The present disclosure relates to air filters and methods of using and installing those air filters. More particularly, it relates to air filters expandable from a collapsed arrangement to an expanded, end-use arrangement.
Disposable air filters are commonly used in forced air systems (e.g., residential heating and air-conditioning systems) in order to remove dust and dirt particles and the like. HVAC air filters typically include a filter media surrounded and supported by a frame. Additional supporting and/or reinforcing components, such as a mesh screen, adhesive beads, etc., may also be included. After a period of use, the filter media becomes dirty or clogged (e.g., loaded with captured particulates), and must be replaced. This is accomplished by replacing the entire air filter. Because the frame (and other reinforcing components where provided) is discarded with the air filter even though it is only the filter media that is no longer functional, there may be unnecessary waste and cost associated with conventional HVAC air filters.
In addition to supporting the filter media, the frame defines a perimeter size and shape of the HVAC air filter, and is normally selected to match the size and shape of the expected end-use application. For example, many residential HVAC systems are configured for use with a “standard” sized air filter of 20″×20″×1″ or 20″×25″×1″. The rigid frame dictates that the HVAC air filter has this same size as shipped to a retailer, as presented to potential purchasers, and as stored by an end user. Because these typical HVAC air filters are thus rather bulky, they undesirably occupy a relative large volume of space on transportation vehicles and retailer shelves. Further, consumers may view the purchase, handling and storage of the bulky HVAC air filters as less than optimal.
In light of the above, a need exists for a disposable air filter that overcomes one or more of the above-mentioned problems associated with conventional, disposable HVAC air filters.
One embodiment of an air filter 20 in accordance with principles of the present disclosure is shown in
The pleated filter media assembly 30 can assume a wide variety of forms useful for HVAC air filtration presently known, or in the future developed. As used herein, the term “pleated” refers to a web at least a portion of which has been folded to form a configuration comprising rows of generally parallel, oppositely oriented folds. For example, and as shown in
The pleated filter media assembly 30 can consist of a pleated filter media or web 60 alone (as in the illustrated embodiment), or can include one or more additional components or structures applied or assembled to a pleated filter media 60 so long as the resultant pleated filter media assembly 30 can at least be transitioned from the collapsed condition to the expanded condition without damaging a structural integrity of the pleated filter media assembly 30, and optionally can be repeatedly transitioned between the collapsed and expanded conditions without damaging a structural integrity of the pleated filter media assembly 30. The pleated filter media 60 of the assembly 30 can be self-supporting or non-self-supporting. For example, where the pleated filter media assembly 30 consists of the pleated filter media 60 alone, the pleated filter media or web 60 can be self-supporting or non-self-supporting. Where the pleated filter media assembly 30 consists of the pleated filter media or web 60 and a support structure, the pleated filter media 60 can be non-self-supporting with the addition supporting structure rendering the pleated filter media assembly 30, as a whole, to be self-supporting. As used herein, the term “self-supporting” with respect to filter media describes filter media that satisfies at least one of the following conditions: (1) a filter media or web that is deformation resistant without requiring stiffening layers, adhesive or other reinforcement in the filter media web; or (2) the filter media generally maintains its shape when subjected to an airstream as described, for example, in U.S. Pat. No. 7,169,202 to Kubokawa, the entire teachings of which are incorporated herein by reference; or (3) a web or media having sufficient coherency and strength so as to be drapable and handleable without substantial tearing or rupture. As used herein, the term “non-self-supporting” can denote an air filter media that does not satisfy at least one of the above conditions.
Any desired filter media 60 having the desired characteristics can be used in the filter media assembly 30. For example, the filter media 60 can be constructed, for example, from nonwoven fibrous media formed of thermoplastics or thermosetting materials such as polyolefins including polypropylene, HDPE, LDPE, LLDPE and metallocene polyolefins; polyesters including aromatic and aliphatic polyesters, polyamides such as nylon 6, nylon 6,6, nylon 12, etc.; natural fibers including cellulose fibers such as rayon, cotton, and the like, acrylic fibers, olefin copolymers such as EMA, EVA and the like, Teflon, polyurethanes, polyvinyl chloride and combinations thereof. Other suitable, non-limiting materials for the filter media include porous foams, nonwovens, papers, fiberglass, or the like. The pleated filter media assembly 30 can optionally include a highly open wire mesh or screen, one or more adhesive strands, etc., is bonded to the filter media 60 in order to enhance the pleatability thereof and that is pleated along with the filter media 60 itself.
