WO2004005159A1

WO2004005159A1 - Improved valve arrangement for a foodstuff storage container

Info

Publication number: WO2004005159A1
Application number: PCT/EP2002/014693
Authority: WO
Inventors: Sergi Gili; Mariano Peñaranda; Jose Millan
Original assignee: Braun Gmbh
Priority date: 2002-07-09
Filing date: 2002-12-21
Publication date: 2004-01-15
Also published as: DE10230748C1; AU2002360076A1

Abstract

A valve arrangement for a foodstuff storage container, comprising a connector device for evacuation of the storage container, a device for pressure equalization between the environment and the storage container and a device for displaying the container pressure is characterised in that the valve device (1) comprises a valve housing (4) and a valve housing cover (5), between which a membrane (2) is arranged. According to the invention, the improved valve device has several advantage over the state of the art. Firstly a compact easily-assembled component with few parts is achieved, which can be exchanged or renewed as required. This is of advantage with a sudden loss of sealing or similar. In said sandwich construction, a multi-functional component is provided, which permits a connection to a vacuum pump, a pressure indicator and a ventilation function. A complicated housing system for ventilation of the vacuum container before opening which is liable to faults can be avoided by means of said valve device. Components important for sealing are now exclusively mounted on the valve device and not on the container lid.

Description

Improved valve device for a food storage container

The invention relates to an improved valve device for a food storage container according to the preamble of patent claim 1.

Systems are already known for the storage of foodstuffs, which allow preservation under better boundary conditions compared to untreated foodstuffs or foodstuffs stored without improved storage conditions. One possibility for this concerns the storage of food in containers under vacuum. Such systems have been shown to produce very good results in avoiding microorganisms, vermin, mold and yeast growth. It also prevents the oxidation of food, which can prevent changes in the moisture and aroma of the food. However, it is often difficult to open corresponding storage containers, since the vacuum inside the container sucks the container lid. In addition, it is often not recognizable to the user whether the desired vacuum is still present in the storage container.

Lids for food storage containers are already known from the prior art, in which a vent or ventilation valve is provided in the container lid for pressure compensation during the warming-up process in a microwave oven.

Such a mechanism is described, for example, in EP 0 633 196 A2. The object is to prevent the build-up of excess pressure in the interior of a storage container for foodstuffs which is heated in a microwave. This usually happens when there are aqueous liquids inside the container that evaporate when heated and thereby build up excess pressure in the container. This is particularly disadvantageous when opening the container lid, since sauces or other food components suddenly spurt out when the lid is opened. For this purpose, EP 0 633 196 A2 proposes a vent valve in the lid of the food storage container, which is to be opened by the user before the container is introduced into the microwave oven. The water vapor which then arises during the warming-up process can thereby escape unhindered without a corresponding vapor pressure building up inside the sealed container. An improved storage of food under vacuum and an indication of the pressure prevailing in the container should not be achieved by this. EP 0 820 939 A1 is also based on the object of preventing the build-up of excess pressure in the interior of the storage container for foodstuffs which are warmed up in a microwave. Ie, a venting option for storage containers for foodstuffs is to be made available here in order to be able to safely warm up the foodstuffs stored therein in a microwave oven with the container lid closed.

In contrast to EP 0 633 196 A2, however, a valve mechanism is described that can be opened via a joint, such as a rocker. Thus, all that is required is to press the rocker arm in, making the valve easy to open. Here, too, no improved possibility for storing food under vacuum or an indication of the pressure conditions prevailing in the container is to be created.

WO 88/00560 describes an opening mechanism for a plastic beverage can. First of all, by opening a ventilation valve, pressure equalization is to be created, which facilitates the subsequent opening or removal of the entire cover. In particular, the balancing of excess pressure inside the container, which arises, for example, from carbonated drinks, plays a role in this prior art. Neither reclosing with the appropriate pressure build-up nor an indication of the pressure prevailing in the container is provided with this system.

