U.S. patent application number 11/865213 was filed with the patent office on 2008-04-17 for box fan grill with integral motor support.
This patent application is currently assigned to Lasko Holdings, Inc.. Invention is credited to Charles D. Litvin.
Application Number | 20080089798 11/865213 |
Document ID | / |
Family ID | 39303262 |
Filed Date | 2008-04-17 |
United States Patent
Application |
20080089798 |
Kind Code |
A1 |
Litvin; Charles D. |
April 17, 2008 |
BOX FAN GRILL WITH INTEGRAL MOTOR SUPPORT
Abstract
A box fan with a motor and impeller that is supported by a
polymer grill is provided. The device may include a metal body and
at least one polymer grill, a motor and an axial air impeller. The
motor being structurally supported by the polymer grill.
Inventors: |
Litvin; Charles D.; (West
Chester, PA) |
Correspondence
Address: |
WOODCOCK WASHBURN LLP
CIRA CENTRE, 12TH FLOOR, 2929 ARCH STREET
PHILADELPHIA
PA
19104-2891
US
|
Assignee: |
Lasko Holdings, Inc.
Wilmington
DE
|
Family ID: |
39303262 |
Appl. No.: |
11/865213 |
Filed: |
October 1, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60829766 |
Oct 17, 2006 |
|
|
|
Current U.S.
Class: |
417/423.15 |
Current CPC
Class: |
F04D 29/023 20130101;
F05D 2230/53 20130101; F05D 2300/43 20130101; F24F 7/007 20130101;
F04D 25/0613 20130101; F04D 29/703 20130101 |
Class at
Publication: |
417/423.15 |
International
Class: |
F04D 29/60 20060101
F04D029/60; F04B 17/03 20060101 F04B017/03; F24F 7/007 20060101
F24F007/007; F04D 25/06 20060101 F04D025/06 |
Claims
1. A box fan comprising: a fan body formed of metal comprising: at
least one wall forming a substantially polygonal shape having a
rear body opening and a front body opening substantially parallel
to said rear body opening and located on the opposite side of said
fan body from said rear body opening; a unitary rear grill formed
of polymer disposed proximate and substantially covering said rear
body opening, said unitary rear grill comprising; a perimeter rail
defining extents of said unitary rear grill; a plurality of grill
elements defining flow through openings, said flow through openings
allowing air to pass through said unitary rear grill; an integrated
motor interface structure substantially centered with reference to
said extents of said unitary rear grill; a front grill disposed
proximate and substantially covering said front body opening; an
interior space defined by said at least one wall of said fan body,
said unitary rear grill, and said front grill; a motor having a
shaft extension disposed within said interior space, said motor
being connected to and structurally supported by said integrated
motor interface structure of said unitary rear grill; and an axial
air impeller disposed within said interior space, said air impeller
comprising; a hub connected to said shaft extension of said motor;
a plurality of blades extending radially outward from said hub.
2. The box fan of claim 1, wherein said unitary rear grill further
comprises support channels extending from said motor interface
structure to said perimeter rail of said unitary rear grill, said
support channels structurally support said motor and said axial air
impeller.
3. The box fan of claim 2, wherein said support channel further
defines a conduit and electric conducting wires of said box fan are
located in said conduit.
4. The box fan of claim 2, wherein perimeter rail, grill elements,
motor interface, and support channels are a single molded polymer
part.
5. The box fan of claim 4, wherein said single molded polymer part
electrically isolates said motor from all external surfaces of said
box fan.
6. The box fan of claim 2, wherein said support channel further
comprises at least one wall defining a recess.
7. The box fan of claim 1, wherein at least a portion of said
plurality of grill elements extend from said motor interface
structure to said perimeter rail of said unitary rear grill and
said portion of said plurality of grill elements structurally
support said motor and said axial air impeller.
8. The box fan of claim 1, wherein said unitary rear grill
comprises a spherical form as defined by a surface of the rear
grill, wherein said surface comprises a spherical radius.
