SELF-CLOSING DISPENSING VALVE MADE OF A PLASTOMER OR A THERMOPLASTIC ELASTOMER

Abstract

A self-closing dispensing valve is made of an elastic material and includes a valve head with a dispensing orifice, a circular peripheral retaining flange spaced apart from the valve head in an axial direction, and a connector sleeve integrally connected with the valve head on one end and the retaining flange on another end. The elastic material is a plastomer or a thermoplastic elastomer. The connector sleeve is substantially form stable. The valve head is connected to an upper end of the connector sleeve by a hinge portion that is U-shaped in cross section. The wall thickness of the hinge portion is smaller than the wall thickness of the connector sleeve and is staggered at the transition between the connector sleeve and the hinge portion. Alternatively, if the connector sleeve is omitted, then the valve head is directly connected to the retaining flange.

Claims

1. A self-closing dispensing valve made of an elastic material, said valve comprising a valve head with a dispensing orifice, a circular peripheral retaining flange spaced apart from the valve head in an axial direction, and a connector sleeve integrally connected with the valve head on one end and the retaining flange on another end, wherein: the elastic material is a plastomer, the valve head has a dome shape with a concave exterior side and a convex interior side, the connector sleeve is substantially form stable and has a wall thickness, the valve head is connected to an upper end of the connector sleeve by a hinge portion that is U-shaped in cross section, wherein the hinge portion has a wall thickness which is smaller than the wall thickness of the connector sleeve, and wherein at a transition between the connector sleeve and the hinge portion the wall thickness of the hinge portion is staggered.

2. The self-closing valve according to claim 1, wherein the wall thickness of the hinge portion is smaller than the wall thickness of the valve head.

3. The self-closing valve according to claim 1, wherein the hinge has a uniform wall thickness.

4. The self-closing valve according to claim 3, wherein the wall thickness of the hinge portion is 0.2 mm.

5. The self-closing valve according to any claim 1, wherein the U-shaped hinge portion has a convex side which has a radius of curvature of about 0.43 mm.

6. The self-closing valve according to claim 1, wherein the connector sleeve has a uniform wall thickness.

7. The self-closing valve according to claim 1, wherein the wall thickness of the connector sleeve is at least twice the wall thickness of the hinge portion.

8. (canceled)

9. The self-closing valve according to claim 1, wherein the valve head has a uniform wall thickness.

10. The self-closing valve according to claim 9, wherein the wall thickness of the valve head is about 0.25 mm.

11. The self-closing valve according to claim 1, wherein the valve head has a diameter Dvh, and wherein the concave exterior side of the valve head has a radius of curvature R1, wherein 0.90≤Dvh/R1≤1.15.

12. The self-closing valve according to claim 1, wherein the concave exterior side has a radius of curvature R1 of 9.5 mm.

13. The self-closing valve according to claim 1, wherein the convex interior side of the valve head has a radius of curvature of 9.75 mm.

14. 20. (canceled)

21. The self-closing valve according to claim 1, wherein the connector sleeve is substantially cylindrical.

22. The self-closing valve according to claim 1, wherein the connector sleeve is at least partly tapering from the retaining flange towards the valve head.

23. The self-closing closing valve according to claim 1, wherein the dispensing orifice is defined by at least one through slit in the valve head.

24.-36. (canceled)

37. A self-closing dispensing valve made of an elastic material, said valve comprising a valve head with a dispensing orifice, a circular peripheral retaining flange spaced apart from the valve head in an axial direction, and a connector sleeve integrally connected with the valve head on one end and the retaining flange on another end, wherein the elastic material is a thermoplastic elastomer, wherein the valve head has a dome shape with a concave exterior side and a convex interior side, wherein the connector sleeve is substantially form stable and has a wall thickness, First Named Inventor: Marcel Pater Application No.: Unassigned Filing Date: Herewith Docket No.: 903-768 PCT/US Page 10 wherein the valve head is connected to an upper end of the connector sleeve by a hinge portion that is U-shaped in cross section, wherein the hinge portion has a wall thickness which is smaller than the wall thickness of the connector sleeve, and wherein at a transition between the connector sleeve and the hinge portion the wall thickness of the hinge portion is staggered.

