EP2354022B1 - Can lid and method for manufacturing a can lid - Google Patents

Description

The invention relates to a can lid with a resealable opening, in particular for beverage cans, with a limited by a circumferential, provided in the metallic cover material Aufreißkerbe opening area, and a specific for breaking the Aufreißkerbe two-armed lever member, which is connected on the one hand with a pull tab and on the other hand to the opening area the lid surface acts and is supported by a force applied to the pull tab opening force translating bearing.

Furthermore, the invention is directed to a method of manufacturing a can lid as well as cans equipped with such a can lid.

US 2009/001081 A1 describes a resealable Dosendeclei with the features of the preamble of claim 1. In one embodiment, a sealing against the lid part to be pressed plastic seal is provided for sealing the once torn metal lid part when reclosing. US 6,286,703 B1 describes a can lid, in which an opening gap in the cover metal bridging plastic seal is torn open during initial opening and the seal parts are placed together again when reclosing.

From the EP 1 607 341 A1 For example, a can lid having a reclosable opening is known in which an opening is made in the metallic can lid and the edge of that opening is crimped to provide anchoring for a prefabricated plastic closure. The plastic closure part comprises a base part to be connected to the beaded edge of the can opening, in which opening formed by a flat plug is formed. The flat plug is connected to the opening edge via a plastic tear seam, so that the flat plug connected to a pull tab can be released by pulling over the tear tab of the plastic base part and pivoted into an open position. The opening can be preferably conical by pressing the on its underside trained Flachstopfens be temporarily closed again.

From the WO 2008/098558 A1 a can lid having a reclosable opening is known, in which an opening is also made in the metallic can lid into which a prefabricated, tearable plastic closure member is inserted, the prefabricated plastic member has a double flange at the edge into which engages the edge of the punched can opening and is fixed in it. The prefabricated plastic element comprises a closure part, which is connected to the peripheral edge of the plastic part via a tear seam. A pull tab connected to the closure part makes it possible to tear open the plastic tear seam between the peripheral area of the plastic part and the lid part and thus release the can opening. For the purpose of resealing, the closure part, which preferably remains in contact with the peripheral area via a tab region, can be pressed back into the opening.

From the GB 1 389 351 is a resealable can lid is known in which in particular the emergence of sharp edges should be avoided, as they arise when tearing ordinary tin cans over a tab. For this purpose, a prefabricated plastic part is snapped into a provided in the metallic can lid punched, which has a lid part which is connected via a thin plastic wall with the snapped into the can opening base part. About a pull tab, the thin connecting wall between the closure part and the base part destroyed and the can opening are exposed. The closure part is designed so that it engages to reclosure of the opening via a snap-locking connection in the base part.

From the DE 89 11 286 U is a beverage can with a Eindrückdeckelverschluss known in which the tear tab is rotatably mounted on the cover wall and provided on it a closure element which is taken during rotation of the pull tab from the tear position in a Verschließstellung above the open pouring and covering the pouring over covering or closing in this intervenes.

From the DE 90 05 150 U a beverage can with a lid consisting of sheet metal is known, in which a weakening line is formed and delimited by the weakening line lid part is detachable by means of a pull tab, wherein on the lid captive a substantially parallel to the lid surface pivotable closure part is attached to the removal opening.

From the DE 196 13 246 a metal lid for beverage cans is known, which has a pre-punched pouring opening in the lid surface, which is sealed by a closure element and after the first opening is again tightly closed. In this case, the lid and closure element can be positively connected to one another by means of bayonet-like interlocking elements, which are formed directly from the lid material or the closure element.

The known constructions for resealable can lids are disadvantageous in terms of the required ease of handling, the gas tightness essential to the durability of the particular can contents, and the usability in conventional can filling lines, which has led to these can closures not being used on an industrial scale.

The object of the invention is to provide a can lid, in particular for beverage cans, with a reclosable opening which not only processes a can filling line in the facilities available, i. applied to the can and can be connected to this air and gas-tight, but above all ensures a high-quality, gas-tight and liquid-tight seal in the reclosable opening, which withstand required pasteurization occurs high internal pressures, only low opening and Wiederverschlusskräfte requires and in particular also allows one-handed operation when opening and closing.

This object is achieved according to the invention, starting from a can lid with the features mentioned in the preamble of claim 1 in that the opening portion is formed as a closure lid and adjacent to its outer edge of the tear notch frictionally connected to a collar part of a first plastic material that the collar part a outside the opening area and the tear notch adjacent to the lid surface frictionally connected lid receiving part is assigned from a second plastic material, that the collar part engages over the lid receiving part and between the collar part and the lid receiving part a sealing snap-locking connection is formed with a circumferential dome rib and a complementary shaped recess and that the pull tab is fastened radially outside the lid receiving part to a fixing region of the collar part and the two-armed lever for breaking the tear notch of a Fixing region associated part-circumferential region of the collar part is formed.

