Micro-thin efficient centrifugal fan and manufacturing method thereof

Abstract

The invention provides a micro-thin type efficient centrifugal fan and a manufacturing method thereof. The centrifugal fan comprises an impeller, a fan blade and a fan blade, the driving assembly is connected with the impeller and used for driving the impeller to rotate; the control assembly is connected with the driving assembly and used for controlling the driving assembly to drive the impeller to rotate; and the volute and volute cover assembly is used for accommodating the impeller, the driving assembly and the control assembly. According to the micro-thin efficient centrifugal fan and the manufacturing method thereof, on the premise that the requirement for the size of the centrifugal fan in the aerospace field is met, the connecting strength of the volute, the volute cover, the magnet yoke and the fan blades is high, the structural stability is good, high-efficiency operation of the centrifugal fan can be achieved under the same size, and the service life of the centrifugal fan is prolonged. And compared with a fan with the same size, higher air volume and air pressure can be provided.

Description

Technical Field

[0001] The invention relates to the field of fan equipment, and in particular to a micro-thin high-efficiency centrifugal fan and a manufacturing method thereof. Background Art

[0002] Centrifugal fans are based on the principle of converting kinetic energy into potential energy. They use high-speed rotating impellers to accelerate the gas, then decelerate and change the flow direction, so that the kinetic energy is converted into potential energy (pressure). Centrifugal fans are widely used, ranging from mine ventilation, boiler air supply and chemical processes to laptop computers, aerospace fields, air conditioning, etc.

[0003] In the process of implementing the prior art, the inventor discovered that:

[0004] There are many problems with centrifugal fans used in the aerospace field. Centrifugal fans are large in size, heavy in weight, low in speed, and high in power consumption. Moreover, most of them use oil-containing bearings, which generally have a short lifespan and poor resistance to high and low temperatures. The grease in oil-containing bearings is easy to evaporate at high temperatures and easy to solidify at low temperatures, which cannot meet specific uses. In addition, their fixing method is generally a retaining spring structure, which has basically zero resistance to vibration and impact. The material of the oil-containing bearing is copper alloy, which has poor resistance to salt spray.

[0005] Therefore, it is necessary to provide a technical solution for a centrifugal fan with a smaller size, good structural stability and higher efficiency to solve the problems of large size, low speed, high power consumption and poor structural stability of the centrifugal fan. Summary of the invention

[0006] The main technical problem solved by the present invention is to solve the problems of large size, low speed, high power consumption and poor structural stability of centrifugal fans. The present application embodiment provides a micro-thin and high-efficiency centrifugal fan, comprising:

[0007] impeller;

[0008] A driving assembly connected to the impeller and used to drive the impeller to rotate;

[0009] A control component connected to the driving component and used to control the driving component to drive the impeller to rotate;

[0010] The volute casing and cover assembly is used to accommodate the impeller, drive assembly, and control assembly.

[0011] Furthermore, the impeller specifically includes: an inner cylindrical shell; an outer ring; blades arranged between the inner cylindrical shell and the outer ring and distributed circumferentially along the axis of the inner cylindrical shell; an annular boss extending circumferentially outward at one end of the inner cylindrical shell, and the blades are connected to the annular boss of the inner cylindrical shell; the outer ring is located at the other end of the inner cylindrical shell; the blades are arc-shaped, and the radius of the arc on the inner side of the blade is lower than the radius of the arc on the outer side; the arc-shaped boss portion of the blade connected to the inner cylindrical shell is provided with an elliptical chamfer; the height of the blade connected to one end of the outer ring is lower than the height of the blade close to the other end of the inner cylindrical shell.

