Stirring device

Abstract

Stirring device (1), comprising a container (2) for receiving the liquid to be stirred, a magnet (4) arranged below the container (2), driven by an electric motor (3) and set in rotation, by means of whose magnetic field a stirring element (5) within the container (2) can be driven and set in a rotational movement, characterized in that the stirring element (5) arranged in the container (2) is composed of a rubber-metal buffer (6) and a whisk (7) mounted slidingly on the rubber-metal buffer (6), wherein: -the rubber-metal buffer (6) has a plate (8) with a pin (9) arranged centrally on the plate (8), -the plate (8) and the pin (9) are accommodated in a rubber or elastomer material and -a contact surface (12) free of the rubber or elastomer material is present between the rubber-metal buffer (6) and the whisk (7), the friction coefficient of which is lower than that of the rubber or elastomer material.

Description

[0001] The invention relates to a stirring device according to the preamble of claim 1.

[0002] EP 1 808 111 A2 already discloses a stirring device with a rotating magnet that drives a counter-polar magnetized stirring helix arranged within a container. The stirring helix extends directly to the inner wall of the container and is guided along it. In this solution, the stirring helix is ​​attached to a pin rotating on the container bottom, thus requiring an additional component and resulting in a very high manufacturing cost for such a stirring device.

[0003] DE 34 39 654 A1 discloses a non-magnetizable barrel, made, for example, of stainless steel, beneath which a motor-driven magnet is rotatably mounted. Inside the barrel is a plastic-coated ferrite rod that serves as a stirring element, driven by the magnet rotating outside the barrel. A disadvantage of this is that the ferrite rod has a relatively large contact surface on the bottom of the container, which can cause damage to the bottom of the container over its service life.

[0004] WO 2009 / 094705 A1 also discloses a device for stirring, frothing, and optionally heating liquid foodstuffs, which consists of at least two device parts, namely a liquid container containing no electrical machine parts, and a machine part in whose housing a motor for a drive magnet is located. Analogous to the previously cited DE 34 39 654 A1, the magnet is also driven here and moves a magnetic stirrer located within the liquid container. For this purpose, the bottom of the liquid container has a recess in its interior, into which the rotating magnet engages from the outside. Such a solution is disadvantageous in that the bottom has elevations and is therefore difficult to clean, which also creates a risk of deposits and contamination in the area of ​​the recess.

[0005] The invention is based on the object of providing a stirring device which has a simple structure, eliminates the disadvantages of the described prior art and thereby produces an optimal stirring result.

[0006] The invention solves this problem with the features of claim 1. Further embodiments of the invention are the subject of the subclaims.

[0007] A stirring device comprising a container for holding the liquid to be stirred, a magnet arranged beneath the container, driven by an electric motor and set in rotation, by means of whose magnetic field a stirring element can be driven within the container and set in rotation, was further developed according to the invention in such a way that the stirring element arranged in the container is composed of a rubber-metal buffer and a whisk mounted so as to slide on the rubber-metal buffer, wherein the rubber-metal buffer has a plate with a pin arranged centrally on the plate, the plate and the pin are accommodated in a rubber or elastomer material and there is a contact surface between the rubber-metal buffer and the whisk which is free of the rubber or elastomer material and whose friction coefficient is lower than that of the rubber or elastomer material.

[0008] A key advantage of the present invention is that the sliding connection between the rubber-metal buffer and the agitator enables virtually friction-free rotation of the agitator. This is because the contact surface between the rubber-metal buffer and the agitator has a very low coefficient of friction, while the rubber-metal buffer has a layer of rubber or elastomer material on its underside resting on the container bottom. The coefficient of friction of the underside of the rubber-metal buffer is therefore significantly higher than that of the contact surface, which ultimately means that the agitator, driven by the magnetic force of the magnet, can rotate unhindered, while the rubber-metal buffer itself remains stationary on the container bottom. According to the invention, the container bottom of the container is preferably flat and therefore has no elevations or depressions.This makes the inventive solution very easy to manufacture overall. Furthermore, the agitator can be designed according to the specific requirements, thus achieving optimal mixing results. The innovative design of this solution ensures that the agitator can be used particularly effectively and versatilely. Furthermore, the agitator is available in various sizes and can be made from different materials to meet specific application requirements. The ability to integrate ferromagnetic materials into the agitator optimizes the efficiency of the rotational movement transmission. The inventive design also allows for easy cleaning, making the agitator particularly suitable for hygiene-critical applications.The modular design also allows the stirring device to be expanded or adapted as needed, making it attractive for a wide range of industrial and domestic applications. Furthermore, the stirring device according to the invention is characterized by the sophisticated integration of the ferromagnetic elements in the agitator. These elements are positioned to enable optimal interaction with the magnetic field of the magnet located below the container. This not only improves the transmission of the rotational force but also significantly increases the precision and efficiency of the entire stirring process.

