WO1992014023A2

WO1992014023A2 - Sound deadening window ventilation apparatus

Info

Publication number: WO1992014023A2
Application number: PCT/US1992/000344
Authority: WO
Inventors: Marcus C. Cox
Original assignee: Cox Marcus C
Priority date: 1991-01-23
Filing date: 1992-01-21
Publication date: 1992-08-20
Also published as: WO1992014023A3

Abstract

A sound deadening window ventilation apparatus (10) is disclosed wherein fresh air is drawn through an air inlet orifice into an upper plenum chamber (12) by means of an electric fan assembly (44), moved through a lower plenum chamber (14) and dispelled from an air outlet orifice (26) is disclosed. Air to be dispelled through the air outlet orifice (26) is moved through a filter (60) held in a filter frame (54). The upper plenum chamber (12) is slidably inserted into the lower plenum chamber (14) such that the outer dimensions of the unit can be varied to fit various sized window openings. Sound traveling through the sound deadening window ventilation apparatus (10) must travel an indirect path and is thereby disrupted. Additional interior baffle plates (580) further disrupt sound and cause it to lose energy. A sound deadening blanket (52, 552) absorbs sound energy as it travels through the plenum chambers (12, 14).

Description

SOUND DEADENING WINDOW VENTILATION APPARATUS

TECHNICAL FIELD The present invention relates generally to ventilation devices and more particularly to apparatus for ventilating a dwelling or other building. The predominant current usage of the sound deadening window ventilation apparatus of the present invention is as a means to allow ventilation while preventing unwanted noise from being admitted.

BACKGROUND ART In the past, when it was desired to admit fresh air into a dwelling, a person could usually just open a window and enjoy a breeze. In all environs except a very few crowded inner cities, this could be accomplished without fear of thereby disturbing one's neighbors or of being disturbed by them. However, in the circumstance of a modern urban environment, considerable noise pollution emanates from the exterior of dwelling areas, particularly from the common areas of apartment complexes and the like. Now, one must frequently choose between living without sufficient ventilation or subjecting one's self to the cacophony outside. In some instances, air conditioning units (wherein a heat exchanger is used to transfer heat from within a dwelling without actually providing a ventilation path between the interior and the exterior) , have taken the place of ordinary ventilation. However, many people find that air conditioning units do not provide a viable substitute for fresh air. Furthermore, the great quantity of power used by air conditioners makes them neither economical nor ecologically conservative. Window fans and the like can, of course, increase ventilation. But they do nothing to solve the problem of outside noise pollution and, indeed, even contribute to the problem by adding noise of their own. Numerous attempts have been made to provide improved ventilation to apartment dwellers, and the like. For instance U.S. Patent No. 4,485,730 issued to Baus and U.S. Patent 4,616,561 issued to Giocastro both teach means for improving fresh air flow into dwellings which can be built into the dwelling at the time of its construction. However, this sort of improvement does little good for renters who are powerless to make this sort of modification to their apartments. U.S. Patent No. 4,042,357 teaches a device for admitting fresh air which can be mounted within a window opening without modification to the window. However, none of the above referenced devices address the need to admit fresh air without also admitting unwanted noise. Clearly, a means for providing proper room ventilation while also preventing the intrusion of sound into the dwelling would be desirable. If the apparatus were also to aid privacy by preventing sounds emanating from the interior from being heard outside, even more benefit could be obtained. All of the prior art ventilation means within the inventor ' s knowledge have allowed the intrusion of sound along with fresh air. No prior art ventilation means to the inventor ' s knowledge has successfully allowed sufficient ventilation without sacrif icing peace and quiet . Al l successful applications to date have either allowed exterior noise to impinge upon the interior, or have themselves contributed a significant amount of noise, or both.

