Resealable opening device and package comprising such an opening device

An opening device for a flexible package having an opening portion defined by two side walls and a width, the opening device intended to be disposed in the opening portion of the package adjacent to an opening, formed upon initial opening of the package, for opening and closing thereof. The opening device comprises a thin-walled first body with a contact surface and a first application surface opposite thereto for allowing application of the first body in the opening portion to a first of the two side walls. The first body is maneuverable, by folding about a first folding axis, between a basic position and a sealing position. In the sealing position, the contact surface has sub portions directly facing each other. A locking member is designed for releasable locking of the body in the sealing position.

TECHNICAL FIELD

The present invention relates to a resealable opening device for a flexible package and to a package comprising such an opening device.

BACKGROUND OF THE INVENTION

There are a large number of different goods which are packed in flexible packages produced from a film material.

The packages may house particulate goods, such as crisps, peanuts or coffee beans, and in this case often have a so-called pillow shape.

Alternatively, the packages may house liquid goods, such as milk, water or wine, and are here normally of the so-called stand-up pouch type, also referred to as collapsible-type packages. Packages of the stand-up pouch type may, of course, also be used for particulate goods.

Packages or containers of this flexible type are normally opened by the removal of an end tab or corner portion. Alternatively, they can be opened by a user pulling apart the side walls of the package in order thereby to break an upper transverse seal of the package.

Common to these flexible packages is that there is often a need to be able to reseal the package once it has been opened. By resealing the package, the risk of accidental spillage of the content of the package is reduced, whilst the resealing often has a positive effect on the shelf life of the content.

This resealing can be realized with the aid of clips, screw caps, rubber bands, tapes, etc. It has nevertheless proved difficult to provide an opening device which is cheap, reliable, user-friendly and, moreover, relatively easy to apply to the package in connection with the filling thereof. Opening devices for flexible packages are known, for example, from U.S. Pat. Nos. 3,815,810, 6,296,388 and WO2004/092022.

U.S. Pat. No. 3,815,810 discloses an opening device in the form of a thin-walled body which is applied to a side wall of the package. For resealing of the package, an end section comprising an opening is folded, and the end section is locked in the folded state by means of tabs of the body which are folded up over the said end section.

U.S. Pat. No. 6,296,388 discloses a foldable thin-walled body which is intended for application inside an opening of the package.

WO2004/092022 discloses various types of opening devices of the zip-lock type, which are stamped in place in the package adjacent to its opening.

It can thus be seen that there is a need for an improved resealable opening device for flexible packages.

SUMMARY OF THE INVENTION

In view of the above, it is an object of the present invention to provide an improved resealable opening device for a flexible package.

It is also an object of the invention to provide a flexible package comprising a resealable opening device of this kind.

According to the present invention, a resealable opening device having the distinguishing features defined in claim1and a package having the distinguishing features defined in claim21are thus provided. Embodiments emerge from the sub-claims dependent on the respective main claims.

More precisely, according to the present invention, an opening device for a flexible package having an opening portion which is defined by two side walls and has a width is provided, which opening device is intended to be disposed in the opening portion of the package adjacent to an opening, formed upon initial opening of the package, for opening and closing thereof, which opening device comprises a thin-walled first body with a contact surface and a first application surface opposite thereto for allowing application of the said first body in the opening portion to a first of the said two side walls, and a locking member. The first body is manoeuvrable, by folding about a first folding axis, between a basic position and a sealing position, in which sealing position the said contact surface has sub portions directly facing each other. Said sub portions adjoin each other along a boundary portion which is designed to extend along substantially the full width of the opening portion, and the said locking member is designed for releasable locking of the body in the said sealing position. The locking member is disposed in at least one of the sub portions of the contact surface and is designed to act between the said sub portions in order to achieve said releasable locking.

An improved, resealable opening device for a flexible package is hereby provided. The opening device comprises a foldable first body and a locking member which allows locking of the first body in the folded position, i.e. the sealing position, and is thus relatively easy and cheap to produce. Since the body of the opening device is thin-walled and is also foldable about the first folding axis, the body can be made substantially flat and is hence relatively easy to apply in the opening portion of a package. The inventive opening device also allows reliable resealing of a flexible package. The opening device is here arranged in the opening portion of the flexible package by placing the application surface of the body against one of the two side walls of the package which define the opening portion. The opening device can be applied to the package with the aid of an adhesive or by a heat treatment process or the like. By manoeuvring the first body of the opening device from its basic position into its sealing position, i.e. by folding the first body about the first folding axis, it becomes possible to fold an end section of the opening portion over the said first folding axis, whereby the package is resealed. By suitably adapting the length of the first body in relation to the width of the opening portion, it is possible to achieve resealing with a high level of reliability. More precisely, it is assured that the sub portions adjoin each other along said boundary portion, which is designed to extend along substantially the full width of the opening portion. Preferably, it is assured that the length of the first body somewhat exceeds the width of the opening portion, whereby a substantially liquid-tight resealing can be achieved.

According to one embodiment, a first hinge joint having an extent which coincides with said first folding axis may be configured in the said first body. It is hereby ensured that the folding about the first folding axis during manoeuvring of the first body from the basic position into its sealing position is well-defined. The first hinge joint can here have a v-shaped or w-shaped cross section. In particular, the use of a w-shaped cross section on the first hinge joint can make it possible to achieve such tight resealing that a package housing a liquid content can be turned up and down without leakage after it is resealed.

