DE8113934U1 - Tube with membrane closure - Google Patents

Description

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UNITED GERMAN METAL WORKS Ffm., May 6th, 1981

Aktiengesellschaft MLK / OKU Zeilweg

6000 Frankfurt / Main 50

Prov.No. 8727 BC

Tube with membrane closure

The innovation relates to a tube for sensitive filling goods with an integrally molded, the outlet opening until it is used for the first time and a membrane for piercing and excavating the membrane formed screw closure, which has a centrally arranged mandrel with screw thread and has an annular cutting edge.

For a number of sensitive filling goods, tubes are required whose outlet opening must be hermetically sealed and gas-tight until they are used for the first time. The screw caps usually used for tubes do not meet this requirement. It is therefore known to provide such tubes with an integrally molded membrane which must be pierced when used for the first time. In order not to make this piercing more difficult, the membrane ^{1 is made} as thin-walled as possible.

In the case of such membranes, it has proven to be disadvantageous that they tear open irregularly when they are pierced, that different sized lobes of the membrane are pressed into the interior of the tube and that the

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Opening the tube remaining parts of the membrane and pressing it out of the product and make it difficult to dispense when squeezing out. As particularly disadvantageous and In some respects it is also considered extremely dangerous that parts of the membrane can tear off the tube body, are squeezed out with the product and can cause significant disruptions when using the product. The use of such membranes in tubes intended for food or pharmaceutical ointments, for example is therefore not possible.

To overcome the disadvantages mentioned it has already been proposed to use the screw cap for tubes Form piercing and excavation of the membrane by a centrally located mandrel with screw thread and an annular cutting edge was provided. Such screw closures have one for the usual reclosure the tube with certain cap-shaped part inserted soft seal, with the intended for piercing and lifting the membrane parts on the back this cap are arranged and can be used in the reverse position of the screw cap. It has However, it has been found that even with these devices that are integrally formed with the tube body, the The outlet opening cannot be properly pierced and sealed until the first use are to be excavated. Individual pieces of such screw caps made for experimental purposes were sufficient The implementation of these results in series production was difficult and unsatisfactory, because here the possible manufacturing tolerances for both the membrane and the screw caps are not satisfactory Reproducibility of the results achieved in the individual experiment showed.

It was not possible to remove the membrane properly and without residues remaining in the tube.

The object of the innovation is therefore to provide a membrane for a tube of the type mentioned at the beginning create that can be punctured properly with the specified screw cap and excavated without leaving any residue. f

A membrane is proposed to solve this problem "",. iminde st ens, double. . . § ■

gen, the exwav,. the board is designed like the f

cylindrical tube wall and a central conical recess and an annular weakening groove having. The thickness of the membrane is in the area of the central conical recess and the annular The weakening groove is preferably reduced to about half the non-weakened membrane thickness.

It was recognized that the - usually proportionate thin membranes do not meet the requirements, because they even with a relatively elaborately designed screw cap cannot be removed without leaving any residue, since they tear in an uncontrolled manner the mandrel provided with screw thread does not find sufficient hold and on the outer edge also with a precise one The annular cutting edge cannot be reliably separated from the tube body = these unsatisfactory results have been found in both plastic and aluminum tubes. However, the membrane will accordingly the proposed innovation made relatively thick-walled and with a central cone-shaped Well provided and an annular weakening groove, so it can with the specified screw cap be properly pierced and excavated completely.

It is essential that the membrane has sufficient inherent rigidity. This is achieved when they are around

doubled
the corner of the cylindrical tube wall and if its thickness is reduced to about half in the intended places. With this stipulation, perfect results could be achieved with both aluminum and plastic tubes.

In Figure 1, the upper part of a tube is shown in cross section. With 1 is the outside with a screw thread labeled tube neck. The membrane 2, which has been thickened according to the invention compared to the membranes customary up to now, has a central conical recess 4 and an annular weakening groove 3.

In Figure 2, the associated, known screw cap is shown, with 5 in the normal position of use usable cap and 6 denotes the inserted soft seal. In the reverse position of use the centrally arranged mandrel 7 with screw thread is used to pierce the membrane and the annular Cut 8 to sever the membrane along a line along the exit opening. When unscrewing With this seal, the membrane is first pierced centrally and then cut through in a ring. When unscrewing of the closure, the severed membrane remains hanging on the screw thread of the dome 7 and is perfect excavated.

- 5 protection claims

Claims (2)

PROTECTION CLAIMS 1. Tube for sensitive filling goods with a one-piece molded membrane that closes the outlet opening until first use and a screw cap designed to pierce and lift out the membrane, which has a centrally arranged mandrel with screw thread and an annular cutting edge, characterized in that the membrane ( 2) about *)> is made as thick as the cylindrical tube wall (5), and that it has a central conical recess (4) and an annular weakening groove (3) is provided. · *) At least twice 2. Tube according to claim 1, characterized in that the thickness of the membrane (2) in the region of the conical recess (4) and the annular weakening groove (3) is reduced to about half the non-weakened membrane thickness.