US20030075047A1

US20030075047A1 - Bactericidal after-filter device

Info

Publication number: US20030075047A1
Application number: US09/982,804
Authority: US
Inventors: Normand Bolduc
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-10-22
Filing date: 2001-10-22
Publication date: 2003-04-24
Also published as: US7559968B2; CA2406900C; US20030205137A1; CA2406900A1

Abstract

A bactericidal after-filter device that mounts generally parallel to and downstream of an air filter of an air duct circulation network of a living enclosure includes a body having a front-screen element facing a back-screen element that allow for the filtered air to freely flow there through. A bactericidal medium, such as fibers forming a layer of angel's hair, is contained in between the front-screen and back-screen elements of the body and has a porosity that provides substantially no obstruction to the filtered air flowing there through while it locally retains and kills the air-suspended bacteria therein.

Description

FIELD OF THE INVENTION

The present invention relates to bactericidal devices, and more particularly to a bactericidal after-filter device for mounting parallel to and downstream of an air filter of an air duct circulation network of a living enclosure.

BACKGROUND OF THE INVENTION

Many different bacteria filter devices are presently on the market. Frequently the apparatuses for filtering bacteria are individually disposed in close proximity of the nose/mouth area of the living body.

U.S. Pat. No. 6,063,170 issued on May 16, 2000 to Deibert discloses an air filtration system having at least four interconnected chambers through which air under pressure is caused to flow. Each of the chambers contains special filter equipment adapted to remove bacteria from the air flowing therein. But, since the bacteria killing chamber is upstream of the air humidifying chamber in which bacteria/yeasts are generated because of the humidity condition, it does not catch these new bacteria/yeasts that are circulated through the air ventilation system.

This prior system is very complicated, needs to be frequently replaced after extended use due to obstruction of the filter, and would be very expensive to apply in air duct circulation networks of living enclosures such as apartments, offices, cottage houses, and the like.

A basic need exists for an efficient bactericidal device that can be used in living enclosures where people spend most of their day-to-day lives. This device should be adaptable to different air duct circulation network used for air heating and/or cooling purposes.

OBJECTS OF THE INVENTION

It is therefore a general object of the present invention to provide a bactericidal after-filter device that is adaptable to different air treatment systems for efficient and long lasting prevention against the development of bacteria and bad smells into living enclosures, including the air contained within individual portable masks.

An object of the present invention is to provide the bactericidal after-filter device that is easy to build, manufacture, maintain, clean and/or replace.

Another object of the present invention is to provide the bactericidal after-filter device that has a high level of air permeability.

A further object of the present invention is to provide the bactericidal after-filter device that continuously provides for bactericidal treatment within enclosures under conditions of frequently opened windows and/or doors such as in commercial and/or residential areas.

Other object of the present invention is to provide the bactericidal after-filter device that has intrinsic properties and that remains efficient under all types of air conditions such as humidity levels, temperature levels, etc.

Further objects and advantages of the invention will be in part obvious from an inspection of the accompanying drawings and a careful consideration of the following description.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, there is provided a bactericidal after-filter device for mounting parallel to and downstream of an air filter of an air duct circulation network of a living enclosure, the device comprises:

a body including a front-screen element facing a back-screen element for allowing filtered air to freely flow therethrough; and

a bactericidal medium contained in between said front-screen and backscreen elements of said body and having a porosity allowing for said filtered air to freely flow therethrough while retaining and killing air-suspended bacteria therein.

Preferably, the bactericidal medium is a bactericidal fiber forming a layer of angel's hair with said porosity providing substantially no obstruction to the filtered air flowing therethrough while locally retaining and killing air-suspended bacteria therein.

Preferably, the bactericidal medium is generally uniformly distributed between said front-screen and back-screen elements.

Preferably, the body includes a fastening means connecting said front-screen element to said back-screen element and slightly squeezing said bactericidal medium therebetween; thereby preventing said bactericidal medium from being displaced by the air flowing therethrough.

Preferably, the body includes a frame connecting to said front-screen and back-screen elements.

Alternatively, the back-screen element connects to an air filter of the air duct circulation network and retains said bactericidal medium therebetween, whereby the air filter is said front-screen element.

Preferably, the fastening means is stitches generally subdividing said bactericidal after-filter device into a plurality of sub-elements.

Preferably, the bactericidal medium is an anti-dust mite medium.

Preferably, the bactericidal medium includes triclosan agent and benzyl benzoate agent.

Preferably, the bactericidal medium is Rhovyl'A.S.+™ fiber materials.

Preferably, the bactericidal medium has a density between two and ten grams per feet square.

