THREE DIMENSIONAL FILTER MEDIA FOR EXTENDED LIFE FILTER
A three dimensional filter media for extended life filters includes: (a) a filter media base made of fabric selected from the group consisting of synthetic fabric, natural fabric and combinations thereof, the fabric being made of a plurality of threads, each of the plurality of threads being formed by a plurality of joined twisted thread filaments, the fabric being selected from the group consisting of woven fabric, knitted fabric, and combinations thereof, the fabric having a thickness of Z in the range of 0.020 to 0.075 inch, the fabric having a specified density; and (b) a plurality of mechanical cilia connected to and protruding outwardly and away from the base, the cilia having a length that is at least 10 times Z, Z being the thickness of the base set forth above, and having a density that is no greater than 5% of the density of the base.
This application is a divisional of, and claims the benefit of the filing date of, U.S. patent application Ser. No. 15/360,293, filed Nov. 23, 2016 (now U.S. Pat. No. 10,286,346, issued May 14, 2019) titled Three Dimensional Filter Media for Extended Life Filter, the contents of which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTIONThe present invention relates to filters.
BACKGROUND OF INVENTIONThe following patents and applications are representative of various types of vacuum cleaners and filter systems:
United States Patent Application No. 2012/0279185 A1 to Appelo describes a vacuum cleaner primary filter cage wall element that is adapted to form, together with at least one complementary filter cage wall element, a tubular bag-house filter cage segment. The filter cage wall elements are provided with snap-locks, for snapping a first long side of the primary filter cage wall element to a secondary long-side of the complementary filter cage wall element, and for snapping a secondary long side of the primary filter cage wall element to a first long side of the complementary filter cage wall element.
U.S. Pat. No. 8,533,906 B2 to Liu describes vacuum cleaner comprising a receptacle having a working air inlet and an associated filter, the filter in communication with and downstream from the working air inlet, is disclosed. The vacuum cleaner further includes a housing containing a motor and having a cooling air outlet from the motor and a working air outlet, the working air outlet in communication with the working air inlet of the receptacle through a working air impeller, wherein the cooling air is directed to the receptacle, and the cooling air passes through the filter before exiting the working air outlet of the housing.
U.S. Pat. No. 8,206,482 B2 to Williams et al. describes vacuum cleaner filters, in particular replaceable vacuum cleaner filters suitable for both dry and wet/dry type vacuum cleaners, as well as systems incorporating the use of such filters and methods for their use. The filters include a plurality of adjacently positioned pleats arranged in a closed circumferential, cylindrically-shaped path, a top end cap having a central orifice capable of constricting a post on a vacuum filter cage, and optionally a molded end ring oppositely-spaced from the top end cap for engagement with the motor housing of a vacuum cleaner.
U.S. Pat. No. 6,428,610 B1 to Tsai et al. describes a filter media for a high efficiency particulate air (“HEPA”) filter including a multiplicity of adjacent electrostatically charged piles of nonwoven fabric. The invention further includes a method of making a HEPA filter.
U.S. Pat. No. 6,113,663 to Liu describes a vacuum cleaner having a dual filter assembly includes a filter cage, a primary filter disposed on the filter cage, and a secondary filter disposed downstream of the primary filter. A float valve between the primary filter and the secondary filter inhibits liquid from coming into contact with the secondary filter.
U.S. Pat. No. 6,110,248 to Liu at al. describes a dual filter assembly for a vacuum cleaner that includes an annular inner filter mountable on a filter cage of the vacuum cleaner. The inner filter has a lower end and a retaining ring is attached to the lower end. An annular outer filter is removably mounted surrounding the inner filter, with a lower end of the outer filter supported by the retaining ring.
U.S. Pat. No. 5,855,634 to Berfield describes a filter retainer for a vacuum cleaner that includes a filter cage having several ribs. At the bottom of the filter cage is a lip which includes a plurality of notches. A cylindrical filter having open ends is slid over the filter cage. A cap is placed at the bottom of the filter in order to hold the filter to the filter cage. The cap has a pair of ramps which engage notches on the rim of the filter cage. As the cap is rotated, the cap is pushed towards the filter so that a lip on the cap engages a bottom of the filter.
U.S. Pat. No. 5,783,086 to Scanlon et al. describes an improved method of employing a wet/dry vacuum cleaner for wet material pick-up. By employing a hydrophobic and air permeable filter material, such as an expanded polytetrafluoroethylene (PTFE), with a tight gasket around its edge in a place of a conventional wet/dry vacuum filter, it has been determined that the filter can be retained in place at all times during operation, regardless of the material being collected.
