WO2010001381A1

WO2010001381A1 - Air quality monitor

Info

Publication number: WO2010001381A1
Application number: PCT/IL2009/000583
Authority: WO
Inventors: Gadi Porat
Original assignee: Association For Public Health Services
Priority date: 2008-06-30
Filing date: 2009-06-14
Publication date: 2010-01-07

Abstract

An air quality monitoring device for monitoring a stream of gas passing through a conduit and exiting at a gas outlet. The device comprises a flow-through element having an inlet aperture and an outlet aperture for gas to be monitored, the flow-through element further having a viewing window. The device also includes a gas quality element mounted within the flow-through element within viewing range of the viewing window. The gas quality element is adapted to change color in accordance with a change in the gas quality of the gas being monitored. Additionally, the device comprises one or more attachment members for mounting the flow-through element onto a portion of the gas outlet in a position so that the gas quality element is viewable to a viewer. The device may be used in air conditioner or other ventilation systems.

Description

AIR QUALITY MONITOR

FIELD OF THE INVENTION

The present invention relates in general to a visual monitoring device for determining air quality, including monitoring the quality of the air flowing out of a discharge vent of an air conditioner.

BACKGROUND OF THE INVENTION

Room and vehicle air conditioners (A/C) provide an effective means for cooling or heating air in a limited space. In both types of air conditioners air filtration is used to provide a cleaner and healthier environment in the house or automobile. It should be remembered that while air pollution today is bad it is expected to worsen in coming decades.

In room air conditioners, an air filter may be positioned inside a window-mounted air conditioner housing directly behind the air inlet duct. The air which is drawn into the air inlet by the air conditioner's internal fan first passes through the filter element, and then through a heat exchange coil to be cooled or heated before exiting into the room.

It is important that the air filter is changed or cleaned regularly because after a period of time the filter becomes at least partially clogged with trapped particles. When the filter becomes clogged, it reduces the flow of air into the unit, thereby reducing the effectiveness of the air conditioner. This reduction in effectiveness can be evidenced by a reduction in air flow, an increase in pollutants and/or an indication of air bypassing the filter.

Automobiles are also fitted with air conditioners. As in home air conditioners, vehicle air conditioners are designed to force outdoor air into the vehicle. In doing so, the indoor air of the vehicle is circulated by a fan and subjected to heat exchange, thereby cooling or heating the air.

A filter can also be used to prevent solid particulate pollutants (and sometimes also gaseous pollutants) from entering the inside of the vehicle. In doing so, the vehicle's air conditioner is generally provided with a filter, typically mounted between a blower unit and an air discharge passage. The typical filter is configured as a cartridge which can be easily replaced. However, a drawback exists. The driver has difficulty in determining whether or not the filter is contaminated, that is, at least partially clogged.

It is therefore desirable to provide some method of indicating that an air filter is clogged or otherwise not operating normally and requires replacing or cleaning in both room and vehicle air conditioners. Monitoring of filters in home air conditioners has been suggested. A room air conditioner filter condition indicator has been suggested where the indicator has a float inside a transparent tube on the front of the housing. When the filter is clogged the float is visible through a cutout window in the control knob and indicates that the filter requires replacing or cleaning. Another approach for monitoring an A/C filter requires providing the filter with an optical sensor. When the filter becomes contaminated with pollutants, an optical sensor causes a light receiving element to activate a warning lamp. In another approach, when the filter becomes accumulated with pollutants, a pressure differential is generated across the filter which causes a light source to be displayed indicating that the filter needs checking. Another design is constructed so that when the filter is contaminated with pollutants, an intake air pressure differential is generated across the filter, and a conductive thin film fluctuates to activate a warning light.

These conventional prior art approaches have drawbacks in that they generally have a relatively complicated construction. As a result, the cost of the parts in prior art systems, the number of parts involved in such systems, and the amount of modification to the air conditioner housing required to install a particular system is significantly greater than desirable. A simpler, less costly, system is necessary.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an air quality monitor which is simple to construct and inexpensive.

It is an object of the present invention to provide an air conditioner filter monitor/indicator which is simple to construct requiring no complex parts or electronics.

