OA21844A - Combined fan blade structure and air outlet device. - Google Patents

Abstract

Disclosed are a combined fan blade structure and an air outlet device. The combined fan blade structure (100) comprises: an inner hub (110), an outer hub (120), a first blade set (130), and a second blade set (140). The outer hub (120) and the inner hub (110) are coaxially arranged, the first blade set (130) is connected to an outer peripheral surface of the outer hub (120), the second blade set (140) is located between the inner hub (110) and the outer hub (120), and the outer hub (120) blocks the second blade set (140). By means of the combined fan blade structure, the air outlet volume and efficiency of the fan can be improved.

Description

COMBINED FAN BLADE STRUCTURE AND AIR OUTLET DEVICE

CROSS REFERENCE TO A RELATED APPLICATION

The present disclosure is filed on the basis of Chinese Patent Application No. 202210405774.7 filed on April 18, 2022, and claims priority from the Chinese patent application, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a fan blade structure combined with an air outlet device.

CONTEXT

The statements herein merely provide background information related to the present disclosure and do not necessarily constitute prior art.

In fan technology, axial flow fans are typically used to meet the flow rate requirements of large air volumes. The air volume of axial flow fans is increased by reducing the hub ratio, which is the ratio of hub diameter to rotor diameter. However, the hub ratio of axial flow fans is limited. An excessively low hub ratio reduces fan efficiency, making it difficult for the fan to balance the requirements for high air volume and efficient air flow.

SUMMARY

The present disclosure aims to solve at least one of the technical problems existing in the prior art. To this end, the present disclosure provides a combined fan blade structure and an air outlet device. Accordingly, the air volume and air outlet efficiency of the fan blade structure can be improved.

According to one embodiment in a first aspect of the present disclosure, the combined fan blade structure comprises:

an inner hub;

-221844 an outer hub arranged coaxially with the inner hub and arranged around the inner hub;

a first set of blades connected to an outer peripheral surface of the outer hub, wherein the first set of blades comprises a plurality of primary blades, and this plurality of primary blades is distributed at intervals in a circumferential direction of the outer hub; and a second set of blades connected between the inner hub and the outer hub and comprising a plurality of secondary blades, wherein this plurality of secondary blades is distributed at intervals in a circumferential direction of the inner hub, and the outer hub blocks the sides of the secondary blades facing the outer hub.

According to one embodiment of the present disclosure, the combined fan blade structure has at least the following beneficial effects.

In the combined fan blade structure provided in one embodiment of the present disclosure, the first set of blades and the second set of blades are respectively located on the inner and outer sides of the outer hub in the radial direction and can both receive incoming air from the external environment, thereby making the combined fan blade structure have a large air inlet area. The first set of blades and the second set of blades can circulate air on the air inlet side of the fan blade structure to form an airflow and discharge the airflow, thereby increasing the air volume of the fan blade structure. The first set of blades can connect more primary blades, thereby increasing the air volume of the fan blade structure. The number of secondary blades is not affected by the size of the hubs and is not limited by the hub ratio, and the size of the inner hub is not limited. The airflows generated by the first set of blades and the second set of blades are combined and discharged. Compared with the traditional axial flow fan, the fan blade structure can generate a larger air volume at the same rotational speed and requires a lower rotational speed to generate the same air volume, thereby improving the air volume and air outlet efficiency of the fan blade structure.

According to some embodiments of the present disclosure, the primary blades comprise axial flow blades or oblique flow blades, and/or the secondary blades comprise centrifugal blades.

According to some embodiments of the present disclosure, the primary blades are axial flow blades and the projections of adjacent primary blades in a plane perpendicular to

-321844 an axial direction are spaced in the circumferential direction;

or, the primary blades are oblique flow blades, and the projections of adjacent primary blades in a plane perpendicular to an axial direction have overlapping areas in the circumferential direction.

According to some embodiments of the present disclosure, the outer hub is inclined in a direction opposite to an axis of rotation of the inner hub in an air outlet direction.

According to some embodiments of the present disclosure, the inner hub is inclined in the direction opposite to the axis of rotation of the inner hub in the direction of the air outlet.

