air outlet 3031 will affect the speed of air entering and exiting the crossflow fan, and the size of the area also affects the overall flow capacity.

[0081] In one embodiment, if Figure 8 As shown, the inner wall of the main housing 3 is protruded with a protruding shaft 306. Figure 6 , Fig.10 As shown, the convex shaft 306 and the annular sheet 101 are movably assembled via the bearing 11 , and the impeller 1 has the freedom of rotation around the convex shaft 306 .

[0082] The beneficial effects of the above embodiment are: the impeller 1 is fixed in the form of a single-sided bearing, the bearing 11 makes the resistance of the impeller 1 very small when rotating, and the bearing 11 can be selected from different types of bearings 11, and the specific selection needs to be determined according to the actual force conditions. The convex shaft 306 facilitates the fixing of the bearing 11 and also facilitates the formation of a gap between the impeller 1 and the inner wall of the main housing 3, ensuring that the impeller 1 in operation will not interfere with the inner wall of the main housing 3.

[0083] In one embodiment, if Figure 1 , Fig.10 As shown, the bearing 11 is coaxially arranged with an outer retaining ring 12 and an inner retaining ring 13, and the outer retaining ring 12 and the inner retaining ring 13 are in contact with the same axial end of the bearing 11, the outer retaining ring 12 contacts the outer ring and the annular sheet 101 of the bearing 11, and the inner retaining ring 13 contacts the inner ring and the convex shaft 306 of the bearing 11. The diameter of the outer retaining ring 12 is greater than the diameter of the inner retaining ring 13, and the centroids of the outer retaining ring 12 and the inner retaining ring 13 can coincide.

[0084] The beneficial effect of adopting the above embodiment is that the outer retaining ring 12 and the inner retaining ring 13 ensure the stable assembly of the bearing 11 and the impeller 1, and the relative stability of the axis of the impeller 1 itself can be maintained even at a high speed.

[0085] In a non-limiting example, the selection of the type of bearing 11 is determined by the force conditions of the bearing 11. The bearing 11 must consider both the axial electromagnetic force and the radial centrifugal force and aerodynamic force. Therefore, the bearing 11 may preferably use a deep groove ball bearing, or use two angular contact bearings in pair.

[0086] In a non-limiting example, Figure 2, Figure 3 , Figure 8 As shown, the opening edge of the stator fixing plate has a convex stop 401, and the axial end opening 304 edge of the main housing 3 has a concave stop 305, and the convex stop 401 and the concave stop 305 are engaged with each other. In addition, the convex stop 401 and the concave stop 305 can also be further fixed by radial screws.

[0087] In a non-limiting example, Figure 5 , Figure 6 As shown, the inner ring of the annular plate 101 has an annular groove 1011, and the annular groove 1011 provides a space for accommodating the bearing 11. Because the annular groove 1011 is recessed on one side of the annular plate 101, Figure 5 , Fig.10 As shown, the other side of the corresponding annular sheet 101 is protruded with an annular rib 1012. The annular rib 1012 is convenient for ensuring that there is a certain distance between the bottom surface of the cylindrical cavity 301 and the annular sheet 101, ensuring that the rotating impeller 1 does not interfere with the inner wall of the fan housing 6.

[0088] In a non-limiting example, to prevent gas leakage, the seal between the main housing 3 and the bearing 11 can be a dynamic seal method such as a mechanical seal, a lip seal, a floating ring seal, etc. The seal between the end cover 4 and the main housing 3 can be a static seal method such as a gasket seal, an O-ring seal, a liquid sealant, etc. Liquid sealant is a semi-dry, viscoelastic liquid sealing gasket made of synthetic rubber as the main component and added with resin, additives, etc. The seal can prevent external contaminants from entering, ensure lubricant sealing, and prevent leakage of gas inside the crossflow blower.

[0089] In a non-limiting example, the material of the fan housing 6 can be 7075 aluminum alloy, which has high tensile strength and yield strength, excellent fatigue strength and stress corrosion resistance, and can ensure the lightweight and safety of the fan housing 6 structure.