[0009] According to a first embodiment of the invention, it is proposed that the whisk be made of a food-safe, chemically resistant plastic or stainless steel. The materials used in the manufacture of the device meet the highest standards overall, particularly with regard to durability and chemical resistance. If the whisk is made of plastic, it can be easily manufactured, for example, by injection molding or customized using a 3D printing process. The special design creates a modular stirring element whose individual parts are freely interchangeable and can thus be adapted to specific requirements. It is therefore understandable that a different whisk design is used for viscous liquids than for very thin liquids.Thanks to this modular design, the stirring device can be expanded in a targeted manner, for example by integrating sensors to monitor the stirring process or by using specially designed whisks for sensitive liquids.

[0010] It's worth mentioning here that the magnet driven by the electric motor is also preferably constructed in a similar way to the stirrer, i.e., it consists of a plastic body into which the magnetic elements are embedded or integrated. This standardization of components greatly simplifies the entire stirring device, making it easier and faster to manufacture. Furthermore, manufacturing costs can be reduced.

[0011] A further development measure involves providing the contact surface between the rubber-metal buffer and the stirrer with a low-friction coating. Such a coating could be polytetrafluoroethylene (PTFE), for example.

[0012] According to a further development of the invention, the agitator is further provided with at least two arms projecting radially from its rotational axis. Such a design of the agitator thus represents a particularly simple variant that can be manufactured cost-effectively and is not complex in terms of manufacturing technology.

[0013] For other applications, it may be useful for the agitator to have several radially projecting arms arranged fan-like around its rotation axis. This achieves particularly good swirling of the liquid in the container and thus further optimizes the stirring result.

[0014] In order to implement the contactless, magnetic drive principle, it is further proposed that at least two ferromagnetic elements arranged opposite one another are integrated into the stirrer, which form the opposite pole to the magnet, as already described at the beginning.

[0015] A further embodiment of the invention provides for the container to be arranged upright on a base containing the electric motor with the magnet. The construction of the base, which houses the electric motor and the magnet, results in an overall very stable and low-vibration stirring device that also meets ergonomic aspects. This innovation is particularly advantageous for applications that require consistent and powerful mixing, for example, in the chemical or pharmaceutical industries or in animal husbandry. The base has been designed to be easily accessible for maintenance work. The combination of sophisticated design and technological sophistication ensures that the stirring device meets the highest requirements.

[0016] Additionally, the integration of sensors for real-time monitoring of the mixing process offers a way to ensure the quality and consistency of the results. This makes the mixing device a universal tool that is indispensable in both professional and home applications.

[0017] The invention is explained in more detail below with reference to the accompanying drawings. The exemplary embodiment shown does not represent a limitation to the variant shown, but merely serves to explain a principle of the invention. Identical or similar components are always designated by the same reference numerals. In order to illustrate the inventive mode of operation, the figures only show highly simplified schematic diagrams, in which components not essential to the invention have been omitted. However, this does not mean that such components are not present in a solution according to the invention.

[0018] It shows: Fig. 1: a sectional view of the entire stirring device and Fig. 2: Partial section through the container bottom and the base located underneath in the area of ​​the drive.

[0019] From the Fig. Figure 1 shows a vertical section through the entire stirring device 1, which initially comprises a container 2, which is placed with its container bottom 17 on a base 16. The base 16 forms a cavity in which an electric motor 3 is housed, which sets a magnet 4 in a rotating motion. Within the container 2, on the container bottom 17, there is also a stirring element 5, which in turn has two ferromagnetic elements 14 and 15 arranged opposite one another as the magnetic counterpole to the magnet 4. The ferromagnetic elements 14 and 15 are components of a rotating whisk 7, which has the ferromagnetic elements 14, 15 in its arms 12, 13 and is thus driven by the rotating magnet 4, thereby itself performing a rotating motion and stirring the liquid located in the interior of the container 2.

