IP Library › Granted Patent US 12,539,484
Granted Patent B2
US 12,539,484 · App. 17/592,319 · Granted Feb 3, 2026

Collapsible and foldable pleated disposable air filter

Inventor: Winston Mok (San Francisco, CA)
Assignee: Woosh Air Inc.
B01D46/522B01D46/0001B01D46/0005B01D2265/04
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Quick Facts
Patent No.
US 12,539,484
App. No.
17/592,319
Granted
Feb 3, 2026
Kind
B2
Abstract

A foldable and disposable air filter media for insertion into an air filter frame is disclosed. The air filter media includes two or more filter pleated strips that are joined together. The outer edges of the air filter media are fixed to the frame to form the air filter. Each of the filter pleated strips have a number of pleats that increase the area to reduce pressure drop across the filter media while allowing air flow through to remove unwanted particles from the filtered air. A folding crease is formed between the opposite border edges of the air filter media allowing the air filter media to be folded for shipping or disposal.

Claims (23)

1 . A foldable and disposable air filter media configured to be enclosed in a fixed size frame meeting established HVAC standards, the air filter media comprising:

a plurality of filter strips joined to each other having border edges to define opposite widthwise border edges and opposite lengthwise border edges, wherein the border edges have hot pressed seals to prevent air leakage around edges of the filter media, wherein each of the plurality of filter strips includes a plurality of pleats each having a triangular shape, wherein the triangular shape is formed by two trapezoid shaped sides, each of the sides having a bottom edge, a parallel top edge, a pair of tapered side edges each joining one end of the bottom edge to one end of the top edge, the tapered side edges being symmetrical and being tapered at an identical angle relative to the bottom edge, the top edges joined together to from an apex of the triangular shape, wherein the top edges are shorter than the bottom edges to define a tapered space between bordering filter strips to accommodate a tapered cross support of the fixed size frame between the bordering filter strips; and

a first folding crease formed between one of the width wise or lengthwise opposite border edges allowing the filter strips to be folded.

2 . The air filter media of claim 1 , wherein each of the plurality of pleats is comprised of synthetic filter media having a top filtration layer and a back supporting layer.

3 . The air filter media of claim 2 , wherein the filtration layer is one of spun fiberglass material, pleated paper, cotton, a synthetic blend, graphite, foam, a flexible metal blend, or cloth.

4 . The air filter media of claim 1 , wherein a seam is formed by joining the filter strips via one of gluing, sewing, melting, welding or taping.

5 . The air filter media of claim 1 , wherein, the air filter media is configured to be folded at least once on the first folding crease and the folded air filter media is a size that fits in a standard sized shipping envelope.

6 . The air filter media of claim 1 , further comprising a second folding crease on the border edges perpendicular to the first folding crease.

7 . The air filter media of claim 4 , wherein the seam formed by joining the filter strips forms the first folding crease.

8 . An air filter assembly comprising:

a foldable air filter media including:

a plurality of filter strips joined to each other having border edges to define opposite widthwise border edges and opposite lengthwise border edges, wherein each filter strip comprise a plurality of pleats each including two trapezoid shaped sides joined to form a triangular shape, wherein each of the trapezoid shaped sides have a bottom edge, a parallel top edge, and a pair of tapered side edges each joining one end of the bottom edge to one end of the top edge, the tapered side edges being symmetrical and being tapered at an identical angle relative to the bottom edge, the top edges joined together to from an apex of the triangular shape, and wherein the border edges perpendicular to the pleats are formed via a hot press to prevent air leak; and

a folding crease formed between one of the opposite widthwise border edges or opposite lengthwise border edges allowing the filter strips to be folded; and

a fixed size frame meeting established HVAC standards, the fixed size frame having a top cover and a frame base for holding the foldable air filter media, wherein the top cover is attached to the frame base to enclose the foldable air filter media, wherein each of the opposite width wise border edges and the opposite lengthwise border edges rest on corresponding flat borders of the frame base and are pinched by corresponding flat borders of the top cover.

9 . The air filter assembly of claim 8 , wherein each of the plurality of pleats are formed in a mold.

10 . The air filter assembly of claim 8 , wherein each of the plurality of pleats of the filter media is comprised of a self-supporting synthetic filter media that comprises one or more of spun fiberglass material, pleated paper, cotton, a synthetic blend, graphite, foam, a flexible metal blend, or cloth.

11 . A foldable disposable air filter media for being held by a fixed frame having a size meeting HVAC standards, the air filter media comprising:

at least two air filter media strips, wherein one edge of a first air filter media strip is attached to an edge of a second air filter media strip to form two parallel widthwise outer edges and two parallel lengthwise outer edges to define the air filter media; and

a first folding crease formed in either of the two parallel width outer edges or the two parallel lengthwise outer edges of the attached air filter media strips, wherein each filter media strip comprises a plurality of pleats, the plurality of pleats each including two trapezoid shaped sides joined to form a triangular shape; and wherein border edges of the filter strips are joined to each other to define opposite width wise border edges and opposite lengthwise border edges, wherein each of the border edges include hot pressed seals to prevent air leakage, and wherein each of the trapezoidal shaped sides have a parallel bottom edge, a top edge, and a pair of tapered side edges each joining one end of the bottom edge to one end of the top edge, the tapered side edges being symmetrical and being tapered at an identical angle relative to the corresponding bottom edge, the top edges joined together to from an apex of the triangular shape, and wherein the top edges are shorter than the corresponding bottom edges to define a tapered space between the first and second air filter media strips to accommodate a tapered support of the fixed frame between the bordering filter strips.

12 . The foldable disposable air filter media of claim 11 , wherein each of the plurality of pleats is either comprised of synthetic filter media having a top filtration layer and a back supporting layer or made with a self-supporting filter layer.

13 . The foldable disposable air filter media of claim 11 , wherein a seam is formed by joining the first and second filter media strips via one of gluing, sewing, melting, welding or taping.

14 . The foldable disposable air filter media of claim 12 , wherein the self-supporting filter layer is one of spun fiberglass material, pleated paper, cotton, a synthetic blend, graphite, foam, a flexible metal blend, or cloth.

15 . The foldable disposable air filter media of claim 11 , further comprising a second folding crease formed in either the two parallel width outer edges or the two parallel length wise outer edges of the attached air filter media strips, the second folding crease perpendicular to the first folding crease.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 7, 2022
From: MOK, WINSTON
To: WOOSH AIR INC.
Reel/Frame 061017/0400 →
Continuity (2)
Provisional Application 63244052 · Sep 14, 2021
Related Publication 20230089672A1 · Mar 23, 2023
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