According to some embodiments of the present disclosure, the inner hub has an opening facing one side of the air outlet.

According to some embodiments of the present disclosure, the inner hub comprises a first air guide portion and a second air guide portion connected to each other, the first air guide portion is located on an air inlet side of the inner hub, the second air guide portion is disposed facing the outer hub in a radial direction relative to the outer hub, and the secondary blades are connected to the second air guide portion.

According to some embodiments of the present disclosure, the first air guide portion and/or the second air guide portion are inclined in the direction opposite to the rotation axis of the inner hub in the direction of air outlet.

According to some embodiments of the present disclosure, an acute angle between the first air guide portion and the second air guide portion and the rotation axis of the inner hub gradually decreases in the air outlet direction.

According to some embodiments of the present disclosure, the first air guide portion is higher in the axial direction than the air inlet side of the outer hub.

According to some embodiments of the present disclosure, a distance between adjacent secondary blades in an inner circumferential direction of the outer hub is shorter than a distance between adjacent primary blades in an outer circumferential direction of the outer hub.

According to some embodiments of the present disclosure, a hub ratio of the inner hub to the secondary blades is smaller than a hub ratio of the outer hub to the primary blades.

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An air outlet device according to an embodiment of a second aspect of the present disclosure comprises:

the combined fan blade structure according to one embodiment in the first aspect;

an air deflector provided with an air inlet and an air outlet at both ends, wherein the air deflector has an air guide cavity therein, the air inlet and the air outlet are both connected to the air guide cavity, and the combined fan blade structure is housed in the air guide cavity and coaxially arranged with the air deflector; and a power element connected to one end of the inner hub near the air outlet and configured to drive the inner hub to rotate.

According to some embodiments of the present disclosure, the air outlet device further comprises a mounting seat and a plurality of guide vanes, the mounting seat and the plurality of guide vanes are all housed in the air deflector, the mounting seat and the air deflector are coaxially arranged, one end of the power element connected to the inner hub passes through the mounting seat, the plurality of guide vanes are arranged around an outer periphery of the mounting seat, and the guide vanes are connected between the air deflector and the mounting seat.

According to some embodiments of the present disclosure, an outer wall of the mounting seat is located radially inward of an inner wall of the outer hub at one end near the air outlet.

According to some embodiments of the present disclosure, the mounting seat comprises a first connecting piece, a second connecting piece and a transition piece, wherein the first connecting piece is perpendicular to the rotation axis of the inner hub, the second connecting piece is arranged around an outer periphery of the first connecting piece, the transition piece is connected between the first connecting piece and the second connecting piece, and the transition piece is inclined in the direction opposite to the rotation axis of the inner hub in the direction of the air outlet.

Additional aspects and advantages of this disclosure will be elaborated upon in the following description, and will be partially apparent from the description, or understood by practice of this disclosure.

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BRIEF DESCRIPTION OF THE DRAWINGS

To better clarify the embodiments of the present disclosure or the technical solution in the prior art, the drawings necessary to illustrate the embodiments or the prior art will be simply described below. It is obvious that the drawings described below simply illustrate some embodiments of the present disclosure. Persons having ordinary skill in the art can obtain other drawings according to these drawings without creative efforts based on these drawings.

FIG. 1 is a schematic structural diagram of a combined fan blade structure according to certain embodiments of the present disclosure.

FIG. 2 is a top view of the fan blade structure combined with FIG. 1.

FIG. 3 is a schematic structural diagram of the combined fan blade structure according to other embodiments of the present disclosure.

FIG. 4 is a top view of the fan blade structure combined with FIG. 3.

FIG. 5 is a cross-sectional view of the air outlet of the combined fan blade structure of FIG. 1.

FIG. 6 is a schematic structural diagram of certain embodiments of an inner hub of FIG. 5.

FIG. 7 is a cross-sectional view of an air outlet device according to certain embodiments of the present disclosure.

FIG. 8 is a schematic diagram of the airflow of the air outlet device in FIG. 7.

FIG. 9 is a three-dimensional view of the air outlet device in FIG. 7.