According to another embodiment of the present invention, the said locking member may form a spacer element which mutually separates the sub portions of the contact surface in the sealing position of the first body. The manoeuvring of the first body of the opening device from the sealing position into the basic position, which corresponds to opening of the package from the resealed state, is hereby facilitated. The spacer element namely enables the finger of a user to be introduced between the two mutually facing sub portions in order to prise these apart and thereby release the locking member.

According to another embodiment of the present invention, the said first body may be manoeuvrable between the said basic position and an opening position by folding about a second folding axis extended transversely to the said first folding axis. By manoeuvring the first body into the opening position, it becomes possible to arrange the package in an opened-up state which facilitates dispensing of the content of the package. A second hinge joint having an extent which coincides with the said second folding axis can here be configured in the said first body. It is hereby ensured that the folding about the second folding axis during manoeuvring of the first body from its basic position into its opening position is well-defined. The application surface may have, in the opening position of the first body, two sub portions angled relative to each other.

According to a further embodiment of the present invention, the opening device further comprises a second body extended along a longitudinal axis and having a second application surface for allowing application of the second body in the opening portion to a second of the said two side walls, wherein the second body is manoeuvrable between an unfolded position and a folded position by folding about a third folding axis, the second body being intended for manoeuvring into the said folded position in connection with manoeuvring of the first body into its opening position. The first and second body of the opening device are thus both folded in connection with opening of the package into its opened-up state and it hereby becomes possible to achieve a well-defined opening with a bottom corner having a lower opening angle which is sufficiently large to ensure that product residues, should these be fluid, are not detained in the opening portion under the influence of surface tension effects following completed dispensing of the content by a pouring process. The surface tension effects can vary in dependence on the product, so that the lower opening angle may be adapted to the particular type of product.

By suitable placement of the second body on the package and suitable configuration of the same, it can be assured that the second body has no bearing when the first body is manoeuvred from its basic position into the sealing position for resealing of the package. In particular, the said first body may have a first width and the said second body can have a second width, wherein the second width is less than half the first width. It hereby becomes possible to apply the second body to the package such that the package can be freely resealed by means of the first body.

According to another embodiment, the said first body may have a first length and the said second body may have a second length, wherein the second length is equal to or less than the first length. It hereby becomes possible to assure that the first and the second body can be freely manoeuvred into the opening position and second position respectively of the package for arrangement of the package in its opened-up state.

According to one embodiment, a third hinge joint having an extent which coincides with the said third folding axis may be configured in the said second body. It is hereby ensured that the folding about the third folding axis, when the second body is manoeuvred from its unfolded into its folded position, is well-defined.

One, some or all of the above-specified hinge joints may have a v-shaped or w-shaped cross section.

According to a further embodiment of the present invention, the said locking member may be designed for point locking. Alternatively, the locking member may be designed for linear locking.

According to a further embodiment of the opening device, the said locking member may be designed for mechanical locking. The locking member may be designed for mechanical locking by snap action. As an alternative to mechanical locking, the said locking member may be designed for locking with the aid of an adhesive.

According to another embodiment of the present invention, the body of the opening device may be made of a plastics material, such as PET, having a thickness within the range of 0.1-1 mm.

According to yet another embodiment, the application surface may be provided with an adhesive layer comprising a hot melt adhesive. Hereby, an opening device is provided which is non-sticky in room temperature and thus easy to handle. The adhesive layer of the opening device may be activated by exposure to heat in order to allow application on a package. The adhesive layer preferably covers the application surface. By the adhesive layer covering the entire application surface, it may be ensured that an end section of the package is properly folded upon manoeuvring the first body to the sealing position.

The adhesive layer may have an undulated surface. Hereby the capacity of the adhesive layer to store heat in connection with exposure to heat is enhanced, which may be beneficial in connection with application of the opening device on a package.

According to the present invention, a flexible package having an opening portion defined by two side walls, comprising an opening device which is disposed in the opening portion adjacent to an opening, formed upon initial opening of the package, for opening and closing thereof, which opening device comprises a thin-walled first body with a contact surface and a first application surface opposite thereto by which the first body is fastened to an external surface of a first of the said side walls of the package, and a locking member, is also indicated. The first body is manoeuvrable, by folding about a first folding axis, between a basic position and a sealing position, in which sealing position said contact surface has sub portions directly facing each other, and the locking member is disposed in at least one of the sub portions of the contact surface and is designed to act between the said sub portions in order to achieve releasable locking of the body in the said sealing position. The first folding axis of the first body is oriented parallel with said opening, and the package is manoeuvrable into a resealed state in which an end section of the opening portion comprising the said opening is folded about the said first folding axis by manoeuvring of the first body into the said sealing position.

According to one embodiment of the inventive package, the first body of the opening device may be manoeuvrable, by folding about a second folding axis extended transversely to the said first folding axis, between the said basic position and an opening position, wherein the package may be arranged in an opened-up state in which the side walls in the opening portion are separated by manoeuvring of the first body into the said opening position.

According to a further embodiment, the opening device further may comprise a second body extended along a longitudinal axis and having a second application surface by which the second body is fastened to an external surface of a second of the said two side walls, which second body is manoeuvrable, by folding about a third folding axis, between an unfolded position and a folded position, wherein the package may be arranged in the opened-up state by manoeuvring of the second body into the folded position in connection with manoeuvring of the first body into the opening position.

According to yet another embodiment, the first body and the second body may be disposed in the opening portion on the first side wall and second side wall respectively of the package such that the second body is situated within a region defined by the contour of one of the said sub portions of the first body. It is hereby ensured that the first body can be manoeuvred into its sealing position so as to reseal the package without influence from the second body.