[0012] Furthermore, the drive assembly is provided, specifically comprising: a yoke connected to the inner cylindrical shell; a drive shaft located at the center of the yoke and connected to the yoke; a bearing assembly sleeved on the drive shaft; a magnetic steel located in the yoke and connected to the impeller; a stator assembly located between the magnetic steel and the bearing assembly; wherein the yoke comprises a circular bottom cover for the drive shaft to pass through and an annular side wall vertically connected to the side wall of the circular bottom cover, and an arc-shaped step hole is circumferentially opened at the connection position between the circular bottom cover and the annular side wall along the center line of the annular side wall; an annular protrusion is circumferentially provided at one end of the inner wall of the inner cylindrical shell for resisting the annular side wall of the yoke, and an arc-shaped block is also provided at the other end of the inner wall of the inner cylindrical shell corresponding to the position of the arc-shaped step hole, and the inner cylindrical shell is also provided with an annular tight side wall inside the annular side wall of the yoke, and the inner cylindrical shell is connected to the annular tight side wall through the arc-shaped block.

[0013] Furthermore, the bearing assembly specifically includes: a first ball bearing close to the circular bottom cover of the yoke; a second ball bearing connected to the first bearing; at least one spiral retaining ring connected to the end face of the second bearing; wherein a bearing gasket is also provided between the first ball bearing and the second ball bearing.

[0014] Furthermore, the stator assembly specifically includes:

[0015] Hall chip circuit board;

[0016] The four-level single-phase stator coil connected to the Hall chip circuit board is used to drive the rotation of the magnetic steel.

[0017] Furthermore, the control component controls the Hall chip circuit board of the driving component through a control chip, and the control chip is a CC6420 chip.

[0018] Furthermore, the volute and volute cover assembly specifically includes: a volute and a volute cover, the volute is provided with an annular accommodating cavity between the stator assembly and the bearing assembly, and is recessed in the direction of the impeller position; a accommodating hole for the drive shaft to pass through is provided at the bottom of the annular accommodating cavity; a locking threaded hole for locking with a locking bolt is provided on the end face of the drive shaft close to the second bearing; an annular groove is also axially provided on the side wall of the annular accommodating cavity for accommodating the spiral retaining ring; the locking screw is used to limit the displacement of the inner ring of the second bearing; and the spiral retaining ring is used to limit the displacement of the inner ring of the second bearing.

[0019] Furthermore, the volute cover is provided with an air guide hole at a position corresponding to the impeller;

[0020] The volute cover is connected to the volute casing by a plurality of bolts, and the volute cover is provided with a countersunk hole for the bolt head to be flush with the end surface of the volute cover.

[0021] Furthermore, the volute and volute cover assembly also includes a mounting base, the volute is circumferentially provided with a plurality of connecting hole bosses, the connecting hole bosses are provided with connecting holes, the mounting base is provided with connecting columns at positions corresponding to the connecting holes, the connecting columns are provided with mounting holes corresponding to the connecting holes, the connecting hole bosses are provided between the upper and lower end faces of the volute, and the volute is connected to the mounting base by means of hexagonal screws connected to the connecting holes of the volute and the mounting holes of the mounting base.

[0022] In addition, the present application also provides a method for manufacturing a micro-thin and efficient centrifuge, comprising the following steps: welding a drive shaft to the center position of a magnetic yoke; placing the welded magnetic yoke with a drive shaft into an impeller injection mold to injection mold an impeller; pressing the magnetic steel into the injection-molded impeller to form an injection-molded impeller with magnetic steel; installing the stator assembly and the injection-molded impeller with magnetic steel on a volute; installing the bearing assembly in the accommodating cavity of the volute and locking it with a locking screw and a spiral retaining ring; connecting the volute cover to the volute with bolts, and connecting it to the connecting hole of the volute and the mounting hole of the mounting base with a hexagonal screw to complete the manufacture of the centrifugal fan; wherein the height of the hexagonal screw relative to the end face of the mounting base is lower than the height of the end face of the volute cover facing away from the volute relative to the end face of the mounting base

[0023] The embodiments provided in the present application have at least the following beneficial effects: through the thin and efficient centrifugal fan and the manufacturing method thereof provided in the present application, it can be ensured that, under the premise of meeting the volume requirements of centrifugal fans in the aerospace field, the connection strength of the volute, volute cover, yoke and fan blades is high, the structural stability is good, and the centrifugal fan can operate with higher efficiency under the same size, that is, it can provide higher air volume and air pressure compared with fans of the same volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0025] Figure 1 A schematic diagram of the structure of a centrifugal fan provided in an embodiment of the present application.

