AU2017341426A1

AU2017341426A1 - Anti-overflow device accompanying a cooking appliance

Info

Publication number: AU2017341426A1
Application number: AU2017341426A
Authority: AU
Inventors: Jean-Marie Bourgeois-Jacquet; Chao Ma
Original assignee: SEB SA
Current assignee: SEB SA
Priority date: 2016-10-13
Filing date: 2017-10-09
Publication date: 2019-04-18
Anticipated expiration: 2037-10-09
Also published as: WO2018069622A1; CA3039024A1; CN106264087B; EP3525633B1; CA3039024C; AU2017341426B2; CN106264087A; EP3525633A1

Abstract

The present invention concerns an anti-overflow device accompanying a cooking appliance. The anti-overflow device comprises: a first electrode (10) and a second electrode (20), spaced apart from each other; an insulator (30) with a cavity (31) arranged on an outer surface of the insulator (30). The first electrode (10) is installed inside the insulator (30), and comprises a projecting portion protruding from a bottom wall of the cavity (31). The distance between the cavity wall (31) and an outer surface of the projecting portion of the first electrode (10) gradually increases from the bottom wall of the cavity (31) in a direction extending towards an opening of the cavity (31). The present invention aims to contribute an effective solution to the shortcomings of anti-overflow devices that exist at present, which are characterised by a lack of responsiveness, activation delays and a risk of overflow.

Description

Anti-Overflow Device Accompanying a Cooking Appliance

Technical Field

This invention relates to the field of anti-overflow technology, and more particularly to an antioverflow device accompanying a cooking appliance.

Prior Art

In order to avoid the risk of overflowing food at the time of boiling, currently existing cooking appliances (pressure cookers, soymilk machines, robot cookers, etc.) generally use antioverflow methods. There are 3 methods as follows:

1. By means of 2 anti-overflow electrodes, one positioned on the bottom of a cooking vessel and the other positioned on the lid of a vessel, the two electrodes protruding inside the cooking vessel. When the boiling liquid or foam rises reaching the electrode positioned on the lid, an electric current passes between the two electrodes and the heating element of the appliance turns off or considerably reduces its power, thus avoiding any risk of an overflow;

2. By means of 2 anti-overflow electrodes positioned on the lid of a cooking vessel and projecting inside the vessel.When the boiling liquid or foam rises to the point of reaching the two electrodes, the heating element of the appliance turns off or considerably reduces its power, thus avoiding any risk of overflow;

3. By means of the first anti-overflow electrode and a temperature sensor positioned on the lid of a cooking vessel, a metal wall of the temperature sensor acts as a second antioverflow electrode. The first anti-overflow electrode and the temperature sensor protrude inside the vessel. When the boiling liquid or foam rises to the point of reaching the first electrode and the temperature sensor, the heating element of the appliance turns off or considerably reduces its power, thus avoiding any risk of overflow;

Among the overflow methods described above, the first requires an excellent seal of the bottom of the vessel to avoid any risk of leakage, the requirements are therefore high in terms of manufacturing. Moreover, the electrode protruding from the bottom of the container affects the overall aesthetics of the device and makes cleaning difficult. The second and third methods can avoid this disadvantage. However, when using these three anti-overflow methods, the liquid or foam in the vessel must be at a specific height to contact the electrode to trigger the anti-overflow device. This presents a great risk of delay and overflow. In addition, the circuit formed at the moment the current passes from one electrode to the other via the foam is unstable and unreliable.

Presentation of the Invention

This invention relates to an anti-overflow device accompanying a cooking appliance, and aims to provide a solution to the deficiencies of existing anti-overflow devices, which are characterized by a lack of sensitivity, trigger delays and overflow risks.

In order to achieve this objective, one aspect of this invention is an anti-overflow device comprising a first electrode and a second electrode which are spaced apart from each other; an insulator, a cavity positioned on an outer surface of the insulator, the first electrode is installed inside the insulator, and having a salient portion protruding from a bottom wall of the cavity, the distance between a side wall of the cavity and an outer surface of the salient portion of the first electrode progressively increasing from the bottom wall of the cavity in a direction extending toward the opening of the cavity.

