WO2002046044A1

WO2002046044A1 - Device for emptying a food storage container which can be sealed by means of a valve

Info

Publication number: WO2002046044A1
Application number: PCT/EP2001/013147
Authority: WO
Inventors: Montserrat Vilalta; Jose Millan; Juan Carlos Coronado; Mariano Penaranda; Antonio Rebordosa
Original assignee: Braun Gmbh
Priority date: 2000-12-08
Filing date: 2001-11-14
Publication date: 2002-06-13
Also published as: MXPA03003096A; KR20030051759A; DE50103676D1; PL364383A1; DK1339608T3; AU2002214052C1; BR0115272A; AU2002214052B2; EP1339608B1; RU2283801C2; BR0115272B1; DE10060996C1; ES2228960T3; AU1405202A; CN1478033A; JP2004515679A; CN1248639C; KR100582877B1; ATE276137T1; HK1060551A1

Abstract

The invention relates to a device for emptying food storage containers. The invention is characterised in that the device is embodied as an attachment (1) for a hand-held electrical household appliance, particularly a rod mixer and comprises a vacuum pump (17). The invention also relates to a method for emptying a food storage container, whereby an attachment comprising a vacuum pump is disposed on a rod mixer. The inventive attachment is advantageous in that it is provided with a small, economical and easy to handle vacuum pump for use in the household. In contrast to prior art no completely new household appliance with corresponding additional storage requirements needs to be added. The inventive attachment is simple and safe to use in the household.

Description

Device for evacuating a food storage container closable by a valve

The invention relates to a device according to the preamble of patent claim 1.

Systems are known for the storage of foodstuffs which allow preservation under better boundary conditions than if the foodstuffs are stored untreated or without improved storage conditions. One way to improve food storage is to store 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 avoids the oxidation of food, thereby avoiding changes in the moisture and aroma of the food.

To create such storage conditions, a device is required that draws air from the storage container to create a vacuum. A wide variety of pumps are known from the prior art in order to accomplish this task. The pumps intended for use in the household are usually based. on piston pumps or fans.

US 5,195,427 discloses a generic, electrically operated hand-held vacuum pump for use in the household sector. The handheld device, which is designed exclusively as a vacuum pump, is composed of a large number of individual parts. In particular, a complex conversion of the rotary shaft movement into an oscillating movement and a corresponding reduction gear are provided in order to drive the piston pump. The system is intended for the evacuation of food storage containers. With this device, a suitable pressure ratio for storing food in a vacuum container can be easily achieved.

From DE 195 04 638 A1, a hand blender for stirring or chopping food is known, the rotating knife in a bell-shaped recess generates a vacuum when rotating, which via a fluid connection from the upper part of the Stick mixer is brought about. The vacuum accumulating in the bell is used for better and more intensive mixing of food.

A device for generating a vacuum in a container is known from German utility model 299 20316 U1, in which a vacuum cleaner is used as the vacuum generator. For this purpose, an adapter piece is used as an attachment to a vacuum cleaner, which can be placed on a valve formed on the cover of the container. The handling of the vacuum generator designed as a vacuum cleaner is complex and complicated. Hygienic problems can arise when handling food.

The ^' presented electric vacuum pumps for the household area are very complex to manufacture, since linkages and gears require a large number of components. Furthermore, the structural design also requires relatively large device dimensions. In addition, the purchase of an appropriate vacuum pump means that an additional household appliance has to be stored, which is only used in some cases.

The present invention is therefore based on the object of providing a device for evacuating storage containers for foodstuffs which is simple and inexpensive to produce.

This object is achieved by a device for evacuating a storage container for foodstuffs which can be closed by a valve and has the features of patent claim 1. Advantageous embodiments of the invention are described in the subclaims.

The attachment according to the invention for a hand-held electrical household appliance has the advantage that it provides a small, inexpensive and easy-to-handle vacuum pump for household applications. In contrast to the solutions known from the prior art, no completely new household appliance with the corresponding additional space requirement is added. Rather, the attachment complements the existing attachments, such as stirrers, choppers, etc., with another useful component. This is particularly space-saving and much cheaper than an additional electrical device with its own drive. The attachment according to the invention is also simple and safe to use in the household area. The invention represents a simple and inexpensive solution, since the connection of the two shaft ends takes place by simply plugging the shaft couplings together. The shaft couplings can be designed as spur gears.