Reference figures:

Combined fan blade structure 100; inner hub 110; first air guide portion 111; second air guide portion 112; mounting piece 113; outer hub 120; first blade set 130; primary blade 131; second blade set 140; secondary blade 141; air deflector 200; air inlet 210; air outlet 220; air guide cavity 230; power element 300; mounting seat 400; first connecting piece 410; second connecting piece 420; transition piece 430; guide vane 500.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described in detail below, including

-621844 examples are shown in the drawings, the same or similar reference signs throughout the document indicate the same or similar components or components having the same or similar function. The embodiments described with reference to the drawings are exemplary, which are merely used to explain the present disclosure, instead of being understood as a limitation to the present disclosure.

In describing this disclosure, it is understood that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left" and "right", and the like are based on the orientation or positional relationships as shown in the drawings, to facilitate the description of this disclosure and only to simplify the description, rather than to indicate or imply that the apparatus or element mentioned necessarily has a particular orientation and must be constructed and operated in that particular orientation. Accordingly, these terms should not be understood as limitations on this disclosure.

In the description of the present disclosure, the meaning of "several" is one or more, the meaning of "a plurality" is two or more; "greater than", "less than", "exceeding" and other similar terms are understood to exclude the original number, and "above", "below", "within" and other similar terms are understood to include the original number. The words "primary/first" and "secondary/second" are merely used to distinguish the technical features, instead of being understood to indicate or imply relative importance or implicitly indicate the quantity of the technical features shown or implicitly indicate the priority relationship of the technical features shown.

In the description of this disclosure, unless explicitly stated otherwise, the terms “configure,” “install,” “connect,” and similar terms are to be understood in their general meaning. Persons of ordinary skill in the art can reasonably determine the specific meaning of the terms in this disclosure in combination with the specific content of the technical solution.

In the description of this disclosure, the description with reference to the terms "some embodiments", "schematic embodiment", "example", "specific example" or "some examples" and other similar terms means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least some embodiments or examples of this disclosure. In this specification, the schematic expression of the above terms does not necessarily refer to the same embodiment or example. In addition,

-721844 the specific features, structures, materials or functionalities described may be combined in one or more embodiments or examples as appropriate.

With reference to FIGURES 1-4, one embodiment of the present disclosure provides a combined fan blade structure 100 (which may also be referred to as a combined air outlet structure, hereinafter referred to as the fan blade structure 100). The combined fan blade structure 100 includes an inner hub 110, an outer hub 120, a first blade set 130, and a second blade set 140. The inner hub 110 and the outer hub 120 are coaxially arranged. The outer hub 120 is arranged around the inner hub 110 with a gap therebetween. The first set of blades 130 is located radially outside the second set of blades 140. The first set of blades 130 is connected to an outer peripheral surface of the outer hub 120, and the second set of blades 140 is located between the inner hub 110 and the outer hub 120. Since the first set of blades 130 and the second set of blades 140 are respectively located on the inner and outer sides of the outer hub 120 in the radial direction and can both receive incoming air from the external environment, the combined fan blade structure 100 has a large air inlet area. The first set of blades 130 and the second set of blades 140 can circulate air from the air inlet side of the fan blade structure 100 to form an airflow and discharge the airflow, thereby increasing the air volume of the fan blade structure 100.

More specifically, the first set of blades 130 comprises a plurality of primary blades 131 distributed at intervals in the circumferential direction of the outer hub 120. The second set of blades 140 comprises a plurality of secondary blades 141 distributed at intervals in the circumferential direction of the inner hub 110. Both sides of the secondary blades 141 are respectively connected to the outer hub 120 and the inner hub 110 in a radial direction of the inner hub 110. The inner hub 110 can be connected to a power element and drives simultaneous rotation of the primary blades 131 and the second set of blades 140 to form an airflow. More specifically, the outer hub 120 blocks the sides of the secondary blades 141 facing the outer hub 120 to guide the airflow. Optionally, one end of each of the secondary blades 141 near the outer hub 120 may be partially connected to the outer hub 120, or be completely connected to the outer hub 120. Optionally, the plurality of primary blades 131 and the plurality of secondary blades 141 are inclined in the same predefined direction from their respective bases connected to the outer hub 120. Optionally, the predefined direction may be clockwise or counterclockwise.