Advantageously, D1 is the distance between an intersection of the bottom wall and of the side wall of the cavity and the outer surface of the salient portion of the first electrode, and A1 is an angle formed by a generatrix of the cavity side wall and an axis of the first electrode, the distance is greater than or equal to 0.1 mm and less than or equal to 10 mm, the angle A1 is greater than or equal to 3° and less than or equal to 80°.

Advantageously, the distance D1 is greater than or equal to 0.7 mm and lower than or equal to 5 mm, and angle A1 is greater than or equal to 10° and lower than or equal to 60°.

Advantageously, D2 is the diameter of the opening of the cavity, the diameter D2 is greater than or equal to 2 mm and lower than or equal to 25 mm.

Advantageously, the diameter D2 is greater than or equal to 4 mm and lower than or equal to 10 mm.

Advantageously, the salient part of the first electrode passes through the bottom wall to protrude from the opening of the cavity.

Advantageously, the second electrode is positioned on the insulator, and comprises at least one stripped portion located on the outer surface of the insulator.

Advantageously, the cavity is located at one end of the insulator, and the second electrode is positioned on a cylindrical side wall of the insulator.

Advantageously, the end of the insulator comprises a flare, the second electrode is above the flare and the cavity is formed inside the flare, the distance between an outer side wall of the flare and the outer surface of the salient portion of the first electrode progressively increasing from the bottom wall of the cavity in the direction extending towards the opening of the cavity.

Advantageously, A2 is the angle formed by a generatrix from the outer side wall of the flare and the axis of the first electrode, the angle A2 is greater than or equal to 3° and less than or equal to 80°.

Advantageously, the angle A2 is greater than or equal to 10° and less than or equal to 60°.

Advantageously, the second electrode is a conductive strip, the salient part of the first electrode passes from the bottom wall constituting a first active anti-overflow element, the stripped portion of the second electrode positioned on the outer surface of the insulator constituting a second active anti-overflow element, D3 is a distance between the free end of the first active anti-overflow element and the lower end of the second active anti-overflow element located closest to the cavity in a longitudinal direction from the first electrode, the distance D3 is greater than or equal to 0.5 mm and less than or equal to 60 mm,

Advantageously, the distance D3 is greater than or equal to 2 mm and less than or equal to 30 mm.

Advantageously, D4 is the distance between the free end of the first active anti-overflow element and the high end of the second active anti-overflow element located farthest from the cavity in a longitudinal direction from the first electrode, the distance D4 is greater than or equal to 1.5 mm and less than or equal to 60 mm.

Advantageously, the distance D4 is greater than or equal to 3 mm and less than or equal to 30 mm.

Advantageously, the anti-overflow device also comprises a third electrode for detecting the temperature, the third electrode is placed on the cylindrical side wall of the insulator, above the second electrode.

Advantageously, D5 is the distance between a lower end of a stripped portion of the third electrode placed on the outer surface of the insulator and the lower end of the stripped portion of the second electrode placed on the outer surface of the insulator, the distance D5 is greater than or equal to 1 mm and less than or equal to 40 mm.

Advantageously, the distance D5 is greater than or equal to 3 mm and less than or equal to 15 mm.

Advantageously, there are several third electrodes, placed in the longitudinal direction of the insulator and spaced away from each other, D6 is the distance between two adjacent third electrodes, the distance D6 is greater than or equal to 1 mm and less than or equal to 40 mm. Advantageously, the distance D6 is greater than or equal to 3 mm and less than or equal to 25 mm.

Advantageously, there is a space between the second electrode and the insulator, D7 is a distance away from the first and second electrode, the distance D7 is greater than or equal to 2 mm and less than or equal to 150 mm.

Advantageously, the distance D7 is greater than or equal to 5 mm and less than or equal to 100 mm.

Another aspect of this invention relates to a cooking appliance comprising a main body covered by a lid and an anti-overflow device as previously described, placed on the inner side of the lid.