According to another aspect of the present invention, there is provided method for cleaning and purifying a filtered air from undesirable bacteria suspended therein, the method comprises the steps of:

a) providing a body including a front-screen element facing a back-screen element for allowing filtered air to substantially perpendicularly and freely flow therethrough;

b) providing a bactericidal medium; and

c) uniformly distributing said bactericidal medium between said front-screen and back-screen elements of said body for allowing for said filtered air to freely flow therethrough while retaining and killing air-suspended bacteria therein.

Preferably, the method comprises, after step c), the steps of:

d) providing a fastening means connecting said front-screen element to said back-screen element and slightly squeezing said bactericidal medium therebetween to form a bactericidal after-filter device, thereby preventing said bactericidal medium from being displaced by the air flowing therethrough; and

e) installing said bactericidal after-filter device parallel to and downstream of an air filter of an air duct circulation network of a living enclosure.

Preferably, the bactericidal medium of step b) is provided as compacted bactericidal fibers, the method comprises, after step b), the step of:

b1) thinning out said bactericidal medium as to form a layer of angel's hair with said bactericidal fibers having a porosity providing substantially no obstruction to the filtered air flowing therethrough while locally retaining and killing air-suspended bacteria therein.

BRIEF DESCRIPTION OF THE DRAWINGS

In the annexed drawings, like reference characters indicate like elements throughout. [0034]
FIGS. 1, 1A and [0035] 1B are exploded perspective views of a first, second and third embodiments of a bactericidal after-filter device according to the present invention, respectively;
FIG. 1C is a top view of the embodiment of FIG. 1 assembled around a frame; [0036]
FIG. 2 is an exploded perspective view showing a typical use of the embodiment of FIG. 1; [0037]
FIG. 2A is a side partial section view showing an embodiment of the present invention installed inside an individual portable mask; [0038]
FIGS. 3 and 3A are enlarged top views of the embodiment of FIG. 1 showing different fastening means; and [0039]
FIG. 4 is a section view taken along line [0040] 4-4 of FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the annexed drawings the preferred embodiments of the present invention will be herein described for indicative purposes and by no means as of limitation. [0041]
Referring to FIG. 1, there is shown an [0042] embodiment 10 of a bactericidal after-filter device according to the present invention for mounting parallel to and downstream of an air filter F inside an air duct D of an air circulation network of a living enclosure, such as a human habitation or the like, to kill bacteria therefrom. The device 10 is especially made to be installed downstream of the standard air filter F in order to remain clear from dust, dirt and the like particles and therefore last longer between cleaning operations.
It is to be noted that the term “bacteria” includes all disease-causing micro-organisms, such as bacteria, fungi, yeasts, parasites (dust mites and the like) and other variety of potentially dangerous substances that can invade a human body or any other living body since they are suspended in the air that everyone breathes, and bactericidal means something that kills the above “bacteria”. A key feature of this [0043] device 10 is its ability to retain and kill (or destroy) these foreign invaders present in suspension in the preferably filtered air A flowing inside the air duct circulation network D. Air duct circulation network D also refers to any type of air heating and/or cooling and/or circulating (such as air exchangers) devices that could be wall/window units or simply transportable units, individual portable masks M and the like.
The [0044] device 10 comprises a body 20 including a front-screen element 22 facing a back-screen element 24, both allowing for the filtered air A to freely flow there through, and a bactericidal medium 30 contained in between the front-screen 22 and back-screen 24 elements of the body 20. The bactericidal medium 30 has a porosity that allows for the filtered air A to freely flow there through, without altering its speed. The bactericidal medium 30 substantially retains, or catches, the air-suspended bacteria (or other “invaders”) therein and kills the same, as illustrated in FIGS. 2 and 2A by the arrows A and A₁representing the air full and free of bacteria, respectively. In order to improve its efficiency and lifetime, the bactericidal medium 30 is placed downstream of a standard air filter F and preferably stands independently of the same as illustrated in FIGS. 2 and 2A.
The [0045] bactericidal medium 30 is preferably made out of bactericidal fibers 32 forming a non-woven layer of angel's hair with a porosity that provides substantially no obstruction for the air A flowing there through. The fibers 32 are generally roughly uniformly distributed between the front-screen 22 and back-screen 24 elements (see FIGS. 1, 1A and 1B). Such of a layer of angel's hair can have scattered porosities that widely locally vary in sizes, from tenths of a micron to many hundred microns for example, such that any size of bacteria has a chance to get retained therein. Typically, the fibers 32 are distributed to have a density varying between two (2) to thirty grams per feet square (30 gr/ft²) or more as long as no obstruction is provided to the filtered air, preferably around five (5) gr/ft².
The [0046] screen elements 22, 24 can have different sizes and shapes and can be simple typical flexible or semi-flexible type screens as illustrated in FIG. 1, made out of aluminum or fiberglass type materials, or the like. As shown in the embodiment 10 a of FIG. 1A, the body 20 a of the device can include a rigid frame 26, such as a standard aluminum screen frame, that is split into two parts 26 a, 26 a′ integral to the front 22 a and back 24 a screen elements, respectively, to make them rigid and easy to install. The device 1Oa also preferably includes a fastening means 40 to preferably releasably connect the two screen elements 22, 24 together with the bactericidal fibers 32 slightly squeezed in between to prevent it from being displaced by the air A flowing there through. The fastening means 40, shown in FIG. 1A, is a simple retainer 40 a pivoting on one of the parts 26 a′ of the frame 26 to retain the other part 26 a against the same.