According to another embodiment, the second folding axis of the first body may be parallelly displaced in relation to the third folding axis of the second body. By virtue of the fact that the first and the second body are applied with respectively the second and third folding axis parallelly displaced with respect to each other, opening of the package into its opened-up state is facilitated, since the folding is hereby controlled such that the bodies are folded in different directions.

The advantages which have been specified above with reference to the inventive opening device are in relevant parts also applicable to the inventive flexible package.

Terms in the claims should generally be interpreted according to their normal meaning within the technical field, unless otherwise expressly stated. All references to “a/the [element, device, component, member, step]” should be interpreted as a reference to at least a presence of the said element, device, component, member, step, etc., unless otherwise expressly stated. The steps of any method which is described herein do not have to be performed in exactly the described order, unless otherwise expressly stated.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention relates to an opening device for a flexible package and to a flexible package comprising such an opening device.

By a flexible package is meant a package or container which is made of a flexible material in the sense that the material is pliable. A flexible package of this kind may thus be made of a single-layered or multi-layered film material. The film material may comprise layers of plastic, such as PE, PP, PET, EVOH, and/or aluminium foil. Layers of plastic such as PE or PP may also comprise a filler, such as a mineral material.

InFIGS. 1aand 1b, to which reference is made, an embodiment of the inventive opening device1is illustrated.

The opening device1comprises a first body4extended along a first folding axis2, and a locking member5disposed on the body4.

The first body4can be made of a rigid, yet pliable plastics material, such as PET plastic, and can have a thickness within the range of 0.1-1 mm.

As in the embodiment shown, the first body4can have an elongated shape having parallel long sides, and short sides which are symmetrically bevelled.

According to the embodiment shown, the corners of the first body4are rounded to avoid scratch injuries to a user during handling of the inventive opening device1.

It will be appreciated that the first body can be given a number of other configurations and that the first body can thus be given a rectangular shape or be provided with asymmetrically bevelled short sides, such as chamfered or straight cut short sides.

The first body4is manoeuvrable between a basic position for allowing opening of the package and a sealing position corresponding to a resealed state of the package, in which sealing position the said first body4is folded about the said first folding axis2.

In the embodiment shown, a first hinge joint6having an extent which coincides with the said first folding axis2is configured in the said first body4. The first hinge joint6has a w-shaped cross section, as can be seen from the detached partial enlargement inFIG. 1b, but it will be appreciated that the first hinge joint6can be configured differently, such as with a v-shaped cross section.

In the embodiment shown, it is thus the first hinge joint6which allows a well-defined folding about the first folding axis2for manoeuvring of the first body4into the said sealing position.

The first body4has a contact surface8, on which the said locking member5is disposed, and an application surface9, facing away from the contact surface8, by which the said opening device1can be applied to the package.

The application surface9may be partly or preferably entirely covered by an adhesive (not shown) for enabling application of the opening device1to the package. The adhesive may be in the form of an adhesive layer in the form of a hot melt adhesive, also known as hot glue. In connection with application of the opening device9to the package, the adhesive layer may be activated by exposure to heat.

The contact surface8has two sub portions10a,10b, which are disposed on one side each of the first hinge joint6and which, when the first body4is in the said sealing position, are directly facing each other. The locking member5, which according to the present invention is disposed in at least one of the said sub portions10a,10b, is designed, when activated, to act between the said sub portions10a,10bso as to detain the first body4in the said second position. By virtue of the fact that the sub portions10a,10bof the contact surface8are directly facing each other in the sealing position of the first body4, it is ensured that nothing hinders the locking member5from acting between the said sub portions10a,10b.

The sub portions10a,10bof the contact surface8are illustrated schematically inFIG. 3a, to which reference is now made.

In the embodiment shown, the locking member5is configured in one piece with the first body4and is designed for mechanical and point locking of the body4in the said sealing position. More precisely, the locking member5comprises two male members11, which by snap action can be brought into releasable locking engagement with their respective female member12. Each pair of male and female members11,12thus forms a push-button-like construction and the locking member5is thus activated by the pairs of male and female members11,12being pressed one against the other in connection with the manoeuvring of the first body4into its sealing position.

The male members11are disposed on a first10aof the said sub portions of the contact surface8and the female members12are disposed on a second10bof the sub portions of the contact surface8. It will be appreciated that the number of pairs of male and female members11,12may also be less than or more than two.

It will further be appreciated that the locking member5may be configured differently. For example, the locking member may be designed for mechanical and linear locking of the body in its sealing position. Such a locking member may comprise an elongated male member, which by snap action can be made to engage with an elongated female member.

The locking member may alternatively be configured separately in relation to the first body. For example, the locking member may be configured in the form of an adhesive which is disposed on one of the two sub portions of the contact surface, which adhesive releasably adheres to the second of the two sub portions of the contact surface by manoeuvring of the first body into its sealing position.

The embodiment shown of the inventive opening device1is further manoeuvrable between the said basic position and an opening position, corresponding to an opened-up state of the package, by folding about a second folding axis3extending transversely to the said first folding axis2. A second hinge joint7having an extent which coincides with the second folding axis3is configured in the said first body4. The second hinge joint7can have a v-shaped cross section.

As in the embodiment shown, the second folding axis3can have an extent at right angles to the extent of the first folding axis2, but it will be appreciated that the second folding axis3can also extend transversely to the first folding axis2with other angular relationships.