[0026] Figure 2 Another schematic diagram of the structure of a centrifugal fan provided in an embodiment of the present application.

[0027] Figure 3 for Figure 2 A schematic structural diagram of the AA cross section of a centrifugal fan provided in an embodiment of the present application.

[0028] Figure 4 A schematic diagram of the structure of an impeller provided in an embodiment of the present application.

[0029] Figure 5 A schematic diagram of the yoke structure provided in an embodiment of the present application.

[0030] Figure 6 A schematic diagram of the partial structure of the centrifugal fan provided in an embodiment of the present application.

[0031] Figure 7 A schematic diagram of the volute structure provided in an embodiment of the present application.

[0032] Figure 8 This is a schematic diagram of the principle structure of the driver chip circuit provided in an embodiment of the present application.

[0033] Fig. 9 A schematic flow chart of a method for manufacturing a micro-thin and efficient centrifuge provided in an embodiment of the present application.

[0034] Reference numerals:

[0035] 100. Thin and efficient centrifugal fan;

[0036] 10. impeller; 11. inner cylindrical shell; 111. annular boss; 112. annular convex block; 113. arc block; 114. annular close side wall; 12. outer ring; 13. blades;

[0037] 20. Driving assembly; 21. Magnetic yoke; 210. Circular bottom cover; 211. Annular side wall; 212. Arc-shaped step hole; 22. Driving shaft; 221. Locking threaded hole; 23. Bearing assembly; 231. First ball bearing; 232. Second ball bearing; 233. Spiral retaining ring; 234. Bearing gasket; 24. Magnetic steel 24; 25. Stator assembly; 251. Hall chip circuit board; 252. Four-stage single-phase stator coil;

[0038] 30. Control components;

[0039] 40. Volute and volute cover assembly;

[0040] 41, volute; 411, annular accommodating chamber; 412, annular groove; 413, accommodating hole; 414, connecting hole boss; 415, connecting hole;

[0041] 42. Snail cover; 421. Air guide hole;

[0042] 43. Mounting base; 433. Connecting column; 435. Hexagon screw. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0044] Please refer to Figures 1 to 3 The present application discloses a micro-thin and efficient centrifugal fan 100, comprising: an impeller 10; a driving assembly 20 connected to the impeller 10 for driving the impeller 10 to rotate; a control assembly 30 connected to the driving assembly 20 for controlling the driving assembly 20 to drive the impeller 10 to rotate; and a volute and cover assembly 40 for accommodating the impeller 10, the driving assembly 20, and the control assembly 30.

[0045] The present application provides a thin and efficient centrifugal fan 100 which is mainly used in the aerospace field. That is, the centrifugal fans used in the aerospace field in the prior art occupy a large space, are heavy, have a low speed and high power consumption, and the centrifugal fans have a poor structural design, resulting in a short lifespan. Based on the above problems, the present application provides an improved centrifugal fan to solve the above problems.

[0046] The impeller 10 in the present application is made of PA66+30GF, that is, glass fiber reinforced nylon 66. The structure of the impeller 10 includes: an inner cylindrical shell 11; an outer ring 12; blades 13 arranged between the inner cylindrical shell 11 and the outer ring 12 and distributed circumferentially along the axis of the inner cylindrical shell 11; an annular boss 111 is extended circumferentially outward at one end of the inner cylindrical shell 11, and the blades 13 are connected to the annular boss 111 of the inner cylindrical shell 11; the outer ring 12 is located at the other end of the inner cylindrical shell 11; the blades 13 are arc-shaped, and the radius of the arc inside the blades 13 is lower than the radius of the arc outside; the arc-shaped boss part of the blades 13 connected to the inner cylindrical shell 11 is provided with an elliptical chamfer; the height of the blade 13 connected to one end of the outer ring 12 is lower than the height of the blade 13 close to the other end of the inner cylindrical shell 11.

