DESC:FIELD OF THE INVENTION:
The present invention relates to an indoor air ventilation apparatus, more particularly a fenestration integrated fresh air ventilation apparatus for adequate air exchange and air circulation.

BACKGROUND OF THE INVENTION:
Ventilation is the movement of outdoor air into a building or room or an enclosed space. Air ventilation inside a closed space provides healthy air, thereby reducing pollution and stagnated air inside the enclosed space. The term ‘fresh air’ is commonly used to refer to air that is outside (or from outside) a building or enclosed space, as opposed to that which is inside. In order to ensure a good supply of fresh air, buildings need to be properly ventilated. Sometimes, air that is not fresh is referred to as 'stale air'.
As the world develops, we continuously are observing a rise in construction of various types such as residential areas, commercial spaces, and the like. Increasing building construction has led to construction of a lot of cramped spaces. This leads to fresh air ventilation problems in rooms or closed spaces. Effectively, the indoor air freshness of enclosed spaces has deteriorated due to no air exchange and carbon dioxide build up inside the space. Fresh air is an essential component of any enclosed space as it increases oxygen availability, maintains comfortable temperature, increases energy levels, humidity and also reduces moisture, and the like in any enclosed space.
There are three methods of ventilating an enclosed space - natural ventilation, mechanical ventilation and hybrid ventilation. When natural forces such as wind and thermal buoyancy caused due to air density differences, it drives outdoor air inside enclosed spaces, this is called natural ventilation. In mechanical ventilation, mechanical devices such as fans and the like are directly installed on ceilings to provide artificial ventilation. Hybrid air ventilation uses natural driving forces to provide a desired flow rate and uses mechanical ventilation when the flow rate is too low. Depending on the current environmental issues such as global warming, ozone depletion and higher energy consumption, spaces must have provisions that explore natural ventilation rather than forced air conditioning. It is noted that mechanical ventilation controls five different parameters namely oxygen content, carbon dioxide and moisture, odor and contaminants, bacteria and heat.
Fans constitute a part of mechanical ventilation. However, fans recirculate the air present in a room back within a space. Further, fans do not bring in fresh air or remove stale air from an enclosed space. A common side effect of prolonged exposure to direct airflow from fans is that they lead to draft discomfort leading to headaches, stiff necks, and the like to the occupant. On the other hand, air conditioners also simply recirculate air in an enclosed space. However, air conditioners have added features of temperature control. There are various side effects to prolonged use of air conditioners. These include dehydration, temperature induced stress, caused due to drastic shifts between indoor cold temperatures and outdoor hot environments and the like. Further, poor maintenance of air conditioners also leads to moisture buildup in filters and ducts that leads to mold build up and respiratory issues.
In colder climates, a custom air ventilation system is required for winters when the temperatures fall below 0?. Various different solutions have been developed for this purpose such as a window air ventilation system with an integrated waste heat recovery unit. Here, used up warm air is routed to a heat exchanger and cool air is brought in from outside through this heat exchanger and warmed up. Another type of ventilation system is window fans being introduced to windows that introduces fresh air into the enclosed space. These conventional air ventilation systems are built for colder climates, specifically for maintaining the warmth inside a room during winters. They provide air movement with minimum inflow percentage.
The US Patent US11719037B2 to Farnes, Brian Michael et al. discloses a fenestration assembly that includes a fenestration frame with an operator and a translucent panel. There includes a prescription module to provide difference between the specified light prescription and the ambient light. According to the difference, the controller operates one light modulation element. However, this patent fails to teach any air ventilation assembly in the fenestration that exchanges air inside the room with outside air as that of the present invention.
The European Patent Application EP2882920A1 to Glover, Michael et al. teaches an energy efficient fenestration assembly that includes a sliding glass assembly that is received in a pocket of the fenestration assembly with an actuator and a motor that controls the blinds on the fenestration. However, this patent fails to teach any air ventilation assembly in the fenestration that exchanges air inside the room with outside air as that of the present invention.
Therefore, there is a need for an integrated air ventilation apparatus that is integrated in fenestrations. There is also a need for fenestration integrated fresh air ventilation apparatus that is hidden from the inner side of the enclosed space and that provides fresh, natural air to the enclosed space, while simultaneously removing stale air.

SUMMARY OF THE INVENTION:
The present invention discloses a fenestration integrated fresh-air ventilation apparatus for an enclosed space including a first module that is mounted at an interior side of a fenestration and including a frame with at least a first slit for supplying outdoor air to the enclosed space and at least a second slit for discharging indoor air. The present invention includes a second module that is mounted at an exterior side of the fenestration and includes a first unit that is aligned with the first slit, and the second unit aligned with the second slit and a third unit housing a motor, a controller, and an electric circuit. Further, the second module includes a curvature that is an arch of a curvature of an angle depending upon the radius of the cross-flow fan that is enclosed in the first unit and enables laminar airflow within the enclosed space.
The present invention also includes a cross-flow fan disposed in the first unit and driven by the motor to draw outdoor air through the first unit into the enclosed space. The first unit also includes a membrane positioned at the first unit to permit passage of air while restricting entry of particulate matter; wherein the apparatus is configured to simultaneously introduce outdoor air into the enclosed space and expel indoor air to the external environment and achieve equilibrium with the air temperature in the outer environment while being integrable into a conventional fenestration frame.
The cross-flow fan of the present invention is positioned within the first unit that forms high pressure zones and allows a single exit for fresh air through the first slit, thereby generating a laminar air flow throughout the enclosed space. The apparatus of the present invention is a modular apparatus such that it is integrable onto any size of fenestration. Further, the first module of the apparatus presenting only a visible frame with the first slit and second slit when installed, the remainder being concealed within the fenestration. The membrane of the apparatus includes a removable particulate filter or insect screen.
The width of the second module of the present invention is approximately 135mm and the width of the first module is approximately between 75mm and 120mm. Further, the width of the first gap is approximately 8mm and the width of the second gap is approximately 4mm leading to a pressure zone for fresh air being formed within the gaps, leading to a laminar air flow within the enclosed space.
