×

Rebreathing mask

  • US 4,799,477 A
  • Filed: 03/28/1988
  • Issued: 01/24/1989
  • Est. Priority Date: 03/28/1988
  • Status: Expired due to Fees
First Claim
Patent Images

1. A face mask for enclosing the nose and mouth of humans and defining a chamber from and into which a person may inhale and exhale gases comprising:

  • an inflatable bladder that encircles the chamber;

    means for providing a substantially continuous barrier of breathable gas from said bladder, to surround the chamber, said means comprising perforations formed in said bladder and spaced therearound, certain of said perforations being elliptical in shape, the major axis of each elliptical perforation extending generally toward the major axis of adjacent perforations; and

    means for introducing a breathable gas into said chamber and said bladder, the breathable gas introduced into said bladder escaping through said perforations to provide said substantially continuous barrier of breathable gas.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×