By turning away from previously known, prefabricated closure units that had to be connected via flange elements and the like with the can lid, and the integration of lid receiving part and collar part according to the invention in the lid having a circumferential tearing notch a very compact, liquid-tight and gas-tight reclosable unit is created on the one hand which can be opened with little force by exploiting a partial circumferential region of the collar part as supported on the lid receiving part lever and easily meets the required requirements for tightness in the case of reclosing the can opening due to the provided positive snap-locking connection.

In order to ensure the captivity of the reclosure ensuring collar part, a pivot plate connection is preferably provided opposite the fixing region between the collar part and at least one provided on the cover surface anchoring element, wherein anchoring element, pivot plate connection and collar part made of the same plastic material.

According to one embodiment of the invention, it is provided that the pull tab consisting of a third plastic material rests on the collar part in the resting state and extends from the fixing region approximately to the opposite inner edge of the collar part, wherein the elasticity of the material of the pull tab is greater than the elasticity of the material the lid receiving part, which in turn is in turn more elastic than the material of the collar part when the lid receiving part of the snap-locking connection associated recess is provided. This embodiment promotes easy handling while minimizing the space required for the pull tab.

Since can ends are usually coated on both sides over the entire surface with a synthetic resin paint, which receives no or only inadequate connection with plastic materials, an embodiment of the invention is characterized in that the non-positive connection of the collar part with the metallic opening portion and the lid receiving part with the lid surface respectively over The circumference distributed openings or passages provided in the lid material and these breakthroughs or passages on both sides of the lid material edge-spanning with the respective plastic material are gas-tight encapsulated. It is particularly advantageous if the faces and the adjacent edge regions of the openings or passages are previously encapsulated with a fourth plastic material in the form of an elastic sealing material and this sealing material by the surrounding him and connecting with him plastic material of the collar part or the lid receiving part under bias is set.

In this way, a perfect, gas-tight seal is ensured also with respect to the paint layers, wherein the bias is achieved by the injection pressure and the resulting during spraying emphasis.

According to an alternative embodiment of the invention, it is provided that groove and / or teilnutförmige recesses, in particular with undercuts and / or welded metallic for positive connection of the collar member with the metallic opening portion and the lid receiving part and the anchoring element with the lid surface in the opening area and in the lid surface Retaining elements are provided, and that collar part, lid receiving part and / or anchoring element are positively and non-positively fixed in the recesses by an injection molding process.

In this embodiment, it is unnecessary to provide the can lid with openings, i. it is guaranteed from the outset, the required gas tightness.

Conveniently, in the preferably at least one film hinge comprehensive swivel flap connection between the collar part and the anchoring element a known buckling spring element integrated, which holds during pivoting of the cover part performing collar part over a Aufschwenkwinkel of advantageously more than 90 ° this cover part in the pivoted position. A pivoting back of the cover part is possible without problems in connection with such a buckling spring element.

In order to ensure the requirement for stackability of a can equipped with the can lid according to the invention as in the case of conventional doses, the height of the above the metallic lid surface located structure of lid receiving part, collar part and pull tab is designed so that it is less than the distance between the lid surface and bead , It is also possible to keep the can lid circumference free while maintaining a second can, which is parked on a can lid, and at the same time to ensure that the plastic components are spatially compact enough to fit into the inside arch usually formed in a can bottom.

For the practical handling of particular advantage is further that the pull tab for actuation is particularly easy to grasp or under attack, since between the pull tab and the opening area in the can wall always a defined, in particular by the collar part height given distance exists. This distance makes it possible to easily grasp the pull tab with a finger, slightly lift the pull tab and then apply the required for the purpose of full can opening traction. Any risk of injury or damage to a fingernail during the opening process is thus eliminated, and a one-hand or blind operation is possible without any problem.

Further advantageous features of a can lid according to the invention are specified in the subclaims and are also explained in the description.

The invention further relates to a method for producing a can lid with an outer bead and inwardly recessed lid surface in which a resealable opening is provided.

