Flame arresting air filter element

• US 4,268,289 A
• Filed: 01/28/1980
• Issued: 05/19/1981
• Est. Priority Date: 04/11/1979
• Status: Expired due to Term

• Current Assignee: Barbron Corporation
• Original Assignee: Barbron Corporation
• Inventors: Polaner, Mardy
• Primary Examiner(s): Prunner, Kathleen J.
• Application Number:
  US06/115,828
• Time in Patent Office: 477 Days
• Field of Search: 55/482, 55/486, 55/498, 55/510, 55/524-526, 55/DIG. 5, 29/6.1, 29/6.2, 29/163.5 F, 113/116 A
• US Class Current: 55/486
• CPC Class Codes: B01D 2239/0457 Specific fire retardant or heat resistant properties apparatus incorporating such gas filtering material B01D46/0093
• CPC Class Codes: B01D 2239/0478 on a layer of the filter
• CPC Class Codes: B01D 2239/0681 The layers being joined by gluing
• CPC Class Codes: B01D 2239/10 Filtering material manufacturing
• CPC Class Codes: B01D 2267/40 Different types of filters
• CPC Class Codes: B01D 2279/60 for the intake of internal combustion engines or turbines intake systems for vehicles comprising filters F02M35/024
• CPC Class Codes: B01D 39/12 of wire gauze; of knitted wire; of expanded metal
• CPC Class Codes: B01D 46/0093 against fire or explosion
• CPC Class Codes: B01D 46/2411 Filter cartridges
• CPC Class Codes: B01D 46/521 using folded, pleated material
• CPC Class Codes: Y10S 55/05 Methods of making filter
• CPC Class Codes: Y10T 29/49604 Filter

Abstract

A flame arresting filter element for air intake systems has an outer ring of pleated filtering paper and an inner, concentric ring formed of expanded metal foil, longitudinally stretched and laterally compressed so as to be adapted to diffuse and quench frames resulting from engine backfire. The inner ring is coated with a relatively inert, cohesive substance to provide a unitary structure. The two rings are provided with resilient end caps.

Claims

1. An improved air filter element of the type having an annulus of porous material for the filtering of particulate contaminants in air entering a carburetor intake or the like, wherein the improvement comprises:

an annulus formed by longitudinally folding an elongated section of expanded metal foil, stretching the folded section by applying opposed longitudinal forces, rolling the stretched section into annular form and pressing the section to reduce its axial dimension and increase its density, the metal annulus being concentrically disposed within the annulus of porous material in order to provide flame arresting capabilities of the filter element.

2. The air filter element of claim 1 wherein the expanded metal foil is steel.

3. The air filter element of claim 1 wherein the annulus of expanded metal foil is coated with ethylene plastic.

4. The air filter element of claim 3 wherein the ethylene plastic is polyolefin.

5. The air filter element of claim 1 wherein the inner radial surface of the annulus of porous material and the outer radial surface of the annulus of expanded metal foil are in substantially mating relationship.