s 21844

In addition, in some embodiments of the present disclosure, the primary blades 131 are configured as axial flow blades or oblique flow blades, and the secondary blades 141 are configured as centrifugal blades. The number of centrifugal blades is not affected by the size of the hubs and is not limited by the hub ratio. To meet the design requirements of small hubs and multiple blades, the size of the inner hub 110 is not limited, and a small inner hub 110 can be designed. Compared with the simple configuration of axial flow blades, configuring the secondary blades 141 as centrifugal fan blades can increase the number of secondary blades 141, which is conducive to increasing the air volume. In addition, the outer hub 120 blocking the sides of the secondary blades 141 facing the outer hub 120 can guide the airflow generated by the secondary blades 141 in the axial direction of the fan blade structure 100, so that the second set of blades 140 discharges air axially. The first set of blades 130 can generate an axial or oblique airflow. Since the first set of blades 130 is connected to the outer hub 120 which has a larger size and thus can connect a larger number of primary blades 131, the air volume of the fan blade structure 100 can be increased. The airflows generated by the first set of blades 130 and the second set of blades 140 are discharged after combination. Compared with the traditional axial flow fan, the fan blade structure 100 provided in the embodiment of the present disclosure can generate a larger air volume at the same rotational speed and requires a lower rotational speed to generate the same air volume, thereby improving the air volume and air outlet efficiency of the fan blade structure 100.

It should be noted that the airflow generated by the centrifugal blades has a greater pressure. Once the airflow generated by the second set of blades 140 is mixed with the airflow generated by the first set of blades 130, the pressure of the mixed airflow can be increased. Therefore, the fan blade structure 100 is suitable for air outlet environments with high pressure and large air volume. In one embodiment of the present disclosure, as shown in FIG. 5, the outer hub 120 guides the radial airflow generated by the second set of blades 140 axially, allowing the blade structure 100 to discharge the airflow axially. This makes it applicable to axial flow fans and increases the pressure of the combined airflow of the fan blade structure 100, which is beneficial for an increase in the airflow speed of the fan blade structure 100.

Additionally, the linear velocity on the inner sides of axial flow blades is generally lower than that on the outer sides, allowing the airflow generated by the axial flow blades

-921844 to have a slower indoor airflow and a faster outdoor airflow. In one embodiment of the present disclosure, by combining the first set of blades 130 and the second set of blades 140, and without a limit on the number of secondary blades 141, a large air volume can be generated. The airflow generated by the second set of blades 140 can compensate for the insufficient linear speed of the indoor side of the first set of blades 130, thereby making the airflow across the entire surface of the air outlet of the fan blade structure 100 more uniform.

With respect to FIGURES 1 and 2, in some embodiments, the primary blades 131 are axial flow blades. The first set of blades 130 discharges air in the axial direction, the mixed airflow of the first set of blades 130 and the second set of blades 140 is discharged in the axial direction, and the fan blade structure 100 discharges the airflow in the axial direction, and is suitable for environments with axial air discharge requirements. With respect to FIGURES 3 and 4, in other embodiments, the primary blades 131 are oblique flow blades. The first set of blades 130 discharges air obliquely, the mixed airflow of the first set of blades 130 and the second set of blades 140 is discharged in the axial direction and the oblique direction, and the fan blade structure 100 is suitable for environments with axial and oblique air discharge requirements.

