摘要 |
An externally worn tracheal valve has a valve assembly supporting a flexible, resilient lightweight diaphragm centrally thereof. The diaphragm is folded towards the trachea so that air expelled from the trachea will tend to unfold the diaphragm to an extended position to close the valve. During normal breathing the diaphragm remains at least partially folded and the valve remains open. During voice exhalation, the diaphragm extends to close the valve. During high pressure coughing exhalation, the diaphragm may evert, opening the valve to release excessive pressure.
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