Portable, cryogenic gas delivery apparatus

A portable, liquid oxygen system for delivering oxygen gas to a user, the system comprising:

• a container sufficiently insulated from the ambient to hold oxygen in the form of both liquid oxygen and oxygen gas, the container characterized by a range of evaporation rates at which the liquid oxygen is evaporated within the container to become the oxygen gas;
• a fill system configured to fill the container only partially with the liquid oxygen to define a volume of liquid oxygen therein and a volume of pressurized oxygen gas therein;
• a delivery system having an inlet connected to the volume of oxygen gas for receiving the oxygen gas from the container, and an outlet for connecting to the user to deliver the oxygen gas;
• a thermo-pneumatic regulator adapted to detect variations in the pressure of the volume of the oxygen gas, and to increase the evaporation rate in response to the detection of a predetermined drop in pressure of the volume of the oxygen gas, and to decrease the evaporation rate in response to the detection of a predetermined increase in pressure of the volume of the oxygen gas, whereby the regulator regulates the pressure of the volume of the oxygen gas to remain within a selected baseline pressure range;
• wherein the regulator is adapted to charge the delivery system with the oxygen gas in sufficient amounts to fulfill the user's breathing needs as the liquid oxygen is evaporated within the container.

A method of charging a portable liquid oxygen system, comprising the steps of:

• providing an insulated container with a vent for discharging excess oxygen and a passage in communication with the vent, the passage having an opening at a location spaced from the inner wall of the container;
• initiating the filling of the container with oxygen from a supply of liquid oxygen under pressure by connecting the container to the supply;
• continuing the filling process to fill the volume available in the container only partially with liquid oxygen, the filling process continuing until the volume of the liquid oxygen in the container reaches a level high enough so that the liquid oxygen enters the opening of the passage and exits the vent in a fashion discernable to the user charging the system;
• and
• disconnecting the container from the supply once the liquid oxygen is discerned to be exiting from the vent, whereby the container is charged with the partial amount of the liquid oxygen resulting from the filling process.

A method of dispensing oxygen gas from a liquid oxygen system, comprising the steps of:

• providing an insulated container with a chamber adapted to be only partly filled with oxygen in the liquid phase, thereby creating a liquid oxygen volume and a volume of oxygen gas in the chamber;
• maintaining the volume of the oxygen gas at pressures above ambient;
• dispensing a sustained, breathable supply of the oxygen gas to a recipient through a passage in communication with the volume of the oxygen gas;
• wherein the step of dispensing the oxygen including receiving the oxygen gas through the passage irrespective of the orientation of the chamber.

A portable liquid oxygen system for delivering gaseous oxygen to a user, the system comprising:

• a container sufficiently insulated from the thermal energy of the ambient to hold oxygen in both the liquid phase and the gas phase inside the container;
• a delivery system having an inlet for receiving the oxygen in the gas phase from the container, an outlet for connecting to the user to deliver the gaseous oxygen, and a conserver connected between the inlet and the outlet and operable in response to inhalation to deliver the gas to the user;
• and
• a thermo-pneumatic regulator secured to the container to vary the amount of thermal energy transferred to the container in response to variations in the pressure of the gaseous oxygen in the container.

A method of charging a liquid oxygen system, comprising the steps of:

• providing an insulated container with a vent for discharging excess oxygen and a passage in communication with the vent, the passage having an opening at a location spaced from the inner wall of the container;
• initiating the filling of the container with oxygen from a supply of liquid oxygen under pressure by connecting the container to the supply;
• continuing the filling process to fill the volume available in the container only partially with liquid oxygen, the filling process continuing until the volume of the liquid oxygen in the container reaches a level high enough so that the liquid oxygen enters the opening of the passage and exits the vent in a fashion discernable to the user charging the system;
• and
• disconnecting the container from the supply once the liquid oxygen is discerned to be exiting from the vent, whereby the container is charged with the partial amount of the liquid oxygen resulting from the filling process;
• wherein the opening is substantially in the middle of the volume defined by the insulated container, and further comprising the step of continuing the filling process until the volume of the container is about 50% filled with the liquid oxygen.

A method of charging a portable liquid oxygen system, comprising the steps of:

• providing an insulated container with a vent for discharging excess oxygen and a passage in communication with the vent, the passage having an opening at a location spaced from the inner wall of the container;
• initiating the filling of the container with oxygen from a supply of liquid oxygen under pressure by connecting the container to the supply;
• continuing the filling process to fill the volume available in the container only partially with liquid oxygen, the filling process continuing until the volume of the liquid oxygen in the container reaches a level high enough so that the liquid oxygen enters the opening of the passage and exits the vent in a fashion discernable to the user charging the system;
• disconnecting the container from the supply once the liquid oxygen is discerned to be exiting from the vent, whereby the container is charged with the partial amount of the liquid oxygen resulting from the filling process;
• and
• introducing thermal energy from the ambient into the container by means of a thermally conductive path, the path exposed on one end to the temperature of the ambient and on another end to the volume defined by the insulated container, the introduction of thermal energy being sufficient to increase the pressure within the insulated container to an operational, baseline pressure.

A method of dispensing oxygen gas from a liquid oxygen system, comprising the steps of:

• providing an insulated container with a chamber adapted to be only partly filled with oxygen in the liquid phase, thereby creating a liquid oxygen volume and a volume of oxygen gas in the chamber;
• maintaining the volume of the oxygen gas at pressures above ambient;
• dispensing a sustained, breathable supply of the oxygen gas to a recipient through a passage in communication with the volume of the oxygen gas;
• wherein the step of dispensing the oxygen including receiving the oxygen gas through the passage irrespective of the orientation of the chamber;
• introducing thermal energy into the insulated container through a heat conductive path between the ambient and the chamber, wherein the step of introducing thermal energy further includes increasing the evaporation rate in response to a decrease in the pressure of the volume of gas and decreasing the evaporation rate in response to an increase in the pressure of the volume of gas.