EP1506936B1 - Closing device for fuel tank - Google Patents

Abstract

The road vehicle fuel tank filler cap closure plug (10) has a central bore (35) in a cylindrical body (11) with a retaining groove (33). An inwardly-directed flange (32) accommodates a spring-loaded non-return valve body (36) allowing fuel to be pumped in. The fuel flows past the valve body and through a narrow bore (40) in a cylindrical block (39) which may be screwed onto place. The fuel flows through a feed tube (45) toward the bottom of the tank A narrow bore (34) at the side of the plug receives the end of a vapor pressure equalization line (44) with its end held above the liquid level by a float (43).

Description

Field of the invention

The invention relates to a closure device for a container for liquid fuel, which ensures regardless of the orientation of the container, a pressure equalization between a gas space of the container and the exterior, further prevents that liquid can escape unintentionally, and also allows liquid removal, without the Closing device must be removed.

State of the art

Numerous fuel fluids already exhibit a comparatively steep rise in the vapor pressure curve with the temperature at typical ambient temperatures. Thus, heating of such liquids in closed fuel containers, e.g. Canisters or tanks, leading to a strong increase in pressure, either the opening of the container and a safe and regulated liquid removal problematic, or even lead to leaking or bursting of the container. This involves high risks, especially in the case of harmful, corrosive, easily flammable and explosive substances.

To preclude such pressure increase, conventional screw cap containers, e.g. Commercially available canisters, often stored in such a way that the closure is not completely tightened so that resulting vapors can escape before an overpressure builds up. However, this is only possible with stationary storage, as there is a risk of leakage of liquid during transport through the vibrations and possible changes in orientation.

There are also containers which have at the top of the container wall a pressure compensation device with a pressure relief valve which opens from a certain internal pressure and allows venting. But this principle works as well when the pressure relief valve is adjacent to the inside of the gas space of the container, so again only for certain orientations of the container. In case of tilting of the container, however, there is a risk that liquid escapes through the pressure compensation device, or that the pressure compensation device is clogged by liquid or otherwise impaired in their functionality. In addition, in most applications it is impractical and / or uneconomical to retrofit simple conventional containers (canisters) with such devices.

For the removal of liquid from a stationary container with an opening at the top of the container, a suction tube is immersed through the opening of the container and sucked liquid. In this case, the opening is not sealed in order to allow a subsequent flow of ambient air for the extracted liquid amount. However, the liquid removal is also possible only in quiet operating conditions, otherwise there is a risk that liquid leaks.

A closure device for a liquid fuel container with a pressure compensation device is described in document US 6 142 345.

Description of the invention

It is an object of the invention to provide devices that help avoid the disadvantages described above.

This object is achieved by devices which ensure a pressure equalization during storage and transport of a fuel container, and at the same time make it possible to remove liquid from the fuel container.

In particular, this object is achieved by the closure device according to the invention with the features of the main claim.

• eine Druckausgleichsvorrichtung, die (derart ausgebildet ist, dass sie bei teilweise gefülltem Behälter) eine Fluidverbindung zwischen einem Gasraum des Behälters und dem Äußeren bereitstellt, wobei die Druckausgleichsvorrichtung eine flexible Druckausgleichsleitung mit einem Schwimmer aufweist, an dem ein Ende der flexiblen Druckausgleichsleitung derart befestigt ist, dass es in den Gasraum mündet;
• eine Flüssigkeitsdurchführung, und
• eine Flüssigkeitssaugleitungseinrichtung, die an einem Ende mit der Flüssigkeitsdurchführung kommuniziert und die an einem weiteren Ende in Flüssigkeit eingetaucht ist, wenn im Behälter Flüssigkeit vorhanden ist.

This closure device for a liquid fuel container comprises:

• a pressure equalization device (designed to provide fluid communication between a headspace of the container and the exterior (when the container is partially filled), the pressure equalization device being a flexible one Pressure equalization line having a float, to which one end of the flexible pressure equalization line is attached so that it opens into the gas space;
• a fluid passage, and
• a liquid suction passage means communicating at one end with the liquid passage and which is immersed in liquid at another end when liquid is present in the container.

