BRIEF DESCRIPTION OF THE DRAWINGS
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawings are the following Figures:
FIG. 1 is a rear perspective view of an exemplary box fan in accordance with embodiments of the present invention;
FIG. 2 is a front perspective exploded view of the exemplary box fan of FIG. 1;
FIG. 3A is a rear perspective view illustrating an embodiment of a grill of the present invention;
FIG. 3B is a partial cross section through a support channel of the grill embodiment of FIG. 3A;
FIG. 3C is a partial cross section view through the a perimeter rail of the grill embodiment of FIG. 3A;
FIGS. 3D and 3E are a partial cross sectional view and a partial front view respectively of an alternate embodiment for the perimeter rail;
FIG. 4 is a rear perspective view illustrating an alternative structure for an embodiment of a grill of the present invention;
FIG. 5 is a rear perspective view illustrating another alternative structure for an embodiment of a grill of the present invention;
FIGS. 6A, 6B and 6C are rear, top and side views of another embodiment of the present invention; and
FIG. 7 shows another embodiment of the present invention in conjunction with various incorporated features.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
FIG. 1 is a rear perspective view of box fan 100. As shown, box fan 100 includes rear grill 110, front grill 150 and body 120. Body 120 may be fabricated of metal and is generally polygonal in shape. In a preferred embodiment, body 120 includes four surfaces 120a arranged in two substantially parallel sets, the first substantially parallel set is positioned substantially orthogonal to the second substantially parallel set. For example, the first substantially parallel set may be positioned horizontally and the second substantially parallel set may be positioned vertically. In a preferred embodiment, corners 120b where orthogonal surfaces 120a meet are arcuate in form. It is contemplated that other shapes and/or non-arcuate corners can be utilized as alternative embodiments of corners 120b.
Rear grill 110 is fabricated of polymer and is substantially planar in form. As shown in this example, the substantially planar form of rear grill 110 is positioned substantially orthogonal to all surfaces 120a of body 120. Also as shown, front grill 150 is substantially planar in form and is positioned substantially parallel to rear grill 110 on the opposing side of body 120.
As shown, body 120, rear grill 110 and front grill 150 define interior space 123. Disposed within interior space 123 is electric motor 130 and axial air impeller 140. Electric motor 130 rotates axial air impeller 140 causing air to enter interior space 123 through either rear grill 110 or front grill 150. The air is accelerated and exits interior space 123 as an exhaust air flow through either rear grill 110 or front grill 150.
Also shown in FIG. 1 is handle 160 and control 162. Handle 160 is used to facilitate the portability of box fan 100. Control 162 controls a function of box fan 100, such as, for example, the rotational speed of electric motor 130 and axial air impeller 140.
Power cord 105 may be utilized to connect box fan 100 to an electrical power source (i.e. wall outlet). The electrical component connections of box fan 100 are integrated within the device, such as, for example, between control 162 and motor 130. The integration of the electrical component connections within the device eliminates the need for the user to make such connections. In the exemplary embodiment shown, only the connection of power cord 105 to an electrical power source is required for operation of box fan 100.
Preferably, power cord 105 utilizes a safety plug. Details of the safety plug and its advantages can be referenced in U.S. Pat. No. 6,793,535, which is hereby incorporated into this patent application in its entirety.
FIG. 2 is a front perspective exploded view of box fan 100 of FIG. 1. As shown, body 120 includes front perimeter lip 128a and rear perimeter lip 128b. Front body opening 124 as shown, is defined by front perimeter lip 128a. Rear body opening 122 may similarly be defined by rear perimeter lip 128b. Located on both front and rear perimeter lips 128a and 128b are holes 126. Holes 126 are used to attach front and rear grills, 150 and 110 respectively, to body 120. It is contemplated that assembly devices (not shown) such as, for example, screws may be utilized via holes 126 in body 120 and holes 153, 113 of front and rear grills, 150 and 110 respectively, to assemble front and rear grills 150 and 110 to body 120. It is further contemplated that other assembly devices such as adhesives or snaps may be used to assemble front grill 150 and rear grill 110 to body 120. Interior space 123 of box fan 100 is defined by the assembly of body 120, front grill 150 and rear grill 110.