U.S. Pat. No. 5,308,485 to Griffin et al. describes a filter assembly for use in a bag-house having a cell plate provided with openings. The filter assembly includes a collar, filter bag, tubular supporting cage and locking ring. The filter bag filters particulate material and extends from below the cell plate. The collar supports the filter bag and has a longitudinally extended portion and a flange portion. The longitudinally extended portion is affixed to the filter bag below the cell plate, while the flange portion extends along the cell plate as a rim above a respective opening. The collar acts as a gasket to seal a respective opening in the cell plate. The tubular supporting cage has a longitudinally extended portion that structurally supports the filter bag. The locking ring is integrally fixed to the supporting cage and locks an arrangement of the filter bag, collar and cage in place. The locking ring also can include a venturi affixed thereto to assist in filtering and cleaning operations.
U.S. Pat. No. 5,308,369 to Morton et al. describes a cylindrical filter bag including a wire mesh cage with an access opening in the cage proximate to the open end of the filter bag. A resilient snap band is provided around the outer circumference of the cylindrical filter bag. The snap band includes a pair of felt rings formed around the band and an annular groove between the rings. The snap band thus provided can be depressed into the access opening in the wire mesh cage to allow the filter bag to be readily positioned in an airtight manner within a circular hole provided in the tube sheet of a dust collector. The hole in the tube sheet is provided with a collar having a radially extended flange portion that is attached to the top surface of the tube sheet to center the collar above the hole. The wire tube mesh cage of the filter bag is further provided with a reinforcing sleeve that mates with the tube sheet collar, and a venturi that is positioned concentrically within the sleeve.
U.S. Pat. No. 5,069,696 to Bruno describes a shop type vacuum cleaner including an externally mounted filter including a filter housing including a filter element and an elongated inlet tube slidably received within an exhaust outlet opening from the vacuum cleaner debris compartment.
U.S. Pat. No. 4,906,265 to Berfield describes installing a dry material paper filter on the filter cage of an electric vacuum cleaner, a disk of porous paper filtering material or of cloth type fabric, laid over the panel enclosing the bottom of the filter cage and a ring is pressed up over the paper or cloth filter and over the panel. As the ring is drawn up over the filter cage, it folds and presses the paper or cloth filter around the filter cage. At the top of the filter cage, the ring secures the filter to the cage. An additional filtering sleeve may be disposed around the filter cage before the filter is installed over the cage and over the sleeve with the attachment ring. The sleeve may be of foam or other wet material filtering material. The filter installed with the ring is of dry filtering material, like paper or cloth. A marking or disk at the center of the filter helps a user place the filter over the filter cage before the ring is used to fold the filter into place.
U.S. Pat. No. 3,830,042 to MacDonnell describes a disposable filter bag for the intake air housing of a locomotive that has a generally rectangular box-shaped extended configuration and is of pliable sheet stock of full flow depth filter material to be collapsible for folding into compact form. The bag is mounted between external and internal cage-like frames that stabilize the extended configuration of the bag.
U.S. Pat. No. 3,478,498 to Sauermann describes a filter that comprises a frame and a filter element carried by the frame to define therewith an internal chamber. The filter element consists of two apertured supporting layers and a filter layer of fibrous filter material sandwiched therebetween. A plurality of supporting bars is located in the internal chamber and engages the inner surfaces of the filter element. A plurality of deflecting bars engage the outer surfaces of the filter element intermediate the reinforcing bars and deflect the filter element intermediate such reinforcing bars inwardly into the chamber.
U.S. Pat. No. 9,161,667 to Sobel describes a filter kit with an enhanced surface area filter and cage, for an electric power vacuum cleaner. The filter is a self-cleaning, flexible interlocking fabric having a rest position at atmospheric pressure, and a stretched position when under vacuum of a vacuum cleaner, the fabric having at least enough stretchability to increase its surface area by at least 10% in its stretched position from its rest position. When the vacuum cleaner is operating, the filter is in its stretched position and collects dust and debris, and when the vacuum cleaner is off, the filter relaxes, returns to its rest position and its surface area contracts to be self-cleaning, and a portion of the dust and debris to fall from the filter.
Notwithstanding the prior art, the present invention is neither taught nor rendered obvious thereby.
SUMMARY OF INVENTIONThe present invention is directed to three dimensional filter media that may be used in many different filter environments. Although not so limited, these uses include vacuum cleaners, shop-vacs, home, recreation vehicle and other filtering systems, commercial, industrial and institutional HVAC systems and other filtering devices and systems. They may be used to supplement (add to) or to replace the filters of embodiments just described and many other uses are contemplated, including chemical filters, gas masks, fire and emergency filtering mechanisms, etc. Unlike existing filters whether spun, woven, grid, paper, cloth, metal or electrostatic, the present invention filters are truly three dimensional with extremely elongated filter cilia on one or both sides of a thin base of woven or knitted fabric. These cilia extend in length at least ten times and preferably at least twenty times the thickness of the base, they are sparse enough to account for a small fraction of the total density or height of the present invention filter media. They last longer than conventional filters when in continuous use and are machine washable, and thus offer an even greater extended life.