9. The box fan of claim 1, wherein said motor further comprises a
rear end bell including ventilation openings and said integrated
motor interface further comprises: a motor mounting surface; and a
cooling opening substantially centered in said motor mounting
surface; wherein said ventilation openings of said rear end bell
and said cooling opening in said integrated motor interface are
substantially aligned.
10. The box fan of claim 9, wherein said hub of said axial air
impeller further comprises a first circumferential periphery and
said motor mounting surface is defined by a second circumferential
periphery and said first and said second circumferential
peripheries are substantially aligned.
11. The box fan of claim 1, wherein said integrated motor interface
structure further comprises a plurality of motor mounting
holes.
12. The box fan of claim 1, wherein said unitary rear grill further
comprises a unitary handle.
13. The box fan of claim 1, further comprising a controller wherein
said motor and controller is accessible through said unitary rear
grill.
14. The box fan of claim 13, wherein said unitary rear grill
further comprises a handle as an integral part of said unitary rear
grill.
15. The box fan of claim 1, wherein said perimeter rail further
comprises: a first wall substantially parallel to said grill
elements; a second wall extend substantially orthogonal and outward
from said first wall; and a third wall extending substantially
orthogonal from said second wall.
16. The box fan of claim 1, wherein said rear grill perimeter rail
further comprises: a first wall substantially parallel to said
grill elements; a second wall extending outward from said first
wall; a recess formed in said second wall; a third wall extending
from said second wall, said third wall oriented substantially
orthogonal to said first wall; and angular ribs extending between
said first wall and said third wall, said angular ribs connecting
said first wall, said second wall, and said third wall.
17. The box fan of claim 1, wherein said rear grill further
comprises: horizontal structural supports extending from said
integrated motor interface to sides of said perimeter rail; and
vertical structural supports extending from said integrated motor
interface to a top and a bottom of said perimeter rail.
18. The box fan of claim 17, wherein said horizontal structural
supports and said vertical structural supports are constructed
dimensionally thicker than said grill elements.
19. The box fan of claim 1, wherein said rear grill further
comprises: a plurality of substantially concentric arcuate grill
elements; and radial structural supports extending radially from
said integrated motor interface to said perimeter rail, said radial
structural supports connected to said concentric arcuate grill
elements.
20. A box fan comprising: a fan body formed of metal comprising: at
least one wall forming a substantially polygonal shape having a
rear body opening and a front body opening substantially parallel
to said rear body opening and located on the opposite side of said
fan body from said rear body opening; a unitary rear grill formed
of polymer disposed proximate and substantially covering said rear
body opening, said unitary rear grill comprising; a perimeter rail
defining extents of said unitary rear grill; a plurality of grill
elements defining flow through openings, said flow through openings
allowing air to pass through said unitary rear grill; a
substantially circular-shaped integrated motor interface structure
substantially centered with reference to said extents of said
unitary rear grill; support channels extending between and
connecting said motor interface structure to said perimeter rail of
said unitary rear grill; a front grill disposed proximate and
substantially covering said front body opening; an interior space
defined by said at least one wall of said fan body, said unitary
rear grill, and said front grill; a motor disposed within said
interior space, said motor being connected to and structurally
supported by said integrated motor interface structure of said
unitary rear grill, said motor having a shaft extension; an axial
air impeller disposed within said interior space, said air impeller
comprising; a hub connected to said shaft extension of said motor;
a plurality of blades extending radially outward from said hub.
