Window Fan

Abstract

A window fan is provided that includes a fan housing and chamber assembly. The fan housing includes a front panel with an air outlet and a rear panel with an air inlet and defines a central chamber. The chamber assembly is positioned within the central chamber of the fan housing and includes a cylindrical fan rotatably mounted within the chamber and driven by a fan motor. An air duct assembly is rotatably mounted within the chamber having an air duct panel that is moveable from an open to closed position such that the air duct panel, when in the closed position blocks the airflow through the window fan and permits air flow through the window fan when in the open position. The fan of the window fan assembly may be a cross flow blower fan.

Description

FIELD OF INVENTION

The invention relates to a window fan, and in particular a window fan having a cross flow blower configuration and a removable panel for opening and closing air flow through the air duct of the window fan.

BACKGROUND

Window fans are a low cost alternative to air conditioning units to help provide a more comfortable temperature within an interior space, and to provide additional ventilation. Like window air conditioning units, window fans are installed within the frame of a window and may be used to exhaust an from the interior space outside or direct outside air into the interior space.

A window fan typically contains a housing unit with a front and rear panel, a fan and a motor for rotating the fan. The front and rear panels both contain openings (e.g., grills) so that when turned on, the window fan both draw in air from the outside into the interior space (e.g., fan mode) or draws air from inside of the space to the outside (e.g., exhaust mode).

Many window fans include two or more reversable axial fans positioned side by side, or in series, e.g., dual 8″ or 9″ fans, of various speeds that often give the appearance of side-by-side box fans for positioning in a window. Such axial fan designs positioned in series create a relatively tall and bulky window fan design. Further, because the exterior side of the window fan is exposed to the outside environment, the interior of the fan's housing is exposed to and can accumulate environmental elements such as dust, rain, ice, dirt, insects, spider webs, leaves, etc. which can decrease the performance of the window fan. Such outside elements, such as insects, spiders, airborne particles and debris, are also likely to enter the interior space though the grills when the fan is not in use. To address these concerns, window fans are usually required to be removed from the window and stored when not in use so that the window can be closed. When the user then desires to use the window fan again, it must be reinstalled prior to use.

As such, there is a need for an improved window fan that provides a lower profile, sleeker, more attractive design that is not only able to block the entry of insects, spiders, airborne particles and debris from the outside into the interior space, but also allow user to keep the window fan in the window when not in use.

SUMMARY

A window fan is provided that includes a fan housing and chamber assembly. The fan housing includes a front panel with an air outlet and a rear panel with an air inlet and defines a central chamber. The chamber assembly is positioned within the chamber of the fan housing and includes a cylindrical fan rotatably mounted within the chamber and driven by a first motor or fan motor and an air duct assembly rotatably mounted within the chamber having an air duct panel that is moveable from an open to closed position such that the air duct panel, when in the closed position blocks the airflow through the window fan and permits air flow through the window fan when in the open position. The fan of the window fan assembly may be a cross flow blower. By using a cross flow blower, the window fan construction is considerably shorter and sleeker than traditional window fans using axial fans positioned in series.

The window fan includes a fan housing having a front cover, rear cover, top panel, bottom cover and left and right end caps. The front cover includes an air outlet (or fan grill) and the rear and/or bottom cover includes an air inlet or exhaust grill. Further, a sill insert is provided along the bottom cover for stabilizing the window fan in the casing of a window.

Positioned within the window fan is a chamber assembly that includes a fan, air duct assembly and a motor assembly. The motor assembly includes a motor housing which contains a first or main motor, a gear assembly, and a secondary motor. A controller or PCB board 300 is also included that is in communication with the motor assembly to control the operation of the fan and air duct assembly.

In one example, the window fan includes a fan housing having a front panel with an air outlet and a rear panel with an air inlet. The fan housing further defines a central chamber having a chamber assembly positioned therein. The chamber assembly includes a fan rotatably mounted within the chamber, which may be a cross flow blower, driven by a fan motor (which may be a reversible motor). The chamber assembly further includes an air duct assembly rotatably mounted within the chamber having an air duct panel moveable from an open to closed position. When in the closed position, the air duct panel blocks the airflow through the window fan. The window fan may further include a second motor for moving the air duct panel from an open to closed position. The second motor may also be a reversible motor. The second motor may also be offset from the fan motor and be in communication with a gear assembly affixed to the air duct assembly for rotating the air duct panel.