Finally, DE 100 60 999 C1 describes a storage container for food with a container lid, in which an opening mechanism is provided for ventilating the evacuated container before opening. According to one embodiment of this prior art, a sealing tongue is lifted off a vent opening via a driver. The sealing membrane and a pressure indicator are attached directly to the container lid. The opening tab is permanently connected to the container lid by a film hinge. Although this solution already offers an improved possibility for storing food under vacuum, opening the lid is facilitated by prior ventilation and the pressure status inside the container is indicated by a pressure indicator. Disadvantages of this known solution are, on the one hand, the complex assembly of the sealing components directly on the container lid and, on the other hand, the complicated driver mechanism of the check valve which is prone to defects. Furthermore, an exchange of the valve mechanism in the known system is only possible to a limited extent. The present invention is therefore based on the object of providing an improved valve device for a storage container for foodstuffs with a connecting device for evacuating the storage container, with a pressure indicator and a ventilation device. It should be possible to remove the container lid from the evacuated container easily and without great effort. The assembly of the valve device during manufacture is to be carried out inexpensively as a compact and robust component and to enable simple replacement of the storage containers supplied for repair purposes.

This object is achieved by a valve device for a storage container for food with the features of claim 1. Advantageous refinements and developments of the invention are described in the subclaims.

The improved valve device according to the present invention has several significant advantages over the known prior art. On the one hand, a compact, easy-to-assemble valve device with few components is created, which can be replaced or renewed if necessary. This is e.g. advantageous if there is a sudden leak or the like. A multi-functional component is provided in the sandwich construction according to the invention, which enables both a connection for a vacuum pump, a pressure display and a ventilation function. In addition, the valve device according to the invention makes it possible to dispense with a complicated driver system, which is susceptible to defects, for ventilating the vacuum container before opening. Seal-relevant components are now attached to the valve device according to the invention.

The components of the valve device are provided separately from the storage container for foodstuffs as separate components which, according to the advantageous embodiment according to claim 2, are detachably attached to the latter. On the one hand, this enables simple assembly during manufacture and, on the other hand, it enables repair or replacement of defective valve devices. In addition, the manufacture of the valve group can be outsourced to suppliers.

The valve device can be arranged on the container wall or on the container lid, the latter being particularly suitable for this, since the attachment of a vacuum pump to the container lid is particularly simple. The connection to the container lid can be made in an advantageous manner according to claim 3. For example, the hinge can be integrally formed on the valve housing. By choosing one Material with inherent spring properties, the hinge can simply be snapped into a hinge receptacle attached to the container lid, for example.

A further advantageous embodiment provides the features of claim 4. The membrane is advantageously made of an elastomeric plastic material, such as polybutadiene, butadiene-styrene polymer, acrylonitrile copolymer, polychlorobutadiene, isoprene rubber, post-treated polyolefins, polyurethane, silicone rubber or the like. manufactured. This includes the use of natural rubber, cork, etc. but not generally.

A further advantageous embodiment provides the features of claim 5. The sealing tongue can be designed, for example, by a U-shaped cutting line in the flat membrane, the sealing tongue lying flat on a ventilation opening on the storage container or on the container lid in the closed state.

Another advantageous embodiment of the present invention provides the features of claim 6. The pressure indicator can, for example, be connected in one piece to the membrane.

Particularly advantageous alternative configurations of the pressure indicator are described in patent claims 7 and 8. It is advantageous in the embodiment according to claim 7 that the Federsteif ig speed also retrospectively to the desired response pressure, i.e. to the value of the tank pressure at which the pressure indicator triggers, can be set or selected. The advantageous embodiment according to claim 8 is characterized by a reduction in the number of components required and simple assembly.

Another advantageous embodiment of the present invention provides the features of claim 9. This avoids an additional sealing element and keeps the number of components low.

Another particularly advantageous embodiment of the invention is described in claim 10. The valve housing and the valve cover can also be produced in one injection molding process during injection molding and can be connected to one another for example by a film hinge. Further refinements and advantages of the invention are explained by the following description of the exemplary embodiments with reference to the accompanying drawings. In it show:

Figure 1 is a schematic sectional view of a first advantageous embodiment of an improved valve device in the installed state.

