Can lid

Abstract

The invention relates to a can lid (11) comprising: a metal lid surface (13) in which an opening region is formed; a sealing frame (21); a closure unit (25) which is pivotally attached to the metal lid surface via a first pivot bearing (27) and is designed to close the opening region directly or by means of a closure piece (19) of the metal lid surface carried by the closure unit, wherein the sealing frame (21) and the closure unit (25) sealingly cooperate via at least one sealing rib (51) and an associated receiving groove (53); and an annular pull tab (29) which is connected to the closure unit (25) via a second pivot bearing (35), wherein the annular pull tab, in a home position, is pivoted towards the closure unit and projects obliquely or transversely from the closure unit in a pull position. In the home position, the annular pull tab (29) radially engages around the closure unit (25) and exerts a radially inwardly directed clamping effect onto the closure unit, so that the sealing rib (51) is pressed against a wall of the receiving groove (53).

Description

[0001] Can lid

[0002] The invention relates to a can lid with a resealable opening, in particular for beverage cans, comprising a metallic lid surface in which an opening region is formed, a sealing frame made of plastic material which is connected to the metallic lid surface and encloses the opening region, a closing unit made of plastic material which is pivotally attached to the metallic lid surface via a first pivot bearing and is designed to close the opening region directly or by means of a closure piece of the metallic lid surface carried by the closing unit, wherein the sealing frame and the closing unit cooperate in a sealing manner via at least one sealing rib and an associated receiving groove, and an annular pull handle which is connected to the closing unit via a second pivot bearing opposite the first pivot bearing,wherein the ring-shaped pull handle is pivoted towards the closing unit in a basic position and protrudes obliquely or transversely from the closing unit in a pulling position.

[0003] Can ends of this type are used extensively in the production of beverage cans, food cans, and the like. Due to the interaction of the sealing rib and the receiving groove, a corresponding can end can be reclosed after opening. Before the can end is opened for the first time, the closure piece can be separated from the surrounding lid surface by a micro-gap or a weakening line extending at least partially along the edge of the lid surface, whereby a sealing film made of a plastic material applied to the inside of the can end can cover the micro-gap or the weakening line. After the can end is opened for the first time, the tightness of the reclosed can end can be ensured exclusively by the sealing rib and the receiving groove.

[0004] However, in certain situations, such as violent movement of the can, fluid may leak through the contact area between the sealing rib and the receiving groove when resealed. This is undesirable, even if the leakage is minimal.

[0005] It is an object of the invention to increase the tightness of resealable can lids of the type mentioned, in particular in the resealable state.

[0006] The problem is solved by a can lid having the features of claim 1.

[0007] According to the invention, the annular pull handle in the basic position radially encompasses the closing unit and thereby exerts a radially inwardly directed clamping effect on the closing unit, so that the sealing rib is pressed against a wall of the receiving groove.

[0008] The clamping effect results in tighter contact between the sealing rib and the receiving groove, thus providing a better seal between the interacting plastic components of the resealable closure, namely the sealing frame and the closing unit. The ring shape of the pull handle ensures that the clamping effect is effective all around, i.e., along the entire length of the sealing rib. Thus, the design according to the invention achieves a particularly reliable seal. Because the pull handle, which is already provided, is used to generate the clamping effect, there is no need for the costly provision of a separate clamping component. Due to the dual function of the pull handle, the manufacturing costs of a can end according to the invention are comparatively low despite the increased tightness.

[0009] The clamping effect can be achieved in a relatively simple manner by selecting the inner diameter of the ring-shaped pull handle slightly smaller than the outer diameter of the closing unit.

[0010] The term “radial” in the present disclosure is to be understood as “radial with respect to a ring axis of the ring-shaped pull handle”.

[0011] According to one embodiment of the invention, the sealing frame and the closing unit are designed such that when the annular pull handle moves from the basic position towards the pull position, air can pass through the arrangement of sealing rib and receiving groove due to the decreasing tensioning effect. This ensures pre-ventilation of the can before it is fully opened, which is also referred to as "venting". Venting prevents unwanted splashing or foaming as well as unpleasant noises. While venting during initial opening can be made possible, for example, by certain design features of the metallic lid surface, venting when opening from the reclosed state is not provided for in conventional resealable can ends.However, the pull handle that encompasses the closing unit and stretches inwards is capable of providing “reclosure venting” if it is sufficiently flexible.

