The present invention relates to a closing de¬ vice for containers, particularly for bottles, corrt- prising an elastic body to be positioned in the opening of the container, the elastic body being arranged to be positioned tightly against the inside of the opening, whereby a flexible pulling means of a thin material is provided in connection with the elastic body in such a way that when in use it is positioned against the lower portion of the elastic body and projects from the opening of the container.

Bottles and other containers are closed by means of various closing devices the structure and operation of which vary with the application" in question. A crown cap of metal is probably the most widely used type of closing device with soft drinks and beer, which set high requirements on the closing device both qualitatively and quantitatively. The crown cap still holds a strong position on the market in spite of the introduction of various less expens¬ ive closing devices. A common feature of such com¬ peting closing devices is that they do not require a separate opener. In certain cases, they can be re- used. Even though some of these competing closing de¬ vices offer both of the above-mentioned major advantages, they have not been able to surpass the crown cup, which has been used for several decades. This is because it has not been possible previously to manufacture a closing device which would be equal¬ ly suitable for automatic closing of bottles as the crown cap and which could compete in costs with the crown cap.

Closing devices made of thin metal foil and comprising a tab of metal which is pulled in a pre-

determined direction to open the bottle without any separate opener have certain disadvantages on account of which they have not become predominant. Above all, they do not operate reliably and may easily damage the hands.

Closing devices to be screwed on are becoming more and more popular; however, machines that close bottles with spiral caps are complicated and expensive. In addition, the neck of the bottle has to be provided with threads for the spiral caps, which increases the manufacturing costs of the bottle.

The traditional way of closing a container with a stopper usually made of an elastic material is still used widely with wine bottles, for instance. The stopper.- is thereby usually made of cork. A draw¬ back of this closing device is that it has to be opened with a cork screw. Furthermore, it is expensive to manufacture and the closing of the bottle is complicated: the cork has to be dampened and heated to make it sufficiently elastic for inser¬ tion into the op ^' ening of the bottle. A major advan¬ tage of this kind of cork, however, is that it allows "breathing", that is, allows very small amounts of air to enter the bottle, which is important for wines which are stored for long periods of time.

U.S. Patent Specification 4,613,043 discloses a closing device comprising a conventional cylindrical cork which is inserted into the opening of the bottle. To avoid the use of a cork screw when opening the bottle, a band is positioned under and along the sides of the cork in such a way that it projects from the opening of the bottle when the cork is posi¬ tioned in place. A drawback of this previously known closing device is that the cylindrical cork is dif- ficult to open: a great force has to be applied to

open it because of the large friction surface of the cork against the opening of the bottle. The band sur¬ rounding the cork is easily damaged when it is pulled with great force. Furthermore, it is unpleasant to pull a thin band violently with bare hands. If the thickness of the band is increased to improve its strength so that it would better resist the pulling, points of discontinuity are formed between the cork and the edges of the band, which substantially deteriorate the sealing effect of the closing device.

The object of the present invention is to provide a closing device which avoids or at least substantially alleviates all the above-mentioned drawbacks. To achieve this object, the closing device of the invention is characterized in that the elastic body is formed by a substantially ball-shaped body. As the elastic body is ball-shaped, it can be pulled out of the opening of the bottle by a "rolling" move¬ ment, which decisively reduces the force required for opening the closing device. Another advantage of the ball shape is that the closing device can be very easily placed in position by means of an automatic machine without any narrow tolerances between the machine and the opening of the bottle. The present invention is based on the idea that the cylindrical opening of the container is closed by means of a ball-shaped body which is lifted up by means a thin filmlike auxiliary means when the con¬ tainer is opened. The friction surface of a ball- shaped body against the opening of the bottle is small, which is of vital importance for the oper- ability of the closing device.

One major advantage of the closing device of the invention is that it enables the container to be opened easily without any separate opener. Another

advantage is that the container can be closed tightly and easily by machine or by hands, several times, if required. Still another advantage is that the closing device is easy to manufacture and the opening of the container can be of any shape. Finally, an advantage of the ball-shaped elastic body is that it can be surrounded with a coating in such a way that the creasing of the coating is minimized, which improves the sealing effect of the closing device. In the following the invention will be de¬ scribed in greater detail by means of its two pre¬ ferred embodiments with reference to the attached drawings, in which

Figure 1 shows one embodiment of the closing device when fitted in a bottle;

Figure 2 is a top view of the closing device of Figure 1,

Figures 3 to 5 are a side, top and bottom view, respectively, of the closing device shown in Figures 1 and 2,

Figure 6 illustrates the manufacture of the closing device;

Figure 7 shows another embodiment of the closing device when fitted in a conventional soft drink or beer bottle;

Figure 8 is a top view of the closing device of Figure 7;

Figures 9 to 11 are a side, top and bottom view, respectively, of the closing device of Figures 7 and 8.