The pressure compensation device and the fluid passage of the closure device are designed so that the two, that ventilation / liquid removal is possible even with different orientations of the liquid container.

So is achieved by the flexible pressure equalization line and the float that the end of the flexible pressure equalization line always opens into the gas space, so that no liquid can escape through the pressure compensation device.

The (at least one) further end of the Flüssigkeitsssaugleitungseinrichtung serves as (at least one) suction end and is immersed in the liquid (if present in the container), so that liquid can be sucked out of the container in all possible container layers.

With a rigid design of the liquid suction device, its design greatly depends on the container shape and size for which it is to be used.

It can be realized, for example, in a comparatively complicated manner so that several separate rigid pipe sections lead to the different extremities of the container, so that it is ensured that in any position of the container at least one suction end is immersed in liquid, and the corresponding suction ends so formed are that they close when they do not flow into the liquid, but into the gas space. Such a closing mechanism, a suction end, for example, by a valve, by a float can be actuated counter to a spring force can be realized. Due to the effect of buoyancy, the float opens the valve when the suction end is immersed in the liquid, while otherwise the spring action keeps the valve closed, so that the suction end is closed when it opens into the gas space.

In an alternative and particularly preferred development, the liquid suction line device has an at least sectionally flexible fluid line which, due to its flexibility, is oriented under its own weight in such a way that the open suction end automatically assumes a position close to the lowest point (or the highest accelerated area). occupies and thus opens into the liquid. For example, the flexible fluid conduit may be in the form of an elastic coil or worm which is fixed at one end and whose open end always occupies the lowest position.

If necessary, the flexible fluid line in the area of the suction end can also be weighted.

Preferably, the flexible liquid line is connected in the region of the suction with the float or another float such that the suction end opens below the liquid level in the liquid.

In a preferred embodiment, the closure device also comprises an actuatable locking device, the actuation of which via the fluid passageway establishes a fluid connection between the interior and the exterior of the container. The blocking device can be particularly preferably provided in or on the liquid feedthrough.

With this locking device can be ensured even at high levels and very violent shocks and / or particularly unfavorable container layers that liquid does not escape accidentally.

The locking device can be reversibly or irreversibly actuated, which is meant to be irreversible actuated that the locking device no longer closes after a single press, but remains open.

In general, a reversible locking device is preferred, which is most easily formed by an actuatable valve. The normal state of the valve is closed so that fluid can not escape accidentally. By actuating the valve, the valve is opened, which allows a liquid extraction. Preferably, the actuating mechanism of the valve is designed so that the valve can not be opened unintentionally.

In particular, it is advantageous to design the actuating mechanism in such a way that it can only be actuated by a connection device provided for this purpose, which can be connected to the closure device. For liquid removal then this connection device must be connected to the closure device, for example via a screw or a bayonet connection, wherein the connection process itself can operate the valve, or alternatively can release the opening of the valve via a separate separate operation.

This development prevents accidental or, excludes brute force, improper opening of the container and thus serves, for example, the child safety. It can be practically implemented so that instead of a single element for actuating the actuating mechanism a plurality of punches are provided, all of which must be operated simultaneously, which is possible only by connecting the provided on the connecting device, appropriately trained counterpart ("key lock -Principle").

A substantially reversible barrier means can also be formed by a septum that has to be pierced through a hollow needle to establish a fluid connection and closes again after removal of the hollow needle.

An irreversible locking device can be particularly useful if the closure device is an integral part of the container and this is filled only once and after the beginning of the emptying process is not sooner removed from the associated sampling system until the container is completely emptied.

An example of such an irreversible barrier means may be a ball pressed into a tapered region of the fluid passage to obstruct the conduit cross-section, as e.g. as a closure for ink cartridges for fountain pen is known.

So that the container can still be removed and transported even after opening the irreversible locking device from a removal device, even if it is not emptied, the liquid feedthrough can also be designed so that it can be closed fluid-tight with a lid or plug, even if the locking device was once irreversibly opened.

