Composite fan

Abstract

A composite fan includes a housing including an inlet, an outlet, a driving member, and a space; a hub disposed in the space, driven by the driving member, and including a central member and an annular base wherein the annular base includes inner and outer annular surfaces; a plurality of vertical blades secured to the inner or outer annular surface wherein a first airflow path is disposed between any two adjacent vertical blades, and each vertical blade is at an angle of 80 to 100 degrees with respect to the annular base; and a plurality of stacked, annular horizontal blades at an angle of 80 to 100 degrees with respect to the vertical blades. The horizontal blades are secured to the vertical blades, the horizontal blades are secured to the inner or outer annular surface, and a second airflow path is disposed between any two adjacent horizontal blades.

Description

FIELD OF THE INVENTION

[0001] The invention relates to mechanical fans and more particularly to a composite fan characterized by producing air flows with higher flow rate, being easy to assemble, and not obstructing the air flows.BACKGROUND OF THE INVENTION

[0002] Two popular fans are detailed below.

[0003] One is a centrifugal fan comprises a plurality of vertical blades adapted to rotate about a vertical hub (i.e., Z axis). The blades are radial and extend outward from the hub when they are viewed from a top. Air between the blades is thrown out (i.e., exits) due to centrifugal force when the fan is activated.

[0004] The other is a fan for viscous fluid and is disclosed by U.S. Pat. No. 10,920,790. Its operation principle is described below. Air is drawn into a center of a plurality of annular blades stacked along an axial direction of a hub. Air between the annular blades exits the fan as air flows due to centrifugal force. Hence, a cooling effect is generated due to the air flows. Besides, because these annular blades are parallel and spaced, several supporting columns are required to secure them. Each of the annular blades comprise a plurality of through holes, and the supporting columns pass through the through holes, respectively. However, these supporting columns increases difficulty of assembly and obstructs the air flows.

[0005] Moreover, both the centrifugal fans and the fans for viscous fluid have lower flow rates which cannot be increased by the conventional technologies.

[0006] Thus, the need for improvement still exists.SUMMARY OF THE INVENTION

[0007] It is therefore one object of the invention to provide a composite fan having advantages including producing air flows with high flow rate, being easy to assemble, and not obstructing the air flows. Particularly, the invention aims to solve the problems associated with the conventional art as follows. Both the centrifugal fans and the fans for viscous fluid have lower flow rates which cannot be increased by the conventional technologies. Regarding the fans for viscous fluid, the provision of the supporting columns not only increases difficulty of assembly but also obstructs the air flows.

[0008] For achieving above and other objects, the invention provides a composite fan comprising a housing comprising an inlet, an outlet, a driving member, and an internal space; a hub disposed in the internal space and comprising a central member, an annular base, and an axis of rotation wherein the hub is driven by the driving member for rotation, and the annular base includes an inner annular surface and an outer annular surface; a plurality of vertical blades secured to the inner annular surface or the outer annular surface wherein a first airflow path is disposed between any two adjacent ones of the plurality of vertical blades, and each vertical blade is at an angle of 80 to 100 degrees with respect to the annular base; and a plurality of horizontal blades being annular, parallel to each other, and at an angle of 80 to 100 degrees with respect to the plurality of vertical blades wherein the plurality of horizontal blades are secured to the plurality of vertical blades, the plurality of horizontal blades are secured to the inner annular surface or the outer annular surface, and a second airflow path is disposed between any two adjacent ones of the plurality of horizontal blades.

[0009] The above and other objects, features and advantages of the invention will become apparent from the following detailed description taken with the accompanying drawings.BRIEF DESCRIPTION OF DRAWINGS

[0010] FIG. 1A is a perspective view of a composite fan according to a first embodiment of the invention;

[0011] FIG. 1B is a broken-away perspective view of the composite fan;

[0012] FIG. 1C is a longitudinal sectional view of the composite fan with the left portion being greatly enlarged;

[0013] FIG. 2A is a perspective view of a composite fan according to a second embodiment of the invention;

[0014] FIG. 2B is a broken-away perspective view of the composite fan in FIG. 2A;

[0015] FIG. 2C is a longitudinal sectional view of the composite fan in FIG. 2A with the left portion being greatly enlarged;

[0016] FIG. 3A is a perspective view of a composite fan according to a third embodiment of the invention;

[0017] FIG. 3B is a broken-away perspective view of the composite fan in FIG. 3A;