The apparatus of the present invention is integrably positionable onto any side of the fenestration as per fresh air requirement of the enclosed space. Further, a plurality of apparatus of the present invention are stackable onto each other to modularly integrate multiple apparatus into a single fenestration. Also, the membrane being a semi-permeable membrane that allows entry of fresh air into the apparatus without any of the particulate matter present in the outer environment. Furthermore, the cross-flow fan is suspended by a connector and pivot bearing to reduce vibration and noise.
The sensors within the apparatus of the present invention sense at least one parameter selected from temperature, humidity, wind speed, carbon dioxide concentration, particulate concentration or volatile organic compounds. Further, the controller automatically adjusts the fan speed based on sensor inputs to achieve a predetermined air-exchange rate. The apparatus also includes a display regulator that is operable from the interior of the enclosed space to display sensed parameters and allow manual adjustment of fan speed. Also, the exhaust unit includes at least one of a back-draft damper, a rain louver, or a baffle. The apparatus also includes tool-free access via a removable cover plate for servicing the motor, controller or filter. The apparatus of the present invention has wireless connectivity for remote control, scheduling, and diagnostics.
The apparatus of the present invention is dimensioned to achieve a minimum of four air changes per hour in a standard room volume in accordance with building code requirements. The cross-flow fan and first unit are configured to produce an airflow rate of at least 96 cubic feet per minute (CFM) in a standard room.
The present invention also discloses a method of ventilating an enclosed space using the apparatus including several steps. The first step of activating the controller by receiving user input or sensor input. The second step of driving the motor to rotate the cross-flow fan and a third step of drawing outdoor air through the membrane of the first unit into the enclosed space via the first slit. The next step of discharging indoor air from the enclosed space through the second slit to the second unit and a final step of repeating the above steps to maintain continuous air exchange.

BRIEF DESCRIPTION OF DRAWINGS:
The objectives and advantages of the present invention will become apparent from the following description read in accordance with the accompanying drawings wherein,
FIG. 1 shows the practical positioning of a fenestration integrated fresh air ventilation apparatus of the present invention;
FIG. 2 shows a perspective view of the apparatus of FIG. 1;
FIG. 3 shows a back perspective view of the apparatus of FIG. 1;
FIG. 4A shows a side sectional view of the apparatus of FIG. 1;
FIG. 4B shows a perspective view with internal components of the apparatus of FIG. 1;
FIG. 5 shows an exploded view of the apparatus of FIG. 1;
FIGS. 6A, 6B, 6C, 6D shows the formation of curvature of the second module of the apparatus of FIG. 1;
FIG. 7 shows an airflow diagram of the air flowing through the apparatus and a cross-flow fan of FIG. 1;
FIG. 8A shows a flowchart of the air flow through the apparatus of FIG. 1;
FIG. 8B shows a flow of the controller for operation of the apparatus of FIG. 1; and
FIGS. 9A and 9B show experimental data with respect to the operation of the apparatus of FIG. 1.

DESCRIPTION OF THE INVENTION:
References in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
References in the specification to “preferred embodiment” means that a particular feature, structure, characteristic, or function described in detail thereby omitting known constructions and functions for clear description of the present invention.
The foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed and obviously many modifications and variations are possible in light of the above teaching.
Referring to FIG.1, the positioning of a fenestration integrated air ventilation apparatus (100), hereinafter referred to as an apparatus (100) is described. The apparatus (100) is positioned onto one side of a standard fenestration (84) within an enclosed space (80). The apparatus (100) is positioned on one vertical side of the standard fenestration (84) such that both the standard fenestration and the apparatus (100) are operational as per the user’s requirement optionally at the same time.
The apparatus (100) is securely positioned in between the wall and the fenestration frame (86). The positioning of the apparatus (100) is such that is remains concealed and only the outer frame of the apparatus (100) is visible from the inside of the room.
Referring to FIGS. 2 and 3, the front and back perspective views of the apparatus (100) is described. The apparatus (100) includes a first module (204) and second module (208) wherein the first module (204) is positioned on the inner side of the enclosed space (80) and the second module (208) is positioned on the outer side of the enclosed space. Further, the second module (208) is not visible from the inside of the enclosed space. The second module (208) of the apparatus (100) is an exoskeleton that encloses the several components of the apparatus (100). The second module (208) is a curved structure that extends into the inner half of the first module (204) of the apparatus (100).
In accordance of the present invention, the first module (204) includes a first slit (212), a second slit (216) and a frame (220). In accordance with the present invention, the frame (220) encloses the first slit (212) and the second slit (216). The first slit (212) is positioned on the upper end of the frame (220) whereas the second slit (216) is positioned on the lower end of the frame (220). Further, a plate (224) is positioned between the first slit (212) and the second slit (216). The plate (224) acts as a packaging for preventing any dust or particulate matter to enter into the apparatus (100).
The second module (208) of the apparatus (100) is approximately a semi-circular cylinder that is positioned on the outer side of the fenestration of the enclosed space. The semi-circular shape of the second module (208) is further an arch shaped curvature. The second module (208) includes a first unit (228), a second unit (232) and a third unit (236). The first unit (228) is positioned on the top portion of the second module (208) such that it corresponds to the first slit (212). Further, the second unit (232) is positioned on the lower end of the second module (208) such that it corresponds to the second slit (216) of the first module (204). Similarly, the third unit (236) is positioned between the first unit (228) and the second unit (232) such that it corresponds to the packing plate (224) of the first module (204).
Further, the first unit (228) and the second unit (232) are cavities that are open from one side of the second module (208). Particularly, the first unit (228) and the second unit (232) are open from the straight sided end of the second module (208) that is approximately opposite to the curved end of the second module (208). In accordance with the present invention, a membrane (308) is positioned over the first unit (228) such that the open cavity of the first unit (228) is covered. The membrane (308) is preferably a selectively permeable membrane that keeps out particulate matter, allowing fresh air to enter through the first unit (228). The first module (204) and the second module (208) are connected to each other such that the cavity within the first unit (228) extends into the first slit (212). Similarly, the cavity within the second unit (232) extends into the second slit (216).