The above embodiments of the operation of the components of the closure device according to the invention show that the closure device not only allows the removal of liquid from a container, but vice versa - without having to be removed - and the filling of the container with liquid.

For filling the liquid feedthrough is usually conveniently used, wherein according to the volume of liquid supplied, a gas volume can be displaced by the pressure compensation device, so that there is no pressure increase in the container.

Under certain circumstances, however, the pressure compensation device can be used to fill the container with liquid. In this case, it is particularly favorable if at least two pressure compensation lines are provided, so that at least one pressure compensation line can also be used during the filling process for pressure equalization. Using the Pressure Compensating Device for Filling Liquid may be required when the fluid passage has means (eg, a valve) that allow fluid flow in only one direction, namely, from inside to outside. The use of the pressure compensation device for filling liquid, for example, but also be useful if the closure device integral, that is not destructively removable, part of the container and the closure device also has an irreversible locking device for the liquid feedthrough. Then you have to fill the irreversible barrier means for the liquid feedthrough are not damaged, so that the container can continue to be transported without restriction after the filling process.

The closure device according to the invention thus ensures - regardless of the position of the container - a pressure equalization between the container and the outside atmosphere and at the same time allows a liquid removal, without the risk of the liquid splashed or spilled or otherwise escape. If handled properly, a user can never come into contact with the fluid at any time.

Preferably, the closure device is designed such that it can be pressed into the removal opening of a (conventional) liquid container.

Thus, in the case of circular opening cross-sections, the pressure-equalizing device can have the form of a cylindrical or conical or frustoconical insert body which is designed such that it can be pressed into the removal opening of the liquid container in an accurate and sealing manner. In order to better compensate for tolerances, the insert body or at least its peripheral region may comprise an elastic material, so that the contact region between the insert body and the container opening is fluid-tight (gas- and liquid-tight). For example, one or more circular recesses may be provided in the cylindrical peripheral region, in which sealing rings (O-rings) can be used.

For other than circular opening cross-sections, of course, the shape of the insert body must be adjusted accordingly.

Preferably, the closure device has means for attachment to the removal opening, which correspond to those of a conventional closure for the removal opening.

In conventional liquid containers (canisters), the removal opening usually has an external thread for attaching a screw cap (lid) on, wherein the lid is provided with a corresponding internal thread. The closure device can accordingly be advantageously adapted to the shape of such a lid and have such an internal thread for fastening the closure device.

If the container, however, with a cover / plug with external thread, snap closure, bayonet. etc. closed, so the closure device can be designed accordingly.

In contrast to these purely mechanical methods of attaching the closure device, the closure device can also be glued or welded into the removal opening of a liquid container

In a preferred embodiment, the closure device further comprises means facilitating the connection of an external fluid line, e.g. Means that allow the connection of the closure device with the connection device of a fluid delivery system and establishing a fluid connection between the closure device and the connection device.

Furthermore, the pressure compensation device of the closure device preferably comprises a connection means for a venting / venting line to supply gases via the venting / venting line, e.g. to a catalytic burner or an exhaust system, so that the exiting gases / vapors do not or not reach the atmosphere in the immediate vicinity of the container.

Especially in closed rooms and in case of harmful or flammable or explosive vapors, venting of the container should not or should not be carried out to the environment. In these cases, the vapors can be routed via a connected vent line either to a gas outlet, directly into the open, to an absorption device (eg activated carbon), etc. In the case of organic substances, these vapors can preferably be passed through a catalytic burner, which converts them into innocuous substances ("burns").

The use of a ventilation duct may be necessary if the interior of the tank must not come into contact with air, whether for reasons of purity or for safety reasons (oxygen). The ventilation line may for example be connected to an inert gas reservoir.

The pressure compensation device may also (alternatively or additionally) have a pressure relief valve, so that leakage of gases / vapors does not occur continuously. This allows the container to be transported without permanently emitting gases / vapors. The pressure relief valve opens only when a certain minimum pressure in the tank is exceeded. Preferably, the pressure relief valve is also manually operable so that a user or transporter can perform a controlled venting / venting at appropriate times and at suitable locations.

