EP0488420A1 - Closure for metal container and closure insert therefor - Google Patents

Abstract

The present invention relates to a closure on an upper end, preferably made of sheet metal, for a container, consisting of an upright hole collar (1) with its free edge (16) turned outwards and a closure insert (20) made of plastic which can be inserted into the hole collar (1), the hole collar (1) consisting of a first portion (2), which extends principally axially and is essentially cylindrical, and a flange portion (3) which extends essentially radially, and the free edge (16) of the flange portion (3) having a clear spacing from the surface of the upper end, which spacing is sufficient for the engagement of rolling or clinching tools below the flange portion (3). In order to design the closure in such a way that it can optionally be used as a roll-in or clinching closure or as a push-in closure and can also be produced with the smallest possible opening diameters, it is proposed according to the invention that the overall length of the hole collar (1), consisting of the first portion (2) and the flange portion (3), be less than 6 mm, measured in the axial and radial direction. In a fitting closure insert, at least one recess (30, 31) is provided on the outside of the radially inner U-shaped limb (6) of the closure foot (5) and/or on the inside, facing the two U-shaped limbs (6, 8), of the flange part (7) of the closure foot (5) connecting the U-shaped limbs (6, 8), which recess facilitates the radial pressing-away of the outer U-shaped limb (8) in the region of the projection (13). <IMAGE>

Description

The present invention relates to a closure on an upper plate made of sheet metal for a container, consisting of a raised collar with its free edge turned outwards and a plastic insert insert which can be inserted into the collar, the collar consisting of a mainly axially extending, essentially cylindrical, first section and a substantially radially extending flange section and wherein the free edge of the flange section from the surface of the top surface one for the engagement of clinching or rolling tools under the Flange section has sufficient clearance.

The present invention also relates to a closure insert made of plastic for biting into container openings with a perforated collar with an outwardly directed projection, the closure insert having a closure base with a U-shaped cross section, the radially outer U-leg on the inside of which has a radially inwardly directed projection has for reaching behind the outward projection on the hole collar of the container.

Such closures and closure inserts are known from practice.

In general, plastic closures used in openings on sheet metal casings or canisters have long been known both from practice and in writing, in particular also closures which have a raised perforated collar with an edge turned outwards. For example, reference is made to US Pat. No. 3,567,058.

For the purposes of the present application, an orientation of the closure is considered, as it is also shown in the figures. That is, the closure opening is made at the top of a container and the perforated collar is pulled up out of the surface of the container. The terms radial or outside and inside as well as axial refer to the hole geometry or the hole axis.

There are several ways to attach the plastic insert to the edge of the hole or the hole collar. In most cases, an insert socket of the closure insert has on its outside a circumferential projection or also individual projections at intervals, the radial extent of which protrudes beyond the container opening, so that when the closure is pressed into the opening, it is pressed radially inwards and after it has passed Snap the edge of the hole back outwards and lock it behind the edge of the hole.

Other fastening methods use the perforated collar itself as a fastening means, the upper edge of the hole being bent inward, for example, and thus providing a holding means for the latching engagement of corresponding latching cams, as well as the previously described hole edge. In other embodiments, from which the present invention is based, the edge of the perforated collar is flanged outwards. This flange edge is usually bent downward by approximately 180 ° or more, so as to form an annular circumferential, hook-shaped projection, behind which the corresponding holding means can snap in or snap in.

For this purpose, in some embodiments, plastic rings are slipped onto the perforated collar, which have an inwardly projecting bead, the inside diameter of which is smaller than the outside diameter of the turned edge, so that after the ring is forcibly pushed onto the perforated collar, this bead engages behind the turned flange edge. Such a plastic ring can either be formed in one piece with the closure insert, but can also be designed as a separate part holding the closure insert.

Specifically, for example, a hole is punched out of the top of a sheet metal can and the edge of this hole is pulled out essentially cylindrically from the surface of the top, and finally the free edge of the pulled-out part is bent outwards so that it forms an outwardly facing projection, which can reach behind an inward projection of a locking foot pushed onto the perforated collar. In so-called push-in closures, the closure foot is preferably U-shaped in cross section, the diameters of the closure foot and perforated collar being matched to one another such that, when the closure insert is fully assembled, its inner U-leg rests against the inner surface of the perforated collar, while the outer U-leg engages around the perforated collar and the flange part of the closure foot connecting the two U-legs rests on the upper edge of the perforated collar. In the closures already known, the edge of the perforated collar is usually flanged to a greater or lesser extent, so that its end section is directed backwards or downwards essentially in the axial direction. In cross section, the end of the perforated collar is thus bent more or less in a U-shape, the bent-back outer edge forming the aforementioned projection, which is engaged by the inward projection of the outer U-leg of the locking foot. The distance of the last-mentioned, inwardly directed projection from the flange part of the closure foot essentially corresponds to the distance from the upper edge of the perforated collar to its free, rearwardly bent edge, measured in the axial direction. The flange part thus rests on the upper edge of the perforated collar when the projection of the outer U-leg latches directly behind the projection formed by the bent edge of the perforated collar.

In a further embodiment, the closure insert is held on the hole collar not by a plastic ring, but by a metal ring. The closure insert then has, for example, an L-shaped insert socket, one L-leg of which is formed by a cylindrical part which can be inserted into the perforated collar and the other L-leg of which rests on the upper edge of the perforated collar. A likewise U-shaped or U-shaped metal ring with its radial L-leg is placed on this flange of the plastic insert placed, with its second, substantially cylindrical L-leg encompasses the flange of the plastic insert and also the flange edge of the perforated collar and projects downward in the axial direction. This cylindrical part of the metal ring is then either rolled up or clinched in the radial direction with compression of the material, so that it lies firmly beneath the turned-over flange edge on the outside of the cylindrical part of the perforated collar and thus holds the closure insert in a protected manner against any manipulation. The clinching and rolling in of metal rings is more complex and expensive than the insertion of locking plastic rings, but it also offers greater security against manipulation, ie against the opening of the closure, which cannot easily be determined afterwards, by loosening the retaining ring.