[0047] Specifically, Figure 4 As shown, in the present application, the blades 13 of the impeller 10 are fixed by the annular boss 111 extending from the outer wall of one end of the inner cylindrical shell 11 and the outer ring 12. It can be understood that in order to enhance the working strength of the blades 13 of the impeller 10, the deformation of the blades 13 during high-speed operation can be reduced by setting the outer ring 12. The blades 13 are arc-shaped and the radius of the inner arc is lower than the radius of the outer arc, so that the blades 13 of the impeller 10 can have better exhaust capacity. The elliptical chamfer of the blade 13 is set to prevent stress concentration at the root of the blade 13 and cause fracture. In addition, the height of the blade 13 connected to the outer ring 12 is designed to be lower than the height of the other end of the blade 13 close to the inner cylindrical shell 11, which can increase a part of the air volume and pressure and improve the efficiency of the fan.

[0048] It can be seen that in order to solve the problems of poor structural stability and low efficiency of centrifugal fans and meet the volume requirements of centrifugal fans in the aerospace field, the present application improves the structure of the impeller 10 to improve the structural stability of the centrifugal fan, the low efficiency and meet the volume requirements of the centrifugal fan in the aerospace field. In a preferred embodiment provided by the present application, the inner radius of the arc of the blade 13 is 3mm, the outer radius arc is 3.5mm, the thickness of the blade 13 is 0.38mm, and the height is 7mm. The outer diameter of the outer ring 12 is 33.1mm, the inner diameter is 31.5mm, and the thickness is 0.8mm. The elliptical chamfer has a radius of 0.3mm and a height of 5mm. The height of the blade 13 connecting one end of the outer ring 12 is lower than the height of the other end of the blade 13 close to the inner cylindrical shell 11. Specifically, it can be realized by setting a small boss at the position of the blade 13 close to the cylindrical shell, and of course it can also be designed as a ramp-shaped structure. The design here can make the impeller 10 height not exceed the volute cover 42, and realize the increase of part of the air volume and pressure, thereby improving the efficiency of the fan.

[0049] Furthermore, the driving assembly 20 specifically includes: a yoke 21 connected to the inner cylindrical shell 11; a driving shaft 22 located at the center of the yoke 21 and connected to the yoke 21; a bearing assembly 23 sleeved on the driving shaft 22; a magnetic steel 24 located in the yoke 21 and connected to the impeller 10; a stator assembly 25 located between the magnetic steel 24 and the bearing assembly 23; wherein the yoke 21 includes a circular bottom cover 210 for the driving shaft 22 to pass through and an annular side wall 211 vertically connected to the side wall of the circular bottom cover 210, An arc-shaped step hole 212 is circumferentially provided at the connection position between the cover 210 and the annular side wall 211 along the center line of the annular side wall 211; an annular protrusion 112 is circumferentially provided at one end of the inner wall of the inner cylindrical shell 11 for resisting the annular side wall 211 of the yoke 21, and an arc-shaped block 113 is provided at the other end of the inner wall of the inner cylindrical shell 11 corresponding to the position of the arc-shaped step hole 212; the inner cylindrical shell 11 is also provided with an annular close-fitting side wall 114 inside the annular side wall 211 of the yoke 21, and the inner cylindrical shell 11 is connected to the annular close-fitting side wall 114 through the arc-shaped block 113.

[0050] Specifically, Figure 5 As shown, a center hole for inserting the drive shaft 22 is provided in the center of the yoke 21, and the yoke 21 and the drive shaft 22 are laser welded to ensure the connection strength and concentricity. An annular protrusion 112 is provided at one end of the inner wall of the inner cylindrical shell 11 to connect with the annular side wall 211 of the yoke 21, so as to ensure the connection strength between the impeller 10 and the yoke 21. The other end of the inner wall of the inner cylindrical shell 11 is connected to the annular side wall 211 by an arc block 113 and an annular close-fitting side wall 114 connected to the arc block 113 and used to close the annular side wall 211, so as to achieve a stable connection between the structure of the yoke 21 and the impeller 10. In a preferred embodiment provided in the present application, the yoke 21 is provided with 6 arc-shaped step holes 212 in the circumferential direction, the center of the arc is located outside the annular side wall 211 of the yoke 21, the diameter of the arc is 2 mm, and the depth of the step hole is 1 mm. After the drive shaft 22 is welded to the yoke 21, it is placed inside the mold of the injection-molded impeller 10, and the injection-molded plastic passes through the arc-shaped step hole 212 of the yoke 21 to form the arc-shaped block 113 and the annular close-fitting side wall 114 connected to the arc-shaped block 113. It can be seen that the arc-shaped block 113 of the cylindrical housing 11 of the yoke 21 and the annular close-fitting side wall 114 connected to the arc-shaped block 113 form an interlocking circle, thereby preventing the fan blade from falling off.