FIG. 2 is an exploded perspective view of the valve device from FIG. 1;

3 shows a perspective view of a second advantageous embodiment of an improved valve device in the installed state;

FIG. 4 is an exploded perspective view of the valve device from FIG. 3.

In the following, identical or similar components are identified by the same reference symbols.

1 shows a schematic sectional view of a first advantageous embodiment of an improved valve device 1 according to the present invention in the installed open state. The improved valve device 1 is shown again in FIG. 2 for clarification as a perspective exploded view.

The valve device 1 is attached to a container lid 9 of a food storage container 21. It serves there, on the one hand, by means of a connecting surface 15 and a suction opening 17, to evacuate the closed container 21 and, on the other hand, to ventilate the evacuated container 21 for easy opening of the container lid 9. In addition, the container vacuum is integrated into the valve device 1 by means of a pressure indicator 13 displayed.

The container lid 9 sits in the closed state on a container wall 8 of the storage container 21 and seals it together with a container seal 7 formed as a circumferential flat seal made of elastomeric plastic. The container lid 9 made in the present exemplary embodiment from thermoplastic plastic has an elongated recess 26 for receiving the valve device 1. In the recess 26 there is a measuring opening 12 with a circular cross section and a ventilation opening. 11 provided with a circular cross-section. The vent opening 11 is attached to a frustoconical projection.

The valve device 1 according to FIGS. 1 and 2 has a valve housing 4 made of thermoplastic material. The valve housing 4 has an elongated shape tapering in one direction with rounded ends and peripheral edge 23. A hinge 18 is integrally formed on the valve housing 4 at the wider end.

The circumferential edge 23 encloses a flat plastic surface 27 which, in its wider section, which is arranged at the level of the ventilation opening 11, has a first circular recess 24 concentric with the ventilation opening 11. The edge 23, which virtually forms a circumferential wall, projects vertically above and below the plastic surface 27. Furthermore, in the narrow section of surface 27, i.e. in the area of the pressure indicator 13, a second circular recess 25 is provided.

The peripheral edge 23 serves on the one hand as a boundary and receptacle for a membrane 2 and on the other hand as a clamp connection for a valve housing cover 5. The valve housing cover 5 is also made of thermoplastic material. It has essentially the same outer contour as the valve housing 4. In the area of the first recess 24, a lenticularly curved connecting surface 15 with a central suction opening 17 is provided. A circular indicator opening 14 is provided in the valve housing cover 5 in the area of the second recess 25. The membrane 2 is pressed against the plastic surface 27 of the valve housing 4 by means of webs arranged on the inside of the valve housing cover 5.

The membrane 2 is an essentially flat sealing insert made of elastomeric plastic, which fulfills several functions simultaneously. On the one hand, the membrane 2 at the level of the vent opening 11 and the suction opening 17 has a U-shaped incision, the so-called sealing tongue 10. The sealing tongue 10 acts as a check valve, that is, during the suction process by means of a vacuum pump, not shown, which is connected to the Pad 15 is attached, the sealing tongue 10 lifts off the vent 11. As soon as the vacuum pump is stopped, the sealing tongue 10 closes the vent opening 11 due to the negative pressure generated in the container 21.

On the other hand, a region of the membrane 2 is designed as a pressure indicator 13 which indicates the vacuum state in the interior of the container. If there is sufficient space in the storage container 21 vacuum, the approximately hemispherical pressure indicator 13 is pressed against the pressure of a spring 3 in the direction of the container 21, quasi like an accordion. When a limit value is exceeded or when the pressure between the interior of the container and the surroundings is equalized, the pressure indicator 13 is pressed out through the indicator opening 14 by the compression spring 3 designed as a helical spring. The compression spring 3 is held in a spring receptacle 19 on the valve housing 4.

Finally, in the valve device 1 according to the embodiment shown in FIGS. 1 and 2, a sealing ring 6 is provided in the region of the second recess 25, which seals the connection of the valve housing 4 to the measuring opening 12 in the container lid 9.