The present invention is directed to a three dimensional filter media for extended life filters, which includes: (a) a filter media base made of fabric selected from the group consisting of synthetic fabric, natural fabric and combinations thereof, the fabric being made of a plurality of threads, each of the plurality of threads being formed by a plurality of joined twisted thread filaments, the fabric being selected from the group consisting of woven fabric, knitted fabric, and combinations thereof, the fabric having a thickness of Z, wherein Z is in the range of 0.020 to 0.075 inch, the fabric having a density D, including interstices, wherein D is in the range of 0.25 to 0.50 gms/cubic inch; and, (b) a plurality of mechanical cilia connected to and protruding outwardly and away from the base, the cilia having a length that is at least 10 times Z, Z being the thickness of the base set forth above, and having a density that is no greater than 5% of D, D being the density of the base set forth above.
In some embodiments of the present invention three dimensional filter media for extended life filters, the filter media base and the mechanical cilia are made of synthetic fabric selected from the group consisting of polyester, polypropylene, polyethylene, polyvinyl chlorides and combinations thereof.
In some embodiments of the present invention three dimensional filter media for extended life filters, the base is a knitted fabric.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia are one end severed filaments of the base.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia have a length of at least 20 times Z, wherein Z is the thickness of the base set forth above.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia have a density that is no greater than 2% of D, D being the density of the base set forth above.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia are non-parallel and create passage areas in the range of one micron to 0.2 inch.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia are non-parallel and create passage areas in the range of one micron to 0.01 inch.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia have an average length of 0.065 to 0.3 inch.
In some embodiments of the present invention three dimensional filter media for extended life filters, the cilia are located on only one side of the base.
In some embodiments of the present invention a method of removing airborne contaminants from an airflow stream which includes: A) providing a three dimensional filter media in a filter and positioning the filter in a path of the airflow stream, the three dimensional filter media including: (a) a filter media base made of fabric selected from the group consisting of synthetic fabric, natural fabric and combinations thereof, the fabric being made of a plurality of threads, each of the plurality of threads being formed by a plurality of joined twisted thread filaments, the fabric being selected from the group consisting of woven fabric, knitted fabric, and combinations thereof, the fabric having a thickness of Z, wherein Z is in the range of 0.020 to 0.075 inches, the fabric having a density of D, including interstices, wherein D is in the range of 0.25 to 0.50 gms/cubic inch; and, (b) a plurality of mechanical cilia connected to and protruding outwardly and away from the base, the cilia having a length that is at least 10 times Z, Z being the thickness of the base set forth above, and having a density that is no greater than 5% of D, D being the density of the base set forth above: and, B) capturing a portion of the contaminants on the cilia away from the base and capturing another portion of the contaminants on the base, so as to allow extended use of the filter to capture airborne contaminants.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the filter media base and the mechanical cilia are made of synthetic fabric selected from the group consisting of polyester, polypropylene, polyethylene, polyvinyl chlorides and combinations thereof.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the base is a knitted fabric.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia are one end severed filaments of the base.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia have a length of at least 20 times Z, wherein Z is the thickness of the base set forth above.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia have a density that is no greater than 2% of D, D being the density of the base set forth above.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia are non-parallel and create passage areas in the range of one micron to 0.2 inch.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia are non-parallel and create passage areas in the range of one micron to 0.01 inch.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia have an average length of 0.065 to 0.3 inch.
In some embodiments of the present invention method of removing airborne contaminants from an airflow stream, the cilia are located on only one side of the base. In other embodiments, the cilia are located on both sides of the base. In some embodiments of the present invention vacuum cleaner two stage filter system, the secondary filter has fabric that includes continuous filaments and cut filaments to create a brushed fabric.
Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and together with the detail description serve to explain the principles of the invention. In the drawings:
The present invention is directed to three dimensional filter media that may be used in many different filter environments, including vacuum cleaners, shop-vacs, home, recreation vehicle and other filtering systems, commercial, industrial and institutional HVAC systems and other filtering devices and systems. They may be used to supplement (add to) or replace the filters of embodiments just described and many other uses are contemplated, including chemical filters, gas masks, fire and emergency filtering mechanisms, etc. Unlike existing filters whether spun, woven, grid, paper, cloth, metal or electrostatic, the present invention filters are truly three dimensional and thus offer extended life. They capture particles away from the base so as to allow significant air flow after many more uses than their equivalent filter materials without elongated cilia. Further, once the air flow pressure or vacuum has been stopped the particles tend to fall away from the present invention cilia. Further, these present invention media can easily be shaken and used “like new” or almost “like new”. In addition, there is an electrostatic feature in many instances of the present invention devices and methods. Specifically, air flow may enter conduits or hoses for air movement through the filter media. These conduits can build up charge by attracting electrons, and the elongated cilia-containing filter media can likewise attract electrons from the air. The airborne contaminants, such as dust and debris, become positively charged and will carry a charge across filter media. Thus, much of these contaminants will be held by the static opposing charges. As soon as the air flow is stopped, the charge dissipates and much of the debris falls off the filter. This is known as triboelectric effect, caused by frictional contact between different materials. The triboelectric effect is not important or noticeable with other (prior art) filter media because the debris becomes entrapped as it reaches the potentially charged filter grid, and therefore when the charge dissipates, the entrapped debris does not fall off. In the present invention media, the elongated (very elongated-10, 20 or more times longer than the thickness of the base) cilia are charged floaters that attract and suspend debris until the debris falls. This is an important feature of present invention filter media that is not found or even possible in prior art paper, metal or even cloth filters. Finally, and very significantly, these present invention filter media are environmentally friendly because they can be repeatedly washed in any washing machine and reused.
In addition to the foregoing, the present invention filter media have the unique characteristic of truly having variable density. It can be said that spun filters that comprise layers of fiberglass or other random spun filaments have variable density in the sense that if one were to take density measurements at various points about the filter, different density results would probably be obtained. However, present invention filter media have a very light density portion with a “step-function” change to a very high density portion at the interface between the cilia and the media base. This drastic variation in density is not found in any prior art filters and affords the present invention filter media with the features of a sparse floating cilia of very light density and a subsequent high density base to catch large disruptive particles.
Table I below illustrates the improvements achieved with the present invention filter media, of the present invention is employed as compared to an Original Equipment Manufacturer (OEM) filter. In summary, some of the important features of the present invention filter media are shown in Table I:
As examples of use of present invention devices, hundreds of users received products and some sent back testimonials. Following are samples of these testimonials in support of superiority over conventional filters. These users applied the present invention (fleece) filter media with cilia to various models of vacuum cleaners. The advertising indicated that these (present invention) products filtered better and lasted longer than conventional filters:
Although not a formal study, the foregoing establishes the efficacy and superiority of the present invention filter media compared to conventional filters based on independent third party users.
Although particular embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those particular embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.
Claims
1. A method of removing airborne contaminants from an airflow stream which comprises:
- providing a three dimensional filter media in a filter and positioning said filter in a path of said airflow stream, said three dimensional filter media comprising: a filter media base made of fabric selected from the group consisting of synthetic fabric, natural fabric and combinations thereof, said fabric being made of a plurality of threads, each of said plurality of threads being formed by a plurality of joined twisted thread filaments, said fabric being selected from the group consisting of woven fabric, knitted fabric, and combinations thereof, said fabric having a thickness of Z, wherein Z is in the range of 0.020 to 0.075 inch, said fabric having a density, including interstices, of D wherein D is in the range of 0.25 to 0.50 gms/cubic inch, and a plurality of mechanical cilia connected to and protruding outwardly and away from said base, said cilia having a length that is at least 10 times Z, Z being the thickness of said base set forth above, and having a density that is no greater than 5% of D, D being the density of said base set forth above; and
- capturing a portion of said contaminants on said cilia away from said base and capturing another portion of said contaminants on said base, so as to allow extended use of said filter to capture airborne contaminants.
2. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said filter media base and said mechanical cilia are made of synthetic fabric selected from the group consisting of polyester, polypropylene, polyethylene, polyvinyl chlorides and combinations thereof.
3. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said base is a knitted fabric.
4. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia are one end severed filaments of said base.
5. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia have a length of at least 20 times Z, wherein Z is the thickness of said base set forth above.
6. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia have a density that is no greater than 2% of D, D being the density of said base set forth above.
7. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia are non-parallel and create passage areas in the range of one micron to 0.2 inch.
8. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia are non-parallel and create passage areas in the range of one micron to 0.01 inch.
9. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia have an average length of 0.065 to 0.3 inch.
10. The method of removing airborne contaminants from an airflow stream of claim 1, wherein said cilia are located on only one side of said base.
Type: Application
Filed: May 6, 2019
Publication Date: Aug 22, 2019
Inventor: Martin Sobel (Flemington, NJ)
Application Number: 16/404,684