EP0583576A1 - Telescopic closure - Google Patents

Abstract

The present invention relates to a container closure having a telescopic tube (1) which can be extended in a telescopic manner from a container neck (2), and having a closure cap (3) which can be screwed onto the container neck (2). In order to provide a container closure having the features mentioned at the beginning, which is easier to handle than the known closures, it is proposed according to the invention that the telescopic tube (1) has at its upper end a radial widening (5) whose outside diameter is greater than the inside diameter of the upper edge (4) of the container neck (2). <IMAGE>

Description

The present invention relates to a container closure with a tube telescopically extendable from a container neck and a closure cap which can be screwed onto the container neck. Such telescopic closures have long been known, for example, for containers for motor oil. Containers in general and in particular plastic canisters for motor oil should be as space-saving as possible, easy to store and transport. This means that the pouring opening of a container or oil canister is often only on a short container neck Form of a pipe socket with an external thread is provided, on which a closure cap can be screwed. From such a full canister, it is almost impossible to pour the oil in loss-free filling openings, such as, for example, the oil filling opening of an engine, so that the surroundings of the filling opening often become contaminated. The relevant telescopic closures are intended to counteract this by providing an extended pouring tube which can be brought in a more favorable position and closer to a corresponding filler opening in order to avoid spilling the oil.

It goes without saying that oil cans are only mentioned here as an example and that avoiding the inadvertent spillage of liquid is a problem that occurs in a wide variety of areas, especially when dealing with other environmentally hazardous and / or chemically aggressive or hazardous liquids.

Various variants of telescopic closures are known, which are not only designed as pure extensions of the neck of the container, but also have special configurations which have a ventilation function so that the liquid can be poured out without bubbles and bumps, and which also provide ventilation options when the container is being filled , even if the liquid level in the container has already reached the lower edge of the telescopic closure. These include, in particular, the double-walled telescopic closures, some of which have annular ventilation channels, some of which are only provided on one side.

In order to prevent the telescopic closure from slipping completely into the container, latching cams or the like are generally provided on the outside of the telescopic tube. In the case of a ring-shaped additional outer tube for the formation of ventilation channels, its lower edge can also be used as a stop surface in order to prevent the telescopic tube from being pushed completely into the interior of the container through the neck of the container.

Similarly, pull-out stops in the form of projections, cams or flanges are generally provided at the lower end of the telescopic tube, which are intended to prevent the telescopic tube from being completely pulled out of the container and to define the end position of the extended tube by its stop.

In the closed state of such a telescopic closure, the telescopic tube is fully inserted into the container neck, so that a screwed-on closure cap seals with the can engage the top of the container. In addition, an axially extending, cylindrical extension is provided on the inside of the cap base, the outside diameter of which after the closure cap has been produced is somewhat larger than the inside diameter of the telescopic tube, so that this cylindrical approach slides into the telescopic tube when the closure is screwed on and in firm frictional engagement with the inner wall of the telescopic tube. When the cap is unscrewed, the telescopic tube is then taken along by this frictional engagement and pulled out of the container neck by lifting the cap until the pull-out catches strike the lower region of the container neck and the cylindrical extension of the cap then slides out of the telescopic tube.

A disadvantage of the known telescopic closures is, among other things, that they generally end up as a smoothly cut tube, which does not have particularly good pouring properties, so that after pouring out liquid, drops often drip from the free edge of the telescopic tube or on the outside and also on the outside thereof run down the neck of the container. The other handling of such telescopic locks is sometimes difficult if e.g. the cylindrical attachment detaches from the inner surface of the telescopic tube at an early stage or the telescopic tube has been pushed back into the neck of the container after being pulled out. The pulling out of the telescopic tube again without screwing the cap back on is then difficult and often only possible with soiling of the fingers or with the use of additional auxiliary objects.

The sealing of such closures also occasionally presents problems, since the telescopic tube itself, especially if it has ventilation channels, does not perform a sealing function and, above all, to facilitate removal from the container, it is generally arranged with a clearance fit in the container neck.