[0051] After the impeller 10 with the drive shaft 22 and the yoke 21 is formed, the magnetic steel 24 is pressed into the inner wall of the cylindrical shell 11 of the impeller 10, and one end of the magnetic steel 24 is connected to one end of the annular close-fitting side wall 114. Thus, the magnetic steel 24 located in the yoke 21 and connected to the impeller 10 is formed.

[0052] like Figure 6As shown, the stator assembly 25 includes: a Hall chip circuit board 251; and a four-level single-phase stator coil 252 connected to the Hall chip circuit board 251, which is used to drive the rotation of the magnetic steel 24.

[0053] Specifically, the Hall chip circuit board 251 can sense the position of the magnet 24 and generate magnetic fields of different polarities by switching the power-on sequence of the stator coils, thereby driving the magnet 24 inside the impeller 10 to transmit.

[0054] Furthermore, the bearing assembly 23 includes a first ball bearing 231 close to the circular bottom cover 210 of the yoke 21; a second ball bearing 232 connected to the first bearing; and at least one spiral retaining ring 233 connected to the end face of the second bearing; wherein a bearing gasket 234 is also provided between the first ball bearing 231 and the second ball bearing 232.

[0055] Specifically, the bearing support is controlled by the bearing gasket 234 to prevent the inner ring and the outer ring of the bearing from falling out.

[0056] It should be noted that the bearing assembly 23 is sleeved on the drive shaft 22 and is also located in the annular accommodating chamber 411 provided in the volute 41. The accommodating chamber of the volute 41 is used to accommodate the first ball bearing 231, the second ball bearing 232, the bearing gasket 234, and the spiral retaining ring 233. An annular groove 412 is provided in the volute 41 to accommodate the spiral retaining ring 233, thereby preventing the outer ring of the second bearing from falling out. In a preferred embodiment provided in the present application, the spiral retaining ring 233 is fixed in the annular groove 412 using an EK-8 double-layer spiral retaining ring 233.

[0057] It should also be pointed out that this structure allows the bearing assembly 23 to be installed from the same side, which can ensure a higher concentricity, improve the operating accuracy, and is suitable for the transmission of thin fans.

[0058] Furthermore, the control component 30 controls the Hall chip circuit board 251 of the driving component 20 through a control chip, and the control chip is a CC6420 chip.

[0059] Specifically, Figure 8 As shown, the CC6420 chip integrates PWM speed regulation function, FG speed detection function, and a wider power supply range, the power supply range is 3.5V ~ 22V, the drive current can reach up to 450mA, and the temperature resistance is -40 ~ 125℃. At the same time, TVS tubes are added to the peripheral circuit to prevent surge damage, and several filter capacitors are added to improve the electromagnetic compatibility performance of the fan.

[0060] Furthermore, the volute and volute cover assembly 40 includes a volute 41 and a volute cover 42. Figure 7As shown, the volute 41 is recessed between the stator assembly 25 and the bearing assembly 23 toward the position of the impeller 10 to provide an annular accommodating chamber 411, the bottom of the annular accommodating chamber 411 is provided with an accommodating hole 413 for the drive shaft 22 to pass through, the end surface of the drive shaft 22 close to the second bearing is provided with a locking threaded hole 221 for locking with a locking bolt, an annular groove 412 is also axially provided on the side wall of the annular accommodating chamber 411 to accommodate the spiral retaining ring 233, the locking bolt is used to limit the displacement of the inner ring of the second bearing, and the spiral retaining ring 233 is used to limit the displacement of the inner ring of the second bearing, and the volute 41 and the volute cover 42 are both made of 7075 aluminum alloy.