21. A box fan comprising: at least one wall formed of metal forming
a substantially polygonal shape; a rear opening formed by said at
least one wall; a front opening formed by said at least one wall,
said front opening oriented substantially parallel to said rear
body opening and located on the opposite side of said at least one
wall; a front grill disposed proximate and substantially covering
said front opening; a plurality of front grill elements defining
front flow through openings, said front flow through openings
allowing air to pass through said front grill a rear grill disposed
proximate and substantially covering said rear opening; a perimeter
rail defining extents of said rear grill; a plurality of rear grill
elements defining rear flow through openings, said rear flow
through openings allowing air to pass through said rear grill; a
substantially circular shaped integrated motor interface structure
substantially centered with reference to said extents of said rear
grill; motor cooling openings in a center region of said integrated
motor interface structure; support channels extending outward from
said motor interface structure and connect to said perimeter rail;
wherein said rear grill, said perimeter rail, said rear grill
elements, said motor interface, and said support channels are a
single molded polymer part; an interior space defined by said at
least one wall of said fan body, said front grill, and said rear
grill; a motor disposed within said interior space, said motor
being connected to and structurally supported by said integrated
motor interface structure of said rear grill; a shaft extending
from said motor; a rear end bell of said motor; ventilation
openings in said rear end bell, wherein said ventilation openings
of said motor rear end bell substantially align with said motor
cooling openings in said integrated motor interface structure; an
axial air impeller disposed within said interior space; a
substantially circular shaped hub of said air impeller connected to
said motor shaft, wherein a circumference of said substantially
circular shaped hub is substantially equal to said substantially
circular shaped integrated motor interface structure; and a
plurality of blades of said air impeller extending radially outward
from said hub.
Description
CROSS-REFERENCE APPLICATIONS
[0001] This application claims priority to provisional patent
application 60/829,766 filed Oct. 17, 2006.
TECHNOLOGY FIELD
[0002] The present invention relates to an air moving apparatus.
More specifically, the present invention relates to the motor
mounting structure utilized on a conventional box fan.
BACKGROUND
[0003] The box fan has been in existence for many years. The box
fan has proven itself to be one of the most versatile air moving
devices, selling numerous millions of units every year. Because of
its popularity there has been constant pressure on the manufacturer
to produce the box fan less expensively without compromising the
safety or the quality of the final product.
[0004] One manner to effectively achieve this goal is to reduce the
material usage and by default the raw material cost needed to
produce the device. The use of motor production technology, plastic
materials, size reduction etc. have all yielded cost reductions for
the box fan over the years.
[0005] What is needed are further innovations in the box fan
structure that will maintain or improve the quality and safety of
the device while at the same time allow the manufacturer the
ability to produce the device at a lower cost. The lower cost will
enhance the appeal of the item to a greater number of users.
SUMMARY
[0006] The present invention is directed to embodiments of a box
fan that utilizes a motor mounting structure incorporated into a
polymer rear grill of the device. The utilization of the polymer
grill in this manner eliminates the need for metal brackets and the
additional labor needed to assemble the metal brackets in the
construction of a conventional box fan. This reduces the cost of
the box fan to the consumer and allows the product to be more
affordable to a wider range of users and more profitable to the
manufacturer. Another advantage of the described device is the
ability of the polymer rear grill to electrically isolate the motor
of the device from external metal components such as the body of
the box fan.
[0007] In accordance with one embodiment, a box fan includes a fan
body formed of metal comprising at least one wall forming a
substantially polygonal shape having a rear body opening and a
front body opening. The front and rear openings are substantially
parallel to one another and are located on the opposite side of the
fan body. A unitary rear grill formed of polymer may be disposed
proximate and substantially covering the rear body opening. The
unitary rear grill includes a perimeter rail defining extents of
the unitary rear grill, a plurality of grill elements defining flow
through openings that allow air to pass through the unitary rear
grill, and an integrated motor interface structure substantially
centered with reference to the extents of the unitary rear grill.
The box fan includes a front grill disposed proximate and
substantially covering the front body opening. An interior space is
defined by the at least one wall of the fan body, the unitary rear
grill, and the front grill. A motor having a shaft extension is
disposed within the interior space. The motor is connected to and
structurally supported by the integrated motor interface structure
of the unitary rear grill. An axial air impeller is disposed within
the interior space. The air impeller includes a hub connected to
the shaft extension of the motor, and a plurality of blades
extending radially outward from the hub.