DISCLOSURE OF INVENTION Accordingly, it is an object of the present invention to provide a means for ventilating a dwelling which absorbs sound energy in incoming air. It is another object of the present invention to provide a means for increasing room ventilation which does not itself contribute significantly to noise pollution within a room. It is still another object of the present invention to provide an apparatus f or providing fresh air which is adaptable to a variety of window styles . 1 It is yet another object of the present invention to

2 provide a means for cooling a room which is economical and

3 efficient in operation.

4 It is still another object of the present invention to ' 5 provide a ventilation means which does not require a

6 sacrifice of peace and quiet in the pursuit of fresh air. * 7 It is yet another object of the present invention to

8 provide a ventilation means which is inexpensive to

9 manufacture.

10 It is still another object of the present invention to

11 provide a ventilation means which helps to prevent private

12 conversations and the like from being overheard outside a

13 dwelling.

14 It is yet another object of the present invention to

15 provide a ventilation means which can be installed in a

16 window opening without permanently altering the window.

17 Briefly, the preferred embodiment of the present

18 invention is a box like plenum chamber having, at one end, a

19 fan for forcing air into the chamber from the outside and, at

20 the other end, a discharge port for dispensing fresh air into

21 the interior of a dwelling. Significant benefit is derived

22 from the construction, since intentional misalignment of the

23 air inlet and the fan with the air outlet causes any sound

24 waves present at the inlet/fan combination to be disrupted.

25 Additional sound deadening is provided, in a first preferred

26 embodiment of the invention, by sound absorbing materials.

27 In a alternate equally preferred embodiment of the invention,

28 additional baffles are added within the plenum chamber for

29 further redirecting the air and thus for further disrupting

30 sound waves therein. The presently preferred embodiment of

31 the invention is constructed such that the plenum chamber is

32 formed of two open ended boxes, one of which is fit within

33 the other such that the length of the chamber is adjustable

34 to accommodate window openings of various sizes. Also, the

35 presently preferred embodiment of the invention includes a

36 filter for cleaning incoming air of pollen and dust, which

37 filter is positioned such that it can be easily removed for

38 cleaning from inside the dwelling. An advantage of the present invention is that sound emanating from outside a dwelling or other structure is deadened within the device. A further advantage of the present invention is that the apparatus increases room ventilation without itself adding to ambient noise within the room. Yet another advantage of the present invention is that the inventive room ventilation unit is adaptable to a variety of window styles . Still another advantage of the present invention is that a means for cooling a room which is economical and efficient in operation is provided. Yet another advantage of the present invention is that a user can obtain ventilation without sacrificing peace and quiet . Still another advantage of the present invention is that it is inexpensive to manufacture. Yet another advantage of the present invention is that it assists in maintaining privacy within a dwelling. These and other objects and advantages of the present invention will become clear to those skilled in the art in view of the description of the best presently known modes of carrying out the invention and the industrial applicability of the preferred embodiments as described herein and as illustrated in the several figures of the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partially exploded perspective view of a sound deadening ventilation unit, according to the present invention; FIG . 2 is a partially exploded perspective view of an upper plenum chamber portion of a sound deadening ventilation unit, according to the present invention; FIG . 3 is an exploded view of a sound deadening ventilation unit with a window mounting adaptor plate , according to the present invention ; FIG . 4 is a perspective view of an air redirecting nozz le , according to the present invention , depicting its 1 relationship to a lower plenum chamber; and

2 FIG . 5 is a partial ly exploded perspective view ,

3 similar to FIG. 2 , showing an alternative construction of an

4 upper plenum chamber portion of a sound deadening ventilation ' 5 unit, according to the present invention.

6 ^■ 7 BEST MODE FOR CARRYING OUT INVENTION

8 The best presently known mode for carrying out the

9 invention is a plenum chamber having air inlet means and air

10 outlet means intentionally misaligned so as to disrupt sound

11 waves traveling therein , and further having sound absorbing

12 means for further deadening sound within the device . The

13 predominant expected usage of the inventive sound deadening

14 window venti lation apparatus is in the venti lation of

15 dwellings and off ices , particularly in apartment complexes

16 and the like wherein the ability to admit fresh air without

17 a l so admitt ing no i se from the outs ide environment i s

18 desirable.