In some embodiments, the filter media 60 comprises a nonwoven web that can have random fiber arrangement and generally isotropic in-plane physical properties (e.g., tensile strength), or if desired may have aligned fiber construction (e.g., one in which the fibers are aligned in the machine direction as described in U.S. Pat. No. 6,858,297 to Shah et al., the teachings of which are incorporated herein by reference) and anisotropic in-plane physical properties. Some or all of the fibers comprising the nonwoven webs useful with the filter media 60 can be multicomponent fibers having at least a first region and a second region, where the first region has a melting temperature lower than the second region. Some suitable multicomponent fibers are described, for example, in U.S. Pat. Nos. 7,695,660, 6,057,256, 5,597,645, 5,972,808, 5,662,728 and 5,486,410 the teachings of each of which are incorporated herein by reference in their entireties.
Other nonwoven webs useful with the filter media 60 can be a high loft spunbond web, such as described, for example, in U.S. Pat. No. 8,162,153 to Fox et al., the entire teachings of which are incorporated herein by reference. In other embodiments, the filter media 60 can be a low loft spunbond web, such as those described in U.S. Pat. No. 7,947,142 to Fox et al., the entire teachings of which are incorporated herein by reference. In yet other embodiments, nonwoven webs useful with the filter media 60 are generated by other techniques and/or have other characteristics, such as the meltblown nonwoven webs disclosed in U.S. Pat. No. 6,858,297 to Shah et al. (mentioned above). Other non-limiting example of useful nonwoven web formats include bi-modal fiber diameter meltblown media such as that described in U.S. Pat. No. 7,858,163, the entire teaching of which are incorporated herein by reference.
In some embodiments, an electrostatic charge is optionally imparted into or on to material(s) of the filter media 60. Thus, the filter media 60 can be an electret nonwoven web. Electric charge can be imparted to the filter media 60 in a variety of ways as is well known in the art, for example by hydrocharging, corona charging, etc. (e.g., as described in U.S. Pat. No. 7,947,142 (mentioned above)). In other embodiments, the filter media 60 is not electrostatically charged.
Pleats can be formed in the filter media 60 (or in the pleated filter media assembly 30) using various methods and components as are well known in the art, e.g., to form a pleated filter for use in applications such as air filtration, for example those described in U.S. Pat. No. 6,740,137 to Kubokawa et al. and U.S. Pat. No. 7,622,063 to Sundet et al., the entire teachings of both of which are incorporated herein by reference.
Returning to
The shape retention structure(s) 34 can assume a wide variety of forms, and is generally configured to retain the pleated filter media assembly 30 in the selected expanded condition (and thus the air filter 20 in the selected expanded state). In the exemplary embodiment of
For example, the shape retention structures 34a, 34b can be or include a curable composition such as a moisture/water curable composition such as plaster of Paris, cyanoacrylates such as ethylcyanoacrylate, or a water curable isocyanate functional resin such as Scotchcast™ Plus casting tape available from 3M Company of St. Paul, Minn. Suitable isocyanate functional resin systems are disclosed in U.S. Pat. No. 4,667,661 incorporated herein by reference. Additionally, the moisture curable resin could be a silane functional resin such as but not limited to that disclosed in U.S. Pat. No. 5,540,652, the entire teachings of which are incorporated herein by reference. For moisture curable retention means, importantly, moisture is prevented from curing the composition prior to use with appropriate barrier packaging either hermetically enclosing the curable composition or the entire air filter 20. Alternatively, the moisture curable resin could be replaced or augmented with a polymeric dispersion or solution in water or solvent and simple evaporation results in drying such as a latex or lacquer paint resulting in enhanced rigidity.