Front grill 150 may include, as shown, perimeter rail 152. Perimeter rail 152 defines the planar extents of front grill 150. Vertical and horizontal grill elements 156 are located within the planar area defined by perimeter rail 152. Grill elements 156 are designed to minimize their impedance to the flow of air into and/or exiting box fan 100 while at the same time protecting box fan 100 from the penetration of foreign objects into interior space 123.
As shown, rear grill 110 may include perimeter rail 112. Perimeter rail 112 defines the planar extents of rear grill 110. Vertical and horizontal grill elements 116 are located within the planar area defined by perimeter rail 112. Grill elements 116 are designed to minimize their impedance to the flow of air into and/or exiting box fan 100 while at the same time protecting box fan 100 from the penetration of foreign objects into interior space 123. Rear grill 110 also includes motor interface 118 and support channels 114. As shown, support channels 114 extend from motor interface 118 outward to perimeter rail 112. In a preferred embodiment, perimeter rail 112, grill elements 116, motor interface 118 and support channels 114 are a single molded polymer part.
As shown, electric motor 130 and axial air impeller 140 are disposed within interior space 123. Electric motor 130 is attached to motor interface 118 of rear grill 110 via motor mounting holes 111. It is contemplated that assembly devices, (not shown) such as, for example; screws can be utilized via motor mounting holes 111 to assemble electric motor 130 to rear grill 110. It is further contemplated that other assembly devices such as adhesives or snaps may be used to assemble electric motor 130 to rear grill 110.
Electric motor 130 may include at least one shaft 132, rear end bell 134, front end bell 136 and ventilation openings 138 in both rear end bell 134 and front end bell 136. Axial air impeller 140 is attached to shaft 132 and rotated by electric motor 130.
Axial impeller 140 may include hub 142 and multiple blades 144. As shown, hub 144 has a circular form. The rotation of axial air impeller 140 generates and exhaust air flow, as described with reference to FIG. 1.
It can be appreciated that assembling electric motor 130 to rear grill 110 has an advantage of electrically isolating electric motor 130 from all external surfaces of box fan 100. This advantage serves to provide greater safety for the user when compared to conventional box fans that utilize metal mounting brackets. It can also be seen that assembling electric motor 130 to rear grill 110 has a manufacturing advantage of eliminating the metal motor mounting brackets commonly used on a conventional box fan. The elimination of the metal brackets not only eliminates the material required to fabricate the metal brackets, but also eliminated the assembly process and labor associated with attaching the metal brackets to body 120. The material and assembly cost reductions combined with the additional safety of box fan 100 enhance marketability when compared to a conventional box fan.
Also shown in FIG. 2 are handle 160 and control 162. As shown, handle 160 is attached to body 120 through holes 125 located in body 120. It contemplated that assembly devices such as adhesives, snaps or screws may be used in conjunction with holes 125 to attach handle 160 to body 120. Control 162 may include such items, (not shown) such as switches, knobs, thermostats, LEDs and power control boards. It is also contemplated that a remote control may be used in lieu of and/or in conjunction with control 162. Control 162 may be external to body 120 and/or partially located within interior space 123 of body 120. As shown, passage 127 permits control 162 to access both internal space 123 and exterior of body 120.
FIG. 3A is a rear perspective view of rear grill 110. As shown, in a preferred embodiment perimeter rail 112 includes at least six holes 113 used to assemble rear grill 110 to body 120 of box fan 100. It is contemplated that more and/or fewer holes 113 can be used to assemble rear grill 110 to body 120.
As shown, support channels 114a, 114b, 114c and 114d extend outward from motor interface 118 and connect to perimeter rail 112. It is contemplated that multiple support channels 114 may extend from motor interface 118 and connect at a plurality of locations along perimeter rail 112. In a non-limiting fashion four support channels 114 are shown.
