Teat Unit

Other features of the invention will be apparent from the following description of several embodiments shown by way of example only with reference to the accompanying illustrative drawings, in which:

FIG. 1 is an isometric view of a typical liquid container formed from a paper/plastics laminate;

FIG. 2 is a section through a typical paper/plastics laminate;

FIG. 3 is a side elevation of the invention in a simple form;

FIG. 4 is an axial section through a second embodiment of the invention;

FIG. 5 is a side elevation through a third embodiment of the invention somewhat similar to the embodiment of FIG. 4;

FIG. 6 is a partial axial section through a teat mounting and seal assembly;

FIG. 6a shows the assembly of FIG. 6 with a modified teat mounting;

FIG. 7 is a part axial section through the assembly of FIG. 6 inserted into a container and having a teat affixed thereto;

FIG. 8 is a side elevation of an alternative teat mounting;

FIG. 9 is an axial section through a teat mounting according to FIG. 8;

FIG. 10 corresponds to FIG. 9 and shows the mounting engaged in the wall of a liquid container;

FIG. 11 corresponds to FIGS. 9 and 10 and shows the mounting tightened in the container wall;

FIG. 12 shows a sterile teat, teat mounting and seal assembly packaged as an hermetically sealed unit; and

FIG. 13 is a side elevation of further alternative teat mounting.

With reference to FIG. 1 there is shown a liquid container 11 formed from a paper/plastics laminate. The container includes an entry port 12 of reduced thickness laminate through which a tube may be pushed to shear the remaining laminate layers; liquid may then be sucked through the tube.

Alternatively an end flap 13 may be lifted and torn or cut to provide a pouring spout for the container; dotted lines are often provided on the flap to indicate the best place to cut.

A section through a typical laminate 15 is shown in FIG. 2. A thin plastics layer 16, 17 is provided on either side of a relatively thick layer of carrier material 18. The plastics material may be polythene and the carrier material may be paper, card or some other fibrous material. The plastics material is of a type which can be easily heat sealed as the container is shaped. The laminate may include other layers, for example, a layer of aluminium foil, to provide an oxygen barrier and to reduce the transmission of light; the shelf life of the product is thereby prolonged.

Such liquid containers are light, flexible, have a good packing density and are resistent to transit damage. They are hermetically sealed to maintain the contents in a sterile condition and are suitable for ready to drink milks for babies. Containers of this type are sold, for example, under the names Tetrabrik (trade mark) and Combibloc (trade mark).

A simple embodiment of the invention is shown in FIG. 3. A teat unit 21 comprises a teat 22 attached by any convenient means to a tubular mounting 23. The mounting includes an extension spike for insertion through the port 12 so that liquid can pass to the teat. On insertion of the spike the polythene layer(s) will be partly sheared and partly stretched to grip the spike and prevent leakage when the container is held in the feeding position. Air is admitted to the container in the usual way be removing the teat from the babies mouth, alternatively any one of a number of known solutions can be provided to bleed air into the container to balance the volume of liquid withdrawn.

A sterile teat and mounting can be provided in an hermetically sealed package, as will be further described hereinafter so that prior to feeding both teat and liquid remain in a sterile condition.

After feeding has finished the container and teat unit can be thrown away.

An alternative teat unit is shown in FIG. 4. The mounting has a tapered threaded spike 25 (also shown in FIG. 5). The spike is pushed through the port 12 of the container and the wall of the port may stretch over several circuits of the thread 26 until the teat unit is almost fully inserted. The teat unit may then be turned to tighten the unit into the container until a flange 27 engages the container wall. The threaded spike ensures that the teat unit is positively engaged with the container; the abutment of the flange 27 with the outer surface of the container providing an additional seal against leakage of liquid.

The embodiment of FIG. 5 includes ears 28 for screwing the teat unit into the container, the ears assist in preventing contamination of the teat itself from the assemblers fingers.

The embodiments of FIGS. 4 and 5 are more suitable for older babies who can hold the container and feed themselves. The embodiment of FIG. 3 is suitable for small babies who are not able to pull the teat unit out of the container.

FIGS. 6 and 7 show an alternative push-in teat mounting 31 including a fluid seal 37. The mounting comprises a tubular body having spaced flanges 32, 33 at its outer end intended to locate a teat stretched over the outermost flange 32 (as shown in FIG. 7). A cylindrical spike 34 includes a regular tapered flange 35 increasing in diameter from the spike end to terminate in a shoulder 36 facing the flange 33. Between the shoulder 36 and flange 33 is an annular seal 37; the axial distance between shoulder and flange is somewhat less than the combined thickness of the seal 37 and the wall of the container 11.

In use the mounting, with or without teat attached, is pushed into the port 12, the port wall is stretched but not torn by the tapered flange 35 and the seal 37 compresses against the container wall to allow the port wall to snap into the gap between shoulder 36 and seal 37. The seal, which can be made of any suitable compressible resilient elastic material, expands to tightly seal the mounting against container as shown in FIG. 7.

In the alternative embodiment shown in FIG. 6a, the shoulder 36a is tapered toward the flange 33 to more tightly grip the container wall.

The mounting of FIGS. 6 and 7 provides a secure leak resistant teat attachment without screw-threading. This arrangement obviates the problem of the assembly not knowing which way to turn a screw-threaded mounting to tighten the unit against the container and not knowing the optimum tightening torque.

The embodiment shown in FIGS. 8 to 11 has a push and twist operation. The mounting 41 is shown with a double flanged outer end corresponding to FIG. 6 and for receiving a stretch-on teat. The spike 42 of the mounting includes a tapered flange 43 which terminates in a shoulder 44. The spike is threaded from the shoulder to the inner face of the flange 45; the thread is preferably a buttress thread as depicted and the shoulder 44 forms a lower buttress wall of the thread.

A co-axial annular extension 46 is provided on the flange 45 extending towards the tapered flange 43 and surrounding the upper portion of the thread. The extension 46 tapers from its inner to its outer diameter so that the height of the extension is greatest at the outer diameter.

In use the mounting 41 is pushed into the port 12 until the port wall snaps over the tapered flange 43 into the lower portion of the buttress thread; this position is shown in FIG. 10. The mounting is then turned until the container wall is squeezed firmly between the upper part of the thread and the annular extension 46 as shown in FIG. 11.

Such a construction provides a firm leak resistant connection between the mounting and the container without the use of separate sealing rings.

FIG. 12 shows a sterile teat and mounting unit enclosed in an hermetically sealed container 51. The teat is folded around the body of the mounting for packaging and is easily pulled into position on opening the container and removing the unit. The teat may be arranged to spring automatically into position by careful design of the mounting and teat. The container is shown enclosing a teat unit already described with reference to FIGS. 6 and 7 but any of the teat units described herein could be similarly packaged. The container may be sterilized by irradiation after packing.

FIG. 13 shows yet another alternative teat mounting comprising a hollow body 61 having a double flange 62, 63 to receive a stretch on teat and a sharply pointed threaded spike 64. The body has an opening extending from the upper flange into the spike; apertures 65 in the base of the thread communicate with the opening to provide a liquid supply path. This teat mounting is intended for use with liquid packs for which no port is provided. The user makes a hole with the sharply pointed end of the spike 64 and screws the spike into the container wall until the outer face of the container is in tight abutment with the underside of flange 63. Such a mounting is useful where it is intended to use an alternative type of liquid container or where a port provided on the container is not in a suitable place, for example the port may be too close to the container edge for an adequate seal to be maintained under all conditions of use. The mounting could of course be used in a container port if desired.

As an alternative the apertures 65 could be replaced by one or more axial slots between discontinuous portions of the screw thread. Other solutions are possible provided always that the spike has adequate mechanical strength to pierce a container wall.

The present invention has been described with reference to several example embodiments only; many modifications or alternatives are possible which would fall within the scope of the invention. For example, the teat could alternatively be attached to the mounting by adhesive or by crimping; the teat and mounting could be moulded as a single unit. The mounting is preferably of plastic but could be of any suitable material compatible with strength and hygiene requirements. The mounting may be for example, of polythene, polystyrene or cellulose acetate.

The thread shown on certain embodiments may be a regular conventional thread form or may vary in pitch or depth to suit the particular requirements of use. The thread profile may be rounded to ease insertion of the mounting, may be a buttress thread to provide positive engagement or may be a combination of both. Several thread forms may run together to provide a `quick-start` so that the minimum rotation of the unit will provide positive sealing engagement between the mounting and container. The profile and pitch of the thread form may vary along its length.

The invention has been described with particular reference to fluid containers made from a paper/plastic laminate. The containers would in the ordinary case hold quantities sufficient for a single feed for a baby but might be of the order of 100 ml to one litre in capacity.

The teat units disclosed herein are also suitable for use with other types of paper and plastic containers and might also be used with, for example, glass bottles sealed by a piercable membrane.

Although the applicants intend their invention for use with laminate containers of ready to feed milk formulations, the teat units can be used with any suitable packed liquid drink.