EP1339619B1 - Pressure indicator - Google Patents

Abstract

The invention relates to a pressure indicator (6) for a storage container (15) for food. Said container can be closed in an airtight manner and comprises a connecting device (9) for a vacuum pump used to evacuate the air from inside (22) the storage container (15). The invention is characterised in that the pressure indicator (6) is embodied in the form of a dome-shaped membrane which can fold up into itself. One such pressure indicator (6) facilitates the air evacuation process as the user can see immediately when or if there is still a sufficient vacuum inside (22) the storage container (15). The inventive pressure indicator (6) provides an optically and haptically detectable signal corresponding to the pressure state inside the storage container (15).

Description

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

For storage of food in the household sector systems are already known which allow a preservation under better conditions than if the food is stored untreated or without improved storage conditions. One way to improve food preservation is to store food in containers under vacuum. It has been proven that such systems produce very good results in avoiding some microorganisms, pests, mold and yeast growth. Furthermore, this avoids the oxidation of food, whereby changes in the moisture and aroma of the food can be avoided. A problem with such systems is the assurance of sufficient vacuum in the storage containers, especially over an extended period of time.

A certain type of visual inspection is possible with a container lid according to WO 8/00560 A1. It describes an opening mechanism for a plastic beverage can. The beverage can has a plastic lid, which has a curvature to the outside with appropriate overpressure in the container interior. A quantitative statement about how big the pressure in the container interior, can not meet with it.

The CH 304 374 A discloses a closure cap for a sterilizing vessel made of aluminum, which is formed substantially annular and mounted on a cylindrical aluminum container. Between the edge of the lid and the upper rim of the container, a rubber seal is applied. In the middle of the container lid an additional opening is introduced, which is covered by a rubber cap. The rubber cap is used for visual inspection to indicate if there is a vacuum inside the container. As long as a corresponding negative pressure in the container interior is present, the rubber cap bulges inward accordingly. With decreasing vacuum, this curvature decreases continuously. Therefore, it is difficult for the observer to decide whether the negative pressure existing inside the container is still sufficient to ensure the freshness of the food inside the container.

From FR 269 2 870 A1 a storage container with a pressure indicator and a check valve according to the preamble of claim 1 is known. The check valve is there in the form of a stick out of the lid of the storage container.

From DE 43 42 394 C a valve for evacuated container is known. The valve has a valve body which is connected to a spherical cap-shaped actuator and projects with this from the container housing to the outside.

The present invention has for its object to develop a storage container of the type mentioned in such a way that a simpler version of the valve device is made possible.

This object is achieved by a storage container for food with the features of claim 1 according to the invention in that the pressure indicator and the check valve are made of an elastomeric flat foot section, which presses against the container lid. As a result, the valve device, in particular with regard to its function as a check valve, can be realized in a simple manner. Advantageous embodiments of the invention are described in the subclaims.

The storage container is simple and inexpensive to produce and avoids the disadvantages of the prior art. The pressure indicator simplifies the evacuation process, as it is immediately apparent to the operator when a sufficient negative pressure has been reached in the storage container. The pressure indicator provides an optically and haptically detectable signal for the corresponding pressure state in the interior of the storage container available. In this case, the optical effect of the membrane made of elastomeric plastic material can be increased by appropriate color design in a signal color. Depending on how far the pressure indicator protrudes or disappears over the outer contour of the valve device under appropriate pressure conditions, a corresponding haptic effect can be achieved, which also allows visually impaired users to detect the pressure state in the interior of the storage container.

If the pressure indicator is provided as an additional component to the valve device, that is, the pressure indicator is integrated into the valve device, a component with multiple function is created.

For the foot section, a material is selected which has both sufficient rigidity and the required sealing properties. This component can be inexpensively manufactured as an injection molded component and easily mounted on the storage container.

An advantageous embodiment of the present invention provides the features of claim 2. At ambient pressure in the storage container, the membrane of the pressure indicator is clearly outward.

A further advantageous embodiment of the present invention provides the features of claim 5. As a result, a clear signal position of the pressure indicator is achieved. When a predefined negative pressure inside the container is reached, the membrane "snaps" inwards. With appropriate selection of the spring ensures that the membrane snaps back into its original position when a minimum negative pressure in the storage container is exceeded, i. E. There are only two distinct pressure indicator positions: Sufficient negative pressure in the storage container (pressure indicator is snapped in) / insufficient negative pressure or ambient pressure (pressure indicator is in its initial position). The spring element can be formed for example by appropriate selection of a resilient plastic material for the membrane of the pressure indicator or by inserting a spring metal in the membrane of the pressure indicator.

