| 摘要 |
<p>A gas vent valve assembly may be attached or incorporated to a disposable fluid transfer set used with a fluid warmer to administer an infusate to a patient. The gas vent valve assembly has a housing having a fluid inlet, a gas outlet and a fluid outlet. The gas outlet is located at the top of the housing while the fluid outlet is located at the bottom of the housing. The fluid inlet is located at a side lower portion of the housing. Inside the housing is an actuator float that has an upper seal and a lower seal. The dimension of the float relative to the chamber of the housing is such that the float is freely movable within the housing to an upper position whereby its upper seal closes the gas outlet while the fluid outlet is opened, and to a lower position whereby its lower seal closes the fluid outlet and the gas outlet is opened. The movement of the float is dependent on the respective amounts of air and fluid in the housing, and the buoyancy of the float relative to the fluid in the housing. When a predetermined volume of air gets inside the housing, the float sinks to its lower position to close the fluid outlet and open the gas outlet, so that the air inside the housing is vented to atmosphere while fluid is prevented from being output to the patient. When the amount of gas in the chamber has been reduced to a given volume, with a corresponding increase in the amount of fluid in the housing, the float is raised to open the fluid outlet, thereby enabling the fluid inside the housing to be output to the patient. At that time, the gas outlet is shut to prevent any reverse inflow of air into the housing.</p> |