[0061] Specifically, the locking screw not only locks the drive shaft 22 through the locking threaded hole 221, but also locks the inner ring of the second bearing through the end of the locking bolt. The volute cover assembly 40 is mainly used to accommodate the impeller 10, the drive assembly 20 and the control assembly 30. The volute cover assembly 40 is made of 7075 aluminum alloy, which has the advantages of vibration resistance and impact resistance.

[0062] Furthermore, the volute cover 42 is provided with an air guide hole 421 at a position corresponding to the impeller 10 ; the volute cover 42 is connected to the volute casing 41 by a plurality of bolts, and the volute cover 42 is provided with a countersunk hole for the bolt head to be flush with the end face of the volute cover 42 .

[0063] Specifically, the air guide hole 421 can increase the air intake. The volute cover 42 and the volute 41 are fixed by bolting the volute cover 42 and the volute 41. The volute cover 42 is provided with a countersunk hole for the bolt head to be flush with the end face of the volute cover 42, so that after the bolt is locked, the screw head will not exceed the plane of the volute 41, further reducing the size. In a preferred embodiment provided in the present application, when the bolt is inserted into the countersunk hole to lock the volute cover 42 and the volute 41, thread glue is applied to the bolt to prevent the screw from loosening during vibration.

[0064] In a preferred embodiment provided in the present application, the volute cover 42 has a thickness of 1 mm, a countersunk hole diameter of 2.8 mm, a depth of 0.55 mm, a bare double head diameter of 2.5 mm, and a head thickness of 0.5 mm.

[0065] Furthermore, the volute and volute cover assembly 40 also includes a mounting base 43, the volute 41 is circumferentially provided with a plurality of connecting hole bosses 414, the connecting hole bosses 414 are provided with connecting holes 415, the mounting base 43 is provided with connecting columns 433 at positions corresponding to the connecting holes 415, the connecting columns 433 are provided with mounting holes (not shown in the figure) corresponding to the connecting holes 415, the connecting hole bosses 414 are provided between the upper and lower end surfaces of the volute 41, and the volute 41 is connected to the mounting base 43 by hexagonal screws 435 connected to the connecting holes 415 of the volute 41 and the mounting holes of the mounting base 43.

[0066] Specifically, the connection hole boss 414 is located between the upper and lower end surfaces of the volute 41, and the volute 41 and the mounting hole of the mounting base 43 are connected by the hexagonal screw 435. It can be understood that after being locked by the hexagonal screw 435, the head of the hexagonal screw 435 can be lower than the upper end surface of the volute cover 42. It can also be understood that the mounting hole of the mounting base 43 is set at the position where the centrifugal fan needs to be installed, so that the volute 41 can be directly installed through the mounting hole, thereby saving the installation thickness.

[0067] In a preferred embodiment provided by the present application, the thickness of the volute 41 is 9mm, the diameter of the connection hole 415 of the four connection hole bosses 414 is 2.8mm, the height from the flange plane of the connection hole 415 to the bottom plane of the volute 41 is 4mm, and the height of the connection column 433 is 4mm, or in other words, four connection columns 433 and connection holes 415 are arranged at the position where the centrifugal fan needs to be installed, which has the advantage of saving the installation thickness during installation. At the same time, the flange of the connection hole 415 is 2.5mm away from the upper plane of the volute 41, and after adding the volute cover 42, the distance is 3.5mm, and the thickness of the head of the hexagon socket head cap screw is only 2.5mm, which is 1mm lower than the volute cover after locking, so that the thickness after locking does not exceed the thickness of the fan.

[0068] Furthermore, a lead-out groove is provided on the back of the volute 41 for installing power cables and signal cables. In a preferred embodiment provided in the present application, the lead-out groove has a depth of 0.55 mm and a width of 4 mm. The lead-out wire is a PFA insulated ultra-flexible wire with a temperature range of -60 to 250°C and a cross-sectional area of ​​0.035 mm. 2 The outer diameter of the wire is 0.45mm, and it can provide 4 lead wires. The functions of the lead wires are positive (red), negative (black), PWM speed regulation (blue), and speed signal output (white).