38. The self-closing valve according to claim 37, wherein the wall thickness of the hinge portion is smaller than the wall thickness of the valve head.

39. The self-closing valve according to claim 37, wherein the hinge has a uniform wall thickness.

40. The self-closing valve according to claim 37, wherein the connector sleeve has a uniform wall thickness.

41. The self-closing valve according to claim 37, wherein the wall thickness of the connector sleeve is at least twice the wall thickness of the hinge portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] FIG. 1 shows a view in perspective of an embodiment of a self-closing valve according to the invention made of a plastomer material,

[0065] FIG. 2 shows a top elevational view of the valve of FIG. 1,

[0066] FIG. 3 shows a cross section of the valve according to the line A-A indicated in FIG. 2,

[0067] FIG. 4 shows a view in perspective of an embodiment of a self-closing valve according to the invention made of a thermoplastic elastomer (TPE) material,

[0068] FIG. 5 shows a top elevational view of the valve of FIG. 4,

[0069] FIG. 6 shows a cross section of the valve according to the line A-A indicated in FIG. 5,

[0070] FIGS. 7a-7e show in a view in perspective a 1/8.sup.th section of the valve of FIG. 1 in different states,

[0071] FIGS. 8a-8e show in another view in perspective a 1/8.sup.th section of the valve of FIG. 1 in the same states as in FIG. 7a-7e,

[0072] FIG. 9 shows a top elevational view of the valve of FIG. 1 in the states corresponding to FIGS. 7a-7d,

[0073] FIG. 10 shows a view in perspective of a dispensing closure including the valve of FIG. 1,

[0074] FIG. 11 shows a detail of the closure of FIG. 10 in cross section,

[0075] FIG. 12 illustrates the change of the width of a hinge portion of the valve of FIG. 1,

[0076] FIG. 13 shows an opening radius vs. pressure curve of two valves of type of the valve of FIG. 1 and a reference valve made of silicone rubber,

[0077] FIG. 14 shows a cross sectional view of another possible self-closing valve according to the invention, and

[0078] FIG. 15 shows in detail a cross section of a hinge portion of the valve of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

[0079] FIGS. 1-3 show an embodiment of a self-closing valve 1 according to the invention. The valve 1 is made by injection moulding or injection compression moulding of an elastic material, in particular a plastomer.

[0080] The valve 1 comprises a valve head 2 with a dispensing orifice. The dispensing orifice is formed by two intersecting through slits 3. The through slits 3 intersect in the centre of the valve head 2. The valve furthermore comprises a circular peripheral retaining flange 4 spaced apart from the valve head 2 in an axial direction. In the embodiment shown the flange comprises a thickened outer portion. A connector sleeve 5 is integrally connected with the valve head 2 on one end and the retaining flange 4 on another end.

[0081] To get an idea of the overall dimensions, a practical embodiment of the valve 1 has an outer diameter D.sub.o of about 16.4 mm, and a height H of 5.4 mm. The valve head 2 has a diameter D.sub.vh of about 9.7 mm.

[0082] The valve head 2 of the valve 1 has a dome shape with a concave exterior side 6 and a convex interior side 7 as can be best seen in FIG. 3.

[0083] The valve head 2 is connected to an upper end 5A of the connector sleeve 5 by a hinge portion 8 that is U-shaped in cross section, as can be best seen in FIG. 3 and in detail in FIG. 15. The wall thickness th of the hinge portion 8 is smaller than the wall thickness t.sub.cs of the connector sleeve 5 and is staggered at the transition. The staggered transition is indicated by reference number 9 between the connector sleeve 5 and the hinge portion 8.

[0084] The connector sleeve 5 in this embodiment is slightly tapering from the retaining flange 4 towards the valve head 2, thus almost cylindrical. The small inclination of the connector sleeve 5 with respect to the centre axis of the valve 1 facilitates ejection of the valve 1 out of the mould. However, the connector sleeve may also have another shape for example partly cylindrical and partly tapering from the retaining flange towards the valve head.

[0085] The wall thickness of the hinge portion th is smaller than the wall thickness t.sub.vh of the valve head 2.

[0086] The hinge portion 8 has a uniform wall thickness t.sub.h, which in a preferred practical embodiment is 0.2 mm.

