Multiple Fan Blade Angles in a Single Crossflow Fan

Abstract

A fan may be provided. The fan may comprise a first plurality of vanes and a second plurality of vanes. The first plurality of vanes may be arranged substantially parallel to an axis of rotation and positioned along a first arc substantially centered on the axis of rotation. Vanes in the first plurality of vanes may be being positioned at a first angle relative to the first arc. The second plurality of vanes may be arranged substantially parallel to the axis of rotation and positioned along a second arc substantially centered on the axis of rotation. Vanes in the second plurality of vanes may be positioned at a second angle relative to the second arc. The first angle may be different than the second angle.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The current application is related to U.S. patent application Ser. No. 13/338,287 filed on Dec. 28, 2011, entitled "Vented Fan Duct," (Attorney Docket No. Al214H), and U.S. patent application Ser. No. ______ filed on Dec. 28, 2011, entitled "Adjusting Air Flow without Restricting a Fan," (Attorney Docket No. Al226H), which are hereby incorporated by reference in its entirety.

BACKGROUND

[0002] Equipment such as, for example, agricultural machines, may have a fan. The fan may be used to create airflow. The airflow may be used for various purposes such as, for example, cleaning and cooling equipment parts. The fan may be internal or external.

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate various embodiments of the disclosure. In the drawings:

[0004] FIG. 1 is a diagram of a combine;

[0005] FIG. 2 is a diagram of a fan assembly;

[0006] FIG. 3 is a diagram of a fan; and

[0007] FIG. 4 is a cross-section of the fan.

DETAILED DESCRIPTION

Overview

[0008] A fan may be provided. The fan may comprise a first plurality of vanes and a second plurality of vanes. The first plurality of vanes may be arranged substantially parallel to an axis of rotation and positioned along a first arc substantially centered on the axis of rotation. Vanes in the first plurality of vanes may be being positioned at a first angle relative to the first arc. The second plurality of vanes may be arranged substantially parallel to the axis of rotation and positioned along a second arc substantially centered on the axis of rotation. Vanes in the second plurality of vanes may be positioned at a second angle relative to the second arc. The first angle may be different than the second angle.

[0009] Both the foregoing general description and the following detailed description are examples and explanatory only, and should not be considered to restrict the disclosure's scope, as described and claimed. Further, features and/or variations may be provided in addition to those set forth herein. For example, embodiments of the disclosure may be directed to various feature combinations and sub-combinations described in the detailed description.

EXAMPLE EMBODIMENTS

[0010] The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar elements. While embodiments of the invention may be described, modifications, adaptations, and other implementations are possible. For example, substitutions, additions, or modifications may be made to the elements illustrated in the drawings, and the methods described herein may be modified by substituting, reordering, or adding stages to the disclosed methods. Accordingly, the following detailed description does not limit the invention. Instead, the proper scope of the invention is defined by the appended claims.

[0011] An agricultural machine (e.g. a combine) may include a fan. The fan may be used to create airflow. The airflow may be used for various purposes such as, for example, cleaning and cooling equipment parts. With embodiments of the disclosure, the fan may produce a pulsating airflow pattern.

[0012] Fans may comprise vanes (e.g., fan blades or airfoils). With conventional fans, the vanes may all be positioned at a single angle. This may produce a steady air stream at a constant velocity. At various times, however, it may be desirable for a fan's outlet airflow pattern to pulsate. Consistent with embodiments of the disclosure, to achieve a pulsating airflow, while maintaining a constant fan speed, the vanes may be positioned at different angles. Velocity inconsistencies in the fan's outlet airflow pattern (i.e., pulsation) may be adjusted by increasing or decreasing the angle differences amongst the various vanes. In other words, the angles between the various vanes may be constant or adjustable. For example, the airflow pattern produced by the fan may be adjusted by adjusting the various angles between the various vanes. In addition, the various angles between the various vanes may be adjustable in real-time (i.e., when the fan is rotating) or when the fan is stationary (i.e., when the fan is not rotating).

[0013] FIG. 1 is a diagram of a combine 100. Combine 100 may comprise a separator housing 102, an operator's work station and cab 104, a grain tank 106, and an elevator assembly 108. A swingable unloading auger assembly 110 may pivot to a position extending laterally outward to one side of combine 100 to unload grain tank 106. Unloading auger assembly 110 may swing inward to a storage position as shown in FIG. 1 when grain tank 106 is not being unloaded.