[0069] Furthermore, when the stator assembly 25 and the control assembly 30 are installed in the volute cover 42 , thermal conductive glue is applied to corresponding positions to help the Hall chip circuit board 251 and the control chip in the stator assembly 25 and the control assembly 30 to dissipate heat quickly.

[0070] Furthermore, a fan-shaped avoidance area for the stator pin welding points is provided on the back of the volute 41 to prevent the welding points from contacting the metal casing and causing a short circuit.

[0071] In addition, if Fig. 9 As shown, the present application also provides a method for manufacturing a thin and efficient centrifuge, comprising the following steps:

[0072] S100: Welding the drive shaft 22 to the center of the yoke 21;

[0073] S110: placing the welded yoke 21 with the driving shaft 22 into an injection mold of the impeller 10 to injection mold the impeller 10;

[0074] S120: Pressing the magnetic steel 24 into the injection-molded impeller 10 to form an injection-molded impeller 10 having the magnetic steel 24;

[0075] S130: Installing the stator assembly 25 and the injection-molded impeller 10 having the magnetic steel 24 on the volute 41;

[0076] S140: Install the bearing assembly 23 in the accommodating cavity of the volute 41 and lock it by means of locking screws and spiral retaining ring 233;

[0077] S150: The volute cover 42 is connected to the volute 41 by bolts, and is connected to the connection hole of the volute 41 and the mounting hole of the mounting base 43 by hexagonal screws 435, thereby completing the manufacture of the centrifugal fan.

[0078] The height of the hexagonal screw 435 relative to the end surface of the mounting base 43 is lower than the height of the end surface of the volute cover 42 facing away from the volute 41 relative to the end surface of the mounting base 43 .

[0079] It should also be pointed out that the actual size of the centrifugal fan provided in the present application is 45mmX45mmX10mm, the air volume can reach 8.8㎡ / h during operation, the weight of the whole machine is 40g, and the volute 41 and the volute cover 42 are made of 7075 aviation aluminum alloy. Compared with the previous centrifugal fans, there is no micro-thin centrifugal fan of this size, and under the premise of this size, the stability of the internal structure of the centrifugal fan and the high efficiency operation are guaranteed.

[0080] It is to be understood that the embodiments described in this application are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0081] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0082] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0083] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A thin and efficient centrifugal fan, characterized in that: include: impeller; A driving assembly connected to the impeller and used to drive the impeller to rotate; A control component connected to the driving component and used to control the driving component to drive the impeller to rotate; The volute casing and cover assembly is used to accommodate the impeller, drive assembly, and control assembly.

2. The micro-thin high-efficiency centrifugal fan according to claim 1, characterized in that: The impeller specifically comprises: inner cylindrical shell; Outer ring; Blades are arranged between the inner cylindrical shell and the outer ring and are distributed circumferentially along the axis of the inner cylindrical shell; An annular boss is circumferentially extended outward at one end of the inner cylindrical shell, and the blade is connected to the annular boss of the inner cylindrical shell; The outer ring is located at the other end of the inner cylindrical shell; The blade is in an arc shape, and the radius of the arc on the inner side of the blade is lower than the radius of the arc on the outer side; The arc-shaped boss portion where the blade is connected to the inner cylindrical shell is provided with an elliptical chamfer; The height of one end of the blade connected to the outer ring is lower than the height of the other end of the blade close to the inner cylindrical shell.