However, both the container neck itself and the screw cap of the closure generally consist of a harder plastic, whereby the known manufacturing processes and the corresponding plastic objects always have manufacturing tolerances that do not always guarantee a tight engagement between the closure cap and the container neck. For this reason, either sealing rings are inserted between the container neck and the cap, or sealing compounds are injected into the cap.

Repeated use of the closure does not always guarantee its tightness.

Compared to this prior art, the present invention has for its object to provide a container closure with the features mentioned above, which is easier to handle than the known closures.

This object is achieved in that the telescopic tube has a radial extension in its upper end region, the outer diameter of which is larger than the inner diameter of the upper edge of the container neck.

This configuration means that the telescopic tube can not be fully inserted into the container neck, but with its radial expansion rests more or less on the edge of the container neck. This has several advantages. On the one hand, the telescopic tube protruding from the neck of the container with such an extension can be easily grasped from the outside and pulled out of the neck of the container. The radial extension can also be designed so that it has the shape of a pouring lip, from which the liquid easily detaches when pouring and from which even the last drops more easily dissolve when the pouring is finished, so that the liquid is no longer on the outside of the Telescopic tube and on the neck of the container runs down and contaminates the container. Furthermore, the radial expansion can be used expediently to improve the sealing of the closure, in particular when used repeatedly, as will be shown in more detail below. In the simplest case, the radial extension itself acts as a sealing ring between the container neck and the closure cap.

Finally, the radial extension can also be used for the engagement with the closure cap, so that the telescopic tube is not or not only entrained by the engagement of a cylindrical extension of the closure cap in the telescopic tube when unscrewing and lifting the closure cap, but also by the engagement of the radial Extension with corresponding protrusions or the like inside the cap.

In the preferred embodiment of the invention, the radial extension has a flange-like circumferential collar, the outer diameter of which is preferably also even larger than that of a retaining bead circumferential on the essentially cylindrical inner wall of the closure cap. In the closed state of the closure, this flange-like circumferential collar engages behind the above-mentioned retaining bead and is carried along by the retaining bead when unscrewing and lifting the closure cap until the pull-out catches at the lower end of the telescopic tube prevent the latter from being pulled out further, so that the flange-like circumferential collar over the retaining bead the cap slides away and is released.

Of course, the retaining bead can also have interruptions without losing its function. The retaining bead preferably has a clear distance from the bottom of the closure cap, which corresponds approximately to the thickness of the flange-like circumferential collar of the telescopic tube. The bead preferably has an approximately triangular cross section, that is to say is formed by two intersecting, oppositely directed conical surfaces.

In the preferred embodiment of the invention it is provided that the radial extension has an at least partially lower contact surface running in a radial plane. This support surface is provided for engagement with the upper edge of the container neck, the closure cap pressing from above onto the edge or the radial extension of the telescopic tube and thus also pressing the support surface onto the edge of the container neck. The sealing function can already be achieved by the pressure of the bottom of the closure cap on the upper edge or the radial extension of the telescopic tube, and by the firm support of the lower contact surface of the radial extension on the edge of the container neck.

However, the seal between the container neck and the telescopic tube, more precisely the outside of the telescopic tube, can also be achieved by providing conical sealing surfaces which engage with one another on the container neck below the edge of the container and on the telescopic tube below the radial extension, the contact surface of the radial expansion on the upper edge of the container neck only limits the insertion of the telescopic tube into the container neck and thus also determines the maximum engagement force between the underlying conical sealing surfaces. The angle of inclination of the conical sealing surfaces with respect to the axis of the telescopic tube should be relatively small in order to achieve a sufficient surface pressure, but not so small that this surface pressure opposes the extension of the telescopic tube with a noticeable frictional resistance. The cone angle with respect to the axis of the telescopic tube should therefore be at least 5 °, better still more than 10 ° and preferably about 15 °, it being expedient if this angle does not exceed a value of 30 °, since otherwise the sealing effect between the conical surfaces compared to a simple flange seal is not so significantly improved.