[0008] According to one aspect of the invention, the unitary rear
grill includes support channels extending from the motor interface
structure to the perimeter rail of the unitary rear grill. The
support channels structurally support the motor and the axial air
impeller. The support channel may define a conduit and control
wires of the box fan may be located in the conduit. The support
channel may include at least one wall defining a recess.
[0009] According to another aspect of the invention, the at least a
portion of the plurality of grill elements extend from the motor
interface structure to the perimeter rail of the unitary rear
grill. This portion of the plurality of grill elements functions,
in part, to structurally support the motor and the axial air
impeller.
[0010] According to another aspect of the invention, the unitary
rear grill comprises a spherical form as defined by a surface of
the rear grill, wherein the surface comprises a spherical
radius.
[0011] According to another aspect of the invention, the motor
includes a rear end bell having ventilation openings. The
integrated motor interface includes a motor mounting surface, and a
cooling opening substantially centered in the motor mounting
surface. The ventilation openings of the rear end bell and the
cooling opening in the integrated motor interface may be
substantially aligned.
[0012] According to another aspect of the invention, the hub of the
axial air impeller further comprises a first circumferential
periphery and the motor mounting surface is defined by a second
circumferential periphery. The first and the second circumferential
peripheries may be substantially aligned.
[0013] According to another aspect of the invention, the integrated
motor interface structure further comprises a plurality of motor
mounting holes for receiving fasteners to secure the motor to the
integrated motor interface structure.
[0014] According to another aspect of the invention, the perimeter
rail, grill elements, motor interface, and support channels are a
single molded polymer part. The single molded polymer part
electrically isolates the motor from all external surfaces of the
box fan.
[0015] According to another aspect of the invention, the perimeter
rail includes: a first wall substantially parallel to the grill
elements; a second wall extend substantially orthogonal and outward
from the first wall; and a third wall extending substantially
orthogonal from the second wall.
[0016] According to another aspect of the invention, the rear grill
perimeter rail includes: a first wall substantially parallel to the
grill elements; a second wall extending outward from the first
wall; a recess formed in the second wall; a third wall extending
from the second wall, the third wall oriented substantially
orthogonal to the first wall; and angular ribs extending between
the first wall and the third wall, the angular ribs connecting the
first wall, the second wall, and the third wall.
[0017] According to yet another aspect of the invention, the rear
grill further includes: horizontal structural supports extending
from the integrated motor interface to sides of the perimeter rail;
and vertical structural supports extending from the integrated
motor interface to a top and a bottom of the perimeter rail. The
horizontal structural supports and the vertical structural supports
may be constructed dimensionally thicker than the grill
elements.
[0018] According to another aspect of the invention, the rear grill
includes: a plurality of substantially concentric arcuate grill
elements; and radial structural supports extending radially from
the integrated motor interface to the perimeter rail. The radial
structural supports may be connected to the concentric arcuate
grill elements.
[0019] According to another embodiment of the invention, a box fan
includes a fan body formed of metal. The fan body includes at least
one wall forming a substantially polygonal shape having a rear body
opening and a front body opening. The rear and front openings are
substantially parallel to one another and located on the opposite
sides of the fan body. A unitary rear grill may be formed of
polymer and may be disposed proximate and substantially covering
the rear body opening. The unitary rear grill includes a perimeter
rail defining extents of the unitary rear grill. The unitary rear
grill also includes a plurality of grill elements defining flow
through openings, the flow through openings allowing air to pass
through the unitary rear grill. The unitary rear grill further
includes a substantially circular-shaped integrated motor interface
structure substantially centered with reference to the extents of
the unitary rear grill. Moreover, the unitary rear grill includes
support channels extending between and connecting the motor
interface structure to the perimeter rail of the unitary rear
grill. The box fan also includes a front grill disposed proximate
and substantially covering the front body opening. An interior
space is defined by the at least one wall of the fan body, the
unitary rear grill, and the front grill. A motor is disposed within
the interior space, the motor being connected to and structurally
supported by the integrated motor interface structure of the
unitary rear grill. The motor also has a shaft extension. An axial
air impeller is disposed within the interior space. The air
impeller includes a hub connected to the shaft extension of the
motor and a plurality of blades extending radially outward from the
hub.
