Air guide ring, axial flow fan and air conditioner

Abstract

The application relates to the technical field of axial flow fans, in particular to a guide ring, an axial flow fan and an air conditioner, which are applied to the axial flow fan; the guide ring comprises a guide cylinder and an embedded ring body; the inner surface of the guide cylinder is sequentially provided with a first guide ring and a second guide ring in the air outlet direction; a connecting portion is arranged between the first guide ring and the second guide ring; the inner diameter of the first guide ring is smaller than that of the second guide ring; the first guide ring and the second guide ring correspond to the suction surface and the pressure surface of the axial flow fan blade respectively; the embedded ring body is located in the second guide ring and is adjacent to the first guide ring; the inner diameter of the embedded ring body is larger than that of the first guide ring; the gap between the embedded ring body, the second guide ring and the connecting portion forms a non-return flow channel; the guide ring can effectively solve the problem of leakage loss of the axial flow fan under the high static pressure working condition while ensuring that the axial flow fan has sufficient safety tip radial clearance.

Description

Technical Field

[0001] This application relates to the field of axial flow fan technology, and in particular to an air guide ring, an axial flow fan and an air conditioner. Background Technology

[0002] Axial flow fans operate by passing air along the impeller shaft axially, characterized by low pressure and high flow rate. They are widely used for cooling and ventilation in air conditioning equipment and household appliances. A typical axial flow fan consists of a guide vane and axial blades housed within it. To ensure proper operation, a reasonable radial clearance at the blade tips is required between the blades and the guide vane. This radial clearance significantly impacts the fan's head, efficiency, and noise performance. During operation, a large pressure difference exists between the pressure and suction surfaces of the axial flow fan blades. Excessive radial clearance at the blade tips can cause backflow along this clearance, resulting in leakage losses and reduced efficiency. Conversely, insufficient radial clearance, while mitigating leakage, can lead to blade breakage under unstable operating conditions such as foreign object embedding, or freezing of the blades and guide vane at low temperatures, rendering the fan inoperable. Summary of the Invention

[0003] The purpose of this application is to provide an air guide ring, an axial flow fan, and an air conditioner. The air guide ring can effectively solve the problem of leakage loss of the axial flow fan tip radial clearance under high static pressure conditions while ensuring that the axial flow fan has a sufficiently safe blade tip radial clearance.

[0004] Therefore, in a first aspect, embodiments of this application provide an air guide ring for use in an axial flow fan; the air guide ring includes: an air guide tube, on the inner surface of which a first air guide ring and a second air guide ring are sequentially arranged along the air outlet direction, a connecting portion is provided between the first air guide ring and the second air guide ring, the inner diameter of the first air guide ring is smaller than the inner diameter of the second air guide ring, the first air guide ring and the second air guide ring correspond to the suction surface and pressure surface of the axial flow fan blades in the axial flow fan, respectively; and an embedded ring body, which is located inside the second air guide ring and adjacent to the first air guide ring, the inner diameter of the embedded ring body is larger than the inner diameter of the first air guide ring, and the gap between the embedded ring body, the second air guide ring and the connecting portion forms a check flow channel.

[0005] In one possible implementation, the connecting part has a groove on the side facing the inner ring, and the end of the inner ring facing the groove has an arc surface. The arc surface and the groove form a check section of the check flow channel, which is used to change the direction of the leaking airflow.

[0006] In one possible implementation, the embedded ring also includes a first face facing the check channel, the first face being connected to one end of the arc surface, and a leakage section of the check channel being formed between the first face and the second air guide ring, the leakage section being used to guide the leaked airflow to the check section.

[0007] In one possible implementation, the embedded ring also includes a second surface away from the check channel, one end of which is connected to the end of the arc surface away from the first surface.

[0008] In one possible implementation, the end of the second surface away from the arc surface is connected to the end of the first surface away from the arc surface. The first surface is parallel to the axis of the air guide tube. The second surface and the first surface form an angle γ, which satisfies the following condition: 10°≤γ≤20°.

[0009] In one possible implementation, the connecting part is provided with a positioning slot, and the end of the embedded ring facing the connecting part is provided with a first positioning block, which is inserted into the positioning slot.