In the simplest embodiment, however, the telescopic tube is only provided at its upper end with a radially outwardly extending flange, which engages behind the retaining bead of the closure cap with its outer edge, while the lower bearing surface of the flange, which runs essentially in a radial plane, on the edge of the flange Container neck rests. In this embodiment, the flange attached to the upper end of the telescopic tube has the function of a normal sealing ring between the bottom of the closure cap and the edge of the container neck. It goes without saying that in the region of this flange the bottom of the closure cap and also the container rim can be dimensioned and designed in such a way that an essentially linear pressure occurs along the entire circumference, since such linear pressures ensure a reliable seal.

However, an embodiment of the invention is preferred in which the holding function of the flange and its sealing function with respect to the screw cap is separated from the seal between the outside of the telescopic tube and the container neck. The latter seal is preferably achieved by the conical design of sealing surfaces, the upper inner edge of the edge of the container neck being chamfered to produce a conical surface, while the telescopic tube below the radial enlargement exceeding the inner diameter of the container neck additionally has a conical enlargement, which also includes the conical inner surface of the neck of the container resulting from the bevel can engage. In this case, a radially extending support surface can be provided on a projection above the conical extension and immediately after it, which defines a stop on the edge of the container neck and which is independent of the flange arranged further up at the end of the telescopic tube. The inner edge at the upper end of the telescopic tube can be beveled or the upper end of the telescopic tube can be slightly tapered so that a corresponding cylindrical projection on the bottom of the sealing cap can engage in the telescopic tube so that the seal between the sealing cap and the telescopic tube can also pass through Engagement of two conical surfaces takes place, which generates a relatively high surface pressure force when the conical surfaces are correspondingly steep and with a given axial force by screwing the closure cap.

Irrespective of this, the interior of the telescopic tube could also be sealed by a tear-open sealing membrane, at least before the first use.

In the preferred embodiment, the material of the telescopic tube is softer than the material of the closure cap and also softer than the material of the container neck. A low-density polyethylene is preferred for the telescopic tube and a high-density polyethylene for the closure cap. The softer material of the telescopic tube makes it easier to ensure the seal between the telescopic tube and the closure and also between the telescopic tube and the neck of the container.

Furthermore, in the preferred embodiment of the invention, the telescopic tube has latching cams in the region of its lower half, which prevent the telescopic tube from being inadvertently inserted after the telescopic tube has been pulled out of the container neck, since they engage with the upper edge of the container neck and only pushes it back through Applying a certain force to oppose resistable resistance. In the preferred embodiment of the invention, the distance between the locking cams and the lower end of the telescopic tube is approximately 1/3 of the total length of the telescopic tube.

It is also expedient if the telescopic tube is more easily deformable in the area of these latching cams than in its other areas, in order not to have to exert excessive deformation forces when the telescopic tube is pulled out and possibly also when it is inserted again.

The telescopic tube in the area of these projections expediently simply has a somewhat smaller wall thickness than in the other areas. At a distance below the locking cams, pull-out locks in the form of radially extending projections or in the form of a circumferential flange are also provided, which come into engagement with the lower edge of the container opening or the container neck when the telescopic tube is pulled out and thus limit the extraction of the tube.

Finally, such an embodiment of the invention is preferred, in which the flow cross section is tapered at the inner end of the telescopic tube, wherein ventilation openings can also be provided in the end section in the wall of the telescopic tube. These measures ensure that the emerging liquid jet does not fill the entire cross section of the telescopic tube, so that air can still pass the liquid and enter the interior of the container through the corresponding ventilation openings.