A further advantageous embodiment of the invention provides the features of claim 6. This makes it possible to store the storage container and its contents in a freezer and then thaw in a microwave oven.

Due to the features of claim 7 results in a particularly well visible pressure indicator that clearly reflects the pressure state.

Due to the features of claim 8, the snap action of the pressure indicator is achieved. As a result, only good or bad state of the vacuum is clearly displayed. A gradual shift of the pressure indicator is thereby avoided.

Due to the features of claim 9, the pressure indicator can be folded particularly frictionless, since the side wall when rolling does not rub against each other appreciably.

Due to the features of claim 10, the pressure state can be particularly easy ermittein, because as soon as the vacuum is too low, the pressure indicator penetrates the display opening, while on the other hand, with sufficient vacuum, the pressure indicator does not penetrate the display opening.

Fig. 1

eine schematische Schnittdarstellung einer ersten Ausführungsform einer Ventileinrichtung mit einem erfindungsgemäßen Druckindikator für einen Behälterdeckel eines Aufbewahrungsbehälters für Nahrungsmittel bei nicht ausreichendem Vakuum im Aufbewahrungsbehälter,

Fig. 2

eine schematische Schnittdarstellung der Ventileinrichtung mit dem Druckindikator nach Fig. 1, wobei sich ein ausreichendes Vakuum im Aufbewahrungsbehälter befindet,

Fig. 3

die Ventileinrichtung nach Fig. 1, jedoch nach Freigabe der Entlüftungsöffnung durch die Öffnungslasche, so daß sich im Aufbewahrungsbehälter wieder atmosphärischer Druck befindet,

Fig.4

eine teilweise geschnittene perspektivische Darstellung einer zweiten Ausführungsform eines erfindungsgemäßen Druckindikators für einen Aufbewahrungsbehälter für Nahrungsmittel bei nicht ausreichendem Vakuum im Aufbewahrungsbehälter,

Fig. 5

wie Fig. 4, jedoch mit nach oben geschwenkter Öffnungslasche zum Freigeben der Entlüftungsöffnung, so daß im Aufbewahrungsbehälter Druckausgleich hergestellt werden kann und

Fig. 6

eine perspektivische Darstellung eines Aufbewahrungsbehälters für Nahrungsmittel mit einem Druckindikator gemäß Fig. 4.

Further embodiments and advantages of the invention will become apparent from the description of the embodiments with reference to the accompanying drawings. Show:

Fig. 1

1 is a schematic sectional view of a first embodiment of a valve device with a pressure indicator according to the invention for a container lid of a food storage container in the case of insufficient vacuum in the storage container;

Fig. 2

1 is a schematic sectional view of the valve device with the pressure indicator according to FIG. 1, wherein there is a sufficient vacuum in the storage container;

Fig. 3

1, but after release of the vent opening through the opening tab, so that in the storage container is again atmospheric pressure,

Figure 4

a partially cutaway perspective view of a second embodiment of a pressure indicator according to the invention for a storage container for food in an insufficient vacuum in the storage container,

Fig. 5

as shown in FIG. 4, but with upwardly pivoted opening tab for releasing the vent, so that pressure equalization can be made in the storage container and

Fig. 6

a perspective view of a storage container for food with a pressure indicator of FIG .. 4

In the following, the same or similar components are identified by the same reference numerals for the sake of simplicity. In order to avoid repetition, the same position numbers must be assigned the same functions and modes of action.

Figures 1 to 3 show a schematic sectional view of a first embodiment of a pressure indicator 6 according to the invention for a storage container 15 (Fig. 4) for food. According to FIGS. 1 to 6, the pressure indicator 6 is connected to a valve device 1, which is attached to a container lid 2. An opening tab 7 is integrally connected to the container lid 2 via a film hinge 32. The opening tab 7 and the container lid 2 are made as an injection molded component made of temperature-resistant thermoplastic material. The opening tab 7, which is designed essentially as an oval plate in plan view, has a connection device 9 for a suction connection of a vacuum pump, which is essentially formed by a smooth annular surface 18 on the outside 24 of the opening tab 7 and one or more suction openings 17 within the annular surface 18.

