This invention relates to a nipple. More particularly it concerns a nipple for liquid feeding wherein the suction portion of the nipple comprises a flexible, outer membrane, and wherein the suction portion of the nipple is provided _/ with an opening therethrough and wherein the outer membrane abuts an inner body in a common contact face, as the opening communicates with the contact face .

Nipples adapted to fit feeding bottles for children have a tendency to leak when the nipple is designed in a traditional way. This may cause an unwanted mess, but may also present a danger if the liquid leaks out in the mouth of an infant without the infant sucking.

It is known to provide a nipple with a valve arrangement to counteract unwanted leakage. GB 2246300 thus describes an arrangement where an opening for through flow is made when the nipple is pulled in the direction outward from the feeding bottle.

According to US 2584359 the nipple internally abuts a body which, when the nipple is positioned in its initial position, covers in a closing manner or plugs a suction opening in the nipple . Common for all prior art valve arrangements is that they may ^¬ be brought to leak by mechanical influence from the outside, such as squeezing the nipple.

The object of the invention is to remedy or reduce at least one of the prior art drawbacks .

The object is achieved according to the invention by the features stated in the description below and in the following claims.

There is provided a nipple for liquid feeding wherein the nipple comprises a flexible outer membrane and wherein the suction portion of the nipple is provided with an opening therethrough and wherein the outer membrane abuts an inner body in a common contact face, as the opening communicates with the contact face, and wherein the nipple is characterised in that the inner body is constituted by a flexible inner membrane.

It is thereby avoided that the nipple leaks even if the suction portion is squeezed together as the flexible inner membrane adapts itself to the outer membrane. It is further not necessary to fasten the inner membrane to the remainder of the nipple portions.

The outer membrane is in use arranged to be able to be pulled out from the inner membrane by means of an external underpressure. The contact face of the outer membrane is thereby displaced out from the contact face of the inner membrane. Liquid may thus flow in between the contact faces and out via the opening.

The inner membrane may be formed as a part of the nipple material. Even if the nipple and the inner membrane are formed as one piece, they may if desired be constituted of different materials.

The inner membrane may be reversibly connected to the nipple. By turning the nipple inside out at least a portion of the contact face may be exposed.

This facilitates to a considerable degree the cleaning of the nipple being otherwise difficult when the nipple is provided with a valve arrangement .

The common contact face may have any shape, and it may for example be spherically shaped.

The inner membrane may seal against the outer membrane in a radial direction relative to the longitudinal axis of the nipple. This makes it possible to form the common contact face having some preloading along an annular portion of the inner membrane further contributing to an efficient seal against leakage.

A slit, a through slot or some other appropriate opening may constitute the opening.

The outer membrane may be constituted by such as an annular portion positioned between the inner membrane and the outer wall of the suction portion. In case of an external underpressure the inner membrane will then be pulled away from the annular portion.

The device according to the invention provides a simple nipple which, when no underpressure is established around the suction portion, seals even if treated relatively roughly. The nipple opens for through flow when an underpressure, such as a suction from a user, is established on the outside of the suction portion. In the following is described an example of a preferred embodiment illustrated on the accompanying drawings, wherein:

Fig. 1 shows in perspective and sectioned a nipple according to the invention;

Fig. 2 shows in section and in a larger scale a section of the nipple of fig. 1;

Fig. 3 shows the same as fig. 2 but with the nipple turned inside out;

Fig. 4 shows in section a nipple according to the invention in an alternative embodiment;

Fig. 5 shows a section of the nipple of fig. 4 wherein the inner membrane has been turned inside out from the outer membrane;

Fig. 6 shows a section of the nipple of fig. 4 wherein the nipple has been turned inside out; and

Fig. 7 shows in section and in a larger scale the suction portion of fig. 4, as the suction portion experiences an external underpressure.

In the drawings the reference numeral 1 indicates a nipple comprising a suction portion 2 and a fastening portion 4 adapted to a not shown container.

The suction portion 2 comprises an outer flexible membrane 6 provided with a through opening 8.

On the inside of the outer membrane 6 there is arranged an inner body in the form of a flexible inner membrane 10 abutting sealingly against the outer membrane 6 along a common contact face 12 on the inside of the outer membrane 6 and a second opposing contact face 14 on the inner membrane 10. Inner and outer refers here to the condition of the nipple when it is ready for use as shown in figs. 1 and 2.

In this preferred embodiment the inner membrane 10 constitutes a part of the material of the nipple 1, as the inner membrane 10 is made integrated in the nipple 1. In the embodiment in figs. 1 and 2 the nipple 1 will also function even if the inner membrane 10 is a separate component.

When a not shown user applies a suction to the outside of the suction portion 2, the outer membrane 6 is displaced out from the inner membrane 10, whereby liquid may flow in between the first contact face 12 and the second contact face 14, and further out through the opening 8. When the suction is eased, the outer membrane 6 is closed against the inner membrane 10.

In fig. 3 is shown a section of the nipple 1 in a condition turned inside out whereby the contact faces 12 and 14 are exposed for cleaning. By turning the nipple 1 inside out again, the inner membrane 10 returns to its position for use as shown in figs. 1 and 2.

In an alternative embodiment, see fig. 4, the inner membrane 10 is constituted by an in the suction portion inwards facing, cylindrical sleeve. The inner membrane 10 is connected to the outer membrane 6 along its end circumference 16. The opening 8 in fig. 4 is positioned at the end circumference 16, but may if desirable be positioned at a distance from this, also in the inner membrane 10.

At suction about the suction portion 2 both membranes 6, 10 are displaced away from each other, see fig. 7.

In fig. 5 is shown the suction portion 2 of fig. 4 where the inner membrane 10 is turned inside out from the outer membrane 6 for thereby being able to be cleaned inside. In fig. 6 the nipple 1 is turned inside out, whereby the contact faces 12, 14 are exposed.

In both embodiments the inner membrane 14 seals against the outer membrane 6 also in a radial direction relative to the longitudinal axis 18 of the nipple 1.