In accordance with the technical solution proposed by this invention, the cavity is placed on the outer surface of the insulator, the first electrode is installed on the interior of the insulator, and having the salient portion protruding from the bottom wall of the cavity, the distance between the side wall of the cavity and the outer surface of the salient portion of the first electrode, gradually increasing from the bottom wall of the cavity in the direction extending towards the opening of the cavity. When the liquid contained in the cooking appliance begins to boil, a large amount of steam is produced and condenses within the cavity and causes the two electrodes to come into contact. An electrical circuit is then established between the first electrode, the second electrode and the printed circuit of the cooking appliance. As the liquid condenses in the cavity, the amplitude of the resistance between the two electrodes increases or changes abruptly, also causing changes in the voltage and the current in the electrical circuit. A control system then detects changes in the internal electrical signals to the circuit and triggers the anti-overflow device by cutting off the heating element of the device, thereby preventing any risk of overflow. The anti-overflow system described above is more sensitive and reliable because it detects boiling at an earlier stage and cuts off the heating element before the surface of the boiling liquid has begun to rise or to produce a large amount of foam. In this way, the risk of overflow is reduced considerably. In addition, the fact that the electrical circuit between the two electrodes is established by the steam and the condensed liquid makes it more stable than in current devices, where the circuit is established by the foam.

Brief Description of the Attached Drawings

The accompanying drawings which constitute an integral part of this application provide a better understanding of this invention, the schematic embodiments of this invention and their explanations is intended to explain this invention without necessarily constituting an inappropriate restriction of this invention. In the attached drawings:

- Figure 1 is a structural view according to a first particular embodiment of the antioverflow device which is the subject-matter of this invention.

- Figure 2 is a cross-sectional view of the anti-overflow device of Figure 1;

- Figure 3 is a cross-sectional view from another angle of the anti-overflow device of Figure 1;

- Figure 4 is a view indicating the dimensions of the anti-overflow device of Figure 2;

- Figure 5 is a view indicating the angles of the anti-overflow device of Figure 2;

- Figure 6 is a structural view according to a second particular embodiment of the antioverflow device which is the subject-matter of this invention.

- Figure 7 is a structural view according to a second particular embodiment of the antioverflow device which is the subject-matter of this invention.

- Figure 8 is a structural view according to one embodiment of the cooking appliance which is the subject-matter of this invention.

The following numbers correspond to the figures appended hereto:

10: the first electrode; 20: the second electrode; 30: the insulator; 31: the cavity; 32: the flare; 40: the second electrode; 50: the main body: 51 : the inner bowl; 60: the lid; 71: the first conductive connection; 72: the second conductive connection.

Detailed Description of Embodiments of the Invention

It should be noted that in the absence of incompatibility, the particular embodiments of this application and the characteristics of these particular embodiments can be mutually combined. This invention will be concisely explained below by means of the attached reference drawings combined with the particular embodiments.

The following part describes and explains in detail the techniques of the particular embodiments of this invention by means of diagrams. It should be noted that the list of embodiments is not exhaustive. The particular embodiments are given for illustrative purposes and in no way limit the possibilities of this invention. All other embodiments obtained by a person skilled in the art on the basis of these embodiments fall within the protected scope of this invention, provided that one skilled in the art did not demonstrate Inventive Step.

It should be noted that the technical terms employed herein are intended only to describe concrete embodiments, and not to limit the exemplary embodiments of this application. Unless explicitly stated otherwise, the technical terms used here also include the plural when singular; furthermore, it should also be understood that the use in this explanatory description of the terms comprise and/or include implies that there are characteristics, steps, tasks, components, parts and/or elements constituting them.

Unless otherwise specified, numerals, numerical values, work steps, and arrangements for the individual parts as set forth in these embodiments do not limit the scope of this invention. Finally, for the sake of clarity, it should be noted that the dimensions of the parts shown in the illustrations do not correspond to the actual proportions. Even if the explanations given may appear to be not very detailed with regard to the technical and practical knowledge of professionals in the field concerned, the techniques, methods and equipment are considered as part of the description provided. In the examples here disclosed and explained, all the concrete figures are to be interpreted in an illustrative way and not in a restrictive way. The figures may therefore be different in other embodiments for illustrative purposes. Important comment: similar signs and letters are used from one illustration to another, so once they are defined for one of the figures, they will not be explained for the figures that follow.

It should be noted that in the description of this invention, the relative locations and positions indicated by terms such as front, behind, on, under, left, right, horizontal, vertical, perpendicular, parallel, high, low, are based on the positions as shown in the illustrations and are given for simplification only. Unless otherwise stated, these positional terms in no way indicate, either explicitly or implicitly, that the different parts of the device must have such and such a precisely defined position in relation to each other; these terms of position therefore in no way constitute a restriction on the scope of this invention; the words inner and outer refer to the inside and outside of the form of each part.