An advantageous embodiment of the present invention provides the features of claim 2. This type of vacuum pump is particularly characterized by a higher suction power compared to the vacuum pumps previously used for household applications. Furthermore, this allows a low overall height to be realized, since no complex linkages and gears are necessary. The vacuum pump can be driven directly with the speed of the drive shaft of the household appliance. This also reduces the number of components, which in turn has a positive effect on the manufacturing costs. Finally, with such a vane pump, the desired pressure level can be generated in a food container within a few seconds.

A further advantageous embodiment of the present invention has the features of patent claim 3. The sealing lip is formed by a circumferential edge made of elastomeric plastic material that protrudes at the end on the suction side. The cross section of the sealing lip can widen towards the free end. This enables the attachment to be simply placed on a corresponding valve of a food storage container. Centering with a corresponding valve opening, as is required in the devices from the prior art, is thereby avoided. The sealing lip acts like a suction cup.

Yet another advantageous embodiment of the present invention provides the features of claim 4. This enables a simple and inexpensive plug-in connection with a hand-held household appliance, for example a hand blender. This connector is very stable on the one hand and can also serve as a centering for the connection of the shaft coupling.

Finally, an advantageous embodiment of the invention provides the features of claim 5. This creates an additional safety function that prevents liquid from entering the pump chamber during the evacuation process. The solution is simple and inexpensive. For example, a simple rather spherical float provided in a riser. be that floats when a predetermined liquid level is reached and closes a valve opening.

An advantageous further development provides the features of claim 6. This ensures that the vacuum pump of the attachment is temperature-resistant in its operating range. In addition, a self-lubricating effect is achieved. This contributes to the vacuum pump having low pressure losses and being maintenance-free.

Another advantageous development provides the features of claim 7. This also ensures temperature resistance within the operating range. Furthermore, the centrifugal forces occurring are coped with without unduly large deformations. The material-related lightweight construction also contributes to this.

Finally, a further advantageous development has the features of claim 8. The lamellae, for example in the form of rectangular disks, can either be freely movable, operated solely by centrifugal force, or else spring pressure can be applied. A self-lubricating, maintenance-free design is made available through the appropriate choice of materials.

A further advantageous embodiment of the attachment according to the invention provides the features of patent claim 9. This choice of material represents a cost-effective hygienic design that enables a variety of shapes. Some of the possible materials are, for example, polyethylene, polypropylene, polyamide or any other suitable thermoplastic.

Further refinements and advantages of the invention are explained by the description of the exemplary embodiments with reference to the accompanying drawings. In it show:

Figure 1 is a schematic sectional view of a first embodiment of an inventive device for evacuating a storage container for food.

FIG. 2 shows an exploded perspective view of the device from FIG. 1; FIG. 3 shows a perspective detailed view of the vane pump which is part of the device from FIG. 1;

4 shows a perspective view of a hand blender with an attachment according to the embodiment from FIG. 1;

5 shows a schematic sectional illustration of a second embodiment of a device according to the invention for evacuating a storage container for foodstuffs with a float area;

6 is a diagram showing a comparative overview of the evacuation time for a 700 ml container between an attachment according to the invention and conventional vacuum pumps for the household area.

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

1 shows a schematic sectional illustration of an advantageous embodiment of an attachment 1 according to the present invention. The attachment 1 has a coupling section 2, a pump section 3 and a suction section 4.

The coupling section is formed by a pot-like plug-in shaft 6 and a coupling toothing 7 arranged therein. The plug shaft has a bottom opening 9 in its bottom region, through which a shaft 8 connected to the coupling toothing 7 is passed.

