초록 ▼

The present invention provides a vent assembly suitable for use with a respiratory mask of the type used in CPAP treatment. In one embodiment the vent is made of a thin air permeable membrane. Generally, the membrane is thinner than 0.5 mm. The membrane can be made of a hydrophobic material such as

The present invention provides a vent assembly suitable for use with a respiratory mask of the type used in CPAP treatment. In one embodiment the vent is made of a thin air permeable membrane. Generally, the membrane is thinner than 0.5 mm. The membrane can be made of a hydrophobic material such as polytetrafluoroethylene (PTFE). The membrane can also be fabricated from expanded PTFE. The expanded PTFE membrane is mounted on a polypropylene scrim. The pores of the membrane have a reference pore size of 10 to 15 microns. In an alternative embodiment, the vent assembly includes a vent constructed from stainless steel. In another embodiment the membrane has a superficial cross-sectional area of approximately 500 mm2. In another embodiment the vent assembly comprises a membrane attached to a vent frame, the vent assembly forming an insert which can be removeably attached to a mask fame.

대표청구항 ▼

1. A respiratory mask comprising: a mask shell that can be fitted over a user's nose; a cushion positioned in proximity to an edge portion of the mask shell to aid in fitting the mask shell to a user's face; a breathable gas inlet that can conduct gas through the mask shell to a breathing cavit

1. A respiratory mask comprising: a mask shell that can be fitted over a user's nose; a cushion positioned in proximity to an edge portion of the mask shell to aid in fitting the mask shell to a user's face; a breathable gas inlet that can conduct gas through the mask shell to a breathing cavity formed between the mask shell and a user's face when the mask is in use; and a gas washout vent made from a thin air permeable membrane formed, constructed and arranged to allow gas to exit from the breathing cavity, wherein the membrane includes a plurality of tapered holes. 2. A respiratory mask according to claim 1, wherein each of the tapered holes includes a small end facing atmosphere. 3. A respiratory mask according to claim 1, wherein each of the tapered holes includes a small end facing an interior of the mask shell. 4. A respiratory mask according to claim 1, wherein the membrane is mounted in an insert that is selectably detachable from the mask shell. 5. A respiratory mask according to claim 1, wherein a thickness of the membrane is less than a thickness of the mask shell. 6. A respiratory mask comprising: a mask shell that can be fitted over a user's nose; a cushion positioned in proximity to an edge portion of the mask shell to aid in fitting the mask shell to a user's face; a breathable gas inlet that can conduct gas through the mask shell to a breathing cavity formed between the mask shell and a user's face when the mask is in use; and a gas washout vent made from a thin air permeable membrane formed, constructed and arranged to allow gas to exit from the breathing cavity, wherein the membrane is formed in an opening of the respiratory mask, and a cross piece is formed across the opening. 7. A respiratory mask comprising: a mask shell fittable over a user's nose; a cushion positioned in proximity to an edge portion of the mask shell to aid in fitting the mask shell to a user's face; a breathable gas inlet to conduct gas through the mask shell to a breathing cavity formed between the mask shell and the user's face when the mask is in use; and a gas washout vent including an air permeable member to allow gas to exit from the breathing cavity, wherein the member comprises a stainless steel sheet having a thickness of less than about 0.5 mm, the stainless steel sheet includes a plurality of holes, an area of the holes is substantially 5% of a total superficial surface area of the stainless steel sheet, a diameter of each of the holes is less than 0.2 mm, a total open area of the holes is approximately 1-25% of the superficial surface area of the stainless steel sheet, and an area of the stainless steel sheet is about 322 mm2. 8. A respiratory mask comprising: a mask shell fittable over a user's nose; a cushion positioned in proximity to an edge portion of the mask shell to aid in fitting the mask shell to a user's face; a breathable gas inlet to conduct gas through the mask shell to a breathing cavity formed between the mask shell and the user's face when the mask is in use; and a gas washout vent including an air permeable member to allow gas to exit from the breathing cavity, wherein the member comprises an expanded polytetrafluoroethylene sheet having a thickness of about 0.05 mm, the sheet includes a plurality of pores in the range of 10-15 microns, an area of the sheet is approximately 480 mm2,a bubble point of the sheet is at least 0.02 bar, and an airflow capacity of the sheet is about 0.37 LPM/cm2.