[0010] In one possible implementation, the outer surface of the embedded ring is provided with a plurality of second positioning blocks along the circumferential direction. The plurality of second positioning blocks abut against the inner surface of the second air guide ring. The air guide ring also includes fasteners provided on the air guide tube, and the fasteners are connected to the second positioning blocks.

[0011] In one possible implementation, the air duct also includes an air inlet ring disposed at the input end of the first air guide ring, the first air guide ring being gradually expanded along the direction from the second air guide ring to the air inlet ring.

[0012] In one possible implementation, the air duct also includes an air outlet ring disposed at the output end of the second air guide ring, the air outlet ring being gradually expanded along the air outlet direction.

[0013] In one possible implementation, the distance between the first guide ring and the tip of the axial flow fan blade is the tip radial clearance c, and the width of the check channel is h. c and h satisfy the following relationship: h = 0.5 * c ~ c.

[0014] In one possible implementation, the distance between the first air guide ring and the tip of the axial flow fan blade is the tip radial clearance c, and the radius of the arc surface is f. c and f satisfy the following relationship: f = 0.8*c ~ 1.2*c.

[0015] In one possible implementation, the axial length of the second air guide ring is d, and the length of the second surface of the embedded ring along the axial direction of the air guide tube is e. d and e satisfy the following relationship: e = 0.5*d ~ 0.8*d.

[0016] Secondly, this application provides an axial flow fan, including: the aforementioned air guide ring; and axial flow blades disposed within the air guide tube of the air guide ring, wherein the suction surface and pressure surface of the axial flow blades correspond to the first air guide ring and the second air guide ring, respectively.

[0017] Thirdly, embodiments of this application provide an air conditioner including the aforementioned axial flow fan.

[0018] According to the air guide ring, axial flow fan, and air conditioner provided in the embodiments of this application, the air guide ring drives the air in the air guide tube to flow axially through the axial flow fan blades. A radial gap is formed between the axial flow fan blades and the air guide tube. There is a pressure difference between the pressure surface and the suction surface of the axial flow fan blades, which causes part of the airflow to leak through the radial gap. The leaked air is re-integrated into the airflow in the air guide tube through the check flow channel between the embedded ring and the air guide tube. This can effectively solve the problem of leakage loss of the radial gap at the blade tip of the axial flow fan under high static pressure conditions, and at the same time ensure that the axial flow fan has a sufficiently wide radial gap at the blade tip, thus improving safety. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0022] Figure 1 This diagram illustrates a three-dimensional structure of an air guide ring provided in an embodiment of this application.

[0023] Figure 2 This diagram shows a cross-sectional view of an air guide duct, an embedded ring, and a check flow channel provided in an embodiment of this application.

[0024] Figure 3 This illustration shows a cross-sectional structural diagram of an air guide duct and an embedded ring provided in an embodiment of this application.

[0025] Figure 4 This illustration shows a three-dimensional structural diagram of an embedded ring provided in an embodiment of this application;

[0026] Figure 5 This illustration shows a three-dimensional structural diagram of an air guide duct provided in an embodiment of this application;

[0027] Figure 6 Show Figure 5 A partially enlarged structural diagram of point A of the air duct shown;

[0028] Figure 7 This illustration shows a schematic diagram of the profile cross-sectional structure of a check flow channel according to an embodiment of this application;

[0029] Figure 8 This diagram illustrates the effect of a check channel in preventing airflow back according to an embodiment of this application.

[0030] Figure 9 This diagram shows a three-dimensional structural schematic of an axial flow fan provided in an embodiment of this application.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Air guide duct; 11. First air guide ring; 12. Second air guide ring; 121. Positioning groove; 122. Supporting step; 123. Perforation; 13. Connecting part; 131. Groove; 132. Positioning slot; 14. Air inlet ring; 15. Air outlet ring;

[0033] 2. Embedded ring; 21. Arc surface; 22. First surface; 23. Second surface; 24. First positioning block; 25. Second positioning block;

[0034] 3. Check flow path; 31. Check section; 32. Leakage section;

[0035] 4. Fasteners; 5. Axial fan blades; 6. Fan mounting panel; 7. Motor bracket; 8. Motor; 9. Fan guard. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] The following disclosure provides many different embodiments or examples for implementing different structures of the embodiments of this application. To simplify the disclosure of the embodiments of this application, components and arrangements of specific examples are described below. Of course, these are merely examples and are not intended to limit the embodiments of this application. Furthermore, reference numerals and / or letters may be repeated in different examples of the embodiments of this application. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0038] For ease of description, spatial relative terms may be used in the text to describe the relative position or movement of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "front," "back," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure undergoes a positional flip, orientation change, or change of motion, these directional indications will change accordingly. For instance, an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0039] To address the problems in the prior art, this application provides an air guide ring that can effectively solve the problem of leakage loss in the radial clearance of the blade tip of the axial flow fan under high static pressure conditions, while ensuring that the axial flow fan has a sufficiently safe radial clearance at the blade tip.