The tapering of the flow cross-section is achieved, for example, by inwardly projecting tabs arranged at the inner end of the telescopic tube, which are preferably arranged approximately along an imaginary conical surface. Slots that remain free between the tabs can serve as ventilation openings. However, ventilation openings are preferably provided in the cylindrical wall of the telescopic tube above the attachment of the tabs

Figur 1

einen geschlossenen Teleskoprohrverschluß an einem Behälter,

Figur 2

denselben Verschluß mit ausgezogenem Teleskoprohr, jedoch noch mit aufgesetzter Verschlußkappe,

Figur 3

das an dem Behälter ausgezogene Teleskoprohr ohne Verschlußkappe,

Figur 4

die aus der Verschlußkappe und dem Teleskoprohr bestehende Verschlußeinheit, wie sie als von dem Behälter getrenntes Teil lieferbar ist und

Figur 5

schematisch einen vergrößerten Ausschnitt des Dichtungsbereiches aus Figur 1.

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

Figure 1

a closed telescopic tube closure on a container,

Figure 2

the same closure with the telescopic tube extended, but still with the closure cap on,

Figure 3

the telescopic tube extended on the container without a cap,

Figure 4

the closure unit consisting of the closure cap and the telescopic tube, as is available as a part separate from the container, and

Figure 5

schematically shows an enlarged section of the sealing area from Figure 1.

Unless expressly differentiated, the following description refers simultaneously to all FIGS. 1 to 5, which only show the same embodiment in different positions.

As already mentioned, FIG. 1 shows the telescopic closure in a completely closed state before it is opened for the first time. The container 8 has a container neck 2 which is provided with an external thread 28 (see FIG. 2). A closure cap 3 is screwed onto the container neck 2 after a telescopic tube 1 has been inserted into the container neck 2. The telescopic tube 1 can be pushed in with the closure cap 3 in place in a state shown in FIG. 4, for example.

The insertion of the telescopic tube 1 is facilitated by the conical lower end section of the telescopic tube 1 and in particular by the obliquely rising flanks of the pull-out lock 20, which yield accordingly when inserted through the container neck 2.

The locking cams 21 are provided in the lower half of the telescopic tube in an area 30 of thinner wall thickness of the telescopic tube 1, so that the locking cams 21 can be pressed inward relatively easily in order to be able to move them past the upper edge 4 of the container neck 2.

As can be seen particularly well in FIG. 5, the telescopic tube 1 has a radial extension 5 at its upper end. In the embodiment shown, this radial extension 5 consists of an end flange 6 and a projection 7 which is nose-shaped in cross section. The nose-shaped projection 7 forms at its lower end an essentially flat, annular support or stop surface 10, which rests on the upper edge 4 or on the edge surface 4 of the container neck 2 in the closed state of the closure. This state is achieved by screwing the closure cap 3 onto the container neck 2 with the telescopic tube 1 used. The top 12 of the closure cap 3 presses from above onto the flange part 6 of the telescopic tube and indirectly also presses the lower surface 10 of the nose-shaped projection 7 on the edge surface 4 of the container neck 2. Before this end state is reached, however, the conical surfaces 16 on the outside of the conical extension 9 of the telescopic tube 1 already engage with the conical surface 15 on the upper inside of the container neck 2, whereby the latter is designed as a bevel of the upper inner edge of the container neck 2. The angle α of the conical surfaces 15, 16 with respect to the axis of the telescopic tube 1 is preferably the same, however, for example, the surface 15 can also run steeper if an approximately linear pressure along the transition from the conical section 9 of the telescopic tube to a steeper, approximately prefers vertical section.

So while the sealing of the telescopic tube 1 takes place in the closed closure essentially between the surfaces 15, 16, possibly also between the surfaces 4, 10, there is a seal between the closure cap 3 and the telescopic tube 1 essentially on the inside of the telescopic tube in the upper End area instead of where the approximately cylindrical projection 11 is in close engagement with the inner surface of the telescopic tube 1. Here too, the inner end surface 13 of the telescopic tube 1 and the outer peripheral surface 14 of the extension 12 can be provided with a slight cone angle in order to achieve a higher surface pressure, so that when the closure cap 3 is screwed onto the container neck 2, a certain wedge effect between the conical surfaces 13, 14 achieved and thus the contact pressure essential for the seal is achieved.