Also, the first unit (228) encloses a cross-flow fan (304) within it. The cross-flow fan (304) rotates such that fresh air from the outer environment enters into the apparatus (100) through the first unit (204) and into the enclosed space via the first slit (212). The second unit (232) acts as an output unit such that it allows the exit of stale air from the enclosed space to the outer environment. The is positioned such that it receives air from the outer environment and pushes it into the room in which the apparatus (100) is fitted through the first slit (212) of the first module (204) of the apparatus (100).
Furthermore, the third unit (236) includes a cover plate (312) that seals the central portion of the apparatus (100). The third unit (236) encloses various components such as the electrical circuit, controller, sensors and the like (NOT SEEN). The cover plate (312) is removably positionable on to the third unit (236). The cover plate (312) acts as an entry for conducting maintenance cycles and the like. The second module (208) is an arch shaped curvature, such that one side is a rounded curve and the remaining two sides define a right angle. The second module (208) encloses several components of the apparatus (100) that allow flow of fresh air into the enclosed space through the first slit (212) of the first module (204).
In accordance with the present invention, the width of the second module (208) is approximately 135mm. Further, the approximate width of the gap within the frame (220) is approximately 40 mm. It is noted that the height of the apparatus (100) is dependent on the height of the fenestration onto which the apparatus (100) is to be fitted. However, preferably, the minimum height of the apparatus (100) is noted to be approximately 450mm. Further, the width of the first module (204) is dependent on the width of the fenestration on to which the apparatus (100) is to be fitted. However, preferably, the width of the first module (204) is approximately between 75mm to 120mm. Furthermore, the inner and second modules (204, 208) of the apparatus (100) are preferably made of metal such as aluminum. However, a person skilled in the art will appreciate that the apparatus (100) may be made of any other material such as wood, plastic, carbon polymer and the like as per the user’s requirements.
The apparatus (100) is securely positioned in between the wall and any standard fenestration frame. The positioning of the apparatus (100) is such that it remains concealed and only the frame (220) with the first vertical slit (212) and the second slit (216) of the apparatus (100) is visible from the inside of the room.
Referring to FIGS. 4A and 4B, the sectional view of the apparatus (100) is described. The cross-flow fan (304) is enclosed within the first unit (228) that rotates through actuation of a motor (404). The third unit (236) of the apparatus (100) encloses the motor (404) with a connector (408). The motor (404) is positioned in the upper portion of the third unit (236) such that the motor (404) is connected to the cross-flow fan (304). The connector (408) is preferably a connector pin like structure that connects the motor (404) to the cross-flow fan (304) of the apparatus (100). In accordance with the present invention, the cross-flow fan (304) includes a plurality of blades (412). The blades (412) are vertical blades that are positioned in a whorl arrangement that efficiently pull fresh air into the first unit (228). Further, the cross-flow fan (304) includes a plurality of tiers. Each of the tiers includes a specific arrangement of the blades (412), leading to formation of multiple whorls of blades positioned onto the cross-flow fan (304).
Further, the cross-flow fan (304) is suspended within the first unit (228) via a suspension mechanism. The suspension mechanism includes a connector (416) and a pivot (420). The connector (416) is preferably a triangular connector that is positioned above the cross-flow fan (304) and is connected to the top of the first unit (228). The pivot (420) is preferably a pivot ball-bearing that connects the cross-flow fan (304) to the connector (416). The suspension mechanism fixes the cross-flow fan (304) in position and ensures free rotation of the cross-flow fan (304) in either direction.
The third unit (236) further includes a controller (424) and a circuit (428). The controller (424) is positioned approximately centrally within the third unit (236) and is connected to the other components of the apparatus (100) such as the cross-flow fan (304), motor (404), sensors, regulators and the like through the electric circuit (428). The apparatus (100) further includes a display regulator (432) and a plurality of sensors (436). The display regulator (432) is positioned on the side of the fenestration (86) such that it is visible and operable from the enclosed space. The display on the display regulator (432) preferably displays the speed of rotation of the cross-flow fan (304), the temperature of the enclosed space, wind speed and the like. The regulator of the display regulator (432) preferably is a rotatable knob that when rotates allow change in speed of the cross-flow fan (304). It is noted that in other embodiments of the present invention, the display regulator (432) may be a touch screen with a touch pad, a display with buttons or any other type of display regulator anticipated by a person skilled in the art.
Further, the apparatus (100) includes a plurality of sensors (436) that sense various parameters such as temperature, wind speed, humidity etc. The present embodiment includes a pair of sensors (436) such that one sensor of the pair is positioned on the outer side of the apparatus (100) to sense parameters of the outer environment. A second sensor of the pair of sensors (436) is positioned on the inner side of the fenestration (86) such that it is visible and operable from the enclosed space. The second sensor senses parameters of the enclosed space. The pair of sensors (436) together allow the controller (424) to recommend the speed of the cross-flow fan (304) as per the temperature requirements of the user.
The pair of sensors (436) sense parameters such as temperature, humidity, wind speed and the like. The pair of sensors (436) include temperature sensors that preferably are thermocouples, thermistors, resistance temperature detectors (RTDs) and the like. The pair of sensors (436) also include wind speed sensors that preferably are anemometers, wind direction sensors of any type such as cup, propellor, vane and the like. The pair of sensors (436) also include humidity sensors such as capacitive, resistive, thermal sensors and the like. However, a person skilled in the art will appreciate that the sensors may also sense other parameters such as particulate matter sensors, gas sensors, Carbon dioxide (CO2) sensors, pressure sensors and any other sensors anticipated by a person skilled in the art.