In a preferred embodiment, motor interface 118 is substantially circular in shape as defined by circumference 118a. In one exemplary embodiment, circumference 118a of motor interface 118 is approximately the same size as hub 142 of impeller 140, see FIG. 2. Located proximate the center of motor interface 118 are motor cooling openings 118b. In one exemplary embodiment, openings 118b are substantially aligned with ventilation openings 138 of rear end bell 134 of motor 130, see FIG. 2. Openings 118b may include grill elements 118c. The shape and size of circumference 118a, motor cooling openings 118b and grill elements 118c are utilized to allow motor interface 118 to function as an air impedance shield as per U.S. patent application Ser. No. 10/903,061, filed Jul. 30, 2004, which is hereby incorporated by reference into this patent application in its entirety.
Also shown is a plurality of motor mounting holes 111. In a preferred embodiment, the number of motor mounting holes 111 is about four; however, the invention is not so limited. It is contemplated that any number of motor mounting holes 111 may be used.
Vertical and horizontal grill elements 116 define flow through openings 117. Although grill elements 116 are shown horizontal and vertically orthogonal to one another the invention is not so limited. It is contemplated that other shaped such as arcuate shaped and radially oriented grill elements may be used.
FIG. 3B is a partial cross section view cut through support channel 114 of the rear grill 110 of FIG. 3A. As shown, support channel 114 includes recess 306 and walls 115a and 115b. The use of walls 115a and 115b increase the structural integrity of support channel 114 and enhance the ability of rear grill 110 to support the weight and dynamic forces of motor 130 and axial air impeller 140. Support channel 114 may also be used as a conduit for wires 304. Wires 304 electrically connect components of box fan 100 such as, for example, control 160, motor 130 and power cord 105. Clips 302, used to retain wires 304 within space 308 of support channel 114 can be molded integral to support channel 114 or be a separate component. Although support channel 114 is shown having a substantially rectangular cross sectional form the invention is not so limited, it is contemplated that the cross sectional form of support channel 114 may include triangular and arcuate forms as well.
FIG. 3C is a partial cross section view cut through perimeter rail 112 of rear grill 110 of FIG. 3A. Perimeter rail 112 as shown supports the vertical and horizontal grill elements 116 of rear grill 110. The cross sectional form of perimeter rail 112 includes walls 112a, 112b and 112c. The substantially orthogonal and parallel relationships of walls 112a, 112b and 112c increase the structural integrity of perimeter rail 112.
FIGS. 3D and 3E show a partial cross sectional side view and a partial front view respectively of an alternate embodiment for the perimeter rail. As shown, perimeter rail 312 includes recess 315, walls 316a, 316b, 316c and angular ribs 318. As shown in FIG. 3E, angular ribs 318 are oriented at an angle relative to walls 316a, 316b and 316c and serve to connect walls 316a, 316b and 316c together. The use of walls 316a, 316b and 316c in conjunction with ribs 318 increase the structural integrity of perimeter rail 312 and enhance the ability of rear grill 110 to support motor 130 and axial air impeller 140 via support channels 114.
FIG. 4 is a rear perspective view of rear grill 410. Rear grill 410 is an alternative embodiment for rear grill 110 of FIG. 3A. As shown, rear grill 410 uses horizontal structural supports 402 and vertical structural supports 404 to enhance the structural integrity of motor interface 118. Horizontal structural supports 402 and vertical structural supports 404 are used in lieu of support channels 114, as shown on rear grill 110 of FIG. 3A. Horizontal structural supports 402 and vertical structural supports 404 may be constructed dimensionally thicker than grill elements 116 while not overtly departing from the homogeneous appearance of grill elements 116. In other respects, rear grill 410 may be similar to the embodiment of rear grill 110 of FIG. 3A.