The second hinge joint7is configured such that the application surface9has, in the opening position of the first body4, two sub portions13a,13bangled relative to each other.

The sub portions13a,13bof the application surface9are illustrated schematically inFIG. 3b, to which reference now also is made.

The first hinge joint6and the second hinge joint7thus allow well-defined folding of the first body4in opposite directions. The first hinge joint6allows the first body4to be folded in such a direction that the sub portions10a,10bof the contact surface8are angled and are also turned towards each other, whilst the second hinge joint7allows the first body4to be folded in such a direction that the sub portions13a,13bof the application surface9are angled relative to each other.

The configuration of a first and a second hinge joint6,7in the said first body4results in the first body4acquiring a bistable character. When the first body4is in its basic position, the first hinge joint6thus allows folding about the first folding axis2, at the same time as the second hinge joint7allows folding about the second folding axis3. The bistable character of the first body4means, however, that once folding has been initiated about one of the first and the second folding axes6,7, i.e. once the first body has been manoeuvred from its basic position, folding about the second of the first and second folding axes6,7is not allowed.

Should the second hinge joint extend transversely to the first hinge joint at an angle different from 90°, it becomes possible to assure that the bistable character of the first body is maintained also in the folded state. In particular, folding about the second folding axis7is precluded when the first body is folded about the first folding axis6and is in the sealing position.

InFIG. 3a-c, to which reference is now made, the first body4of the inventive opening device1is illustrated in its three different positions.

InFIG. 3a, the first body4of the opening device1is shown in its basic position, which corresponds to an unaffected position of the first body4. The basic position represents a position which allows resealing or opening-up of the package, i.e. manoeuvring of the first body4into either its sealing position or its opening position.

InFIG. 3b, the first body4of the opening device1has been manoeuvred from the basic position into the said sealing position by folding about the first folding axis2. The first hinge joint6ensures that the folding is well-defined about the said first folding axis2.

It will be appreciated that the opening device1could also be configured without the first hinge joint6. The first body4of the opening device1is here dimensioned such that it has the necessary rigidity, whilst it can still be bent about the first folding axis2. The absence of a first hinge joint6means, however, that the folding is not as well-defined.

The locking member5is configured such that its pair of male and female members11,12engage with each other under snap action and releasably lock the first body4in the sealing position. The sealing position represents a resealed state of the package.

As can be seen fromFIG. 3a, each male member11is configured in the form of a projection and each female member12is formed by an opening in a protrusion. Both the projections and the protrusions jut out from the contact surface8and the locking member5hereby forms a spacer element14which mutually separates the sub portions10a,10bof the contact surface8when the male members11engage with the female members12in the sealing position of the first body4. This separation is illustrated inFIG. 3bby means of the distance D. By virtue of the fact that the sub portions10a,10bare separated from each other in the sealing position of the first body4, a user can easily introduce a finger between the said sub portions10a,10bin order to release the locking member5and open the opening device1.

InFIG. 3c, the first body4of the opening device1has been manoeuvred from the basic position into the said opening position by folding about the second folding axis3. The second hinge joint7ensures that the folding is well-defined about the said second folding axis3. The third position represents an opened-up state of the package.

It will be appreciated that the opening device1could also be configured without the second hinge joint7. The first body4of the opening device1is here dimensioned such that it has the necessary rigidity, whilst it can still be bent about the second folding axis3. The absence of a second hinge joint7means, however, that the folding is not well-defined. Should an inventive opening device1without a second hinge joint7be applied adjacent to an opening in a flexible package containing a liquid product, the manoeuvring of the first body of the opening member from its basic position into its opening position could be realized by the user performing a pouring motion, whereby the product pressure opens up the opening in the flexible package and thus acts upon the first body of the opening device such that this is bent about the second folding axis.

The inventive opening device1allows resealing of flexible packages, and the opening device will be described below with reference to a first embodiment of an inventive package15according toFIG. 4a-4e, to which reference is now made.

The first embodiment is a flexible package15of the collapsing type, also referred to as a stand-up pouch. This type of package is suitable for liquid products and, as shown in the figures, can comprise a gas-filled handle.

An inventive opening device1of the type which has been described above with reference toFIGS. 1aandbandFIG. 3a-cis applied to the package15in an opening portion16of the package, which opening portion16is formed by two opposing side walls17of the flexible package15in a corner section of the same.

The opening portion16of the flexible package comprises in the unopened state of the package an end tab18, which for initial opening of the package is separable from the package15by detachment along a separation line19. The package15is shown in its unopened state inFIG. 4a.

The first body4of the opening device1is disposed on one of the said opposing side walls17adjacent to the end tab18of the opening portion16, and, more precisely, is disposed on that side of the separation line19situated opposite the end tab18, adjacent to and parallel with this same separation line.

The separation line19may be configured as an initiation for facilitating detachment of the end tab18from the package15. The initiation may comprise treated and untreated portions. The treated portions may be configured as weakenings, perforations or the like.

The opening device1can be applied to the package15by the use of adhesive or by a heat-sealing process, or by some other suitable process. As mentioned above, the application surface of the opening1device may comprise an hot melt adhesive layer in order to facilitate application.

By virtue of the fact that the opening device is produced separately from the package, production of preformed packages which can be distributed in roll form to a filling plant, such as a dairy, is allowed. Such a roll of preformed packages may then be used in a filling machine to produce filled packages. The inventive opening device may in this case be applied to the package in the filling machine. The opening device may be applied to the package before, during or after the filling thereof.