Alternatively, the [0047] rigid screen 28 of any existing air filter F could directly be used as the front-screen 22 b, as shown in the embodiment 10 b of FIG. 1B.
Referring to FIGS. 1C and 2, the [0048] frame 26 is represented as a thin metallic rod onto which the front-screen 22 and back-screen 24 elements are attached. As shown in FIG. 2, the device 10 is preferably installed inside the air duct D downstream of the air filter F and upstream of the air heating system H. The frame 26 generally encloses the entire elements 22, 24 but also includes intermediate reinforcing rods 27 used to subdivide the elements 22, 24 into a plurality of smaller sub-elements 25 to constrain the bactericidal fibers 32 to remain in place between the two elements 22, 24.
In that case, the fastening means [0049] 40 is preferably made out of stitches 40 b or 40 c (represented by wavy and dashed line in FIGS. 2 and 3 respectively) or any other type of fasteners, such as rivets 40 d (see FIG. 3A), that are also used to subdivide the bactericidal after-filter device 10 into sub-elements 25 (see FIG. 4).
As illustrated in FIG. 2A, the bactericidal after-[0050] filter device 10 could be installed (preferably removably using a Velcro™ type fastener or the like, not shown) inside an individual portable mask M that are worn in front of the nose/mouth area of the individual (with the mask itself acting as an air filter F when no specific air filter F is added thereto) or the like for efficient bactericidal treatment of the air getting inside the mask M.
The [0051] bactericidal medium 30 of the present invention is treated with an anti-microbial agent, such as triclosan or the like, that kills bacteria, yeasts and fungi found within fine dust particles that are not caught by standard air filters. The commercialized product called Rhovyl'As™ is a good example of such a bactericidal medium 30. The medium 30 can further include an anti-dust mite agent, such as benzyl benzoate, that also kills dust mites and the like; the commercialized product called Rhovyl'A.S.+™ is a good example of such a bactericidal medium 30. Both Rhovyl'As and Rhovyl'A.S.+ fiber materials manufactured by Rhovyl™ Company prevent the development of bacteria and the like and bad smells. These fiber materials are either used pure (100%) or in blends, with a percentage of at least 30% volume, along with other types of fibers within woven or non-woven type fabrics, and meet the requirements of an individual protective equipment (IPE). Furthermore, the fiber materials have also important intrinsic qualities as natural and permanent non-flammability, resistance to chemical products, suppression of the risk of ignition, good thermal insulation, moisture management, etc.
Preferably, the [0052] fibers 32 form a layer of angel's hair with a porosity providing substantially no obstruction to the filtered air flowing there through while locally retaining and killing air-suspended bacteria therein. Even though the fibers 32 do not totally cover the surface area of the screens 22, 24 or retain all bacteria, they remain very efficient since the air is normally re-circulated through the air circulation network D a few times per hour such that most of the bacteria have a good chance of being captured and killed by the bactericidal after-filtering device 10.
It is to be understood that other bactericidal materials may also be efficiently used in the after-[0053] filter device 10.
Also, another aspect of the present invention refers to a corresponding method for cleaning and purifying a filtered air A from undesirable bacteria suspended therein and that comprises the steps of: [0054]
a) providing a [0055] body 20 including a front-screen element 22 facing a back-screen element 24 to allow for the filtered air to substantially perpendicularly and freely flow there through;
b) providing a [0056] bactericidal medium 30; and
c) uniformly distributing the [0057] bactericidal medium 30 between the front-screen 22 and back-screen 24 elements of the body 20 to retain and kill the air-suspended bacteria contained in the filtered air A flow there through.
Preferably, the method further includes the steps of: [0058]
d) providing a fastening means [0059] 40 to preferably releasably connect the front-screen element 22 to the back-screen element 24, and slightly squeeze the bactericidal medium 30 in between to form a bactericidal after-filter device 10;
e) installing the bactericidal after-[0060] filter device 10 parallel to and downstream of an air filter F of an air duct circulation network D of a living enclosure.
Since the [0061] bactericidal medium 30 is generally provided in the form of compacted bactericidal fibers 32 that would block the filtered air A from going through, the method can include the step of:
b1) thinning out the [0062] bactericidal medium 30 as to form a layer of angel's hair with the bactericidal fibers 32 in order to get a porosity that provides substantially no obstruction to the filtered air A flowing while locally retaining and killing air-suspended bacteria contained in the dust.
Numerous laboratory testing results showed the efficiency of the Rhovyl'A.S.+ material to destroy and kill the bacteria, from 96.6% (78.8% and 21.6% of cocci Gram-positive and rod Gram-negative type bacteria respectively) of the whole bacteria population present on the [0063] fibers 32 after zero (0) days up to 98.1% (88.9% and 11.1% of cocci Gram-positive and rod Gram-negative type bacteria respectively) after twenty-one (21) days, and from 88.3% of the whole fungi population present on the fibers 32 after zero (0) days to 92.8% after twenty-one (21) days, based on some tests performed according to the Samson method. The tests also show that, as the time goes on, the bactericidal effect efficiency of the fibers 32 of the device 10 increases.
These days, since many people are very sensitive and allergic to some bacteria, pollens, yeasts and/or fungi, the present after-[0064] filter device 10 is really a nice to have in every living place. For that reasons the bactericidal after-filter device 10 is also very applicable for different types of medical applications.
Although the present bactericidal after-filter device has been described with a certain degree of particularity, it is to be understood that the disclosure has been made by way of example only and that present invention is not limited to the features of the embodiments described and illustrated herein, but includes all variations and modifications within the scope of the present invention as hereinafter claimed. [0065]