Now referring to FIG. 5, the exploded view of the apparatus (100) is described. The apparatus (100) includes a first closure (504), a second closure (508) and a pair of scaffolds (512) that enclose the components of the first module (204) and second module (208) of the apparatus (100). The first closure (504) is a top closure and is fitted onto the upper end of the first unit (228) of the apparatus (100) by a plurality of screws. Similarly, the second closure (508) is a bottom closure that is fitted onto the lower end of the second unit (232). The pair of scaffolds (512) are preferably a L shaped scaffold. The pair of scaffolds (512) fit onto the edge of the existing fenestration such that the apparatus (100) is able to integrate into the existing available space. Further, the scaffolds (512) seal the apparatus (100), thereby preventing any air leakage. This ensures optimal air pressure through the first slit (212) of the first module (204) into the enclosed space.
In accordance with the present invention, each of the first unit (228), second unit (232) and the third unit (236) is formed from a plurality of panels. The first unit (228) includes a first panel (516), a second panel (520), a first plate (524) and a second plate (528). The first panel (516) is a curved structure that forms the curvature of the second module (208) of the apparatus (100). The second panel (520) is approximately an L shaped panel that is positioned exactly adjacent to the existing fenestration (86). In accordance with the present invention, the first panel (516) is connected to the second panel (520) by a plurality of screws. Further, the first plate (524) is a top plate that rests above the cross-flow fan (304) and below the first closure (504). The first plate (524) includes an aperture (525) that allows the top portion of the cross-flow fan (304) to fit within the aperture (525). The radius of the aperture (525) is approximately equal to the radius of the top of the cross-flow fan (304). Further, the second plate (528) is a bottom plate that is positioned between the first unit (228) and the third unit (236). The second plate (528) includes a second aperture (526) that allows the bottom portion of the cross-flow fan (304) to fit within the aperture (526). The radius of the aperture (526) is approximately the same as that of the cross-flow fan (304). The motor (404) of the apparatus (100) is positioned below the second plate (528). Further, the connector (416) is positioned between the first plate (524) and the top closure (504). The connector (416) is positioned such that it supports the cross-flow fan (304) and aids free rotation of the cross-flow fan (304).
Further, the second unit (232) includes a third panel (532), a fourth panel (536), a third plate (540) and a fourth plate (544). The third panel (532) is a curved structure that forms the curvature of the second module (208) of the apparatus (100). The fourth panel (536) is approximately an L shaped panel that is positioned exactly adjacent to the existing fenestration (86). In accordance with the present invention, the third panel (532) is connected to the fourth panel (536) by a plurality of screws. The third plate (540) forms the lower end of the second unit (232). Further, the second closure (508) covers the third plate (540), sealing the apparatus for the lower end. The fourth plate (544) is a top plate of the second unit (232). The fourth plate (544) is positioned such that it forms the lower part of the third unit (236). It is noted that each of the plates (524, 528, 540, 544) has a distinctive shape such that one side is a curved side that extends from the second module (208) to the first module (204). Further, the second side of each of the plates (524, 528, 540, 544) is approximately L shaped such that it corresponds to the dimensions of the existing fenestration of the wall. The third side of the plates (524, 528, 540, 544) is straight such that together they define the side view of the apparatus (100). It is noted that the frame (220) of the first module (204) encloses the second sides of each of the plates (524, 528, 532, 536) such that the plates (524, 528, 532, 536) constitute the formation of the first slit (212) and the second slit (216).
In accordance with the present invention, the third unit (236) includes a fifth panel (548) and a sixth panel (552). The fifth panel (548) is a curved structure that forms the curvature of the second module (208) of the apparatus (100). The sixth panel (552) is approximately an L shaped panel that is positioned exactly adjacent to the existing fenestration (86). In accordance with the present invention, the fifth panel (548) is connected to the sixth panel (552) by a plurality of screws. Further, the second plate (528) defines the top of the third unit (536) and the fourth plate (544) defines the bottom of the third unit (236). In accordance with the present invention, each of the plates (524, 528, 532, 536) define a depression that allow for the plates (524, 528, 532, 536) to fit within the respective panels.

In another embodiment, the apparatus (100) includes a pair of cross flow fans. A first cross-flow fan is positioned within the first unit (228) and a second cross-flow fan is positioned within the second unit (232). The positioning of the second cross-flow fan allows for high speed of expulsion of air through the second unit (232) into the outer environment. In this embodiment, the user is able to control the rate of entry of fresh air as well as rate of expulsion of stale air from the enclosed space into the outer environment.
Referring to FIGS. 6A through 6D, the positioning and curvature of the second module (208) is described. The cross-flow fan (304) is a cylindrical structure that is positioned vertically within the first unit (228). The cross-flow fan (304) includes a plurality of blades (412) in a whorled formation, situated on an impeller (604) of the cross-flow fan (304). This whorled formation of the blades (412) allows the cross-flow fan (304) to rotate due to influx of air from the outer environment. The radius of the impeller (604) determines the effective fresh air influx into an enclosed space. For example, for a room of volume 1440 cu. ft., approximately 400 CFM of fresh air is required. Therefore, according to this an impeller (604) of preferably 47mm radius is required for optimum fresh air influx into the enclosed space.
Further, the cross-flow fan (304) is positioned within the curvature of the first unit (228) such that a pair of gaps (608, 612) are formed. The first gap (608) is the predefined gap between the blades (412) of the cross-flow fan (304) and the inner curvature of the first panel (516) of the first unit (228). The second gap (612) is the predefined gap between the second panel (520) of the first unit (228) with the blades (412) of the cross-flow fan (304). In the preferred embodiment of the present invention, each of the two gaps (608, 612) has a predefined width such that allow for high pressure influx into the input unit (228). Rotation of the cross-flow fan (304) forms a high-pressure zone in the second gap (612). The high-pressure zone directs the fresh air received from the outer environment to the only available gap for release which is the first slit (212) of the first module (204) of the apparatus (100). This high-pressure release of air into the enclosed space leads to a laminar flow of air that reached all corners of the enclosed space gradually.
In accordance with the present invention, the first gap (608) has the approximate dimensions of 8mm, whereas the second gap (612) has the approximate dimension of 4mm. Further, width of the first slit (212) is approximately 40mm. Also, the cavities on the second module (208) of the first unit (228) are approximately 120mm in width.