InFIG. 4b, the end tab18has been separated from the package15for initial opening of the same, whereby an opening20is formed in the opening portion16, which opening20allows a content housed in the package15to be poured out or dispensed. As can be seen from the figure, the opening device1is disposed adjacent to and parallel with the said opening20.

In the figure, the opening device1is illustrated with its first body4in the basic position, which, as previously described, allows opening of the package15.

InFIG. 4c, the package15is illustrated in an opened-up state. The first body4of the opening member1has here been manoeuvred from the basic position into the opening position by folding about the second folding axis3, which folding is controlled by the second hinge joint7. The manoeuvring is expediently realized by the user, with a thumb and index finger grip, pressing the two opposing short sides of the opening device1one against the other such that folding takes place about the second folding axis3. By virtue of the fact that the opening device1is disposed on one side wall17of the package15, part of this will accompany the opening device1during folding about the second folding axis3, and will be separated from the second side wall17, which can be made to bulge in the opposite direction. FromFIG. 4c, it can be seen how the opening20in the opening portion16is opened up and acquires a well-defined pouring area when the first body4of the opening device1assumes the said opening position.

It will be appreciated that the opening position does not represent an exactly defined position, but is constituted by a position which can vary from one time to another. The purpose of the opening position is to achieve a pouring area for the opening20in the opening portion16. It will also be appreciated that the first body may able to assume and maintain the opening position in response to a force load. This force load can be exerted by the product housed in the package, in connection with the performance of a pouring motion when the product reaches the opening portion16of the package.

Due to the bistable nature of the opening device1, folding of the first body4of the opening device1about the said first folding axis2is not allowed as long as the first body4of the opening device1is in the opening position. It should here be noted that the first body4is not fully folded about the second folding axis3in the third position, which is also why the bistable character is maintained in the opening position despite the fact that the second hinge joint7, in the embodiment shown, extends transversely to the first hinge joint6at a right angle.

InFIGS. 4dand 4e, the process for resealing the opened package15is shown. To begin with, the first body4of the opening device1is returned from the opening position into the basic position by folding about the second folding axis3(not shown). After this, the first body4is folded about the first folding axis2, and inFIG. 3dit is shown how the folding has been started and inFIG. 3ethe first body4is shown in the sealing position following completed folding. The locking member5has here been activated and thus ensures that the first body4is detained in the said sealing position.

Due to the bistable nature of the opening device1, folding of the first body4of the opening device1about the said second folding axis3in connection with the folding of the first body4about the first folding axis2is not allowed. It should here be noted that the first body4is fully folded about the first folding axis2in the sealing position. Since the second hinge joint7, in the embodiment shown, extends transversely to the first hinge joint6at a right angle, the bistable character of the first body may cease when the first body assumes the sealing position.

Since the opening device1and its first body4are disposed on one side wall17of the package15, part of this side wall17will be folded, together with the opening device1, in the course of the folding about the first folding axis2and will thus also drag with it part of the second side wall17. Consequently, manoeuvring of the first body4of the opening device1from the basic position into the sealing position causes an end section comprising the said opening20in the opening portion16to be bent over the first folding axis2, with the result that the package15is resealed, as can thus be seen fromFIG. 4e.

As in the embodiment shown, the opening device1can be configured such that it has a length L which substantially conforms to a width W of the opening portion16in the same position, that is to say measured along a line coinciding with the second folding axis2. More precisely, the sub portions10a,10bof the contact surface8of the first body4adjoin each other along a boundary portion extending along substantially the full width W of the opening portion. Preferably, the length of the opening device1somewhat exceeds the width W of the opening portion16. It is hereby ensured that a relatively tight resealing is achieved, which has a positive effect on the taste and shelf-life of the product enclosed in the package15. A tight resealing further minimizes the risk of spillage if the package were to overturn.

The first hinge joint6configured in the first body4of the opening device1may have, as previously described, a w-shaped cross section. The advantage with a first hinge joint6which is configured in this way will be described below in greater detail with reference toFIG. 5a-5c, which schematically show the inventive opening device1applied to one side wall17of the package15adjacent to the opening20in the opening portion16.

The first hinge joint6of the first body has a w-shaped cross section, which can be said to comprise two legs21and an intervening ridge22, as can be clearly seen from the detached partial enlargement inFIG. 5a, in which the w-shaped cross section is marked. The “free” ends of the legs21of the cross section connect to one half each of the first body4of the opening device1. The w-shaped cross section is oriented such that the ridge22is facing towards the side wall17of the package15.

InFIG. 5a, the opening device1is illustrated with its first body4in the basic position.

InFIG. 5b, it is illustrated how a user has started acting upon the opening device1to manoeuvre the first body4from its basic position into the sealing position, wherein the first hinge joint6controls the folding about the first folding axis2. It can here be seen how that part of the first body4which is folded drags with it the side wall17directly connected thereto, which in turn drags with it the second of the side walls17. By folding of the first body4about the first folding axis2, the said end section of the opening portion16will consequently be folded over the said first folding axis2.

InFIG. 5c, it is illustrated how the first body4of the opening device1has been manoeuvred into the sealing position, in which the locking member5has been activated in order to maintain the said sealing position. The side walls17, and the thereby defined opening portion16, are folded about the first folding axis2. From the detached partial enlargement inFIG. 5c, it can be seen how the side walls17are stretched and are pressed against the ridge22of the w-shaped cross section of the first hinge joint6when the first body4assumes the said sealing position. This stretching and pressing helps to increase the reliability of the resealing capability of the opening device1.

