Patent Application
20190041073
The present invention relates generally to the field of energy capture systems, and in particular to an air flow energy capture system.
Furnace and air circulation systems most commonly employ centrifugal fans, also known as squirrel cage fans or blowers, to draw air into the system and to move the air through at a constant speed. Air is drawn into the fan through an inlet in the side of the housing, then turns 90 degrees and is accelerated with centrifugal force as it passes over the fan blades and exits the fan through an outlet in the housing. As air is drawn into the fan through the inlet, the air increases in speed, creating a draft at the inlet, both within and outside of the fan housing.
According to a first embodiment of the present invention there is disclosed a apparatus for capturing airflow from an inlet of a fan the apparatus comprising a capture fan located upstream of the centrifugal fan and an electrical generator motor operably connected to and drive by rotation of the capture fan wherein the capture fan is rotatable in a first direction by air drawn into the fan inlet during operation of the fan. The capture fan may be located in a cabinet wall surrounding the fan.
The fan may comprise a centrifugal fan, the centrifugal fan having a housing containing an impeller rotatable about a fan axis and an inlet passing through the housing along the centrifugal fan axis, the apparatus may further comprise a frame securable to the centrifugal fan housing across the centrifugal fan inlet. The capture fan may be rotatably supported by the frame wherein the capture fan has a center of rotation about the centrifugal fan axis and wherein the capture fan may be rotatable in a first direction about the centrifugal fan axis by air drawn into the centrifugal fan inlet during operation of the centrifugal fan.
The capture fan may comprise an axial fan having a central hub and a plurality of fan blades extending radially therefrom. The plurality of fan blades of the axial fan may comprise radial fan blades extending radially outward from the hub to a tip region. Each of the plurality of fan blades may have a leading and a trailing edge. The leading edge may be convex. The trailing edge may be concave. The tip region of the radial fan blades may be secured to a cylindrical outer band. Each of the plurality of fan blades may be skewed rearwardly from the leading edge to the trailing edge.
According to a further embodiment of the present invention there is disclosed a fan system for capturing airflow comprising a powered fan, a capture fan located upstream of the powered fan and an electrical generator motor operably connected to and drive by rotation of the capture fan wherein the capture fan is rotatable in a first direction by air drawn into the fan inlet during operation of the powered fan. The capture fan is located within a cabinet wall of a cabinet containing the powered fan.
The powered fan may comprise a centrifugal fan having a centrifugal fan housing wherein the fan system may further comprise a frame adapted to span an inlet in the centrifugal fan housing and securable to the centrifugal fan housing. The capture fan may have a center of rotation about a capture fan axis at the capture fan center, the capture fan rotatably mounted to the frame wherein the capture fan may be rotatable in a first direction about the capture fan axis by air drawn into the inlet during operation of the centrifugal fan.
The capture fan may comprise an axial fan having a hub at the capture fan center and a plurality of fan blades. The plurality of fan blades of the axial fan may comprise radial fan blades extending radially outward from the hub to a tip region. The tip region of the radial fan blades may be secured to a cylindrical outer band.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
In drawings which illustrate embodiments of the invention wherein similar characters of reference denote corresponding parts in each view,
Referring to
The apparatus 10 comprises an electrical generator motor 12 mounted to a frame 30 and coupled to an axial capture fan 50 along a central axis 100. The frame 30 is mounted to the centrifugal fan 8 over the inlet 6.
Referring to
As illustrated, four support arms 36 extend in an x-shape from the center ring portion 34, although it will be appreciated that more or less support arms 36 may be useful, as well. A mounting hole 42 extends along an axis spaced apart and parallel to the central axis 100 through each support arm 36 proximate to the distal end 38. The length of the support arms 36 is selected such that the frame 30 spans across the inlet 6 of the centrifugal fan 8 with the mounting holes 42 aligned with matching mounting holes 44 on the centrifugal fan 8.
The electrical generator motor 12 includes mounting feet 14, as illustrated in
Turning to
Each fan blade 54 extends radially between a root region 60 secured to the cylindrical wall portion 72 of the hub 52 and a tip region 62 secured to the outer ring 56. The fan blades 54 are joined to the cylindrical wall portion 72 of the hub 52 at the root region 60 over the full width of each blade and are joined to the outer ring 56 at the tip region 62 over the full width of each blade. Each fan blade 54 includes a convex leading edge 64 and a concave trailing edge 66. As best seen in
To assemble the apparatus 10, the electrical generator motor 12 is secured to the frame 30 as outlined above. The frame 30 is secured to the centrifugal fan 8 with fasteners 98 through the mounting holes 42 and 44. The fasteners 98 may be of any suitable type, such as, by way of non-limiting example, screws or nuts and bolts. A threaded coupling 90 with internal threading adapted to engage the external threading 18 on the driveshaft 16 is coupled to the driveshaft 16 and to a fastener 92 through the aperture 58 in the axial capture fan 50, thereby securing the axial capture fan 50 to the driveshaft 16 of the electrical generator motor 12. The fastener 92 includes external threading 94 adapted to engage with the internal threading of the treading coupling 90 and includes a head portion 96 sized to span the aperture 58 and engage upon the circular portion 70 of the hub 52.
Referring to
Turning now to
Turning now to
In some embodiments, the fan blade assembly housing 306 has an inner diameter 320 of about 6 inches. In some embodiments, the fan blade assembly housing 306 has an inner diameter 320 between about 4 inches and 8 inches. In some embodiments, a fan hub 302 has a diameter 330 of about 11 inches. In some embodiments, a fan hub 302 has a diameter 330 between about 8 inches and 20 inches. In some embodiments, the width 340 of the plurality of first fan blades 310 is about 5⅞ inches. In some embodiments, the width 314 of the plurality of first fan blades 122 is between about 4 inches 10 inches. In some embodiments, the first fan blade assembly 300 has a diameter 350 of about 23 inches. In some embodiments, the first fan blade assembly 300 has a diameter 350 between about 18 inches and 24 inches.
As illustrated, the first side of a first fan blade assembly 300 has a clockwise rotation of 322, and each first fan blades 310 has a fan blade tailing edge 312 and a fan blade leading edge 314 with a pitch angle of about 40 degrees and 9 fan blades. In some embodiments, each fan blades 310 has a fan blade tailing edge 312 and a fan blade leading edge 314 with a pitch angle between about 20 degrees and 60 degrees and between about 4 and 20 first fan blades. In some embodiments, the vertical between the fan blade tailing edge 312 and the fan blade leading edge 314 is about 2¼ inches. In some embodiments, the vertical between the fan blade tailing edge 312 and the fan blade leading edge 314 is between about 1½ inches and 10 inches. The fan blade assembly 300 may be selected to be an automotive radiator cooling fan.
While specific embodiments of the invention have been described and illustrated, such embodiments should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims.