The closing device shown in Figures 1 and 2 comprises an elastic body 1 fitted in the neck por¬ tion of a bottle. In a free state the elastic body 1 is ball-shaped. When fitted in the neck portion of the bottle, it bears lightly and steadily against the

inside of the neck, being thus oval in shape. In the first embodiment of the closing device, a thin flex¬ ible plastic strip 2 is positioned under the elastic body 1. The middle portion of the strip 2 is posi- tioned against the elastic body while its both end portions 3, 4 project from the opening of the bottle neck. One end portion 3 of the strip 2 is positioned against the outside of the bottle neck while the other end portio is left free to enable the bottle to be opened by gripping the free end portion. The end portion 4 thus forms a tab which can be gripped by fingers. By pulling the end portion 4 outwards, the ball-shaped body is displaced by a rolling move¬ ment upwards and out of the opening of the bottle neck, so that the bottle is opened and ready to be emptied. Due to the rolling movement of the body 1 the force required for opening the bottle is relatively small even in cases where the closing de¬ vice has to resist a high pressure prevailing inside the bottle, for instance, when the bottle with filled with carbonated beverage. During the opening step, one end portion, that is, the strip portion 3 is positioned against the bottle neck. Therefore the end portions 3, 4 of the pull strip 2 are provided with an adhesive material which ensures a good grip on the end portion 4 when the bottle is opened.

Figure 3 shows the closing device of Figures 1 and 2 from the side in a free state. It appears from the figure that the pull strip 2 is attached in the middle to the ball-shaped elastic body 1 by means of glue, for instance. As the middle portion of the pull strip 2 is attached to the elastic body 1, the closing device is easier to handle both when closing and when opening the bottle, whereby the elastic body is kept properly in position.

Figure 4 is a top view and Figure 5 a bottom view of the closing device.

As can be seen from Figure 5, the end portions of the pull strip 2 are provided with an adhesive material 5 to fasten the strip along the surface of the bottle, with the exception of the outermost edges 7 of the end portions which are to be gripped with finger nails.

Figure 6 illustrates the manufacture of the pull strip 2 shown in Figure 2, for instance, in an inexpensive and efficient way by cutting a plastic band 6 in the transverse direction. The plastic band can be easily coated with the adhesive material 5. '

Figure 7 shows another embodiment of the closing device. In this embodiment, the closing de¬ vice comprises an elastic body 1 ' of the type shown in Figures 1 to 5, for instance, while the pulling means is formed by a coating 2' surrounding the ball- shaped body 1 ' . As the coating 2 ' surrounds the ball- shaped body 1' on all sides, the bottle will be closed completely tightly even in cases where the thickness -of the coating is great. This arrangement has the advantage that the strength of the coating is sufficient for pulling out the elastic body in all applications.

Figure 8 is a top view of the closing device of Figure 7.

Figure 9 shows the closing device of Figures 7 and 8 from the side when in a free unloaded state. As appears from the figure, the elastic ball-shaped body 1 ' is surrounded with the coating 2' comprising two films 2a' and 2b' positioned against each other. The films 2a' and 2b' are circular in shape and prefer¬ ably made of plastic. Figure 10 is a top view of the closing device of Figure 9. Figure 11 is a bottom

view of the closing device of Figure 9. As appears from Figure.11, the peripheral area of the lower film 2b' is provided with an adhesive material 5b'. The purpose of this adhesive surface 5b' is the same as that of the surface 5 in the first embodiment of the invention. The central area of the lower film is not provided with an adhesive surface since this would prevent easy insertion of the closing device into the opening of the bottle. The entire lower surface of the upper film 2a' shown in Figure 10 is covered with the adhesive material so that the upper film 2a' adheres to the lower film 2b' . The adhesive material also centers the elastic body 1' between the films 2a' and 2b' . The ball-shaped body 1, 1' is made of a material which is deformable so that the diameter of the body can be decreased by 5 to 25%, preferably by 10 to 20%. Due to the deformability of the elastic body, the bottle will be closed tightly even in cases where the opening of the bottle or ^" container to be closed is not perfectly round.

When the closing device is used with wine bottles or containers which should not be closed absolutely tightly but the closing device should allow "breathing", i.e., the entrance of very small amounts of air, the elastic body is made of a material containing microholes. In this embodiment, the pulling means, that is, the pull strip 2 or the coating 2 ' , also has to be made of a material com- prising microholes.

The invention has been described above with reference to its two preferred embodiments. It is to be understood that the .details of the closing device can be realized in various ways within the scope of the attached claims. As distinct from the embodiment

of Figures 7 to 11, the film 2a' can be omitted, whereby the closing device will be formed by the sub¬ stantially ball-shaped body and a coating attached to that side of the body which faces the contents of the bottle, whereby the coating covers said side of the body when the closing device is fitted in position. The elastic body can be made of cork to make it "breathe". The shape and structure of the pulling means made of a thin material may vary; essential is that it has certain basic properties so that the con¬ tainer (not necessarily a bottle) is easy to open, that is, the elastic body is easy to pull out of the opening of the container and preferably also easy to insert into the opening.