The vacuum pump arranged in the pump section 3 is designed as a vane pump 17, as is also shown in the detailed perspective view in FIG. 3. The pump housing of the vane pump 17 is formed by a graphite ring 16, which is covered at its upper and lower ends by a circular upper end plate 18 and a lower end plate 12. A cylindrical rotor 10 is rotatably mounted eccentrically in the pump housing. The rotor 10 has radial grooves 32 arranged uniformly distributed. Radially displaceable slats 11 are accommodated in the grooves 32. The fins 11 are pressed against the graphite ring 16 by centrifugal force, supported in the present exemplary embodiment by the force of springs 26. As a result, the crescent-shaped expanding and narrowing conveyor cells 22 are formed.

As can be seen in FIG. 1, the rotor 10 is connected to a shaft 8 which is guided through the end disk at one end. The end of the shaft 8 protruding from the upper end disk 18 has a coupling toothing 7 designed as a spur toothing. Furthermore, an annular casing is provided in the coupling section 2, which is continued on the wall of the housing 5. This shaft-side housing end of the attachment 1, designed as a plug-in shaft 6, is provided for connection to the tool-side end of a hand blender.

At the other end of the housing 5, a circumferential sealing lip 13 made of elastic rubber material is formed on the outer circumference and is connected to a web 14 via a groove 15. The sealing lip 13 is designed so that it acts as a type of suction cup during operation. The cover 33 attached to this end of the housing 5 has corresponding suction slots 28. The suction slots 28 lie within the section of the cover 33 surrounded by the annular sealing lip 13.

FIG. 2 is a schematic exploded view of the embodiment according to FIG. 1. This shows the plug shaft 6, which is formed in the coupling section 2 and is essentially pot-shaped, and the coupling toothing 7 arranged on the bottom thereof. Furthermore, the rotor 10 and the shaft 8, which connects the coupling toothing 7 to the rotor 10, are shown schematically in the pump section 3. The rotor 10 is received by the graphite ring 16, which in turn is arranged in the housing 5. Finally, the suction connection 4 with the sealing lip 13 made of elastomeric plastic is shown at the lower end of the elongated cylindrical housing 5.

FIG. 3 schematically shows a perspective detailed illustration of the vane pump 17 from FIG. 1. This shows the opened upper end plate 18, which, like the cylindrical graphite ring 16 and the lower end plate 12, is made of graphite. A bore is formed eccentrically to the center of the circular upper end disk 18, which serves as a shaft bearing 20 of the rotor shaft 8, not shown here. The shaft bearing 20 is designed as a self-lubricating plain bearing. Within the cylindrical graph phitrings 16, which together with the upper end plate 18 and the lower end plate 12 forms the pump housing of the vane pump 17, the rotor 10 carried by the shaft 8 is arranged.

The rotor 10 made of carbon fiber is arranged eccentrically to the center of the graphite ring 16. It has three grooves 32, each offset by 120 °, in which slats 11 which are longitudinally displaceable are guided in the radial direction. The slats 11 are essentially made of rectangular graphite disks. The fins 11 are acted upon by spring pressure from compression springs 26 at their end facing the shaft bore 21 of the rotor 10. Furthermore, the suction opening 19 arranged on the lower end disk 12 is shown, through which air is sucked in from a storage container. The conveyor cells 22 are formed by the rotor 10, the upper end plate 18, the lower end plate 12, the graphite ring 16 and the fins 11.

During operation of the vane pump 17, the rotor rotates at the speed of the hand blender 23. The fins 11 slide along the inner wall of the graphite ring 16 due to the centrifugal force and due to the spring force, thus ensuring that no pressure equalization takes place between the different delivery cells.

4 shows a perspective view of an attachment 1 according to the invention, which is mounted on the output end of a hand blender 23. The substantially elongated cylindrical device combination has a handle 24 at its upper end, which can be completely gripped by the hand of a user. On the front of the hand blender 23 there is an actuation switch 25 in the upper area, which can be easily operated by the holding hand.

The upper region of the housing 5 of the attachment 1, which is designed as a plug-in shaft 6, is pushed over the slightly conical output end of the hand blender 23. During this process, the shaft connection for driving the vacuum pump is made at the same time.

At the lower end of the attachment 1, a circumferential sealing lip 13 made of elastomeric plastic is arranged. The smooth, thermoplastic plastic outer walls of the hand blender 23 and the attachment 1 allow easy cleaning of the Device combination, which is particularly important for hygienic reasons in household appliances.

