Container seal with flexible central panel

1. A seal removably mountable to the rim of a container, said seal comprising a substantially rigid peripheral mounting ring and a flexible central panel, said mounting ring being of a fixed predetermined shape-sustaining configuration surrounding said central panel, said flexible central panel at rest being generally in a plane defined by said ring and having a peripheral edge portion bonded to said ring, a non-bonded portion of said central panel being flexibly deformable laterally and in opposite directions independently of and relative to said ring to define variations in the effective height of the central panel both above and below said mounting ring relative to a single underlying container.

2. The seal of claim 1 wherein said central panel is elastically deformable.

3. The seal of claim 2 wherein said central panel is flexibly deformable independently of said mounting ring and with said mounting ring maintained in said predetermined configuration.

4. The seal of claim 3 wherein said mounting ring includes an upright wall adapted to surround and engage a container rim, a ring flange integral with and extending inward relative to said wall and adapted to overlie and extend inwardly relative to an underlying container rim, said flange defining an inner peripheral edge, said peripheral edge portion of said central panel peripherally overlapping and being bonded to said flange, said central panel being flexible relative to said flange inward of said flange inner peripheral edge.

5. The seal of claim 4 wherein said central panel, at said flange, includes an abutment engaged against and bonded to said flange inner peripheral edge.

6. The seal of claim 4 wherein said central panel includes spaced concentric undulations therein to enhance flexibility and the degree of flexible deformation.

7. The seal of claim 6 wherein said central panel includes a central area defining a position for the application of a downwardly deforming pressure to said central panel, and a rigid disc overlying and bonded to said central area for equalization of applied pressure to said central panel.

8. The seal of claim 6 wherein said undulations comprise corrugations with substantially equal height ridges and valleys.

9. The seal of claim 6 wherein said undulations comprise low profile ridges each with a cross-sectional thickness narrowing toward opposed edges thereof and defined valleys therebetween.

10. The seal of claim 9 wherein said valleys defined between said ridges are each of a cross-sectional thickness less than the cross-sectional thicknesses of the ridges to each side thereof.

11. The seal of claim 4 wherein said peripheral edge portion of said central panel underlies said flange and extends to and along said wall, bald peripheral edge portion being bonded to both said flange and said wall and adapted to lie between and provide enhanced sealing between said mounting ring and the rim of a container to which the ring is mounted.

12. The seal of claim 3 wherein said central panel includes a central area defining a position for the application of a downwardly deforming pressure to said central panel, and a rigid disc overlying and bonded to said central area for equalization of applied pressure to said central panel.

13. A seal adapted to mount to the rim of a container for varying the internal head space in the container, said seal comprising a flexible central panel and a substantially rigid peripheral mounting ring surrounding said central panel, said central panel having a peripheral edge portion peripherally bonded to said ring, said central panel being laterally flexible and positionable relative to said ring both above and below said ring and to the rim of a single underlying container to thereby vary the head space within the underlying container.

14. The seal of claim 13 wherein said substantially rigid mounting ring includes an upper flange projecting radially inward and defining a plane overlying a container rim receiving said seal with said flange extending inward of the container rim, said peripheral edge portion of said central panel overlapping and being bonded to said flange, said central panel, inward of said flange being generally in said plane and flexing independently of and without distortion of said flange and mounting ring.

15. The seal of claim 14 including a series of generally concentric undulations defined in said flexible central panel for enhancing the flexibility and range of movement of said central panel.

16. The seal of claim 15 wherein said central panel includes a central area defining a position for the application of a downwardly deforming pressure to said central panel, and a rigid disc overlying and bonded to said central area for equalization of applied pressure to said central panel.

17. The seal of claim 13 wherein said mounting ring includes means for sealing said seal peripherally to and about a container rim.

18. In combination with a substantially rigid open-mouth container having a peripheral rim defining said mouth, a seal, said seal including an outer peripheral substantially rigid mounting ring releasably sealable to said container rim, a flexible central panel bonded peripherally to said ring to overlie the mouth of the container, a non-bonded portion of said central panel being flexible relative to said container rim and independent of said substantially rigid mounting ring, said panel laterally flexing outward relative to said container rim to enlarge container head space and accommodate an overfilled condition in said container, said panel laterally flexing inward relative to said container rim to reduce container head space in an underfilled container, and said flexing outward and said flexing inward being relative to a single said open-mouth container.

19. The combination of seal and container of claim 18 wherein said central panel is flexibly resilient and, when flexed inward, creates a partial vacuum in said container with said central panel retained inwardly flexed by said partial vacuum to maintain a reduced head space.

20. The combination seal and container of claim 19 including a series of generally concentric undulations defined in said flexible central panel for enhancing the flexibility and range of movement of said central panel.

21. The seal of claim 1 wherein said substantially rigid peripheral mounting ring has an annular shape and configuration.

22. The seal of claim 1 wherein said wherein said substantially rigid peripheral mounting ring has a rectangular shape and configuration.

23. The seal of claim 1 wherein said wherein said substantially rigid peripheral mounting ring has a square shape and configuration.

24. The seal of claim 1 wherein said wherein said substantially rigid peripheral mounting ring has an oval shape and configuration.

25. The combination of seal and container of claim 18 wherein said substantially rigid peripheral mounting ring has an annular shape and configuration.

26. The combination of seal and container of claim 18 wherein said substantially rigid peripheral mounting ring has a rectangular shape and configuration.

27. The combination of seal and container of claim 18 wherein said substantially rigid peripheral mounting ring has a square shape and configuration.

28. The combination of seal and container of claim 18 wherein said substantially rigid peripheral mounting ring has an oval shape and configuration.