In contrast to the prior art, however, the telescopic tube 1 when unscrewing and z. B. even before the first screwing not by the frictional engagement of the surfaces 13, 14 on the cap 3, but rather by the flange 6, which engages behind the circumferential bead 17 of the cap 3. However, the cylindrical shoulder 11 contributes to a secure hold of the flange 6 on the closure cap 3 by the inner support of the flange part 6. The force which is required to pull the closure cap 3 upward from the flange 6 depends both on the (radial) height or thickness of the bead 17 and on the angle of the conical surface 31 which delimits the bead 17 at the top. Pushing the closure cap 3 onto the upper end of the telescopic tube 1 is facilitated by the relatively steep course of the conical surface 32, on which the flange 6 slides with its outer edge upwards over the bead 17 when the closure cap is pushed onto the telescopic tube 1.

The clear distance between the bottom 12 of the closure cap and the bead 17 or the conical surface 31 delimiting the bead 17 corresponds precisely to the thickness of the flange part 6. When screwing the closure cap 3 already shown in FIG. 4 with an inserted telescopic tube 1 onto a container neck 2, the conical surfaces 15, 16 come into sealing engagement with one another, the surface 10 of the projection 7 acts as a limit stop which is at the upper edge 4 of the Container neck 2 strikes and thus fixes the contact pressure of the sealing surfaces 15, 16 to each other quite well or limits it upwards.

For example, three pieces of the lower locking cams 21 are distributed over the circumference of the telescopic tube 1, so that only one locking cam can be seen on one side in the axial sectional views of the accompanying figures. The lower edge of these locking cams 21 has a clear distance from the upper edge of the pull-out lock 20, which is designed as a flange and corresponds approximately to the axial length of the container neck 2.

As can be clearly seen in FIGS. 2 and 3, the axial length of the container neck 2 is defined without a stepped offset at the lower end of the container neck 2. This cranked lower section of the container neck has an outward projection 26 which retains a securing and guarantee ring 25 on the container neck 2 when the screw cap 3 is unscrewed and the tearable connecting tabs between the guarantee ring 25 and the screw cap 3 are broken open.

In the extended state of the telescopic tube 1 shown in FIGS. 2 and 3, there is only a short end section of the telescopic tube 1 with the ventilation openings 23 and the tabs 22 constricting the flow cross section in the interior of the container 8. In this extended state there is also a certain amount of sealing between the outside of the telescopic tube 1 and the container neck 2, namely along the conical surface 24 above the pull-out lock 20, this conical surface coming into sealing engagement with the rounded inner edge at the lower edge of the container neck 2.

In Figure 3 it can be seen that the inner surface of the telescopic tube 1 above the conical area 9 still has a small step 33, on the edge of which the outer surface of the cylindrical extension 11 can sealingly apply if a linear pressure instead of a flat pressure is preferred. The cylindrical extension 11 also has an insertion aid into the telescopic tube 1 in the form of the rounded outer edges of the cylindrical extension 11.

The flange 6 of the telescopic tube 1 advantageously has the function of a pouring lip, ie when liquid is poured out through the telescopic tube 1, the liquid flows relatively cleanly and defines from the end of the flange 6 without wetting the outer surface of the telescopic tube 1. Even when the pouring process is ended, the liquid essentially drips off from such a pouring lip, so that there is no contamination of the container or the environment.

The conical sealing surfaces 15, 16 on the outside of the telescopic tube 1 and on the inside of the container neck 2 also prove to be advantageous when the container is filled with the telescopic tube inserted. If the container is filled when the telescopic tube 1 is inserted and the liquid level inside the container 8 rises above the lower edge of the inserted telescopic tube 1, and in particular also above the height of the tabs 22 and ventilation openings 23, the outside of the telescopic tube 1 must be in Containers 8 air can escape.