During operation, the attachment 1 is connected to the output end of the hand blender 23. The attachment 1 is held by the annular casing on the output end of the hand blender 23 against rotation and tilting. The output shaft of the hand blender 23 is in positive connection with the coupling teeth 7 of the vane pump 17. The suction side of the attachment 1 sits on a valve device which is attached to a storage container for food. The circumferential sealing lip 13 is sucked onto a smooth circumferential edge of a connection device of the valve device. During the evacuation of the storage container, the rotor 10 of the attachment 1 is set in rotation by the drive shaft of the hand blender 23.

5 shows a second embodiment of the present invention, in which a float area 29 is additionally provided. This prevents the penetration of liquid into the vane pump 17. In this embodiment, the construction of the coupling section 2 and the pump section 3 essentially corresponds to the construction described for FIGS. 1 to 4.

In this embodiment, the pump section 3 is followed by a float region 29. The float region 29 is essentially formed by a cylindrical float housing 31 made of thermoplastic material. The float housing 31 has at its lower end a web 14 which engages in a groove 15 of a sealing lip 13 which forms the suction connection 4.

A spherical float 30 is provided in the float housing 31. The float 30 is designed as a hollow body so that it floats easily on the inflowing liquid. When the liquid level in the float housing 30 reaches a critical value, the lower opening of the suction pipe 27 is closed by the float 30. So no liquid penetrates into the vane pump 17. In order to ensure the suction of the air present in a storage container for foodstuffs, additional suction slots 28 are provided at the lower end of the float housing 31. FIG. 6 shows a diagram in which the evacuation time for a 700 ml container is shown. The time t in seconds is plotted on the abscissa and the pressure in mbar on the ordinate. The pressure inside the container at time t = 0 corresponds to the ambient pressure. When the vacuum pumps are actuated, the pressure inside the container is reduced. The pressure curve over time can be represented as a logarithmic function. Only in the embodiment according to the invention a container pressure of approximately 300 mbar is reached after only 5 seconds, while the comparison devices at this point in time only achieved pressures of approximately 500 to 700 mbar. Already after 15 seconds a pressure of 200 mbar is achieved with the attachment according to the invention, which does not drop much further in the further course. In contrast, the comparison devices only achieve a pressure of around 300 to 400 mbar at this point in time. This clarifies the evacuation performance and the speed of the attachment according to the invention.

Claims

claims:

1. Device for evacuating a storage container for food that can be closed by a valve, with a vacuum pump that can be driven by a rotational movement, characterized in that the device is designed as an attachment (1) for a hand-held electrical household appliance, in particular a hand mixer or hand mixer, and a shaft coupling (7), which can be connected to the drive shaft of the household appliance and with which the vacuum pump (17) can be actuated.

2. Apparatus according to claim 1, characterized in that the vacuum pump (17) is designed as a vane pump which consists of a rotor (10) on which outwardly against the inner wall of a graphite ring (16) movable fins (11) are formed.

3. Apparatus according to claim 1 or 2, characterized in that the attachment (1) has at its suction end a peripheral sealing lip (13) for attachment to a connection device.

4. Device according to one of the preceding claims, characterized in that the attachment (1) has at its drive-side end a plug-in shaft (6) which can be pushed onto the output-side conical end of a hand-held electrical household appliance.

5. Device according to one of the preceding claims, characterized in that a float region (29) is provided between the vacuum pump (17) and the sealing lip (13) in order to prevent the penetration of liquid into the vacuum pump (17).

6. Device according to claim 2, characterized in that the housing of the vacuum pump (17) is formed from a graphite ring and an upper end plate (18) and a lower end plate (12).

7. The device according to claim 2, characterized in that the rotor (10) of the vacuum pump (17) is made of graphite fibers.

8. The device according to claim 2, characterized in that the fins (11) of the vacuum pump (17) is made of graphite.

9. Device according to one of the preceding claims, characterized in that the housing (5) of the attachment (1) is made of suitable thermoplastic material.