In one aspect of the present invention there is provided a device for monitoring a stream of gas passing through a conduit and exiting at a gas outlet. The device includes a flow-through element having an inlet aperture and an outlet aperture for gas to be monitored, the flow-through element further having a viewing window. It also includes a gas quality element mounted within the flow-through element within viewing range of the viewing window, and the gas quality element is adapted to change color in accordance with a change in the quality of the gas being monitored. The device further includes one or more attachment members for mounting the flow-through element onto a portion of the gas outlet in a position so that the gas quality element is viewable to a viewer. In one embodiment of the device, the one or more attachment members are formed as one or more clip-on attachment members. In some instances of this embodiment, the one or more clip-on attachment members are removably attachable to movable slats positioned over the gas outlet of the conduit. The one or more clip-on attachment members when attached to the slats do not affect the movability of the slats.

In yet another embodiment of the device, the one or more attachment members are adapted to be mounted on slats positioned over the gas outlet of an air conditioner.

In still another embodiment of the device, the outlet aperture of the flow-through element is positioned within the viewing window. In another embodiment of the device, the inlet aperture of the flow-through element is two or more inlet apertures.

In still another embodiment of the device, the outlet aperture of the flow-through element is two or more outlet apertures.

In a further embodiment of the device, the gas quality element is comprised of absorbent material. In some instances of this embodiment, the absorbent material is formed of open cell foam.

In yet another embodiment of the device, the gas quality element is comprised of filter material. In some instances, the filter material is filter paper. In some instances, the filter paper is formed of different areas, each area having different pore sizes and pore densities.

In another embodiment of the device, the gas quality element includes adhesive material. In some instances of this embodiment, the gas quality element is further comprised of absorbent material.

In yet another embodiment of the device, the gas quality element is a chemical indicator for indicating the acidity of the air emitted from the gas outlet of the conduit. In some instances of this embodiment, the gas quality element further includes an absorbent or adhesive material. In still another embodiment of the device, the device is mountable onto a portion of the gas outlet of the conduit and the conduit is part of a vehicular air conditioner, a home air conditioner, or a central air conditioning system.

In yet another embodiment of the device, the device is adapted for a single temporary use.

In a further embodiment of the device, the viewing window is removably positioned on the flow-through element and the gas quality element may be replaced by removing the window without removing the device from the gas outlet.

In a further embodiment of the device, the flow-through element is further comprised of walls and the viewing window is positionable on the walls. A gas quality element support member is spaced apart from the viewing window, and the viewing window and the gas quality element support member form a flow-through space. Air from the gas outlet enters the inlet aperture of the flow-through element, flows through the flow-through space over the gas quality element and exits from the outlet aperture which is positioned in the viewing window.

In another aspect of the present invention, there is provided a device adaptable for removable positioning on the louvers of a gas outlet of a conduit. The conduit is an exhaust of an air conditioner and the device monitors the quality of the gas exiting the gas outlet. The device includes walls having one or more attachment members extending substantially transversally therefrom. It also includes a gas quality element support member having a first and a second face and having one or more apertures formed therein. The support member is attached to and connects the walls. The device also includes one or more gas quality elements affixed to the first face of the gas quality element support member. The first face is positioned distal from the gas outlet of the conduit. The device is configured to cause air emitted from the gas outlet of the conduit to flow through the one or more apertures of the gas quality element support member and over the one or more gas quality elements. Visual inspection by a viewer of color changes in the one or more gas quality elements readily indicates when a filter of the air conditioner requires replacement or cleaning. In another embodiment of this device, the device further includes a viewing window having one or more apertures formed therein. The window is positionable on the walls of the device and spaced apart from the gas quality element support member. The viewing window and the gas quality element support member form a flow-through space where air from the gas outlet enters the one or more apertures of the gas quality element support member, flows through the flow-through space and over the one or more gas quality elements exiting from the one or more apertures in the viewing window.

In still another embodiment of this device, the one or more attachment members are configured as clip-on attachment members for attachment to the louvers of the air conditioner.