[0040] Figure 1 This diagram illustrates a three-dimensional structure of an air guide ring provided in an embodiment of this application. Figure 2 This diagram shows a cross-sectional view of an air guide duct, an embedded ring, and a check flow channel provided in an embodiment of this application. Figure 3 This illustration shows a cross-sectional structural diagram of an air guide duct and an embedded ring provided in an embodiment of this application. Figure 4 This illustration shows a three-dimensional structural diagram of an embedded ring provided in an embodiment of this application; Figure 5 This illustration shows a three-dimensional structural diagram of an air guide duct provided in an embodiment of this application; Figure 6 Show Figure 5 A partially enlarged structural diagram of point A of the air duct shown; Figure 7 This illustration shows a schematic diagram of the profile cross-sectional structure of a check flow channel according to an embodiment of this application; Figure 8This diagram illustrates the effect of a check channel in preventing airflow back, as provided in an embodiment of this application.

[0041] like Figure 1-8 As shown in the embodiment of this application, an air guide ring is provided and applied to an axial flow fan; the air guide ring includes: an air guide tube 1 and an inner ring 2.

[0042] The inner surface of the air guide duct 1 is provided with a first air guide ring 11 and a second air guide ring 12 in sequence along the air outlet direction. A connecting part 13 is provided between the first air guide ring 11 and the second air guide ring 12. The inner diameter of the first air guide ring 11 is smaller than the inner diameter of the second air guide ring 12. The first air guide ring 11 and the second air guide ring 12 correspond to the suction surface and pressure surface of the axial flow fan blade 5 inside the axial flow fan, respectively.

[0043] The embedded ring 2 is located inside the second air guide ring 12 and adjacent to the first air guide ring 11. The inner diameter of the embedded ring 2 is larger than the inner diameter of the first air guide ring 11. The gap between the embedded ring 2, the second air guide ring 12 and the connecting part 13 forms a check flow channel 3.

[0044] In this application, the axial flow fan 5 drives the air inside the air guide duct 1 to flow axially. A radial gap is formed between the axial flow fan 5 and the air guide duct 1. There is a pressure difference between the pressure surface and the suction surface of the axial flow fan 5, causing some airflow to leak through the radial gap. The airflow inside the air guide duct 1 has a certain centrifugal force under the drive of the axial flow fan 5. The inner diameter of the first air guide ring 11 is smaller than the inner diameter of the second air guide ring 12, causing the airflow to diffuse as it flows from the first air guide ring 11 to the second air guide ring 12. Therefore, the leaked airflow is mainly concentrated in the second air guide ring 12. Near the inner surface, the air flows in the opposite direction to the air outlet. The leaked air is reintegrated into the airflow in the air guide 1 through the check channel 3 between the inner ring 2 and the air guide 1. This can effectively solve the problem of leakage loss in the radial clearance at the blade tip of the axial flow fan under high static pressure conditions. Since the problem of leakage loss in the radial clearance at the blade tip of the axial flow fan can be effectively solved through the check channel 3, there is no need to worry about leakage loss in the radial clearance at the blade tip. Therefore, the radial clearance at the blade tip of the axial flow fan can be widened to ensure that the axial flow fan has a sufficiently wide radial clearance at the blade tip and improve safety.

[0045] This application addresses the problem of leakage loss in the radial clearance at the blade tip of an axial flow fan under high static pressure conditions, thereby effectively increasing the air volume and improving the efficiency of the axial flow fan.

