A frigid air respirator comprising a cylindrical housing affixed to a face mask, openly constructed so as to permit the passage of air upon inhalation by the user into the chamber formed by the housing. A heating means is situated within the housing to increase the temperature of incoming air by radiation and a transversely positioned intake valve governs the admission of air into the respiratory tract of the user and divides the chamber formed by the housing into an internal chamber which is contiguous with the mask cavity and into a receiving chamber wherein a supply of previously heated air is stored prior to inhalation. An exhaust valve is encompassed into the device to allow the expulsion of air from the internal chamber and mask cavity.
A self-contained breathing assembly of the positive pressure type including a remotely positioned improved pressure demand regulator for substantially instantaneous response for breathing air having reduced operating parts substantially reducing potential breakdown and wherein there is provided a gas flow disconnect assembly between the user facepiece and gas conduits.
Described briefly, according to a typical embodiment of the present invention, a breathing mask is provided which has the intake air heater and heat and moisture exchange media located below the nose and situated for minimum exposure to heat transfer to the exterior. The mounting thereof is somewhat cantilevered from the mask, to minimize direct heat transfer to the exterior. Electric heating element means are provided and supplied from an energy pack mounted in the mask itself at a relatively low level. Some of the inhaled air passes through a first filter and moisture collecting medium to the mouth and/or nose of the individual wearing the mask. All inhaled air passes through a heat exchanger and a second filter and moisture exchanger. A valve is provided so that all air exhaled during normal respiration passes through both of the moisture exchangers. A second valve is provided in the wall of the mask to permit exhalation of any air exceeding that which can get through both of the exchangers during strenuous exercise and unusually high rates of respiration.
A face mask for use in cold weather to supply warm air for inhalation by normal breathing to persons having respiratory and heart ailments to avoid the discomfort, pain and limited mobility caused by breathing cold air and to healthy people engaged in strenuous cold weather activities. The face mask has inlet and outlet check valves and a cold air intake chamber with an electric heater element therein which heats the cold air to supply warm air for inhalation. The heater element is preferably powered by a portable battery pack and controlled by electronic circuitry to maintain the heated air in a predetermined temperature range.
A lightweight face mask for heating surrounding air to be inhaled by a user includes a thin cup-shaped inner shell and an outer shell spaced from and surrounding the inner shell, the inner and outer shells defining a preheating chamber therebetween through which air passes in a counter-current flow pattern before entering a user breathing space inside the inner shell. The mask may include an electric heating element and battery power supply for additionally heating air entering the user breathing space.
A heating element made of metal mesh through which electric current may be passed to heat fluid passing through the mesh. The mesh is made of intersecting metal wires defining apertures though which the fluid to be heated passes. These apertures are made small enough to cause all the heating to be achieved by conduction and convection. Typical apertures sizes are 40 to 60 .mu.m effective diameter.