19 The sound deadening window ventilation apparatus of the

20 presently preferred embodiment of the present invention is

21 illustrated in a partially exploded perspective view in FIG.

22 1 and is designated therein by the general reference

23 character 10. In many of its substantial components, the

24 ventilation apparatus 10 does not differ significantly from

25 conventional window forced air ventilation devices. The best

26 presently known embodiment 10 of the present invention has an

27 upper plenum chamber 12 and a lower plenum chamber 14. The

28 lower plenum chamber 14 is constructed in the shape of a

29 hollow rectangular box open on one side. The upper plenum 30 chamber 12 is slidably inserted into a lower chamber open end

31 16 of the lower plenum chamber 14 such that the overall

32 height of the ventilation apparatus 10 may be varied

33 depending upon how far the upper plenum 12 is inserted. An

34 adjustment bolt 18 on the upper chamber 12 fits within a slot

35 20 on the lower chamber. An adjustment washer 22 and an

36 adjustment nut 24 are fitted upon the adjustment bolt 18 such

37 that, when the upper plenum chamber 12 is inserted within the

38 lower plenum chamber 14 as much as is desired to properly size the ventilation apparatus 10, the adjustment nut is tightened toward the upper plenum chamber 12 thus preventing further insertion or removal of the upper plenum chamber 12 in relation to the lower plenum chamber 14. An air outlet orifice 26 is located on an interior surface 28 of the lower plenum chamber 14, the interior surface 28 being that surface of the upper plenum chamber 12 which faces inward toward the interior of a room (not shown) when the window ventilation device 10 is in use. A decorative grill 30 is loosely fitted within the air outlet orifice 26. As will be discussed hereinafter, the decorative grill 30 will be removed in some applications of the window ventilation device 10. Referring now to FIG. 2, wherein is shown an exploded perspective view of the upper plenum chamber 12. In the view of FIG. 2 it can be seen that the upper plenum chamber 12 has a chamber body 32 having an upper back 34, an upper left side 36, an upper right side 38 and an upper top 40. An air inlet orifice 42 is located in the upper back 34 near the upper top 40. An electric fan assembly 44 having a fan inlet 46 and a fan outlet 48 is rigidly affixed within the chamber body 32 with the fan inlet 46 positioned over the air inlet orifice 42 such that air is drawn into the fan assembly 44 through the upper back 34. The fan outlet 48 is positioned to dispel air into the interior of the upper plenum chamber 12. An upper plenum cover 50 is provided to enclose the chamber body 32 on the interior side 28. The electric fan assembly 44 is an ordinary ventilation fan of the type generally sold as bathroom ventilation fans. While the best presently known embodiment 10 of the invention employs a blade type fan, the inventor has found that a cage type or other sort of electric fan can be successfully utilized in the application. In the presently preferred embodiment 10 of the invention, the electric fan assembly 44 is turned on and off by means of an in-line switch located in an electric cord (not shown) supplying power to the electric fan assembly 44. Other possibilities exist within the scope of the invention for providing operator control means for the electric fan assembly 44 including that of placing a multi-position switch (not shown) in or on the upper plenum cover 50 connected to the electric fan assembly 44 so as to provide the possibility of multi-speed control of the electric fan assembly 44. The upper plenum cover 50 is rigidly affixed to the chamber body 32 such that the assembled upper plenum chamber 12 is in the form of a hollow rectangular box open at the bottom. A comparison of the view of FIG. 1 with the view of FIG. 2 will reveal that air drawn into the air inlet (FIG 2) and will slightly pressurize the upper plenum chamber 12 and the lower plenum chamber 14 and eventually be