[0018] FIG. 3C is a longitudinal sectional view of the composite fan in FIG. 3A with the left portion being greatly enlarged;

[0019] FIG. 4A is a perspective view of a fan according to a first conventional art;

[0020] FIG. 4B is a broken-away perspective view of the fan in FIG. 4A;

[0021] FIG. 4C is a longitudinal sectional view of the fan in FIG. 4A with the left portion being greatly enlarged;

[0022] FIG. 5A is a perspective view of a fan according to a second conventional art;

[0023] FIG. 5B is a broken-away perspective view of the fan in FIG. 5A;

[0024] FIG. 5C is a longitudinal sectional view of the fan in FIG. 5A with the left portion being greatly enlarged;

[0025] FIG. 6A is a perspective view of a fan according to a third conventional art;

[0026] FIG. 6B is a broken-away perspective view of the fan in FIG. 6A;

[0027] FIG. 6C is a longitudinal sectional view of the fan in FIG. 6A with the left portion being greatly enlarged;

[0028] FIG. 7A is a perspective view of a fan according to a fourth conventional art;

[0029] FIG. 7B is a broken-away perspective view of the fan in FIG. 7A; and

[0030] FIG. 7C is a longitudinal sectional view of the fan in FIG. 7A with the left portion being greatly enlarged.DETAILED DESCRIPTION OF THE INVENTION

[0031] Referring to FIGS. 1A, 1B and 1C, a composite fan in accordance with a first embodiment of the invention comprises the following components as discussed in detail below.

[0032] A housing 10 comprises an inlet11, an outlet 12, a driving member 13 and an internal space 14.

[0033] A hub 20 is disposed in the internal space 14 and comprises a central member 21, an annular base 22 and an axis of rotation M. The hub 20 is driven by the driving member 13 for rotation. The annular base 22 includes an inner annular surface 221 and an outer annular surface 222.

[0034] A plurality of vertical blades 30 are secured to the inner annular surface 221. The vertical blades 30 secured to the outer annular surface 222 is also possible in other embodiments. A first airflow path 31 is provided between any two adjacent ones of the vertical blades 30. Each vertical blade 30 is at an angle of 80 to 100 degrees with respect to the annular base 22. That is, the vertical blades 30 are substantially perpendicular to the annular base 22.

[0035] A plurality of horizontal blades 40 are annular, parallel to each other, and at an angle of 80 to 100 degrees with respect to the vertical blades 30. That is, the horizontal blades 40 are substantially perpendicular to the vertical blades 30. The horizontal blades 40 are secured to the vertical blades 30. The horizontal blades 40 are also secured to the outer annular surface 222. The horizontal blades 40 secured to the inner annular surface 221 is also possible in other embodiments. A second airflow path 41 is provided between any two adjacent ones of the horizontal blades 40.

[0036] In fact, the central member 21 has a height H which can be increased or decreased at a manufacturing process depending on applications.

[0037] Percentage of the inner annular surface 221 to the annular base 22 and percentage of the outer annular surface 222 to the annular base 22 can be adjusted. For example, the percentages are 50%. Alternatively, the inner annular surface 221 and the outer annular surface 222 are demarcated at a position of about half of a virtual line from an outer radius to an inner radius of the annular base 22.

[0038] Referring to FIGS. 2A, 2B and 2C, a composite fan in accordance with a second embodiment of the invention is shown. The characteristics of the second embodiment are substantially the same as that of the first embodiment except the following: the vertical blades 30 are disposed along edges of the horizontal blades 40. The vertical blades 30 are secured to the outer annular surface 222 and the horizontal blades 40 are secured to the inner annular surface 221. The horizontal blades 40 each include an annular inner edge 42. An air flows turning space P is formed between the annular inner edges 42 and the central member 21.

[0039] Referring to FIGS. 3A, 3B and 3C, a composite fan in accordance with a third embodiment of the invention is shown. The characteristics of the third embodiment are substantially the same as that of the first embodiment except the following: the annular base 22 of the hub 20 is eliminated. The vertical blades 30 are secured to the central member 21. The vertical blades 30 are at an angle of 80 to 100 degrees with respect to the central member 21. The horizontal blades 40 are secured to the vertical blades 30.

[0040] It is noted that while the annular base 22 is eliminated, the vertical blades 30 and the horizontal blades 40 are located at positions corresponding to the inner annular surface 221 (i.e., inner ring) and the outer annular surface 222 (i.e., outer ring), respectively.

[0041] Moreover, while some components are eliminated, the cooling effect of the embodiment is still very good.