In order to facilitate the demonstration, certain spatial indications such as on, above, on the surface of, above, etc., have been used to describe the spatial relationships between different elements or characteristics represented in the illustrations. It is important to understand that spatial indications may mean other positions or locations than those described in the illustrations in a mode of use or handling. For example, if a part shown in an illustration is inverted, the part originally described as is on or above another part or structure will then be described as under or below this part or structure. Thus, an expression like above includes both the meaning of above and below. A part can also be reoriented in another way (for example at a 90° rotation), in which case the spatial indications must be interpreted accordingly.

In addition, it should be noted that words such as first, second only serve to define two corresponding parts and to distinguish them from each other, they have no semantic content and under no circumstances do they restrict the scope of this invention.

As illustrated in Figures 1 to 3, the anti-overflow device of the first particular embodiment is installed in a rice cooker. The anti-overflow device comprises a first electrode 10 and a second electrode 20 having a space between them, as well as an insulator 30, a cavity 31 placed on an outer surface of the insulator 30, the first electrode 10 is installed on the interior of the insulator 30, and comprising a salient portion projecting from a bottom wall of the cavity 31, the distance between the side wall of the cavity 31 and an outer surface of the salient portion of the first electrode 10 progressively increasing from the bottom wall of the cavity 31 in a direction extending toward an opening of the cavity 31.

According to the anti-overflow device of the first particular embodiment, the cavity 31 is placed on the outer surface of the insulator 30, the first electrode 10 is installed on the interior of the insulator 30, and having the salient portion protruding from the bottom wall of the cavity 31, the distance between the side wall of the cavity 31 and an outer surface of the salient portion of the first electrode 10 progressively increasing from the bottom wall of the cavity 31 in a direction extending toward an opening of the cavity 31. When the liquid in the rice cooker begins to boil, a large amount of steam produced condenses in the cavity 31 and puts the two electrodes in contact. An electrical circuit is then established between the first electrode 10, the second electrode 20 and the printed circuit of the rice cooker. As the liquid condenses in the cavity 31, the amplitude of the resistance between the two electrodes increases or changes abruptly, also causing changes in voltage and in the strength of the electrical circuit. A control system then detects changes in the electrical signals internal to the circuit and triggers the antioverflow device by cutting off the heating element of the cooking appliance, thus preventing any risk of overflow. The anti-overflow system described above is more sensitive and reliable because it detects boiling at an earlier stage and cuts off the heating element before the surface of the boiling liquid has begun to rise or to produce a large amount of foam. In this way, the risk of overflow is reduced considerably. In addition, the fact that the electrical circuit between the two electrodes 10,20 is established by the steam and the condensed liquid makes it more stable than in current devices, where the circuit is established by the foam. It should be noted that in this embodiment, the control system of the rice cooker only triggers the antioverflow device under certain conditions. Specifically, the control system triggers the antioverflow device by cutting off the heating element of the rice cooker only when the resistance between the two electrodes 10 and 20 increases to a certain threshold.

As illustrated in Figures 2 and 3, in the anti-overflow device of the first particular embodiment, the salient part of the first electrode 10 passes through the bottom wall to protrude from the opening of the cavity 31. When the heating element is shut off, the condensed liquid in the cavity 31 continues to adhere to the cavity due to the surface tension. If the condensed liquid does not subside, the amplitude of the resistance between the electrodes 10 and 20 cannot return to its original state, which would have the effect of disrupting the operation of the antioverflow device the next time. However, since the salient portion of the first electrode 10 protruding from the bottom wall of the cavity 31 is sufficiently long, the condensed liquid can flow along the salient part of the first electrode 10 and then fall back in the form of drops. In this way, the above problem is solved.

As illustrated in Figures 1 to 3, in the anti-overflow device of the first particular embodiment, the second electrode 20 is positioned on the insulator 30 and comprises at least one stripped portion placed on the outer surface of the insulator 30. In this case, the electrodes 10 and 20 are both installed on the insulator 30. In other words, the anti-overflow device is a single piece. Such a device is at the same time practical, compact and economical in a number of pieces. Of course, the position of the second electrode 20 is not limited to this embodiment, the second electrode can also be installed elsewhere than on the insulator.