[0087] The hinge portion has a convex side which has a radius of curvature R.sub.h (cf. FIG. 15) of about 0.43 mm.

[0088] The connector sleeve 5 has a uniform wall thickness t.sub.cs. The wall thickness t.sub.cs of the connector sleeve 5 is at least twice the wall thickness t.sub.h of the hinge portion 8. The wall thickness t.sub.cs of the connector sleeve 5 is in a practical embodiment 0.4 mm. The connector sleeve 5 having this wall thickness and made of plastomer material is form stable.

[0089] The valve head 2 of the valve 1 has a uniform wall thickness, which is preferably about 0.25 mm.

[0090] The valve head 2 has a diameter D.sub.vh, and the concave exterior side 6 of the valve head 2 has a radius of curvature R1, wherein 1.00≤D.sub.vh/R1≤1.15.

[0091] In the practical embodiment shown the concave exterior side has a radius of curvature R1 of 9.5 mm and the convex interior side 7 of the valve head 2 has a radius of curvature R2 of 9.75 mm.

[0092] FIGS. 10 and 11 illustrate how the valve 1 is arranged in a closure 20 for a squeeze container, e.g. a bottle containing an edible sauce like ketchup, mayonnaise etc. The closure 20 shown in FIG. 10 is a so called flip top closure comprising a closure body 21 and a lid 22, which is integrally connected to the closure body 21 by a living hinge 23. The closure body 21 comprises a deck 24 in which a dispensing passage 25 is formed. Furthermore the closure body comprises a skirt 26 depending from the deck 24 and defining an interior space of the closure 20. A valve seating portion 27 is formed in the interior space in line with the dispensing passage 25 as is shown in the cross section of FIG. 11. In this particular embodiment the valve seating portion includes foldable lips 28 which are folded over the retaining flange 4 of the valve 1 after the valve is placed in the valve seating portion 27, so as to retain the valve 1 in the closure body 21. This can for example be done by ultrasonic welding which provides the energy to plastically deform the foldable lips 28.

[0093] In FIGS. 7a-7e and 8a-8e is illustrated how the valve 1 works by showing the deformation of a 1/8 section of the valve 1. The slit 3 is on the far side. FIGS. 7a and 8a show the rest state of the valve 1. When a pressure is applied on the valve 1 from the interior side, typically because the container on which the closure 20 is mounted is squeezed, the hinge portion 8 of the valve unbends to some extent as is visible by the comparison of the FIGS. 7a and 8a with FIGS. 7b and 8b, respectively. As can be seen in FIGS. 7b and 8b the valve head 2 is moved in axial direction in a direction away from the retaining flange 4, in the FIGS. 7b and 8b upwards. As can be seen the tip 10 of the valve head flaps defined by the slits 3 is still situated along the centre axis CA of the valve 1 and thus the valve is still closed. Upon further increase of the pressure on the interior will pass a threshold pressure and the valve flaps will start to bend and the slits 3 are opened. In the FIGS. 7c and 8c this is illustrated. Also in FIGS. 9b and 9c this is shown from above. In the embodiment of the valve as described and shown in the FIGS. 1-3, this opening of the valve orifice is instantaneous a relatively large opening as is shown in FIG. 9c. Upon further increase of the pressure the valve will more gradually open further to the state that is illustrated in FIGS. 7d, 8d and 9d.

[0094] In FIG. 13 a plot is shown which also illustrates the behaviour of the valve 1 compared with a similar self-closing valve made of a silicone rubber. On the vertical axis the pressure is indicated in mm H.sub.2O, on the horizontal axis the opening radius of the valve orifice is indicted in mm. The plot with the dots is indicated with reference numeral 11 and is representing the behaviour of the silicone valve, which serves as a reference for the valves 1 made of a plastomer. The plot with the X indicated with reference numeral 12 is representing a first embodiment of the valve 1. The plot with the X indicated with reference numeral 13 is representing a second embodiment of the valve 1, wherein the U-shape of the valve 1 is wider than for the first embodiment. This difference is illustrated in FIG. 12, wherein the first embodiment (plot 12) is the lower valve and the second embodiment (plot 13) is the upper valve in FIG. 12. The width U (cf. FIG. 12) is thus larger in the second embodiment than in the first embodiment.