In other embodiments, the shape retention structures 34a, 34b are made of a deformable metal. For example, the shape retention structures 34a, 34b can be aluminum strips.
While two of the shape retention structures 34a, 34b are shown, other numbers, either greater or lesser, are also acceptable. For example, in other embodiments, the air filter 20 can include one or more additional shape retention structures akin to the shape retention structures 34a, 34b described above, but more centrally located along a length of the pleated filter media assembly 30.
The air filter 20 is initially arranged in the collapsed state (
When the user is ready to install the air filter 20 to an HVAC system, the user simply pulls on the two end members 32a, 32b to stretch the pleated filter media assembly 30 to a desired size corresponding with the filter receiving housing or bay of the HVAC system. As a point of reference, where the HVAC system's filter receiving bay is sized and shaped for use with a 20″ (width)×25″ (length)×1″ (depth) air filter, the air filter 20 can have a width on the order of 20″ and a depth on the order of 1″ in both the collapsed and expanded states, and can be arranged in the expanded state to have a length on the order of 25″. However, in the collapsed state, the air filter 20 will have a length much less than 25″ (e.g., less than 50% of the length in the expanded state). The shape retention structure(s) 34 is configured to allow desired stretching of the pleated filter media assembly 30. Once the air filter 20 has been stretched to the desired size (e.g., desired length), the shape retention structure(s) 34 secures and holds the pleated filter media assembly 30 to the selected size. For example, with embodiments in which the shape retention structure(s) 34 is a curable moldable material (e.g., Scotchcast™ Plus casting tape or plaster), water or other liquid is applied to the shape retention structure(s) 34, or they are simply exposed to ambient humidity or both, while in the collapsed condition to activate the material of the shape retention structure(s); the so-activated shape retention structure(s) 34 will then readily allow the pleated filter media assembly 30 to be stretched by the to the desired expanded state. The user then holds the air filter 20 in the selected expanded state, allowing the shape retention structure(s) 34 to cure. Once cured, the air filter 20 can be inserted into the HVAC system and will perform to filter contaminants from the HVAC system's airflow. Alternatively where the shape retention structure(s) 34 are a deformable metal, after stretching the pleated filter media assembly 30 to a desired length, the user manipulates the shape retention structure(s) 34 (e.g., squeezing or pressing) to engage the pleats. Regardless, the shape retention structure(s) 34 maintains its strength in the expanded state to ensure the integrity of the air filter 20.
When the pleated filter media assembly 30 becomes clogged or dirty, the air filter 20 is removed from the HVAC system and discarded. Unlike conventional HVAC air filters, the air filters of the present disclosure (such as the air filter 20) do not include frame members along all edges or sides of the pleated filter media assembly 30, thus reducing overall costs and waste.
Another embodiment air filter 100 in accordance with principles of the present disclosure is shown in
In some embodiments, an attachment mechanism such as, for example, adhesive, hook and/or loop materials and/or dual lock materials can be provided with at least the arms 106, 108 to hold the pleated filter media assembly 30 in one or both of the collapsed and expanded states. For example, loop material could be added to select regions of the pleated filter media assembly 30. Alternatively, some embodiments of the pleated filter media assembly 30 inherently form “loop” structures along the filter media. Hook material can be added to the filter side of the arms 106, 108. The hook material would engage with the pleat tips in the collapsed state, with the arms 106, 108 thus serving to retain the pleated filter media assembly 30 in the collapsed state. To deploy or articulate the arms 106, 108, the arms 106, 108 are lifted off of the pleated filter media assembly 30, rotated as desired, and then re-attached. Further, the so-constructed arms 106, 108 could be used at the ends of the pleated filter media assembly 30 and collapse toward the center to support the ends.