The window fan housing may further include first and second end caps and at least one modular block for positioning on at least one side of at least one of the first or second end caps. The window fan may further include a sill insert positioned on the bottom of the fan housing. The at least one modular block for positioning on the side of at least one of the first or second end caps may further include a block sill insert for aligning with the sill insert positioned on the bottom of the fan housing. The at least one modular block for positioning on the side of at least one of the first or second end caps may further include a plurality of modular blocks. Further, the plurality of modular blocks may include pairs of modular blocks of various lengths.

In yet another example, the window fan may include a fan housing having an air outlet and an air inlet and a cross flow blower fan mounted within the fan housing and driven by a fan motor. An air duct panel may further be rotatably mounted around the cross flow blower driven by a second or panel motor, where the panel motor is configured to rotate the air duct panel independent of the cross flow blower fan from an open to closed position, where the motor rotates the air duct panel to block the airflow through the window fan when in a closed position. Here, either or both the fan motor and the panel motor may also be reversible. Further, the panel motor may be offset from the fan motor, where the panel motor drives a gear assembly that rotates the air duct panel. The window fan may further include a sill insert positioned on the bottom of the fan housing.

The fan housing may further include first and second end caps and the window fan may include at least one modular block for positioning on the side of at least one of the first or second end caps. The at least one modular block for positioning on the side of at least one of the first or second end caps may include a block sill insert for aligning with the sill insert positioned on the bottom of the fan housing. Again, the at least one modular block for positioning on the side of at least one of the first or second end caps may further include a plurality of modular blocks, which may include pairs of modular blocks of various lengths.

Further, although the figures illustrate the rotation of the air duct assembly using a secondary or panel motor, those skilled in the art will recognize that the air duct assembly may be rotated manually by the use of a level, switch or rotational knob, for example. Other devices, apparatus, systems, methods, features and advantages of the invention are or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.

DESCRIPTION OF THE FIGURES

The invention may be better understood by referring to the following figures. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.

FIG. 1 illustrates a top front perspective view of the window fan of the present invention.

FIG. 2 is a front elevation view of the window fan of FIG. 1.

FIG. 3 is a rear elevation view of the window fan of FIG. 1.

FIG. 4 is a bottom rear perspective view of the window fan of FIG. 1.

FIG. 5 is a front, side perspective view of the window fan of FIG. 1 with the front cover removed.

FIG. 6 is a front, side front perspective view of the window fan of FIG. 1 with the front cover and right end cap removed.

FIG. 7 is a front perspective view of the left side of the fan assembly of the window fan of the present invention

FIG. 8 is a front perspective view of the right side of the fan assembly of the window fan of the present invention.

FIG. 9 is a front perspective view of the right side of the fan assembly with the fan and duct panel removed.

FIG. 10 is a side perspective view of the fan assembly of FIG. 8.

FIG. 11 is a side perspective view of the air duct panel assembly of FIG. 9.

FIG. 12 is a side perspective view of a modular foam block of the present invention.

FIG. 13 is a side perspective view of the right side of the window fan with a modular foam block overlaying the right side of the window fan.

FIG. 14 is a front elevation view of a window fan of the present invention with modular foam blocks positioned on each side of the window fan.

FIG. 15 side rear perspective view of a modular foam block of a first size.

FIG. 16 is a side bottom view of the modular foam block of FIG. 15.

FIG. 17 is a rear view of the modular foam block of FIG. 15.

FIG. 18 side rear perspective view of a modular foam block of a second size.

FIG. 19 is a side bottom view of the modular foam block of FIG. 18.

FIG. 20 is a rear view of the modular foam block of FIG. 18.

FIG. 21 side rear perspective view of a modular foam block of a third size.

FIG. 22 is a side bottom view of the modular foam block of FIG. 21.