dispelled from the air outlet orifice (FIG 1) . Referring again to FIG. 2, a sound deadening blanket 52 is placed within the upper plenum chamber 12. The sound deadening blanket 52 is made of a non toxic synthetic foam rubber type material specifically constructed for sound insulation purposes. This material is commonly available and is well known to those skilled in the art. The sound deadening blanket 52, when placed inside the chamber body 32 is formed roughly in the shape of a tube through which air forced from the fan outlet 48 toward the air outlet orifice 26 (FIG 1) must travel. Since any sound waves entering the window ventilation device 10 through the fan inlet 46 cannot travel in a straight line toward the air outlet orifice 26, they must necessarily be reflected at least once from at least one portion of the sound deadening blanket 52. Thus, any sound entering the electric fan assembly 44 or created therein is considerably reduced both in volume and in annoying high frequency content before reaching the air outlet orifice 26. In the presently preferred embodiment 10 of the invention, a filter frame 54 is rigidly attached inside the chamber body 32 as depicted in FIG. 2. The filter frame 54 consists of an upper rail 56 and a lower rail 58 positioned so as to receive a filter 60 which can is inserted through a filter insertion port 61. In the presently preferred embodiment 10 of the invention, the filter 60 is a replaceable unit which may be interchanged with other such filters 60 according to the needs of the user. While the best presently preferred embodiment 10 of the invention utilizes a filter 60 which is a simple passive conventional filtering means for filtering pollen, dust, and the like from the air, it is anticipated that variations of the filter 60 can be supplied which include a conventional ionizing filter or a conventional heating element. Furthermore, it is anticipated that less costly variations of the invention might be supplied which do not include the filter 60. The filter 60 is inserted through the filter insertion port 61 on the interior surface 28 such that it may be removed from the filter frame 54 for cleaning from a room interior (not shown) . As can be seen in the drawing of FIG. 2, the filter 60 can be slidably inserted through the filter insertion port 61 between the upper rail 56 and the lower rail 58 such that any air moving from the fan outlet 48 to the air outlet orifice 26 (FIG 1) must pass through the filter 60. The inventive window ventilation device 10 has been described herein as being adjustable to fit various window size openings. Of course, this feature is not a necessary part of the invention, and it is contemplated by the inventor that units of a fixed size may be produced to accommodate specific applications. While the inventor has successfully employed several arrangements for mounting the window ventilation device 10 in a window, the best presently known embodiment 10 employs a window adaptor 62, as is depicted in FIG. 3, for the purpose. The window adaptor 62 is rigidly affixed to the window ventilation device 10 with a weather strip 64 therebetween. The weather strip 64 is a commonly available rubber-like piece which fills ary gaps created by any differences in the size of the upper plenum chamber 12 and the lower plenum chamber 14, and thus creates a weather tight seal between the window adaptor 62 and the window ventilation device 10. The window adaptor 62 is a flat plate having a first rail 66 and a second rail 68 which rails 66 and 68 fit on either side of a window frame 70, thus preventing the window ventilation device 10 from falling either inward or outward. In some applications, it may be desirable to install a second window adaptor plate (not shown) on the opposing side (not shown in the view of FIG. 3) of the window ventilation unit 10. The inventor has also found that variations of the window adaptor 62, including a variation having only a single rail 66 or 68 may be desirable for installation of the window ventilation device 10 in