This can easily be done in that the telescopic tube 1 is slightly raised by the pressure rising in the container, so that the conical surfaces 15, 16 disengage from one another and leave a gap for the escape of air.

It is understood that the outer diameter of the telescopic tube 1 below the conical section 9 is slightly smaller than the inner diameter of the container 2, so that here too the air through an annular gap upwards to the conical sealing surfaces 15, 16 and from there further out can escape. The stop surface 10 is also lifted off the upper edge 4 of the container neck 2.

After the container 8 has been completely filled, the screw cap 3 can then be put on and screwed tight, the bead 17 sliding over the outer edge of the flange 6 and the conical sealing surfaces 15, 16 engaging and being pressed together by axial displacement of the telescopic tube 1 until the stop surface 10 of the projection 7 rests on the edge surface 4 of the container neck 2. In this case, the outer surface 14 of the essentially cylindrical, possibly slightly slightly conical extension 11 presses against the inner surface 13 or a step edge provided in this area on the inside of the telescopic tube 1.

Reference list

1

Telescopic tube

2nd

Container neck

3rd

Sealing cap

4th

Edge, area

5

extension

6

flange

7

head Start

8th

container

10th

Support or stop surface

11

approach

12th

Topsoil

13

Inner surface

14

Outside surface

15

area

16

area

17th

Surround

20th

Pull-out lock

21

Locking cams

22

Tabs

23

Vents

24th

area

25th

Safety and guarantee ring

26

head Start

28

External thread

30th

Area

31

area

32

area

33

step

Claims (13)

Container closure with a telescopic tube (1) which can be telescopically extended from a container neck (2) and a closure cap (3) which can be screwed onto the container neck (2), characterized in that the telescopic tube (1) has a radial extension (5) at its upper end, whose outer diameter is larger than the inner diameter of the upper edge (4) of the container neck (2). Container closure according to claim 1, characterized in that the radial extension (5) has a flange-like circumferential collar (6), the outer diameter of which is larger than that of a retaining bead (17) circumferential on the inner wall of the closure cap (3). Container closure according to claim 1 or 2, characterized in that the radial extension (5) has an at least partially lower support surface (10) running in a radial plane. Container closure according to one of claims 1 to 3, characterized in that the telescopic tube (1) has an at least partially conical outer sealing surface (16) in the region of the support surface (10) or below it or below and in the vicinity of its upper edge. Container closure according to one of claims 1 to 4, characterized in that the container neck (2) has at its upper edge a bearing surface (4) which extends essentially in a radial plane. Container closure according to one of claims 1 to 5, characterized in that the container neck (2) has a conical sealing surface (15) below the edge (4) of the container neck (2). Container closure according to claim 6, characterized in that the upper inner edge of the container neck (2) is chamfered. Container closure according to one of claims 1 to 7, characterized in that on the inside of the closure cap a retaining bead is circumferentially arranged at a distance from the bottom (12) of the closure cap (3) which is approximately the thickness of the flange-like collar (6) corresponds. Container closure according to one of claims 1 to 8, characterized in that a retaining bead (17) is formed by two intersecting, conical surfaces (31, 32) which intersect. Container closure according to one of claims 1 to 9, characterized in that the telescopic tube (1) preferably has latching cams (21) in the region of its lower half. Container closure according to claim 10, characterized in that the locking cams are provided in an easily deformable area of the telescopic tube (1), preferably in an area (30) of lesser wall thickness of the telescopic tube (1). Container closure according to one of claims 1 to 11, characterized in that a pull-out lock (20) is arranged below and at a distance from the latching cams and that the telescopic tube (1) above the pull-out lock (20) and seen from top to bottom has a conical shape Extension (24) has. Container closure according to one of claims 1 to 12, characterized in that a cylindrical projection (11) is provided on the inside of the closure cap, the outer surface (14) of which comes into sealing engagement with the inner surface of the telescopic tube or with an edge provided on the inner surface of the telescopic tube .

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