EP0733013B1 - Twist-off closure for containers - Google Patents

Abstract

PCT No. PCT/DE94/01280 Sec. 371 Date Apr. 5, 1996 Sec. 102(e) Date Apr. 5, 1996 PCT Filed Oct. 31, 1994 PCT Pub. No. WO95/15892 PCT Pub. Date Jun. 15, 1995A twist-off closure is disclosed for all kinds of containers having a head and a closure cap. The container head has at its top end a sealing lip shaped as a circumferential bead. A steep, multiple-start thread is located below the sealing lip. A fin is arranged between each winding of the steep thread and the container shoulder. The closure cap has a corresponding inner thread that co-operates in the closed state with the fins of the container head causing the closure cap to be clamped, so as to prevent the container from being unintentionally opened by itself. In the closed state, the first part of the windings of the thread of the closure cap engage the fins of the container head, and this is clearly perceived as a pressure point when twisting the cap by hand. All that is required to open and close the closure cap is to twist it through a half turn. The cylindrical inner part of the closure cap forms a movable seal together with the circumferential lip of the container head, preventing the contents of the container from flowing out, so that the tightness of the container is ensured even when the closure cap is only negligently screwed (for example only up to the pressure point). In addition, once the pressure point is reached, the closure cap is reliably prevented from opening by itself.

Description

The invention relates to a rotary clamp closure, also called a fractal closure, according to the preamble of claim 1. It is provided for a container to be closed with a cap of any dimension and design, which contains an integrated container head with an opening for removing liquid, pasty or pourable materials.

There are plugs, crown caps and caps for closing containers that are commonly used in the household, the latter being designed as classic screw-type closures, preferably with an internal thread and closed bottom or lid, or in a more recent form with an integrated hinged lid, so-called one-hand hinged closures. In the case of the classic screw-type closures, more than half a turn is required for opening, but disadvantageously for the user usually an entire turn and more.

Containers that are used with the opening inclined downwards, such as toothpaste tubes, can show undesirable premature leakage of the contents. Folding closures tend to open themselves, especially if the contents of the container are smeared in the area of the outlet opening, which often occurs with pasty products. The hygienic tightness of the snap lock is not always guaranteed. To the disadvantages described to counter this, some technical solutions are known.

In DE 37 42 692 A1, DE 40 29 467 A1, DE 29 13 883 A1 and DE 32 47 353 A1 closures are described, some of which are already fully open after a 1/4 turn and an emotionally noticeable snapping in and out with the corresponding Ensure rotational movement. For this purpose, circumferential beads, snap-in grooves and cams or tongues are used. The threads are multi-start with lead angles between 30 ° and 45 °.

GB 21 81 721 A describes a closure which has a web on the container head, but uses this web as a stop for the purpose of the defined alignment between the closure cap and the container.

From GB 2 203 729 a generic closure is known, with thread sections distributed around the neck of the vessel, which correspond to analog thread sections of the closure cap. Each thread section also has a web. Thread sections and webs are designed so that parts of the thread sections can snap behind the webs during the closing process.

The subject of US Pat. No. 5,009,323 is a closure with a standardized threaded cap, on the edge of which a strip made of frangible fabric is attached, which is intended to protect against misuse or unauthorized opening.
The structure and functional mechanism of this fresh seal is described below.
There is a sealing lip on the container head of the closure, which is received by the cylindrical part of the cap when the closure cap is unscrewed.

A disadvantage of the technical solutions described is that the tightness of the closure against leakage of the container contents when the container is closed negligently by rotating the cap is not automatically ensured only up to the pressure point. Rather, in the known technical solutions, the cap must always be tightened as far as it will go, that is, beyond the pressure point.

• sich mit einer kurzen Drehbewegung (unter 180° Drehwinkel) öffnen und schließen läßt,
• im geschlossenen Zustand gegen ungewolltes selbständiges Öffnen gesichert ist (Klemmen) und
• der selbst bei nachlässigem Verschließen (nicht bis zum Anschlag festgedreht) gegen Auslaufen des Füllgutes dicht ist.