At the bottom of the opening tab 7, a sealing tongue 3 made of elastomeric plastic is arranged in the figures 1 to 6 below the connecting device 9. The sealing tongue 3 is fixed in the first embodiment in Figures 1 to 3 via an annular ridge 19 on the opening tab 7 and is disc-shaped as a separate component. The web 19 has an air passage 30.

The opening tab 7 is inserted in Figures 1 to 6 in a corresponding to the opening tab 7 adapted, substantially rectangular recess 20 in the container lid 2 of the storage container 15. Under the connecting device 9 of the opening tab 7 and the sealing tongue 3, a vent opening 4 is provided in the container lid 2. In the open state, the vent 4 establishes the connection between the atmosphere and the interior 22 of the storage container 15. When closed, the vent 4 is sealed airtight by the sealing tongue 3. The vent 4 forms with the sealing tongue 3 in the direction of the storage container 15 closing check valve 40th

In addition to the vent 4, a measuring opening 5 is arranged in the container lid 2 according to Figures 1 to 6. The measuring opening 5 is covered airtight from the environment by a plastic membrane 29 of the pressure indicator 6 from above. The pressure indicator 6 extends substantially perpendicular to the plane of the container lid 2 upwards and has, according to Figures 1, 3, 4 and 5 in not properly vacuumized state, a substantially cup-shaped, outwardly slightly curved side wall 23, which tapers upwards and which terminates with a horizontally extending circular bottom 24. The diameter D of the bottom 24 is smaller than the diameter d of the opening 25 at the foot portion 25 of the pressure indicator 6, as shown particularly in FIG. 4. By the described design of the pressure indicator 6 is achieved when vacuum is applied, that the side wall 23 of the pressure indicator 6 similar to a rolling diaphragm draws into its cavity 26, as shown in FIG. 2.

In the opening tab 7 is located according to the figures 1 to 6 at the location of the pressure indicator 6, a display opening 8 through which the pressure indicator 6 extends perpendicularly beyond the outside 33 of the opening tab 7, if there is insufficient negative pressure in the interior 22 of the storage container 15 , The pressure indicator 6 is made of an elastomeric plastic and preferably in a signal color, in the present case in red. On the inside of the pressure indicator 6 is stiffened according to Figures 1 to 3 by a spring element 12, which preferably consists of a resilient material, such as spring steel or elastomeric plastic, and rests flat against the inside 34 of the pressure indicator 6.

At the free end on the right in FIGS. 1 to 6, the edge-closer part of the opening tab 7 has an actuating surface 10. In this case, the end of the opening tab 7, starting from the Abnickkante 35, slightly bevelled upwards. The container lid 2 has the recess 20, so that, since the opening tab 7 is spaced by ribs 29, 36 from the bottom 37 of the recess 20, the actuating surface 10 of the opening tab 7 conveniently between finger and thumb of a user's hand (not shown) gripped and after can be pulled up.

In the figures 1 to 3, a headband 11 is shown, which presses the elastomeric plastic material of the flat foot portion 25 of the pressure indicator 6 to the container lid 2. The headband 11 is supported on walls of the container lid 2, not shown in the drawing. In the figures 1 to 3 so the cup-shaped pressure indicator 6 is integrally connected to the foot portion 25 so that in the clamped state by the headband 11 of the pressure indicator 6 is sealingly connected to the container lid 2.

Figures 4 to 6 show a partially sectioned perspective view of a second embodiment of a valve device 1 with the pressure indicator 6 according to the invention for a storage container 15 for food. Also in this embodiment, the opening tab 7 is integrally connected to the container lid 2 via the film hinge 32. The arranged under the connecting device 9 of the opening tab 7 sealing tongue 3 is connected via a driver 13 with the opening tab 7. Both the sealing tongue 3 as the driver 13, the foot portion 25 and the pressure indicator 6 are made of a single elastomeric plastic part which is attached as an insert to a bead 21 in the recess 20 of the container lid 2. The plastic material used for the pressure indicator 6 has spring properties, so that here, too, said snap effect on the pressure indicator 6 occurs when either too little or sufficient vacuum is present. The difference between the embodiment of Figures 1 to 3 to the embodiment of Figures 4 to 6 is essentially that in Figures 1 to 3, the sealing tongue 3 relative to the pressure indicator 6 forms its own sealing part, whereas in the embodiment of the Figures 4 to 6, these parts are formed by a single elastomeric component, the sealing tongue 3 is partially cut out of the foot portion 25 and thus forms a gap 28.

