WO2016150734A1

WO2016150734A1 - Improvements in or relating to capping heads

Info

Publication number: WO2016150734A1
Application number: PCT/EP2016/055384
Authority: WO
Inventors: Frank VERDIJCK; Frederic Meyer
Original assignee: Obrist Closures Switzerland Gmbh
Priority date: 2015-03-20
Filing date: 2016-03-13
Publication date: 2016-09-29
Also published as: GB201504790D0; EP3271284A1

Abstract

A closure capping head (10) for applying a screw threaded closure (5) to a container, the head (10) comprising loading means (20, 30) for applying an axial load to a closure, in which the loading means can sequentially apply two or more different loads during closure application.

Description

IMPROVEMENTS IN OR RELATING TO CAPPING HEADS

The present invention relates generally to capping machines for affixing, for example, plastic screw closures on, for example, glass, plastic or metal containers for beverages or the like. More particularly it relates to the head portions of a capping machine which serve to rotate the plastic screw cap with respect to the container while pressing on the cap.

Standard capping heads are fitted with a spring which delivers the vertical load required to ensure the closure thread(s) are properly presented to the bottle thread(s) as the rotating capping head moves down a cam. In some systems the load also causes the bottle neck support ring to engage with "teeth" on the capping machine neck support plate, ensuring the bottle does not rotate whilst the closure reaches the designed angle of engagement.

The present invention seeks to provide improvements in or relating to capping head technology.

In an aspect of the present invention there is provided a closure capping head for applying a screw threaded closure to a container, the head comprising loading means for applying an axial load to a closure, in which the loading means can sequentially apply two or more different loads during closure application.

The loading means may comprise one or more springs. However, one spring having non-linear behaviour may alternatively or additionally used. The or one of the springs may exhibit non-linear behaviour.

In some embodiments a plurality of springs are provided, each spring exhibiting generally linear behaviour.

In some systems an initial loading step may be less than a subsequent loading step.

In some embodiments two loading steps are provided. More than two steps may be provided in other embodiments.

In some embodiments an initial loading step is lighter and a second step is heavier.

The present invention also provides a multi-spring capping head comprising a plurality of springs for sequentially applying different loads during cap application, whereby a non-linear capping force is applied.

The present invention also provides a capping head comprising loading means applying a load to a closure cap during cap application, in which the loading means applies a non-linear capping force.

The present invention also provides a double spring capping head comprising two springs for applying two different vertical loads during cap application. The present invention also provides a capping machine comprising one or more capping heads as described herein.

The present invention also provides a method of applying a closure onto a container comprising the steps of: a) using a capping head to provide an initial lighter loading on a closure as it is applied to a container; and b) subsequently using the capping head to provide a heavier loading on the closure.

The present invention also provides a method of applying a screw threaded closure to a container comprising the steps of: a) using a capping head to provide an initial lighter vertical generally linear loading on a closure as it is applied to a container; and b) subsequently using the capping head to provide a heavier generally linear loading on a closure. In some embodiments a double spring system is used. The purpose of the double spring system is to apply two or more different vertical loads during cap application.

A standard single spring head will typically have a total spring compression of between 3mm and 5mm. A single spring gives a linear increase of the vertical load as it follows the descent of the closure on the neck.

The double spring system of some embodiments first offers a light load (for example 5 to l OKg under 2mm compression) followed by a second high load (for example 15 to 25Kg under 2mm compression). The benefits of this two-step approach are as follows: The initial light load allows the closure and neck finish threads to engage smoothly (not forced) and also an immediate compression of the spring, which allows the closure to maintain controlled descent in case of threads jumping. Typically compression of between 3mm and 7mm may be required for optimum application of closures.

The first step (soft spring) may be limited to less than 3mm to ensure that the second step (hard spring) has the ability to contribute to the capping process.

The second heavier load allows the teeth of the capper neck supports (anti-rotation devices) to "bite" into the neck support ring of the bottles, stopping the rotation of the bottle under standard application conditions (torque, rotation speed). Embodiments of the present invention may use sequential application of loads, for example a first load being a soft spring; when it has compressed the specified distance, the second load is additive load from the first and second springs.

The vertical loads may be optimized by spring length and load according to capping machine design features and closure/neck finish specifications.

In some embodiments the present invention may be used to help reduce the number of "cocked" caps. For example the present invention may comprise: I . To have a light spring that will be compressed immediately as soon as the closure touches the neck.

This compression would then allow the chuck to follow down the closure in case it would go quickly down due to thread snapping or other; and thread engagement happens under soft vertical pressure.

2. To have a second spring to be able to stop the rotation of the bottle due to the screwing torque.

Different aspects and embodiments of the invention may be used separately or together.