[0012] Preferably, the annular pull handle is arranged at least substantially completely radially outside the closing unit in the home position, so that it can exert the most pronounced clamping effect possible. The annular pull handle and the closing unit can extend in a common base plane when the annular pull handle is in the home position. The space required by the closure components is thus minimal in the home position of the pull handle.

[0013] Preferably, a locking device with at least one retaining rib and a complementarily shaped recess is formed between an inner circumferential region of the annular pull handle and the closing unit. This reliably holds the pull handle to the closing unit. In particular, the locking device prevents inadvertent movement of the pull handle from the home position to the pull position and thus an inadvertent release of the clamping effect.

[0014] It is preferred that the retaining rib and the recess extend along the entire inner peripheral region of the annular pull handle in order to ensure a particularly secure hold.

[0015] According to one embodiment of the invention, at least one handling projection is arranged on an outer circumferential region of the annular pull handle. The handling projection facilitates lifting the pull handle from the basic position pivoted toward the closing unit, even if, in the basic position, it is flush with the closing unit and / or rests against the metallic lid surface. The handling projection can be easily grasped or gripped under with a finger or fingernail. Preferably, the handling projection is plate-like or knob-like. As soon as the pull handle protrudes diagonally or transversely from the closing unit, it can be grasped directly with two fingers for the opening process.A further embodiment of the invention provides that the sealing frame and the closure unit further cooperate in a sealing manner via a further sealing rib, which is located radially further inward than the other sealing rib, and an associated further receiving groove, which is located radially further inward than the other receiving groove. Upon opening the can lid, the further sealing rib and the further receiving groove continue to cooperate in a sealing manner even if the other sealing rib and the other receiving groove have already begun to detach. This improves venting. In particular, the radially inward sealing rib is capable of retaining foam entrained by the airflow.

[0016] The ring-shaped pull handle is preferably made of plastic. The type of plastic material can be selected depending on the desired flexibility.

[0017] In particular, the sealing frame, the closing unit, and the ring-shaped pull handle can be made of the same plastic material. This enables particularly simple and cost-effective production, for example, using an injection molding process.

[0018] According to a special embodiment of the invention, the sealing frame, the closing unit, and the annular pull handle are formed from a single plastic part. This allows for particularly simple production.

[0019] The first pivot bearing and the second pivot bearing can be formed by flexible connecting sections between the sealing frame and the closing unit on the one hand and the closing unit and the annular pull handle on the other hand, which enables a particularly simple construction.

[0020] Further developments of the invention can also be found in the dependent claims, the following description, and the accompanying drawings. The invention is described below by way of example with reference to the drawings.

[0021] Fig. 1 is a partial perspective view of a can end according to the invention.

[0022] Fig. 2 shows a resealable opening system of the can lid according to Fig. 1 with a pull handle in a basic position in a plan view.

[0023] Fig. 3 shows the opening system according to Fig. 2 in a side sectional view along the line AA in Fig. 2.

[0024] Fig. 4 is the enlarged section B of Fig. 3.

[0025] Fig. 5 is a perspective view of a plastic part through which a

[0026] Sealing frame, a closing unit and an annular pull handle of a can lid according to the invention are formed.

[0027] 1 and 2 show a can end 11, particularly intended for a beverage can, in whose metallic end surface 13 a resealable opening system 15 is integrated. The can end 11 can be connected to an associated container (not shown) via a flanged edge 17. An opening is provided in the metallic end surface 13, which opening, in the as-delivered state of the can end 11 shown in Fig. 1, is closed by a section of the metallic end surface 13 in the form of a closure piece 19. The closure piece 19 is separated from the surrounding end surface 13 by a micro-gap or a weakening line (not shown). The metallic end surface 13 is preferably formed from a sheet layer of aluminum or tinplate. A sealing plastic film can be applied to the inside of the can end 11, although this is not shown in the figures.

[0028] The resealable opening system 15 comprises a sealing frame 21 made of plastic material that surrounds the opening and is firmly connected to the surrounding lid surface 13. Furthermore, a closing unit 25 made of plastic material is provided, which supports the closure piece 19 and is attached to the surrounding lid surface 13 via a first pivot bearing 27.