[0020] More in detail the Fig. 2 shows a section through the container bottom 17 and the base 16 arranged underneath in the area of ​​the drive, which in this case is formed by an electric motor 3. In the specific embodiment, the electric motor 3 is coupled to the magnet 4 via a shaft (not further designated) and sets the latter in a rotational movement. The magnetic field of the magnet 4 influences ferromagnetic elements 14 and 15 within the stirrer 7, which is arranged on the container bottom 17 and above the magnet 4. The stirrer 7 in turn consists of a rubber-metal buffer 6 and two oppositely arranged arms 12 and 13, in each of which one of the ferromagnetic elements 14 and 15 is embedded. The connection between the rubber-metal buffer 6 and the stirrer 7 is Fig.2, a contact surface 10 is made of a low-friction material, such as metal or Teflon, so that the stirrer 7 can slide easily, i.e., rotate, on the contact surface 10 of the rubber-metal buffer 6. The stirrer 7 is thus movably mounted on the rubber-metal buffer 6. Furthermore, the stirring element 5 has a modular design overall, which allows individual components to be replaced. The rubber-metal buffer 6 further comprises a surface made of a rubber or elastomer material that rests against the container bottom 17 and releasably fixes the stirring element 5 to the container bottom 17 due to the higher friction compared to the contact surface 10 of the rubber-metal buffer 6. The rubber-metal buffer 6 in turn consists of a plate 8, in the center of which a raised pin 9 is arranged, wherein a casing made of a rubber or elastomer material represents the special feature of the rubber-metal buffer 6.Only in the area of ​​the contact surface 10 is the coating of the rubber or elastomer material missing. This design of the rubber-metal buffer 6 enables a simple combination of the individual elements of the modular stirring element 5. LIST OF REFERENCE SYMBOLS: 1 stirring device 2 containers 3 electric motor 4 Magnet 5 stirring element 6 rubber-metal buffers 7 whisks 8 plate 9 pin 10 Contact surface 11 Rotation axis 12 booms 13 booms 14 ferromagnetic element 15 ferromagnetic element 16 sockets 17 Container bottom QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 1 808 111 A2

[0002] DE 34 39 654 A1 [0003, 0004] WO 2009 / 094705 A1

[0004]

Claims

[1] Stirring device (1), comprising a container (2) for receiving the liquid to be stirred, a magnet (4) arranged below the container (2), driven by an electric motor (3) and set in rotation, by means of whose magnetic field a stirring element (5) within the container (2) can be driven and set in a rotational movement, characterized by that the stirring element (5) arranged in the container (2) is composed of a rubber-metal buffer (6) and a whisk (7) slidingly mounted on the rubber-metal buffer (6), wherein: -the rubber-metal buffer (6) has a plate (8) with a pin (9) arranged centrally on the plate (8), -the plate (8) and the pin (9) are accommodated in a rubber or elastomer material and -a contact surface (12) free of the rubber or elastomer material is present between the rubber-metal buffer (6) and the whisk (7), the friction coefficient of which is lower than that of the rubber or elastomer material. [2] Stirring device according to claim 1, characterized by that the whisk (7) is made of a food-safe, chemically resistant plastic or stainless steel. [3] Stirring device according to one of the preceding claims, characterized by that the contact surface has a coating of polytetrafluoroethylene (PTFE) to reduce friction. [4] Stirring device according to one of the preceding claims, characterized by that the whisk (7) has at least two arms (12, 13) projecting radially from its axis of rotation (11). [5] Stirring device according to one of the preceding claims, characterized bythat the whisk (7) has several radially projecting arms (12, 13) arranged fan-like around its rotation axis (9). [6] Stirring device according to one of the preceding claims, characterized by that at least two ferromagnetic elements (14, 15) arranged opposite one another are integrated in the whisk (7), which form the opposite pole to the magnet (4). [7] Stirring device according to one of the preceding claims, characterized by that the container (2) is arranged standing on a base (16) having the electric motor (3) with the magnet (4). [8] Stirring device according to one of the preceding claims, characterized by that the stirring device has sensors for monitoring the liquid contained in the container.

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