As illustrated in Figures 1 to 3, in the anti-overflow device of the first particular embodiment, the cavity 31 is located at one end of the insulator 30, and the second electrode 20 is placed on a cylindrical side wall of the insulator 30. In this embodiment, the first electrode 10 passes through the insulator 30 from one side to the other in a longitudinal direction from the insulator 30, a lower end of the first electrode 10 protrudes from the bottom wall of the cavity 31, an upper end of the first electrode 10 protrudes from an upper end of the insulator 30. The upper end of the first electrode 10 is connected to a first conductive connector 71 which has a first connection hole. The second electrode 20 is a circular metal piece embedded in a lower part of the insulator 30. The insulator 30 has two openings in which a portion of the circular metal piece is stripped. The second electrode 20 is located at a distance from the first electrode 10. Inside the insulator 30 is also installed a second conductive connection 72, which is positioned in the longitudinal direction of the insulator 30. A first end of the second conductive connection 72 is connected to the second electrode 20, while a second end of the second conductive connector 72 protrudes from the upper end of the insulator 30. The second end of the second conductive connector 72 has a second connection hole. Said first and second connecting holes may be connected to the printed circuit of the pressure cooker via a conductive wire.

It should be noted that the shape of the insulator 30 and the structure of the second electrode 20 are not limited to this embodiment. In other non-illustrated embodiments, the insulator may have a shape other than that indicated in the figures, and the second electrode may be a metal part of another shape, or another type of conductor of a different material. In addition, the mode of connection of the electrodes 10 and 20 to the printed circuit is not limited to this embodiment either, in other non-illustrated embodiments, the first and second electrodes 10 and 20 can be directly connected to the printed circuit via conductive wires. On the other hand, in this embodiment, the first electrode 10 is a solid metal rod. But the structure of the first electrode 10 is not limited to this embodiment. In other embodiments, the structure of the first electrode may be a hollow rod comprising an integrated thermistor, in which case the first electrode serves to constitute a temperature sensing element.

As shown in Figure 3, in the anti-overflow device of the first particular embodiment, the end of the insulator 30 comprises a flare 32, the second electrode 20 is located above the flare 32 and the cavity 31 is formed inside the flare 32, the distance between an outer side wall of the flare 32 and an outer surface of the salient portion of the first electrode 10 progressively increasing from the bottom wall of the cavity 31 in a direction extending toward the opening of the cavity 31 (In other words, the end of the insulator is bell-shaped). In this embodiment, the flare 32 and the cavity 31 have a symmetrical structure, the first electrode 10 is placed along the central axis of the insulator 30, a generatrix from the outer side wall of the flare 32 and a generatrix of the side wall of the cavity 31 are straight lines, thus facilitating its manufacture.

It should be noted that the shape and the structure of the flare 32, the cavity 31 and the first electrode 10 are not limited to this embodiment. In other non-illustrated embodiments, the flare and the cavity may have an asymmetrical structure, the first electrode may be spaced away from the central axis of the insulator, the generatrix of the outer side wall of the flare and of the side wall of the cavity may be curvilinear, and the outer side wall of the flare and the side wall of the cavity may be irregular surfaces. However, the indicated dimensional proportions of the flare 32, the cavity 31 and the first electrode 10 make it possible for sufficient liquid condensation to trigger the anti-overflow device.

As illustrated in Figures 2 to 5, in the anti-overflow device of the first particular embodiment, D1 is the distance between the intersection of the bottom wall and the side wall of the cavity 31 and the outer surface of the salient portion of the first electrode 10, and A1 is an angle formed by the generatrix and the side wall of the cavity 31 and an axis of the first electrode 10, the distance D1 is greater than or equal to 0.1 mm and less than or equal to 10 mm, the angle A1 is greater than or equal to 3° and less than or equal to 80°, and D1 is preferably greater than or equal to 0.7 mm and less than or equal to 5 mm, and the angle A1 is greater than or equal to 10° and less than or equal to 60°. The dimensions of D1 and A1 can determine the volume of the cavity 31 surrounding the salient portion of the first electrode 10. If D1 and A1 are too large, the liquid cannot condense in time and in sufficient quantity within the cavity 31, and therefore the electrical resistance does not vary sufficiently and the controller does not receive the electrical signals that can trigger the device. Conversely, if D1 and A1 are too small, once the heating element has been deactivated, the condensed liquid in the cavity 31 will have a tendency to not subside due to the surface tension and therefore, the electrical resistance between the first and second electrodes 10 and 20 will not return to its original state, and the operation of the anti-overflow device will be impaired the next time.