The inventive method, which is characterized by particular simplicity and the achievable quality of resealable opening unit, is in particular that the lid punched and introduced into the cover surface a circumferential tear notch and the tear notch at least on the outside adjacent an annular groove is formed in the lid surface, that Subsequently, while anchoring in the annular groove, a lid receiving part is injected with a first coupling element of a predetermined elasticity possessing plastic material, that then used the can lid with the lid receiving part as a counter-mold and an annular collar part injected from a not with the material of the lid receiving part plastic material and the tear notch is frictionally connected inwardly adjacent the lid surface, said annular cantilever being configured to receive the lid rushes over and a complementary to the first coupling element second coupling element and both coupling elements form a snap-locking connection, and that in particular simultaneously with the collar part a pull tab made of elastic material is injected, which is anchored at one end in a radially outer portion of the collar part and extends in the form of a ring tab to the can lid center region.

The individual injection molding operations required for the production of the can lid can be realized problem-free in conventional technology, wherein it is clearly advantageous that in the course of production the lid surface with the already molded lid receiving part can be used as a negative mold for the next injection process to form collar part and anchoring element, so that the optimal interaction and the required form-fit can be perfectly achieved in connection with the reclosability.

Further features of the method according to the invention are specified in the subclaims.

Fig. 1

eine perspektivische Schrägansicht einer Ausführungsform eines wiederverschließbaren Dosendeckels nach der Erfindung,

Fig. 2

eine Draufsicht des Dosendeckels nach Fig. 1,

Fig. 3

eine Schnittansicht entsprechend der Linie C-C von Fig. 2,

Fig. 4

eine deutlich vergrößerte Schnittansicht entsprechend dem kreisförmig gekennzeichneten Teilbereich von Fig. 3, und

Fig. 5 bis 9

jeweils vergrößerte Detailansichten von erfindungsgemäßen, flüssigkeits- und gasdicht ausgebildeten Verbindungen zwischen dem metallischen, insbesondere mit beiderseitigen Lackschichten versehenen Dosendeckel und in situ angespritzten Kunststoffelementen wie Deckelaufnahmeteil, Kragenteil und/oder Verankerungselement.

Finally, the invention is also directed to a complete can for packaging flowable or pourable products, which is characterized in that it is closed with a can lid with the characteristics of one or more of the can lid related claims. The invention will be explained in more detail by means of embodiments with reference to the drawing; in the drawing shows:

Fig. 1

3 is an oblique perspective view of an embodiment of a resealable can lid according to the invention,

Fig. 2

a top view of the can lid after Fig. 1 .

Fig. 3

a sectional view along the line CC of Fig. 2 .

Fig. 4

a significantly enlarged sectional view corresponding to the circular marked portion of Fig. 3 , and

Fig. 5 to 9

in each case enlarged detail views of inventive, liquid and gas-tight connections between the metallic, in particular provided with mutual lacquer layers can lid and in-situ molded plastic elements such as lid receiving part, collar part and / or anchoring element.

Fig. 1 shows a conventionally designed in its basic form can lid 1 made of metal, which carries a paint layer on both sides in a conventional manner and is connected via a flange 2, preferably with the interposition of a sealing material, liquid-tight and gas-tight with the respective associated can.

In this cover, off-center offset, a resealable opening integrated, as will be explained in detail.

In Fig. 1 to recognize a connected with a tear tab 15 collar part 5, which is firmly connected to the opening portion 11 of the can lid is and encloses this approximately annular. The connected to the collar part 5 opening portion 11 which can be swung by means of the tab 15 during the opening process is anchored to ensure the captivity of the swing-up part in the can lid, a buckling spring element 22 ensures that the lid is held in the open position, especially when more than an angle of 90 ° is pivoted.

The top view Fig. 2 again shows those related to Fig. 1 already mentioned components, wherein in Fig. 2 additionally an anchoring element 14 is indicated.

The Fig. 2 illustrates that the reclosable opening with all its associated components is arranged off-center, in such a way that despite the presence of the resealable opening, the stackability is unchanged as in conventional doses.

Prerequisite for this, apart from the positioning, is above all the compactness of the reclosable opening according to the invention. The supernatant of the components of the resealable opening over the can surface is according to the invention only about 2 mm.

Fig. 3 shows the basic structure of the integrated in the can lid resealable opening according to the invention in a sectional view along the line CC in Fig. 2 ,

One of the essential requirements of a resealable can lid is that the can sealed with a can lid must be liquid-tight and gastight, especially in the area of the resealable opening. It is to take into account that in the can production, the filled cans are heated to about 80 ° C for about 20 minutes, creating an internal pressure in the range of about 6 bar and this internal pressure must not cause it immediately or when the cans are delivered , comes to a gas leak.

