WO2009127801A1

WO2009127801A1 - Valves for packaging containers

Info

Publication number: WO2009127801A1
Application number: PCT/GB2009/000471
Authority: WO
Inventors: Martin Carey Bull
Original assignee: Obrist Closures Switzerland Gmbh
Priority date: 2008-04-18
Filing date: 2009-02-20
Publication date: 2009-10-22
Also published as: GB0807119D0

Abstract

A self-closing valve (10) for a packaging container is provided. The valve comprises a marginal region (20) by which the valve can be peripherally secured in the discharge opening of the container, a valve head (30) having an openable dispensing aperture (50, 55, 60) and being movable between a fully closed position in which it forms a seal and a fully open position in which a maximum usable aperture size is available for product dispensing, and a connecting wall (40) arranged between the marginal region and the valve head, wherein the valve head is movable to one or more stable intermediate positions defining one or more intermediate aperture sizes for product dispensing.

Description

VALVES FOR PACKAGING CONTAINERS

The present invention relates generally to a valve and particularly to a self-closing valve for a packaging container.

It is known to provide self-closing valves for packaging containers. That is to say, valves which open in response to an elevated pressure of the product in a packaging container and which close again automatically and in a self-sealing manner when the pressure has subsequently been reduced to below ambient pressure.

Self-closing valves¹ are well known and examples of them are disclosed in published patent specifications EP0545678, EP0395380, US6273305 and US5439143 amongst many others.

Self-closing valves have been proposed for use with a wide variety of liquid foods and other products including ketchups, washing-up liquids and shower gels.

Self-closing valves are provided with an aperture through which product is dispensed. The most common form of aperture is defined by one or more slits. Whatever form the aperture takes, the maximum aperture size defined is fixed and constant. It is usual to select an aperture size based upon the product which will be dispensed. However, some products are not homogenous and this can cause problems for known self- closing valves. For example,^' products such as relishes and pickles include both liquid and solid particulate material. Valves for such products must be designed so that the maximum aperture size is sufficient to allow the passage of the largest particles and this can create problems with the dispensing of smaller particles and liquid phase material.

The present invention seeks to address the problems with.self-closing valve.

According to. a first aspect of the present invention there provided a self-closing valve for a packaging container, the valve comprising a marginal region by which the valve can. be peripherally secured in the discharge opening of the container, a valve head having an openable dispensing aperture and being movable between a fully closed position in which it forms a seal and a fully open position in which a maximum usable aperture size is available for product dispensing, and a connecting wall arranged between the marginal region and the^' valve head, wherein the valve head is movable to one or more stable intermediate positions defining one or more intermediate aperture sizes for product dispensing. Because the valve head has one or more intermediate positions this allows one or more different aperture sizes to be defined in addition to the fully open size. In turn this allows the valve to function with two or more different aperture sizes which can be preselected to match the constituents of a product.

Movement of the valve head between the positions is determined by the internal pressure of the container. For example, the valve head could be configured to move from the closed to an intermediate position once a first threshold pressure is reached. A second, larger, threshold is required to cause the valve head to move from the intermediate to the open position.

The aperture may extend into the connecting wall. By extending the aperture into the wall it is possible to restrict the aperture size in intermediate positions by controlling the configuration of the wall as it moves with the valve head in response to changes in internal pressure.

The connecting wall may include one or more fulcrum points defining the or each intermediate position. The position of the fulcrum point/s is important in defining the working mechanism.

At least part of the connecting wall may have a resiliently flexible construction such that when pressure within the container raised above a predetermined amount the valve head shifts outwardly and causes the wall to double over and extend rollingly.

The connecting wall may comprise first and second portions joined together at a V- form elbow, the wall being of increased wall thickness at the elbow whereby during operation of the valve the elbow may keep its identity and act as resiliently as a spring for returning the valve head to its fully closed position.

The aperture may comprise one or more slits. The orifice may comprise at least two slits oriented in a mutually intersecting relationship which result in 'petals' that flex inwardly and outwardly to selectively permit the flow of product. The length and location of slits can be used in part to determine opening and closing pressures.

The valve may be formed from any suitable material for example silicon or a thermoplastic elastomer (TPE). According to α second aspect there is provided a self-closing valve for a packaging container, the valve comprising a valve head having an openable dispensing aperture, in which the size of the aperture available for product dispensing is variable to allow the valve to adapt to different products.

According to a further aspect there is provided a packaging container having a self- closing valve as described herein.

The present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a plan ^' perspective view of a self-closing valve formed according to the present invention;

Figure 2 is an under plan perspective view of the valve of Figure 1 ;

Figure 3 is a side elevation of the valve shown in Figures 1 and 2;

Figure 4 is an under plan of the valve shown in Figure 1 to 3;

Figure 5 is a section of the valve shown in Figures 1 to 4; and

Figure 6 is a series of sections illustration the working of the valve shown in Figure 1 to 5.

Referring first to Figures 1 to 5, there is shown a self-closing valve generally indicated 10. the valve 10 is intended for use in combination with a container (not shown). The container is squeezable to expel product through the valve and is resilient so that after dispensing a negative pressure is generated within the container headspace to cause the valve to return to its as-moulded, retracted condition.

The valvelO is a unitary moulding of suitable flexible and resilient material, which in this embodiment is moulded silicon rubber.

The valve 10 has three main parts: a mounting ring 20; a valve head 30; and a connecting wall 40 which connects the mounting ring 20 with the valve head 30.

The mounting ring 20 forms a continuous marginal region around the valve and is of a generally triangular cross-section. The ring 20 allows the valvelO to be mounted in a housing which may be a container closure or a container or may be an intermediate mounting piece for a container closure or a container.

