EP0081250B1 - U-shaped clip formed from a strip-like material - Google Patents

Description

The invention relates to a U-shaped closure clip made of band-shaped material for tubes and bags, the clip consisting of a clip base and two legs and the leg ends of the clip being bent outwards and forming a connecting web through which the clip can be separated in a strip with others Brackets are connected and the inner radius of the connecting arches between the bottom of the bracket and the legs is at least as large as the thickness of the band-shaped material.

The packaging braid of a bag or tube is closed with these clips in such a way that first a clip with its clip base is inserted into a suitable die with the legs pointing upwards, and then the packaging sleeve to be sealed, usually gathered or twisted into a braid, is placed in the clip is what a stamp approaches the die from above and the clip separates from the strip and closes (DE-PS 1 078 495, 1 761 616 and 2 606 658).

This type of sealing clip made of band-shaped material places ever greater demands on locking force, slip resistance and a tight seal, which are particularly necessary for sealing air-impermeable casings. Different forces act on such a locking clip (cf. DE-PS 2 606 658, column 1/2). With these locking clips, the locking force and the slip resistance were increased and the locking force was improved in that the band-shaped material in the area of the clip base and the legs on the outer edges was partially folded inwards to form two beads running along these outer edges. However, these closing clips have a small radius of the connecting arches between the clip base and clip leg. As a result, the braid is not always pressed together sufficiently tightly at these points in the closed state, as a result of which, in certain cases, capillary formation can occur at these points, which in turn can lead to leaks and thus to grease escaping or air entry at the closing clip. In addition, the use of this locking clip only makes sense if sausages with a relatively large diameter, for example from 60 mm, are to be sealed.

The invention is therefore based on the object of improving closure clips of the generic type in such a way that, in particular when using air-impermeable casings, e.g. made of polyvenylidene chloride, polyamide, polyester or fiber casings coated with plastic on the inside or outside, do not slip on the relatively smooth surface of the braid and form an essentially fat and airtight seal and can also be used sensibly with sausages of smaller caliber.

This object is achieved according to the invention in that, in the case of a closure clip of the generic type, a preferably inwardly pointing, approximately centrally arranged stiffening piece is provided, which is limited to the area of the clip base and the connecting bends. The inner radius of the connecting arches between the clamp base and the leg should preferably be at least twice as large as the thickness of the band-shaped material.

The combination of the measures proposed to solve the task leads to a significantly improved locking clip. The increase in the inner radius of the connecting bends between the clip base and the leg compared to the conventional closing clips means that there are no longer any corners between the clip base and the leg. This ensures that the sausage braid completely fills the closed clip so that it is firmly pressed together over its entire surface. This avoids the risk of capillary formation and essentially eliminates grease leakage or air entry at the locking clip.

The fact that a straight clamp base is retained means that, particularly with closure clips with relatively long legs for closing large-caliber sausages, it is achieved that, after being separated from the clip strip, they do not turn away in the die during the closing process. The stiffening bead, which is limited to the area of the clip base and the connecting arches, increases the resistance to bending the closing clip and, if it is preferably directed inwards, additionally increases the slip resistance. By restricting the bead to the area of the clip base and the connecting bends to the leg, the deformation resistance of the clip legs is kept as low as possible in the upper area during the closing process in order to enable a machine-friendly and intestinal low closing force.

From GB-A-774 267, Fig. 6-8, locking clips are known which are arranged laterally and have outwardly facing beads. However, it cannot be deduced from this that the above-mentioned advantages are achieved by stiffening beads which are preferably directed inward and are arranged approximately in the center in combination with the generic features.

Overall, the measures according to the invention achieve a closure clip with significantly improved properties while maintaining the same material expenditure, or material can be saved with the closure force remaining the same. In relation to a locking clip without the large radii of the connecting bends and without the inner bead in the area under load, the locking force could be increased by around 20%, the clip-slip ratio (start of slipping at a burst pressure value in kp / mm ² ) by around 20% and the fat tightness can be improved by about 30%.

The closure clip according to the invention is particularly suitable for closing cooked sausages treated in an autoclave, in which the internal pressure of the sausage rises sharply, of cooked sausages that are cooked or scalded and of sausages that should have a long shelf life. A special use is also the sealing of externally coated fiber casings, the coating of which is so smooth that closures can easily slip off during cooking due to the filling pressure or increasing internal pressure.

The object on which the invention is based, in particular in the case of sausages of smaller caliber, that is to say less than about 50 mm in diameter, can be achieved by a modification of the invention in such a way that the connecting bends form a round arch with a common radius with the clamp base. Because of the short legs, there is no risk that the locking clip will turn away in the die when it is cut and closed.

Individual clips for closing sausage casings are known, in which the clip base is designed as a round arch (US Pat. No. 2,972,791, 3,017,638). This clip has two outwardly directed beads, which, however, extend into the region of the inwardly bent legs. These closure clips do not correspond to the generic clips because they cannot be produced as clip strips connected together at the ends. The long beads also require a high closing force. Another known single clip (US Pat. No. 3,061,838) also has a round clip base, but contains a stiffening by flanging the outer edges. This closure clip would also be unsuitable for the production of the generic clip strip because a lot of waste would arise and the clips would cause considerable risk of burr formation. In these two individual clamps, the object on which the invention is based was also not available, but instead, in order to save material, only individual clamps were to be produced from thin sheet metal, so that the object on which the invention was based was also not achieved.