[0095] As is derivable from the plot, the pressure can be increased up to 325 and 375 mm H.sub.2O, respectively before the valve 1 starts to open. The relatively horizontal development of the graph shows that the dispensing orifice 15 (cf. FIGS. 9b-9d) opens quickly to an opening radius of about 2 mm. Upon further increase of the pressure the increase of the valve radius follows a more gradual curve, in practice up to about 2.5 mm.

[0096] As can be seen the narrower U-shape opens at a lower pressure (i.e. 325 mm H.sub.2O) than the reference valve made of silicone rubber. By increasing the width U of the U-shaped hinge portion 8 the plot can be raised to the pressure level (i.e. 375 mm H.sub.2O) at which the reference valve opens.

[0097] As mentioned the valve 1 is typically used with a squeeze bottle, which after squeezing and dispensing of substance automatically wants to return to its original shape. The valve 1 is initially closed after dispensing of substance. This creates an underpressure on the interior side of the valve head 2. The valve 1 allows venting air to enter in the container, such that the container can return to its original shape. Thereto the U-shaped hinge portion 8 of the valve 1 bends further inwards such that the valve head 2 moves axially towards the interior, thus sinks further into the connector sleeve and eventually the valve head sections bend whereby the dispensing orifice is opened and venting air is allowed to pass through the valve into the container. This state is illustrated in FIGS. 7e and 8e. From the plots 12, 13 in FIG. 13 one can see that the valve 1 opens following a linear curve to a maximum radius of the orifice of about 1 mm at a negative pressure of 475 mm H.sub.2O.

[0098] In FIGS. 4-6 another embodiment of a self-closing valve according to the invention is shown This valve indicated by 101 is made by injection moulding or injection compression moulding of a thermoplastic elastomer TPE.

[0099] The valve 101 comprises a valve head 102 with a dispensing orifice. The dispensing orifice is formed by two intersecting through slits 103. The through slits 103 intersect in the centre of the valve head 102. The valve 101 furthermore comprises a circular peripheral retaining flange 104 spaced apart from the valve head 102 in an axial direction. In the embodiment shown in FIGS. 4-6 the flange 104 comprises a thickened outer portion 104A. A connector sleeve 105 is integrally connected with the valve head 102 on one end and the retaining flange 104 on another end.

[0100] To get an idea of the overall dimensions, a practical embodiment of the valve 101 has an outer diameter D.sub.o of about 16.4 mm, and a height H of 5.4 mm. The valve head 102 has a diameter D.sub.vh of about 9.7 mm. This is thus the same as the valve 1 of FIG. 1 which is made of a plastomer.

[0101] The valve head 102 of the valve 101 has a dome shape with a concave exterior side 106 and a convex interior side 107 as can be best seen in FIG. 6.

[0102] The valve head 102 is connected to an upper end 105A of the connector sleeve 105 by a hinge portion 108 that is U-shaped in cross section, as can be best seen in FIG. 6 and in detail in FIG. 15. The wall thickness th of the hinge portion 108 is smaller than the wall thickness t.sub.cs of the connector sleeve 105 and is staggered at the transition. The staggered transition is indicated by reference number 109 between the connector sleeve 105 and the hinge portion 108. This part of the valve 101 is also the same as of the valve 1. In a practical embodiment it may thus have the same dimensions:

[0103] The wall thickness of the hinge portion th is smaller than the wall thickness t.sub.vh of the valve head 102.

[0104] The hinge portion 108 has a uniform wall thickness t.sub.h, which in a preferred practical embodiment is 0.2 mm.

[0105] The hinge portion has a convex side which has a radius of curvature R.sub.h (cf. FIG. 15) of about 0.43 mm.

[0106] The connector sleeve 105 has a uniform wall thickness t.sub.cs. The wall thickness t.sub.cs of the connector sleeve 105 is at least twice the wall thickness t.sub.h of the hinge portion 108. The wall thickness t.sub.cs of the connector sleeve 105 is in a practical embodiment 0.4 mm. The connector sleeve 105 having this wall thickness and made of a thermoplastic elastomer (TPE) material is form stable.