[0014] Elevator assembly 108 may have a conveyor 112 mounted in an elevator housing 114. Conveyor 112 may be trained around rear drive sprockets 116 and a front drum 118. Hydraulic linear actuators 120 may pivot elevator housing 114 to raise and lower the forward end of elevator housing 114.

[0015] Crop material may be fed to a feed beater 122 by conveyor 112 in elevator housing 114. Feed beater 122 may feed crop material to a separating rotor 124. Separating rotor 124 may comprise a feed section 126, a threshing section 128, and a separation section 130. Feed section 126 may move crop material in a spiral path about a generally horizontal fore and aft axis of rotation to separating rotor 124, toward threshing section 128. In threshing section 128, crop material may pass between a cylinder bar 132 and a concave 134 where grain may be threshed. Threshed grain that is not separated by concave 134 may be separated in separation section 130 and may pass through a separation grate 136. A grain pan 138 may convey grain and chaff forward and may deposit it on a chaffer 140. Crop material other than grain (MOG) may be discharged from separating rotor 124 through a rotor discharge 142.

[0016] Grain and MOG that may pass through concave 134 and separation grate 136 may fall to upper grain pan 138. Grain pan 138 may convey grain and chaff forward and may deposit it on chaffer 140. The grain may be cleaned by chaffer 140 and a sieve 144 and air from a fan assembly 146. Chaff may be discharged from the rear of sieve 144 and chaffer 140. Clean grain may fall into a clean grain auger 148. The clean grain may be conveyed to grain tank 106 by clean grain auger 148 and an elevator (not shown). Tailings may fall into a returns auger 150 and may be conveyed to separating rotor 124 by returns auger and return elevators (not shown), where they may be threshed a second time.

[0017] FIG. 2 is a diagram of fan assembly 146. Fan assembly 146 may comprise a duct 202 and a fan 204. Duct 202 may comprise a wall 206. Wall 206 may define a passage and/or a cavity 208. Fan 204 may be located in cavity 208. Cavity 208 may be in fluid communication with an inlet 210 and an outlet 212. Outlet 212 may be arranged to allow a fluid (e.g., air) to be at least partially directed toward sieve 144.

[0018] FIG. 3 is a diagram of fan 204. Fan 204 may comprise a first section 302 and a second section 304. First section 302 and second section 304 may be separated by a mounting member 306. First section 302 may comprise a first band 308 and a second band 310. Second section 304 may comprise second band 310 and a third band 312. First section 302 and second section 304 may be centered on an axis of rotation 314.

[0019] First section 302 and second section 304 may comprise any number of vanes from a plurality of vanes 316. Plurality of vanes 316 may be arranged substantially parallel to axis of rotation 314. In addition, first band 308 and second band 310 may be absent in various embodiments. For example, plurality of vanes 316 may be attached directly to mounting member 306. Mounting member 306 may be orthogonal to axis of rotation 314.

[0020] While FIG. 3 shows plurality of vanes 316 located at one location along axis of rotation 314, embodiments may comprise plurality of vanes 316 located at varying positions along the axis of rotation. For example, the vanes located in first section 302 may be located a first distance from mounting member 306 and the vanes located in second section 304 may be located a second distance from mounting member 306. In addition, the vanes located in first section 302 may have a different length than the vanes located in second section 304. Furthermore, the various vanes comprising plurality of vanes 316 may have similar geometries or differing geometries. Examples of geometries may include a flat profile, a concave profile, a convex profile, and an airfoil profile. For instance, the vanes located in first section 302 may have a concave profile and the vanes located in second section 304 may have a convex profile.

[0021] FIG. 4 is a cross-section of fan 204. To avoid cluttering FIG. 4 only eight vanes are shown. However, embodiments may comprise any number of vanes. The vanes may be positioned at differing angles with respect to a plurality of arcs (e.g., a first arc AB, a second arc BC, a third arc CD, and a fourth arc DA).

[0022] First arc AB may comprise a first plurality of vanes (represented by a first vane 402 and a second vane 404). The first plurality of vanes may be positioned at a first angle .alpha. relative to first arc AB. Second arc BC may comprise a second plurality of vanes (represented by a third vane 406). The second plurality of vanes may be positioned at a second angle .beta. relative to second arc BC. Third arc CD may comprise a third plurality of vanes (represented by a fourth vane 408, a fifth vane 410, and a sixth vane 412). The third plurality of vanes may be positioned at a third angle .theta. relative to third arc CD. Fourth arc DA may comprise a fourth plurality of vanes (represented by a seventh vane 414 and an eighth vane 416). The fourth plurality of vanes may be positioned at a fourth angle .phi. relative to fourth arc DA.