[0046] Specifically, the embedded ring 2 is coaxially arranged with the air guide duct 1, and the width of the check channel 3 formed between the air guide duct 1 and the embedded ring 2 is uniform, so that any leakage generated at the radial clearance at the tip of the axial flow fan blade 5 can be effectively returned to the airflow in the air guide duct 1 through the check channel 3. Of course, the embedded ring 2 can also be eccentrically arranged with the air guide duct 1, and the width of the check channel 3 will be uneven, but it can still prevent leakage losses at the radial clearance at the tip of the blade.

[0047] In related technologies, the problem of tip leakage loss is reduced by decreasing the radial clearance at the tip of the axial flow fan (i.e., the gap between the axial flow fan blade 5 and the air guide duct 1). However, due to the reduction in the radial clearance at the tip, when the axial flow fan is in an unstable operating state, such as when foreign objects are embedded, the axial flow fan blade 5 is prone to breakage, or the axial flow fan blade 5 and the air guide duct 1 may freeze at low temperatures, resulting in the inability to operate normally. In this application, by setting the air guide ring to form a check flow channel 3 by embedding an inner ring 2 in the outer air guide duct 1, the problem of tip leakage loss can be effectively solved without reducing the radial clearance at the tip, effectively increasing the fan's air volume and efficiency under high static pressure conditions; at the same time, ensuring a wider radial clearance at the tip can effectively prevent damage to the axial flow fan blade 5 when foreign objects are embedded and prevent the axial flow fan blade 5 and the air guide duct 1 from freezing in low-temperature environments, thus improving safety.

[0048] Optionally, the first air guide ring 11, the second air guide ring 12, and the connecting part 13 can also be separately provided from the air guide tube 1. The first air guide ring 11, the second air guide ring 12, and the connecting part 13 are independent structures provided in the air guide tube 1. The first air guide ring 11, the connecting part 13, and the second air guide ring 12 form a check flow channel 3 with the embedded ring body 2.

[0049] In some embodiments, the connecting portion 13 is provided with a groove 131 on the side facing the inner ring 2, and the end of the inner ring 2 facing the groove 131 has an arc surface 21. The arc surface 21 and the groove 131 are arranged with the same center. A check section 31 of the check flow channel 3 is formed between the arc surface 21 and the groove 131. The check section 31 is used to change the flow direction of the leaked airflow.

[0050] In this application, by setting the arc surface 21 and the groove 131 at the same center, a semi-annular check section 31 is formed between the connecting part 13 and the arc surface 21, so that the air leaking in the check channel 3 can change its flow direction and be incorporated into the air in the air guide duct 1, thereby avoiding leakage loss.

[0051] Specifically, the leaked air changes its flow direction after passing through the check section 31 and is then discharged and re-integrated into the airflow in the air duct 1. The flow direction of the leaked air during discharge is set at an angle to the flow direction of the air inside the air duct 1, ensuring that the air after changing its flow direction through the check section 31 can be effectively integrated into the airflow inside the air duct 1. The arc surface 21 and the groove 131 are set with the same center, which can ensure that the width of the check section 31 of the check channel 3 is uniform, ensuring the uniformity of airflow distribution during the check process.

[0052] Optionally, the arc surface 21 and the groove 131 can also be set to be non-concentric, so that the width of the check section 31 gradually widens or widens first and then narrows, which can also achieve the check effect and reduce leakage loss in the radial clearance of the blade tip.

[0053] In some embodiments, the embedded ring 2 further includes a first surface 22 facing the check channel 3, the first surface 22 being connected to one end of the arc surface 21, and a leakage section 32 of the check channel 3 being formed between the first surface 22 and the second air guide ring 12, the leakage section 32 being used to guide the leaked airflow to the check section 31.

[0054] In this application, the air leaking from the radial gap at the blade tip enters the leakage section 32 of the check channel 3, and then enters the check channel 31 from the output end of the leakage section 32. The leakage section 32 is an annular sandwich layer coaxially arranged with the air guide duct 1. The leakage generated at the radial gap at the blade tip occurs between the end of the second air guide ring 12 and the axial flow blade 5. The direction of the leaking airflow is opposite to that of the airflow in the air duct. One end of the leakage section 32 is connected to the leaking airflow, and the other end is connected to the check channel 31. By setting a leakage section 32 at the input end of the check channel 31, the leaking airflow can smoothly enter the leakage section 32, and then enter the check channel 31 through the leakage section 32. The leakage section 32 plays a guiding and collecting role for the leaking airflow. The leaking airflow can easily flow back to the check channel 31 through the leakage section 32, and then change its flow direction through the check channel 31 and merge into the airflow in the air guide duct 1.