[0042] Referring to FIGS. 4A, 4B and 4C, a fan 91 according to a first conventional art is shown.

[0043] Referring to FIGS. 5A, 5B and 5C, a fan 92 according to a second conventional art is shown.

[0044] Referring to FIGS. 6A, 6B and 6C, a fan 93 according to a third conventional art is shown.

[0045] Referring to FIGS. 7A, 7B and 7C, a fan 94 according to a fourth conventional art is shown.

[0046] Areas of the inner ring and the outer ring in each of the three embodiments and the four conventional arts are the same. The flow rates that are generated by the composite fans of the three embodiments are 1.65 CFM (cubic feet per minute), 1.68 CFM and 1.67 CFM, respectively after being measured.

[0047] To the contrast, the flow rates generated by the conventional fans of the four conventional arts are 1.5 CFM, 1.38 CFM, 1.38 CFM and 1.32 CFM, respectively after being measured. Therefore, their flow rates are less than that of the embodiments of the invention.

[0048] The TABLE 1-1 and TABLE 1-2 can be combined together as one Table (its left portion and its right portion) that shows the summarized comparison result of the flow rates generated by the composite fans of the three embodiments (or called as examples 1 to 3) of the invention and that of the four conventional fans (or called as examples 4 to 7).TABLE 1Example No123Inner ringVertical bladesHorizontalVertical bladesdiscsOuter ringHorizontalVertical bladesHorizontaldiscsdiscsFlow rate1.651.681.67(CFM)RemarkThis inventionThis inventionThis invention4567Vertical bladesVertical bladesHorizontalHorizontaldiscsdiscsVertical bladesN / AHorizontalN / Adiscs1.51.381.381.32ConventionalConventionalConventionalConventionalartartartart

[0049] It is found that the flow rates generated by the composite fans of the three embodiments of the invention are greater than that of the four conventional fans.

[0050] Moreover, with respect to the problems associated with the conventional art including being uneasy to assemble and obstruction of the air flows, the invention provides a composite fan having a plurality of horizontal blades secured to a plurality of vertical blades and without the provision of the conventional supporting columns. Punching holes is not required. The tedious fastening of the supporting columns is eliminated. Finally, the problem of obstructing the air flows due to the supporting columns is solved.

[0051] The invention has the following advantages and benefits in comparison with the conventional art:

[0052] Having higher flow rate. The flow rates generated by the composite fans of the three embodiments (examples 1 to 3) are 1.65 CFM, 1.68 CFM and 1.67 CFM, respectively after being measured. To the contrast, flow rates generated by the conventional fans of the four examples (examples 4 to 7) are 1.5 CFM, 1.38 CFM, 1.38 CFM and 1.32 CFM, respectively after being measured. As a result, the invention has a higher flow rate.

[0053] Easy assembly and no obstruction of air flows. The invention provides a composite fan having a plurality of horizontal blades secured to a plurality of vertical blades and without the provision of the conventional supporting columns. Punching holes is not required. The fastening of the supporting columns is eliminated. In addition, the problem of obstructing the air flows due to the supporting columns is solved. Thus, the invention effectuates an easy assembly and there is no problem of obstructing the air flows.

Examples

Embodiment Construction

[0031]Referring to FIGS. 1A, 1B and 1C, a composite fan in accordance with a first embodiment of the invention comprises the following components as discussed in detail below.

[0032]A housing 10 comprises an inlet11, an outlet 12, a driving member 13 and an internal space 14.

[0033]A hub 20 is disposed in the internal space 14 and comprises a central member 21, an annular base 22 and an axis of rotation M. The hub 20 is driven by the driving member 13 for rotation. The annular base 22 includes an inner annular surface 221 and an outer annular surface 222.

[0034]A plurality of vertical blades 30 are secured to the inner annular surface 221. The vertical blades 30 secured to the outer annular surface 222 is also possible in other embodiments. A first airflow path 31 is provided between any two adjacent ones of the vertical blades 30. Each vertical blade 30 is at an angle of 80 to 100 degrees with respect to the annular base 22. That is, the vertical blades 30 are substantially perpendicu...

FIELD OF THE INVENTION

[0001] The invention relates to mechanical fans and more particularly to a composite fan characterized by producing air flows with higher flow rate, being easy to assemble, and not obstructing the air flows.BACKGROUND OF THE INVENTION

[0002] Two popular fans are detailed below.

