Self-sealing container

Abstract

The self-sealing bag comprises a thin, flexible polyethylene bag having a tapered neck. The bag may include indents in the neck to help hold a filling nozzle. A tapered nozzle is inserted into the tapered neck to fill the bag. An alternative tapered nozzle can have two conduits to permit simultaneous filling and air bleeding. As the bag is filled, the sides expand, and the expanded sides exert pressure on the bag sides at the tapered neck to force the bag sides together and thereby seal the bag.

Description

PRIORITY CLAIM

Applicant claims priority based on U.S. Provisional Application Ser. No. 61/065,945, filed Feb. 15, 2008, titled “Self-Sealing Container” by inventor Michael T. Fusco.

FIELD OF INVENTION

This invention concerns flexible plastic containers or bags that can be sealed without heat seals, welding, adhesives or interlocking sealing members.

BACKGROUND

Bags or containers made from sheets of flexible hydrocarbon polymers, such as low and very low density polyethylene, are well-known and widely used. Such bags frequently are heat sealed or welded on three sides during manufacture, leaving most or all of the fourth side open to permit filling of the bag or container.

Once filled, a user typically wants to seal the bag to prevent the contents from escaping from the bag or container. Ties made of wire, plastic, or paper strips have been twisted or tied to seal plastic bags, but such sealing methods are unsatisfactory for holding liquids, and require an additional step for the user.

Heat seal devices are used where the layers of plastic forming the bag walls are heat sealed to each other by melting the plastic. This method generally provides a satisfactory seal, but requires an expensive heat sealing device, produces surfaces of sufficiently high temperature that can burn the user, and requires an additional step after filling.

Another well-known method of sealing plastic bags or containers uses interlocking ridges of thicker plastic on the interior opposing faces of the opening. The user lines up the ridges and presses the ridges together to seal the bag or container. This seal also is satisfactory for most purposes when sealed properly, but is more expensive than similar plastic bags without the locking seals. Additionally, the ridges frequently are difficult to line up, and frustrate the user, and may not completely seal. These locking ridges require an additional step after filling the bag or container

Other closure means use adhesive between the plastic sheets of the opening, or use mechanical clamps or closures, all of which are more expensive than the bags without such devices, and all of which require an additional step beyond filling the bag or container.

What is needed is an inexpensive plastic bag or container that can be filled and will seal itself without clamps, adhesive or similar known methods of sealing.

What is needed is such a plastic bag or container that can be filled with a fluid and pressurized, and will not leak, even if the bag or container containing fluid is frozen.

What is needed is such a bag or container that can be used without expensive or dangerous equipment.

SUMMARY OF INVENTION

The self-sealing bag comprises a thin, flexible polyethylene bag having a tapered neck. The bag may include indents in the neck to help hold a filling nozzle. A tapered nozzle is inserted into the tapered neck to fill the bag. An alternative tapered nozzle can have two conduits to permit simultaneous filling and air bleeding. As the bag is filled, the sides expand, and the expanded sides exert pressure on the bag sides at the tapered neck to force the bag sides together and thereby seal the bag.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a plan view of the bag;

FIG. 2 shows a perspective view of a tapered nozzle; and

FIG. 3 shows a perspective view of an alternative tapered nozzle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The self-sealing bag 10 shown in FIG. 1 is made of polyethylene using well-known methods to form the bag. Specifically, a rectangular sheet of polyethylene approximately 31.8 millimeters (hereafter “mm”) wide and 439 mm long is folded along a line approximately 223 mm from one end to create the rectangle shown in FIG. 1. The rectangle is then sealed by well-known means along the two sealing lines 11 shown in FIG. 1.

When the rectangle is folded as described, a short tab 12 and a long tab 13 remain above the top sealing flanges 14. The short tab 12 extends approximately 7 mm above the top sealing flanges 14 and the long tab 13 extends approximately 14 mm above the top sealing flanges 14. This difference permits the user to open the bag 10 at the top 15 more easily, since the user can easily separate the short tab 12 and the long tab 13 to reach the tapered neck 24.

The bag 10 has a tapered neck 24 between the top sealing flanges 14 and the body 18. Approximately 13 mm from the top sealing flanges 14, in the direction of the bottom 16, the bag has a pair of indents 19 formed by the sealing lines 11. The indents 19 are v-shaped, and the angle of the ‘v’ as measured from a line 20 perpendicular to the length 21 of the bag 10 towards the top 15 of the bag 10 is approximately 54.6° (the top angle 22, shown in FIG. 1). The bottom angle 23, shown in FIG. 1, measures approximately 48.1°.