[0055] like Figure 7 As shown, specifically, the width of the leakage section 32 of the check channel 3 is equal to the width of the check section 31, so that the gas in the check channel 3 can return evenly to the airflow in the guide tube 1 without causing airflow turbulence, thus ensuring the check effect. In this embodiment, the distance of the radial clearance at the blade tip is c, a is the diameter at the minimum inner diameter of the first guide ring 11, b is the diameter of the axial flow fan blade 5, and c = 0.5 * (ab).

[0056] In some embodiments, the distance between the first guide ring 11 and the tip of the axial flow fan 5 is the tip radial clearance c, and the width of the check flow channel is h. c and h satisfy the following relationship: h = 0.5 * c ~ c.

[0057] In this application, the width h of the check channel 3 is set to 0.5 to 1 times the radial clearance c at the blade tip, so that the leaked airflow can maintain a certain wind speed in the check channel 3, so that the leaked airflow can be smoothly incorporated into the main airflow of the guide tube 1 when it is discharged at the output end of the check channel 3.

[0058] In one possible implementation, the distance between the first guide ring 11 and the tip of the axial flow fan blade 5 is the radial clearance c at the tip of the blade, and the radius of the arc surface is f. c and f satisfy the following relationship: f = 0.8 * c ~ 1.2 * c.

[0059] In this application, g is the radius of the arc of the groove 131 of the connecting part 13, and its value is: g = f + h. By setting f to 0.8*c ~ 1.2*c, the width of the check channel 3 is ensured, and the check section 31 of the check channel 3 can be formed into a semi-circle, thereby ensuring that the leaked airflow can return and merge into the main airflow.

[0060] In one possible implementation, the axial length of the second air guide ring is d, and the length of the second surface of the embedded ring along the axial direction of the air guide tube is e. d and e satisfy the following relationship: e = 0.5*d ~ 0.8*d.

[0061] Specifically, d represents the axial length of the second guide ring 12, with a value ranging from d = 0.3*k to 0.5*k, where k is the axial height of the axial fan blade 5. The axial height of the axial fan blade 5 is greater than the axial length of the second guide ring 12, ensuring that the suction surface and pressure surface of the axial fan blade 5 are located within the first guide ring 11 and the second guide ring 12, respectively, so that leakage occurs at the gap between the axial fan blade 5 and the second guide ring 12. To ensure leakage occurs on the inner surface of the second guide ring 12, the length of d must be greater than the length of e, meaning the second guide ring 12 has a portion extending to the outside of the check channel 3. e is set to 0.5*d to 0.8*d, allowing the leaking airflow to fully enter the leakage section 32 of the check channel 3, preventing the leaking airflow from flowing along the second surface of the embedded ring 2 due to the shorter length e of the second surface.

[0062] The inner diameter l of the second guide ring 12 is greater than a; this causes the main airflow in the guide tube 1 to diverge when it flows from the first guide ring 11 to the second guide ring 12, thus causing the leakage to mainly occur on the inner surface of the second guide ring 12. The leaking airflow is redirected and rejoined the main airflow through the check flow channel 3, and the gap between the axial flow fan blade 5 and the first guide ring 11 is sealed by air pressure, so that leakage will not occur at the radial gap at the blade tip between the axial flow fan blade 5 and the first guide ring 11.

[0063] In some embodiments, the embedded ring 2 further includes a second surface 23 away from the check channel 3, one end of the second surface 23 being connected to the end of the arc surface 21 away from the first surface 22.

[0064] like Figure 3 As shown in this application, the embedded ring 2 is formed by connecting the first surface 22, the arc surface 21, and the second surface 23 end to end. This ensures that the leakage section 32 has sufficient width for airflow leakage, and that the arc surface 21 has a wide radius to cooperate with the groove 131, thereby effectively turning the airflow entering the check section 31. The second surface 23 can guide the airflow from the first guide ring 11 to the second guide ring 12. The airflow led out from the check channel 3 is incorporated into the main airflow of the air duct 1 at the output end of the first guide ring 11. This can seal the radial gap at the blade tip between the axial flow fan blade 5 and the first guide ring 11, preventing leakage at the inner surface of the first guide ring 11. At the same time, the connection between the second surface 23 and the first surface 22 can minimize the occupancy of the embedded ring 2 on the internal air outlet space of the air duct 1.

[0065] Optionally, a third surface can be provided between the first surface 22 and the second surface 23. The third surface can be a curved surface, a plane, or an inclined surface.

[0066] Specifically, the first surface 22 is a plane, and the second surface 23 is either a plane or a concave structure.

[0067] In some embodiments, the end of the second surface 23 away from the arc surface 21 is connected to the end of the first surface 22 away from the arc surface 21. The first surface 22 is parallel to the axial direction of the air guide tube 1. An angle γ is formed between the second surface 23 and the first surface 22, and the following condition is satisfied: 10°≤γ≤20°.

[0068] In this application, an angle γ is formed between the first surface 22 and the second surface 23, 10°≤γ≤20°, so that the first surface 22 and the second surface 23 have a gradual thickness. This allows the airflow at the first guide ring 11 to flow smoothly to the second guide ring 12, completing the transition of the airflow between the first guide ring 11 and the second guide ring 12. This ensures that the airflow diffuses evenly when it transitions from the first guide ring 11 to the second guide ring 12, reducing local pressure loss. The air pressure of the airflow after uniform diffusion is reduced, which can also reduce the pressure difference between the airflow and the air inlet surface of the axial flow fan blade 5. By reducing the pressure difference on both sides of the axial flow fan blade 5, the leakage of the radial clearance at the blade tip is reduced. The airflow led out by the check channel 3 is combined with the airflow into the guide tube 1.

[0069] In this embodiment, the axial height of the first guide ring 11 is designed according to different axial flow fans, and no specific requirements are made for it; the axial height of the second guide ring 12 is also designed according to different axial flow fans, and no specific requirements are made for it. As long as the first guide ring 11 corresponds to the suction surface of the axial flow fan blade 5, and the second guide ring 12 corresponds to the pressure surface of the axial flow fan blade 5, the airflow leaking through the radial gap at the blade tip can enter the check channel 3.

[0070] In some embodiments, the connecting part 13 is provided with a positioning slot 132, and the inner ring 2 is provided with a first positioning block 24 at one end facing the connecting part 13, and the first positioning block 24 is inserted into the positioning slot 132.

[0071] In this application, the connecting part 13 is provided with a plurality of positioning slots 132 along the circumferential direction, and the inner ring 2 is provided with a plurality of first positioning blocks 24 at one end facing the connecting part 13. The plurality of first positioning blocks 24 are respectively inserted into the plurality of positioning slots 132, thereby positioning the inner ring 2 along the axial direction and ensuring the fixing effect between the inner ring 2 and the air guide 1.

[0072] In some embodiments, the outer surface of the inner ring 2 is provided with a plurality of second positioning blocks 25 along the circumferential direction. The plurality of second positioning blocks 25 respectively abut against the inner surface of the second air guide ring 12. The air guide ring also includes a fastener 4 disposed on the air guide tube 1, and the fastener 4 is connected to the second positioning blocks 25.

[0073] like Figure 6 As shown in this application, the second positioning block 25 on the outer circumference of the embedded ring 2 abuts against the inner surface of the second air guide ring 12, thereby positioning the embedded ring 2 radially and further improving the fixing effect of the embedded ring 2. The fastener 4 is a screw, which connects the air guide tube 1 and the second positioning block 25 of the embedded ring 2, thereby completing the fixed connection between the air guide tube 1 and the embedded ring 2. Specifically, the inner ring of the second air guide ring 12 is provided with a positioning groove 121 radially. The positioning groove 121 extends along the axial direction of the air guide tube 1. One end of the positioning groove 121 is an inlet, and the other end has a supporting step 122. The second positioning block 25 is inserted into the positioning groove 121 through the inlet and supported by the supporting step 122, which can further position the embedded ring 2 in the circumferential direction.

[0074] The second positioning block 25 has a threaded hole on its outer side and a through hole 123 in its positioning groove. The through hole 123 is arranged radially along the air guide tube. The fastener 4 passes through the through hole 123 and is threadedly connected to the threaded hole of the second positioning block 25, thus completing the axial and radial fixation of the inner ring body and the air guide tube.