[0023] While FIGS. 3 and 4 show first arc AB, second arc BC, third arc CD, and fourth arc DA having different lengths, embodiments may comprise arcs of equal length. For example, first arc AB may occupy quadrant I, second arc BC may occupy quadrant II, third arc CD may occupy quadrant III, and fourth arc DA may occupy quadrant IV. In addition, fan 204 may contain any number of arcs. Furthermore, a radial distance of each arc may be different. For example, first arc AB may be located a first distance (e.g., six-inches) from axis of rotation 314 and second arc BC may be located a second distance (e.g., nine-inches) from axis of rotation 314.

[0024] Furthermore, first angle .alpha., second angle .beta., third angle .theta., and fourth angle .phi. may be fixed or adjustable. For example, fan 204 may comprise first arc AB occupying quadrants I and II and having a plurality of vanes at first angle .alpha.. Fan 204 also may comprise second arc BC occupying quadrants III and IV and having a plurality of vanes at second angle .beta..

[0025] A vane's angle relative to an arc may be adjustable. Moreover, first angle .alpha., second angle .beta., third angle .theta., and fourth angle .phi. may be adjusted and may cause an airflow exiting outlet 214 to have an oscillating velocity profile. In other words, the airflow exiting outlet 214 may pulsate. For example, first angle .alpha., second angle .beta., third angle .theta., and fourth angle .phi. may be adjusted prior to using combine 100 to achieve a desired airflow pattern. In addition, first angle .alpha., second angle .beta., third angle .theta., and fourth angle .phi. may be adjusted while combine 100 is in use to achieve a desired airflow pattern or to change from a first airflow pattern to a second airflow pattern.

[0026] An embodiment may comprise an apparatus. The apparatus may comprise a first plurality of vanes arranged substantially parallel to an axis of rotation. The first plurality of vanes may be positioned along a first arc substantially centered on the axis of rotation. In addition, the fan may comprise a second plurality of vanes arranged substantially parallel to the axis of rotation. The second plurality of vanes may be positioned along a second arc substantially centered on the axis of rotation. The vanes in the first plurality of vanes may be positioned at a first angle relative to the first arc. The vanes in the second plurality of vanes may be positioned at a second angle relative to the second arc. The first angle may be different than the second angle.

[0027] Another embodiment may comprise an apparatus. The apparatus may comprise a combine having a sieve and a fan arranged to direct a gas at least partially toward the sieve. The fan may comprise a first plurality of vanes arranged substantially parallel to an axis of rotation. The vanes in the first plurality of vanes may be positioned a first radius from the center of the axis of rotation. The fan may also comprise a second plurality of vanes arranged substantially parallel to the axis of rotation. The vanes in the second plurality of vanes may be positioned a second radius from the center of the axis of rotation. The vanes in the first plurality of vanes may be positioned at a first angle of attack and the vanes in the second plurality of vanes may be positioned at a second angle of attack. The first angle of attack may be different than the second angle of attack.

[0028] Yet another embodiment may comprise a method. The method may comprise: rotating a first plurality of vanes about an axis of rotation, rotating a second plurality of vanes about the axis of rotation, and creating a desired airflow pattern in response to rotating the first plurality of vanes and the second plurality of vanes about the axis or rotation. The first plurality of vanes may be arranged at a first angle relative to the axis of rotation. The second plurality of vanes may be arranged at a second angle relative to the axis of rotation. The second angle relative to the axis of rotation may be different than the first angle relative to the axis of rotation.

[0029] Both the foregoing general description and the following detailed description are examples and explanatory only, and should not be considered to restrict the invention's scope, as described and claimed. Further, features and/or variations may be provided in addition to those set forth herein. For example, embodiments may be directed to various feature combinations and sub-combinations described herein.

[0030] All rights, including copyrights, in the code included herein are vested in and the property of the Applicant. The Applicant retains and reserves all rights in the code included herein, and grants permission to reproduce the material only in connection with reproduction of the granted patent and for no other purpose.

[0031] While the specification includes examples, the invention's scope is indicated by the following claims. Furthermore, while the specification has been described in language specific to structural features and/or methodological acts, the claims are not limited to the features or acts described above. Rather, the specific features and acts described above are disclosed as example embodiments.