The cross-flow fan (304) generates airflow which is typically a laminar air flow into the enclosed space through the first slit (212). Laminar air flow is advantageously achieved due to the positioning of the cross-flow fan (304) within the second module (208) such that two gaps (608, 612) are formed between the cross-flow fan (304) and the second module (208). It is well known in the prior art that Laminar air flow is a unidirectional, smooth airflow, that is characterized by a consistent, non-turbulent flow of air. Conventional fans such as ceiling fans lead to turbulent air flow in the room that are chaotic and irregular motion of air and are characterized by random fluctuations in velocity and direction, forming eddies and swirls. The positioning of the cross-flow fan (304) along with the curvature of the second module (208) lead to entry of a consistent velocity of fresh air into the enclosed space.
When the cross-flow fan (304) rotates, fresh air from the outer environment enters into the apparatus (100) through the membrane (308) of the first unit (228). The entry of fresh air into the first unit (228) is shown by arrows ‘A’. The rotation of the cross-flow fan (304) advantageously allows entry of fresh air into the apparatus (100). This fresh air is then pushed out of the slit (212) of the first unit (228). The exit of fresh air from the input unit (228) is shown by arrows ‘B’. This allows consistent entry of fresh air into the enclosed space for a prolonged period of time.
In accordance with the present invention, the positioning of the cross-flow fan (304) in the second module (208) of the apparatus (100) allows for minimal noise of the cross-flow fan (304) in the enclosed space. This leads to an efficient fresh air delivery system that is integrable into existing fenestration fixtures, emitting minimal noise.
Referring to FIGS. 7 and 8A, the inflow and outflow of air in the apparatus (100) is described. The cross-flow fan (304) is positioned in the first unit (228) of the apparatus (100). The cross-flow fan (304) includes an impeller (604) and a plurality of blades (412). Further, the cross-flow fan (304) is engaged with the motor (404) that is positioned in the third unit (236). The blades (412) are arranged around the impeller (604) in a whorled formation such that the concave part of the blades (412) is inward. This allows the cross-flow fan (304) to receive air, rotate and push air in another direction.
Now, the inflow and outflow of air in the apparatus (100) is described. In a first step, as air flows in the outer environment, the cross-flow fan (304) rotates through the actuation from the motor (404). In a next step, rotation of the cross-flow fan (304) leads to entry of air into the first unit (228) of the apparatus (100). The entry of fresh air into the first unit (228) is depicted by arrows ‘C’. In a next step, air pressure builds up within the second gap (612) of the first unit (228) due to influx of fresh air along with rotation. The rotation of the cross-flow fan (304) creates a single exit for the pressure in the pressure zone. In a next step, pressurized fresh air exits the input unit (228) into the enclosed space through the first slit (212). The exit of fresh air into the first unit (228) is depicted by arrows ‘D’. In a next step, constant exit of pressurized air into the enclosed space leads to laminar air flow within the enclosed space. In a next step, gradual influx of laminar air flow of fresh air leads to pre-existing stale air to move to the lower end of the enclosed space. In a next step, stale air then exits the enclosed space through the second slit (216) of the first module (204) of the apparatus (100). The entry of stale air into the second slit (216) is depicted by arrow ‘E’. In a next step, stale air moves through the second unit (232) to the outer environment. The exit of stale air from the second unit (232) into the outer environment is depicted by arrow ‘F’. In a final step, the circulation of fresh air into the room from the first slit (212) and expulsion of stale air through the second slit (216) continues till the user turns off the apparatus (100). The rate of transfer of fresh air and stale air depends upon the speed of air currents in the outer environments.
In the preferred embodiment of the present invention, the cross-flow fan (304) is preferably made of plastic. However, a person skilled in the art will appreciate that the cross-flow fan (304) may be made of any other material as per the user’s requirement. The rate of change of air is provided through the number of air changes per hour (ACH). The air changes per hour is a measure of the volume of air supplied to or extracted from a space such as a room over time. When the air within a space is assumed to be uniform, the ACH indicates the number of times the total volume of air in the defined space is replaced in an hour. The amount of fresh air required in a room is then calculated by the following formula:
Q = nV
Where, Q = Fresh air supply or air exchange required;
n = air exchange rate required per hour
V = Volume of the space.
Now, a process for calculating requirement of the minimum amount of fresh air supply in a room is described. In a first step, the minimum air exchange required in a room is considered to be 4 as per norms of the National Building Code of India (NBC). In a second step, volume of the room is calculated. The volume of a room with dimensions 12’ x 12’ x 10’ is 1440 cu. ft. In a next step, the amount of fresh air supply required is calculated through the formula Q = nV.
Q = nV
Q = 4 X 1440
Q = 5760 CFH
Q (CFM) = Q (CFH) / 60
Q (CFM) = 5760 / 60
Q (CFM) = 96
Where, CFH = Cubic Feet per Hour,
CFM = Cubic Feet per Minute.
Therefore, the minimum Fresh Air Supply required in a standard sized room is 96 CFM.
Now, a process for calculating requirement of the minimum amount of fresh air supply for night cooling in a room is described. In a first step, the minimum air exchange required in a room during the is considered to be within a range of 12 to 18 as per norms of the National Building Code of India (NBC). In a second step, volume of the room is calculated. The volume of a room with dimensions 12’ x 12’ x 10’ is 1440 cu.ft. In a next step, the amount of fresh air supply required at night for night cooling is calculated through the formula Q = nV.
Q = nV
Q = 16 X 1440
Q = 23040 CFH
Q (CFM) = Q (CFH) / 60
Q (CFM) = 23040 / 60
Q (CFM) = 384
Where, CFH = Cubic Feet per Hour,
CFM = Cubic Feet per Minute.
Therefore, the minimum Fresh Air Supply required during night time for night cooling in a standard sized room is 384 CFM.