3. The micro-thin high-efficiency centrifugal fan according to claim 2, characterized in that: The driving component specifically comprises: a magnetic yoke connected to the inner cylindrical shell; A drive shaft located at the center of the yoke and connected to the yoke; A bearing assembly sleeved on the drive shaft; A magnetic steel located in the magnetic yoke and connected to the impeller; a stator assembly located between the magnetic steel and the bearing assembly; The yoke comprises a circular bottom cover for the driving shaft to pass through and an annular side wall vertically connected to the side wall of the circular bottom cover, and an arc-shaped step hole is opened at the connection position between the circular bottom cover and the annular side wall along the circumferential direction of the center line of the annular side wall; One end of the inner wall of the inner cylindrical shell is circumferentially provided with an annular protrusion for resisting the annular side wall of the yoke, and the other end of the inner wall of the inner cylindrical shell is provided with an arc block corresponding to the position of the arc step hole. The inner cylindrical shell is also provided with an annular close-fitting side wall inside the annular side wall of the yoke, and the inner cylindrical shell is connected to the annular close-fitting side wall through the arc block.

4. The micro-thin high-efficiency centrifugal fan according to claim 3, characterized in that: The bearing assembly specifically comprises: a first ball bearing adjacent to the circular bottom cover of the yoke; a second ball bearing connected to the first bearing; at least one spiral retaining ring connected to the second bearing end surface; Wherein, a bearing gasket is further provided between the first ball bearing and the second ball bearing.

5. The micro-thin high-efficiency centrifugal fan according to claim 3, characterized in that: The stator assembly specifically comprises: Hall chip circuit board; The four-level single-phase stator coil connected to the Hall chip circuit board is used to drive the rotation of the magnetic steel.

6. The micro-thin high-efficiency centrifugal fan according to claim 5, characterized in that: The control component controls the Hall chip circuit board of the driving component through the control chip, and the control chip is a CC6420 chip.

7. The micro-thin high-efficiency centrifugal fan according to claim 3, characterized in that: The volute and volute cover assembly specifically includes: a volute and a volute cover, the volute is recessed between the stator assembly and the bearing assembly toward the impeller position to form an annular accommodating cavity, the bottom of the annular accommodating cavity is provided with an accommodating hole for the drive shaft to pass through, the end surface of the drive shaft close to the second bearing is provided with a locking threaded hole for locking with a locking bolt, an annular groove is also axially provided on the side wall of the annular accommodating cavity to accommodate the spiral retaining ring, the locking bolt is used to limit the displacement of the inner ring of the second bearing, and the spiral retaining ring is used to limit the displacement of the inner ring of the second bearing, and the volute and volute cover are both made of 7075 aluminum alloy.

8. The micro-thin high-efficiency centrifugal fan according to claim 7, characterized in that: The volute cover is provided with an air guide hole at a position corresponding to the impeller; The volute cover is connected to the volute casing by a plurality of bolts, and the volute cover is provided with a countersunk hole for the bolt head to be flush with the end surface of the volute cover.

9. The micro-thin high-efficiency centrifugal fan according to claim 8, characterized in that: The volute and volute cover assembly also includes a mounting base, a plurality of connecting hole bosses are arranged circumferentially of the volute, the connecting hole bosses are provided with connecting holes, connecting columns are provided at positions corresponding to the connecting holes of the mounting base, mounting holes are provided on the connecting columns corresponding to the connecting holes, the connecting hole bosses are arranged between the upper and lower end faces of the volute, and the volute is connected to the mounting base by hexagonal screws connected to the connecting holes of the volute and the mounting holes of the mounting base.

10. A method for manufacturing a micro-thin high-efficiency centrifuge according to any one of claims 1 to 9, characterized in that: The following steps are involved: Weld the drive shaft to the center of the yoke; Putting the welded magnetic yoke with the driving shaft into an impeller injection mold to injection mold the impeller; Pressing the magnetic steel into the injection-molded impeller to form an injection-molded impeller having the magnetic steel; Mounting the stator assembly and the injection molded impeller with magnetic steel to the volute; Install the bearing assembly in the accommodating cavity of the volute and lock it with locking screws and spiral retaining rings; The volute cover is connected to the volute by bolts, and is connected to the connection hole of the volute and the mounting hole of the mounting base by hexagonal screws, thereby completing the manufacture of the centrifugal fan; The height of the hexagonal screw relative to the end face of the mounting base is lower than the height of the end face of the volute cover facing away from the volute casing relative to the end face of the mounting base.

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