To ensure that no harmful or otherwise hazardous vapor components escape through the pressure compensation device, a filter (e.g., activated carbon filter) may be further provided in the pressure equalization line.

The above object is further achieved by a liquid delivery system comprising a closure device according to the invention and a connection device which is connectable to the closure device in order to establish a fluid connection between the liquid suction line of the closure device and an external liquid line via the closure device.

The liquid delivery system according to the invention is particularly suitable for supplying fuel to a fuel cell system operated with liquid fuel from a fuel tank (tank, canister). Thus, the liquid delivery system may for example be used particularly advantageously to methanol supply of a DMFC (D irect M ethanol F uel C ell) fuel cell system.

The liquid delivery system is not only suitable for liquid extraction, but equally for filling containers with liquid.

In a particularly advantageous development, the connection device of the liquid delivery system is designed such that it actuates the actuatable blocking device of the liquid feedthrough when connecting to the closure device, i. unlocked to provide fluid communication between the liquid space of the container and the exterior of the container.

As an alternative to this easy-to-use automatic unlocking when connecting the connection device and closure device, an increased security can be achieved if the actuating mechanism of the locking device is designed such that it can only be unlocked (connected) by connecting the connection device and closure device, but this process is carried out separately must become.

Preferably, the closure device and, depending on the design of the closure device, the associated connection device are further designed so that gases from the liquid container can be discharged without them get to the environment when the connection device is connected to the closure device or is.

For this purpose, the connection device can be connectable to a gas line for the removal of gases. Alternatively or additionally, filter devices or other gas purification devices may be integrated in the connection device or be connectable to the connection device in order to clean vapors emerging from the container and to separate off pollutants, and optionally to supply a catalytic burner.

The above object is further achieved by a container which is formed integrally with the closure device according to the invention.

In this case, the integral formation can already take place during the production process of container closure device, wherein the filling of the container, as already explained above, can take place via the closure device. Preferably, however, separate opening is provided in the container, which serves to fill the container. This separate opening can be filled with a container, for example, with a conventional Lid, stopper, etc. sealing (ie gas and liquid tight) are completed. In this preferred embodiment, therefore, the separate opening for filling the container is used, while the closure device is used for venting and fluid removal.

However, the integral formation can also take place only after the manufacture and filling of the container, wherein the closure device can be glued, for example, in the opening of the filled container or welded to it. This design is preferred for applications in which it should be excluded or made as difficult as possible for security reasons, that the containers are filled again after emptying by the end user.

To better illustrate the invention, this will be explained below with reference to particularly preferred embodiments with reference to the accompanying figure.

Fig. 1A:

eine perspektivische Ansicht des Hauptkörpers einer erfindungsgemäßen Verschlussvorrichtung, der als Einsatzkörper zur Anbringung in der Entnahmeöffnung eines herkömmlichen Flüssigkeitsbehälters vorgesehen ist;

Fig. 1B:

eine schematische Veranschaulichung der Anbringung des Einsatzkörper von Fig. 1A in der Entnahmeöffnung eines herkömmlichen Flüssigkeitsbehälters;

Fig. 2:

eine schematische Ausgestaltung des Hauptkörpers einer erfindungsgemäßen Verschlussvorrichtung als Aufsatz zur Anbringung an der Entnahmeöffnung eines herkömmlichen Flüssigkeitsbehälters;

Fig. 3A:

eine detailliertere, perspektivische Schnittansicht einer bevorzugten Ausführungsform der erfindungsgemäßen Verschlussvorrichtung gemäß den Prinzipien von Fig. 1A und 1B;

Fig. 3B:

eine Explosionsdarstellung des Hauptkörpers der Verschlussvorrichtung von Fig. 3A;

Fig. 4:

eine detaillierte, perspektivische Explosionsdarstellung einer Anschlussvorrichtung, die zur Verwendung in Kombination mit der in den Fig. 3A und 3B gezeigten Verschlussvorrichtung ausgebildet ist.

Fig. 5:

eine bevorzugte Ausführungsform eines Schwimmers zur Verwendung bei der erfindungsgemäßen Verschlussvorrichtung.