Now referring to FIG. 1 to 8B, the operation of the apparatus (100) of the present invention is described. In a first step (804), the user turns on the apparatus (100) through the display regulator (432) positioned on the apparatus (100). In a next step (808), the user inputs into the display regulator (432) any required parameters such as speed of the fan blades, temperature, humidity and the like. In a next step (812), the controller (424) in the third unit (236) is activated. The controller (424) then initiates the motor (404) that is situated in the third unit (236) that in turn commences rotation of the cross-flow fan (304) as per the speed parameters set by the user initially. In a next step (816), fresh air enters into the apparatus (100) due to rotation of the cross-flow fan (304). In a next step (820), the rotation of the cross-flow fan (304) creates high pressure in the second gap (612) in the first unit (228) and pushes the fresh air from the outer environment into the enclosed space. In a next step (824), as fresh air is pushed into the enclosed space and stale air from the enclosed space is pushed out through the second unit (232). The empty duct of the second unit (232) ensures efficient overhaul of the stale air into the outer environment. In a next step (828), the input of fresh air into the enclosed space continues till the user turns off the apparatus (100). The continuous exchange of fresh air and stale air in the enclosed space, in turn circulates air within the enclosed space while simultaneously reducing the temperature within the enclosed space to reach a temperature equilibrium with the temperature in the outer environment.
Referring to FIG. 9A, experimental data with respect to the temperature within an enclosed space in presence of the apparatus (100) during night time is described. FIG. 9A is a heat map that analyses temperature patterns to optimize the system. It is evident from the heat map that the highest temperature within the enclosed space with the apparatus (100) is right next to the two slits (212, 216). Further, the least temperature within the enclosed space is farthest from the apparatus (100). It is common general knowledge that the outer environment is cooler by 1 to 2 degrees celsius as compared to a completely enclosed space in tropical regions such as India. In such a situation, it is evident from the FIG. 9A that cooler, fresh air enters into the enclosed space through the upper first slit (212) and comparatively hot, stale air exits from the enclosed space, through the second slit (216) of the apparatus (100).
Referring to FIG. 9B, laminar air flow within an enclosed space in presence of the apparatus (100) is depicted. It is evident from the wind pattern map that a path of the air entering into the enclosed space is a circular path. As fresh air enters into the enclosed space through the first slit (212), it gets thrown ahead, in a forward direction due to high pressure within the first unit (228) of the apparatus (100). The throw of fresh air allows the fresh air to reach the farthest point of the enclosed space. It is also noted that the flow of fresh air is controlled and this controlled flow pattern prevents ‘short circuiting’ of air. ‘Short circuiting of air’ refers to immediate expulsion of fresh air inadvertently. Instead, the apparatus (100) maintains a deliberate, directional movement of fresh air that ensures efficient ventilation and thermal regulation.
In another embodiment of the present invention, two or more apparatus (200) are stackable onto each other when the height of the fenestration is larger or requirements of fresh air of an enclosed space are not met by a single apparatus (200). Further, in other embodiment, the apparatus (300) is integrable on any side of a fenestration such as top, bottom, or the sides as per the user’s requirements. In yet another embodiment, two or more apparatus (100) are integrable on the same fenestration depending upon the fresh air requirement of the enclosed space. It is noted that the apparatus (100) is integrably positionable in any manner onto one or more fenestrations are per the requirement of fresh air as anticipated by a person skilled in the art.
In another embodiment of the present invention, the fenestration integrated fresh air ventilation apparatus (100) is further configured with pollution-control features to ensure that the air introduced into an enclosed space (80) is not only fresh but also clean and safe. This embodiment is particularly advantageous in urban or industrial regions where outdoor air is heavily contaminated with particulate matter, gaseous pollutants, and volatile organic compounds (VOCs). It is understood, however, that the conventional ventilation systems in such environments merely facilitate air exchange without addressing pollution, thereby introducing harmful pollutants into the enclosed space. This embodiment overcomes these limitations by incorporating multi-stage filtration, a comprehensive sensor network, and adaptive control logic that regulates operation based on both indoor and outdoor air quality parameters.
According to this one embodiment, the apparatus (100) retains the general structure of the first embodiment, wherein the first module (204) is mounted on the interior side of a fenestration (84) and the second module (208) is mounted on the exterior side of the fenestration. The first module (204) continues to include a frame (220) with a first slit (212) for the entry of fresh air and a second slit (216) for the discharge of stale air. The second module (208) similarly includes the intake unit (228), the exhaust unit (232), and the central unit (236) which houses the motor (404), controller (744), and circuitry (428). However, in this embodiment, the intake unit (228) includes a multi-stage filtration assembly (702) that is arranged in sequence to progressively remove pollutants from incoming outdoor air.
The filtration assembly includes a coarse pre-filter that captures larger particles, insects, and dust. Downstream of the pre-filter, a high-efficiency particulate filter, such as a HEPA-grade filter, is positioned to remove fine particulate matter, specifically PM2.5 and PM10, which are known to penetrate deep into human lungs and cause respiratory illnesses. Following this stage, an activated carbon filter is provided to adsorb odours, volatile organic compounds, and gaseous pollutants such as nitrogen oxides, sulphur dioxide, and ozone. In some configurations, the activated carbon filter is further enhanced by impregnated chemicals for selective removal of toxic gases. Optionally, a photocatalytic filter coated with titanium dioxide is integrated along with ultraviolet-C (UV-C) light emitting diodes (732). In accordance with the present invention, this stage decomposes nitrogen oxides, VOCs, and harmful organic vapours through catalytic oxidation, thereby providing an additional layer of purification. The filters are mounted in a removable cartridge format to enable easy servicing and replacement by the user without requiring specialized tools.
In addition to filtration, this embodiment introduces a comprehensive sensor array that monitors both indoor and outdoor environments. A plurality of sensors (740) are disposed within the intake unit (228) and the central unit (236). Examples of such sensors include particulate matter sensors of the optical laser scattering type configured to measure PM2.5 and PM10 concentrations. Gas sensors of the electrochemical or metal-oxide semiconductor type are included for detecting nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O3), carbon monoxide (CO), and similar pollutants.