The hinge joints may be formed by a thermo forming operation. The w-shape of the first hinge joint6may be accomplished such that material is moved from the recesses towards the ridge, which consequently can be made to protrude from the contact surface8of the first body4.

In the figures, the legs of the w-shaped cross section are angled. However, the legs may be perpendicular towards the contact surface8. As a consequence, no material will in this case be displaced in a direction from the ridge in connection with forming of the first hinge joint by a thermo forming operation.

Practical trials have shown that the resealing can be made sufficiently tight that a package housing a liquid product, when the package has been opened and resealed with the aid of the inventive opening device1, can be turned up and down without leakage.

It will be appreciated that the inventive opening device1does not just need to be used in combination with packages of the above-described type.

It is thus conceivable to use the opening device together with a flexible pillow-shaped package. According to a second embodiment of an inventive resealable flexible package15′, which second embodiment is illustrated inFIG. 6a-6b, an inventive opening device1is disposed in an opening portion16, which is formed by two opposing side walls17of the flexible package15′ in a corner section of the same.

The opening device1, which, as previously, comprises a first body4, is more precisely disposed on one of the said opposing side walls17adjacent to an end tab18of the opening portion16, which end tab18is separable from the package15′ by detachment along a separation line19. The opening device1is disposed on that side of the separation line19situated opposite the end tab18, adjacent to and parallel with this same separation line.

A flexible resealable package15′ according to the said second embodiment is well suited to a particulate content, such as peanuts or sweets. It will be appreciated, however, that this type of package can also hold other types of content, such as a liquid content.

InFIG. 6a, the package15′ is shown in an unopened state, and inFIG. 6bthe end tab18has been separated along the indicated separation line19, which enables the package15′ to be opened up by manoeuvring of the opening device1into the opening position of the first body4in a manner corresponding to that which has been described above in connection with the first embodiment of a flexible resealable package15, or by manoeuvring of the opening device1into the sealing position of the first body4in order to reseal the package15′, as is also shown inFIG. 6b.

It will further be appreciated that the inventive opening device1does not necessarily have to be applied in an opening portion forming part of a corner section of the package. InFIG. 7a-b, to which reference is now made, a flexible resealable package15″ according to a third embodiment is illustrated.

The package15″ has an opening portion16defined by two opposing side walls17of the package15″. The opening portion16comprises an end tab18forming a top portion of the package15″, which end tab18is separable from the package15″ along a separation line19. The opening device1comprising a first body4is disposed in the opening portion16adjacent to its end tab18and is parallelly arranged with respect to the said separation line19.

The opening device1has a length L which substantially conforms to the width W of the opening portion16measured along a line coinciding with the second folding axis2. It will be appreciated that, for a rectangular package such as that which is shown in the figures, this width W corresponds to the width of the package itself. The package15″ according to the said third embodiment is shown inFIG. 7ain an unopened state and inFIG. 7bin a resealed state.

The first body4of the opening device1has in the embodiment shown a rectangular shape, i.e. the first body4has straight cut short sides.

The first body4of the opening device1also has two further hinge joints35,36, which are each disposed in a respective end portion of the first body4. The further hinge joints35,36extend transversely to the first hinge joint2. The purpose of the further hinge joints35,36is to facilitate the manoeuvring of the inventive opening device. The hinge joints35,36delimit, more precisely, a gripping tab at the respective end of the first body4, which gripping tabs can be gripped by a user in connection with manoeuvring of the first body into its opening position.

As can be seen from the figure, the first body does not in the embodiment shown have a second hinge joint which controls the folding about the second folding axis in connection with manoeuvring of the body into its opening position.

It will also be appreciated that the opening portion16does not need to comprise a separable end tab. InFIG. 8a-8c, to which reference is now made, a fourth embodiment of an inventive resealable flexible package15″′, which comprises an opening portion16defined by two opposing side walls17of the package15″′, is illustrated. The opening portion16forms part of a top portion of the package15″′ and is openable by separation of the side walls17of the package15″′ in order to break a transverse edge seal23along which the two side walls17of the package15″′ are mutually connected. The opening device1is disposed in the opening portion16, parallel with the said edge seal23.

The package15″′ according to the said fourth embodiment is shown inFIG. 8ain an unopened state, in8bin an opened-up state and inFIG. 8cin a resealed state. In this embodiment, too, of the present invention, the opening device is illustrated with two further hinge joints35,36of the first body4, which further hinge joints35,36delimit their respective gripping tab in order to facilitate the manoeuvring of the opening device1.

A process for producing inventive opening devices will be described below with reference toFIG. 9, which shows a production line24comprising a punching station25, a forming station26and a separating station27. In the embodiment shown, the forming station26comprises a heating unit28and a pressing unit29.

The material from which the opening devices shall be produced is supplied in the form of a roll30from which a material web31is unrolled and is led to the various stations.

The material web31initially reaches the punching station25, which in the embodiment shown comprises a rolling press32which engages with the side edges of the material web31in order to punch out a profile which meets the desired shape of the short sides of the opening devices.

The material web31thereafter reaches the heating unit28of the forming station26, in which the material web31is heated to a temperature necessary for thermoforming. In practice, it has shown to be suitable to heat a material web made of PET to a relatively low thermoforming temperature, such as 100° C.

