Water-proof air-pressure equalizing valve

• US 4,071,040 A
• Filed: 03/18/1976
• Issued: 01/31/1978
• Est. Priority Date: 03/18/1976
• Status: Expired due to Term

• Current Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Original Assignee: North Electric Company
• Inventors: Moriarty, Lawrence James
• Primary Examiner(s): Cohan, Alan
• Application Number:
  US05/667,895
• Time in Patent Office: 684 Days
• Field of Search: 137/199, 137/197, 55/524, 210/510, 179/179, 220/374, 174/16 R, 174/14 R, 98/1
• US Class Current: 137/199
• CPC Class Codes: F21V 31/03 with provision for venting for vehicle head lights F21S45/33; for vehicle rear lights F21S41/192
• CPC Class Codes: H04M 1/03 Constructional features of telephone transmitters or receivers, e.g. telephone hand-sets
• CPC Class Codes: Y10T 137/309 Fluid sensing valve

Abstract

A water-proof air-pressure equalizing valve for an enclosure capable of being pressurized to match a wide range of ambient air pressures including that corresponding to the pressure of several feet of water when totally submerged, such as the instrument housing of a military-type field telephone set, comprises a sandwich structure having a thin air-permeable hydrophobic membrane clamped between two rigid perforated sheets providing mechanical support against deformation due to water or air pressure.

Claims

1. A gaseous relief valve for an enclosure containing delicate electronic communication equipment which must be pressurized over a range of gas pressures and protected against immersion in a liquid comprising:

a. a housing for said equipment defining an aperture,

b. a first sheet of thin, gas-permeable, liquid-repellent material incapable of withstanding substantial liquid pressure without deformation or rupture;

c. second and third sheets of a mechanically-rigid gas-permeable material disposed on opposite sides of said first sheet, said second and third sheets each having one surface in physical contact with an adjoining surface of said first sheet over substantially the entire surface area thereof, thereby forming a mechanically-rigid sandwich without voids between adjoining surfaces of said sheets; and

d. sealing means for retaining said three sheets in a fixed position across said aperture.

2. In a telephone station set or the like having a sealed hollow enclosure which must withstand immersion in several feet of water without adverse effect on apparatus contained within said enclosure, an air-pressure relief valve communicating between the interior of said enclosure and the exterior environment comprising in combination:

a. a housing for said valve extending through a wall of said enclosure and defining an aperture therethrough;

b. a pair of rigid, porous, corrosion-resistant discs extending across said aperture;

c. a thin, flexible membrane of air-permeable hydrophobic material interposed between said discs, said membrane being incapable of withstanding substantial water pressure without deformation or rupture, said membrane being in physical contact with each of said discs over substantially the entire adjoining surface area of said membrane;

d. said discs and interposed membrane forming a rigid sandwich structure without voids between adjoining surfaces of said membrane and said discs which is capable of withstanding substantial water pressure without deformation or rupture of said membrane while permitting passage of air therethrough;

e. means providing a water-tight seal between the edges of said discs and the inner wall of said housing; and

f. resilient clamping means for retaining said sandwich structure within said housing across said aperture.