| 摘要 |
A tracheostoma valve adapted to control the flow of air through a tracheostoma comprises a tubular housing (10) having an open first end to be connected to the tracheostoma, and forming at least one side opening (18) in the wall (17) thereof, a shut-off valve member (19), and a normally closed cough valve member (26). The shut-off valve member comprises a flexible diaphragm mounted in the housing and shaped to normally assume a curled position spaced from the inside surface of the housing wall to allow air flow through the housing and the side opening from trachea to the ambient atmosphere, and to engage said surface, closing the side opening, at a predetermined air flow rate. The cough valve member controls an open second end of the housing to open in response to a particular pressure achieved in the housing and to close automatically at reduction of the air pressure. |