The desired degree of security against tampering depends on the one hand on the respective contents of the container on which the closure is located, but also on the transport, distribution and sales conditions for the filled containers. If the product is a sought-after scarce commodity and / or very expensive and is also stored unattended for a long time and under inadequate protective conditions, the risk of manipulation is of course greater than if the containers contain an easily available, inexpensive mass-produced product and also distribution channels and Storage are relatively safe.

In this respect, there is definitely a need, depending on the aforementioned conditions, to provide one and the same container type with a clinch or roll closure and sometimes with a so-called bump closure, i.e. a closure, the retaining ring is made of plastic, yields elastically when placed on the perforated collar and latches on the perforated collar or edge of the hole.

At the same time, closures of this type should of course be sealed as well as possible and be easy to assemble for reasons of cost savings.

Although the closure insert is described here in connection with a perforated collar formed from metal, the closure insert of the present invention can also be placed on other container openings which have a container neck with an outwardly projecting projection. The problems with which the present invention is concerned, however, arise primarily in connection with metal perforated collars.

A disadvantage of the known clinch and roll-in closures is that they are used to pull up the perforated collar, to fold the flange edge and to reach behind the downward flanged edge require a relatively large amount of material. In this case, a central hole that is only small compared to the final opening diameter can be punched out of the container surface, which is then widened by pulling up and turning over the hole collar. The edge of the hole is stretched the most. However, especially in the case of smaller hole diameters, the aspect ratio of the material in the region of the hole edge becomes so strong that commonly used materials for such sheet metal packages do not withstand and tear. It is therefore necessary to use special sheets suitable for deep drawing, which are correspondingly expensive.

When push-in closures are used, the closure inserts are generally injected into the container openings by automatic sealing machines. The term "bouncing" encompasses all closing processes in which the closure is locked onto the container by axial pressure with suitable counterparts. In the present case, the closure insert is pushed onto the perforated collar with the cross-sectionally U-shaped closure foot, deforms elastically until the inward projection of the outer U-leg has passed the outward projection of the perforated collar, and then snaps into it Starting position back so that the projections mentioned one after the other latch. It is understood that the inner diameter of the outer U-leg in the region of its projection is smaller than the outer diameter of the projection or flange of the perforated collar.

Even with a conical cut of the lower edge of the outer U-leg of the locking foot, which edge first comes into contact with the perforated collar, a certain force is required in order to move the projection of the outer U-leg over the projection or outer edge of the perforated collar. A common standard requirement is that a force of about 30 to 40 kp (approx. 300 to 400 N) should not be exceeded when such closures are smashed in, since there is otherwise fear of deformation or damage to the container.

Although one could increase the axial distance of the projection of the outer U-leg from the inner surface of the flange part, as well as the distance of the corresponding, opposite projection on the perforated collar to this surface, this design has other disadvantages which are avoided as far as possible in the present invention should be. In particular, in the case of small container openings with diameters of less than 40 mm, it is difficult or even impossible to implement an embodiment with correspondingly pulled out and strongly bent perforated collar edges. In addition, in the case of small hole diameters and otherwise unchanged differences, the diameter of the projections engaging one behind the other, the relative expansion and / or tilting of the outer U-leg is much stronger than with larger opening diameters. In addition, the fastening of the closure foot by means of a metallic clinch ring is not possible or is possible only with difficulty on such a perforated collar.

The present invention is therefore based on the object of designing a closure with the features mentioned in such a way that it can be used either as a clinch closure or as a snap-in closure and at the same time is easy to assemble, the usual requirements for tightness also being to be met and the Closure should cover the widest possible range of opening diameters. In particular, when using snap-in closures, the force required for the snap-in should be reduced, so that it can be pushed into corresponding container openings even at very short distances between the projection of the outer U-leg and the flange part without exceeding the generally required limit values, without the secure hold of the Closure on the perforated collar and its sealing engagement can be adversely affected.

With regard to the perforated collar, this object is achieved in that the total length of the perforated collar profile consisting of the first section and the flange section, measured in the axial and radial directions, is less than 6 mm.

In concrete terms, this means that the flange section cannot be turned 180 ° or more outwards and downwards, because too much material is then used for the flange section and the lower edge of the flange section would be too close above the container surface to engage clinching tools allow. Pushing on plastic rings is also relatively difficult if the clear distance between the flange edge and the container surface is too small.

The flange section therefore extends essentially only in the radial direction and is also kept as short as possible, so that there is sufficient material for the first, essentially cylindrical section of the perforated collar to ensure the axial distance of the flange edge from the container surface, which for attaching the clinch ring and snapping the plastic ring into place. A locking of the plastic ring on the inside of the hole behind the edge of the hole is therefore deliberately not provided in such a closure in order to better ensure the complete emptying of such a container.

Is the flange edge in a conventional manner in the axial direction or slightly beyond bent back, the length of the perforated collar profile must of course be increased accordingly, typically by about 1 mm. In this case too, however, the draw ratio remains low and in any case the perforated collar, due to its relatively short profile length, also protrudes only slightly from the plane of the top of the container. This facilitates the stacking of both the finished containers, which have an upper edge flanged at least at the same height, and the top shelf itself, which are manufactured and stored and transported separately from the containers. The perforated collars, which are important for the tightness of the closures, are less exposed to the risk of damage or deformation.

Regarding the closure insert for bouncing in, the object on which the invention is based is achieved in that at least one recess is provided on the outside of the radially inner leg and / or on the inside of the flange part of the closure foot connecting the U legs and facing the two U legs the radial pushing away of the outer U-leg in the area of its projection facilitates.

In the preferred embodiment of the invention, the total length of the perforated collar profile is only about 5.5 to 6 mm.

This length has proven to be sufficient for practical purposes, the total height of the perforated collar then being only about 3 to 4 mm. With an even smaller clear distance of the free flange edge to the top floor down to about 2 mm, the overall length of the perforated collar profile can be shortened accordingly.

