US Patent 7793658 Personal assistive breathing apparatus

The present invention relates to a personal use assistive breathing device wherein a can adaptor or bottle mounting member is secured to a bottle canister containing a pressurized gas. A mouth piece member retains an action knob positioned for actuating a stem valve on the bottle canister upon a rotation. During use the action knob is spaced away from the mouthpiece and air passages entrain ambient atmospheric air with the escaping pressurized gas. The action knob may be retained in the in-use position without continual pressure allowing hands-free use. During storage, the action knob is spaced in contact with the mouthpiece prohibiting unintended gas release and enabling ready handling without risk of gas-loss.