specific window applications. It is anticipated by the inventor that a conventional clamping device (not shown) can be used to clamp the window adaptor 62 to the window frame 70, thus securing the window frame 70 in a closed position as protection against unauthorized entry. Heretofore, a method for fastening various components of the window ventilation device 10 has not been discussed. In the best presently known embodiment 10 of the invention, the upper plenum chamber 12 and the lower plenum chamber 14 are constructed of plywood, and the component parts thereof are fastened together using wood screws (not shown) , and the electric fan assembly 52 and the filter frame 30 are also fastened to the window ventilation device 10 using wood screws (not shown) . However, the inventor does not regard the material from which the upper plenum chamber 12 and the lower plenum chamber 14 are constructed to be a unique aspect of the present invention. Indeed, it is contemplated that future window ventilation devices 10, according to the present invention, will be constructed of sheet metal or of a synthetic plastic material, and that different fastening means appropriate to the materials used will be employed in the construction. An additional feature of the best presently known embodiment 10 of the invention is depicted in FIG. 4. The lower plenum chamber 14 is shown with an air redirecting nozzle 72. The air redirecting nozzle 72 is a hollow structure through which air from the air outlet orifice 26 is redirected to exit through a redirecting output orifice 74. The air redirecting nozzle 72 has an air input end 76 which is slidably inserted into the air outlet orifice 26 (the decorative grill 30 (FIG 1) having been removed) . Within the air redirecting nozzle 72 air is channeled from the air input end 76 to the redirecting output orifice 74 through a narrow redirecting channel 78. The shape of the air redirecting nozzle 72 is a function of its purpose, which is to allow a window shade (not shown) to be lowered without blocking the flow of air from the air outlet orifice 26. As can be seen in the drawing of FIG. 4, the redirecting output orifice 74 extends below any portion of the lower plenum chamber, thus providing a means for expelling air from below window level. While the best presently known embodiment 10 of the invention utilizes the combination of a construction which does not permit straight line travel of sound waves through the window ventilation device 10 and the sound deadening blanket 60 to prevent the intrusion of sound into the interior of a dwelling, the inventor has found that an equally preferred alternate embodiment of the invention incorporating an alternative upper plenum chamber 512, as depicted in the FIG. 5, may in fact provide even greater benefit. As is shown in the drawing of FIG. 5, the alternative upper plenum chamber 512 is quite similar to the upper plenum chamber 12 of the presently preferred embodiment 10 of the invention, having a chamber body 532 with an upper back 534, an upper left side 536, an upper right side 538 and an upper top 540. Also, an air inlet orifice 542, an electric fan assembly 544 and an upper plenum cover 550 of the alternative upper plenum chamber 512 are not unlike those respective component parts of the presently preferred embodiment 10 of the invention. A sound deadening blanket 552 of the alternative upper plenum chamber 512 is similar to the sound deadening blanket 52 of the preferred embodiment 10 of the invention, although the sound deadening blanket 552 of the alternative upper plenum chamber 512 is somewhat smaller, as will be discussed hereinafter. The alternative upper plenum chamber 512 includes a plurality (in this instance, two) of interior baffle plates 580. The interior baffle plates 580 are projections from the back 534 and one side 536 or 438 which extend into the interior of the chamber body 532 and partially, but not completely, impede the flow of air therethrough. The interior 1 baffle plates 580 serve to extend one of the inventive