FIG. 5 is a rear perspective view of rear grill 510. Rear grill 510 is an alternative embodiment for rear grill 110 of FIG. 3A. As shown, rear grill 510 uses radial structural supports 502 to enhance the structural support of motor interface 118. Another aspect of rear grill 510 that contributes to the structural support of motor interface 118 are the substantially concentric arcuate grill elements 516. Radial structural supports 502 and substantially concentric arcuate grill elements 516 are used in lieu of support channels 114, as shown on rear grill 110 of FIG. 3A. Radial structural supports 502 may be constructed dimensionally thicker than grill elements 516 thus enhancing their structure without departing from the homogeneous overall appearance of rear grill 510. In other respects, rear grill 510 may be similar to the embodiment of rear grill 110 of FIG. 3A.
FIGS. 6A, 6B and 6C are rear, top and side views of box fan 600. Box fan 600 utilizes rear grill 610. Rear grill 610 has a spherical form as defined by spherical radius R in both top view FIG. 6B and side view FIG. 6C. Spherical radius R of rear grill 610 increases the overall rigidity of the structure supporting motor interface 118. As shown, radius R is convex relative to body 120, however the invention is not so limited. It is contemplated that spherical radius R may be concave relative to body 120.
In the illustrated embodiment of rear grill 610, support channels 114 are used. It is contemplated that other support structures such as, for example, horizontal structural supports 402 and vertical structural supports 404 of FIG. 4 and/or radial structural supports 502 and substantially concentric arcuate grill elements 516 of FIG. 5 may be used in conjunction with spherical radius R. In other respects, box fan 600 may be similar to box fan 100 of FIG. 1.
FIG. 7 shows in a non-limiting fashion other features that can be incorporated into box fan 700. As shown, FIG. 7 handle 760 is an integral part of rear grill 710. This has the advantage of not requiring the additional component and assembly of handle 160 as shown in FIG. 1.
Also shown in FIG. 7 is control 762. Control 762 is located near motor 130 and is allowed access to motor 130 through rear grill 710. This feature has the advantage of eliminating the a control wire (not shown) required to connect motor 130 to control 162 located at a more remotely as shown in FIG. 1. This feature also allows control 762 and motor 130 to be pre assembled as a sub assembly bringing further advantages to the assembly process.
In the illustrated embodiment of rear grill 710, support channels 114 are used. It is contemplated that other support structures such as, for example, horizontal structural supports 402 and vertical structural supports 404 of FIG. 4 and/or radial structural supports 502 and substantially concentric arcuate grill elements 516 of FIG. 5 may be used in conjunction with handle 760 and control 762. In other respects, box fan 700 may be similar to box fan 100 of FIG. 1.
As described and shown, box fan 100 utilizing motor interface 118 incorporated into polymer rear grill 110 eliminates the need for metal motor mounting brackets and the additional labor to assemble the metal brackets used on a conventional box fan. This reduces the final cost of the box fan. Another advantage of incorporating motor interface 118 into rear grill 110 is the ability of the polymer material of rear grill 110 to electrically isolate motor 130 from external metal components of box fan 100 such as, for example, the body 120.
As described and shown, body 120 of box fan 100 is substantially the same as the body used on a conventional box fan. The similarities between body 120 of box fan 100 and the body used on a conventional box fan allow the manufacturer to easily alternate between the production of box fan 100 with motor interface 118 and the production of a conventional box fan with metal brackets. The ability to alternate production allows the manufacturers to respond to material costs and produce the box fan that yields the most cost savings.
As described and shown, the use of the polymer rear grill to support the motor can also incorporate other features within the structure such as, for example; handles, switches, improved cooling features, etc. The combination of these features and the motor support incorporated into the rear polymer grill of the box fan yield further cost savings for the user.
The box fan structure as described will maintain or improve the quality and safety of the device while permitting the manufacturer the flexibility of production to produce the device at a lower cost.
Although the invention has been described with reference to exemplary embodiments, it is not limited thereto. Rather, the appended claims should be construed to include other variants and embodiments of the invention, which may be made by those skilled in the art without departing from the true spirit and scope of the present invention.