| 摘要 |
A respirator mask has a valve 11 for admitting breathing gas and a pressure chamber 8 between a breathing space 9 in front of the user's respiratory organs and the surrounding atmosphere. The purpose is to set up a gauge pressure in front of the user's respiratory organs during the inhalation phase as well as during the exhalation phase. Pressure chamber 8 is defined by two dish-shaped ports 12, 13 (port 12 being connected by holes 14 to space 9) and by a diaphragm 7. Port 13 is forced downwards by a spring 19. When the user inhales, pressure chamber 8 moves downward under the action of spring 19 and diaphragm 7 and pivots an arm 28 which causes the valve 11 to open. When the user exhales, pressure chamber 8 moves upwards and closes valve 11, port 12 abuts against flange 18, and port 13 is forced further upwards against spring 19 to allow gas to escape to the outside. A detent unit 31 may be present to push pressure chamber 8 upwards and keep valve 11 closed. <IMAGE> |