2 principles by causing any sound waves traveling within the

3 alternative upper plenum chamber 512 to travel an even more

4 indirect path than would be possible were the interior baffle * 5 plates 580 not included. As one familiar with the art will

6 realize, each time sound waves are redirected (as by the

⁽ 7 interior baffle plates 580) they have a tendency to lose some

8 of their energy to the environment. This is particularly

9 true of annoying higher frequency sounds within the audio

10 spectrum. As can be seen in the view of FIG. 4, the sound

11 deadening blanket 552 of the alternative upper plenum chamber

12 512 is reduced in size, as compared to the sound deadening

13 blanket 52 of the presently preferred embodiment 10 of the

14 invention, in order to accommodate the interior baffle plates

15 580.

16 It should be noted that the alternative upper plenum

17 chamber 512 is depicted in FIG. 4 without provision for a

18 filter 60 (FIG 2) , although a filter 60 could certainly be

19 employed in combination with the alternative upper plenum

20 chamber 512 as described heretofore in conjunction with the

21 upper plenum chamber 12.

22 As is shown above, in great part, the sound deadening

23 window ventilation apparatus 10 according to the present

24 invention closely resembles prior art conventional forced air

25 window ventilation devices in many respects. The substantial

26 difference exists in the inclusion of the upper plenum

27 chambers 12 and 14 for intentionally misaligning the air

28 inlet orifice 42 and 442 with the air outlet orifice 26, and

29 further in the provision of additional sound baffles 580

30 and sound deadening material 52 and 552. No significant

31 changes of materials are envisioned nor are any special

32 constructions required.

. 33 Various modif ications may be made to the invention

34 without altering its value or scope. For example, while the

, 35 sound deadening window ventilation apparatus of the present

36 invent ion is depicted herein as having the upper plenum

37 chamber 12 and the lower plenum chamber 14 constructed as two

38 divisible parts , this construction is not necessary to the invention and a single box like plenum chamber could easily be substituted for the combination. Similarly, additional features could be added while still staying within the scope of the invention. For instance, a thermostat could be added to cause the electric fan assembly 44 to operate at a preset temperature, or a burglar alarm could be installed on the unit to sound a warning if it is disturbed as by someone attempting to remove the unit from the window to thereby gain access to the residence. Another conceivable change is to employ any of a great variety of conventional means for mounting the sound deadening window ventilation device 10 in a variety of different types and sizes of window openings. Furthermore, a locking means could be added to the present invention to prevent its removal from the window opening. All of the above are only some of the examples of available embodiments of the present invention. Those skilled in the art will readily observe that numerous other modifications and alterations may be made without departing from the spirit and scope of the invention. Accordingly, the above disclosure is not intended as limiting and the appended claims are to be interpreted as encompassing the entire scope of the invention.

INDUSTRIAL APPLICABILITY

Forced air window ventilating devices are widely used in supplying fresh air to the interiors of dwellings and other buildings. The predominant current usage of the inventive sound deadening window ventilation apparatus is for ventilating apartments in relatively noisy apartment complexes. The sound deadening window ventilation apparatus of the present invention may be utilized in any application wherein conventional window ventilation devices are used. The main area of improvement is in the combination of an indirect sound path and sound deadening material along with a forced air plenum ventilation apparatus. It is anticipated that many users of the inventive sound deadening window ventilation devices will be apartment dwellers who have a need to obtain a means permitting themselves to obtain fresh air free of unwanted noise pollution which means does not damage nor permanently alter the structure to which is attached. Therefore, the various optional constructions discussed herein combine to become a key feature of the invention. Indeed, the fact that the inventive combination is adaptable, as described herein, to a variety of means for fitting and holding into a window opening is a primary benefit of the present invention. Since the sound deadening window ventilation devices of the present invention may be readily constructed and are easily adapted to a variety of window sizes and types, it is expected that they will be acceptable in the industry as substitutes for conventional window fans and air conditioning and filtration units. Furthermore, since the inventive sound deadening window ventilation devices are inexpensive to manufacture and to operate, it is anticipated that they will be widely accepted as an alternative to leaving a window open to obtain fresh air, especially in crowded urban environs. For these and other reasons, it is expected that the utility and industrial applicability of the invention will be both significant in scope and long-lasting in duration.

Claims

IN THE CLAIMS

1. A ventilation apparatus for admitting fresh air into a dwelling, including: a box adapted to be removably fit within a window opening; an air admittance port located within a first outer surface of said box for admitting air into said box from outside the dwelling; an air discharge port located within a second outer surface of said box, said second outer surface being an exterior surface of said box opposed to said first outer surface, for discharging air into the dwelling; wherein the air discharge port is misaligned in relation to said air admittance port such that sound waves entering the air admittance port and traveling through said box will be forced to travel an indirect path in order to reach the air discharge port.

2. The apparatus of claim 1, and further including: a sound absorbing blanket positioned within said box such that energy is dissipated into the sound absorbing blanket from sound waves traveling through said box and impinging upon the sound absorbing blanket.