FIG. 23 is a rear view of the modular foam block of FIG. 21.

DETAILED DESCRIPTION OF THE INVENTION

As illustrated in the attached FIGS. 1 to 22, a window fan 100 is provided that is considerably shorter and sleeker than prior art window fans, that provides for the air flow through the window fan 100 to be opened or closed and that provides for a modular foam block system to fit the window fan securely into a wide range of window construction styles from various ages.

For purposes of reference and description, the window fan 100 is considered to have a device axis 206 (FIGS. 2 & 3) along which the components of the window fan 100 are positioned relative to each other. Terms such as “axial” and “axially” are assumed to refer to the device axis 206 or any direction or axis parallel to the device axis 206, unless indicated otherwise or the context dictates otherwise. In this disclosure, the plane orthogonal to the device axis 206 is referred to as the transverse plane. For convenience, movement relative to the device axis 206 may alternatively encompass movement relative to an axis that is parallel to the device axis 206 that is specifically illustrated in FIGS. 2 & 3, unless the context dictates otherwise. Thus, linear translation “along the device axis 206” is not limited to translation directly on (coincident with) the device axis 206, but also encompasses translation parallel to the device axis 206, depending on the context. Similarly, rotation “about the device axis 206” also encompasses rotation about an axis that is parallel to the device axis 206, depending on the context.

In one example and as illustrated, the device axis 206 may be oriented generally horizontal to a ground surface or surface on which the window fan 100 is disposed or is intended to be disposed (e.g., window sill). From the perspective of FIG. 2, the ground surface corresponds to a horizontal plane passing orthogonally through the drawing sheet.

FIG. 1 illustrates a top front perspective view of the window fan 100 of the present invention, and FIG. 2 illustrates a front elevation view of the window fan 100 of FIG. 1. As seen in FIG. 1, the window fan 100 includes a fan housing 102 having a front cover 104, which includes an air outlet 106 (or front grill). The fan housing 102 further includes a top panel 108 and opposing first and second, or right and left, end caps 110, 112. A sill insert or channel insert 202 is also provided at the bottom of window fan 100, which may be an elongated foam rubber insert, for aligning the window fan 100 in the exterior channel of the window sill of a window (not shown). A fan 204 can be seen through the air outlet 106, which in this example is a cylindrical fan capable of rotating in at least one direction, such as a cross flow blower fan.

FIG. 3 illustrates a rear elevation view of the window fan 100 of FIG. 1, and FIG. 4 illustrates a bottom rear perspective view of the window fan 100 of FIG. 1. As seen in FIGS. 3 and 4, the window fan 100 includes a rear cover 302 and bottom cover 306 having an air inlet 304 or rear grill that functions to draw air in from the outside environment or expel air from the inside environment outside. The fan 204 can also be seen through the air inlet 304. The air inlet 304 is positioned on the rear cover 302 and wraps around to the bottom cover 306 of the window fan 100. The bottom cover 306 further includes the sill insert 202 and a base plate 402 for resting on the window sill in front of the window casing. The front cover 104, top panel 108, rear cover 302, bottom cover 306 and left and right end caps 110, 112 all form the fan housing 102, which define a hollow chamber that houses a chamber assembly 502, as further illustrated and described in connection with FIG. 5.

As shown in FIGS. 1 and 3, the air outlet 106 extends past the top panel 108 to create a vertical rail wall 114 that extends horizontally across the top of the window fan 100. This rail wall 114 aligns with and rest against the front of the window rail (not shown) when the window fan 100 is placed in the window opening. Similarly, the sill insert 202 is positioned slightly behind the base plate 402 to allow for a small channel 404 for receiving the front end of an exterior window channel if present in the window sill.

FIG. 5 is a front, side perspective view of the window fan 100 of FIG. 1 with the front cover 104 removed. As seen in FIG. 5, a chamber assembly 502 is positioned within the interior of the fan housing 102. The chamber assembly 502 includes an air duct assembly 504, motor assembly 506 and fan 204, which in the illustrated example is a cross flow blower. The chamber assembly 502 is mounted on the right interior of the window fan housing 102 with a chamber bracket 508, and is mounted to the interior of the fan housing 102 at its left by the motor assembly housing 512, which supports all the component parts of the motor assembly 506, including the gear assembly 710 (FIG. 7) and the left side panel 604 in the interior of the chamber of the fan housing 102.

