Septa

Abstract

A septum includes a disc made of an elastomeric material that is capable of being pierced by a needle and resealing itself when the needle is withdrawn. Embedded in the middle of the disc, from top to bottom, is a ring made of a material that is more rigid than the elastomeric material of the disc. The ring has a center circular opening that is filled by the elastomeric material of the disc. The outer circumference of the ring is greater than the circumference of the disc and extends outwardly beyond the circumference of the disc. The outer part of the ring interacts with the inner screw threads of a cap and supports the septum in the cap. A plurality of additional openings equally spaced about the ring adjacent its outer circumference are also filled with the elastic material of the disc to provide additional support for the septum.

Claims

1. A septum comprising: a disc comprised of an elastomeric material that is capable of being pierced by a needle and resealing itself when the needle is withdrawn, said disc having a thickness and a circumference and a middle portion; a ring made of a material that is more rigid than said elastomeric material and having a thickness less than the thickness of said disc, said ring lying within said disc at substantially the middle of the thickness of said disc, said ring having a center circular opening that has a circumference that is less than the circumference of said disc, said ring having an outer circumference that is greater than the circumference of said disc; said ring including a plurality of additional openings therein adjacent said outer circumference thereof and wherein said elastic material of said disc fills said additional openings, and whereby said ring extends outwardly beyond the circumference of said disc and part of said middle portion of said disc lies within said center opening.

2. The septum as claimed in claim 1 wherein said additional openings are substantially equally spaced around said ring.

3. The septum as claimed in claim 2 wherein said additional openings are round.

4. The septum as claimed in claim 1 wherein said elastomeric material is a chemically inert thermoplastic elastomer.

5. The septum as claimed in claim 4 wherein said ring is made from a material selected from the group consisting of PTFE and polyethylene.

6. The septum as claimed in claim 1 wherein said ring is made from a material selected from the group consisting of PTFE and polyethylene.

7. A septum and bottle cap system comprising: a cap having a top surface and having an opening in said surface, said cap further including an internal thread; a septum, said septum including a disc comprised of an elastomeric material that is capable of being pierced by a needle and resealing itself when the needle is withdrawn, said disc having a thickness and a circumference and a middle portion and a ring made of a material that is more rigid than said elastomeric material and having a thickness less than the thickness of said disc, said ring lying within said disc at substantially the middle of the thickness of said disc, said ring having a center circular opening that has a circumference that is less than the circumference of said disc, said ring having an outer circumference that is greater than the circumference of said disc, said ring extending outwardly beyond the circumference of said disc and part of said middle portion of said disc lying within said center opening, and wherein said septum is located within said cap and wherein at least a portion of said outer circumference of said ring is located within said internal thread of said cap.

8. The septum and bottle cap system as claimed in claim 7 wherein said ring includes a plurality of additional openings therein adjacent said outer circumference thereof and wherein said elastic material of said disc fills said additional openings.

9. The septum and bottle cap system as claimed in claim 8 wherein said additional openings are substantially equally spaced around said ring.

10. The septum and bottle cap system as claimed in claim 9 wherein said additional openings are round.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For the purpose of illustrating the invention, there is shown in the accompanying drawings one form which is presently preferred; it being understood that the invention is not intended to be limited to the precise arrangements and instrumentalities shown.

(2) FIG. 1 is a front top perspective view of a septum showing our new invention;

(3) FIG. 2 is a front elevational view thereof;

(4) FIG. 3 is a cross-sectional view taken through the line 3-3 of FIG. 2;

(5) FIG. 4 is a front top perspective view of a ring that forms a part of the septum of our invention;

(6) FIG. 5 is a front top perspective view illustrating how the septum of our invention is combined with a cap, and

(7) FIG. 6 is a cross-sectional view of the combination of a septum and a cap in accordance with our invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(8) Referring now to the drawings in detail wherein like reference numerals have been used throughout the various figures to designate like elements, there is shown in FIGS. 1-3 a septum constructed in accordance with the principles of the present invention and designated generally as 10. The septum 10 is comprised essentially of two main parts: a disc shaped member 12 and a ring 14.

(9) The disc 12 is made of an elastomeric material that is capable of being pierced by a needle and resealing itself when the needle is withdrawn. It can be made of an injection molded polymer such as Santoprene, a thermoplastic vulcanizate produced by Exxon Mobil, or a more chemically inert thermoplastic elastomer. In the most preferred embodiment, the elastomeric material is a fluorinated thermoplastic elastomer. As can be seen in the figures, the disc has a thickness which is preferably between about 1 mm and about 3 mm although the thickness may vary depending on the use for which the septum 10 is intended. The disc 12 also has a diameter of between about 8 m and 22 mm, again depending on the intended use of the septum. The disc 12 includes the center or middle portion 16 and a circumference 18 surrounding the same.

(10) The ring 14 is made of a material that is more rigid than the elastomeric material of the disc 12. However, it is still somewhat flexible for the reason that will become apparent below. The ring may be made from various materials but is preferably made from PTFE or polyethylene. The thickness of the ring 14 is less than the thickness of the disc 12 and is preferably between about 0.05 mm to about 0.50 mm.

(11) The ring 14 has a center circular opening 20 having a circumference 22 which is less than the circumference 18 of the disc 12. The outer circumference 24 of the ring 14, however, is greater than the circumference 18 of the disc 12. The ring 14 includes a plurality of additional openings therein such as shown at 26, 28, and 30, etc. which are equally spaced around the ring adjacent the outer circumference 24 thereof.

(12) As shown most clearly in FIGS. 1, 3 and 6, the ring 14 is located within the disc 14 at substantially the middle of the thickness of the disc with the outer circumference 24 of the ring 14 extending outwardly beyond the circumference 18 of the disc 12. Preferably, the septum 10 is formed by injection molding the disc 12 around the ring 14. This can be done on a large scale by providing the rings (or at least the inner portions of the rings) on a continuous ribbon, injection molding the elastomeric material around selected areas of the ribbon and then cutting by stamping the outer circumference 24 to form the rings 14. During the injection molding process, the elastomeric material flows into and fills the center circular opening 20 of the ring 14 and all of the additional openings 26, 28 and 30 thereof.

(13) FIGS. 5 and 6 illustrate the manner in which the septum 10 cooperates with a standard cap 32 having internal threads 34. Essentially, the septum 10 is simply pushed upwardly into the open bottom of the cap 32 or the cap is threaded down onto the septum 10. In either case, the exposed portion of the ring 14 that extends beyond the disc 12 engages the threads 34 of the cap 32. As a result, the ring 14 supports the septum 10 in the cap 32 and supports the integrity of the seal between the cap and a bottle or other vessel by preventing the flow of the elastomeric material away from the compression area around the seal.

(14) The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention.