GB2199310A

GB2199310A - A teat with variable delivery for infant feeding

Info

Publication number: GB2199310A
Application number: GB08706270A
Authority: GB
Inventors: Gilles Blondeel; Claude Boiteau
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 1986-12-30
Filing date: 1987-03-17
Publication date: 1988-07-06
Anticipated expiration: 2007-03-17
Also published as: FR2608920A1; GB8706270D0; FR2608920B1; GB2199310B

Abstract

A teat intended to be fitted on a feeding bottle for infants has at least one dispensing slit (10). The slit is formed during moulding of the teat from rubber or elastomeric material, and has on the internal side of the teat longitudinal edges (12) forming between them an angle which is not zero. The rate of delivery from the teat depends upon the orientation of the slit with respect to the infant's mouth; to this end, the teat is provided with markers (I-III) to indicate orientation. <IMAGE>

Description

A TEAT WITH A VARIABLE AND ADJUSTABLE DELIVERY INTENDED TO BE FITTED ON A FEEDING BOTTLE FOR INFANT FEEDING The present invention relates to a teat with a variable and adjustable delivery, intended to be fitted on a feeding bottle for the feeding of infants.

In the first teats of this type, the opening for the infant's feed generally took the form of a rectiliner slit. These teats were made by hot moulding, then vulcanisation of a natural or synthetic rubber, in particular polyisoprene, in order to obtain teats without slits; the slits are subsequently made by a blade caused to descend onto the nipples of these teats.

However, such a manufacture presented a difficulty: in fact, because of the soft and elastic nature of the rubbers or elastomers constituting the teats, it proved impossible for the blade to ensure strict uniformity of the length of the slits. The difference obtained could be as much as approximately 0.5 mm and the flow delivered by the teats, largely depending on the length of the slit, was to a very great extent affected thereby.

Moreover, two drawbacks occurred during the use of these slitted teats. Firstly, the flow delivered by such a teat for a given position of the slit in relation to the median plane of the infant's head is not constant with respect to time: when the teat was used several times, the movements of the lips of the slit progressively tears off the ends of the slits under the effect of the infant's sucking, so that the slit length increases during use and the flow delivered to the infant with a given position of the teat is not the same depending on whether the teat is a new one or a used orie. Secondly, slitted teats generally impede the re-entry of air into the feeding bottle; when the infant's sucking action has caused a certain quantity of feed to be extracted from the bottle, the infant's action on the teat relaxes and the lips of the slit close against each other again so that in practice, air can no longer return into the feeding bottle through the slit, which causes low pressure inside the feeding bottle, renders the subsequent suction more difficult, and finally the teat is deformed to the point where one is compelled to let air return into the bottle through the base fixing the teat on the bottle.

To mitigate the above-mentioned drawbacks, it has been proposed in French Patent No. 2052206 that at least one of the ends, preferably both ends, of the slit of the teat should issue in a hole pierced through the wall of a teat.

In these conditions, each teat slit provided with a hole at each one of its ends retains a constant length during use of the teat, because the end of the slit is perfectly secured in the teat material by the existence of the hole itself.

Moreover, when the infant's sucking movement is no longer exerted on the teat, the lips of the slit close up again, but if there exists low pressure inside the teat, the air can return into the feeding bottle by passing through the end holes of each slit. These holes are made at the ends of the teat slits, either by means of piercing with heated needles, the material forming the teat being chosen from materials which are deformable by heat, e.g. polyisoprene, or by punching.

To ensure the adjustment of the delivery of a slit teat, whether or not incorporating end holes, by means of a larger or smaller opening of the slit, at each of the sucking movements of the infant's lips the position of the slit is modified in relation to the plane of symmetry of the infant's head. For this purpose, marks are made on the teat to allow the position of the slit to be adjusted during use by rotation of the feeding bottle around its axis. In the ordinary way, three marks are made, mark I being situated in that teat axial plane which is perpendicular to the slit, mark II being situated in that teat axial plane which forms an angle of 450 with the plane containing mark I, and Mark III being situated in that teat axial plane which contains the slit.When mark I is placed beneath the nose of the infant about to use the bottle, the suction movement is carried out without the occurrence of a large opening of the lips of the slit, that is to say, the minimum delivery is obtained from the teat; on the contrary, when mark III is disposed beneath the baby's nose by rotation of the feeding bottle around its axis, the maximum delivery is obtained because of the separation of the two lips of the slit; if the intermediate mark II is used, the feeding delivery falls between the deliveries obtained by use of the two marks I and III.

During experimental measurements of the delivery of these known teats - whose performance simulating the real conditions of use will be described in greater detail below - it has, however, been found that the delivery values found for the position corresponding to mark II are far from representing, as one would have wished, a mean value between the extreme values corresponding to marks I and III, nor even are those values close to this mean value which could have been deemed acceptable. In fact, for the position corresponding to mark 11, the delivery value obtained is only very slightly higher than that obtained with the position corresponding to mark I.

It follows from this that although an intermediate mark is made, an intermediate flow corresponding to it cannot be obtained even though this has proved to be necessary in practice.

The Applicants have discovered that when the slit of the teat is formed directly during moulding, and if the slit is given a particular shape (which would not have been possible with the prior art used for forming the slit with a cutter blade) in which the opposed longitudinal sides delimiting the slit diverge from each other in a direction towards the inside of the teat (instead of being parallel as in the case of known slit teats-) a delivery is obtained with the use of the intermediate mark II, which is really in between the two extreme values obtained during use of marks I and III respectively.

Apart from the fact that it was possible to achieve the objective aimed at in a totally unexpected manner, two additional advantages are obtained with the present invention: on the one hand, the teat manufacturing process is simplified by eliminating the stage of forming a slit by cutting and, if applicable, the stage wherein holes are made at the end of the slit; on the other hand, by the choice of a material which can be hot moulded to constitute the teat one can advantageously use a silicone rubber having a higher hardness than that of polyisoprene used hitherto.

The present invention therefore provides a teat with a variable and adjustable delivery intended to be fitted on an infants' feeding bottle, wherein said teat is made of a rubber or other elastomeric material and has, at the end of the nipple which is in use subjected to the infant's sucking movement, at least one slit on the internal side of the teat to pass the feed dispensed by the teat, and wherein said at least one slit has been formed during moulding of the teat and opens towards the inside of the said teat with opposed longitudinal sides which delimit the slit and slant to form between them an angle which is not zero.

Preferably the end of the teat comprises one single slit disposed in a radial plane of the teat. More preferably the or each slit cut in the teat end is rectilinear. Even more preferably the or each slit may have a longitudinal plane of symmetry.

In a particular embodiment of the invention, the or each slit opens out on the external side of the teat in an interstice delimited by two opposed longitudinal side zones which are substantially parallel to each other and are parallel to the axis of the teat; in that case the slanting zones of the longitudinal sides surrounding a slit advantageously extend over a height ranging from 50 to 95% of the thickness of the teat at the location where the slit is formed.

Each longitudinal slanting side, or side zone, surrounding a slit may form an angle of the order of 15 to 60 in relation to the plane passing through the longitudinal axis of the slit a-nd through the axis of the teat.

In three different embodiments the transverse sides delimiting the ends of a slit on the internal side of the teat are either (a) slanting flat sides forming between them an angle opening out towards the inside of the teat, or (b) flat sides disposed in planes perpendicular to the plane passing through the longitudinal axis of the slit and through the axis of the teat, or (c) curved sides shaped as half domes receding from each other towards the inside of the teat.

The or each slit of the teat may advantageously have a length of from 1 to 4 mm.

Moreover, the teat may conveniently be made of a material having a Shore A hardness situated in the range of from 25 to 40. For example the teat can be made of a silicone rubber having a Shore A hardness of the order of 35; this can advantageously replace the vulcanised polyisoprene used previously (Shore A hardness of approximately 27). However the choice of polyisoprene is consistent with the present invention.

When there are several slits, having a median line substantially parallel to one and the same plane P, the teat can in the conventional manner be provided with marks orientated in relation to the plane P, these marks being advantageously three in number. Such marks are for example constituted by reliefs formed near the base joining the teat to the feeding bottle.

In order that the present invention may more readily be understood there will now be described several embodiments represented in the accompanying drawings by way of purely illustrative and non-restrictive examples.

In these drawings: FIGURE 1 is a cross-sectional view of a teat in accordance with the invention, the plane of the cross-section being perpendicular to the plane which contains both the longitudinal axis of the slit and the axis of the teat; FIGURE 2 is a top plan view of the teat of Figure 1; FIGURES 3 and 4 are cross-sectional views along lines III-III and IV-IV, respectively, of Figure 2; FIGURES 5 and 6 are part views similar to Figure 4, showing two variants of the embodiment of the transverse sides delimiting a teat in accordance with the invention; and FIGURE 7 is a schematic view of the device used for measuring the delivery of a teat in the laboratory.

Referring now to Figure 1, it will be seen that 1 designates a teat in accordance with the invention. This teat is directly obtained by moulding a silicone- rubber having a Shore A hardness of 35, for example, that marketed under the Trade Mark "SILOPREN LSR 2035" by the "BAYER" Company.

The teat 1 is a conventional teat constituted by an ogive 2 surmounted by a nipple 3: the nipple 3 is subjected to the infant's sucking movements and comprises a substantially cylindrical portion 4 joined to the upper portion of the ogive 2 and an end portion 5 in the shape of a very flat dome.

At the opposite end to the nipple 3, the teat is turned towards the outside to form a base 6, which is intended to be applied to the upper edge of the neck of the feeding bottle by application of the upper side of this base 6 against the internal annular flange of a threaded ring for joining the feeding bottle to the teat by being screwed on the threaded neck of the feeding bottle.

The bottom side of the base 6 is provided with three equiangularly disposed groups of three radial ribs 7 obtained by moulding. The function of these ribs is, at one and the same time, to prevent the base 6 from sliding on the upper edge of the feeding bottle during use and to ensure an intake of air into the feeding bottle when the bottle is under low pressure. On the external wall of the body 2, just above the base 6, is a peripheral groove 8 intended to accommodate the lower edge of the flange of the above-mentioned connection ring.

In the end portion 5 is a rectilinear slit 10 located in a radial plane of the teat 1. As may be seen in greater detail in Figures 3 and 4, the slit 10 is delimited by two opposed longitudinal sides 11 and by two opposed transverse sides 12. The upper zones lla of the longitudinal sides 11 and the upper zones 12a of the transverse sides 1-2 are constituted by substantially rectangular elongate strips delimiting an interstice 10a through which the slit 10 opens to the outside of the teat 1. As for the lower zones llb and 12b of the -respective sides 11 and 12, they are slanted in opposed pairs and they recede from each other towards the inside of the teat 1.

The characteristic dimensions of the slit 10 in this example are as follows: 1 (length of the slit 10) : 1.5 and 2 mm; e (width of the interstice 10a of the slit 10) 0.1 mm; (inclination of the side zones llb in relation to the plane passing through the axis of the teat and through the longitudinal axis of the slit) : 250; oC2 (inclination of the side zones 12b in relation to the axis of the teat) : 400; h (height of the sides lla and 12a) : 0.1 mm.

In Figures 5 and 6, 112 and 212 designate respectively the transverse sides surrounding the slits 110 and 210 respectively, which are as a whole, similar to the slit 10 of the teat of Figures 1 to 4. In Figure 5 each side 112 is a flat side perpendicular to the longitudinal plane of symmetry of the slit 110 and the slit is completed by two opposed longitudinal flat sides which are slanted in relation to each other. The variant represented in Figure 6 is distinguished in that each transverse side 212 delimiting one end of the slit 210 has a half dome profile concave towards the inside of the teat; the opposed longitudinal sides 211 are flat and inclined in relation to each other, as in the previous variant.

Moreover, at the bottom edge of the ogive 2 of the teat 1 are three marks, I, II, III; the mark I is in the axial plane perpendicular to the slit 10 : mark II is in an axial plane of the teat 1 forming an angle of 450 with the plane containing mark I; mark III is in the axial plane of the teat 1 which contains the longitudinal axis of the slit 10. The respective marks, I. II, III are respectively constituted by one, two and three radial ribs moulded on the teat 1.

As is known, when the mark I is directly beneath the nose of the infant about to use the teat 1, the sucking movement is effected without any large opening of the two lips of the slit 10, that is to say that one obtains the minimum delivery from the teat 1. If, on the contrary, by rotating the feeding bottle around its axis, the mark III is disposed beneath the infant's nose the maximum delivery is obtained because of the separation of the two lips of the slit 10. If mark II is used, the delivery of the infant's feed lies in between the deliveries obtained in the two preceding cases.

It was possible to show by laboratory experiments that the delivery of the infant's feed obtained when the mark II is disposed beneath the infant's nose duly constitutes an intermediate delivery between the two respective minimum and maximum deliveries. These experiments will be described with reference to Figure 7.

Common characteristics of the teats used for these experiments are: - overall height of the teat : 39 mm - diameter of the teat in the upper plane of the groove 8 : 28 mm - external diameter of the end 3 of the teat in the most constricted portion of the end : 11.5 mm (this diameter is taken at 2 mm above the theoretical apex of the ogive 2) - external diameter of the teat 1 in the transition zone of portions 4 and 5 of the nipple 3 : 14 mm (this diameter is taken at a height of 15 mm above the theoretical apex of the ogive 2) - maximum height of the nipple 3 above the theoretical apex of the ogive 2 : 17 mm - thickness of the teat in its end portion 5 : 1 mm - thickness of the teat in the transition zone of portions 4 and 5 : 2 mm.

Record of the Measurements: Each of the teats under investigation, having the common characteristics as indicated above and differing by the dimensions or the shape of the outlet slit, is disposed with its tip lowermost and is subjected to an excess water pressure of 4000 Pa.

To measure the water delivery supplied by the teat two jaws 13a, 13b, capable of gripping the nipple, are applied on either side of the nipple 3 of the teat.

Each jaw 13a, 13b is constituted by a 14 mm thick plate, the respective faces 14a and 14b, intended to come into contact with the nipple 3, being constituted by cylindrical portions with their axes perpendicular to the jaws and having at the centre of their concavity a depth of 1.5 mm.

To measure the delivery of the teat according to the positions determined respectively by the marks, I, II, II, the nipple 3 is compressed whilst the teat subjected to the experiment is in one of three appropriate angular positions to simulate an actual situation with an infant in the region where its initial diameter is 14 mm by bringing the jaws 13a, 13b towards each other along the arrows F until the distance between the bearing points of the sides 14a and 14b on the nipple is 7 mm.

The above experiments have been carried out on one prior art teat and on two teats in accordance with Figure 5, the characteristics of the slits of these teats being set out in the Table below. In this Table, the deliveries obtained expressed in cm3/min are also set out. In the case of the teats in accordance with the invention, the sides 111 0 formed an angle of 25 with the axis of the teat and the width of the interstice where the slit 110 opens to the outside is 0.1 mm.

On examination of the results set out in the following Table, it will be found that in the case of the teats in accordance with the invention, the delivery corresponding to the use of the mark II approximates, as desired, to the mean value of the deliveries obtained with the teat placed in the positions corresponding to the marks I and III.

In this table there are four columns showing liquid flow rates. The first is the value obtained with no squeezing. In other words the water is expressed merely by the 4000 Pa water pressure behind the teat.

The next three columns are representative of the flow rate when the teat is squeezed in positions I, II and III respectively.

TABLE

Water flow rate (in cm3/mn) Material Characteristics Teat constituting of the Corresponding to use the teat slit Rate of in accordance with Outflow the marks I II III According to the Natural rubber Formed by a cutter blade prior art Shore A length : 2.8 mm 10 10 15 170 hardness = 27 two end holes 0.1 mm in diameter Formed during moulding According to the Silicone Rubber and such as represented 15 - 20 100 224 320 invention Shore A in Figure 5 hardness = 35 length: 1.5 mm According to the Silicone Rubber Formed during moulding invention Shore A and such as represented 45 110 240 352 hardness = 35 in Figure 5 length : 2.0 mm

Claims

1. A teat with a variable and adjustable delivery intended to be fitted on an infants ' feeding bottle, wherein said teat is made of a rubber or other elastomeric material and has, at the end of the nipple which is in use subjected to the infant's sucking movement, at least one slit on the internal side of the teat to pass the feed dispensed by the teat, and wherein said at least one slit has been formed during moulding of the teat and opens towards the inside of the said teat with opposed longitudinal sides which delimit the slit and slant to form between them an angle which is not zero.

2. A teat according to claim 1, wherein said end of the nipple comprises a single slit disposed in a radial plane of the teat.

3. A teat according to either of claims 1 and 2, wherein the or each slit in the end of the teat is rectilinear.

4. A teat according to any one of claims 1 to 3, wherein the or each slit has a longitudinal plane of symmetry.

5. A teat according to any one of claims 1 to 4, wherein the or each slit opens out on the external side of the teat by means of an interstice delimited by two opposed longitudinal side zones which are substantially parallel to each other and parallel to the axis of the teat.

6. A teat according to claim 5, wherein the slanting zones of the longitudinal sides surrounding a slit extend over a height ranging from 50 to 95% of the thickness of the teat at the location where the slit is formed.

7. A teat according to any one of claims 1 to 6, wherein each slanting longitudinal side or side zone surrounding a slit forms an angle of the order of 150 to 600 in relation to the plane which passes through both the longitudinal axis of the slit and the axis of the teat.

8. A teat according to any one of claims 1 to 7, wherein the transverse sides delimiting the ends of one slit on the internal side of the teat are flat slanting sides diverging from one another in a direction towards the inside of the teat.

9. A teat according to any one of claims 1 to 7, wherein the transverse sides delimiting one slit on the internal side of the teat are flat sides disposed in planes perpendicular to the plane which passes through both the longitudinal axis of the slit and the axis of the teat.

10. A teat according to any one of claims 1 to 7, wherein the transverse sides delimiting a slit on the internal side of the teat are curved sides shaped as a half dome concave towards the inside of the teat.

11. A teat according to any one of claims 1 to 10, wherein the or each slit has a length of from 1 to 4 mm.

12. A teat according to any one of claims 1 to 11, wherein it is made of a material having a Shore A hardness situated in the range from 25 to 40.

13. A teat according to claim 12, when made of a silicone rubber having a Shore A hardness of the order of 35.

14. A teat according to any one of claims 1 to 13, comprising: several said slits each having a median line substantially parallel to a common plane; and marks orientated in relation to the common plane.

15. A teat according to any one of claims 1 to 13, and comprising: a single said slit; and marks orientated in relation to the median line of said slit.

16. A teat according to claim 14 or 15, wherein said marks od the teat are reliefs formed near the base for joining the teat to the feeding bottle.

17. A teat according to any one of claims 14 to 16, wherein there are three of said marks.

18. A teat substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 to 4, or Figure 5, or Figure 6, of the accompanying drawings.