In a further embodiment of this device, the one or more gas quality elements are selected from one or more materials in the following group of materials, the group consisting of: an absorbent material; a filter material; an adhesive material; and a chemical indicator material.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention.

In this regard, no attempt is made to show structural details of the invention in greater detail than is necessary for a fundamental understanding of the invention. The description taken with the drawings make apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

In the drawings:

Figs. 1A, 1 B and 1C provide a schematic side cut-away view, a schematic side view and a schematic top view, respectively, of a device constructed according to an embodiment of the present invention; and

Fig. 2 shows a device constructed as shown in Figs. 1A-1C positioned on a slat over a discharge vent of an air conditioner. Similar elements in the Figures are numbered with similar reference numerals.

DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides a removably attachable air conditioner filter monitor adapted to sit on or between the louvers in the discharge vent of an air conditioner or other ventilation system. The monitor is held directly in front of the flow of air emerging from the discharge vent trapping particulate or pollutant gas discharges therefrom. The monitor monitors and provides an indication of the degree of clogging or improper positioning or otherwise non-normal operation of the air conditioner's or ventilation system's filter. The monitor may itself be constructed so as to direct the air flow over its gas quality element; this element may also be denoted herein as an indicator material element. The gas quality element/indicator material element is readily visually observable and is used to determine when replacement or cleaning of the air conditioner's or ventilation system's filter is required.

The device described herein is adaptable for general gas quality monitoring. It allows for monitoring a stream of gas passing through a conduit and exiting a gas outlet. The device comprises a flow-through element, the element having a gas inlet aperture and a gas outlet aperture. There is a viewing window attached to, or positioned on, the flow-through element. The device includes a gas quality element mounted within the flow- through element and within viewing range of the viewing window. The gas quality element is adapted to change color in accordance with a worsening in the quality of the gas being monitored. The device also includes at least one attachment member for mounting the flow-through element onto a portion of, or adjacent to, the gas outlet. Mounting of the device is effected in such a way that the gas quality element is viewable to a viewer.

Reference is made to Figs. 1A, 1 B and 1C which show a side cut-away view, a side view and a top view, respectively, of the device constructed according to an embodiment of the present invention. Device 10 comprises a wall 26 and at least one pair of attachment members 12, typically, but without limiting the invention, positioned substantially transverse to wall 26. These may be formed of any semi-rigid polymeric material of suitable strength such as, but without intending to limit the invention, polypropylene, polystyrene or polycarbonate. Emerging from wall 26 is a gas quality element support member, also at times herein denoted an indicator material support member 28, formed of the same material as attachment members 12 and wall 26. There is a gas inlet aperture 18 formed at one side of gas quality element support member 28. Attachment members 12, wall 26 and gas quality element support member 28 are typically, but without being limiting, of a unitary construction. Typically, device 10 may be fabricated using conventional polymer molding technology known to those skilled in the art. Wall 26 and gas quality element support member 28 together comprise what is denoted herein as a flow-through element.

Attached to, or positioned on, wall 26 is a transparent polymeric material viewing window 14, typically but without being limiting, formed of polystyrene or polycarbonate. Formed near the periphery of viewing window 14 is a gas outlet aperture 16. Attachment of viewing window 14 to wall 26 may be effected using adhesives or ultrasonic welding or any other method known to those skilled in the art. Viewing window 14 may also be removably attachable by, for example, screw threads or a clip-on mechanism employing flanges extending from wall 26. A gas quality element that is an indicator material element, 20, is affixed to the face of gas quality element support member 28 proximal to viewing window 14. It may be attached using an adhesive material or strip 22, but other methods of attachment known to those skilled in the art may also be used. Indicator material element 20 (and adhesive material or strip 22 when present) is of such material that it absorbs or otherwise traps particulates carried in the air emitted, for example, from the discharge vent of the air conditioner. The material is typically an absorbent or a filter material such as open pore foam or filter paper. The pore size of the indicator material is chosen so as to absorb particulates of the size expected to be emitted.