As illustrated in Figures 2 to 5, in the anti-overflow device of the first particular embodiment, D2 is the diameter of the opening of the cavity 31, the diameter D2 is greater than or equal to 2 mm and less than or equal to 25 mm, and preferably the diameter D2 is greater than or equal to 4 mm and less than or equal to 10 mm. D2, D1 and A1 together determine the volume of the cavity 31. If D2 is too large, the condensed liquid in the cavity 31 falls, and therefore the electrical resistance does not vary in a timely manner. Conversely, if D2 is too small, once the heating element has been deactivated, the condensed liquid in the cavity 31 will have a tendency to not subside due to the surface tension and consequently, the electrical resistance between the first and second electrodes 10 and 20 will not return to its original level, and the operation of the anti-overflow device will be impaired the next time.

As illustrated in Figures 2 to 5, in the anti-overflow device of the first particular embodiment, A2 is the angle formed by the generatrix of the outer side wall of the flare 32 and the axis of the first electrode 10, the angle A2 is greater than or equal to 3° and less than or equal to 80° and preferably, the angle A2 is greater than or equal to 10° and less than or equal to 60°. A2 determines the angle of separation of the outer side wall of the flare 32. If A2 is too small, the cavity 31 inside the flare 32 will not have the required shape. Conversely, if A2 is too large, the flare will constitute an obstacle between the first and second electrodes 10 and 20, making it difficult for the current to pass between the first and second electrodes 10 and 20.

As illustrated in Figures 2 to 5, in the anti-overflow device of the first particular embodiment, the salient part of the first electrode 10 passes from the bottom wall constituting a first active anti-overflow element, the stripped portion of the second electrode 20 positioned on the outer surface of the insulator 30 constituting a second active anti-overflow element, D3 is a distance between the free end of the first active anti-overflow element and the lower end of the second active anti-overflow element located closest to the cavity 31 in a longitudinal direction from the first electrode 10, the distance D3 is greater than or equal to 0.5 mm and less than or equal to 60 mm and preferably the distance D3 is greater than or equal to 2 mm and less than or equal to 30 mm. If D3 is too large, the first active anti-overflow element and the second active antioverflow element will be too far from each other, making it difficult for the current to pass between the first and second electrodes 10 and 20. Conversely, if D3 is too small, the first and second active anti-overflow elements will be too close to each other and may be directly in contact.

As illustrated in Figures 2 to 5, in the anti-overflow device of the first particular embodiment, D4 is the distance between the free end of the first active anti-overflow element and the upper end of the second active anti-overflow element located farthest from the cavity 31 in a longitudinal direction from the first electrode 10, the distance D4 is greater than or equal to 1.5 mm and less than or equal to 60 mm and preferably the distance D4 is greater than or equal to 3 mm and less than or equal to 30 mm. D4 and D3 together determine the height of the second active anti-overflow element. If the second active anti-overflow element is too high, the steam will bead easily on contact and the drops will flow along the second active anti-overflow element, influencing the accuracy of the resistance between the first and second electrodes 10 and 20. Conversely, if the second anti-overflow active element is too low, this will influence the stability of the flow of the current between the first and second electrodes 10 and 20.

As illustrated in Figure 6, the main difference between the second particular embodiment and the first particular embodiment is that in the second particular embodiment, the second electrode 20 is spaced apart from the insulator 30. In other words, the anti-overflow device is in several pieces. The second electrode 20 may be a metal part integrated into a lid or a temperature sensor integrated into a pressure cooker. D7 is the distance between the first electrode 10 and the second electrode 20, the distance D7 is greater than or equal to 2 mm and less than or equal to 150 mm, and preferably the distance D7 is greater than or equal to 5 mm and less than or equal to 100 mm. If D7 is too large, the electrodes 10 and 20 will be too far from each other, which will make it difficult for the current to pass between the first and second electrodes 10 and 20. Conversely, if D7 is too small, the electrodes 10 and 20 will be too close to each other, and may come into direct contact. The structure and operating principle of the insulator 30 and the first electrode 10 are identical to those of the first particular embodiment, they will not be discussed here in more detail.