A non-dispersive infrared (NDIR) sensor is included for monitoring carbon dioxide concentration within the enclosed space. Further, volatile organic compound sensors are provided to detect substances such as formaldehyde, benzene, and other hazardous compounds released from building materials or furnishings. Temperature sensors, including resistance temperature detectors (RTDs) or thermistors, and humidity sensors, such as capacitive or resistive sensors, are also incorporated. Additionally, pressure sensors and airflow sensors of MEMS-based design are included to measure differential pressure across the filter media and confirm that air passes through the filters without bypass.
The integration of this sensor network with the controller (744) enables adaptive logic for real-time decision making. The controller continuously compares indoor and outdoor air quality index (AQI) values. When outdoor air is cleaner than indoor air, the controller increases the intake airflow to maximize ventilation. Conversely, when outdoor air is more polluted, the controller reduces the intake rate, shifts the system into filtration-dominant mode, or, in severe cases, temporarily suspends outdoor intake to prevent pollutant ingress.
In accordance with present invention, the logic also includes an override feature based on carbon dioxide levels: if the indoor carbon dioxide concentration rises above 1000 ppm, the controller temporarily increases ventilation regardless of outdoor pollution levels, ensuring that oxygen levels are replenished. When particulate matter levels outdoors exceed 150 µg/m³, the controller reduces the intake airflow to a minimum threshold, activates all filtration stages, and alerts the user through the display regulator (432). In case of sudden spikes in VOCs, such as formaldehyde above 0.6 ppm, the system prioritizes the activated carbon stage, increases fan speed, and notifies the user via both the on-device display and the wireless application (756). Furthermore, if dangerous gases such as NO2, SO2, or O3 exceed permissible safety thresholds, the controller can switch the apparatus into a protective recirculation mode, pausing outdoor intake until levels normalize.
The display regulator (432) in this embodiment presents a detailed interface for the user. It displays particulate levels (PM2.5 and PM10), carbon dioxide concentration, VOC levels, humidity, and temperature in real-time. These values are accompanied by a color-coded AQI indicator ranging from green (good) to yellow (moderate) to red (hazardous). The user has option to adjust fan speeds manually if desired, but the default mode is adaptive automation managed by the controller. The apparatus (100) also includes wireless connectivity such as Wi-Fi or Bluetooth Low Energy (BLE), enabling integration with a mobile application (756). The mobile application performs continuous monitoring, historical trend analysis, remote control of the apparatus, scheduling of operation cycles, and even cloud-based diagnostics.
During operation in polluted environments, the apparatus demonstrates intelligent behavior. For example, when outdoor air quality index is 200 with PM2.5 concentration at 180 µg/m³, while indoor AQI is 90, the controller reduces intake airflow, maintains a minimal 40 cubic feet per minute (CFM) to keep carbon dioxide under 800 ppm, and activates the HEPA and carbon filters. In another case, when indoor carbon dioxide rises above 1200 ppm despite poor outdoor AQI, the controller overrides its pollution-protection mode, temporarily increases ventilation to dilute carbon dioxide, and then reverts to filtration-dominant mode. In yet another case, a sudden spike of volatile organic compounds is detected indoors at 0.7 ppm formaldehyde.
The controller responds by increasing fan speed to medium, activating the carbon filter stage, and displaying a “VOC Alert” on the regulator while simultaneously sending a push notification to the mobile application. This embodiment provides several advantages. It ensures pollution-resilient ventilation by combining active monitoring with dynamic adjustment of intake and filtration. It achieves a balance between adequate oxygenation and minimization of pollutant ingress. It provides user safety through alerts and automated responses while allowing manual intervention when desired. The inclusion of AQI-based control, carbon dioxide override, VOC management, and gas safety switching represents a significant advancement over prior systems. Furthermore, the apparatus maintains its integrability within existing fenestration frames and continues to appear concealed, with only the narrow visible slits (212, 216) apparent to the user. Maintenance is simplified through tool-free filter replacement and a removable cover plate (312) for servicing the motor, controller, and sensors.
By integrating filtration, sensing, and logic into a compact fenestration-mounted unit, this embodiment extends the utility of the apparatus (100) beyond mere ventilation to become a comprehensive indoor air quality management system. It adapts intelligently to environmental conditions and user needs, thereby ensuring comfort, safety, and energy efficiency in enclosed spaces located even in highly polluted urban settings.

EXAMPLES:
Only a few examples and implementations are disclosed. Variations, modifications, and enhancements to the described examples and other implementations can be made based on what is disclosed.
Examples are set forth herein below and are illustrative of different amounts and types of reactants and reaction conditions that can be utilized in practicing the disclosure. It will be apparent, however, that the disclosure can be practiced with other amounts and types of reactants and reaction conditions than those used in the examples, and the resulting device’s various different properties and used in accordance with the disclosure above and as pointed out hereinafter.
Example 1:
When the apparatus (100) of the present invention is positioned in an enclosed space of dimensions 12’ x 12’ x 10’, the volume of the enclosed space is 1440 cu. ft. Using the Q = nV formula, it is known that the fresh air requirement of this enclosed space is 384 CFM. During summers, during night time, the temperature in the outer was reduced to approximately 21 ?, whereas, the indoor temperature was at approximately 25 ?. When the apparatus (100) was activated, it was observed that the exchange of fresh air and stale air led to reduction in temperatures in the enclosed space.
Time recorded from activation of apparatus (100) Temperature recorded from activation of apparatus (100)
10 minutes 26.5 ?
20 minutes 24.2 ?
40 minutes 23.2 ?
60 minutes 21.5 ?
Table 1: Table depicting recorded reduction in temperature.