An embodiment of the invention has proven to be particularly expedient, in which the first, essentially cylindrical section of the perforated collar is flared upwards. The plastic socket inserted into the perforated collar has a slightly larger diameter than the inside of the perforated collar to ensure a sealing engagement between the socket and the perforated collar. A corresponding counterpressure is exerted in the radial direction inwards by a clinching ring or a plastic ring which surrounds the perforated collar from the outside. The conical design of the perforated collar then ensures that this total pressure force, which is limited by the type of materials used, is concentrated on a narrow, ring-shaped circumferential contact area between the insert nozzle and the conical, first section, so that a seal can be ensured even more reliably than if the connection piece would contact the first cylindrical section of the same over the entire axial length of the perforated collar. Nonetheless, this section can easily be referred to as "substantially cylindrical" because of the desired effect Cone angle of approx. 5 ° is already sufficient for this part. Nevertheless, larger cone angles can also be realized.

The conical design of the first section of the perforated collar also has the advantage that the closure is centered more easily when inserted.

The clear distance between the edge of the flange section and the surface of the underlying top of the container should be at least 2 mm. In this way, there is sufficient space for clinching tools and for a plastic ring to be pushed on.

It is also expedient if, in order to enlarge the axial flange edge distance from the surface of the upper floor, a step lying essentially within the projection of the outer flange circumference surrounds the perforated collar. In this way, additional material of the axial and radial length of the perforated collar profile can be saved, so that the hole to be punched becomes even larger in relation to the final diameter of the top opening. In this way, the opening diameter of the finished hole of 27 mm can be practically realized without having to resort to deep-drawing material.

In the radial direction, the flange edge should extend at least 1.5 mm, preferably about 2 mm, beyond the inside diameter of the perforated collar. With a typically used material thickness of approx. 0.3 mm, there is then enough space under the essentially radially extending flange section to engage behind the clinching ring or plastic ring.

It has proven to be expedient if the flange section is slightly inclined towards the outside. This makes it easier to slide on a plastic ring and offers a more or less linear sealing surface for the flange of the plastic insert. At the same time, the resistance to bending up the flange edge is increased and the flange edge is not bent up beyond the horizontal plane even if it is pressed inwards in the radial direction by attaching the clinch ring or plastic ring.

It is also expedient if the flange edge has a punch burr on its lower free edge. This embodiment is particularly suitable for use in conjunction with an impacted plastic ring. This is because the plastic ring engages with the lower free edge of the flange edge, the cut surface or flange edge penetrating into the plastic and the plastic ring also being firmly hooked onto the punch burr.

In such an embodiment, the upper edge of the flange edge should be rounded as far as possible. This also makes it easier to slide on a plastic ring. Both the rounded edge and the punching ridge are produced in one and the same punching process. In the known, upwardly drawn perforated collar with the flange section turned outwards, the punching ridge, unless it is largely avoided or otherwise removed, is generally located on the upper edge of the flange edge. For the purposes of the present invention, the punching process must therefore be modified so that the punching burr actually occurs on the lower edge of the flange edge.

The objectives of the present invention are further achieved even better in that the plastic insert is suitably adapted to the perforated collar design, the plastic insert having, for example, a connecting piece sealingly engaging with the perforated collar and having an annular circumferential, radial bulge. The axial height of this radial bulge expediently coincides exactly with the axial height of the smallest inner diameter of the perforated collar in the fully assembled closure, so that here the sealing engagement limited to a narrow, annular area takes place with the maximum available contact pressure. However, a linear sealing engagement occurs through the ring-shaped, radial bulge even if the first section of the perforated collar is exactly cylindrical.

The ring-shaped, radial bulge is expediently formed by a double-conical configuration of the outside of the insert nozzle. In particular, the lower end of the neck, which is conical on the outside, has proven to be very useful for the simple insertion and centering of the plastic insert into the perforated collar. These good centering properties, which are further improved by the conical configuration of the first section of the perforated collar, facilitate the mechanical handling or manufacture of such closures.

For the embodiment with a clinch ring, the plastic insert expediently has an L-shaped foot ring, one L-leg of which is formed by an essentially cylindrical socket, the maximum outer diameter of which is slightly larger than the minimum inner diameter of the perforated collar, while the second L Leg is formed by a radial flange which rests on the flange section of the perforated collar and also has essentially the same outer diameter as this flange section. A clinch ring with an L-shaped or U-shaped profile can then be placed on the plastic flange with its radially inwardly projecting leg, while the other L-leg or the outer U-leg surrounds the plastic flange and the perforated collar in a cylindrical shape and is pressed against the outer wall of the first section of the perforated collar by clinching tools, thereby also pulling the plastic flange firmly onto the flange section of the perforated collar and holding it in place. In this way, a double seal is achieved, on the one hand between the socket of the foot ring and the first section of the perforated collar, and on the other hand between the flange of the foot ring and the flange section of the perforated collar, the compressive force for the latter being applied in the axial direction and independently of is the radial seal pressure of the former seal.

According to another embodiment of the present invention, the plastic insert has a U-shaped foot ring in profile, the two U-legs encompassing the inner and outer collar of the hole, the connecting piece forming the inner U-leg in sealing engagement with the inner surface of the first section of the perforated collar stands, while the connecting piece forming the other U-leg has a snap edge which engages behind the flange section of the perforated collar, the web connecting the two U-legs resting on the upper side of the flange section.

An embodiment of the invention has proven to be particularly expedient in which the outer connector is flared on its lower inside. This conical widening, namely at the smallest possible cone angle, makes it easier to push the plastic ring onto the perforated collar, since the snap edge on the outer connector must inevitably have a significantly smaller inner diameter than the outer diameter of the flange section of the perforated collar and the perforated collar supports the pressure opposes a considerable resistance in the radial direction. Since the outer collar in the axial direction can only be relatively short due to the hole collar, which is not very deep in the axial direction, the cone angle must, however, have a certain minimum size so that the collar actually encompasses the edge of the collar when it is put on. With the help of the conical cut of the outer socket as well as the slight inclination of the flange section downwards and the rounding of the upper edge of the flange, it is possible to slide the plastic ring on without too much effort. Thereafter, however, a loosening of the plastic ring is only possible with considerable effort because of the special profile of the snap edge or the inwardly projecting projection of the outer connector.

