A medical respirator in which gas is stored and passed to a patient in an adjustable predetermined time having switch means to control the flow of gas from a pressure source into a variable volume during the expiration period of the respirator and from the variable volume to the patient through restrictive means during inspiration period. The gas container is divided into two volumes separated by a movable member. Gas for the patient is expelled from the first volume, which is variable, by decrease of the first volume caused by movement of the movable member as a result of patient gas pressure in the second volume.
A volume-limited general medical respirator is controlled by an integrated fluidic circuit. The respirator includes various alarm systems, control valving and main exhalation and inhalation phases operated entirely through gas means. A collapsible bellows is utilized to inspire the patient and is powered by an operative gas such as oxygen. The same operative gas not only powers the bellows during inspiration of the patient but is then recycled during the exhalation phase and thereafter used in the system for introduction to the patient during the subsequent inspiration phase.
A portable power-driven respirator controls measured amounts of air (and, if desired, admix gases, such as oxygen) to a patient during inhalation events and from the patient during exhalation events. The events are controlled pneumatically and electrically as to time and rate of occurrence, duration and relationship. Quantities, pressures and times are precisely regulated and monitored automatically with some patient override, provision for deep breaths, some manual control and with indicators and alarms. The alarms include plural inspiratory pressure alarms, some momentary without necessary continuation, and with provision to terminate inhalation under certain conditions and to put the patient effort on an adjustable pressure level with an optional decreasing inspiratory flow pattern available and with auxiliary equipment separately supplied with air so as not to interfere with the operation of the respirator itself.
A first-stage air regulator for diving apparatus which is designed to reduce high tank air pressures to air pressures more compatible with normal breathing. The air regulator includes a cylindrical regulator housing containing a sliding piston which is provided with air slots adapted for transiently establishing air flow from a high-pressure air chamber contained in one end of the housing to an intermediate-pressure air chamber adjacent to the high-pressure air chamber. The air within the intermediate-pressure chamber equilibrates with pressure applied to the piston by a spring and ambient water pressure, before passing to a second-stage air regulator and mouthpiece by means of an air hose. Additionally, air can be transferred from the intermediate-pressure chamber to accessories such as a lift bag, a power inflator or a blow gun, through corresponding air hoses.
4036221 - Respirator - Owned by Sutter Hospitals Medical Research Foundation (Sacramento, CA)
A volume-cycled respirator including a piston driven by a translational motor in a feedback control system for forcing a controlled volume of gas into the lungs of a patient throughout each inspiratory cycle. A waveform generator produces a volume-versus-time waveform representing the desired volume of gas to be delivered to the patient throughout each inspiratory cycle. The feedback loop includes a position transducer responsive to the changing position of the piston for producing a volume-versus-time waveform representing the actual volume of gas delivered to the patient throughout each inspiratory cycle. The desired waveform is compared with the actual waveform to produce an error signal which drives the translational motor so it forces the piston travel waveform to follow the desired waveform.