Further particular and preferred aspects of the present invention are set out in the accompanying independent and dependent claims. Features of the dependent claims may be combined with the features of the independent claims as appropriate, and in combination other than those explicitly set out in the claims.

Other aspects, objectives and advantages of the present invention will appear more clearly on reading the following description of several embodiments thereof, given by way of non-limiting examples and with reference to the appended drawings. The figures are not necessarily to scale for all the elements represented so as to improve the readability thereof. In the remainder of the description, for the sake of simplicity, identical, similar or equivalent elements of the various embodiments bear the same numerical references. The present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:

Figure I is a section of capping head formed in accordance with the present invention; and

Figure 2 is a chart showing the loading applied by the capping head of Figure I .

Example embodiments are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein. Accordingly, while embodiments can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments are consistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

The terminology used herein to describe embodiments is not intended to limit the scope. The articles "a," "an," and "the" are singular in that they have a single referent, however the use of the singular form in the present document should not preclude the presence of more than one referent. In other words, elements referred to in the singular can number one or more, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes," and/or "including," when used herein, specify the presence of stated features, items, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, items, steps, operations, elements, components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealized or overly formal sense unless expressly so defined herein.

Referring now to Figures I and 2, in this embodiment a double spring system is used. The purpose of the double spring system is to apply two or more different vertical loads during application of a cap 5.

In Figure I there is shown a capping machine I with a capping head 10 having a "light" spring 20 (blue), and a heavy spring 30 (green). In this embodiment the distance over which the light spring is effective (pink) is approximately 2mm.

The double spring system first offers a light load (for example 5 to l OKg under 2mm compression) followed by a second high load (for example 15 to 25Kg under 2mm compression). The initial light load allows the closure and neck finish threads to engage smoothly (not forced) and also an immediate compression of the spring, which allows the closure to maintain controlled descent in case of threads jumping. Typically compression of between 3mm and 7mm is required for optimum application of closures.

The first step (soft spring) is limited to less than 3mm to ensure that the second step (hard spring) has the ability to contribute to the capping process.

For some applications, for example PET container, the second heavier load allows the teeth of the capper neck supports (which are anti-rotation devices) to "bite" into the neck support ring of the bottles, stopping the rotation of the bottle under standard application conditions (torque, rotation speed).

For glass or metal containers the anti-rotation systems may be side belts acting on the container or another system. The requirement for light and heavy top loads from double springs remains the same. This embodiment is therefore based on sequential application of the loads. The first load is the soft spring, but when it has compressed the specified distance, the second load is additive load from the first and second springs.

Although illustrative embodiments of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is understood that the invention is not limited to the precise embodiments shown and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.

Claims

A closure capping head for applying a screw threaded closure to a container, the head comprising loading means for applying an axial load to a closure, in which the loading means can sequentially apply two or more different loads during closure application.

A head as claimed in claim I , in which the loading means comprises one or more springs.

A head as claimed in claim 2, in which the or one of the springs exhibits nonlinear behaviour.

4. A head as claimed in claim 2, in which a plurality of springs are provided, each spring exhibiting generally linear behaviour.

5. A head as claimed in any preceding claim, in which an initial load is less than a subsequent load. 6. A head as claimed in any preceding claim, in which two loading steps are provided.

A head as claimed in claim 6, in which an initial loading step is lighter and second step is heavier.

8. A multi-spring capping head comprising a plurality of springs for sequentially applying different loads during cap application, whereby a non-linear capping force is applied. 9. A capping head comprising loading means applying a load to a closure cap during cap application, in which the loading means applies a non-linear capping force.

10. A double spring capping head comprising two springs for applying two different vertical loads during cap application.

I I . A closure capping head for applying a screw threaded closure to a container, the head comprising loading means for applying a load to a closure, in which the loading means can sequentially apply two or more different loads during closure application.

1 2. A head as claimed in claim I I , in which two or more loading members are provided for sequential application of the loads. 1 3. A head as claimed in claim 1 2, in which sequential loading provided the members is additive.

14. A head as claimed in any of claims I I to 1 3, in which first and second springs are provided for applying the load, a first load is initially provided by a softer spring, and when the softer spring has compressed a specified distance the second load is an additive load from the first and second springs.

1 5. A capping head substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

1 6. A capping machine comprising one or more capping heads as claimed in any preceding claim.

1 7. A method of applying a closure onto a container comprising the steps of: a) using a capping head to provide an initial lighter loading on a closure as it is applied to a container; and b) subsequently using the capping head to provide a heavier loading on the closure.

1 8. A method of applying a screw threaded closure to a container comprising the steps of: a) using a capping head to provide an initial lighter vertical generally linear loading on a closure as it is applied to a container; and b) subsequently using the capping head to provide a heavier generally linear loading on a closure.

1 9. A method substantially as hereinbefore described with reference to,

shown in, the accompanying drawings.