A controller 510 is also provided for controlling the operation of the motor assembly 506, fan 204, and air duct assembly 504. The controller 501 may be a printed circuit board with a microprocessor or integrated circuit. The controller 510 may include switches and/or buttons that interface with an LCD display for user control. For example, the LDC display may include a power button, speed control buttons, a speech display, mode operation button (i.e. to switch between a fan mode and an exhaust mode), a temperature adjustment button, temperature display, and/or auto mode button (not shown).

FIG. 6 is a front, side front perspective view of the window fan 100 of FIG. 1 with the front cover 104, right end cap 112 and chamber bracket 508 removed. Here, the chamber assembly 502 is again shown to include both the air duct assembly 504 and fan 204. The air duct assembly 502 includes both a right side plate 602 and left side plate 604 for supporting the air duct assembly 504. The right side plate 602 further includes a bearing housing 606 for receiving a fan shaft 802 (FIG. 8) upon which the fan 204 rotates within the air duct assembly 504.

FIGS. 7, 8 and 9 show the chamber assembly 502 with the motor housing 705 and the bearing housing 606 removed, exposing the fan shaft 802 maintained with the bearing housing 606 to allow for the rotation of the fan 202 within the air duct assembly 506. In particular, FIG. 7 is a front perspective view of the left side of the chamber assembly 502 of the window fan 100, with the motor housing removed. FIG. 8 is a front perspective view of the right side of the chamber assembly 502 of FIG. 7, and FIG. 9 is the motor assembly 506 having a motor assembly housing 512 removed.

Fan 202 is positioned within the air duct assembly 504. The air duct assembly 504 includes right and left side panels 602, 604, stability bar 702 spanning from the right side panel 602 to the left side panel 604 and an air duct panel 704, also spanning from the right side panel 602 to the left side panel 604. The air duct assembly 504 rotates about the fan 202 by the motor assembly 506 to open and close the air flow through the air outlet 106 and air inlet 304. The fan 202 rotates within the air duct assembly 504 to produce air flow through the window fan 100. The fan 202 at its left end includes a fan shaft 802 that aligned along the horizontal rotational axis of the fan 202. The fan shaft 802 is rotationally mounted within the bearing housing 606 located on the right side plate 602. At its opposing end, the fan 202 is affixed to motor or drive shaft 902, also in alignment with the horizontal rotational axis of the fan 202. The motor or drive shaft 902 is driven by fan motor 706 (contained with the motor housing 705), which in this example is a reversable motor, that causes the fan 202 to rotate in both directions to blow air into an interior space through the window when rotating in one direction, or exhaust air from the interior space out of the window when rotating in the other direction.

To cause the rotation of the air duct assembly 504 about the fan 202, the motor assembly 506 further includes a second motor or panel motor 708 that rotates a gear assembly 710 affixed to the left side panel 604. In particular, the motor 708 includes a shaft that rotates a small gear 714 that interfaces with, and rotates a large gear 712 that is affixed to the left side panel 604. The panel motor 708 is a reversible motor that is able to independently rotate the air duct assembly 504 about the fan 202 from a open to closed positioned. In the open position, the air duct panel 704 is positioned to freely allow air flow from the air outlet 106 to air inlet 304 or in the opposing direction from the air inlet 304 to the air outlet 106. When in a closed position, the air duct panel 704 is positioned over either the air outlet 106 or the air inlet 304 to block the flow of air through the window fan 100. To avoid the introduction of outside contaminants and insects, the air duct panel 704 is preferrably closed by positioning the air duct panel 704 over the air inlet 304.