[0029] A tear-open element in the form of an annular pull handle 29 (Figs. 2 and 3) is connected to the closing unit 25 and accordingly fastened to the closure piece 19. By pulling the pull handle 29, a user can pivot the closure piece 19 upward out of the opening plane 33 defined by the opening and thus release the opening, possibly tearing the sealing film. The connection between the pull handle 29 and the closing unit 25 is provided by a second pivot bearing 35, which is diametrically opposite the first pivot bearing 27. For a better overview, the pull handle 29 has been omitted in Fig. 1.

[0030] 2 and 3 show the annular pull handle 29 in a basic position. In this position, the pull handle 29 is pivoted towards the closing unit 25 and engages around it in the radial direction. To save installation space, the pull handle 29 is arranged completely radially outside the closing unit 25 in the basic position. The pull handle 29 also has the same height as the closing unit 25, so that the annular pull handle 29 and the closing unit 25 extend in a common base plane 39 when the pull handle 29 is pivoted towards the closing unit 25 as shown in a space-saving manner. Since the pull handle 29 is not easy for a user to grasp in this position, two plate-like handling projections 40 are provided at positions spaced from the second pivot bearing 35 on the outer peripheral region 41 of the pull handle 29.The handling projections 40 can be gripped with a finger or fingernail to lever the pull handle 29.

[0031] As can be seen in Fig. 4, a circumferential holding rib 45 with a rounded cross-section is located on the outer circumferential region 43 of the closing unit 25. This retaining rib engages in a complementarily shaped, likewise circumferential recess 47 on the inner circumferential region 49 of the pull handle 29 when the latter is in the home position. As a result, the pull handle 29 is held in a fixed position on the closing unit 25 and can only be pivoted into a pull position (not shown) with manual force, in which it protrudes obliquely from the closing unit 25 and can thus be easily grasped. To facilitate pivoting the pull handle 29 back from the pull position to the home position, a bevel 50 is provided on the upper edge of the closing unit 25.

[0032] As can also be seen from the enlarged detailed view of Fig. 4, a radially outer sealing rib 51 and a radially inner sealing rib 52 are formed on the sealing frame 21. Furthermore, a radially outer receiving groove 53 and a radially inner receiving groove 54 are formed on the closing unit 25. The interlocking sealing ribs 51, 52 and receiving grooves 53, 54 enable a detachable, fluid-tight connection between the sealing frame 21 and the closing unit 25. Accordingly, the can end 11 is resealable. It is understood that the sealing ribs 51, 52 could also be arranged on the closing unit 25 and the receiving grooves 53, 54 could also be arranged on the sealing frame 21. Depending on the application specifications, more than two pairs of sealing ribs 51, 52 and receiving grooves 53, 54 could also be provided.

[0033] The inner diameter of the pull handle 29 is adapted to the outer diameter of the closing unit 25, but is selected to be somewhat smaller in magnitude. Therefore, in the basic position, the pull handle 29 exerts an inwardly directed clamping effect on the closing unit 25, thereby pressing the sealing rib 51 against a wall of the receiving groove 53. The clamping effect acts along the entire circumference of the closing unit 25 in the direction of the ring axis 60 (Fig. 2). This achieves a high degree of tightness of the resealable opening system 15.

[0034] When a user lifts the pull ring 29 over one or both of the handling projections 40, the tension is released, resulting in deformation and, as a result, venting of the associated can. The sealing ribs 51, 52, which still engage to a certain extent in the receiving grooves 53, 54, prevent the escape of liquid or foam. Therefore, with the resealable opening system 15, venting is possible even after the initial opening.

[0035] Fig. 5 shows a one-piece plastic part 55 comprising the sealing frame 21, the closing unit 25, and the annular pull handle 29. The first pivot bearing 27 is formed by a flexible connecting section 57 between the sealing frame 21 and the closing unit 25, while the second pivot bearing 35 is formed by a flexible connecting section 59 between the closing unit 25 and the pull handle 29.