As shown in FIG. 2, when the primary blades 131 are axial flow blades, the projections of adjacent primary blades 131 in the plane perpendicular to the axial direction do not overlap. In other words, the projections of adjacent primary blades 131 in the plane perpendicular to the axial direction are circumferentially spaced. The fan blade structure 100 can be molded in the axial direction and integrally formed by means of injection molding, etc. The processing cost of the fan blade structure 100 is low and the components do not need to be assembled, making it very convenient to use. As shown in FIG. 4, when the primary blades 131 are oblique flow blades, the projections of adjacent primary blades 131 in the plane perpendicular to the axial direction have overlapping areas in the circumferential direction. This prevents axial molding of the fan blade structure 100, but movable base molding (where a sliding mechanism is used to form structures that cannot be directly separated) can be applied, and the structure can still be integrally formed using injection molding. Compared with configuring the primary blades 131 as axial flow blades, the processing cost of oblique flow blades is higher, but at the same rotational speed, the generated airflow has a higher air volume and pressure. In addition, whether the primary blades 131 are axial flow blades or oblique flow blades, the combination of the first set of blades

-1021844

130 and the second set of blades 140 enables the fan blade structure 100 to produce a high volume, high pressure airflow and ensures efficient air exhaust.

As shown in FIG. 5, in the air outlet direction, the outer hub 120 is inclined in a direction opposite to the rotation axis of the inner hub 110, so that the outer hub 120 is inclined toward the outer side of the fan blade structure 100 relative to the central axis of the fan blade structure 100. In other words, the outer hub 120 has a gradually expanding structure in the air outlet direction. On the one hand, the secondary blades 141 are centrifugal blades, the airflow generated by the second set of blades 140 flows in the radial direction of the fan blade structure 100, the inclined arrangement of the outer hub 120 can reduce the impact of the second set of blades 140 on the outer hub 120, and the outer hub 120 can guide the airflow generated by the second set of blades 140 obliquely, so that the airflow can be more easily discharged between the inner hub 110 and the outer hub 120, avoiding the generation of turbulence or noise between the outer hub 120 and the inner hub 110. On the other hand, the airflow generated by the second set of blades 140 is discharged obliquely to the outside, the airflow generated by the first set of blades 130 flows obliquely to the outside, and the airflow generated by the second set of blades 140 flows obliquely to the outside. axial, and the airflows generated by the two can be rapidly mixed, so that, driven by the airflow generated by the second set of blades 140, the flow rate of the mixed airflow can be increased.

In some embodiments, as shown in FIGURES 5 to 8, in the air outlet direction, the inner hub 110 is inclined in the direction opposite to the rotation axis of the inner hub 110. In other words, the inner hub 110 has a gradually expanding structure in the air outlet direction. More specifically, the inner hub 110 has only one opening facing the air outlet side. The inclined arrangement of the inner hub 110 is also conducive to the introduction of airflow, and can increase the uniformity of air supply and discharge of the fan blade structure 100 and avoid turbulence or noise generated between the inner hub 110 and the outer hub 120.

As shown in FIG. 6, the inner hub 110 has a first air guide portion 111 and a second air guide portion 112. The first air guide portion 111 and the second air guide portion 112 are integrally connected. The first air guide portion 111 is located on the air inlet side of the inner hub 110. The second air guide portion 112 is arranged opposite the outer hub 120 in the radial direction of the outer hub 120. Both sides of the secondary blades 141 are respectively connected to the inner side of the outer hub 120 and the outer side of the second air guide portion 112. The first air guide portion 111 and the second air guide portion 112 can guide external air.

-1121844 to allow external air to enter between the inner hub 110 and the outer hub 120. In addition, the first air guide portion 111 can be connected to a power element, and the power element can supply power to the fan blade structure 100, so that the fan blade structure 100 generates an airflow.

More specifically, in some embodiments, the first air guide portion 111 is inclined in a direction opposite to the rotation axis of the inner hub 110, that is, the first air guide portion 111 is inclined from the air inlet side to the air outlet side of the fan blade structure 100, and the size of the first air guide portion 111 in the radial direction of the outer hub 120 gradually increases. The first air guide portion 111 guides the air in the external environment and quickly guides the air entering the fan blade structure 100 to the outer circumference of the inner hub 110 and reaches the area between the inner hub 110 and the outer hub 120, so that the air forms an airflow under the rotation of the second set of blades 140, thereby improving the efficiency of the air outlet of the fan blade structure 100.