FIG. 10 is a front perspective view of the left side of the chamber assembly 502 as shown in FIG. 7 with the fan motor 706 removed to better show the panel motor 708 and gear assembly 710. Here, the fan 204 is still positioned within the air duct assembly 504. The right and left side plates 602, 604, stabilizing bar 702 and air duct panel 704 surround the fan 204. As illustrated, the gear assembly 710 includes a small gear 714 engaging a large gear 710, where the large gear 710 is affixed to the left side panel 604. The panel motor 708 operates to rotate the small gear 714, which then rotates the large gear 710, such that the air duct assembly is rotated about the fan 202. The panel motor 708 may be a reversible motor that can rotate the air duct panel 704 in either direction about the device axis 206. The motor can be controlled to stop the rotation of the air duct panel 704 such that it covers the air inlet 304 or air outlet 106 and close the flow of air through the window fan 100, or it can move the air duct panel 704 away from the air inlet 304 or air outlet 106 to allow air to freely flow through the window fan 100 in either direction (i.e., fan mode or exhaust mode).

FIG. 11 is a side perspective view of the air duct panel assembly 504 of FIG. 10 with the fan 202, panel motor 708 and small gear 714 removed, showing the air duct panel assembly 504 in its most basic form. FIG. 11 illustrates the air duct panel 704 being a curved panel affixed at opposing ends to the right and left side plates 602, 604. Similarly, the stabilizing bar 702 is also affixed at opposing ends to the right and left side plates 604, 602. When the large gear 710 is rotated, the entire air duct panel assembly 504 rotates with the gear independent of the fan 202 rotation. The fan 202 does not rotate with the left and right side plates 602, 604 since the fan 202 on its end facing the motor assembly 506 affixes directly to the drive shaft 902 and on its opposing end, includes a fan shaft 802 that is rotatably mounted in the bearing housing of the right side plate 602 such that it does not rotate with the right side plate 602 but only with the movement of the drive shaft 902 driven by the fan motor 706.

FIG. 12 is a side perspective view of a modular block 1200 that may form part of, or be used in connection with, the window fan 100 of the present invention. The modular foam blocks 1200 are provided to obstructs air or moisture from entering through any open areas on either side of the window fan 100 when installed in a window whose open area is greater than the product length.

The modular blocks 1200 may be of a foam or rubber construction, or similar material, and of a block shape or detailed shape that will fit securely into a wide range of window construction styles from various ages. Each window fan 100 may be accompanied by at least one or a plurality of modular blocks 1200 that may include pairs of blocks, each pair of various lengths, measuring the length across line “L” on FIG. 14, but otherwise similar in construction.

Here, the modular block 1200 is shaped to conform to the profile of a portion of the exterior ends of the first and second end caps 110, 112. For example, the block 1200 may include a block sill insert 1202 that corresponds to the sill insert 202 on the window fan 100. The block may further include a raised front lip 1204 that corresponds to the rail wall 114 created between the air outlet 106 and top panel 108 on the top of the window fan 100 for interfacing with the window rail on the top cover of the window fan 100. The modular block 1200 may further include a ledge 1206 in front of the block sill insert 1202 to align with the channel 404 in the window fan 100 to receive the edge of an exterior channel when present in a window sill.

FIG. 13 is a side perspective view of the right side of the window fan 100 showing the alignment of the modular foam block 1200 with the exterior end of the first caps 112 by overlaying the module foam block 1200 in alignment with the exterior end of the first caps 112. As shown, the profile of the block sill insert 1202 corresponds to the sill insert 202 on the window fan 100, and the raised front lip 1204 corresponds to the rail wall 114 on the top of the window fan 100. Further, the ledge 1206 maintains space, along with the small channel 404 for receiving the front end of an exterior window channel if present in the window sill.

In this manner, the modular foam blocks 1200 fit within the window sill along their bottoms and rest against the front of the window rail at their tops to secure the modular blocks 1200 to the window opening on each side of the window fan 100, in the same way as the window fan 100 fits within the window opening. For illustration, FIG. 14 is a front elevation view of a window fan 100 of the present invention with modular foam blocks 1200 positioned on each side of the window fan.