[0036] List of reference symbols:

[0037] 11 can lids

[0038] 13 metallic lid surface

[0039] 15 reusable opening system

[0040] 17 Beaded edge

[0041] 19 Locking piece

[0042] 21 Sealing frame

[0043] 25 Closing unit

[0044] 27 first pivot bearing

[0045] 29 Pull handle

[0046] 33 opening level

[0047] 35 second pivot bearing

[0048] 39 Base level

[0049] 40 Handling advantage

[0050] 41 outer circumference of the pull handle

[0051] 43 outer peripheral area of ​​the closing unit

[0052] 45 retaining rib

[0053] 47 Recess

[0054] 49 inner circumference of the pull handle

[0055] 50 chamfer

[0056] 51 radial outer sealing rib

[0057] 52 radial inner sealing rib

[0058] 53 radial outer receiving groove

[0059] 54 radial inner mounting groove

[0060] 55 plastic part

[0061] 57 flexible connecting section

[0062] 59 flexible connecting section

[0063] 60 ring axis

Claims

Claims Can lid (11) with a resealable opening, in particular for beverage cans, with a metallic lid surface (13) in which an opening area is formed, a sealing frame (21) made of plastic material which is connected to the metallic lid surface (13) and encloses the opening area, a closing unit (25) made of plastic material which is pivotally attached to the metallic lid surface (13) via a first pivot bearing (27) and is designed to close the opening area directly or by means of a closure piece (19) of the metallic lid surface (13) carried by the closing unit (25), wherein the sealing frame (21) and the closing unit (25) cooperate in a sealing manner via at least one sealing rib (51) and an associated receiving groove (53), and with an annular pull handle (29),which is connected to the closing unit (25) via a second pivot bearing (35) opposite the first pivot bearing (27), wherein the annular pull handle (29) is pivoted towards the closing unit (25) in a basic position and protrudes obliquely or transversely from the closing unit (25) in a pulled position, characterized in that the annular pull handle (29) radially surrounds the closing unit (25) in the basic position and thereby exerts a radially inwardly directed clamping effect on the closing unit (25), so that the sealing rib (51) is pressed against a wall of the receiving groove (53).

2. Can lid according to claim 1, characterized in that the sealing frame (21) and the closing unit (25) are designed such that when the annular pull handle (29) moves from the basic position in the direction of the pull position, air can pass through the arrangement of the sealing rib (51) and the receiving groove (53) due to the decreasing clamping effect.

3. Can lid according to claim 1 or 2, characterized in that the annular pull handle (29) is arranged at least substantially completely radially outside the closing unit (25) in the basic position.

4. Can lid according to one of the preceding claims, characterized in that the annular pull handle (29) and the closing unit (25) extend in a common base plane (39) when the annular pull handle (29) is in the basic position.

5. Can lid according to one of the preceding claims, characterized in that a locking device with at least one holding rib (45) and a complementarily shaped recess (47) is formed between an inner peripheral region (49) of the annular pull handle and the closing unit (25). Can lid according to claim 5, characterized in that the retaining rib (45) and the recess (47) extend along the entire inner peripheral region (49) of the annular pull handle (29). Can lid according to one of the preceding claims, characterized in that at least one handling projection (40) is arranged on an outer peripheral region (41) of the annular pull handle (29).Can end according to one of the preceding claims, characterized in that the sealing frame (21) and the closing unit (25) further cooperate in a sealing manner via a further sealing rib (52) which is located radially further inward than the other sealing rib (53), and an associated further receiving groove (54) which is located radially further inward than the other receiving groove (53), wherein upon opening of the can end, the further sealing rib (52) and the further receiving groove (54) still cooperate in a sealing manner even if detachment of the other sealing rib (51) and the other receiving groove (53) has already begun. Can end according to one of the preceding claims, characterized in that the annular pull handle (29) is made of plastic material. Can end according to one of the preceding claims, characterized in that the sealing frame (21), the closing unit (25), and the annular pull handle (29) are made of the same plastic material. Can lid according to one of the preceding claims, characterized in that the sealing frame (21), the closing unit (25) and the annular pull handle (29) are formed by a one-piece plastic part (55). Can lid according to one of the preceding claims, characterized in that the first pivot bearing (27) and the second pivot bearing (35) are connected by flexible connecting sections (57, 59) between the sealing frame (21 ) and the closing unit (25) on the one hand and the closing unit (25) and the annular pull handle (29) on the other hand.