Where provided, the secondary shape retention structures 104a, 104b can be applied or mounted to the pleated filter media assembly 30 at or immediately adjacent a respective one of the sides 50a, 50b. The secondary shape retention structures 104a, 104b are deformable and can assume various forms that provide support or reinforcement to the pleated filter media assembly 30 at least in the expanded state. For example, the secondary shape retention structures 104a, 104b can be a soft metal. In other embodiments, the secondary shape retention structures 104a, 104b can be any of the formats described above with respect to the shape retention structures 34a, 34b (
The air filter 100 can initially be in the collapsed state (and thus has a compact volume) during shipping, storage, and/or on the retailer's shelves. The air filter 100 can optionally include additional components (e.g., packaging) that holds the air filter 100 in the collapsed state. When the user is ready to install the air filter 100 to an HVAC system, the user simply pulls on the two end members 32a, 32b to stretch the pleated filter media assembly 30 and articulate the primary shape retention structure 102 to the expanded state of
The air filters of the present disclosure provide a marked improvement over previous designs. The air filters can be collapsed to save shelf-space and transportation space. The collapsed filter can be easily expanded to it usable form, making it easy for end-users to use the air filter. Further, the expanded filter is self-supported, requiring no frame material.
Although specific embodiments of the present disclosure have been shown and described herein, it is understood that these embodiments are merely illustrative of the many possible specific arrangements that can be devised in application of the principles of the present disclosure. Numerous and varied other arrangements can be devised in accordance with these principles by those of ordinary skill in the art without departing from the spirit and scope of the present disclosure. Thus, the scope of the present disclosure should not be limited to the structures described in this application, but only by the structures described by the language of the claims and the equivalents of those structures.
Number | Name | Date | Kind |
---|---|---|---|
4439219 | Lambrecht | Mar 1984 | A |
4667661 | Scholz | May 1987 | A |
4758460 | Spicer | Jul 1988 | A |
5022901 | Meunier | Jun 1991 | A |
5273564 | Hill | Dec 1993 | A |
5486410 | Groeger | Jan 1996 | A |
5540652 | Callinan | Jul 1996 | A |
5597645 | Pike | Jan 1997 | A |
5662728 | Groeger | Sep 1997 | A |
5968217 | Stein | Oct 1999 | A |
5972808 | Groeger | Oct 1999 | A |
6057256 | Krueger | May 2000 | A |
6740137 | Kubokawa | May 2004 | B2 |
6858297 | Shah | Feb 2005 | B1 |
7037354 | Dimicelli | May 2006 | B1 |
7169202 | Kubokawa | Jan 2007 | B2 |
7497888 | Ashwood | Mar 2009 | B2 |
7537630 | Schuld | May 2009 | B2 |
7622063 | Sundet | Nov 2009 | B2 |
7695660 | Berrigan | Apr 2010 | B2 |
7858163 | Angadjivand | Dec 2010 | B2 |
7947142 | Fox | May 2011 | B2 |
8157881 | Anoszko | Apr 2012 | B1 |
8162153 | Fox | Apr 2012 | B2 |
9682339 | Jursich | Jun 2017 | B2 |
20030029146 | Quigley | Feb 2003 | A1 |
20030066274 | Fredrick | Apr 2003 | A1 |
20030066275 | Schuld | Apr 2003 | A1 |
20030066424 | Shah | Apr 2003 | A1 |
20030066425 | Shah | Apr 2003 | A1 |
20030230061 | Kubokawa | Dec 2003 | A1 |
20040182055 | Wynn | Sep 2004 | A1 |
20070289273 | Boyd | Dec 2007 | A1 |
20090186151 | Vijayakumar | Jul 2009 | A1 |
20090266041 | Schrage | Oct 2009 | A1 |
20120225600 | Rule | Sep 2012 | A1 |
20120272829 | Fox | Nov 2012 | A1 |
20120317944 | Lise | Dec 2012 | A1 |
20130091818 | Anoszko | Apr 2013 | A1 |
20130133301 | Sproule | May 2013 | A1 |
20150231547 | Schrage | Aug 2015 | A1 |
20150267927 | Zhang | Sep 2015 | A1 |
20160023149 | Schouweiler | Jan 2016 | A1 |
Number | Date | Country | |
---|---|---|---|
20160263515 A1 | Sep 2016 | US |
Number | Date | Country | |
---|---|---|---|
62131917 | Mar 2015 | US |