Claims

I claim:

1. A bactericidal after-filter device for mounting parallel to and downstream of an air filter of an air duct circulation network of a living enclosure, said device comprising:

2. The device of claim 1, wherein said bactericidal medium being a bactericidal fiber forming a layer of angel's hair with said porosity providing substantially no obstruction to the filtered air flowing therethrough while locally retaining and killing air-suspended bacteria therein.

3. The device of claim 1, wherein said bactericidal medium being generally uniformly distributed between said front-screen and back-screen elements.

4. The device of claim 1, wherein said body including a fastening means connecting said front-screen element to said back-screen element and slightly squeezing said bactericidal medium therebetween; thereby preventing said bactericidal medium from being displaced by the air flowing therethrough.

5. The device of claim 1, wherein said body including a frame connecting to said front-screen and back-screen elements.

6. The device of claim 1, wherein said back-screen element for connecting to an air filter of the air duct circulation network and retaining said bactericidal medium therebetween, whereby the air filter being said front-screen element.

7. The device of claim 4, wherein said fastening means being stitches generally subdividing said bactericidal after-filter device into a plurality of sub-elements.

8. The device of claim 1, wherein said bactericidal medium being an anti-dust mite medium.

9. The device of claim 1, wherein said bactericidal medium including triclosan agent.

10. The device of claim 9, wherein said bactericidal medium including benzyl benzoate agent.

11. The device of claim 10, wherein said bactericidal medium being Rhovyl'A.S.+™ fiber materials.

12. The device of claim 10, wherein said bactericidal medium having a density between two and ten grams per feet square.

13. The device of claim 1, wherein said bactericidal medium having a density between two and ten grams per feet square.

14. A method for purifying a filtered air from undesirable bacteria suspended therein, said method comprising the steps of:

b) providing a bactericidal medium; and

15. The method of claim 14, comprising, after step c), the steps of:

16. The method of claim 14, wherein said bactericidal medium of step b) being provided as compacted bactericidal fibers, said method comprising, after step b), the step of:

17. The method of claim 16, comprising, after step c), the steps of:

d) providing a fastening means connecting said front-screen element to said back-screen element and slightly squeezing said bactericidal fibers therebetween to form a bactericidal after-filter device, thereby preventing said bactericidal fibers from being displaced by the air flowing thereth rough; and

18. The method of claim 15, wherein said bactericidal medium of step b) being provided as compacted bactericidal fibers, said method comprising, after step b), the step of:

19. The method of claim 14, wherein said bactericidal medium including triclosan agent and benzyl benzoate agent.

20. The method of claim 14, wherein said bactericidal medium having a density between two and ten grams per feet square.