[0075] Specifically, depending on the diameter of the air guide ring, the number of second positioning blocks can be set to 4 to 12 to ensure the radial positioning effect between the embedded ring and the air guide ring.

[0076] Optionally, the connection between the embedded ring 2 and the air guide 1 is not limited to the above connection method. The embedded ring 2 can also be integrally formed with the air guide 1, as long as a check flow channel 3 is formed between the embedded ring 2 and the second air guide ring 12 and the connecting part 13 of the air guide 1.

[0077] In some embodiments, the air duct 1 further includes an air inlet ring 14 disposed at the input end of the first air guide ring 11, and the first air guide ring 11 is gradually expanded along the direction from the second air guide ring 12 to the air inlet ring 14.

[0078] The air inlet ring 14 in this application adopts a gradually expanding arc structure. The structure of the air inlet ring 14 is not limited to an arc, but can also use straight line segments, spline curves, etc. The first air guide ring 11 is gradually expanded along the direction from the second air guide ring 12 to the air inlet ring 14. The angle between the profile of the first air guide ring 11 and the axial direction of the axial flow fan is β, and its value range is: 5°≤β≤12°. The gradually expanding design of the first air guide ring 11 increases the air inlet area and creates more favorable air inlet conditions for the axial flow fan.

[0079] In some embodiments, the air duct 1 further includes an air outlet ring 15 disposed at the output end of the second air guide ring 12, and the air outlet ring 15 is gradually expanded along the air outlet direction.

[0080] In this application, the angle between the profile of the air outlet ring 15 and the axial direction of the axial flow fan is α, and its value range is: 0°<α≤15°. The second air guide ring 12 combined with the air outlet ring 15 makes the outlet area of ​​the air guide ring gradually expand, which can reduce the wind speed and thus reduce the air outlet noise.

[0081] The air guide ring drives the air in the air guide tube 1 to flow axially through the axial flow fan blade 5. A radial gap is formed between the axial flow fan blade 5 and the air guide tube 1. There is a pressure difference between the pressure surface and the suction surface of the axial flow fan blade 5, which causes some airflow to leak through the radial gap. The leaked air is reintegrated into the airflow in the air guide tube 1 through the check flow channel 3 between the inner ring body 2 and the air guide tube 1. This can effectively solve the problem of leakage loss in the radial gap at the blade tip of the axial flow fan under high static pressure conditions. At the same time, it can ensure that the axial flow fan has a sufficiently wide radial gap at the blade tip, thus improving safety.

[0082] Figure 9 This diagram shows a three-dimensional structural schematic of an axial flow fan provided in an embodiment of this application.

[0083] like Figure 9As shown, this application embodiment provides an axial flow fan, including: the above-mentioned air guide ring; and axial flow fan blades 5, which are disposed in the air guide tube 1 of the air guide ring, wherein the suction surface and the pressure surface of the axial flow fan blades 5 correspond to the first air guide ring 11 and the second air guide ring 12, respectively.

[0084] Specifically, the axial flow fan also includes a fan mounting panel 6 located at the air inlet end of the air guide ring. A motor bracket 7 is provided on the fan mounting panel 6, and a motor 8 is mounted on the motor bracket 7. The power output end of the motor 8 is connected to the axial flow fan blade 5, and the motor 8 drives the axial flow fan blade 5 to rotate to achieve air delivery. The axial flow fan also includes a mesh cover 9 located at the air outlet end of the air guide ring, which prevents some objects from entering the air guide ring and damaging the axial flow fan blade 5.

[0085] In this application, by adopting the axial flow fan with the structure of this application, the airflow under high static pressure conditions is increased by up to 7.5% compared with conventional blade design, because the check flow channel 3 in the guide ring prevents the leakage airflow. Under the same impeller size and the same speed, the airflow of the axial flow fan is increased by up to 7.5%. The calculation data is shown in Table 1.

[0086] Table 1 Comparison of measured air volume for different airfoil design methods

[0087]

[0088] This application provides an air conditioner that includes the axial flow fan described above.

[0089] In this application, by adopting the axial flow fan of this application, the air conditioner can effectively reduce leakage losses at the radial clearance of the blade tip, improve the air volume and efficiency of the axial flow fan, and improve the safety during operation due to the wider radial clearance of the blade tip.