The slightly conical shape of the first section of the perforated collar is also helpful here, since the inner connecting piece in the upper, further part of the perforated collar does not yet lie against the inside of this first section and thus the radial inward pressing of the flange edge no additional resistance.

The snap edge of the outer connector preferably has the shape of an annular bead running around the inside of the outer connector. This ring bead opens in profile on its upper side at a right or only a slight obtuse angle on the inner surface of the outer connector and in its lower region merges directly into the conical part of the lower inner wall of the outer connector.

It goes without saying that all of the features described above and not directly related to the length of the perforated collar profile can also be sensibly and with similar effects if the axial and radial extension of the perforated collar profile is more than 6 mm.

When the above-mentioned closure inserts are pushed in, i.e. When the inwardly projecting projection of the outer U-leg is pushed radially so that it slides over the outwardly projecting projection of the perforated collar, various mechanical force effects can be clearly taken into account. On the one hand, it can be seen from the U-shaped cross section (see FIGS. 8 and 9) that the pushing of the locking foot onto the perforated collar is linked to a bending apart of the two U-legs of the locking foot, to which this resists an elastic resistance. Furthermore, since this U-shaped cross-section extends essentially over the entire circumference of the ring, and of course the inwardly projecting projection of the outer U-leg can possibly also be designed intermittently, pushing on the locking foot also requires an expansion thereof, since the one mentioned The projection of the outer U-leg has a smaller diameter than the outer edge or the outwardly pointing projection of the perforated collar.

The force required to bend the two U-legs apart naturally depends on the starting point of this force, ie on the length of the lever arm between this starting point and a pivot point in the region of the flange part which cannot be exactly defined. The starting point of this force is just the point of contact of the projection of the perforated collar with the (generally conical) inner surface of the outer U-leg below the projection. Thus, the further the locking foot is pushed onto the perforated collar, the closer this point of contact comes to the point of the rotary movement and the shorter the lever arm. This shortening of the lever arm continues until the two projections lie exactly opposite one another, as shown in FIG. 2. At this point you will find a relatively short lever arm, whereby the two U-legs are maximally bent apart, that is a maximum elastic restoring force acts. After this point is exceeded, the lever arm is shortened further, but the elastic restoring force decreases more quickly, since the two U-legs can now move towards each other again. The exact course of force naturally depends on the exact geometric shape of the two opposite projections.

A recess either in the outer surface of the inner U-leg, which faces the perforated collar, or in the side of the flange part facing the perforated collar, has different effects on the force required to push the projection of the outer U-leg away, depending on the arrangement and size. Basically, with such a recess a weakening of the inner U-leg or the flange part is linked due to a reduced material thickness, so that for this reason alone the maximum force required for radially pushing away the above-mentioned projection is reduced, since the radial pushing away of this projection also always includes an expansion of the flange part and the inner U-leg.

In addition, however, additional effects can be achieved by a favorable geometric arrangement and design of corresponding recesses, which reduce the maximum force required to bounce the closure insert.

If a recess is provided on the outside of the inner U-leg in such a way that there is an increasingly greater clearance between this leg and the perforated collar, especially in the vicinity of the flange part, the inner U-leg can move radially into this area Move outward when a corresponding pull is exerted on the inner U-leg via the flange part, which results from the pushing away of the projection in the radial direction to the outside. In a conventional closure design, however, the outside of the inner U-leg already touched the perforated collar before the projection of the outer leg was pushed over the outwardly projecting projection of the perforated collar, so that the inner leg undergoes a further radial outward movement or expansion was prevented and thus also opposed the radial outward movement of the outer U-leg or the corresponding projection a considerable resistance. According to another embodiment of the invention, a recess is provided in the flange part, which extends in the axial direction from the surface of the flange part facing the perforated collar into the flange part. This advantageously has the effect that the pivot point with respect to the bending apart of the two U-legs is shifted into the area beyond the depth of the recess, so that the leverage ratios for the This makes exercise more economical. Of course, both features, ie recesses in the flange part and in the inner leg of the locking foot, can also be easily combined with one another.

In this way it is possible to penetrate the closure insert into those container openings whose perforated collar has a flange edge which is only slightly bent back. The projection on the outer U-leg is relatively close to the flange part in order to secure the closure in a position in which the flange part rests on the upper edge of the perforated collar. The outer U-leg of the closure foot can and must be kept short in the axial direction if the perforated collar protrudes only slightly from the plane of the container top, which precludes evasion to an even steeper conical cut of the inside of the outer U-leg.

In a preferred embodiment of the invention, an essentially completely circumferential incision is provided on the mentioned inner surface of the flange part. The incision therefore only needs to be essentially completely circumferential, because short interruptions or webs that bridge the incision have no significant influence on the overall displacement of the pivot point.

It has proven to be expedient if the incision extends in the axial direction at least up to half the thickness of the flange part. With extremely thick flange parts, the incision can reach a depth that corresponds to 2/3 to 3/4 the thickness of the flange part. As a result, the lever for the power arm is extended by a corresponding amount.

The thickness of the flange part outside the incision should preferably be between 1.5 and 3 mm.

According to another embodiment of the invention, the recess on the inner U-leg is formed by a, in the direction of the flange part, conical tapering of the outside of the inner U-leg, the maximum clear distance between the conically tapered section and the essentially cylindrical inner wall of the perforated collar approximately corresponds to at least the difference in diameter of the projection of the perforated collar to the projection of the outer U-leg. This enables the inner U-leg to allow the required radial outward movement of the projection of the outer U-leg simply by its tilting (viewed in cross section). It is understood that this is simultaneously an expansion of the outer U-leg, the flange part and at least that of the flange part adjacent area of the inner U-leg needs, which form a ring.