The tapered neck 24 extends from the top sealing flanges 14 to the body opening 25. The tapered neck 24 is approximately 12.27 mm wide 26 at the top 15.

The bag 10 also may have holes 27 near the tapered neck 24 which extend through the bag to provide a convenient way to hold the bag 10 in place as it is being filled. The bag 10 can be mounted on posts (not shown) by putting the posts through the holes 27.

The bag 10 is filled using a tapered nozzle 28, sized to match the tapered neck 24, so that the tapered neck 24 is pushed onto the tapered nozzle 28, and so the tapered neck fits snuggly and will not allow the filling material 34 to leak out of the tapered neck in the direction of the top 15 of the bag 10. The fit between the tapered neck 24 and the tapered nozzle 28 is improved if the tapered nozzle 28 includes a ridge 29 sized to fit the indents 19. As the ridge 29 is pushed into the indents 19, a seal similar to an “o” ring is formed. The length of the tapered nozzle relative to the tapered neck is very important. If the tapered nozzle is too short, it will cause the tapered neck to seal off between the end of the tapered nozzle 28 and the body opening 25. If the tapered nozzle is too long, it will enter the body opening 25 and the tapered neck 24 will not seal when the tapered nozzle 28 is removed. It is preferable if the tapered nozzle 28 is inserted into the tapered neck 24 approximately 85% of the length of the tapered neck 24.

In an alternative embodiment shown in FIG. 3, the tapered nozzle 28 preferably has two conduits, a filling conduit 30 and a bleeding conduit 31, as shown in FIG. 2. This alternative is not necessary for most bags, since they contain very little air when first filled. The filling conduit 30 allows liquid or fluid or other material (collectively “filling material” 34) used to fill the bag to flow into and fill the body 18. As the filling material 34 flows into the bag, air bleeds from the bag through the bleeding conduit 31, and out of the bleeding conduit through an air bleeder vent 32. The bleeding conduit 31 is not in fluid communication with the filling material reservoir 33, but the filling conduit 30 is in fluid communication with the filling material reservoir 33 to permit filling material 34 to flow from the filling material reservoir 33, through the filling conduit 30 and into the body 18.

The bag 10 shown in FIG. 2 lacks a short tab 12 and a long tab 13 to show the filling and vent features more clearly.

As the filling material 34 is placed in the bag 10 through the filling conduit 30, and air bleeds from the body 18 through the bleeding conduit 31, the bag expands. When the body 18 is full, the user removes the bag 10 from the tapered nozzle 28. The expanded body 18 exerts a pressure on the bag 10 in the region of the tapered neck 24 between the body opening 25 and the sealing lines 11. This pressure is sufficient to retain the filling material 34 in the body 18, even while the filling material is being frozen.

The method of filling the bag 10 comprises the steps of opening the bag 10 at the top 15; inserting the tapered nozzle 28 into the tapered neck 24; filling the body 18 with filling material 34 and removing the bag 10 from the tapered nozzle 28. If the tapered nozzle 28 includes a ridge 29, and the bag 10 includes indents 19, the tapered nozzle 28 is inserted into the tapered neck 24 until the ridge 29 seats in the indents 19.

The tapered nozzle 28 can be placed in the tapered neck 24 by moving the tapered nozzle 28 relative to the tapered neck 24, or vice versa.

The bag 10 can be filled using a pressurized filling material reservoir 33. The pressurizing could arise from something as simple as a flexible bottle that is squeezed by the user, or from hand or electrically operated pumps.

In one application of the bag, a sweet syrup is placed in the filling material reservoir 33, a bag 10 is placed on a fixed tapered nozzle 28, and a hand pump is pumped to force the syrup into the bag. After filling, the bag 10 is frozen to create a frozen treat for human consumption.

Although the present invention has been described in terms of certain preferred embodiments, other embodiments will become apparent to those of skill in the art with reference to the disclosure contained herein. Accordingly, the scope of the present invention is intended not to be limited by the disclosed embodiments, but to be coextensive with the full scope of the attached claims.

Claims

1. A self-sealing container comprising a body having a body opening, a tapered neck, and two top sealing flanges, so that when fluid is placed in the bag, the bag expands, exerting sufficient pressure in the tapered neck to close the tapered neck and retain the fluid in the body.