3. The apparatus of claim 1, and further including: at least one sound baffle positioned on the interior of said box such that sound waves moving between the air admittance port and the air discharge port are prevented from traveling in a straight line and are thereby disrupted.

4. The apparatus of claim 1, and further including: an electric fan connected to the air admittance port for forcing air through the box and out of the air discharge port. //// ////

5. The apparatus of claim 1, and further including: a filter positioned such that air passing out of the discharge port must pass through said filter, for filtering dust and pollen from the fresh air.

6. The apparatus of claim 5, wherein: the filter is insertable from inside the dwelling through said second outer surface such that it may be easily removed for cleaning and replacement.

7. The apparatus of claim 1, wherein: said box includes a first partial box portion and a second partial box portion, each of said partial box portions having an open end, said first partial box portion being smaller than said second partial box portion such that said first partial box portion is slidably inserted within said second partial box portion with the open end of said first partial box portion inside said second partial box portion such that two partial box portions form said box and such that a dimension of said box may be varied by sliding said first partial box portion in and out of said second partial box portion, thus enabling a user to fit said box within a variety of different sized window openings.

8. The apparatus of claim 7, and further including: a window adaptor attached to a side of said box, said window adaptor having at least one rail suited for abutting a window frame such that said box is prevented from moving past said window frame when said window frame is closed against said box, thus preventing removal of said box from said window frame.

9. The apparatus of claim 1, and further including: an air diversion means for diverting air from the air discharge port first in a downward direction and then outward away from the ventilation apparatus, said air diversion means being a hollow tubular structure with an input end adapted to fit within the air discharge port and an output end positioned in relation to the input end such that the air output end is lower than the air input end and also such that air exiting from the output end will be moving in the same general direction as air initially entering the input end.

10. An improved window ventilating unit, including: a hollow enclosure for insertion within a window opening, said enclosure having an outside wall, an inside wall, and a plurality of side walls, said walls enclosing an interior air space; an air inlet aperture within said outside wall; an air outlet aperture within said inside wall; and a plurality of sound baffles within said interior air space for preventing sound waves from traveling directly from the air inlet aperture to the air outlet aperture.

11. The improvement of claim 10, wherein: said sound baffles disrupt air flow within the hollow enclosure such that sound waves entering the air inlet aperture are substantially dissipated within the hollow enclosure.

12. The improvement of claim 10, and further including: an air flow urging means positioned so as to draw air into the hollow enclosure through the air inlet aperture from outside the window and to force air out of the hollow enclosure through the air outlet aperture.

13. The improvement of claim 12, wherein: said air flow urging means is reversible such that air may optionally be drawn into the hollow enclosure through the air outlet and discharged through the air inlet. //// ////

14 . The improvement of claim 10 , and further including: a sound deadening material positioned within the hollow enclosure such that air traveling through the hollow enclosure must pass by said sound deadening material .

15. The improvement of claim 14, wherein: said sound deadening material is a synthetic foam capable of dissipating sound energy.

16. The improvement of claim 10, wherein: the hollow enclosure has an inner portion which is slidably inserted into an outer portion such that the size of the hollow enclosure may be varied in one dimension by sliding the inner portion relative to the outer portion.

17. A window ventilating unit, having a hollow box with an air inlet on an outward facing side of the hollow box and an air outlet on an opposed inward facing side, wherein: the air inlet is offset from the air outlet such that air traveling between the air inlet and the air outlet must follow a nonlinear path, such that any sound waves entering the air inlet are necessarily reflected from at least one of a plurality of interior sides of the hollow box.

18. The ventilating unit of claim 17, wherein: at least one of said plurality of walls is at least partially covered with a sound deadening blanket.

19. The ventilating unit of claim 17, and further including: a plurality of air baffles interposed between the air inlet and the air outlet for deadening sound waves present within air moving within the hollow box. //// //// ////

20. The ventilating unit of claim 17, and further including: an electric fan mounted within the hollow box for pulling air into the air inlet and pushing air out of the air outlet.