Show it:

Fig. 1A:

a perspective view of the main body of a closure device according to the invention, which is provided as an insert body for attachment in the removal opening of a conventional liquid container;

1B:

a schematic illustration of the attachment of the insert body of Figure 1A in the removal opening of a conventional liquid container.

Fig. 2:

a schematic embodiment of the main body of a closure device according to the invention as an attachment for attachment to the removal opening of a conventional liquid container;

Fig. 3A:

a more detailed, perspective sectional view of a preferred embodiment of the closure device according to the invention according to the principles of Figures 1A and 1B;

Fig. 3B:

an exploded view of the main body of the closure device of Fig. 3A;

4:

a detailed, exploded perspective view of a connection device, which is designed for use in combination with the closure device shown in Figs. 3A and 3B.

Fig. 5:

a preferred embodiment of a float for use in the closure device according to the invention.

In Figs. 1 and 2, reference numeral 50 denotes a conventional commercial plastic liquid container (canister), the discharge opening 52 of which has an external thread for a screw cap. The invention is not limited to such containers with screw thread.

In FIGS. 1A, 1B, 3A and 3B, reference numeral 10 denotes the closure device according to the invention, of which only a perspective (FIG. 1A) or schematic (FIG. 1B) view or of the insert body are sketched in FIGS. 1A and 1B ( without fluid lines, floats, etc.). Details will be described with reference to Figs. 3A and 3B.

First, Figs. 1A and 1B will be described.

1A shows the cylindrical main body of a closure device 10 according to the invention. As FIG. 1B schematically illustrates, this cylindrical main body is designed as an insert body 11 for use in the removal opening 52 of the container 50. At the outer edge of the top of the insert body 11 has a support portion 12 having a diameter which is slightly larger than the diameter of the removal opening 52 of the container 50, so that the insert body 11 can not fall into the container 50.

However, the cylindrical shape of the main body 11 is not necessarily even with a circular opening cross section of the removal opening 52 of the container 50. Alternatively, the main body could be formed, for example, frusto-conical.

The closure device 10 is formed in the preferred embodiment of Figures 1A, 1B, 3A, and 3B so that it is sealingly pressed into the opening of the container 50 so that it can be removed only with considerable effort from the opening.

If such forces are to be excluded during transport and in the field of use of the container 50, no further securing mechanism is required. However, as shown, if the closure device 10 is dimensioned to be insertable into the opening 52 of the container 50, it is still possible with the closure device 10 inserted, the conventional screw cap or similar device (see Fig. 4) to screw the external thread of the container 50, which can be used to secure the closure device 10 in the opening 52 of the container 50. With the device 102 of FIG. 4 which is open at the top but otherwise cover-shaped, the closure device 10 can be clamped in place for transport, without adversely affecting the ventilating operation of the closure device 10. The tightness against the escape of liquid can be ensured by the pressing of the seated on the removal opening of the container support portion 12 of the closure device 10.

The external thread of the container 50 can therefore also be advantageously used to connect a correspondingly formed connection device of a liquid extraction system with the container 50 and thus also with the closure device 10.

An alternative embodiment of a closure device according to the invention is shown in FIG. 2.

The closure device 20 of FIG. 2 is designed for use on the removal opening of the container 50. It is provided in a lower portion with an internal thread 21 which is formed according to the internal thread of the conventional lid. About this thread a tight screw connection between the container 50 and closure device 20 can be made.

The upper portion of the closure device 20 has an external thread 22, which may be formed according to the external thread of the container 50, for example. This thread can be used to connect a connection device of a liquid extraction system with the closure device 20.

With the closure device 20 of FIG. 2, an extremely stable connection between the closure device 20 and the container 50 is possible.

Fig. 3A shows the preferred embodiment of the closure device 10 of Fig. 1A / 1B, wherein the cylindrical insert body 11 is shown in a sectional view.

As already mentioned above, the upper edge of the insert body 11 has a slightly larger diameter than the removal opening of the liquid container in order to form a seating area 12 and thus to ensure seating of the closure device 10 on the removal opening of the container.