The invention is therefore based on the object of creating a generic twist-lock closure which

• can be opened and closed with a short rotary movement (at an angle of rotation of 180 °),
• is secured against unintentional opening in the closed state (terminals) and
• which prevents the filling material from leaking even if it is closed carelessly (not tightened as far as it will go) is tight.

This object is achieved by the characterizing features of the main claim. Advantageous further developments are the subject of the subclaims.

The twist-lock closure according to the invention is characterized in that the container head contains in the upper region a sealing lip designed as a circumferential bead, a multi-start helical thread and an identical number of webs with the number of threads. Distributed over the circumference in the lower region of the container head are a plurality of thread sections which form a steep thread and are shifted parallel to one another and form the steep thread.

The vertical webs, which run parallel to the longitudinal axis of the container, are each arranged with beveled flanks approximately in the middle with cross-sectional dimensions that are similar in comparison to the formation of the thread and adjoining the thread sections.

The threads of the closure cap are designed analogously to the container head, above the steep thread consisting of thread sections, a cylindrical part is provided for receiving the sealing lips.

Sealing lip and steep thread of the container head formed with vertical webs, in conjunction with the corresponding steep thread of the closure cap, guarantee security against leakage of the container contents at half a turn of the closure cap against the noticeable pressure point.

In this position of the cap, a press clamping begins the first part of the threads of the closure cap with the webs of the container head. When the cap is turned further beyond the clearly noticeable pressure point, the clamping effect is achieved. If you open the cap, the effects described occur in reverse order. The cap remains clamped up to a rotation angle of 30 °, so it is secured against unintentional, independent opening. Up to a rotation angle of 80 °, the circumferential bead, which is designed as a sealing lip in the container head, acts as a seal against unwanted leakage of the container contents. Only when the cap is turned further than 80 ° is it loosened and can be removed after half a turn.

This ensures handling during the removal of the filling material and the reclosing of the container by means of a rotary movement that is very familiar to the consumer, whereby on the one hand, due to the long clamping phase of 30 ° rotation angle, a high level of security against premature undesired filling material leakage, and on the other hand, due to the fact that the closure cap can be removed after only half a turn rapid filling removal is made possible. In this way, the cap can be removed from the container without changing fingers, and can also be replaced and closed.

After reaching the first pressure point, which results from the entry of the sealing lip formed as a circumferential bead on the container head into the cylindrical part of the closure cap (approx. 80 ° rotation angle before complete closure), the container is already secured against leakage. After exceeding the second pressure point, which results from the engagement of the first part of the steep threads of the closure cap in the webs of the container head results (approx. 30 ° angle of rotation before it is completely closed), the container is completely secured against unintentional opening, eg in the event of vibration.

Fig. 1

vereinfacht einen Schnitt durch Behälterkopf und Standverschlußkappe,

Fig. 2

ein vergrößertes Detail der erfindungsgemäßen Merkmale Steilgewinde, Dichtlippe am Behälterkopf und Standverschlußkappe,

Fig. 3

vereinfacht einen Schnitt durch Behälterkopf und Kegelhutverschlußkappe,

Fig. 4

ein vergrößertes Detail der erfindungsgemäßen Merkmale Steilgewinde, Dichtlippe am Behälterkopf und Kegelhutverschlußkappe.

The subject matter of the invention is explained in more detail below on the basis of exemplary embodiments. In the accompanying drawings:

Fig. 1

simplifies a cut through the container head and stand cap,

Fig. 2

an enlarged detail of the features according to the invention steep thread, sealing lip on the container head and stand cap,

Fig. 3

simplifies a cut through the container head and conical cap,

Fig. 4

an enlarged detail of the features steep thread, sealing lip on the container head and conical hat cap.