Even after the can has been opened via the resealable closure, this closure must ensure that gastightness is ensured, since shaking or vibration effects can cause internal pressures in the range of approximately 2 bar, which could lead to undesired outgassing effects if the resealable gas can escape Closure would not ensure the required tightness.

Fig. 3 shows that the resealable closure according to the invention is not a prefabricated unit which is inserted into a corresponding opening of the can lid, but a structure in which closure components are integrated in the metallic can lid and the tear-open area by a conventional tear notch in the metallic can lid is defined. The essential components of the closure according to the invention are formed by a circumferential cover receiving part 10 and a cooperating with this snap-lock type collar part 5, which forms the hinged lid part together with the opening portion located within a tear notch, which via a pivot plate connection 16 with an anchoring element 14th connected is. On the collar part engages on the outside and the anchoring element 14 opposite the pull tab 15 at.

Fig. 4 shows the specific structure of a preferred embodiment of a can lid according to the invention with a reclosable opening.

In the respect to the edge-side visible surface 23 slightly recessed lid surface 3, an opening portion 11 is defined by a circumferential tear-4 of known type. Adjacent to the tear notch 4 and outside the opening portion 11 a circumferential annular groove 17 is introduced into the lid surface 3. This annular groove 17 desirably increases the rigidity, but it also has an advantageous effect if an increased pressure, in particular the pressure of about 6 bar arising in the pasteurization step, occurs in the can, since this annular groove provides a certain length or area compensation, when the can inflates a bit. This length or area compensation also protects the adjacent tear score.

In the bottom of the annular groove 17, a perforation is provided, which may consist of mutually spaced round, oval or elongated holes. Instead of such perforations or mixed with such perforations, so-called passages may also be provided, i. Openings with downwardly extending, short wall approaches.

The perforations or passages make it possible for the area of the annular groove 17 to be enclosed on all sides by the plastic material used for the lid receiving part 10 when the lid receiving part 10 is sprayed. Since, due to the coating of the lid material with a lacquer can not be readily ensured that a perfect gas-tight connection between the can lid material and the plastic material is achieved, there is a special feature of the invention in that before spraying the lid receiving part, the free end faces and the surrounding areas of the openings 7 or passages are encapsulated with an elastic sealing material. During subsequent spraying of the lid receiving part 10, on the one hand a connection between the elastic sealing material 8 and the plastic material of the lid receiving part 10 is achieved, but of crucial importance is that the sealing material 8 is biased by the plastic material of the lid receiving part 10, so that even then the interior of the can is sealed completely gas-tight with respect to the atmosphere, if the plastic materials do not combine with the lacquer used for the can lid coating, because a seal working with permanent mechanical prestressing is realized here.

When spraying the lid receiving part 10 an annular recess 12 is provided which has approximately the shape of a downwardly widening U in cross section and is suitable to form a snap-locking receptacle with a corresponding counter-element.

The circumferentially provided adjacent to the tear notch 4 cover receiving part 10 is associated with a collar part 5, which consists of a different from the lid receiving part 10 plastic material and is chosen so that it does not connect with the injection molding process with the material of the lid receiving part 10.

The collar part 5 is fixedly and gastightly connected to the opening part 11 of the can lid, to which adjacent to the tear notch 4 in the region of the outer periphery of the opening portion 11 openings or passages approximately analogous to the openings or passages at the bottom of the annular groove 17 are provided. These breakthroughs 7 or passages - the can not be seen in the right part of the representation of the collar part 5 due to the cutting process - are in turn encapsulated in the region of their faces and the adjacent areas with an elastic sealing material 8, so that in the formation of the collar part the corresponding plastic material pass through the openings 7 or passages and below the opening portion 11 may form a fastening lug. The plastic material of the collar part 5 and the elastic sealing material 8 also act together again in the same way, as has already been described in connection with the lid receiving part 10, that is, there is a mechanically strong, gas-tight connection between the material of the opening portion 11 and Collar part 5 created.

During the formation of the collar part extending beyond the lid receiving part 10, a rib 9 which is shaped complementarily to the recess 12 in the lid receiving part 10 is formed, so that the snap snap connection already mentioned can be created.

Simultaneously with the shaping of the collar part 5, in which the can lid surface and the lid receiving part already integrated therein serve as a counter-mold, a swivel-plate connection 16 with a likewise simultaneously formed anchoring element 14 in the lid surface 3 is created. The anchoring element 14 is formed in the same way and is constructed in the same way as the connection between the collar part 5 and the opening portion 11, ie it is also ensured due to the provided between can lid opening 7 and the plastic material of the anchoring element elastic sealing gas tightness. Between film hinges 21, which are provided adjacent to the anchoring element 14, in the pivot plate connection 16 is an existing of the same material Buckling spring element 22 integrated by conventional design. This buckling spring element 22 holds the cover in the open position when it is swung open by more than 90 °. When closing the lid, the buckling spring element 22 snaps over and obstructs the closing process in any way.

