Method and apparatus for controlling gas flow from cylinders

A device for controlling the flow of a gas from a gas cylinder, comprising:

• a gas flow passageway through the device and having an inlet and an outlet, wherein the inlet is configured to be sealingly attached to the gas cylinder to receive the gas from the gas cylinder;
• a gas flow valve disposed in the passageway and capable of controllably closing or opening the passageway to the flow of gas therethrough;
• a shroud configured for surrounding the gas flow valve and protecting the gas flow valve against damage;
• a manually operable selector operatively connected to the valve to enable adjustment of the position of the valve to a closed position and one or more open positions by movement of the selector;
• a pressure sensor capable of detecting the pressure of the gas in the gas cylinder when the device is sealingly attached to the gas cylinder and further capable of generating an electronic signal corresponding to the detected pressure;
• an electronic display capable of displaying information in digital and/or analog form;
• an electronic alarm capable of being actuated to signify the presence of an alarm state audibly, visibly, or both audibly and visibly during the administering of the gas from the gas cylinder, the electronic alarm further capable of being deactivated during a gas cylinder fill process and reactivated upon refilling of the gas cylinder with the gas;
• and
• electronic control connected to the gas flow control, the pressure sensor, the electronic display, and the alarm, which is capable of detecting the position setting of the valve, detecting from the pressure sensor at periodic predetermined time frequencies the pressure of the gas in the gas cylinder, calculating as a function of the detected position setting and the detected periodic pressures the interval of time remaining until the amount of gas in the gas cylinder will reach a predetermined lower threshold, generating one or more signals causing the display to concurrently display the interval of time remaining and the detected pressure;
• the electronic control further configured to generate a signal actuating the electronic alarm when the amount of gas in the gas cylinder reaches the preset pressure threshold during the administering of the gas from the gas cylinder;
• wherein the electronic control, electronic alarm and the electronic display are powered by a rechargeable battery disposed within the shroud.