To increase the locking force, especially for sausages with a large caliber and a high weight (diameter over about 60 mm and weight over about 1 kg), it is advisable to additionally provide that preferably in the outer edges of the band-shaped material in the area of the clip base and the legs a continuous groove is embossed in the area of the stiffening bead. This creates two ridges running along the outer edges, with a stronger upturn to the inside of the clip being expedient, which further increases the slip resistance and the locking force. The embossing also leads to a higher strength of the material and thus enables material savings.

In all of the comparisons, known longitudinal grooves were made on the inner surface of the clip, preferably in the region of the legs into which the inner bead does not extend, to increase the slip resistance compared to a closure clip made of smooth material.

The leg ends bent outwards should have the known U-shaped embossing at the bending point with the clip leg on the underside in order to ensure the associated advantages.

• Fig. 1 zeigt eine vom Klammerstreifen abgetrennte Verschlussklammer gemäss der Erfindung in Ansicht mit zwei Verbindungsbögen zwischen Klammerboden und Schenkeln.
• Fig. 2 zeigt eine vom Klammerstreifen abgetrennte Verschlussklammer in Ansicht mit einem gemeinsamen Radius.
• Fig. 3 zeigt drei zusammenhängende Verschlussklammern gemäss Fig. 1 mit in die Aussenkanten eingeprägter Rille.
• Fig. 4 zeigt eine Verschlussklammer gemäss Fig. 3 in verschlossenem Zustand.
• Fig. 5 zeigt einen Teilschnitt A-A durch die verschlossene Klammer gemäss Fig. 4.

The invention is described with reference to the following figures:

• Fig. 1 shows a closure clip separated from the clip strip according to the invention in view with two connecting bends between the clip base and legs.
• Fig. 2 shows a closure clip separated from the clip strip in view with a common radius.
• FIG. 3 shows three coherent locking clips according to FIG. 1 with a groove stamped into the outer edges.
• FIG. 4 shows a closure clip according to FIG. 3 in the closed state.
• FIG. 5 shows a partial section AA through the closed clip according to FIG. 4.

1 shows a closure clip with clip base 1, separated from the clip strip, with which the legs 2, 3 are connected via connecting bends 4, 5. The two connecting arches 4, 5 have radii R4 and R5 which are greater than the thickness of the band-shaped material of the clip. Extending over the clamp base 1 and the connecting bends 4, 5 is an inwardly directed connecting bead 6 which extends approximately to the transition of the connecting bends 4, 5 and thus at the center of the radii R4 and R5 and into the straight part of the legs 2 , 3 leak in the area 7, 8. The legs 2, 3 extend to the bending points of the leg ends 9, 10 which are bent outwards, with U-shaped impressions 11, 12 being attached to their underside.

FIG. 2 shows a closing clip separated from the clip strip, whereby — in contrast to FIG. 1 — the connecting bends 4, 5 form an arch with a common radius R with the clip base 1, so that a common center point 13 is created.

FIG. 3 shows a clip strip made of clips according to FIG. 1, wherein grooves 14, 15 (FIG. 5) running through in the outer edges of the band-shaped material in the area of the stiffening bead 6 are additionally embossed.

FIG. 4 shows a clip according to FIG. 3, which is closed around a packaging braid 16. It can be seen that the sausage braid 16 completely fills the closed clip in the area of the connecting sheets 4, 5, so that it is firmly pressed together over its entire surface.

5 shows a partial section AA through the butt seam 17, the sausage braid 16 and the clip base 1. The grooves 14, 15 stamped into the outside edge of the clip form the beads 20, 21 on the inside of the clip and the beads 22 on the outside. 23.

Claims (4)

1. A U-shaped closing clip made of strip material and for use with flexible tubes and bags, said clip consisting of a bottom (1) and two legs (2, 3), the leg ends (9, 10) being bent outwardly and constituting a connecting web, by which the clip is separably connected to other clips in a strip, the inside radius (R4, R5) of the bends (4, 5) connecting the bottom (1) to the legs (2, 3) being at least as large as the thickness of the strip material, characterized in that an approximately centrally disposed, preferably inwardly facing stiffening bead (6) is provided, which is restricted approximately to the region of the bottom (3) and the connecting bends (4, 5).

2. A U-shaped closing clip according to claim 1, characterized in that the inside radius (R4, R5) of the bends /4,5) connecting the crosspiece (1) to the legs (2, 3) is at least twice the thickness of the strip material.

3. A U-shaped closing clip according to claim 1 or 2, characterized in that the connecting bends (4, 5) and the bottom (1) constitute an arc having a common radius (R).

4. A U-shaped closing clip according to claim 1, 2 oe 3, characterized in that embossed continuous grooves (14, 15) are additionally formed in the outer edges of the strip material adjacent to the bottom (1) and the legs (2, 3), preferably adjacent to the stiffening bead (6).

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