Refrigeration – With illuminating or radiant energy means
Reexamination Certificate
1999-07-16
2001-02-06
Doerrler, William (Department: 3744)
Refrigeration
With illuminating or radiant energy means
C062S078000, C062S317000
Reexamination Certificate
active
06182461
ABSTRACT:
This invention relates generally to air conditioning systems and, more particularly, to an air conditioning system having means to treat the air for microbial contaminants.
BACKGROUND OF THE INVENTION
The term “dirty socks syndrome” refers to the offensive smell that can emanate from a poorly maintained air conditioning system in which mold and/or bacteria grow on the indoor coil or in the drain pan. In addition to the undesirable smell, this microbial growth may cause the release of spores and toxins into the air so as to cause allergy related problems. Further, the buildup of mold tends to create maintenance problems because of the dirty coils, an increase in pressure drop, loss of heat exchange efficiency and possibly dirty and plugged drain pans.
Microbial growth can be temporarily treated by using chemicals such as bleach and the like. However, many of the most aggressive cleaning solutions, such as those which are chlorine based, have been banned from use in air conditioning systems. But even where approved biocidal agents are used on coils and drain pans, they do not provide a permanent solution.
The use of UV germicidal lamps have been found to be effective in controlling the growth of microbes in air conditioning systems. One of the most effective ways is to direct the light onto the coil and the drain pan so as to attack the growth directly. One example of such a system is shown in U.S. Pat. No. 5,755,103. There are also systems which filter the impurities from the air and the direct ultraviolet light onto the filter to neutralize the impurities such as are shown in U.S. Pat. Nos. 5,879,435 and 5,891,399. In addition, there is some systems which use the UV light to attack the growth indirectly by the use of a reactor structure which directs the light source on the air flow so as to provide a fly-by control of airborne contaminants. Examples of such systems are shown in U.S. Pat. No. 5,833,740 and U.S. Pat. No. 5,902,552.
More recently, it has been found that the effectiveness of UV irradiation in the conversion of contaminants can be substantially enhanced by the use of a catalyst, such as TiO
2
, in the reactor environment. U.S. Pat. Nos. 5,835,840; 5,790,934 and 5,865,959 show examples of such systems. It should be mentioned that, while these systems have been shown to be effective in the control of microbial growth, they are relatively expensive to implement since they require a dedicated reactor structure in order to accommodate that single function.
It is therefore an object of the present invention to provide an improved method and apparatus for the treatment of air.
Another object of the present invention is the provision for reducing microbial growth in an air conditioning system.
Yet another object of the present invention is the provision in an air conditioning system for the effective treatment of microbial growth without substantial investment.
Still another object of the present invention is the provision for an air conditioning system, which is capable of treating microbial growth, and which is economical to manufacture and effective in use.
These objects and other advantages become more readily apparent upon reference to the following description when taken in conjunction with the appended drawings.
SUMMARY OF THE INVENTION
Briefly, in accordance with one aspect of the invention, a photocatalytic agent is applied directly to the surface of the fins of the indoor heat exchanger of an air conditioning system, and the fins are irradiated with a UV light source having a wave length which is capable of activating the photocatalyst. The air passing through the evaporator then comes in contact with the photocatalyst and is purified by the activated photocatalyst. In this way, the photocatalyst process is used to simultaneously treat the surface of the heat exchanger and the air passing therethrough.
By another aspect of the invention, the UV light sources are so located that they irradiate both the evaporator coil and drain pan for purposes of directly attacking microbial growth, but also they simultaneously irradiate the coated surfaces of the evaporator coil fin surface such that the contaminated air passing therethrough is also treated.
By yet another aspect of the invention, the evaporator coil fin material is coated with a photocatalyst such as titanium dioxide, either in a pre-coating process wherein the fin is coated prior to being inserted into the heat exchanger structure or in a post-coat process wherein it is coated after it has been assembled into a heat exchanger device.
In the drawings as hereinafter described, a preferred embodiment is depicted. However, various other modifications and alternate constructions can be made thereto without departing from the true spirit and scope of the invention.
REFERENCES:
patent: 4990313 (1991-02-01), Pacosz
patent: 5501084 (1996-03-01), Chang et al.
patent: 5626020 (1997-05-01), Sangster et al.
patent: 5755103 (1998-05-01), Na et al.
patent: 5790934 (1998-08-01), Say et al.
patent: 5817276 (1998-10-01), Fencl et al.
patent: 5833740 (1998-11-01), Brais
patent: 5835840 (1998-11-01), Goswami
patent: 5865959 (1999-02-01), Meinzer et al.
patent: 5879435 (1999-03-01), Satyapal et al.
patent: 5891399 (1999-04-01), Owesen
patent: 5902552 (1999-05-01), Brickley
patent: 5911742 (1999-06-01), Akazawa
patent: 6108476 (2000-08-01), Iimura
Herbeck Christian C.
Roberts Timothy J.
Washburn Norman A.
Carrier Corporation
Doerrler William
Shulman Mark
LandOfFree
Photocatalytic oxidation enhanced evaporator coil surface... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Photocatalytic oxidation enhanced evaporator coil surface..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photocatalytic oxidation enhanced evaporator coil surface... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2591947