To allow the window fan 100 to fit in various sized window openings, at least one, or a plurality of modular blocks, which may include one or more pairs of blocks, each pair of various lengths, may be positioned on opposing sides of the window fan 100. Here all the modular blocks 1200, 1500, 1800 and 2100 are of the same height and width and only vary by length. As such, when positioned side by side, all the modular blocks 1200, 1500, 1800 and 2100 will appear the same from the front elevation view, except that they will vary in length. When placed together, they will appear to form a wall on each side of the window fan 100.

As set forth above, the modular blocks may come in various lengths. At least one or a plurality of blocks may be provided that may include pairs of blocks, each of a different length. For example, FIGS. 15-17 show a modular block of a first length, FIGS. 18-20 show a modular block of a second length, and FIGS. 21-23 show a modular block of a third length. In one example, the block in FIGS. 15-17 may be 4 inches in length, the block in FIGS. 18-20 may be 2 inches in length and the block in FIGS. 21-23 may be 1 inch in length. When a pair of blocks of each size is provided, and one of each pair is used per side, a space of 1 inch to 7 inches may be filled on each side of the window fan 100 using all or a combination of blocks. Alternatively, anywhere from a 1 inch to 14 inch space may be filled on either side of the window fan 100, or any combination of space on each side of the window fan 100 from 1 to 14 inches.

FIGS. 15, 18 and 21 each show a side rear perspective view of each modular block 1500, 1800 and 2100 respectively, each having a block sill insert 1502, 1802, 2102 and raised from lip 1504, 1804, and 2104 respectively. FIGS. 16, 19 and 22 each show a side bottom view of the modular foam blocks 1500, 1800 and 2100 of various lengths, each having a block sill insert 1502, 1802, 2102 and raised from lip 1504, 1804, and ledge 1506, 1806 and 2106, respectively. FIGS. 17, 20 and 23 each show a rear view of the modular foam blocks 1500, 1800 and 2100 respectively, each having a block sill insert 1502, 1802, 2102 and raised from lip 1504, 1804, and 2104 respectively of various lengths.

In operation, both the fan 202 and air duct assembly 504 rotate about the same access of rotation, which is the axis of rotation of the drive shaft 902 of the fan motor 706. The first and second or left and right side plates 602 and 604 are rotatably coupled to one another by the stabilizing bar 702 and the air duct panel 704 such that when one side plate is rotated (e.g., side plate 604), the entire air duct assembly 504 rotates about the fan 202 with the fan housing 120. In this manner, the air duct panel 704 is able to move from a first to a second position, or an open to a closed position. When in a closed positioned, the air duct panel 704 is positioned directly behind the air outlet 106 on the front cover 102 of the window fan 100 or alternatively, in front of the air inlet 304 on the rear cover 302 of the window fan 102 to prevent air flow through the window fan 102 and prevent the outside elements from entering the inside space through the window fan 100 when it is not operating. When the window fan 100 is turned off, it is desirable to rotate the air duct assembly to a position blocking either the air outlet 106 or air inlet 304, closing the air outlet 106 or inlet 304 by blocking the flow of air through the window fan 100.

The window fans 100 depth is sized carefully to fit inside of typical window screens, preventing a consumers need to have to remove or adjust a window screen if present. The window fan 100 may feature design/construction features to prevent water from intruding into sensitive areas of the product, along with design elements that transport water off the product and away from the window interior or other water sensitive areas within the product. As described above, the window fan 100 may be accompanied with a modular foam block system that obstructs air or moisture from entering through any open areas to either side of the window fan 100 when installed in a window whose open area is greater than the product length. The inlet and outlet grills may optionally be removable to assist in cleaning and maintenance. The window fan 100 may feature integrated handles to provide ease of installation/removal, temperature sensors, LED and/or manual control and ways to run the power cord discreetly and to either side of the window fan 100.

As previously stated, although the present invention demonstrates the rotation of the air duct assembly 504 using an independent motor 708, those skilled in the art will recognize that the air duct assembly 504 may be rotated manually by a user through the use of the level, switch or rotational knob, for example. Further, while reference may be made throughout the specification to the right or left side of the window fan, those skilled in the art will recognize that the parts within the fan housing 102 may be reversed without departing from the scope of the invention, such that those parts referenced to be affixed to the left may be instead affixed to the right or vice versa.