The cross-section of the first air guide portion 111 in the axial direction of the fan blade structure 100 may be triangular or arc-shaped, i.e., the first air guide portion 111 may be a cone surface, a spherical surface, etc., to quickly achieve air guidance. In some embodiments, the cross-section of the first air guide portion 111 is arc-shaped, and the first air guide portion 111 and the second air guide portion 112 form a smooth transition at the connection point, so that air can flow along the outer surface of the inner hub 110 to avoid turbulence generated during air flow, thereby reducing noise emitted by the fan blade structure 100.

In addition, in the air outlet direction of the fan blade structure 100, the second air guide portion 112 is inclined in a direction opposite to the rotation axis of the inner hub 110, and the external air flows rapidly toward the second air guide portion 112, guided by the first air guide portion 111. The second air guide portion 112 directs the airflow generated by the second set of blades 140 obliquely outward. Directed by the second air guide portion 112, the airflow generated by the second set of blades 140 can be quickly mixed with the airflow generated by the first set of blades 130. In addition, since the outer hub 120 and the second air guide portion 112 are both inclined toward the outer side of the fan blade structure 100, the oblique guiding effect on the airflow generated by the second set of blades 140 can be improved, facilitating the rapid mixing of the airflows of the first set of blades 130 and the second set of blades.

-1221844

MO.

In some embodiments, in the air outlet direction, the acute angle between the first air guide portion 111 and the second air guide portion 112 and the rotation axis of the inner hub 110 gradually decreases, i.e., the first air guide portion 111 and the second air guide portion 112 are uniformly connected to form an arc and both protrude in a direction opposite to the rotation axis, which is beneficial for guiding the airflow along the outer surface of the inner hub 110, and promotes mixing of the airflow generated by the second set of blades 140 with the airflow generated by the first set of blades 130.

In some embodiments, the first air guide portion 111 is higher in the axial direction than the air inlet side of the outer hub 120, which can optimize the airflow guide angle in the middle portion of the second blade set 140, for example, increasing the airflow guide angle on the air inlet side in the middle portion of the centrifugal fan blades. The first air guide portion 111 of this embodiment is higher in the axial direction than the air inlet side of the outer hub 120, which can enhance the air guiding effect and increase the uniformity of air supply and discharge in the air duct between the inner hub 110 and the outer hub 120.

In some embodiments, the distance between adjacent secondary blades 141 in the inner circumferential direction of the outer hub 120 is shorter than that between adjacent primary blades 131 in the outer circumferential direction of the outer hub 120, i.e., the secondary blades 141 are arranged more densely than the primary blades 131. Since the secondary blades 141 are centrifugal blades, the number of the secondary blades 141 and the size of the inner hub 110 are not limited by the hub ratio. By providing a larger number of secondary blades 141, the air volume of the second set of blades 140 can be increased, thereby increasing the overall air volume of the fan blade structure 100. In addition, the hub ratio of the inner hub 110 to the secondary blades 141 is smaller than the hub ratio of the outer hub 120 to the primary blades 131. Therefore, the second set of blades 140 can generate an airflow with a larger air volume and higher pressure than the first set of blades 130, so that, compared with a traditional axial flow fan, the air volume and pressure of the fan blade structure 100 are effectively increased.

With reference to FIGURES 7 and 8, an embodiment of the present disclosure further provides an air outlet device, including the above combined air outlet structure 100, as well as an air deflector 200 and a power element 300. The air deflector 200 is provided with an air inlet 210 and an air outlet 220 at both ends. The air deflector 200 has an air guide cavity 230 therein. The air inlet 210 and the air outlet 220 are both connected to the air guide cavity 230. The combined fan blade structure 100 is housed in the air guide cavity 230 and arranged coaxially with the air deflector 200. External air enters the air guide cavity 230 from the air inlet 210. The power element 300 is connected to the end of the inner hub 110 near the air outlet 200 and is configured to drive the inner hub 110 to rotate. The first blade set 130 and the second blade set 140 form an airflow during rotation. The air passes through the fan blade structure 100 to form an airflow and is discharged from the air outlet 220.