In order to improve the lateral tightness to the removal opening, the cylindrical insert body 11 has a circumferential groove 33, in which a sealing ring can be used, the thickness of which is to be selected depending on the exact diameter of the removal opening.

The insert body 11 also has a pressure compensation passage 34 and a fluid passage 35. The pressure compensation passage 34 may further include a pressure relief valve.

The fluid passage 35 has an automatically closing valve 36, which serves as a locking device. On the container side, the liquid feedthrough 35 is extended by a flexible Flüssigkeitsssaugleitung 45, which is provided for the suction of liquid.

On the container side, a pressure compensation line 44 is connected to the pressure compensation passage 34, which in turn is connected at its free end with a float 43 such that the open free end of the pressure equalization line 44 at partial immersion of the device in a liquid in each position above the liquid level (shown lined).

The pressure compensation passage 34, the pressure equalization line 44 and the float 43 thus together form the pressure compensation device of the closure device 10.

Fig. 3B shows the insert body 11 and its main components in an exploded view. These will now be described with reference to Figs. 3A and 3B.

The insert body 11 has axially on a passage 35, which serves as a liquid passage. The passage 35 has at about halfway height a constriction 32 which serves as a valve seat. The valve is formed by a valve body 36 and a compression spring 38 which urges the valve body 36 against the restriction 36 so as to block the passage. The compression spring 38 is mounted in a first, non-continuous axial bore of a cylindrical block 39. This cylindrical block 39 is pressed on the container side of the axial passage 35 of the insert body 11 (possibly also glued). The cylindrical block 39 further has a second bore 40 of smaller diameter which is coaxial-to-first bore; but is continuous, since it serves the liquid transport. For better sealing of the valve body 36 relative to the underside of the constriction 32 of the passage 35, a sealing ring 37 is also slipped over the valve body 36.

Another sealing ring 41 is provided on the upper side of the insert body 11. This does not concern the functioning of the closure device, but the use of the closure device 10 in a fluid delivery system: the sealing ring 41 ensures that a connection device 100 can be fluid-tightly connected to the closure device 10.

FIG. 4 is an exploded perspective view of such a connector 100 designed for use in combination with the closure device 10 shown in FIGS. 3A / 3B.

The connection device 100 comprises a screw cap 102 for attaching the connection device 100 to the removal opening of a liquid container. The screw cap 102 has a recess 103 which is formed so that it can be slipped over the main body 110 of the connecting device 100 and by screwing the screw cap 102 with the external thread of the liquid container-a firm connection of connecting device 100 and closure device 10 causes.

In the main body 110, a bore 115 is provided which serves for ventilation and communicates in the installed state with the pressure compensation passage 34 of the closure device 10 shown in Fig. 3A. In the bore 115, a tube 116 may further be used, to which in turn a Ent (- / Be) vent line can be connected to not discharge gases to the environment (to be supplied from the environment), but via a gas line to a (from a ) Reservoir.

The main body 110 also has a side port 118 communicating with an axial bore in the main body 110.

The lateral port 118 is provided for receiving the end of a fluid extraction line 119, which can be fixedly connected to the main body 110 by means of a locking screw 120. Provided in the axial bore of the main body 110 is a hollow pin 111 protruding therefrom at the bottom of the main body 110 and serving to actuate the valve 36 of the shutter 10 of Figs. 3A / 3B. Thus, when connecting the connector 100 - via the interposed closure device 10 - with the thread of the outlet opening of the container, an outwardly sealed fluid connection is made between the liquid extraction line 119 and the volume of liquid in the container through which liquid can be drawn from the container. A sealing ring 112 adapted to the shape and diameter of the restriction 32 of the closure device 10 ensures that the fluid communication that is established when the two devices of FIGS. 3A / 3B and 4 are used together is sealed to the outside.

The closure device 10 and the connection device 100 may be configured so as to be dependent on one another such that accidental opening of the closure device 10 is virtually precluded and only the use of the suitable connection device 100 makes it possible to remove liquid. Only when properly connected will a shutter mechanism (e.g., valve) be opened in the intermediate cover. When removing the user's contact with the liquid is excluded. Access to the container contents is only granted if the corresponding consumer is connected via the correct removal device.