Table 1 describes the gradual reduction in temperature observed after activating the apparatus (100) of the present invention. It is evident that once activated, the apparatus (100) brings the temperature within the enclosed space to an equilibrium with the outer environment within approximately 1 hour time. Further, if the user sets the temperature parameters on the display regulator (428), the apparatus (100) shall reach the specified temperature through increasing or decreasing the fan speed. It is further evident that the apparatus (100) provides constant fresh air throughout the night, maintaining the temperature as per the outer environment, thereby eliminating the need for any conventional cooling systems such as fans, air conditioners or the like.

The apparatus (100) advantageously allows natural ventilation of air into enclosed spaces that do not have cross-ventilation facility. The apparatus (100) advantageously senses and monitors the air parameters such as temperature and air quality of the enclosed space. Further, the apparatus (100) is advantageously integrated within standard fenestrations and is installable in all types of enclosed spaces. Further, only a vertical slit of the apparatus (100) is advantageously visible from the inside of the enclosed space. It is also noted that when used during nighttime, the apparatus (100) advantageously cools the enclosed space or room and reduces the temperature of the room due to higher air flow exchange, thereby reducing and at times eliminating the need for air conditioners at night.
The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others, skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated.
It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the scope of the present invention.
,CLAIMS:We Claim:
1. A fenestration integrated fresh air ventilation apparatus (100) for an enclosed space (80), comprising:
a first module (204) mountable at an interior side of a fenestration (84) and including a frame (220) with at least a first slit (212) for supplying outdoor air to the enclosed space and at least a second slit (216) for discharging indoor air;
a second module (208) mountable at an exterior side of the fenestration and including a first unit (228) aligned with the first slit (212), second unit (232) aligned with the second slit (216), and a third unit (236) housing a motor (404), a controller (424), and an electric circuit (428);
the second module (208) including a curvature, the curvature being an arch of a curvature of an angle depending upon the radius of a cross-flow fan (304) enclosed in the first unit (228), enabling laminar airflow within the enclosed space;
the cross-flow fan (304) disposed in the first unit (228) and driven by the motor (404) to draw outdoor air through the first unit (228) into the enclosed space; and
a membrane (308) positioned at the first unit (228) to permit passage of air while restricting entry of particulate matter;
wherein the apparatus (100) being configured to simultaneously introduce outdoor air into the enclosed space and expel indoor air to the external environment, thereby achieving equilibrium with the air temperature in the outer environment while being integrable into a conventional fenestration frame (86).
2. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the cross-flow fan (304) being positioned within the first unit (228) forming high pressure zones and allowing single exit for fresh air through the first slit (212), thereby generating a laminar air flow throughout the enclosed space.
3. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the apparatus (100) being a modular apparatus such that the apparatus (100) is integrable onto any size of fenestration.
4. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the first module (204) presenting only a visible frame (220) with the first slit (212) and second slit (216) when installed, the remainder being concealed within any side of the fenestration.
5. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the plurality of sensors (740) including at least one sensor selected from:
(a) a particulate matter sensor configured to detect PM2.5 and PM10;
(b) a non-dispersive infrared sensor configured to measure carbon dioxide;
(c) an electrochemical gas sensor configured to detect nitrogen dioxide, sulfur dioxide, ozone or carbon monoxide; and
(d) a volatile organic compound sensor.
6. The fenestration integrated air ventilation apparatus (100) as claimed in claim 1, wherein the width of the second module (208) being approximately 135 mm.
7. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the width of the first module (204) being approximately between 75 mm and 120 mm.
8. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the width of the first gap (608) being approximately 8 mm and the width of the second gap (612) being approximately 4 mm leading to a pressure zone for fresh air being formed within the gaps (608, 612), thereby leading to the laminar air flow within the enclosed space.
9. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the intake unit (228) including a multi-stage filtration assembly including a pre-filter, a particulate filter configured to capture particles of size less than 2.5 microns, and an activated carbon filter for adsorption of volatile organic compounds and gaseous pollutants.
10. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein a plurality of apparatus (100) being stackable onto each other to modularly integrate multiple apparatus (100) into a single fenestration.
11. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the membrane (308) being a semi-permeable membrane that allows entry of fresh air into the apparatus (100) without any of the particulate matter present in the outer environment.
12. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the cross-flow fan (304) being suspended by a connector (416) and pivot bearing (420) to reduce vibration and noise.
13. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the sensors (436) sensing at least one parameter selected from temperature, humidity, wind speed, carbon dioxide concentration, particulate concentration or volatile organic compounds.
14. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the controller (424) automatically adjusting fan speed based on sensor inputs to achieve a predetermined air-exchange rate.
15. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, including a display regulator (432) operable from the interior of the enclosed space to display sensed parameters and allow manual adjustment of fan speed.
16. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the controller (744) being configured to compare indoor and outdoor air quality indices and regulate the cross-flow fan (304) such that outdoor intake is reduced when the outdoor AQI is poorer than the indoor AQI.
17. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the apparatus (100) including tool-free access via a removable cover plate (312) for servicing the motor (404), controller (424), or filter (308).
18. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, having wireless connectivity for remote control, scheduling, and diagnostics and wherein the controller (744) overriding pollution-control logic and increases ventilation when indoor carbon dioxide concentration exceeds 1000 ppm.
19. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, being dimensioned to achieve a minimum of four air changes per hour in a standard room volume in accordance with building code requirements.
20. The fenestration integrated fresh air ventilation apparatus (100) as claimed in claim 1, wherein the cross-flow fan (304) and first unit (228) are configured to produce an airflow rate of at least 96 cubic feet per minute (CFM) in a standard room.
21. A method of ventilating an enclosed space (80) using the apparatus (100) of claim 1, comprising:
activating the controller (424) by receiving user input or sensor input;
driving the motor (404) to rotate the cross-flow fan (304);
drawing outdoor air through the membrane (308) of the first unit (228) into the enclosed space via the first slit (212);
discharging indoor air from the enclosed space through the second slit (216) to the second unit (232); and
repeating the above steps to maintain continuous air exchange.

Dated this 26th day of September 2024.
For, AHOU VENTURES LLP,

Mahurkar Anand Gopalkrishna
IN/PA-1862
(Agent for Applicant)