As can be seen in Figure 7, the main difference between the third particular embodiment and the first particular embodiment is that in the third particular embodiment, the anti-overflow device also comprises a third electrode 40 for detecting the temperature, the third electrode 40 is placed on the cylindrical side wall of the insulator 30, above the second electrode 20. In this embodiment, the third electrode 40 has an annular shape, and comprises a third conductive connection. The third electrode 40 contains an integrated thermistor for sensing the temperature of the steam.

As can be seen in Figure 7, in the anti-overflow device of the third particular embodiment, D5 is the distance between the second electrode 20 and the third electrode 40, the distance D5 is greater than or equal to 1 mm and less than or equal to 40 mm, and preferably the distance D5 is greater than or equal to 3 mm and less than or equal to 15 mm. In this embodiment, D5 is the distance between a low end of the stripped portion of the third electrode 40 placed on the outer surface of the insulator 30 and the low end of the stripped portion of the second electrode 20 placed on the outer surface of the insulator 30. The third electrode 40 and the second electrode 20 are not likely to influence their operation reciprocally if they are sufficiently distant from each other.

In the anti-overflow device of the third particular embodiment, there are several third electrodes 40, placed in the longitudinal direction of the insulator 30 and spaced apart from each other, D6 is the distance between two adjacent third electrodes 40, the distance D6 is greater than or equal to 1 mm and less than or equal to 40 mm, and preferably the distance D6 is greater than or equal to 3 mm and less than or equal to 25 mm.

As can be seen in Figure 8, this application also proposes a cooking appliance. One cooking appliance embodiment comprises a main body 50 covered by a lid 60 and an anti-overflow device placed on the inner side of the lid 60. The anti-overflow device is in accordance with the first particular embodiment. In this embodiment, the cooking appliance is a rice cooker whose main body 50 comprises an inner bowl 51. When the lid 60 is closed, the anti-overflow device protrudes inside the inner bowl 51. Of course, the cooking appliance is not limited to a rice cooker. The cooking appliance may be a cooking robot, a soymilk machine, etc.

The embodiments mentioned above constitute only the preferable examples of application of this invention and in no way constitute a restriction of this invention. This invention may, for a person skilled in the art, be subject to all types of changes and modifications. All corrections, similar substitutions, improvements, etc., made to this invention in accordance with the spirit and principles of this invention, fall within the protected scope of this invention.