The present invention proves to be particularly expedient if the axial distance of the projection of the outer U-leg to the inner surface of the flange part not covered by a recess is less than 3 mm, preferably less than 2 or even 1 mm. This ensures the play-free hold on the edges of the perforated collar, which are only slightly bent, while at the same time the inner surface of the flange part rests on the upper edge of the perforated collar.

In addition, the new closure insert can also be used expediently at all other container openings which have an essentially cylindrical connection piece or "perforated collar" with an outward projection, which the inward projection of the outer U-leg or the outer connection piece of the closure insert can reach behind.

An embodiment of the invention has proven to be particularly advantageous in which the projection on the inside of the outer U-leg is formed by a double-conical design of this inside. Specifically speaking, the radius of the inner surface of the outer U-leg decreases continuously, starting from the tip of the projection in the axial direction both towards the flange part and away from the flange part. It is expedient if the decrease in the radius towards the flange part takes place faster than away from it, that is, if in other words the cone angle of the conical section remote from the flange part is smaller than the cone angle of the conical section facing the flange part. The cone angle of the remote section should preferably be at most half the cone angle of the other section. The cone angle is considered to be half the opening angle of a cone with the same side surface inclination.

Figur 1

einen Schnitt durch eine Axialebene des Verschlusses in einer ersten Ausführungsform,

Figur 2

einen vergrößerten Ausschnitt aus Figur 1,

Figur 3

einen Schnitt entsprechend Figur 1 durch eine zweite Ausführungsform,

Figur 4

einen vergrößerten Ausschnitt aus Figur 3,

Figur 5

den Lochkragen für die beiden in den Figuren 1 bis 4 dargestellten Ausführungsformen,

Figur 6

einen vergrößerten Ausschnitt aus Figur 5 und

Figur 7

einen vergrößert dargestellten Ausschnitt eines Verschlußeinsatzes der in den Figuren 3 und 4 dargestellten Ausführungsform ohne Lochkragen.

Figuren 8 bis 10

den Querschnitt durch einen Verschlußfuß einer ersten Ausführungsform in drei verschiedenen Stadien des Einprellens,

Figuren 11 und 12

einen Querschnitt durch den Verschlußfuß einer zweiten Ausführungsform in zwei den Fig. 2 und 3 entsprechenden Stadien,

Further advantages, features and possible uses of the present invention will become clear from the following description of preferred embodiments and the associated figures. Show it:

Figure 1

2 shows a section through an axial plane of the closure in a first embodiment,

Figure 2

2 shows an enlarged detail from FIG. 1,

Figure 3

2 shows a section corresponding to FIG. 1 through a second embodiment,

Figure 4

3 shows an enlarged detail from FIG. 3,

Figure 5

the perforated collar for the two embodiments shown in Figures 1 to 4,

Figure 6

an enlarged section of Figure 5 and

Figure 7

an enlarged section of a closure insert of the embodiment shown in Figures 3 and 4 without perforated collar.

Figures 8 to 10

3 shows the cross section through a locking foot of a first embodiment in three different stages of bouncing,

Figures 11 and 12

3 shows a cross section through the locking foot of a second embodiment in two stages corresponding to FIGS. 2 and 3,

Figures 13 and 14 two cross sections through complete closures.

In all figures, the perforated collar is generally designated 1 and the closure insert 20.

The perforated collar 1 is pulled out of the top panel 4. Continuous casting material of normal quality is used for the sheet metal of the top floor 4. The sheet thickness is approximately 0.3 mm in embodiments already produced in practice, of course, thinner or thicker sheets can also be used.

The various embodiments are shown in FIGS. 1, 3 and 5 on a 2: 1 scale, in the remaining figures on a 5: 1 scale. It goes without saying that for the purposes of the present invention, compliance with the dimensions is not important, but the true-to-scale reproduction of specifically produced embodiments makes it easier to quantify the presence of the claimed features in detail.

The perforated collar 1 consists of an essentially cylindrical first section 2 and an essentially radial flange section 3. However, it can be seen that the first section 2 is not exactly cylindrical, but slightly conical. The practical cone angle is 5 °, but larger cone angles of up to 20 ° can be regarded as a slight conical widening in the sense of the present application.

The flange section 3 also does not run in the exact radial direction, but is slightly inclined to the outside.

In Figure 6, further details of the perforated collar 1 are designated and shown. The axial and radial length of the perforated collar profile is the measure which results in FIG. 6 as the total length of the sections 2 and 3, the beginning of the first subsection 2 starting approximately with the cut with the dashed line 14. The raised first section 2 upstream of a stage 11 which, seen in the radial direction, is still essentially within the projection of the radius of the flange edge 16. The step 11 advantageously increases the distance between the flange edge 16 and the top floor 4 without the perforated collar profile having to be lengthened as a result.

In the example shown, the radial and axial length of the perforated collar profile is approximately 5 mm. The clear distance between the flange edge 16 and the surface of the top floor 4 is outside the step 11 about 3.5 mm, the step height is about 1 mm.

In the radial direction, the flange edge 16 extends approximately 2 mm further than the inside diameter of the perforated collar 1. The depth of the undercut resulting from this on the outside of the perforated collar 1 is approximately 1.5 mm. This is sufficient to securely attach a clinching ring to the flange section 3. For the projection 13, too, there is a sufficiently large depth, since the inside diameter of the outer connector 8 along the projection 13 must not fall too far below the outside diameter of the flange edge 16 in order to be able to be pushed over the flange edge 16 at all.

In Figures 1 and 2 a so-called clinch or roll closure is shown. For the convenient attachment of the curling ring or clinch ring 12, the foot ring 5 of the closure insert 20, which comes into direct contact with the perforated collar 1, consists of an L-shaped, possibly also U-shaped section, which has an essentially cylindrical connecting piece 6 has essentially radial flange 7.