At the region of the collar part which is located closest to the beading edge 2 and which is opposite the anchoring element 14, the collar part 5 is connected to the fixing strap 13 with the flexibly formed pull tab 15, wherein the connection preferably takes place in the context of an injection process. The pull tab 15 extends to the opposite inner region of the collar member 5, is applied to this and parallel to the plane of the opening portion 11, i. it is in the closed state of the resealable opening before a very space-saving, compact arrangement, the height is significantly less than the distance between the top surface 3 and the bead 2.

It has already been mentioned that different plastic materials are to be used for different components. In the embodiment according to Fig. 4 a plastic material is used for the lid receiving part, which is a slightly widening of the recess 12 when pressing the dome rib 9 and then holding this dome rib 9 via a rounded undercut and on the other hand the exercise of a necessary bias on the plastic material used for the elastic sealing material 8 after the Spraying guaranteed. The plastic material for the elastic sealing material 8 is much more elastic than the plastic material of the lid receiving part. For the collar part 5, a plastic material is used, on the one hand with the material of the lid receiving part 10 no connection and on the other hand is also much less elastic than This is also important because the collar part 5 must have a basic rigidity, which is required for the can opening operation.

The plastic material used for the pull tab preferably again differs from the three already mentioned plastic materials and is so elastic that the pull tab can be easily raised by grasping and then operated in the manner required to open.

To open a can for the first time, it is necessary for the circumferential tear-open notch 4 to be broken and then the lid part formed by the opening region 11 and the collar part 5 to be swung up on one side.

Since a relatively small opening force is required with respect to the opening operation, an opening force ratio is provided in the subject of the application, which is realized in that the pull tab 15 is hinged to the radially outer fixing portion 13 of the collar member and by pulling the radially outer end of the collar member 5 by means of the pull tab Supporting the collar part on the radially inner leg of the recess 12 of the lid receiving part 10 takes place and thus the relatively long lever between this leg and the fixing portion 13 cooperates with the much shorter lever acting between this acting as a support leg radially inner leg of the lid receiving part and the attachment point of the Collar portion 5 is formed on the opening portion 11 and is effective. The shorter lever is thereby moved inwards, ie toward the interior of the can and the resulting deformation causes - supported by the provision for increasing the rigidity local projection 25 - a local breaking of the tear-4, the is then separated on further pulling up the pull tab 15 with little force over the entire circumference. In this case, the dome rib 9 leaves the corresponding recess 12 in the lid receiving part. The lid can then be removed after complete separation of the snap-locking connection on the pivot plate connection 16 and the film hinges 21 of the formed free opening and swung up. By the existing buckling spring element 22 of the open lid is held in the open position.

To reclosure of the opening of a precisely guided by a two-armed pivot plate connection 16 cover part is brought back to rest on the cover receiving part 10, wherein the form-fitting in the corresponding recess 12 snapping circumferential rib 9 by slight pressure in the in Fig. 4 shown closed position can be transferred.

The initial opening of a can differs from subsequent opening and closing operations as a rule by the fact that the force required for the first opening is several times as large as the force required for reopening after reclosure and, above all, the noise perceptible in each case is significantly different is.

If desired, between the lid receiving part 10 and the collar part 5 at least one by the initial opening operation of the collar member 5 inevitably in its structure and / or its appearance and / or its position changed visual element can be provided.

Below are still various alternatives of the connection of collar part and / or lid receiving part explained with the metallic can lid surface.

Fig. 5 shows the already explained variant, in which between the metallic, provided with a top coat sheet 17 and the plastic material of the lid receiving part 10 or collar part 5, a sealing material in the region of the opening 7 is provided.

Fig. 6 shows a variant in which breakthroughs or passages in the can lid material can be avoided. For this purpose, recesses 18 are formed in the material of the can lid, which are provided with at least one undercut 19. If the plastic material for the lid receiving part or the collar part is injected into such a recess, then there are force and form-fitting connections that ensure the required secure hold of the plastic material.

Fig. 7 shows a further embodiment, in which instead of in Fig. 6 provided undercut in the annular groove 17 specially shaped retaining elements 20 attached, z. B. are welded, which allow the same effect avoiding undercuts.