[0107] The connector sleeve 105 in this embodiment is slightly tapering from the retaining flange 104 to the valve head 102, thus almost cylindrical. The small inclination of the connector sleeve 5 with respect to the centre axis of the valve 1 facilitates ejection of the valve 1 out of the mould.

[0108] The valve 101 made of TPE is formed differently from the valve 1 made of plastomer when it comes to the shape of the valve head.

[0109] Unlike the valve 1 the valve 101 does not have a valve head with a constant wall thickness, but the valve head 102 has a wall thickness t.sub.vh that tapers towards the centre of the valve head. In other words the valve head is thinnest at the centre and its wall thickness increases when going radially outwardly.

[0110] In a practically good working embodiment the wall thickness t.sub.vh1 of the valve head 102 at the centre is 2/3 of the wall thickness t.sub.vh2 at the circumference of the valve head 102. In a practical embodiment the wall thickness t.sub.vh1 at the centre of the valve head 102 is about 0.4 mm.

[0111] The valve head 102 has a diameter D1, and wherein the concave exterior side 106 of the valve head 106 has a radius of curvature R1, wherein 1,2≤D.sub.vh/R1≤1.6, preferably about 1.5.

[0112] In a practical embodiment the concave exterior side 106 has a radius of curvature R1 of 6.5 mm and the convex interior side 107 of the valve head 101 has a radius of curvature of 7.75 mm. The valve head 102 of the valve 101 has thus a more convex and more concave shape than the valve head 2 of the valve 1; in other words the valve head 2 is “flatter” than the valve head 102.

[0113] In FIG. 14 a self-closing dispensing valve 201 according to a further aspect of the invention is shown. This dispensing valve 201 is made of an elastic material, in particular of a TPE. The valve 201 comprises a valve head 202 with a dispensing orifice, and a circular peripheral retaining flange 204 integrally connected with the valve head 202. A difference with the valves 1 and 101 described in the above is thus that a connector sleeve is omitted.

[0114] The valve head 201 has a dome shape with a concave exterior side 206 and a convex interior side 207. The peripheral retaining flange 204 is substantially form stable. The valve head 202 is connected directly to the retaining flange 204 by a hinge portion 208 that is U-shaped in cross section.

[0115] In this embodiment the retaining flange is a thickened ring which is substantially form stable. However, it is also conceivable to make a more flexible retaining flange which is attached, for example welded to a more rigid plastic ring.

[0116] To get an idea of the overall dimensions, a practical embodiment of the valve 201 has an outer diameter D.sub.o of about 10.3 mm, and a height H of 2.0 mm. The valve head 202 has a diameter D.sub.vh of about 6.2 mm.

[0117] In the valve 201 the wall thickness th of the hinge portion 208 is smaller than the wall thickness t.sub.vh of the valve head 202.

[0118] The hinge portion 208 has a uniform wall thickness, which in a practical embodiment as is shown here is 0.2 mm.

[0119] The U-shaped hinge portion 208 has a convex side which has a radius of curvature of about 0.43 mm.

[0120] The valve head has a uniform wall thickness, which in a practical embodiment is about 0.25 mm.

[0121] The concave exterior side of the valve head 202 has a radius of curvature R1. The form of the valve head made of a plastomer is such that 1.2≤D.sub.vh/R1≤1.6, preferably around 1.5.

[0122] It is noted that the valve 201 described in the above has relatively small dimensions (outer diameter D.sub.o=10.3 mm etc). In such a small valve the use of a plastomer is very difficult due to the relatively high stiffness of food-approved plastomers. The wall thicknesses would become too small to process when using a suitable plastomer for the small valve 201, in order to achieve a valve with a sufficiently large dispensing opening. Therefore the smaller valve 201 is made in a suitable TPE grade. However, if the valve 201 is made larger, thus with a larger outer diameter etc., the use of a suitable plastomer is conceivable.

[0123] The dispensing orifice of the valve 201 is formed by one or more through slits. For a small valve (e.g. Do=10.3 mm), which is described in the foregoing, two, preferably perpendicular, through slits form a T-configuration such that a sufficiently large dispensing opening can be obtained in the small valve. For valves 201 with a larger dimension a dispensing orifice defined by through slits in a more common cross-configuration (see FIG. 2 for an example) may be provided.