As the air conditioner filter becomes more clogged and dirtier or is in general not operating normally, the absorbent, adhesive or other indicator material of the gas quality element correspondingly darkens as a result of the deposition of soot, other carbon particulates, and other dust or dust-like particles. This darkening is readily observable through viewing window 14. Alternatively, device 10 may be removed from its position on, or between, the louvers in front of the discharge vent of the air conditioner and examined. Visual follow-up of the progress of filter darkening may extend over a period of time, for example, one or two weeks.

In some embodiments, there may be an additional gas quality element comprised of adhesive or filter material on the face of gas quality element support member 28 distal from viewing window 14.

In other embodiments, outlet aperture 16 need not be positioned in viewing window 14 but rather may be positioned in wall 26 below window 14.

In some embodiments, gas quality element, that is indicator material element, 20 may be made of a chemical indicator material, such as a pH sensitive material. The pH sensitive material changes color when the air emitted from the discharge vent is acidic as a result of, for example, the presence of excessive sulfur dioxide. Such pH materials are readily available commercially.

In other embodiments, the chemical indicator material may form the gas quality element support member 28 together with a particulate foam, filter, or other adhesive or absorbent material.

As shown in Fig. 1A, in device 10, gas quality element support member 28 may be configured to form decreasing volume sections in the space between it and viewing window 14 when advancing from one side of the device to the other. This speeds up the gas flow which enters via inlet aperture 18 and exits from outlet aperture 16. Inlet aperture 18 and outlet aperture 16 are typically, but without intending to limit the invention, positioned substantially opposite each other along a diameter of device 10 (see Fig. 1C, for example).

In yet other embodiments of the invention, gas quality element support member 28 and window 14 are essentially parallel to each other and therefore the volume sections between member 28 and viewing window 14 are uniform throughout. There are no decreasing volume sections when advancing from one side of device 10 to the other. In this latter embodiment, air speed may be increased by forming inlet aperture 18 so that it is greater in size than outlet aperture 16. One of the goals in increasing air speed is to increase the flow in the region between viewing window 14 and gas quality element support member 28. This increases the rate of soot and other particulate deposition on the indicator material of gas quality element 20.

It should be understood that while wall 26 of device 10 is shown as a having a circular configuration, in other embodiments the shape of the device can be square, rectangular, ellipsoidal, polygonal, or any other shape.

Shown in Fig. 2, to which reference is now made, is a device 10 constructed according to the embodiment of the present invention discussed in conjunction with Figs. 1A-1C. Device 10 is attached to the louvers or slats 32 of an air conditioner or ventilation system. Attachment members 12 are formed to function as a clip clippable to the louvers or slats 32 by the clip's pinching action. The resilience of the material from which the attachment members are constructed allows them to slide over the louvers and be held in place thereon. In other embodiments, other attachment members may be formed to be inserted between the louvers or slats and to be held in place therebetween. The monitors of the present invention may be adapted for single temporary use and discarded after the indicator has been discolored.

In other embodiments, the indicator material member of the monitor may be replaced while the monitor is still held in position on or between the gas outlet of a conduit, for example, the louvers over the gas outlet of the air conditioning apparatus. In such instances, viewing window 14 may be removably positioned on wall 26.

The monitors of the present invention may be constructed to be used with vehicular, home or central air conditioning systems.

It should readily be understood that the monitors described herein above may be employed when the air conditioning or ventilation system is used in either the cooling or heating mode.

The discussion herein above, in the main, discusses monitoring air quality in air emitted from the discharge vent of an air conditioner or other ventilation system. It should be understood that the device described herein can be used to monitor air quality being emitted though a gas outlet from any type of conduit. It should also be noted that the terms "gas" and "air" as used herein are used such that "gas" denotes any gas or mixture thereof, including air, and "air" denotes air or any other gas or gas mixture except where contextually obvious otherwise, for example, when discussing air conditioners.

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. Therefore, it will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described herein above. Rather, the scope of the invention is defined by the claims that follow.