In the illustrated embodiment according to FIGS. 1 and 2, container head 4 and closure cap 5 are made of plastic, for example polyethylene. The steep thread 1 of the container head 4 has three threads and has an incline of 15 °. When the cap 5 is closed, the first pressure point is reached when the sealing lip 6 of the container head 4 is immersed in the cylindrical part 7 of the cap 5. From this position of the closure cap 5, the sealing lip 6, which is designed as a circumferential bead, seals flush with the cylindrical part 7 of the closure cap 5 so that the container contents can no longer escape.

When turning further, the first part of the steep thread 3 of the closure cap 5 slides with its tip onto the webs 2 of the container head 4, which can be felt as a second pressure point. This pressure clamping effect is retained until it is fully screwed on (stop).

The webs 2 themselves are connected to the threads of the container head 4 in such a way that there is a small bevel 8 between the webs 2 and the thread tip, which makes it easier for the latter to run onto the webs 2, so that no excessive torque is required when screwing on the closure cap 5 .

If you open the cap, the effects described occur in reverse order. Up to a rotation angle of 30 °, the closure cap 5 remains clamped, so it is secured against unwanted, independent opening. Up to a rotation angle of 80 °, the circumferential bead 6 designed as a sealing lip in the container head 4 acts as a displaceable seal against unwanted leakage of the container contents. Only when the cap 5 is turned further beyond 80 ° is it loosened and can be removed from the container head 4 after half a turn. This ensures handling when removing the filling material and reclosing the container by means of a rotary movement that is very familiar to the consumer, whereby on the one hand the long clamping phase of 30 ° rotation angle ensures a high level of security against premature undesired filling material leakage and on the other hand the fact that the closure cap can be removed after only half a turn rapid filling removal is made possible. In this way, the cap can be removed from the container without changing fingers, and can also be replaced and closed.

Overall, the effort and time required to open and close the container for the consumer is considerably less than with normal rotary closures, which allows user-friendly handling.

3 and 4, the features according to the invention for a conical hat closure cap are shown, the design and mode of operation of which are completely identical to the above description.

3 and 4 thus represent only external design examples of possible caps, without this being a separate claim to the invention.

Claims (5)

1. A twist-off closure, also called fractal closure, for any kind of container, comprising a closure cap (5) and a container head (4), the container head further having fins (2), the lower portion of the container head (4) having a steep, multiple-start thread (1) which consists of thread segments, and the thread segments (1) of the container head (4) having vertical fins (2) with similar cross section dimensions
   wherein

   a) the steep thread (1) has a pitch of less than 30°

   b) the vertical fins (2) are arranged approximately centreline in the thread segments (1)

   c) a sealing lip (6) shaped as a circumferential bead is provided in the upper portion of the container head (4) and is arranged, such that the sealing lip (6) and closure cap (5) engage before the thread (3) of the cap (5) begins to get on the vertical fins (2), and

   d) the threads (3) of the closure cap (5) are formed and arranged in the same way as the threads of the steep thread (1) of the container head (4) with a cylindrical portion (7) provided above the thread segments (3) to receive the sealing lip (6).
2. Twist-off closure of Claim 1,
   wherein the steep threads (1) and (3) of the container head (4) and closure cap (5) comprise three thread sections displaced parallel in relation to each other.
3. Twist-off closure of Claim 1 or 2,
   wherein the steep threads (1) and (3) have a pitch of 15°, such that it is possible to open and close the container with a half turn without the need to reposition the hand.
4. Twist-off closure of any of the Claims 1 to 3,
   wherein the circumferential bead acting as a sealing lip (6) is arranged such that it provides a tight seal with the cylindrical portion (7) of the closure cap (5) even in the event that the closure cap (5) is screwed on only barely past the first slight pressure point which occurs when the sealing lip (6) begins to engage the cylindrical portion (7) of the closure cap (5).
5. Twist-off closure of any of the Claims 1 to 4,
   wherein the vertical fins (2) oil the container head (4) have chamfers (8) which make getting on of the appropriate thread crest of the closure cap (5) easier.

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