Fig. 8 shows a variant in which between the metallic sheet of the annular groove 17 and the plastic material used for the lid receiving part 10 or the collar part 5, a bonding agent 24 is provided which, even if the metal sheet is provided with a paint layer, a mechanically stable and especially ensures a gas-tight connection between plastic and metal. The layer of bonding agent 24 is provided inside the can on the metal sheet.

Fig. 9 shows an embodiment in which in turn in the lid surface of the can lid no perforations are required, but the gas-tight fixing of collar part 5 and / or lid receiving part 10 takes place in a recess which is provided with a primer layer 24 having a gas-tight connection between plastic and metal ensures.

The inventive method for producing a can lid with a resealable opening comprises in particular the following method steps:

When punching the metallic lid, an annular groove is formed in the lid surface on the outside adjacent to the intended circumferential tear-open notch. According to a variant of the invention, such an annular groove can also be provided on the inside of the tear-open groove. After the formation of the annular groove or annular grooves, the opening region delimiting, circumferential tear-open notch is introduced into the lid surface. In the case of providing annular grooves located on both sides of the tear notch, these serve later for fixing the collar and lid holding parts to be formed. Preferably, an annular groove is provided only outside the tearing notch, in which a lid receiving part is fixed in a manner to be described.

According to an advantageous variant, in particular in Fig. 4 is shown and provided in the outside of the tear notches perforations without annular groove and within the tear notch perforations in an annular groove are introduced simultaneously or offset in time to form the outer annular groove in the bottom of the annular groove and in the tear-open inside adjacent area perforations.

In a next process step, the perforations are encapsulated on the face side and in the vicinity of their end faces with an elastic sealing material.

In a further method step, the lid receiving part is injection-molded with the use of the corresponding mold parts while enclosing the elastic sealing material already present on all sides, preferably simultaneously with a support area for a pivoting lug located on the side of the anchoring element.

The resulting structure of metallic lid surface with integrated lid receiving part is used for the next injection molding process as a counter-mold, so that the annular recess in the lid receiving part forms the counter-form region for the positively engaging dome rib, which is an integral part of the annular collar part. When spraying this annular collar part penetrates the plastic material through the already provided with an elastic sealing material breakthroughs, wherein on the elastic sealing material by the injection pressure and the resulting during spraying forcing a permanent bias is applied. The plastic materials used for the collar part and the lid receiving part enter into a connection with the elastic sealing material. Simultaneously with the spraying of the collar part, the anchoring element and the pivot plate connection, in particular with buckling spring element, are preferably sprayed.

At the same time or offset in time for spraying the collar part, the pull tab is injected using an inclined shape, wherein in the fixing region between pull tab and anchoring element the pull tab material in correspondingly provided recesses of the Collar material can penetrate and in this way the pull tab is fixed.

The manufacturing process, in which four different plastic materials are used in the above-described case, depending on the in the Fig. 5 to 9 shown connection possibilities between the lid material and collar part or lid receiving part can be modified. For example, in the case of variants according to the 6, 7 and 9 the formation of perforations in the lid material omitted, as well as the application of these perforations associated sealing material. For this, process steps for applying a bonding agent or for attaching retaining elements are required.

However, all embodiments of the invention have in common that the resealable can lid in the conventional production process, i. the process of processing can lids without resealable opening, processable and thus applied with the available facilities a can filling line on the respective can and the can can be closed. The gas-tightness achieved according to the invention also ensures that the durability of the particular contents of the can is in no way adversely affected in comparison with non-re-closable cans.

Finally, it should also be mentioned that in the can lid according to the invention favored by the space under the pull tab opening the can by a one-handed operation is possible without problems, since the easily accessible pull tab gripped with a finger and pulled in the direction of anchoring point under opening of the can can. The realized power transmission has a particularly advantageous effect.

LIST OF REFERENCE NUMBERS

1

can end

2

beaded

3

Cover surface (opening area)

4

tear notch

5

Collar part (first plastic material)

6

mounting boss

7

Breakthrough, passage

8th

elastic sealing material (fourth plastic material)

9

dome rib

10

Lid receiving part (second plastic material)

11

opening area

12

recess

13

fusing

14

anchoring element

15

Pull tab (third plastic material)

16

Pivoting splice

17

ring groove

18

wells

19

undercut

20

Retaining element

21

film hinge

22

Buckling spring element

23

viewing area

24

bonding agent

25

projection

Claims (23)