[0020] According to yet another embodiment of the invention, a box
fan includes at least one wall formed of metal forming a
substantially polygonal shape. Rear and front openings are formed
by the at least one wall. The rear and front openings are oriented
substantially parallel to one another and are located on the
opposite sides of the at least one wall. A front grill is disposed
proximate and substantially covering the front opening. The front
grill includes a plurality of front grill elements defining front
flow through openings that allow air to pass through the front
grill. A rear grill is disposed proximate and substantially
covering the rear opening. A perimeter rail defines extents of the
rear grill. The rear grill includes a plurality of rear grill
elements defining rear flow through openings that allow air to pass
through the rear grill. The rear grill also includes a
substantially circular shaped integrated motor interface structure
substantially centered with reference to the extents of the rear
grill. Motor cooling openings may be provided in a center region of
the integrated motor interface structure. Support channels may
extend outward from the motor interface structure and connect to
the perimeter rail. The rear grill, the perimeter rail, the rear
grill elements, the motor interface, and the support channels are
preferably formed as a single molded polymer part. An interior
space is defined by the at least one wall of the fan body, the
front grill, and the rear grill. A motor is disposed within the
interior space and may be connected to and structurally supported
by the integrated motor interface structure of the rear grill. The
motor includes a shaft and a rear end bell. Ventilation openings
may be provided in the rear end bell. Preferably, the ventilation
openings of the motor rear end bell substantially align with the
motor cooling openings in the integrated motor interface structure.
An axial air impeller is disposed within the interior space. A
substantially circular shaped hub of the air impeller connects to
the motor shaft. A circumference of the substantially circular
shaped hub may be substantially equal to the substantially circular
shaped integrated motor interface structure. A plurality of blades
of the air impeller extend radially outward from the hub.
[0021] The use of the polymer rear grill to support the motor can
incorporate other features within the structure such as, for
example: handles, switches, improved cooling features, etc. These
features combined with the incorporation of the motor support into
the rear polymer grill of the box fan yield further cost savings
for the user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] 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:
[0023] FIG. 1 is a rear perspective view of an exemplary box fan in
accordance with embodiments of the present invention;
[0024] FIG. 2 is a front perspective exploded view of the exemplary
box fan of FIG. 1;
[0025] FIG. 3A is a rear perspective view illustrating an
embodiment of a grill of the present invention;
[0026] FIG. 3B is a partial cross section through a support channel
of the grill embodiment of FIG. 3A;
[0027] FIG. 3C is a partial cross section view through the a
perimeter rail of the grill embodiment of FIG. 3A;
[0028] FIGS. 3D and 3E are a partial cross sectional view and a
partial front view respectively of an alternate embodiment for the
perimeter rail;
[0029] FIG. 4 is a rear perspective view illustrating an
alternative structure for an embodiment of a grill of the present
invention;
[0030] FIG. 5 is a rear perspective view illustrating another
alternative structure for an embodiment of a grill of the present
invention;
[0031] FIGS. 6A, 6B and 6C are rear, top and side views of another
embodiment of the present invention; and
[0032] FIG. 7 shows another embodiment of the present invention in
conjunction with various incorporated features.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0033] 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.
[0034] 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.
[0035] 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.
[0036] 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.
[0037] 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.
[0038] 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.
[0039] 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.
[0040] 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.
[0041] 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.
[0042] 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.
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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.
[0047] 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.
[0048] 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.
[0049] 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.
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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.
[0055] 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.
[0056] 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.
[0057] 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.
[0058] 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.
[0059] 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.
[0060] 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.
[0061] 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.
[0062] 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.
[0063] 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.
[0064] 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.
[0065] 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.
[0066] 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.
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