As shown in FIG. 8, the air deflector 200 is coaxially arranged with the inner hub 110 and the outer hub 120. The power element 300 is connected to the air outlet side of the fan blade structure 100 and is located in the center of the fan blade structure 100. Due to the direction of the air deflector 200 and the power element 300, the airflow discharged from the air outlet 220 by the air outlet device is distributed in an annular area and is discharged in the axial direction of the air deflector 200. Constrained by the air deflector 200 and the power element 300, the airflow of the air outlet device has good linearity, which is suitable for environments with an axial air outlet and a fixed air supply.

As shown in FIGURES 7 and 9, the air outlet device further comprises a mounting seat 400 and a plurality of guide vanes 500. The mounting seat 400 and the plurality of guide vanes 500 are all housed in the air deflector 200. The mounting seat 400 and the air deflector 200 are coaxially arranged. One end of the mounting seat 400 is connected to the inner hub 110, and one end of the power element 300 connected to the inner hub 110 passes through the mounting seat 400. The mounting seat 400 is configured to support and install the power element 300. The plurality of guide vanes 500 are arranged around the outer periphery of the mounting seat 400. The two radial sides of the guide vanes 500 are respectively connected to the air deflector 200 and the mounting seat 400. The guide vanes 500 are used to connect the air deflector 200 to the mounting seat 400 and guide the airflow, so as to improve the coaxiality of the mounting seat 400 with the air deflector 200 and the overall structural strength of the mounting seat 400 and the air deflector 200, and to discharge the air flow in the air guide cavity 230 in the axial direction of the air deflector 200.

In addition, the plurality of guide vanes 500 are uniformly distributed in the circumferential direction of the mounting seat 400. By guiding the air flow in the air guide cavity

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230 by the guide vanes 500, uniformity of the air flow at the air outlet 220 can be improved. Optionally, the air deflector 200 is flared at one end of the air inlet 210 to facilitate the entry of external air into the air guide cavity 230.

More specifically, the mounting seat 400 comprises a first connecting piece 410 and a second connecting piece 420. The first connecting piece 410 is perpendicular to the rotation axis of the inner hub 110, and the second connecting piece 420 is annular and connected to the outer periphery of the first connecting piece 410. The first connecting piece 410 abuts against the power element 300, and the second connecting piece 420 is connected to the guide vanes 500. More specifically, as shown in FIGS. 6 and 7, the inner hub 110 comprises a mounting piece 113 connected to the inner side of the first air guide portion 111. The first connecting piece 410 is pierced with a hole to pass through the outlet end of the power element 300. The outlet end of the power element 300 is inserted into the mounting piece 113 to achieve the transmission of power from the power element 300 to the inner hub 110.

In addition, in the radial direction of the outer hub 120, the outer wall of the mounting seat 400 is located on the inner side of the inner wall of the outer hub 120 at one end near the air outlet 220, in order to prevent the mounting seat 400 from blocking the air discharge of the second blade assembly 140. The mounting seat 400 further comprises a transition piece 430. The two ends of the transition piece 430 are respectively connected to the first connection piece 410 and the second connection piece 420. In the direction of the air outlet, the transition piece 430 is inclined in a direction opposite to the rotation axis of the inner hub 110. The transition piece 430 can guide the air flow discharged from the fan blade structure 100 and guide the air flow between the second connection piece 420 and the air deflector. 200, so that the air flow is discharged in the axial direction of the air deflector 200.

Embodiments of the present disclosure are described in detail above in combination with the drawings, but the present disclosure is not limited to the above embodiments. In order not to deviate from the purpose of the present disclosure, several changes may also be made known to those of ordinary skill in the art. In addition, the embodiments of the present disclosure and the features in the embodiments may be combined with each other without conflict.