Claims

1. An apparatus comprising: a first plurality of vanes arranged substantially parallel to an axis of rotation and positioned along a first arc substantially centered on the axis of rotation, the vanes in the first plurality of vanes being positioned at a first angle relative to the first arc; and a second plurality of vanes arranged substantially parallel to the axis of rotation and positioned along a second arc substantially centered on the axis of rotation, the vanes in the second plurality of vanes being positioned at a second angle relative to the second arc, the first angle being different than the second angle.

2. The apparatus of claim 1, wherein the first arc and the second arc form part of a same circle.

3. The apparatus claim 1, wherein the first plurality of vanes and the second plurality of vanes have different positions along a length of the axis of rotation.

4. The apparatus of claim 1, further comprising a mounting member substantially orthogonal to the axis of rotation, the first plurality of vanes and the second plurality of vanes operably coupled to the mounting member.

5. The apparatus of claim 1, further comprising: a duct having a wall, the wall defining a passage; an inlet in fluid communication with the passage; and an outlet in fluid communication with the passage, wherein the first plurality of vanes and the second plurality of vanes are arranged to propel a fluid into the inlet.

6. The apparatus of claim 5, further comprising a housing having an inter surface, the interior surface defining a cavity and an exhaust, the exhaust in fluid communication with the inlet, the first plurality of vanes and the second plurality of vanes are arranged substantially inside the cavity.

7. The apparatus of claim 1, further comprising a third plurality of vanes arranged substantially parallel to the axis of rotation and positioned along a third arc substantially centered on the axis of rotation, the vanes in the third plurality of vanes being positioned at a third angle relative to the third arc, the third angle being different than the first angle and the second angle.

8. The apparatus of claim 1, wherein the first angle relative to the first arc is configured to be adjustable and the second angle relative to the second arc is configured to be adjustable.

9. The apparatus of claim 1, wherein the first angle relative to the first arc and the second angle relative to the second arc are configured to cause an airflow pattern to pulsate.

10. An apparatus comprising: a combine having a sieve; and a fan arranged to direct a gas at least partially toward the sieve, the fan comprising: a first plurality of vanes arranged substantially parallel to an axis of rotation, the vanes in the first plurality of vanes positioned a first radius from the center of the axis of rotation, the vanes in the first plurality of vanes being positioned at a first angle of attack; and a second plurality of vanes arranged substantially parallel to the axis of rotation the vanes in the second plurality of vanes positioned a second radius from the center of the axis of rotation, the vanes in the second plurality of vanes being positioned at a second angle of attack, the first angle of attack being different than the second angle of attack.

11. The apparatus of claim 10, wherein the first radius is substantially equal to the second radius.

12. The apparatus claim 10, wherein the first plurality of vanes and the second plurality of vanes have different positions along a length of the axis of rotation.

13. The apparatus of claim 10, further comprising a mounting member substantially orthogonal to the axis of rotation, the first plurality of vanes and the second plurality of vanes operably coupled to the mounting member.

14. The apparatus of claim 10, further comprising: a duct having a wall, the wall defining a passage; an inlet in fluid communication with the passage; and an outlet in fluid communication with the passage, wherein the fan arranged to direct the gas at least partially toward the sieve comprises the fan arranged to direct the gas into the inlet, through the passage, and out the outlet, the outlet arranged to direct the gas at least partially toward the sieve.

15. The apparatus of claim 14, further comprising a housing having an inter surface, the interior surface defining a cavity and an exhaust, the exhaust in fluid communication with the inlet, the fan located substantially inside the cavity.

16. The apparatus of claim 10, further comprising a third plurality of vanes arranged substantially parallel to the axis of rotation and positioned along a third radius from the center of the axis of rotation, the vanes in the third plurality of vanes being positioned at a third angle of attack, the third angle of attack being different than the first angle of attack and the second angle of attack.

17. The apparatus of claim 10, the first angle of attack and the second angle of attack are configured to cause an airflow pattern to pulsate.

18. A method comprising: rotating a first plurality of vanes about an axis of rotation, the first plurality of vanes arranged at a first angle relative to the axis of rotation; rotating a second plurality of vanes about the axis of rotation, the second plurality of vanes arranged at a second angle relative to the axis of rotation, the second angle relative to the axis of rotation being different than the first angle relative to the axis of rotation; and creating a desired airflow pattern in response to rotating the first plurality of vanes and the second plurality of vanes about the axis or rotation.

19. The method of claim 18, wherein creating the desired airflow pattern comprises creating a pulsating airflow pattern.

20. The method of claim 18, wherein creating the desired airflow pattern comprises creating a uniform airflow pattern.