[0090] The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor of the present application integrates the impeller 1 and the axial flux motor into an integrated design. By allowing the two parts to be shared, the overall axial length of the crossflow fan is reduced, and the operating speed of the impeller 1 and the rotor assembly 5 can be increased, thereby improving the power density of the axial flux motor and the boosting capacity of the impeller 1. First, the impeller 1 and the rotor magnet 2 are integrated into a design, and the geometric shape of the impeller 1 and the characteristic parameters such as the number and shape of the teeth of the rotor assembly 5 are optimized by considering the application occasions and the electromagnetic and aerodynamic performance parameter requirements. Second, the thermal management of the rotor assembly 5 is achieved through the inlet and outlet airflow of the crossflow fan, and the maximum speed of the motor can be increased without adding motor cooling accessories, and the maximum power of the motor can be increased. Third, the fan housing 6 wraps both the motor and the impeller 1, and the inside of the fan housing 6 is a complete large cavity, which further reduces the components and improves the overall compactness and lightweight. Through the optimized combination of the above three measures, the operating speed, power density and boosting capacity of the crossflow fan are improved.

[0091] The above embodiments are only for illustrating the technical concept and features of the present application, and their purpose is to enable people familiar with this technology to understand the content of the present application and implement it. They cannot be used to limit the scope of protection of the present application. All equivalent changes or modifications made according to the spirit of the present application should be included in the scope of protection of the present application.

Claims

1. A compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor, characterized in that: include: An impeller (1), the impeller (1) comprising a circular ring piece (101), a blade (102) being fixed to one axial end of the circular ring piece (101), and a plurality of blades (102) being arranged in a circular array around the axis of the impeller (1); A stator assembly (7), the stator assembly (7) being arranged on one axial side of the impeller (1); A rotor assembly (5), the rotor assembly (5) comprising a rotor magnet (2) mounted on the end of the blade (102); A fan casing (6), wherein the fan casing (6) wraps the stator assembly (7) and the rotor assembly (5); An axial air gap (19) is formed between the stator assembly (7) and the rotor assembly (5), and the impeller (1) and the rotor assembly (5) have the freedom to rotate synchronously relative to the stator assembly (7).

2. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 1, characterized in that: The rotor magnetic steel (2) and the blades (102) are an integrated magnetic conductive component, or the rotor magnetic steel (2) and the blades (102) are independent components and are assembled together by fasteners.

3. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 1, characterized in that: The rotor magnetic steel (2) and the blade (102) are assembled with each other via a countersunk bolt (14), and the axis of the countersunk bolt (14) is parallel to the axis of the impeller (1).

4. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 1, characterized in that: In the cross-sectional direction of the impeller (1), the blades (102) and the rotor magnetic steel (2) have the same cross-sectional profile; The cross-sectional profile of the blade (102) or the rotor magnetic steel (2) is one of streamline, elliptical, and diamond shapes, or a combination thereof.

5. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 1, characterized in that: The stator assembly (7) comprises a stator core (9) and a winding (10), wherein the stator core (9) comprises a circular ring portion (901), an axial protrusion (902) is fixed to one axial end of the circular ring portion (901), a plurality of the axial protrusions (902) are arranged in a circular array around the axis of the stator assembly (7), and the winding (10) is wound around the side surface of the axial protrusion (902).

6. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 5, characterized in that: The axial extension direction of the axial protrusion (902) is parallel to the axial extension direction of the blade (102); The sum of the axial lengths of the blade (102) and the rotor magnetic steel (2) is greater than the axial length of the axial protrusion (902).

7. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 5, characterized in that: The number of the rotor magnetic steels (2) is not equal to the number of the axial protrusions.

8. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 1, characterized in that: The fan casing (6) comprises a main casing (3) and an end cover (4); The main housing (3) is provided with a cylindrical cavity (301) for accommodating the rotor assembly (5), and the main housing (3) further comprises an air inlet duct (302) and an air outlet duct (303) which are in communication with the cylindrical cavity (301), and the air inlet duct (302) and the air outlet duct (303) respectively extend in a direction perpendicular to the axis of the main housing (3); The end cover (4) is assembled with one end of the stator assembly (7).

9. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 8, characterized in that: The inner wall of the main housing (3) is protruded with a convex shaft (306), the convex shaft (306) and the annular plate (101) are movably assembled via a bearing (11), and the impeller (1) has a degree of freedom of rotation around the convex shaft (306).

10. The compressed air crossflow fan with an integrated structure of an impeller and a permanent magnet motor according to claim 9, characterized in that: The bearing (11) is coaxially arranged with an outer retaining ring (12) and an inner retaining ring (13); the outer retaining ring (12) and the inner retaining ring (13) are in contact with the same axial end of the bearing (11); the outer retaining ring (12) is in contact with the outer ring of the bearing (11) and the annular sheet (101); and the inner retaining ring (13) is in contact with the inner ring of the bearing (11) and the convex shaft (306).

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