WO2025057253A1

WO2025057253A1 - System for detecting an accessory inside a household appliance for cooking or heating foodstuffs

Info

Publication number: WO2025057253A1
Application number: PCT/IT2024/050180
Authority: WO
Inventors: Alessandro TOME'; Alessandro BURATTO
Original assignee: De' Longhi Appliances S.R.L.
Priority date: 2023-09-12
Filing date: 2024-09-10
Publication date: 2025-03-20

Abstract

System (10) for detecting an accessory (11) inside a household appliance (12), comprising: a first component (13) of magnetically conductive material, positioned during use externally and in proximity to a compartment (14) of the household appliance (12) where the accessory (11) is placed; a second component (15) of magnetically conductive material, associated during use with the accessory (11) inserted in the compartment (14); a generator (16) configured to generate a magnetic field (M) between the first and second component (13, 15); and a sensor (17) configured to detect the magnetic field (M), wherein the generator (16) and the sensor (17) are positioned externally and in proximity to the compartment (14).

Description

“SYSTEM FOR DETECTING AN ACCESSORY INSIDE A HOUSEHOLD APPLIANCE FOR COOKING OR HEATING FOODSTUFFS”

FIELD OF THE INVENTION The present invention concerns a system for detecting an accessory inside a compartment of a household appliance which does not require having to install a sensor to detect the accessory inside the compartment.

This system can be used for household appliances for cooking or heating foodstuffs, such as air fryers, ovens, grills, stand mixers or other, in which high temperatures are operated inside a cooking chamber where food residues may be present.

BACKGROUND OF THE INVENTION

Kitchen appliances can be equipped with accessories, each dedicated to a particular type of cooking. Since each type of cooking, and therefore accessory, is characterized by different operating parameters, it is necessary to select the correct ones in order to achieve the desired result. For example, in kitchen appliances for cooking or heating foodstuffs, it is possible to select different temperatures, different air speeds, cooking phases, etc., which are normally set by the user; this can lead to a suboptimal or unsafe use of the appliance if the operating parameters set are not consistent with those required by a given accessory and/or the type of cooking or heating selected.

It is therefore desirable to have an accessory detection system that automatically selects an operating program and/or operating parameters depending on the accessory detected. Known solutions have the disadvantage that detecting accessories inside the cooking chamber presents the problem of the high temperatures present and the food residues that are generated during cooking, thus greatly reducing the use of magnets and radio frequency devices and excluding the use of optical sensors.

The most widely used solution at present is mechanical detection through switches; however, this requires the creation of rods, ribs, elongations of the accessory that intercept the switch when the accessory is inserted in the appliance.

Document CN 207768224 U concerns a blender comprising a container connectable to a base and a mixing device disposed in the container, which is brought into rotation thanks to the attractive force generated between a magnet connected thereto and a drive magnet connected to an electric motor. The blender also comprises a reed type position sensor with a foil switch able to close when the first magnet and the second magnet are located in proximity to one another causing the generation of a magnetic field, or with a Hall effect sensor. The solution requires two magnets able to cooperate with each other, one of which is inserted inside the container; therefore it cannot be used inside a heated compartment of a household appliance for cooking or heating foodstuffs.

Document US 2009/084274 Al describes a household appliance such as a whisk or a blender, provided with a safety system suitable to allow the operation of the appliance only when assembled correctly, wherein the safety system comprises a magnet, a sensor and a sliding element associated with a component to be detected able to move toward and away from an intermediate space between the magnet and the sensor, in order to interfere with the magnetic field generated by the magnet. Such a solution requires that the component is in substantially the same space as the magnet and sensor.

Document US 11564532 B2 concerns a blender comprising a base body made of stainless steel and therefore substantially non-magnetic, having a seating in which a container can be inserted which on the bottom is provided with a magnet and a reed type switch able to detect the magnet on the bottom of the container.

The apparatuses described in these documents all concern household appliances that operate cold, or substantially at room temperature, and the solutions provided to detect the respective accessories are not suitable to be used in environments with high temperatures, such as those required for cooking foodstuffs.

There is therefore the need to perfect a system for detecting an accessory inside a heated compartment of a household appliance that can overcome at least one of the disadvantages of the state of the art.

In particular, one purpose of the present invention is to provide a system for detecting an accessory inside a household appliance that can provide at least one sensor located outside the household appliance, which therefore does not require particular installations or arrangements inside the household appliance and is not substantially influenced by what happens inside it.