When the material web31is subsequently led up to the pressing unit29of the forming station26, a tool33comprising two tool halves engages with the heated material web31for thermoforming thereof. The tool33is thus configured such that, upon engagement with the material web31, it thermoforms hinge joints and locking members of the respective opening device. The tool33can also comprise cooling members for cooling the material web following completed thermoforming. Alternatively, cooling members, should such be required, can be arranged separately from the forming station26.

Finally, the material web31reaches the separating station27and in the embodiment shown a knife member34engages with the material web31for detachment of individual opening devices1.

It will be appreciated that the heating unit28and the pressing unit29can be integrally configured. It will also be appreciated that the separating station27can be integrated in the forming station26.

It will also be appreciated that the punching station can be dispensed with. The short sides of the opening device may be realized by preformed side edges of the material web. Alternatively, the separating station can be designed to cut all sides of the respective opening device.

Also, the separating station may be dispensed with. In this case, the web of interconnected opening devices may be rolled up in order to be supplied in roll-form to a filling machine.

The production line may be arranged to produce a web of interconnected opening devices comprising a plurality of opening devices in the transverse direction of the web. A roll comprising such a web of interconnected opening devices may be used in a filling machine arranged for filling packages in parallel fillings stations.

Further, the production line may also comprise an adhesive application station. The adhesive application station may be arranged to apply an adhesive layer partly or preferably entirely covering the application surface of each opening device. The adhesive layer may be in the form of a hot melt adhesive, also known as hot glue. The adhesive layer may be formed with an undulated or wave-formed surface.

The opening device can be applied to the package in connection with or following the production of the package.

It is also possible to apply the inventive opening device to the package before, during or after the filling thereof.

In particular, it is possible to apply an inventive opening device to a preformed package in the filling machine before the package has been filled.

The filling machine may comprise an applicator for application of said opening devices which as mentioned above may be supplied in said roll-form.

The applicator may comprise a knife or the like arranged to separate a single opening device from the web of interconnected opening devices. The knife may optionally be arranged to cut the contour of the opening devices to suitable shape.

The separating station can further comprise an indexable holder, which, following separation of an opening device, moves the separated opening device into a position in which the opening device can be applied in the opening portion of a filled package.

In case the opening devices comprise an adhesive layer in the form of a hot melt adhesive, the applicator may comprise a heater arranged to activate the adhesive layer. The heater may be a radiation-heater or a hot-air heater. If the surface of the adhesive layer is undulated or wave-shaped, the ridges of the surface will accumulate heat and ensure that the adhesive layer is still active in connection with application of the opening device on a package.

Alternatively, the heater may be in the form of a contact heater which is pressed against the adhesive layer. The contact ensures controlled heat transfer to the adhesive layer and may be provided with a surface treatment in order to prevent the adhesive layer from adhering to the contact heater. The contact heater may be provided with a surface profile in order to accomplish the undulated of wave-shaped surface of the adhesive layer.

The heater may affect the hinge joints of the opening device. For a w-shaped hinge joint, the bottom of the recesses and the top of the ridge may be rounded as a consequence of the heat exposure. The rounded bottom of the recesses may negatively affect the folding capability of the opening device. By forming the legs of the w-shaped cross section such, as previously described, that these are perpendicular to the contact surface, rounding of the recesses in connection with heat exposure may be avoided.

According to another aspect, the filling machine may comprise equipment which allows the production of opening devices, such as equipment which allows execution of the process described with reference toFIG. 8. The separating station can here be designed to cut all sides of the respective opening device in connection with the separation thereof. The separating station can further comprise an indexable holder, which, following separation of an opening device, moves the separated opening device by a rotary motion into a position in which the opening device can be applied in the opening portion of a filled package.

According to a further embodiment of the inventive opening device, which will be described below with reference toFIG. 10-15, the opening device1comprises a first body4, as described above with reference toFIG. 1-3, and a second body40.

The first body4and second body40of the opening device1are illustrated inFIG. 10. The second body40extends along a longitudinal axis41and has a second application surface for allowing the second body40on a package.

The second body40is further manoeuvrable between an unfolded position and a folded position by folding about a third folding axis42. InFIG. 11, the opening device1is illustrated with its first body4in its third position and its second body40in its folded position.

The third folding axis42of the second body40can extend, as in the embodiment shown, at right angles to the longitudinal axis41, but it will be appreciated that it is also possible to arrange the third folding axis42such that this extends at a non-right angle in relation to the said longitudinal axis41. In particular, the second folding axis3of the first body4can be angled in relation to the third folding axis42of the second body40such that the said folding axes are parallel in a state applied to a package.

A third hinge joint43having an extent which coincides with the said third folding axis42can be configured in the second body40. The third hinge joint43can have a v-shaped or w-shaped cross section.

The second body40further has a width B2which is less than half the width B1of the first body4. The second body40further has a length L2which is equal to or less than the length L1of the first body4.

It will be appreciated that the end portions of the first body4and the second body40can be configured other than is shown in the figures for adaptation to the geometry in the opening portion of the package on which the opening device1is intended to be disposed.

InFIG. 12a-12c, an opening portion16of a flexible package is illustrated, which opening portion16is formed by two opposing side walls17a,17bof the flexible package in a corner section of the same. An opening device1according to the said further embodiment is disposed in the said opening portion16.

The opening portion16of the flexible package comprises in the unopened state of the package an end tab18, which for initial opening of the package is separable from the package by detachment along a separation line19.

The first body4of the opening device1is disposed on a first17aof the said opposing side walls17a,17b, adjacent to the end tab18of the opening portion16, and, more precisely, is disposed on that side of the separation line19situated opposite the end tab18, adjacent to and parallel with this same separation line, as can be clearly seen fromFIG. 12a.

