# US 5,706,802 A · Cold weather breathing apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,706,802 A - Document ID: US5706802A - Status: Granted - Kind: A - Application number: 08/736,587 - Filed: 1996-10-24 - Granted: 1998-01-13 - Earliest claimed: 1996-10-24 - Inventors: Bruce McCormick - Web page: https://patentgrep.com/patent/US5706802A ## CPC - A62B 9/003: {Means for influencing the temperature or humidity of the breathing gas} - A62B: DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING (valves specially adapted for medical use A61M39/00; life-saving devices, apparatus or methods specially adapted for use in water B63C9/00; divers' equipment B63C11/00; specially adopted for use with aircraft, e.g. parachutes, ejector seats, {B64D17/00, B64D25/10}; rescue devices peculiar to mining E21F11/00) ## Abstract A breathing device including a heat exchanger module retained adjacent the mouth of a user by a fabric holder. The heat exchanger module includes a wall surrounding a non-linear, tubular flow passage extending between a first air vent and a second air vent. A heat exchanging medium comprising a woven copper cloth is disposed within the flow passage. The flow passage includes a larger cross-sectional area adjacent the first air vent than adjacent the second air vent. ## Claims ### Claim 1 A breathing device including: a heat exchanger module; said heat exchanger module including a wall surrounding an interior space; said interior space comprising a tubular flow passage including a first end and a second end; a first air vent disposed through said wall and adapted to permit both inflow and outflow of air relative to said first end of said tubular flow passage; a second air vent disposed through said wall and adapted to permit both inflow and outflow of air relative to said second end of said tubular flow passage; said tubular flow passage defining a non-linear flow path joining said first and said second air vents in fluid communication; a heat exchanging medium disposed within said tubular flow passage; and a holder supporting said heat exchanger module and adapted to retain said heat exchanger module in a position adjacent the face of a user; whereby said non-linear flow path between said first and said second air vents permits a relatively compact module to include a longer flow path within said interior space, thereby increasing the relative efficiency of said heat exchanger module by forcing longer interaction between air flowing through said flow path and said heat exchanging medium disposed within said flow path. ### Claim 2 (depends on 1) A breathing device as set forth in claim 1 wherein said heat exchanging medium comprises a woven copper cloth. ### Claim 3 (depends on 1) A breathing device as set forth in claim 1 wherein said tubular flow passage defines a u-shaped path between said first air vent and said second air vent. ### Claim 4 (depends on 1) A breathing device as set forth in claim 1 wherein said tubular flow passage includes a cross-sectional area which is larger at said first end of said flow passage than at said second end. ### Claim 5 (depends on 1) A breathing device as set forth in claim 1 including first and second tubular flow passages each joining said first air vent and said second air vent in fluid communication. ### Claim 6 (depends on 1) A breathing device as set forth in claim 1 wherein said first air vent and said second air vent are oriented in opposite directions. ### Claim 7 (depends on 1) A breathing device as set forth in claim 1 wherein said first air vent includes a larger total surface area than said second air vent. ### Claim 8 (depends on 1) A breathing device as set forth in claim 1 wherein said wall is made from a flexible material. ### Claim 9 A breathing device including: a heat exchanger module; said heat exchanger module including a wall surrounding an interior space; said interior space comprising a tubular flow passage including a first end and a second end; a first air vent disposed through said wall and adapted to permit both inflow and outflow of air relative to said first end of said tubular flow passage; a second air vent disposed through said wall and adapted to permit both inflow and outflow of air relative to said second end of said tubular flow passage; said tubular flow passage defining a flow path joining said first and said second air vents in fluid communication; said tubular flow passage including a cross-sectional area which is larger adjacent said first air vent than adjacent said second air vent; a heat exchanging medium disposed within said tubular flow passage; and a holder supporting said heat exchanger module and adapted to retain said first air vent of said heat exchanger module in a position adjacent the mouth of a user; whereby said larger cross-sectional area of said tubular flow passage adjacent said first air vent decreases the pressure and velocity of air flowing to and from the mouth of a user, forcing longer interaction of incoming air with said heat exchanging medium adjacent the mouth of a user and thereby increasing the efficiency of said heat exchanger module. ### Claim 10 (depends on 9) A breathing device as set forth in claim 9 wherein said first air vent includes a larger total surface area than said second air vent. ### Claim 11 (depends on 9) A breathing device as set forth in claim 9 wherein said heat exchanging medium comprises a woven copper cloth. ### Claim 12 (depends on 9) A breathing device as set forth in claim 9 wherein said tubular flow passage defines a u-shaped path between said first air vent and said second air vent. ### Claim 13 (depends on 9) A breathing device as set forth in claim 9 including first and second tubular flow passages each joining said first air vent and said second air vent in fluid communication. ### Claim 14 (depends on 9) A breathing device as set forth in claim 9 wherein said first air vent and said second air vent are oriented in opposite directions. ### Claim 15 (depends on 9) A breathing device as set forth in claim 9 wherein said wall is made from a flexible material. ### Claim 16 A breathing device including: a heat exchanger module; a fabric holder supporting said heat exchanger module; said fabric holder including an upper peripheral edge and a lower peripheral edge each including a midpoint; said fabric holder comprising an outer fabric layer and an inner fabric layer defining pocket therebetween; said inner fabric layer including a first opening therein and said outer fabric layer including a second opening therein: said heat exchanger module including a first air vent and a second air vent each including an outwardly extending flange surrounding said vents; said heat exchanger module being disposed within said pocket between said outer fabric layer and said inner fabric layer; said flange surrounding said first air vent being disposed through said first opening in said inner fabric layer; and said flange surrounding said second air vent being disposed through said second opening in said outer fabric layer. ### Claim 17 (depends on 16) A breathing device as set forth in claim 16 including first and second side flaps extending from opposing sides of said fabric holder; and attachment means supported on at least one of said side flaps for joining said first and said second side flaps together. ### Claim 18 (depends on 16) A breathing device as set forth in claim 16 including: an elastic strap including first and second ends; said first end and said second end being joined to said upper peripheral edge of said fabric holder at locations spaced equally from said midpoint of said upper peripheral edge.