The closure insert 20 is thus first inserted with the foot ring 5 into the perforated collar 1 or placed thereon. A metal ring 12 with a U-shaped cross section is then placed on the flange 7 of the foot ring 5. The pray U-legs of the clinch ring 12 are of different lengths, the outer leg being the longer of the two, which protrudes clearly below the flange edge 16 of the flange section 3. Before clinching, the ring 12 has the position shown in broken lines, after the clinching the longer U-leg is pressed firmly under the flange section 3 onto the perforated collar 1. As a result, the flange 7 of the foot ring 5 is pressed onto the flange section 3 from above.

Due to the conical shape of the first section 2 of the perforated collar 1 and additionally due to the cross-sectional design of the connector 6, as is also shown separately for the second embodiment in Figure 7, the available contact force between the outer surface of the connector 6 and the inner surface of the first section 2 to a narrow, annular strips concentrated, although in the drawings the area of contact between the perforated collar and the socket 6 is shown relatively broad, the majority of the contact pressure is nevertheless concentrated in the area where the difference between the outer diameter of the socket 6 and the inner diameter of the perforated collar 1 is greatest . For this purpose, the connecting piece 6 has a ring-shaped bulge 9, which is shown separately in FIG. 7 for the second embodiment, but is also present in the embodiment shown in FIGS. 1 and 2.

This bulge 9 is the result of a double-conical design of the connector 6, the lower conical profile of the connector 6 serving above all to make it easier to insert and center the plastic insert 20 in the perforated collar 1. As can be seen in the figures, the connecting piece 6 is extended in segments beyond the cross-hatched cross section, so that this results in even better centering properties. The sectional plane shown in the figures runs straight between such extensions, these interruptions primarily serving to ensure complete emptying of the container when the closure is tilted down.

The particular advantage of the closure according to the invention lies in the fact that the special design of the perforated collar with a relatively low draw ratio and a flange section 3 which is only slightly angled downwards enables both the attachment of a clinching ring 12 and the fitting of a U-shaped foot ring 5 of a closure insert 20. This second possibility is shown in FIGS. 3 and 4, FIG. 7 showing the same closure without the perforated collar 1. The foot ring 5 of this closure insert 20 'is U-shaped in profile or in cross section and consists of an essentially cylindrical, but on the outside in turn slightly double conical socket 6, a second outer U-leg 8, which is essentially parallel thereto, and the Connecting web or flange 7. The engagement between the connector 6 or the flange or web 7 and the perforated collar 1 is practically the same as in the embodiment described first. This closure insert 20 'is also not latched on the inside of the perforated collar but is fastened to the flange section 3. For this purpose, the outer socket 8 has an inwardly projecting bead 13. This is more or less partially circular in cross section, but merges directly on its underside into a weakly conical surface 10 of the outer connector 8, which extends practically to the end of the connector. The bead 13 can also consist of individual interrupted, nose-like projections. The only slightly conical surface 10 allows the foot ring 5 to be pushed onto the perforated collar 1 without too much force and to be pushed over the flange edge 16 with the projection 13. So with the weak conical design of the lower inner surface 10 of the socket 8 this completely surrounds the flange edge 16 when it is pushed onto the perforated collar 1, at least in its lower region, the socket 8 must have a certain axial minimum length, so that for this reason, in this embodiment too, a corresponding distance of the flange edge 16 from the top floor 4 is desirable and an advantage.

Sliding it on is made even easier by the fact that the flange section 3 is slightly sloping towards the outside and that the upper edge 16 ″ of the flange edge 16 is rounded. The lower edge 16 'of the flange edge 16, however, consists of a stamping ridge. As soon as the U-shaped foot ring 5 has been pushed completely onto the perforated collar 1, the flange edge 16 penetrates into the inner surface of the connector 8 above the projection 13 and holds, among other things. via the punching ridge 16 'the foot ring 5 firmly in place, the projection 13 still providing additional protection against deliberate loosening of the closure insert. So that the flange edge 16 penetrates essentially along its entire circumference into the inner surface of the nozzle 8, the diameter of the inner surface of the nozzle 8 is also smaller above the projection 13 than the outer diameter of the flange edge 16.

An additional seal is also achieved along the flange edge 16, which is independent of the seal between the connector 6 and the first section 2 of the perforated collar 1.

The comparatively short length of the perforated collar profile makes it possible to produce perforated collars with a finished inner diameter of, for example, only 27 mm, the perforated collar otherwise having all the features shown in the figures. Advantageously, not only different plastic inserts can be attached to the same type of perforated collar, but this type of perforated collar is also suitable for very different, in particular for small diameters.

8 shows in cross section the edge of a container opening 40, which is designed as a raised perforated collar 1 with an outwardly turned flange edge which, in the sense of the present application, forms a projection or flange 9 pointing outward in the radial direction. Above the perforated collar 1 is also shown in cross-section and immediately at the beginning of a bumping operation a locking foot 5 which appears U-shaped in cross-section, with an inner U-leg 6, an outer U-leg 8 and a flange part connecting the two U-legs 7. Complete closures, consisting of a closure insert 20 and a screwed-on closure cap 41, are shown in axial section in FIGS. 13 and 14, with FIG. 13 only differing from FIG. 3 by the recess 30 shown.

The closure inserts 20 essentially consist of an inner closure part 2, which can have different shapes that are not important for the purposes of the present application, and of the closure foot 5 already mentioned and shown in more detail in FIGS. 8 to 12.

In all figures, the position of the closure inserts 20 or the closure feet 5 corresponds to an alignment centered with the container opening 40. Corresponding cuts at any point on the edge of the hole do not differ.

In an automatic filling system or an injection machine, the closure insert is pressed with a force acting in the direction of arrow 36 from above with the inner closure part and the inner U-leg 6 into the container opening 40, the perforated collar 1 with the flange 3 being inserted into the U-legs 6, 8 and the flange part 7 formed groove 35 of the locking foot 5 slides into it. The minimum inner diameter of the outer U-leg 8 is defined by the bead-like circumferential projection 13. This inner diameter is smaller by the amount x than the outer diameter of the perforated collar 1, measured on the outer edge of the flange 3 or projection 16.