Claims (10)

1. A combined fan blade structure, comprising: an inner hub (110); an outer hub (120) disposed coaxially with the inner hub (110) and disposed around the inner hub (110); a first blade set (130) connected to an outer peripheral surface of the outer hub (120), wherein the first blade set (130) comprises a plurality of primary blades (131), and the plurality of primary blades (131) are distributed at intervals in a circumferential direction of the outer hub (120); and a second blade set (140) connected between the inner hub (110) and the outer hub (120), wherein the second blade set (140) comprises a plurality of secondary blades (141), the plurality of secondary blades (141) are distributed at intervals in a circumferential direction of the inner hub (110), and the outer hub (120) blocks the sides of the secondary blades (141) facing the outer hub (120). 2. The combined fan blade structure according to claim 1, wherein the primary blades (131) are axial flow blades, and the projections of adjacent primary blades (131) in a plane perpendicular to the axial direction are spaced apart in the circumferential direction; or, the primary blades (131) are oblique flow blades, and the projections of adjacent primary blades (131) in a plane perpendicular to an axial direction have overlapping areas in the circumferential direction. 3. The combined fan blade structure according to claim 1, wherein the outer hub (120) is inclined in a direction opposite to a rotation axis of the inner hub (110) in an air outlet direction, the inner hub (110) is inclined in the direction opposite to the rotation axis of the inner hub (110) in the air outlet direction, and wherein the inner hub (110) has an opening facing one side of the air outlet. 4. The combined fan blade structure according to claim 1, wherein the inner hub (110) comprises a first air guide portion (111) and a second air guide portion (112) connected to each other, the first air guide portion (111) is located on an air inlet side of the inner hub (110), the second air guide portion (112) is arranged opposite the outer hub (120) in a radial direction of the outer hub (120), and the secondary blades (141) are connected to the second air guide portion (112). -1621844 5. The combined fan blade structure according to claim 4, wherein the first air guide portion (111) and/or the second air guide portion (112) are inclined in the direction opposite to the rotation axis of the inner hub (110) in the air outlet direction, wherein an acute angle between the first air guide portion (111) and the second air guide portion (112) and the rotation axis of the inner hub (110) gradually decreases in the air outlet direction, and wherein the first air guide portion (111) is higher in the axial direction than the air inlet side of the outer hub (120). 6. The combined fan blade structure according to claim 1, wherein a distance between adjacent secondary blades (141) in an inner circumferential direction of the outer hub (120) is shorter than a distance between adjacent primary blades (131) in an outer circumferential direction of the outer hub (120). 7. The combined fan blade structure according to one of claims 1 to 6, wherein a hub ratio of the inner hub (110) to the secondary blades (141) is smaller than a hub ratio of the outer hub (120) to the primary blades (131). 8. An air outlet device, comprising: the combined fan blade structure (100) according to one of claims 1 to 7; an air deflector (200) provided with an air inlet (210) and an air outlet (220) at both ends, wherein the air deflector (200) has an air guide cavity (230) therein, the air inlet (210) and the air outlet (220) are both connected to the air guide cavity (230), and the combined fan blade structure (100) is housed in the air guide cavity (230) and coaxially arranged with the air deflector (200); and a power element (300) connected to one end of the inner hub (110) near the air outlet (220) and configured to drive the inner hub (110) to rotate. 9. The air outlet device according to claim 8, further comprising a mounting seat (400) and a plurality of guide vanes (500), wherein the mounting seat (400) and the plurality of guide vanes (500) are all housed in the air deflector (200), the mounting seat (400) and the air deflector (200) are coaxially arranged, one end of the power element (300) connected to the inner hub (110) passes through the mounting seat (400), the plurality of guide vanes (500) are arranged around an outer periphery of the mounting seat (400), and the guide vanes (500) are connected between the air deflector (200) and the mounting seat (400), and wherein an outer wall of the mounting seat (400) is -1721844 located radially inward of an inner wall of the outer hub (120) at one end near the air outlet (220). 10. The air outlet device according to claims 8 or 9, wherein the mounting seat (400) comprises a first connecting piece (410), a second connecting piece (420) and a transition piece (430), the first connecting piece (410) is perpendicular to the rotation axis of the inner hub (110), the second connecting piece (420) is arranged around an outer periphery of the first connecting piece (410), the transition piece (430) is connected between the first connecting piece (410) and the second connecting piece (420), and the transition piece (430) is inclined opposite to the rotation axis of the inner hub (110) in the air outlet direction.