[0003] One is a centrifugal fan comprises a plurality of vertical blades adapted to rotate about a vertical hub (i.e., Z axis). The blades are radial and extend outward from the hub when they are viewed from a top. Air between the blades is thrown out (i.e., exits) due to centrifugal force when the fan is activated.

[0004] The other is a fan for viscous fluid and is disclosed by U.S. Pat. No. 10,920,790. Its operation principle is described below. Air is drawn into a center of a plurality of annular blades stacked along an axial direction of a hub. Air between the annular blades exits the fan as air flows due to centrifugal force. Hence, a cooling effect is generated due to the air flows. Besides, because these annular blades are parallel and spaced, several supporting columns are required to secure them. Each of the annular blades comprise a plurality of through holes, and the supporting columns pass through the through holes, respectively. However, these supporting columns increases difficulty of assembly and obstructs the air flows.

[0005] Moreover, both the centrifugal fans and the fans for viscous fluid have lower flow rates which cannot be increased by the conventional technologies.

[0006] Thus, the need for improvement still exists.SUMMARY OF THE INVENTION

[0007] It is therefore one object of the invention to provide a composite fan having advantages including producing air flows with high flow rate, being easy to assemble, and not obstructing the air flows. Particularly, the invention aims to solve the problems associated with the conventional art as follows. Both the centrifugal fans and the fans for viscous fluid have lower flow rates which cannot be increased by the conventional technologies. Regarding the fans for viscous fluid, the provision of the supporting columns not only increases difficulty of assembly but also obstructs the air flows.

[0008] For achieving above and other objects, the invention provides a composite fan comprising a housing comprising an inlet, an outlet, a driving member, and an internal space; a hub disposed in the internal space and comprising a central member, an annular base, and an axis of rotation wherein the hub is driven by the driving member for rotation, and the annular base includes an inner annular surface and an outer annular surface; a plurality of vertical blades secured to the inner annular surface or the outer annular surface wherein a first airflow path is disposed between any two adjacent ones of the plurality of vertical blades, and each vertical blade is at an angle of 80 to 100 degrees with respect to the annular base; and a plurality of horizontal blades being annular, parallel to each other, and at an angle of 80 to 100 degrees with respect to the plurality of vertical blades wherein the plurality of horizontal blades are secured to the plurality of vertical blades, the plurality of horizontal blades are secured to the inner annular surface or the outer annular surface, and a second airflow path is disposed between any two adjacent ones of the plurality of horizontal blades.

[0009] The above and other objects, features and advantages of the invention will become apparent from the following detailed description taken with the accompanying drawings.BRIEF DESCRIPTION OF DRAWINGS

[0010] FIG. 1A is a perspective view of a composite fan according to a first embodiment of the invention;

[0011] FIG. 1B is a broken-away perspective view of the composite fan;

[0012] FIG. 1C is a longitudinal sectional view of the composite fan with the left portion being greatly enlarged;

[0013] FIG. 2A is a perspective view of a composite fan according to a second embodiment of the invention;

[0014] FIG. 2B is a broken-away perspective view of the composite fan in FIG. 2A;

[0015] FIG. 2C is a longitudinal sectional view of the composite fan in FIG. 2A with the left portion being greatly enlarged;

[0016] FIG. 3A is a perspective view of a composite fan according to a third embodiment of the invention;

[0017] FIG. 3B is a broken-away perspective view of the composite fan in FIG. 3A;

[0018] FIG. 3C is a longitudinal sectional view of the composite fan in FIG. 3A with the left portion being greatly enlarged;

[0019] FIG. 4A is a perspective view of a fan according to a first conventional art;

[0020] FIG. 4B is a broken-away perspective view of the fan in FIG. 4A;

[0021] FIG. 4C is a longitudinal sectional view of the fan in FIG. 4A with the left portion being greatly enlarged;

[0022] FIG. 5A is a perspective view of a fan according to a second conventional art;

[0023] FIG. 5B is a broken-away perspective view of the fan in FIG. 5A;

[0024] FIG. 5C is a longitudinal sectional view of the fan in FIG. 5A with the left portion being greatly enlarged;

[0025] FIG. 6A is a perspective view of a fan according to a third conventional art;

[0026] FIG. 6B is a broken-away perspective view of the fan in FIG. 6A;

[0027] FIG. 6C is a longitudinal sectional view of the fan in FIG. 6A with the left portion being greatly enlarged;

[0028] FIG. 7A is a perspective view of a fan according to a fourth conventional art;

[0029] FIG. 7B is a broken-away perspective view of the fan in FIG. 7A; and

[0030] FIG. 7C is a longitudinal sectional view of the fan in FIG. 7A with the left portion being greatly enlarged.DETAILED DESCRIPTION OF THE INVENTION

[0031] Referring to FIGS. 1A, 1B and 1C, a composite fan in accordance with a first embodiment of the invention comprises the following components as discussed in detail below.

