Collapsible extended surface filter and air cleaner system using collapsible extended surface filter

A rail system to support a collapsible air cleaner filter comprising:

• a first rail guide having at least one rail edge and a plurality of support arm receiving apertures;
• a second rail guide opposing the first rail guide, the second rail guide having at least one rail edge and a plurality of support arm receiving apertures;
• and
• a plurality of support arms coupled to and extending between the first and second rail guides, each of the plurality of support arms having a first end keyed to engage and be received by one of the plurality of support arm receiving apertures provided on the first rail guide and a second end keyed to engage and be received by one of the plurality of support arm receiving apertures provided on the second rail guide.

An air cleaner filter assembly comprising:

• an air duct having a first wall and a second wall;
• a first support member coupled to the first wall;
• a second support member coupled to the second wall;
• an air filter having a first end member opposing a second end member, a media filter extending between the first and second end members, the media filter having at least one first end portion and at least one second end portion, the filter media extending a first length between the first and second end portions, the first end member extending a second length, the second end member extending a third length, the first end member provided generally parallel to the second end member, and the first length being greater than the second length and the third length;
• the air filter being removably retained in the air duct, such that the first end member engages the first support member to form an effective seal between the air filter and the first wall, and the second end member engages the second support member to form an effective seal between the air filter and the second wall, such that the media filter is provided in an extended position across the air duct.