EP1050477A1 - Screwcap - Google Patents

Abstract

The screw cap (1) is made of plastic and has an internal thread (2). The outer surface (6) of the side wall (7) is built ont the internal thread after the initial manufacture. The wall thickness of the cap is constant over the entire height of the thread. T surface may be rippled or ribbed at the transition from the cap side wall to the cap top (8).

Description

The invention relates to a cup-shaped screw cap made of plastic with internal thread.

Known screw caps made of plastic have on the inner peripheral surface of its side wall an internal thread, the with a provided on a container to be closed Male thread is engageable, and a smooth or also ribbed or corrugated outer surface.

The corrugation or the ribbing of the outer surface serves to a better contact surface when opening the screw cap to offer with more hold. To do this, they run vertically on the lateral surface and are only slightly pronounced. The Internal thread forms inward thickening of the Lock side wall.

When manufacturing plastic screw caps, which are preferably injection molding or after Die casting (compression molding principle) is done one always strives to save material in order to reduce manufacturing and later also transportation costs.

The object of the invention is a screw cap of the above Way of creating for the less plastic material is needed without losing its stability and functionality is affected.

This is achieved according to the invention in that the outer Lateral surface of the side wall of the screw cap Internal thread is reproduced its inner peripheral surface and the wall thickness of the screw cap over the entire The height of the thread is constant.

Since the thread of the screw cap is no more than an inward, beaded thickening of the closure side wall appears, but this overall wave-like follows the screw thread, it becomes an even one Wall thickness formed what is called a plastic solution can be. There is a considerable saving of material, and this immediately has an increase in production and energy saving in manufacturing Episode; the proportion of dye required is also reduced in in cases where the screw cap is colored it is asked for. Overall, the manufacturing costs significantly reduced. Further advantages result from the Material savings e.g. during transportation in large quantities the lower weight and also when recycling, because it consequently, less material has to be recycled become. So is ecological in general served.

Another advantage is that the replica of the thread on the outer surface of the screw cap externally referred to the property as a screw cap , so there is a recognition effect, which in further use, e.g. useful in filling facilities is.

Due to its overall undulating course, the closure side wall also has good strength, stability and resilience, so that the functional safety of the screw closure is in no way impaired or reduced by the material savings achieved.
The thread replica on the lateral surface already offers a good and in itself sufficient contact surface when opening the closure. If desired, this can be further improved by additionally having a corrugation or ribbing in the area of the transition from the closure wall to the closure base and possibly also in the area of the open edge or the transition to a guarantee ring attached via predetermined breaking points.

Fig. 1

zeigt die Seitenansicht eines auf eine Behälteröffnung aufgeschraubten erfindungsgemäßen Schraubverschlusses und

Fig. 2

zeigt denselben Schraubverschluß, wobei ein Teil der Verschluß-Seitenwand geschnitten bzw. weggebrochen ist.

The invention is described below with reference to the accompanying drawings.

Fig. 1

shows the side view of a screw cap according to the invention screwed onto a container opening and

Fig. 2

shows the same screw closure, with a part of the closure side wall cut or broken away.

The cup-shaped screw cap 1 has in a known manner on the inner peripheral surface of its substantially cylindrical Side wall 7 an internal thread 2 (see Fig. 2) and is on the one with an appropriate external thread screwed provided opening of a container 3. With the open edge 10 of the screw cap 1 is over web-like Breakage points 4 connected a guarantee ring 5, which at Closing the container 2 is applied so that it an outward bulge on the outer wall of the Reaches under the container opening. As is known, the first time Open the screw cap 1 of the guarantee ring 5 separated from the screw closure 1 at the predetermined breaking points 4, indicating that the container 3 has been opened.

The lateral surface 6 of the closure side wall 7 follows this new screw cap 1 exactly the internal thread 2 in the inner circumferential surface and thus reproduces the thread outside towards; the outer surface 6 thus appears as with a Provided with external thread. As can be seen from Fig. 2, that forms Internal thread 2 no longer as with known screw caps inward thickening of the closure side wall 7, but this follows the course in a wave shape of the internal thread 2 and the thickness of the closure side wall 7 remains the same over the entire height of the thread. Because it there is no thickening of the closure side wall 7, one considerable material savings achieved, which increases production and saves energy and generally reduces costs the manufacture of the screw cap 1 affects. On the other hand receives the closure side wall 7 by its wave-like Sufficient stability and strength, so that the wall thickness does not have to be increased overall. Likewise, the outer surface 6 offers through its wavy A good contact surface when opening the screw cap 1. This will be improved if in the transition area the closure side wall 7 to the closure bottom 8 and additionally in the area of the open edge 10, on which the Guarantee ring 5 attached, a corrugation or ribbing 9 provided is.

Reference symbol list :

1

Screw cap

2nd

inner thread

3rd

container

4th

Predetermined breaking points

5

Guarantee ring

6

Lateral surface

7

Closure side wall

8th

Closure bottom

9

Corrugation, ribbing

10th

edge

Claims (3)

Cup-shaped screw cap made of plastic with internal thread,
characterized,
that the outer lateral surface (6) of the side wall (7) of the screw cap (1) is modeled on the internal thread (2) of its inner peripheral surface and the wall thickness of the screw cap (1) is constant over the entire height of the thread. Screw closure according to claim 1, characterized in that that on the lateral surface (6) in the region of the transition from the Locking side wall (7) to the lock bottom (8) a corrugation or ribbing (9) is provided. Screw closure according to claim 1 or 2, characterized in that in the area of the open edge (10) or Transition to one hanging over predetermined breaking points (4) Guarantee ring (5) of the closure side wall (7) a corrugation or ribbing (9) is provided.

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