[0032] A housing 10 comprises an inlet11, an outlet 12, a driving member 13 and an internal space 14.

[0033] A hub 20 is disposed in the internal space 14 and comprises a central member 21, an annular base 22 and an axis of rotation M. The hub 20 is driven by the driving member 13 for rotation. The annular base 22 includes an inner annular surface 221 and an outer annular surface 222.

[0034] A plurality of vertical blades 30 are secured to the inner annular surface 221. The vertical blades 30 secured to the outer annular surface 222 is also possible in other embodiments. A first airflow path 31 is provided between any two adjacent ones of the vertical blades 30. Each vertical blade 30 is at an angle of 80 to 100 degrees with respect to the annular base 22. That is, the vertical blades 30 are substantially perpendicular to the annular base 22.

[0035] A plurality of horizontal blades 40 are annular, parallel to each other, and at an angle of 80 to 100 degrees with respect to the vertical blades 30. That is, the horizontal blades 40 are substantially perpendicular to the vertical blades 30. The horizontal blades 40 are secured to the vertical blades 30. The horizontal blades 40 are also secured to the outer annular surface 222. The horizontal blades 40 secured to the inner annular surface 221 is also possible in other embodiments. A second airflow path 41 is provided between any two adjacent ones of the horizontal blades 40.

[0036] In fact, the central member 21 has a height H which can be increased or decreased at a manufacturing process depending on applications.

[0037] Percentage of the inner annular surface 221 to the annular base 22 and percentage of the outer annular surface 222 to the annular base 22 can be adjusted. For example, the percentages are 50%. Alternatively, the inner annular surface 221 and the outer annular surface 222 are demarcated at a position of about half of a virtual line from an outer radius to an inner radius of the annular base 22.

[0038] Referring to FIGS. 2A, 2B and 2C, a composite fan in accordance with a second embodiment of the invention is shown. The characteristics of the second embodiment are substantially the same as that of the first embodiment except the following: the vertical blades 30 are disposed along edges of the horizontal blades 40. The vertical blades 30 are secured to the outer annular surface 222 and the horizontal blades 40 are secured to the inner annular surface 221. The horizontal blades 40 each include an annular inner edge 42. An air flows turning space P is formed between the annular inner edges 42 and the central member 21.

[0039] Referring to FIGS. 3A, 3B and 3C, a composite fan in accordance with a third embodiment of the invention is shown. The characteristics of the third embodiment are substantially the same as that of the first embodiment except the following: the annular base 22 of the hub 20 is eliminated. The vertical blades 30 are secured to the central member 21. The vertical blades 30 are at an angle of 80 to 100 degrees with respect to the central member 21. The horizontal blades 40 are secured to the vertical blades 30.

[0040] It is noted that while the annular base 22 is eliminated, the vertical blades 30 and the horizontal blades 40 are located at positions corresponding to the inner annular surface 221 (i.e., inner ring) and the outer annular surface 222 (i.e., outer ring), respectively.

[0041] Moreover, while some components are eliminated, the cooling effect of the embodiment is still very good.

[0042] Referring to FIGS. 4A, 4B and 4C, a fan 91 according to a first conventional art is shown.

[0043] Referring to FIGS. 5A, 5B and 5C, a fan 92 according to a second conventional art is shown.

[0044] Referring to FIGS. 6A, 6B and 6C, a fan 93 according to a third conventional art is shown.

[0045] Referring to FIGS. 7A, 7B and 7C, a fan 94 according to a fourth conventional art is shown.

[0046] Areas of the inner ring and the outer ring in each of the three embodiments and the four conventional arts are the same. The flow rates that are generated by the composite fans of the three embodiments are 1.65 CFM (cubic feet per minute), 1.68 CFM and 1.67 CFM, respectively after being measured.

[0047] To the contrast, the flow rates generated by the conventional fans of the four conventional arts are 1.5 CFM, 1.38 CFM, 1.38 CFM and 1.32 CFM, respectively after being measured. Therefore, their flow rates are less than that of the embodiments of the invention.

