This invention relates generally to one-way valves. More particularly, this invention relates to improved one-way valves constructed from flat resilient members bonded in face-to-face relationship.
The term "one-way valve" is intended to mean a device which allows the passage of substances through it in one direction only. Such valves are used in a host of applications, including medical applications, where fluids must be withdrawn from body cavities without reflux to the cavities.
It is most desirable to be able to achieve low "crack" resistance in one-way valves, so that the valves will open in the desired direction of flow on the application of minimal pressure. Similarly, it is most desirable to maximize reflux sensitivity of such valves, so that they will close quickly to prevent back-flow through the valve. It is likewise important that the valves continue to operate when particulate matter becomes lodged in the valves.
In many applications requiring one-way valves, it is important that the valves be compact and flexible, so that they do not occupy excessive space in the devices in which they are employed.
Finally, it is often important that the valves have a long shelf life, so that they will be reliable whenever the devices in which they employed are put to use. In addition, for medical applications, the valves must be constructed from materials approved for use in the treatment of human subjects, and they often must be able to stand up to drastic pressure changes and to a lesser degree to temperature and humidity changes, all as part of sterilization procedures.