[0090] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0091] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0092] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A wind guide ring applied to an axial flow fan; characterized in that, The air guide ring includes: An air guide duct (1) has a first air guide ring (11) and a second air guide ring (12) arranged sequentially on its inner surface along the air outlet direction. A connecting part (13) is provided between the first air guide ring (11) and the second air guide ring (12). The inner diameter of the first air guide ring (11) is smaller than the inner diameter of the second air guide ring (12). The first air guide ring (11) and the second air guide ring (12) correspond to the suction surface and pressure surface of the axial flow fan blade (5) inside the axial flow fan, respectively. An embedded ring (2) is located inside the second air guide ring (12) and adjacent to the first air guide ring (11). The inner diameter of the embedded ring (2) is larger than the inner diameter of the first air guide ring (11). The gap between the embedded ring (2), the second air guide ring (12) and the connecting part (13) forms a check flow channel (3). The distance between the first air guide ring and the tip of the axial flow fan blade is the tip radial clearance c, and the width of the check flow channel is h. c and h satisfy the following relationship: h = 0.5 * c ~ c.

2. The air guide ring according to claim 1, characterized in that, The connecting part (13) is provided with a groove (131) on the side facing the inner ring (2). The inner ring (2) has an arc surface (21) at one end facing the groove (131). The arc surface (21) and the groove (131) form a check section (31) of the check channel (3). The check section (31) is used to change the flow direction of the leaking air.

3. The wind ring of claim 2, wherein, The embedded ring (2) also includes a first surface (22) facing the check channel (3), the first surface (22) being connected to one end of the arc surface (21), and a leakage section (32) of the check channel (3) being formed between the first surface (22) and the second air guide ring (12), the leakage section (32) being used to guide the leaked airflow to the check section (31).

4. The wind ring of claim 3, wherein, The embedded ring (2) also includes a second surface (23) away from the check channel (3), one end of the second surface (23) being connected to the end of the arc surface (21) away from the first surface (22).

5. The wind ring of claim 4, wherein, The end of the second surface (23) away from the arc surface (21) is connected to the end of the first surface (22) away from the arc surface (21). The first surface (22) is parallel to the axial direction of the air guide tube (1). The second surface (23) and the first surface (22) form an angle γ, and satisfy the following condition: 10°≤γ≤20°.

6. The air ring of claim 1, wherein The connecting part (13) is provided with a positioning slot (132), and the inner ring (2) is provided with a first positioning block (24) at one end facing the connecting part (13), and the first positioning block (24) is inserted into the positioning slot (132).

7. The wind ring of claim 6, wherein, The outer surface of the embedded ring (2) is provided with a plurality of second positioning blocks (25) along the circumferential direction. The plurality of second positioning blocks (25) respectively abut against the inner surface of the second air guide ring (12). The air guide ring also includes fasteners (4) provided on the air guide tube (1). The fasteners (4) are connected to the second positioning blocks (25).

8. The wind ring of claim 1, wherein, The air guide duct (1) also includes an air inlet ring (14) disposed at the input end of the first air guide ring (11), and the first air guide ring (11) is gradually expanded along the direction from the second air guide ring (12) to the air inlet ring (14).

9. The wind ring of claim 1, wherein, The air guide tube (1) also includes an air outlet ring (15) disposed at the output end of the second air guide ring (12), and the air outlet ring (15) is gradually expanded along the air outlet direction.

10. The wind ring of claim 2, wherein, The distance between the first air guide ring and the tip of the axial flow fan blade is the radial clearance c at the tip of the blade, and the radius of the arc surface is f. c and f satisfy the following relationship: f = 0.8 * c ~ 1.2 * c.

11. The wind ring of claim 4, wherein, The axial length of the second air guide ring is d, and the length of the second surface of the embedded ring along the axial direction of the air guide tube is e. d and e satisfy the following relationship: e = 0.5*d ~ 0.8*d.

12. An axial flow fan characterised in that, include: The air guide ring as described in any one of claims 1-11; as well as An axial flow fan blade (5) is disposed inside the air guide tube (1) of the air guide ring. The suction surface and pressure surface of the axial flow fan blade (5) correspond to the first air guide ring (11) and the second air guide ring (12), respectively.

13. An air conditioner characterized by comprising: Including the axial flow fan as described in claim 12.

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