[0048] The TABLE 1-1 and TABLE 1-2 can be combined together as one Table (its left portion and its right portion) that shows the summarized comparison result of the flow rates generated by the composite fans of the three embodiments (or called as examples 1 to 3) of the invention and that of the four conventional fans (or called as examples 4 to 7).TABLE 1Example No123Inner ringVertical bladesHorizontalVertical bladesdiscsOuter ringHorizontalVertical bladesHorizontaldiscsdiscsFlow rate1.651.681.67(CFM)RemarkThis inventionThis inventionThis invention4567Vertical bladesVertical bladesHorizontalHorizontaldiscsdiscsVertical bladesN / AHorizontalN / Adiscs1.51.381.381.32ConventionalConventionalConventionalConventionalartartartart

[0049] It is found that the flow rates generated by the composite fans of the three embodiments of the invention are greater than that of the four conventional fans.

[0050] Moreover, with respect to the problems associated with the conventional art including being uneasy to assemble and obstruction of the air flows, the invention provides a composite fan having a plurality of horizontal blades secured to a plurality of vertical blades and without the provision of the conventional supporting columns. Punching holes is not required. The tedious fastening of the supporting columns is eliminated. Finally, the problem of obstructing the air flows due to the supporting columns is solved.

[0051] The invention has the following advantages and benefits in comparison with the conventional art:

[0052] Having higher flow rate. The flow rates generated by the composite fans of the three embodiments (examples 1 to 3) are 1.65 CFM, 1.68 CFM and 1.67 CFM, respectively after being measured. To the contrast, flow rates generated by the conventional fans of the four examples (examples 4 to 7) are 1.5 CFM, 1.38 CFM, 1.38 CFM and 1.32 CFM, respectively after being measured. As a result, the invention has a higher flow rate.

[0053] Easy assembly and no obstruction of air flows. The invention provides a composite fan having a plurality of horizontal blades secured to a plurality of vertical blades and without the provision of the conventional supporting columns. Punching holes is not required. The fastening of the supporting columns is eliminated. In addition, the problem of obstructing the air flows due to the supporting columns is solved. Thus, the invention effectuates an easy assembly and there is no problem of obstructing the air flows.

Examples

Embodiment Construction

[0031]Referring to FIGS. 1A, 1B and 1C, a composite fan in accordance with a first embodiment of the invention comprises the following components as discussed in detail below.

[0032]A housing 10 comprises an inlet11, an outlet 12, a driving member 13 and an internal space 14.

[0033]A hub 20 is disposed in the internal space 14 and comprises a central member 21, an annular base 22 and an axis of rotation M. The hub 20 is driven by the driving member 13 for rotation. The annular base 22 includes an inner annular surface 221 and an outer annular surface 222.

[0034]A plurality of vertical blades 30 are secured to the inner annular surface 221. The vertical blades 30 secured to the outer annular surface 222 is also possible in other embodiments. A first airflow path 31 is provided between any two adjacent ones of the vertical blades 30. Each vertical blade 30 is at an angle of 80 to 100 degrees with respect to the annular base 22. That is, the vertical blades 30 are substantially perpendicu...

Claims

1. A composite fan, comprising:a housing comprising an inlet, an outlet, a driving member, and an internal space;a hub disposed in the internal space and comprising a central member, an annular base, and an axis of rotation wherein the hub is driven by the driving member for rotation, and the annular base includes an inner annular surface and an outer annular surface;a plurality of vertical blades secured to the inner annular surface or the outer annular surface wherein a first airflow path is disposed between any two adjacent ones of the plurality of vertical blades, and each vertical blade is at an angle of 80 to 100 degrees with respect to the annular base; anda plurality of horizontal blades being annular, parallel to each other, and at an angle of 80 to 100 degrees with respect to the plurality of vertical blades wherein the plurality of horizontal blades are secured to the plurality of vertical blades, the plurality of horizontal blades are secured to the inner annular surface or the outer annular surface, and a second airflow path is disposed between any two adjacent ones of the plurality of horizontal blades.

2. The composite fan of claim 1, wherein the plurality of vertical blades are secured to the inner annular surface and the plurality of horizontal blades are secured to the outer annular surface.

3. The composite fan of claim 1, wherein the plurality of vertical blades are secured to the outer annular surface, the plurality of horizontal blades are secured to the inner annular surface, the plurality of horizontal blades each include an annular inner edge, and an air flows turning space is formed between the annular inner edges and the central member.

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