Furthermore, a peripheral seal 14 is provided at the edge of the container lid 2 according to Figures 4 and 5, which allows an airtight sealing relative to the storage container 15. But it is also conceivable not to use a seal 14, as shown in Figures 1 to 3, so that the lid 2 itself with the storage container 15 is a tight seal. In the closed state of the valve device 1, the foot part 25 is pressed by the circumferential rib 29 against the bottom 37 of the container lid 2 and sealed so.

In the illustration in FIGS. 1 and 3 to 6, the pressure in the container interior 22 of the storage container 15 corresponds to the ambient pressure. The pressure indicator 6 is therefore due to its spring bias through the display opening 8 on the opening tab 7 outwardly out.

In the illustration according to FIG. 2, there is a sufficient negative pressure in the container interior 22 of the storage container 15. The pressure indicator 6 is therefore sucked into the interior of the container 22 into its cavity 26; it is in the folded or snapped-in state. In this state, the pressure indicator 6 is not or only slightly above the outer contour of the opening tab 7 out. The pressure indicator 6 folds like a rolling diaphragm. In this case, the ratio of the diameter D to d in dependence on the wall thickness f and the elastic material of the pressure indicator 6 is selected so that of a certain negative pressure per se, the pressure indicator 6 folds up abruptly, as shown in FIG. Decreases the vacuum in the container interior 22, so here is reached a point where the pressure indicator 6 abruptly moves to the outside. This has the advantage of a clear display.

The operation of the bieden embodiments is the following:

When used in a household, the user can first on the basis of the position of the pressure indicator 6 with closed container lid 2 about the pressure state in the container interior 22 inform. If the bottom of the pressure indicator 6 protrudes through the display opening 8 to the outside, this means that the pressure in the container interior 22 is not sufficient to ensure storage of food under vacuum conditions (see Figures 1, 4 and 6).

Now, the storage container 15 is evacuated according to Figures 1, 3 and 6. During the evacuation process, a suction connection with a circumferential sealing lip of a vacuum pump (not shown) is placed on the connection device 9 of the valve device 1. Then the vacuum pump is put into operation. This automatically opens the vent 4 of the valve device 1, since the suction can lift the sealing tongue 3 of the vent 4 and the air contained in the storage container 15 is sucked by the vacuum pump. According to Fig. 1, air is above the vent 4 on the sealing seat 38 of the sealing tongue 3 laterally past the sealing tongue 3 outside, through the Air passage 30 and sucked out via the connection device 9 to the vacuum pump. Upon reaching a sufficient negative pressure in the space 22 of the storage container 15, the pressure indicator 6 snaps abruptly inwards (Fig. 2). This informs the user that he can end the evacuation process. After lifting the vacuum pump from the connecting device 9, the sealing tongue is pressed onto the edge of the vent opening 3, whereby it is automatically sealed airtight. This process also occurs at each return stroke of the vacuum pump, so that a vacuum in the interior 22 can be established. The vacuum in the interior 22 now keeps the food there for a long time fresh because lack of oxygen prevents oxidation of the food.

To be able to remove fresh food from the storage container 15, one grips with two fingers under the actuating surface 10 and pivots with little effort, the opening tab 7 in Fig. 5 in the counterclockwise direction. In this case, the sealing tongue 3 is lifted off over the webs 19 from the sealing seat 38 upwards and the vent 4 released by the opening tab 7 of FIG. 3. In the embodiment according to FIG. 5, the upper side of the opening tab 7 strikes against the underside of a rim 13 formed on the driver 13 and pulls the driver 13 with the sealing tongue 3 upwards until the sealing tongue 3 lifts off from the sealing seat 38 and against it Turning clockwise upwards (Fig. 5). Air can now according to the figures 1 to 5 via die.Saugöffnung 17 of the connecting device 9 and the vent 4 to flow into the container interior 22.