By floating on the liquid surface float 43 ensures that a vent / vent line 44 opens in any position of the container in the gas phase above the liquid surface.

Also, the liquid withdrawal conduit 45 may be used in combination with the float 43 (or another float) and connected to the float 43 (or other float) so that the suction end at the bottom of the float will always discharge into the liquid ,

The lines may be guided through holes in the float 43, as is sketched for the line 44 in FIG. 3A. But you can also be connected to the swimmer in other ways.

FIG. 5 illustrates how a float 43 can be formed, for example, by a hollow plastic ball 70, to the outside of which the conduit 44 is connected via a heat-shrinkable tube 90. To ensure that the open end of the conduit 44 always opens into the gas phase, a weight 80 can further be provided that stabilizes the position of the float 43.

In particularly critical applications, the venting (rather than the environment) may be controlled, with, for example, a filter (e.g., activated carbon filter) or catalytic burner installed in the venting line. This can prevent emissions from the container into the environment (e.g., in the case of solvent-containing containers) and environmental contaminants into the container.

Claims (16)

1. A closure device (10) for a container (50) for liquid fuel comprising:

   a pressure equalisation device for providing a fluid connection between a gas space of the container (50) and the outside, characterised in that the pressure equalisation device comprises a flexible pressure equalisation pipe (44) with a float (43), on which one end of the flexible pressure equalisation pipe (44) is fastened such that it can open into the gas space;

   a liquid duct (35); and

   a liquid suction pipe (45), which communicates at one end with the liquid duct (35) and which at another end is immersed in liquid when liquid is present in the container.
2. The device (10) according to Claim 1, further comprising:

   an actuatable shut-off device (36), the actuation of which establishes a fluid connection between the interior and the exterior of the container (50) through the liquid duct (35).
3. The device (10) according to Claim 2, in which an actuation mechanism of the actuatable shut-off device (36) is formed such that it can be actuated only by a connection device specially provided for that purpose which can be connected to the closure device.
4. The device (10) according to Claim 2 or 3, wherein the shut-off device of the liquid duct comprises an actuatable valve.
5. The device (10) according to one of the aforementioned claims, wherein the liquid pipe (45) is flexible at least in some sections.
6. The device (10) according to Claim 5, wherein the further end of the flexible liquid pipe (45) is weighted with at least one weight.
7. The device (10) according to one of the Claims 5 or 6, wherein the further end of the flexible liquid pipe (45) is connected to the float (43) or to a further float.
8. The device (10) according to one of the aforementioned claims, which is formed such that it can be pressed into the removal opening (52) of the liquid container (50).
9. The device (20) according to one of the aforementioned claims, which comprises devices (21) for fitting to the removal opening (52), which correspond to the devices (11) of a conventional closure for the removal opening (52).
10. The device according to one of the aforementioned claims, comprising:

    a connection device for an external liquid pipe.
11. The device according to one of the aforementioned claims, comprising:

    a connection device for a venting / ventilation pipe.
12. The device according to one of the aforementioned claims, in which the pressure equalisation device comprises a pressure relief valve.
13. A liquid conveyance system, in particular for the supply of fuel to a fuel cell system comprising:

    a closure device (10) according to one of the aforementioned claims;

    a connection device (100), which can be connected to the closure device (10), to establish a fluid connection between the liquid suction pipe (45) of the closure device (10) and an external liquid pipe (119) via the closure device (10).
14. The liquid conveyance system accord ing to Claim 13, wherein the connection device (100) is formed such that it actuates the actuatable shut-off device (36) of the liquid duct (35) on connection to the closure device (10) in order to provide a fluid connection between the liquid space of the container and the outside of the container (50).
15. The liquid conveyance system according to Claim 13 or 14, wherein the connection device (100) is formed such that gases can be passed from the liquid container (50) without them accessing the environment when the connection device (100) is connected to the closure device (10).
16. A container with a closure device (10) according to one of the Claims 1 to 12.

Images