After the storage container 21 has been filled with food, the container lid 9 is placed on the container wall 8 provided with a container seal 7. The valve device 1 is closed, that is to say the foods are packaged in a gas-tight manner. Now the air enclosed in the container 21 is sucked off by means of a vacuum pump (not shown) via the suction opening 17, the sealing tongue 10 and the ventilation opening 11. So that only air is sucked out of the container 21 and not from the environment, a sealing edge 22 is formed on the membrane 2, which seals the frustoconical elevation around the vent opening 11. Reaching the required minimum negative pressure can be read from the pressure indicator 13. The pressure indicator 13 disappears in the indicator opening 14 as soon as the required negative pressure is reached.

If pressure equalization occurs over time, this is indicated by a possibly colored pressure indicator 13 from a critical point, which then protrudes through the indicator opening 14, i.e. is pressed by the spring force of the spring 3 beyond this. When the pressure indicator 13 indicates pressure compensation can be defined by appropriate selection of the spring stiffness of the spring 3.

To open the container lid 9, which is firmly sucked in by the negative pressure in the container, the valve device 1 is first gripped by the handle 16 and pivoted about the hinge 18. As a result, the sealing tongue 10 is lifted from the vent opening 11 and the sealing ring 6 from the sealing seat 28 and the storage container 21 is ventilated. After venting, the container lid 9 can easily be lifted off the container 21. 3 shows a perspective view of a second advantageous embodiment of an improved valve device 1 in the installed state. FIG. 4 shows an exploded perspective view of the valve device from FIG. 3.

In contrast to the first embodiment of the valve device according to the invention shown in FIGS. 1 and 2, the second embodiment of the invention according to FIGS. 3 and 4 essentially has three components, namely the valve housing 4, the valve housing cover 5 and the membrane 2.

This is made possible in particular by the changed design of the pressure indicator 13, which is made of a material with an inherent spring stiffness. This eliminates the compression spring provided in the first embodiment. In addition, the integration of a sealing lip 20 at the lower edge of the pressure indicator 13 saves an additional sealing ring for sealing the measuring opening 12.

Otherwise, the structure and function of the valve device 1 according to the second advantageous embodiment corresponds to that described for FIGS. 1 and 2, which is why a repetition at this point is omitted.

The valve devices shown merely describe advantageous configurations of the invention and do not represent any restriction of the scope of protection of the invention defined in the claims.

Claims

claims:

1. Valve device for a storage container for food, which has a connecting device for evacuating the storage container, a device for pressure compensation between the environment and the storage container and a device for displaying the container pressure, characterized in that the valve device (1) has a valve housing (4) and has a valve housing cover (5), between which a membrane (2) is arranged.

2. Valve device for a storage container for food according to claim

1, characterized in that the valve device (1) is removably arranged on the storage container (21).

3. Valve device for a storage container for food according to claim 1 or 2, characterized in that the valve device (1) via a with the valve housing (4) connected hinge (18) preferably pivotally connected to the container lid (9) of the storage container (21) is.

4. Valve device for a storage container for food according to one of the preceding claims, characterized gekennzeic net that the membrane (2) is made of an elastomeric plastic material.

5. Valve device for a storage container for food according to one of the preceding claims, characterized in that the membrane (2) has a sealing tongue (3) which serves as a check valve.

6. Valve device for a storage container for food according to one of the preceding claims, characterized gekennzeic net, that a mechanical pressure indicator (13) is provided as a device for displaying the container pressure.

7. Valve device for a storage container for food according to claim 6, characterized in that the pressure indicator (13) is pressurized by a spring (3).

8. Valve device for a storage container for food according to claim 6, characterized in that the pressure indicator (13) is made of a material with a corresponding spring stiffness.

9. Valve device for a storage container for food according to one of the preceding claims, characterized in that on the membrane (2) surrounding the vent opening (11) sealing edge

(22) is provided.

10. Valve device for a storage container for food according to one of the preceding claims, characterized ge enn eic net that the valve housing (4) and the valve housing cover (5) are made of a suitable injection molded thermoplastic, preferably made of polypropylene, polyethylene or polyamide.