From the projection 13 of the outer U-leg 8 extends from a conical surface 10, the radius increases with increasing axial distance from the flange part 7, so that the inner diameter of the U-leg 8 is finally larger at its lower end than the outer radius of the Flange edge or projection 16. The lower edge of the inner U-leg 4 is formed intermittently, the axial section shown in the figures running straight along a gap between two extensions 6 'of the U-leg 6. The lower outer edge of these extensions 6 'is beveled conically, so that the closure foot 5 with its inner U-leg 6 or 6' can be easily centered in the perforated collar 1.

Under the action of the force acting in the direction of arrow 36, the closure foot 5 now slides with its inner U-leg 6 into the opening 40 of the container below, the perforated collar 1 simultaneously entering the groove 35 of the closure foot 5. After a short axial advance of the locking foot 5, the flange edge 16 comes into contact with the conical surface 10, so that a force is exerted on the surface 10 and the outer U-leg 8 in the radial direction to the outside. The locking foot 5, which is made of an elastic plastic material, provides a certain resistance to this force. The pressure force to be exerted in the direction of arrow 36 essentially depends on the geometry of the closure foot 5, in particular on the cone angle of the surface 10, the diameter difference x of the projections 16 and 13, the material thicknesses of the U-legs 6, 8 and the flange part 7 and the distance of the point of application of the projection 16 on the conical surface 10 to a pivot point in the flange part 7 which cannot be exactly defined, but which is shown in FIG. 8 shown embodiment is in the vicinity of the inner surface 34 of the flange 7. Since the double-conical inner U-leg 6 rests with its sealing bead on the inner surface of the perforated collar 1 and, on the other hand, the outer U-leg 8 is pressed outwards due to the abutment of the projection 16 on the conical surface 10, the two U - Swing legs 6,8 relative to each other around said pivot point.

Obviously, the force to be injected in the direction of the arrow 36 in the direction of the arrow 36 becomes maximal when the flange edge 16 reaches the projection 13, since then the relative tilting of the two U-legs 6, 8 is greatest, the required expansion of the closure foot 5 maximum and at the same time the effective lever with respect to the mentioned pivot point is very small. During the further movement of the projection 16 along the second conical surface 33, the lever length decreases even further, but in this area the further downward movement of the ring is supported by the elastic restoring forces, so that no additional pressure is required from above and the locking foot has finally assumed the end position shown in FIG. 10. 10 also indicates that the outside diameter of the projection 16 is still larger than the maximum inside diameter in the region of the undercut formed behind the projection 13. The flange edge 16 is thus somewhat pressed into the plastic material of the closure foot. By pressing the projection 16 into the outer U-leg 8, an additional seal is obtained between the closure foot 5 and the container.

11 and 12 illustrate the bumping in the stages of FIGS. 9 and 10 just discussed for another embodiment of the invention.

In this embodiment, an incision 30 is provided in the form of a groove running around the entire circumference of the closure foot 5 in the inner surface 34 of the flange part 7, through which the effective lever when the two U-legs 6, 8 are pressed apart further upwards into the area above of the incision 30 is shifted. The pressing apart of the two legs 6, 8 is then linked to a widening of the incision or of the groove 30, as can be clearly seen in FIG. 11. In particular, in this embodiment, the flange part 7 and the inner U-leg 6 are stretched less when the ring is injected, so that the force required for the injection is reduced in the desired manner.

In addition to the incision 30, as can be seen most clearly in FIG. 12, the recess 31 is also provided on the outside of the inner U-leg 6, which, however, as FIG. 11 shows, is only partially used because the inner U-leg 6 in the region of the recess 31 does not come into contact with the perforated collar 1 anyway. The cutout 31 could therefore be less pronounced than in the embodiment described first in accordance with FIGS. 8 to 10 or could be omitted entirely.

Fig. 13 shows the implementation of the present invention as an axial section through a bellows closure. The closure insert 20 consists of the closure inner part 22 and the closure foot 5, on the specific embodiment of which the present invention is directed. The inner closure part consists of a bellows which can be pulled out and attached to the inner U-leg 6 and which is connected at its other end to a pouring spout with a screw thread. A screw cap 41 with a bracket 42 is screwed onto this screw thread. By folding up the bracket 42 and pulling it upward in the vertical direction, the pouring spout is also pulled out of the container opening with the screw cap 41, the bellows being turned outwards. In addition, you can still see a seal closing the inner cross section of the pouring spout. However, these details are irrelevant to the present invention, as is also shown in the example in FIG. 14, in which the pouring spout is formed directly by the inner U-leg 6 and the outer leg 8 is extended upwards by a cylindrical holder to form with a snap edge for a snap edge lid. The present closure insert is also not limited to container openings with metal perforated collars, nor to the special perforated collar shapes, as shown above. Rather, the invention is applicable to all closure inserts which are fastened by bumping, ie by the mutual engagement of two projections, one of which is arranged on the inside of a U-leg of a cross-sectionally U-shaped closure foot and the other on the perforated collar or container neck is. In all of these closures, the force required for the insertion is reduced by providing the cutouts according to the invention. However, this effect is particularly advantageous when, as in the illustrated embodiments, the force required for bouncing in would be relatively high without the measures according to the invention due to the special closure geometry.

Reference symbol list

1

Perforated collar

2nd

Subsection

3rd

Flange section

4th

Top panel

5

Locking foot

6

Support

6 '

Extensions

7

Flange part

8th

Outer socket, U-leg

9

head Start

10th

area

11

step

12

Clinching ring, metal ring

13

Head start, bead

14

line

16

Flange edge

16 ''

upper edge of the flange edge 16

16 '

Punching ridge

20, 20 '

Locking insert

22

Inner closure part

30th

incision

31

Recess

33

area

34

Inner surface

35

Groove

36

arrow

40

Container opening

41

Sealing cap, screw cap

42

hanger

Claims (28)

