Vacuum-drawing lid

1. A lid for sealing a container, comprising:

a base frame including a first valve and a plurality of vertically extending ridges;

a piston including a second valve and a plurality of vertically extending grooves configured to engage with the ridges; and

a chamber bounded at least in part by the base frame and the piston,

the piston movable in a first direction with respect to the base frame to change a volume of the chamber to actuate the first valve, the piston movable in a second direction opposite to the first direction to change the volume of the chamber to actuate the second valve.

2. The lid of claim 1 , wherein the engagement of the grooves with the ridges prevents the piston from rotating with respect to the base frame but allows the piston to translate with respect to the base frame.

3. The lid of claim 1 , further comprising: an inner gasket assembly engaged with and sealed against the base frame and engaged with and sealed against the piston.

4. The lid of claim 1 , further comprising: a bottom gasket that extends around and is sealed against an outer surface of the base frame.

5. A lid for sealing a container, comprising:

a base frame including a first valve;

a piston including a second valve, a main body and a knob protruding radially outward from the main body;

a chamber bounded at least in part by the base frame and the piston;

a cylindrical cam including a hollow body with an inner surface and a groove formed in the inner surface, the knob being positioned in the groove so that rotation of the cylindrical cam causes the piston to move with respect to the base frame to change the volume of the chamber;

the piston movable in a first direction with respect to the base frame to change a volume of the chamber to actuate the first valve, the piston movable in a second direction opposite to the first direction to change the volume of the chamber to actuate the second valve.

6. The lid of claim 5 , wherein the groove is a sinusoidal groove.

7. The lid of claim 5 , further comprising a top cap including a plurality of vertically-extending ridges, the hollow body of the cylindrical cam having an outer surface and including a plurality of vertically-extending grooves in the outer surface, the vertically extending grooves engaged with the vertically-extending ridges.

8. The lid of claim 7 , wherein the engagement of the grooves with the ridges prevents the top cap from rotating with respect to the cylindrical cam.

9. The lid of claim 5 , further comprising a top cap including a plurality of protrusions, the base frame having an outer surface and including a circumferential groove formed in the outer surface, the circumferential groove being engaged with the protrusions.

10. The lid of claim 9 , wherein the engagement of the groove with the protrusions prevents the top cap from translating with respect to the base frame.

11. The lid of claim 5 , further comprising an inner gasket assembly engaged with and sealed against the base frame and engaged with and sealed against the piston.

12. The lid of claim 5 , further comprising a bottom gasket that extends around and is sealed against an outer surface of the base frame.

13. A lid for sealing a container, comprising:

a base frame having a first valve, an outer surface, and a bottom gasket extending around and sealed against the outer surface;

a piston including a second valve; and

a chamber bounded at least in part by the base frame and the piston;

the piston movable in a first direction with respect to the base frame to change a volume of the chamber to actuate the first valve, the piston movable in a second direction opposite to the first direction to change the volume of the chamber to actuate the second valve.

14. The lid of claim 13 , wherein the bottom gasket is configured to engage with and create a seal against an upper rim of the container.

15. The lid of claim 13 , further comprising a bottom gasket that extends around and is sealed against an outer surface of the base frame.