The container lid 2 can now be removed without significant effort from the storage container 15. Since the sealing tongue 3 is partially separated according to Figures 4 and 5 from the rest of the flat foot portion 25 through the substantially U-shaped gap 28, so it is connected only in the left rear portion 39 with the rest of the foot portion 25, it falls due to their Gravity as a check valve again on the vent 4, so that a vacuumizing is not a problem. But it is also conceivable that the opening tab 7 can be snapped over clip connections on the container lid 2, so that in the closed state thereby the sealing tongue 3, the vent opening 4 closes. In Fig. 3, the sealing tongue 3 is lifted with the pivoting of the opening tab 7 to the film hinge 32 with upward, because it is attached to the opening tab 7 to fulfill the check valve function with play.

6 shows a perspective view of a storage container 15 for foodstuffs made of thermoplastic material with a valve device 1 according to FIG. 4. The storage container 15 has a cuboid container body 16 and a container lid 2 with circumferential rim 27 which is essentially rectangular in plan view. On one of the narrow sides of the container lid 2, the valve device 1 is arranged in a recess 20. In this case, the actuating surface 10 of the opening tab 7 closes off approximately with the outer surface 33 of the container lid 2. Only the pressure indicator 6 projects in an insufficient vacuum from the display opening 8 of the opening tab 7 vertically upwards. In the direction of the container lid interior 22 next to the Druclcindikator 6, the circular connection device 9 can be seen with the smooth annular surface 18 and the suction opening 17, from which the driver 13 protrudes with its brim 27. The brim 27 serves to better entrainment of the driver 13 when the opening tab 7 is pivoted upwards. Due to the lever action, which is formed by the distances R and r (FIG. 5), a relatively small hand force F (FIG. 4) on the gripping surface 10 is sufficient to lift the sealing tongue 3 from the sealing seat 38, if there is still a vacuum inside the container 22 is available. The smaller the distance r and the greater the distance R, the easier it is to open the valve device 1.

Claims (11)

1. Storage container (15) for food, said container being able to be closed in an airtight manner by a container lid (2), the container lid (2) having a connecting device (9) for a vacuum pump used to evacuate air from the interior (22) of the storage container (15), a pressure indicator (6) being provided to indicate the pressure in the interior (22), said pressure indicator (6) being designed as a dome-shaped membrane which can collapse on itself and being connected to a valve device (1) provided on the container lid (2), said valve device (1) being formed by a nonreturn valve (40) which closes in the direction of the interior (22) of the storage container (15), characterized in that the pressure indicator (6) and the nonreturn valve (40) are produced from an elastomeric planar foot section (25) which presses onto the container lid (2).
2. Storage container according to Claim 1, characterized in that the pressure indicator (6) has a spring element (12) such that, at a predetermined pressure, it folds out into its starting position.
3. Storage container according to Claim 1, characterized in that the elastomeric planar foot section (25) is produced from a single piece.
4. Storage container according to Claim 3, characterized in that the nonreturn valve (40) is formed by a movable sealing tongue (3) which is arranged in the foot section (25), is partially cut out from the foot section (25) and, in the closure position, closes a vent opening (4) in the container lid (2) in an airtight manner.
5. Storage container according to Claim 1, characterized in that the pressure indicator (6) indicates only two discrete states, namely sufficient underpressure in the interior (22) of the storage container (15) or insufficient underpressure in the interior (22) of the storage container (15).
6. Storage container according to one of the preceding claims, characterized in that the pressure indicator (6) is made of plastic material suitable for a temperature range of from - 40°C to + 100°C.
7. Storage container according to Claim 1, characterized in that the material of the pressure indicator (6) is a material with a colour that is easy to see.
8. Storage container according to Claim 1, characterized in that the pressure indicator (6) is substantially pot-shaped and has a flat base (24) adjoined by a conically widening annular wall (23).
9. Storage container according to Claim 8, characterized in that the annular wall (23) curves gently outwards.
10. Storage container according to Claim 1, characterized in that the pressure indicator (6), in its starting position, extends outwards through an indicator opening (8) formed on an opening tab (7).
11. Storage container according to Claim 10, characterized in that a peripheral rib (29) is formed on the opening tab (7) and, when the opening tab (7) is closed, said peripheral rib (29) presses the foot section (25) against the base (37) of the container lid (2) and thus permits an airtight closure of the valve device (1) relative to the storage container (15).

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