Claims

1. A device for monitoring a stream of gas passing through a conduit and exiting at a gas outlet, said device comprising: a flow-through element having an inlet aperture and an outlet aperture for gas to be monitored, said flow-through element further having a viewing window; a gas quality element mounted within said flow-through element within viewing range of said viewing window, wherein said gas quality element is adapted to change color in accordance with a change in the quality of the gas being monitored; and at least one attachment member for mounting said flow-through element onto a portion of the gas outlet in a position so that said gas quality element is viewable to a viewer.

2. The device according to claim 1 wherein said at least one attachment member is formed as a clip-on attachment member.

3. The device according to claim 2 wherein said at least one clip-on attachment member is removably attachable to movable slats positioned over the gas outlet of the conduit, said at least one clip-on attachment member when attached to the slats does not affect the movability of the slats.

4. The device according to claim 1 wherein said at least one attachment member is adapted to be mounted on slats positioned over the gas outlet of an air conditioner.

5. The device according to claim 1 wherein said outlet aperture of said flow- through element is positioned within said viewing window.

6. The device according to claim 1 wherein said inlet aperture of said flow-through element is at least two inlet apertures.

7. The device according to claim 1 wherein said outlet aperture of said flow- through element is at least two outlet apertures.

8. The device according to claim 1 wherein said gas quality element is comprised of absorbent material.

9. The device according to claim 8 where said absorbent material is formed of open cell foam.

10. The device according to claim 1 wherein said gas quality element is comprised of filter material.

11. The device according to claim 10 wherein said filter material is filter paper.

12. The device according to claim 11 where said filter paper is formed of different areas, each area having different pore sizes and pore densities.

13. The device according to claim 1 wherein said gas quality element includes adhesive material.

14. The device according to claim 13 wherein said gas quality element is further comprised of absorbent material.

15. The device according to claim 1 wherein said gas quality element is a chemical indicator for indicating the acidity of the air emitted from the gas outlet of the conduit.

16. The device according to claim 15 wherein said gas quality element further includes an absorbent or adhesive material.

17. The device according to claim 1 wherein said device is mountable onto a portion of the gas outlet of the conduit where the conduit is part of a vehicular air conditioner, a home air conditioner, or a central air conditioning system.

18. The device according to claim 1 wherein said device is adapted for single temporary use.

19. The device according to claim 1 wherein said viewing window is removably positioned on said flow-through element and said gas quality element may be replaced by removing said window without removing said device from the gas outlet.

20. The device monitor according to claim 1 , wherein said flow-through element is further comprised of walls and said viewing window is positionable on said walls and wherein a gas quality element support member is spaced apart from said viewing window, said viewing window and said gas quality element support member forming a flow-through space where air from the gas outlet enters said inlet aperture of said flow-through element, flows through said flow-through space over said gas quality element and exits from said outlet aperture which is positioned in said viewing window.

21. A device adaptable for removable positioning on the louvers of a gas outlet of a conduit, the conduit being an exhaust of an air conditioner, for monitoring the quality of the gas exiting the gas outlet, said device comprising: walls having at least one attachment member extending substantially transversally therefrom; a gas quality element support member having a first and a second face and having at least one aperture formed therein, said member attached to and connecting said walls; and at least one gas quality element affixed to said first face of said gas quality element support member, said first face positioned distal from the gas outlet of the conduit, wherein said device is configured to cause air emitted from the gas outlet of the conduit to flow through said at least one aperture of said gas quality element support member and over said at least one gas quality element, and wherein visual inspection by a viewer of color changes in said at least one gas quality element readily indicates when a filter of the air conditioner requires replacement or cleaning.

22. The device according to claim 21 further including a viewing window having at least one aperture formed therein, positionable on said walls of said device and spaced apart from said gas quality element support member, said viewing window and said gas quality element support member forming a flow-through space where air from the gas outlet enters said at least one aperture of said gas quality element support member, flows through said flow-through space and over said at least one gas quality element exiting said at least one aperture in said viewing window.

23. The device according to claim 21 wherein said at least one attachment member is configured as a clip-on attachment member for attachment to the louvers of the air conditioner.

24. The device according to claim 21 wherein said at least one gas quality element is selected from at least one of the following group of materials consisting of: an absorbent material; a filter material; an adhesive material; and a chemical indicator material.