The second body4of the opening device1is disposed on a second17bof the said opposing side walls17a,17b, adjacent to the end tab18of the opening portion16, and, more precisely, is disposed on that side of the separation line19situated opposite the end tab18, adjacent to and parallel with this same separation line, as can be clearly seen fromFIG. 12b.

The separation line19can be configured as a initiation for facilitating detachment of the end tab18from the package. The initiation can comprise treated and untreated portions. The treated portions can be configured as weakenings, perforations or the like.

The opening device1can be applied in the opening portion15by the use of adhesive, such as a hot melt adhesive as described above, or by a heat-sealing process, or by some other suitable process.

As has been described above, the second body40has a length L2which is equal to or less than the length L1of the first body4and has a width B2which is less than half the width B1of the first body4. It hereby becomes possible to dispose the second body40within a region on the second side wall17b, which region, in the state of the opening device1applied to the package, is defined by the contour of one sub portion10aof the contact surface8of the first body4, as can be clearly seen fromFIG. 12c.

FromFIG. 12c, it can also be seen that the bodies4,40are mutually arranged such that the third folding axis42of the second body40is parallelly displaced in relation to the second folding axis3of the first body4. The folding axes3,42can be parallelly displaced with respect to each other with a distance apart A within the range 1-3 mm, but it will be appreciated that the parallel displacement can be greater or less than this. In certain applications, the parallel displacement can be wholly dispensed with.

For initial opening of the package, its end tab18is removed, and for further opening of the package into its opened-up state, the first body4is manoeuvred into its opening position and the second body40into its folded position, as is illustrated inFIGS. 13aand 13b. In practice, the first body4is manoeuvred into its opening position and the second body40into its folded position simultaneously, by a user, with a thumb and index finger grip, pressing opposing short sides of the opening device1one against the other such that folding takes place about the second folding axis3and about the third folding axis42respectively. By virtue of the fact that the bending axes3,42in the embodiment shown are parallelly displaced, it is ensured that the folding takes place in opposite directions. From the figures, it can be seen how the opening20in the opening portion16is opened up and acquires a well-defined pouring area having a contour which assumes the form of a parallelogram.

As can be seen from the figures, the first body4and the second body40are configured so that these do not extend beyond the connecting portion in which the side walls17a,17bof the package are mutually connected, but keep within the width of the opening portion. One of the said bodies4,40could be permitted to have an extent beyond the said connecting portions, but the fact that at least one body lacks such an extent ensures that the two bodies4,40do not counteract each other in connection with opening of the package into its opened-up state.

The said further embodiment of the inventive opening device1minimizes the incidence of drips after a completed pouring process. Surface tension effects namely imply that remaining product residues can be better detained between the side walls17a,17bin the bottom corners44of the opening20. The opening device produces, however, a lower opening angle α of the opening20, which lower opening angle α is large enough to overcome these surface tension effects. It is thus the second body40which, when the package is opened into its opened-up state, strives to angle the second side wall17baway from the first side wall17ato a sufficient degree to allow the attainment of a lower opening angle α which is sufficiently large.

Where an opening device without a second body is used on a package, it can happen that the second side wall along a short distance extends parallel with the first side wall so as subsequently to be angled off. When the first body is used together with a second body, as in the embodiment shown, it is ensured that the second side wall17bis angled off from the first side wall17aat a well-defined lower opening angle, which is advantageous for overcoming the surface tension effects which strive to detain product residues in the opening portion.

The lower opening angle α which is required to overcome the surface tension effects is dependent on the product which is housed in the package. For example, the lower opening angle α needs to be greater for milk than for water. The lower opening angle α can be within the range 15-65° or, more preferably, within the range 35-55°.

As has been described above, the opening device1does not need to be configured such that the opening position of the first body4and the folded position of the second body40are identical in each manoeuvring operation for opening up a package. This means that the lower opening angle α can be permitted to vary somewhat with repeated openings of the package into its opened-up state.

InFIG. 14, to which reference is now made, the pouring portion of the package is illustrated in the resealed state of the package. By virtue of the fact that the second body40is disposed within or inside a region defined by one sub portion10aof the contact surface8of the first body4, it is possible to manoeuvre the first body4into its second position by folding about the first folding axis2without the second body40preventing the said manoeuvring. The fact that the second body40is smaller than the said sub portion10aalso implies that the second body40can be placed at a distance from the first folding axis2, as can be seen from the figure. It is hereby ensured that the second body40does not act upon the side walls17when these are folded in connection with resealing of the package, which enables repeated, substantially liquid-tight resealing.

It will thus be appreciated that the present invention is not limited to the described embodiments.

For example, the above-described process for producing an opening device can be adapted such that the process also allows production of the second body of the opening device according to the above-described further embodiment.

In addition, it is conceivable to configure the inventive opening device integrally with the side walls in the opening portion of the package.

It is also conceivable to configure the package such that its geometry helps the opening device to be acted upon, when its locking members have not been activated, such that the package assumes its opened-up state. This can be realized, for example, in such a way that the opening portion is given a somewhat protruding geometry such that the package, under the influence of gravity, forms a fold which serves to separate the side walls in the opening portion. The fold will thus serve for manoeuvring of the first body into its opening position and, where appropriate, of the second body into its folded position, which corresponds to the opened-up state of the package.

Many variations and modifications of the present invention are thus possible. The scope of the invention is therefore defined solely by the appended patent claims.