Flexible lid

Technical Field

The invention relates to a closed container for sealing the opening in the flexible cover.

Background Art

Preferably, flexible inner cover for powder for sealing the food container in the form of, for example, by induction heating the flexible inner cover is welded around the opening in the container. Usually such a cover by a layer or multi-layer laminated structure, the laminated structure which comprises aluminum foil and the plastic layer can be welded. For example, when the in order to for aluminum or in order to realize the total thickness of the tearing of the track is used to open the use of a plurality of laminated structure, must be in an appropriate manner is connected with these laminated structure.

Usually, the power along the outside of the cover is connected to the welding path, and, in many applications this is sufficient. However, in some application, obviously, to be welded outside the laminated structure of the route is not in a satisfactory way and hold together.

Content of the invention

The purpose of this invention is to, provide a connection problem can solve the above-mentioned flexible cover. According to Claim 1 through the cover, to realize this purpose. The right on behalf of the request from the favorable mode of execution of the invention, new products and deformation.

The invention relates to a closed container for sealing the opening in the flexible cover, the cover is a main 1st and 2nd main multi-layer structure, wherein at least 1st main layer comprises the aluminum layer and the plastic of the outer layer of the laminated structure can be welded, wherein the outer layer can be welded of the main layer facing the 2nd.

The invention is characterized in that, in the main, thus 1st and 2nd is welded to each other the welding area, wherein the cover comprises a welding region in the centre part 1st, in the 1st part in annular path in welding, wherein annular weld path has at least one interruption part, said interrupting part allows the annular weld in the route in the space and the annular weld path communicating between the outer space.

In order to make the intermediate part of the welding strong enough, a continuous surface needs to be large enough. Therefore, center weld area can not be too small. At the same time it has been found that the, does not allow strong thermal effect of the center region of the same kind of heating to welding temperature. An annular shaped area large enough to allow heating to welding temperature, and not the thermal load becomes too large, and the cover is exposed to uniform heat, and there is no edge effect.

Furthermore, an annular welding the interrupting part in the path of, the restricted to the annular weld path of any possible air could through this annular shape and is spread to its external. In other words, has shown that, if this were not the case, the air will be limited in the path in the annular weld will be small pillow-shaped objects is formed. In a cover of this effect may be difficult to find, however, when the tens of thousands of covers the negotiated price is to be stacked or placed, this may result in non-uniformity and, then, this will make the production interruption. By welding the interrupting part in the path of, usually will not form a pillow-shaped, and, if this trend are still, then flatten the cover. The annular welding by forming a groove in the path, to achieve welding path in the interrupting part.

In the present invention in one embodiment of, along the main welding region includes 1st and 2nd outer edge of the outer edge of extending part of the 2nd of one week. Therefore, in the vast majority of cases, are full of the cover is connected with the can be obtained.

In the present invention in one embodiment of, a main 1st layer 2nd layer, the main 1st 2nd formed to the edge of the main layer. Therefore, for example, can be the prominent edge fold-down, and welding on the inside of the container.

In the present invention in one embodiment of, 2nd main layer including the aluminum layer and the weldable plastic outer layer of the laminated structure, wherein two outside main level outer can be welded each other oriented.

In the present invention in one embodiment of, 1st and 2nd, thus the outer edge of the main layer having a non-circular shape. Therefore, if the annular centre can avoid welding with an external profile similar to the shape of the edge effect will occur.

In the present invention in one embodiment of, annular weld path has two of the above-mentioned types of interrupting part, wherein these two interrupt portion is arranged to be opposite to each other. This can make the air more through.

The invention also relates to a flexible cover of the above-mentioned type of container.

Description of drawings

Will now with reference to the following more detailed description of the invention, wherein:

Figure 1 is a schematic diagram of the cover of this invention the preferred embodiment of the process.

Mode of execution

Figure 1 shows a closed container for sealing and (not shown) of the opening in the flexible cover 1. Cover 1 comprises a 1st main layer 1a and 2nd main layer 1b of the multi-layer structure, thus 1st 1a and 2nd main layer 1b integral cover 1 at the top and bottom, and is welded into a unit. Main layer 1a, 1b are made of the aluminum layer and the weldable plastic layer of the laminated structure, two main levels can be welded to each other.

Main layer 1a, 1b in the weld area is welded to each other, wherein a welding region locate the cover 1 in the region of the center of the 1st 2, in the 1st in annular path in the area of welding, wherein annular weld path are arranged relative to each other the two interruption part 3, this allows the annular weld path 2 with the space of the annular weld path communicating between the outer space. The main 1st welding region 1a and 2nd main layer 1b 2nd compartment extends a week 4, the outer edge of and 5.

1st main layer 1a than 2nd main layer 1b large, the main 1st 2nd formed to the edge of the main layer 6. This edge 6 adapted to fold-down, in and is welded to the container wall around the opening, thereby sealing the container. Appropriately, 1st main layer 1a form the cover 1 on the upper side of the.

As seen, main 1st 1a and 2nd main layer 1b, the outer edge 5, by the cover and 1, is provided with a non-circular shape.

Preferably, interruption part 3 a of the annular circumference of the welding path less than 20%, preferably less than 10%.

The invention is not limited to the above-mentioned embodiment, but can be in the range of the following rights requested change in the definition. For example, main layer contained in the laminated structure may be in a more or less of a layer. Moreover, the number of interruption part may be one or greater than two.

Preferably, cover 1 is provided with a tearing track or pull ring, in order to remove the cover from the container.