Closure on a top plate (4) made of sheet metal for a container, consisting of a raised, with its free edge (16) facing outwardly perforated collar (1) and a plastic insert insert (20) which can be inserted into the perforated collar (1), whereby the perforated collar (1) consists of a mainly axially extending, substantially cylindrical, first section (2) and a substantially radially extending flange section (3) and wherein the free edge (16) of the flange section (3) from the surface of the Upper floor has a sufficient clearance for the engagement of rolling or clinching tools under the flange section (3), characterized in that the total length of the perforated collar (1) consisting of the first section (2) and the flange section (3), measured in axial and radial direction, is less than 6 mm. Closure according to claim 1, characterized in that the total length of the perforated collar or perforated collar profile is approximately 5 mm. Closure according to claim 1 or 2, characterized in that the first, essentially cylindrical section (2) is slightly conically widened towards the outside of the perforated collar (1). Closure according to one of claims 1 to 3, characterized in that the clear distance between the free flange edge (16) and the surface of the upper floor (4) lying below in the axial direction is at least 2 mm. Closure according to claim 4, characterized in that, in order to increase the clear axial flange edge distance from the top surface, a raised step (11) in the top floor, which lies essentially within the projection of the outer flange radius, surrounds the perforated collar (1). Closure according to one of claims 1 to 5, characterized in that the flange edge (16) extends in the radial direction by at least 1.5 mm, preferably by about 2 mm, beyond the inside diameter of the perforated collar (1). Closure according to one of claims 1 to 6, characterized in that the flange section (3) is slightly inclined outwards towards the top floor (4). Closure according to one of claims 1 to 7, characterized in that the flange edge (16) has a punch burr (16 ') on its lower free edge. Closure according to one of claims 1 to 8, characterized in that the flange edge (16) is rounded at the upper free edge (16 ''). Closure according to one of claims 1 to 9, characterized in that the plastic insert (20) has a connecting piece (6) sealingly engaging with the perforated collar (1) and having an annular, radial bulge. Closure according to one of claims 1 to 10, characterized in that the bulge (9) is formed by the double-conical outside of the connecting piece (6). Closure according to claim 10 or 11, characterized in that the plastic insert (20) has an L-shaped foot ring, one L-leg of which is formed by an essentially cylindrical socket, the maximum outer diameter of which is somewhat larger than the inner diameter of the perforated collar (1), while the second L-leg is formed by a radial flange part (7) which rests on the flange section (3) of the perforated collar (1) and has essentially the same outer diameter as the flange section (3). Closure according to claim 10 or 11, characterized in that the plastic insert (20) has a U-shaped foot ring, the two U-legs encompassing the perforated collar (1), the connecting piece (6) forming the inner U-leg in sealing engagement with the inner surface of the first section (2) of the perforated collar (1), while the other U-leg forming outer connection piece (8) has a snap edge which engages behind the flange section (3) of the perforated collar (1), and the Flange part (7) of the U-profile rests on the flange section (3). Closure according to claim 13, characterized in that the outer socket (8) is flared on its lower inside (10). Closure according to claim 13 or 14, characterized in that the snap edge of the outer connector is provided by an annular bead (13) provided on the inside thereof. Closure according to one of claims 13 to 15, characterized in that the The inner diameter of the outer socket (8) above the ring bead (13) is slightly smaller than the outer diameter of the flange section (3). Closure insert made of plastic for biting into container openings (40) with a perforated collar (1) with an outwardly directed projection (16), the closure insert (20) having a closure foot (5) with a U-shaped cross section, the radially outer U-leg (8) has on its inside a radially inward projection (13) for engaging behind the outward projection (16) on the perforated collar (1) of the container, characterized in that on the outside of the radially inner U-leg (6) of the closure foot (5) and / or on the inside of the flange part (7) of the closure foot (5) connecting the U-legs (6, 8) and facing the two U-legs (6, 8) at least one recess (30, 31) is provided, which facilitates the radial pushing away of the outer U-leg (8) in the region of the projection (13). Closure insert according to claim 17, characterized in that an essentially completely circumferential incision (30) is provided as a recess on the inside of the flange part (7). Closure insert according to claim 18, characterized in that the incision (30) extends in the axial direction up to half the thickness (a) of the flange part (7). Closure insert according to claim 19, characterized in that the incision extends in the axial direction by up to 2/3 to 3/4 of the thickness (a) of the flange part (7). Closure insert according to one of claims 17 to 20, characterized in that the thickness (a) of the flange part (7) is between 2 and 4 mm. Closure insert according to one of claims 17 to 21, characterized in that the recess (31) is designed as an undercut behind a bead-like circumferential projection which is provided as a sealing bead for contact with the inner wall of the perforated collar (1), the clear distance of the inner U-leg (6) in the region of the undercut to the inner wall of the perforated collar (1) approximately corresponds to at least the diameter difference of the projection (16) of the perforated collar (1) to the projection (13) of the outer U-leg (8). Closure insert according to one of claims 17 to 21, characterized in that the recess (31) on the inner U-leg (6) is formed by a, in the direction of the flange part (7), conical taper of the outside of the inner U-leg (5), the maximum clear distance (x) of the conical tapered section to the substantially cylindrical inner wall of the perforated collar (1) approximately corresponds to the difference in diameter of the projection (16) of the perforated collar (1) to the projection (13) of the outer U-leg (8). Closure insert according to claim 23, characterized in that the inner U-leg (6) is double conical on its radially outer side to form an annular sealing bead. Closure insert according to one of claims 17 to 24, characterized in that the axial distance from the projection (13) of the outer U-leg (8) to the inner surface of the flange part (7) not covered by a recess (30) is less than 2 mm, preferably is less than 1 mm. Locking insert according to one of claims 17 to 25, characterized in that the projection (13) on the inside of the outer U-leg (8) of the locking foot (5) is formed by a double-conical design of this inside. Closure insert according to claim 26, characterized in that the cone angle of the conical section remote from the flange part (7) is smaller than the cone angle of the conical section facing the flange part (7) and is at most approximately half or less of the latter. Closure insert according to one of claims 17 to 27, characterized in that the maximum inside diameter of the section of the outer U-leg (8) lying between the projection (13) and the flange part (7) is smaller than the outside diameter of the projection (16) of the Perforated collar (1).

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