Mask with inhalation valve

1. A mask for use in inhaling a substance comprising:

a mask housing defining a chamber and having an inlet and an outlet communicating with said chamber; and

an inhalation valve disposed in said inlet and integrally formed with said mask housing, wherein said valve and said mask housing are formed as a one-piece unit, wherein said inhalation valve is moveable between open and closed positions, and wherein said inhalation valve is positioned entirely exteriorly to said chamber and does not extend into said chamber when positioned in said open and closed positions.

2. The mask of claim 1 wherein said valve is a one-way duckbill valve.

3. The mask of claim 1 wherein said mask housing further comprises an exhaust port, wherein said exhaust port is spaced from said inlet.

4. The mask of claim 3 further comprising an exhalation valve disposed in said exhaust port.

5. The mask of claim 1 wherein said mask housing and said inhalation valve are formed from a single homogeneous piece of material.

6. The mask of claim 1 wherein said inlet comprises a cylindrical tube, wherein said chamber is defined at least in part by a wall, wherein at least a portion of said wall of said chamber flares outwardly from an end of said cylindrical tube, and wherein said inhalation valve is formed entirely within said cylindrical tube and does not extend into said chamber.

7. A mask for use in inhaling a substance comprising:

a mask housing defining a chamber and having an inlet and an outlet communicating with said chamber, said inlet defined by a first tubular wall, wherein said housing further comprises a channel formed around an outer surface of said inlet between said first tubular wall and a second tubular wall, wherein said second tubular wall is formed circumferentially around said first tubular wall in a radially spaced apart relationship therewith; and

an inhalation valve disposed in said inlet and integrally formed with said mask housing, wherein said valve and said mask housing are formed as a one-piece unit.

8. The mask of claim 7 further comprising a holding chamber comprising an outlet tube inserted into said channel.

9. A method of manufacturing an apparatus for delivering a substance to a user, the method comprising:

molding a one-piece mask comprising a mask housing defining a chamber and having an inlet and an outlet communicating with said chamber and an inhalation valve disposed in said inlet and integrally formed with said mask housing, wherein said inhalation valve is moveable between open and closed positions, and wherein said inhalation valve is positioned entirely exteriorly to said chamber and does not extend into said chamber when positioned in said open and closed positions.

10. The method of claim 9 wherein said inhalation valve is a one-way duckbill valve.

11. The method of claim 9 wherein said mask housing further comprises an exhaust port, wherein said exhaust port is spaced from said inlet.

12. The method of claim 11 further comprising disposing an exhalation valve in said exhaust port.

13. The method of claim 9 wherein said one-piece mask is made of silicone.

14. The method of claim 9 wherein said molding said one-piece mask comprises integrally forming said mask housing and said inhalation valve as a single homogeneous piece of material.

15. The method of claim 9 wherein said inlet comprises a cylindrical tube, wherein said chamber is defined at least in part by a wall, wherein at least a portion of said wall of said chamber flares outwardly from an end of said cylindrical tube, and wherein said inhalation valve is formed entirely within said cylindrical tube and does not extend into said chamber.

16. A method of manufacturing an apparatus for delivering a substance to a user, the method comprising:

molding a one-piece mask comprising a mask housing defining a chamber and having an inlet and an outlet communicating with said chamber and an inhalation valve disposed in said inlet and integrally formed with said mask housing, said inlet defined by a first tubular wall, wherein said molding said one-piece mask comprises forming a channel around an outer surface of said inlet between said first tubular wall and a second tubular wall, wherein said second tubular wall is formed circumferentially around said first tubular wall in a radially spaced apart relationship.

17. The method of claim 11 further comprising inserting an output end of a delivery device into said channel.

18. The method of claim 16 further comprising inserting an outlet tube of a holding chamber into said channel.

19. A mask for use in inhaling a substance comprising:

a mask housing defining a chamber and having an inlet tube and an outlet communicating with said chamber;

an inhalation valve disposed in said inlet tube and integrally formed with said mask housing, wherein said valve and said mask housing are formed as a one-piece unit; and

a holding chamber comprising an outlet tube circumferentially disposed around said inlet tube wherein at least a portion of said inhalation valve is disposed in said outlet tube.

20. The mask of claim 19 wherein said holding chamber further comprises a valve seat engaging said inhalation valve when said inhalation valve is in a closed position.

21. A method of manufacturing an apparatus for delivering a substance to a user, the method comprising:

molding a one-piece mask comprising a mask housing defining a chamber and having an inlet tube and an outlet communicating with said chamber and an inhalation valve disposed in said inlet tube and integrally formed with said mask housing; and

inserting an outlet tube of a holding chamber circumferentially around said inlet tube of said mask housing wherein said inhalation valve is disposed in said outlet tube.

22. The method of claim 21 wherein said holding chamber further comprises a valve seat engaging said inhalation valve when said inhalation valve is in a closed position.