The valve head 30 is concave to the exterior of a container in use and is of progressively reducing thickness in the direction of its centre from the cylindrical face 32 which forms its outer periphery. The exterior face 34 of the valve head 30 is arcuate and the interior face 36 is arcuate except for a central flat 38.

The connecting wall 40 comprises a first rolling diaphragm portion 42 having a generally J-shape cross section and a second rolling diaphragm portion 44 also having a generally J-shaped cross section. The first section 42 is connected at one end to the mounting ring 20 and at the other end to a secondary valve head portion 46 which comprises a thickened region extending radially inwardly from the end of the portion

42. The opposite end of the secondary valve head portion 46 is connected to one end of the second portion 44. The other end of the portion 44 is connected to the valve head 30.

The discharge orifice of the valve 10 is defined by three slits 50, 55, 60. Each of the slits 50, 55, 60 has^' a short arm 51 , 56, 61 extending away from the centre point 65 and a longer arm 52, 57, 62. This means that whilst the arms 51 , 56, 61 extend from the centre point 65 to a point radially inwardly of the periphery of the valve head 30, the arms 52, 57, 62 extend into the connecting wall portion 44 and terminate in the secondary valve head 46.

The operation of the valve 10 will now be described in more detail with reference to Figure 6.

The valve is shown in its retracted, as-moulded position in Figure 6a. Figures 6b to 6e described below show an open "stage 1 " activation which in this embodiment is designed to accommodate dispensing of liquid and small particles.

When it is required to dispense product from a container through the valve 10 the container is squeezed by the user to generate an over-pressure within the container. In response to this pressure the valve head 30 rises through the centre of the valve structure. The connecting wall portion 44 is caused to double over and then extend rollingly, acting as a rolling diaphragm and in Figure 6b becomes inverted so that the valve head 30 sits within the secondary valve head 46 to define the intermediate position of the valve. Continued over pressure in the container results in the opening of the valve flaps as shown in Figure 6C. It will be noted that in this intermediate position the valve flaps open only along a diameter within the valve head; in other words the shorter arm portions of the slits open fully but the longer leg portions only open to an extent equivalent to the shorter leg portions so that the aperture does not extend into the connecting wall portion 44 in this stage.

When dispensing has finished and the over pressure is released the valve flaps return to their closed position as shown in Figure 6d. The valve head then returns to its original position as illustrated in Figure όe.

Figures 6f to 6o now illustrate a combined "stage 1 " and "stage 2" activation.

Figures 6f to 6h correspond to Figures όa to 6c in that the valve is shown to move to a stage 1 activation in which product is released in Figure 6h. If the pressure only ever reaches a lower pre-determined threshold, the valve 10 will never progress beyond stage 1 and will eventually return to the position shown in Figure 6f via the position shown in 6i. However, if larger particles present themselves at the exit of the container the pressure within the container will increase further and eventually will reach a second, larger predetermined pressure threshold. When this occurs the valve head 30 will now rise further within the valve structure as shown in Figure όj. This is possible because the connecting wall portion 42 can also undergo a doubling over and rolling action similar to that of the connecting wall portion 44. This means that the secondary valve head 46 can rise together with the valve head 30 (with the connecting wall portion 44 already in its inverted position). In Figure όj the connecting wall portion 44 has reached its fully inverted position and the valve head 30 is approximately level with and contained within the valve head 46.

Continued over pressure within the container causes venting of product. This occurs by the valve flaps opening as shown in Figure 6k which is comparable with Figure 6h. However, the secondary valve head 46 now also pivots with respect to the connecting wall portion 42 and extends upwardly as shown in Figure 6i so that both the valve head 30 and the valve head 46 now become active. In the position shown in 61 the slits become available for dispensing along their entire lengths so that the effective aperture size is increased and larger particles can be dispensed. When dispensing is complete and the over pressure is removed the valve can return from the fully open position shown in Figure 61. The valve flaps close and the valve head 30 returns to its closed position with the secondary valve head 46 pivoting back to its resting state as shown in figure 6m. The secondary valve head 44 then drops back to its resting position shown n Figure 6n before the valve head 30 drops to its resting position as shown in Figure 6o.

Claims

1. A self-closing valve for a packaging confainer, fhe valve comprising a marginal region by which the valve can be peripherally secured in the discharge opening of the container, a valve head having an openable dispensing aperture and being movable between a fully closed position in which it forms a seal and a fully open position in which a maximum usable aperture size is available for product dispensing, and a connecting wall arranged between the marginal region and the valve head, wherein the valve head is movable to one or more stable intermediate positions defining one or more intermediate aperture sizes for product dispensing.

2. A valve as claimed in Claim 1 , in which the aperture extends into the connecting wall.

3. A valve as claimed in Claim 1 or 2 in which the connecting wall includes one or more fulcrum points defining the or each intermediate position.

4. A valve as claimed in any preceding claim, in which at least part of the connecting wall has a resiliently flexible construction such when pressure within the container raised above a predetermined amount the valve head shifts outwardly and causes the wall to double over and extend rollingly.

5. A valve as claimed in any preceding claim, in which the aperture comprises one or more slits.

6. A valve as claimed in any preceding claim, in which the connecting wall comprises first and second portions joined together at a V-form elbow, the wall being of increased wall thickness at the elbow whereby during operation of the valve the elbow may keep its identity and act as resiliently as a spring for returning the valve head to its fully closed position.

7. A self-closing valve for a packaging container, the valve comprising a valve head having an openable dispensing aperture, in which the size of the aperture available for product dispensing is variable to allow the valve to adapt to different products.

8. A packaging container having a self-closing valve according to any preceding claim.