Claims

Claims

1. Anti-overflow device, characterized in that it comprises:

a first electrode (10) and a second electrode (20), having a space between them, an insulator (30), a cavity (31) placed on an outer surface of the insulator (30), the first electrode (10) is installed inside the insulator (30), and having a salient portion protruding from a bottom wall of the cavity (31), the distance between a side wall of the cavity (31) and an outer surface of the salient portion of the first electrode (10) progressively increasing from the bottom wall of the cavity (31) in a direction extending toward an opening of the cavity (31).
2. Anti-overflow device according to Claim 1, characterized in that D1 is the distance between the intersection of the bottom wall and the side wall of the cavity (31) and the outer surface of the salient portion of the first electrode (10), and A1 is an angle formed by a generatrix of the cavity side wall (31) and an axis of the first electrode (10), the distance D1 is greater than or equal to 0.1 mm and lower than or equal to 10 mm, the angle A1 is greater than or equal to 3° and less than or equal to 80°.
3. Anti-overflow device according to Claim 2, characterized in that the distance D1 is greater than or equal to 0.7 mm and less than or equal to 5 mm, and the angle A1 is greater than or equal to 10° and less than or equal to 60°.
4. Anti-overflow device according to Claim 2, characterized in that D2 is the diameter of the opening of the cavity (31), the diameter D2 is greater than or equal to 2 mm and less than or equal to 25 mm.
5. Anti-overflow device according to Claim 4, characterized in that the diameter D2 is greater than or equal to 4 mm and less than or equal to 10 mm.
6. Anti-overflow device according to Claim 1, characterized in that the salient part of the first electrode (10) passes through the bottom wall to protrude from the opening of the cavity (31).
7. Anti-overflow device according to any one of Claims 1 to 6, characterized in that the second electrode (20) is positioned on the insulator (30), and comprises at least one stripped portion located on the outer surface of the insulator (30).
8. Anti-overflow device according to Claim 7, characterized in that the cavity (31) is located at one end of the insulator (30), and the second electrode (20) is placed on a cylindrical side wall of the insulator (30).
9. Anti-overflow device according to Claim 8, characterized in that the end of the insulator (30) comprises a flare (32), the second electrode (20) lying above the flare (32) and the cavity (31) is formed inside the flare (32), the distance between an outer side wall of the flare (32) and the outer surface of the salient portion of the first electrode (10) progressively increasing from the bottom wall of the cavity (31) in a direction extending toward the opening of the cavity (31).
10. Anti-overflow device according to Claim 9, characterized in that A2 is the angle formed by a generatrix of the outer side wall of the flare (32) and the axis of the first electrode (10), the angle A2 is greater than or equal to 3° and less than or equal to 80°.
11. Anti-overflow device according to Claim 10, characterized in that the angle A2 is greater than or equal to 10° and less than or equal to 60°.
12. Anti-overflow device according to Claim 8, characterized in that the second electrode (20) is a conductive blade the salient part of the first electrode (10) passes from the bottom wall constituting a first active anti-overflow element, the stripped portion of the second electrode (20) positioned on the outer surface of the insulator (30) constituting a second active anti-overflow element, D3 is a distance between the free end of the first active anti-overflow element and the lower end of the second active anti-overflow element located closest to the cavity (31) in a longitudinal direction from the first electrode (10), the distance D3 is greater than or equal to 0.5 mm and less than or equal to 60 mm,
13. Anti-overflow device according to Claim 12, characterized in that the distance D3 is greater than or equal to 2 mm and less than or equal to 30 mm.
14. Anti-overflow device according to Claim 12, characterized in that D4 is a distance between the free end of the first active anti-overflow element and the high end of the second active anti-overflow element located farthest from the cavity (31) in a longitudinal direction from the first electrode (10), the distance D4 is greater than or equal to 1.5 mm and less than or equal to 60 mm.
15. Anti-overflow device according to Claim 14, characterized in that the distance D4 is greater than or equal to 3 mm and less than or equal to 30 mm.
16. Anti-overflow device according to Claim 8, characterized in that also comprises a third electrode (40) for detecting the temperature, the third electrode (40) is placed on the cylindrical side wall of the insulator (30), above the second electrode (20).
17. Anti-overflow device according to Claim 16, characterized in that D5 is a distance between a low end of a stripped portion of the third electrode (40) placed on the outer surface of the insulator (30) and the low end of the stripped portion of the second electrode (20) placed on the outer surface of the insulator (30), the distance D5 is greater than or equal to 1 mm and less than or equal to 40 mm.
18. Anti-overflow device according to Claim 17, characterized in that the distance D5 is greater than or equal to 3 mm and less than or equal to 15 mm.
19. Anti-overflow device according to Claim 17, characterized in that there are a plurality of third electrodes (40), placed in a longitudinal direction of the insulator (30) and spaced away from each other, D6 is the distance between two adjacent third electrodes (40), the distance D6 is greater than or equal to 1 mm and less than or equal to 40 mm.
20. Anti-overflow device according to Claim 19, characterized in that the distance D6 is greater than or equal to 3 mm and less than or equal to 25 mm.
21. Anti-overflow device according to any one of Claims 1 to 6, characterized in that there is a space between the second electrode (20) and the insulator (30), D7 is a distance between the first electrode (10) and the second electrode (20), the distance D7 is greater than or equal to 2 mm and less than or equal to 150 mm.
22. Anti-overflow device according to Claim 21, characterized in that the distance D7 is greater than or equal to 5 mm and less than or equal to 100 mm.
23. Cooking appliance having a main body (50) covered by a lid (60) and an anti-overflow device placed on the inner side of the lid (60), characterized in that the anti-overflow device is in accordance with any one of Claims 1 to 22.

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