1. A can lid having a sealinly reclosable opening,
   in particular for beverage cans,
   having an opening region (11) bounded by a peripheral tear notch (4) provided in the metallic lid material of a lid surface (3);
   as well as having a two-armed lever member intended for breaking through the tear notch (4);
   which is connected to a pull tab (15), on the one hand, and engages at the opening region (11) of the lid surface (3), on the other hand, and is supported via a support stepping up the opening force applied to the pull tab (15);
   characterized in that
   the opening region (11) is formed as a closure lid and is connected at its outer margin adjacent to the tear notch (4) in a force-transmitting manner to a collar part (5) composed of a first plastic material;
   in that a lid receiving part (10) composed of a second plastic material and connected in a force-transmitting manner outside the opening region (11) and adjacent to the tear notch (4) to the lid surface (3) is associated with the collar part (5);
   in that the collar part (5) engages over the lid receiving part (10) and a sealing snap-in latching connection having a peripheral coupling rib (9) and a cut-out (12) shaped in complementary form thereto is formed between the collar part (5) and the lid receiving part (10); and
   in that the pull tab (15) is fastened radially outside the lid receiving part (10) to a fixing region (13) of the collar part (5) and the two-armed lever is formed for breaking through the tear notch (4) by a peripheral part region of the collar part (5) associated with the fixing region (13).
2. A can lid in accordance with claim 1,
   characterized in that
   a pivot tab connection (16) is provided opposite the fixing region (13) between the collar part (5) and at least one anchorage element (14) provided at the lid surface (3), with the anchorage element (14), the pivot tab connection (16) and the collar part (5) comprising the same plastic material.
3. A can lid in accordance with claim 1,
   characterized in that
   the pull tab (15) comprising a third plastic material lies on the collar part (5) in the state of rest and extends from the fixing region (13) approximately up to the oppositely disposed inner margin of the collar part (5),
   with the elasticity of the material of the pull tab (15) being larger than the elasticity of the material of the lid receiving part (10) which is in turn more elastic than the material of the collar part (5).
4. A can lid in accordance with claim 1 or claim 2 or claim 3, characterized in that
   holes (7) or passages are provided in the lid material respectively distributed over the periphery for the force-transmitting connection of the collar part (5) to the metallic opening region (11) and of the lid receiving part (10) to the lid surface (3) and these holes (7) or passages are overmolded by the respective plastic material in a manner engaging over the margin in a gas-tight manner at both sides of the lid material (3, 11).
5. A can lid in accordance with claim 4,
   characterized in that
   the end surfaces and the adjacent marginal regions of the holes (7) or passages are overmolded by a fourth plastic material in the form of an elastic sealing material (8); and in that this sealing material (8) is set under a preload by the plastic material of the collar part (5) or of the lid receiving part (10) surrounding said sealing material and connecting to it.
6. A can lid in accordance with claim 4 or claim 5,
   characterized in that
   the holes (7) or passages are provided for connecting the lid receiving part (10) and the lid surface (3) at the base of a substantially U-shaped ring groove (17) extending to the inner can space.
7. A can lid in accordance with claim 1 or claim 2 or claim 3,
   characterized in that
   groove-like and/or partial groove-like recesses (18), in particular with undercuts (19) and/or with welded metallic retaining elements (20), are provided in the opening region (11) and in the lid surface (13) for the force-transmitting connection of the collar part (5) to the metallic opening region (11) and of the lid receiving part (10) and also of the anchorage element (14) to the lid surface (3); and in that the collar part (5), the lid receiving part (10) and/or the anchorage element (14) are fixed in shape-matched and force-transmitting manner in the recesses (18) by an injection molding process.
8. A can lid in accordance with claim 2,
   characterized in that
   the pivot tab connection (16) includes a two-limbed film hinge (21) and a kink spring element (22) which is formed between the limbs and which holds the pivoted open closure lid (5, 11) in an obtuse-angle open position.
9. A can lid in accordance with claim 1,
   characterized in that
   the peripheral coupling rib (9) is provided at the collar part (5) and the cut-out (12) of complementary shape is provided in the lid receiving part (10).
10. A can lid in accordance with any one of the preceding claims,
    characterized in that
    the pull tab (15), in particular designed in ring form, is held by the collar part (5) spaced part with respect to the metallic opening region (11) and the pull tab (15) can be gripped by being engaged beneath and actuated by an opening finger due to its spacing.
11. A can lid in accordance with one or more of the preceding claims,
    characterized in that
    at least one visible element is provided between the lid receiving part (10) and the collar part (5) whose structure and/or whose appearance and/or whose position is necessarily changed by the first-time opening procedure of the collar part (5).
12. A can lid in accordance with one or more of the preceding claims,
    characterized in that