It will be understood that terms such as “communicate” and “in . . . communication with” (for example, a first component “communicates with” or “is in communication with” a second component) are used herein to indicate a structural, functional, mechanical, electrical, signal, optical, magnetic, electromagnetic, ionic or fluidic relationship between two or more components or elements. As such, the fact that one component is said to communicate with a second component is not intended to exclude the possibility that additional components may be present between, and/or operatively associated or engaged with, the first and second components.

It will be understood that various aspects or details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description is for the purpose of illustration only, and not for the purpose of limitation—the invention being defined by the claims.

Claims

1. A window fan, the window fan comprising: a fan housing having a front panel with an air outlet and a rear panel with an air inlet, the fan housing defining a central chamber;a chamber assembly including a fan rotatably mounted within the chamber and driven by a fan motor and an air duct assembly rotatably mounted within the chamber having an air duct panel moveable from an open to closed position where the air duct panel blocks the airflow through the window fan when in a closed position.

2. The window fan of claim 1 further comprising a second motor for moving the air duct panel from an open to closed position.

3. The window fan of claim 1 where fan is a cross flow blower.

4. The window fan of claim 1 where the fan motor is a reversible motor.

5. The window fan of claim 2 where the second motor is a reversible motor.

6. The window fan of claim 2 where second motor is offset from the fan motor and where the chamber assembly further includes a gear assembly driven by the second motor for rotating the air duct panel.

7. A window fan, the window fan comprising: a fan housing having an air outlet and an air inlet;a cross flow blower fan mounted within the fan housing and driven by a fan motor; andan air duct panel rotatably mounted around the cross flow blower driven by a panel motor, where the panel motor is configured to rotate the air duct panel independent of the cross flow blower fan from an open to closed position, where the motor rotates the air duct panel to blocks the airflow through the window fan when in a closed position.

8. The window fan of claim 7 where fan motor is a reversible motor.

9. The window fan of claim 7 where the panel motor is a reversible motor.

10. The window fan of claim 7 where the panel motor is offset from the fan motor and where the panel motor drives a gear assembly to rotate the air duct panel.

11. A window fan, the window fan comprising: a fan housing having an air outlet and an air inlet;a cross flow blower fan mounted within the fan housing and driven by a fan motor; andan air duct panel rotatably mounted around the cross flow blower driven by a panel motor, where the panel motor is configured to rotate the air duct panel independent of the cross flow blower fan from an open to closed position, where the motor rotates the air duct panel to blocks the airflow through the window fan when in a closed position; anda sill insert positioned on the bottom of the fan housing.

12. The window fan of claim 11 where the fan housing has first and second end caps and where the window fan further includes at least one modular block for positioning on the side of at least one of the first or second end caps.

13. The window fan of claim 12 where the at least one modular block for positioning on the side of at least one of the first or second end caps includes a block sill insert for aligning with the sill insert positioned on the bottom of the fan housing.

14. A window fan, the window fan comprising: a fan housing having a front panel with an air outlet, a rear panel with an air inlet and first and second end caps, the fan housing defining a central chamber;a chamber assembly including a fan rotatably mounted within the chamber and driven by a fan motor and an air duct assembly rotatably mounted within the chamber having an air duct panel moveable from an open to closed position where the air duct panel blocks the airflow through the window fan when in a closed position; andat least one modular block for positioning on the side of at least one of the first or second end caps.

15. The window fan of claim 1 further including a sill insert positioned on the bottom of the fan housing.

16. The window fan of claim 15 where the at least one modular block for positioning on the side of at least one of the first or second end caps includes a block sill insert for aligning with the sill insert positioned on the bottom of the fan housing.

17. The window fan of claim 16 where the at least one modular block for positioning on the side of at least one of the first or second end caps includes a plurality of modular blocks.

18. The window fan of claim 16 where the at least one modular block for positioning on the side of at least one of the first or second end caps includes a plurality of modular blocks having pairs of modular blocks of various lengths.

19. The window fan of claim 14 where fan is a cross flow blower.

20. The window fan of claim 14 where the fan motor is a reversible motor.