    the height of the structure of lid receiving part (10), collar part (5) and pull tab (15) disposed above the metallic lid surface (3) is smaller than the spacing between the lid surface (3) and the beaded over rim (2).
13. A can lid in accordance with one or more of the preceding claims,
    characterized in that
    the lid surface (11, 3) associated with the mounting region of the components (5, 10, 14) comprising plastic material is recessed with respect to the visible surface (23) surrounding it at all sides.
14. A method of manufacturing a can lid (1) having an outer beaded over rim (2) and having a lid surface (3) which is set back inwardly thereto and in which a reclosable opening is provided,
    characterized in that
    the lid (1) is punched and a peripheral tear notch (4) is introduced into the lid surface (3) and a ring groove (17) is formed in the lid surface adjacent at least to the outside of the tear notch;
    in that subsequently a lid receiving part (10) having a first coupling element comprising a plastic material having a predefinable elasticity is injection molded with a simultaneous anchorage in the ring groove;
    in that the can lid (1) having the lid receiving part (10) is then used as a counter mold and an annular collar part (5) comprising a plastic material not connecting to the material of the lid receiving part is injected and is connected to the lid surface (3) in a force-transmitting manner adjacent to the inner side of the tear notch (4), with this ring-shaped collar part (5) being designed so that it engages over the lid receiving part and has a second coupling element shaped in a complementary manner to the first coupling element and both coupling elements form a snap-in latching connection; and
    in that a pull tab (15) comprising elastic material is injected, in particular simultaneously with the collar part, is anchored at one end in a radially outwardly disposed part region of the collar part (5) and extends in the form of a ring tab to the center region of the can lid.
15. A method in accordance with claim 14,
    characterized in that
    a coupling cut-out (12) aligned substantially perpendicular to the lid surface and designed approximately in U shape in cross-section is formed as the first coupling element and a coupling rib (9) of complementary shape is formed as the second coupling element.
16. A method in accordance with claim 14,
    characterized in that,
    simultaneously with the formation of a peripheral groove in the lid surface (3), holes or passages (7) are punched, distributed over the periphery, in the base wall of the peripheral groove and in the region adjacent to the tear notch (4) for fastening the collar part (5), said holes or passages being interspersed in the injection process by the respective associated plastic materials for the lid receiving part (10) and the collar part (5) so that the regions adjacent to the holes or passages (7) are embedded in the respective plastic material at both sides of the lid surface (3).
17. A method in accordance with claim 16,
    characterized in that
    an elastic sealing material is injected about the end faces of the holes or passages (7) as well as their adjacent marginal regions before the injection of the collar part (5) and before the injection of the lid receiving part (10), with this sealing material being connected to these materials and being set under preload on the injection of the materials for the collar part and the lid receiving part.
18. A method in accordance with claim 16,
    characterized in that
    simultaneously with the formation of the peripheral groove disposed outside the tear notch (4) in the lid surface (3), a peripheral groove is also formed adjacent to the tear notch (4) at the inner side in the material of the lid surface (3) and both peripheral grooves are provided with undercuts and/or retaining elements; and
    in that the materials for the collar part (5) and the lid receiving part (10) are anchored in these grooves in the subsequent injection processes free of material holes in a shape-matching and force-transmitting manner.
19. A method in accordance with any one of the claims 14 to 18,
    characterized in that,
    simultaneously with the injection of the lid receiving part, an anchorage element (14) disposed diagonally opposite the fixing region for the pull tab and spaced apart from the lid receiving part (10) is injected which is connected to the lid receiving part (10) via a pivot tab (16) in the same injection process and is composed of the same material.
20. A method in accordance with claim 19,
    characterized in that
    the mechanical connection between the anchorage element (14) and the lid surface (3) is established in the same manner as the connection between the lid receiving part (10) and the lid surface (3) and with the same injection processes.
21. A method in accordance with claim 20,
    characterized in that,
    on the injection of the pivot tab (16), simultaneously a two-limbed film hinge having a kink spring element (22) formed between the two limbs of this hinge is formed between the anchorage element (14) and the lid receiving part (10).
22. A can for packaging flowable or pourable products, in particular for the packaging of beverages,
    characterized in that
    the can is closed by a can lid (1) in accordance with one or more of the claims 1 to 10.
23. A can in accordance with claim 22,
    characterized in that,
    to ensure the stackability of the cans, the can base is inwardly arched in the manner of a dome and is formed for receiving the structure of lid receiving part (10), collar part (5) and pull tab (15) disposed above the metallic lid surface; and in that the can lid has a peripheral rim region free of structures.

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