Another purpose of the present invention is to provide a system for detecting an accessory inside a heated compartment of a household appliance that, since it comprises at least one sensor located outside, can use components that do not have to be suitable, for example, for use at high temperatures, or for contact with food (food contact safety) or dedicated to a particular type of household appliance. Another purpose of the present invention is to perfect an effective and simple method for detecting an accessory inside a heated compartment of a household appliance.

Another purpose of the present invention is to provide a household appliance comprising an effective and simple system for detecting an accessory inside it. The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

In accordance with the above purposes, a system according to the present invention for detecting an accessory inside a household appliance for cooking or heating foodstuffs comprises: a first component of magnetically conductive material, positioned during use externally and in proximity to a compartment where both the accessory and also the foodstuffs to be cooked or heated are placed; a second component of magnetically conductive material, associated during use with the accessory inserted in the compartment; a magnetic field generator, configured to generate a magnetic field able to interact with the first and second component; and a sensor configured to detect the magnetic field, wherein the generator is distinct from and independent of the first and second component, and both the generator and also the sensor are positioned, during use, externally and in proximity to the compartment.

This system can be used in any type of household appliance that provides the insertion of an accessory inside it, and the sensor for detecting the presence of the accessory is positioned outside of the compartment, therefore it is not necessary to provide special housings or other measures inside the compartment in order to accommodate the sensor or parts thereof. This system therefore proves to be particularly advantageous if used in household appliances with accessories located in high temperature zones, such as the cooking chambers of apparatuses for cooking or heating foodstuffs, since the sensor is not affected by these temperatures or by the presence of food residues. This system therefore allows, on the one hand, to continue to use the magnetic sensor even in high temperature conditions, and on the other to use a sensor in a colder environment, thus being able to provide components that are less valuable, less performing from a thermal point of view and therefore less expensive.

In accordance with one aspect of the invention, both the first as well as the second component can be made of a magnetically conductive material, that is, a material able to interact with the magnetic field generated by the magnetic field generator, in particular in order to deviate its field lines and/or confine it to a certain zone, but it is not required that these components themselves be magnets capable of autonomously generating a magnetic field. Preferably, only a magnetic field generator is provided, in particular in the form of a magnet or a coil traversed by current, while the first and the second component are simply able to interact with such magnetic field.

In accordance with one aspect of the invention, both the first and also the second component are conformed in such a way that when the accessory is inserted in the compartment, they cooperate in such a way as to close the lines of the magnetic field generated by the generator and deviate it toward a zone adjacent to the sensor.

According to one aspect of the invention, the first and the second component are made of ferromagnetic material.

According to another aspect of the invention, the sensor is a Reed or Hall effect sensor, or suchlike.

According to another aspect of the invention, the generator is associated with the first component.

According to another aspect of the invention, the first component provides a first central branch and two lateral branches facing, during use, toward the compartment.

According to another aspect of the invention, the lateral branches of the first component are aligned with the sensor.

According to another aspect of the invention, the generator is associated with the lateral branch of the first component located further away from the sensor than the other lateral branch.

According to another aspect of the invention, the distance between the sensor and the generator is comprised between about 2 cm and about 30 cm, and is preferably around 10-15 cm. This distance allows the non-activation of the sensor when the magnetic field is closed between the first component and the generator, that is, when the accessory and the second component are absent.

According to another aspect of the invention, the first component is formed by at least one metal sheet or by a pack of metal plates.

According to another aspect of the invention, the second component comprises at least one metal sheet applicable, during use, on one side of the accessory, or a pack of metal plates.

According to another aspect of the invention, the second component is positioned substantially parallel to the first component, so as to confine the magnetic field between them and converge the flow of the magnetic field toward the first sensor.

When the first component is C-shaped, the second component is parallel to the central branch so that it forms a partly closed loop together with the lateral branches. This loop remains in particular open between the upper edges of the branches of the first component and the second component, since between them there is located at least one wall that delimits the compartment, but the closed portion is sufficient to effectively confine the magnetic field flow and divert it toward the sensor.

The invention also concerns a method for detecting an accessory inside a household appliance, comprising positioning a first component of magnetically conductive material externally and in proximity to a compartment of the household appliance where both the accessory and also the foodstuffs are placed, during use; inserting a second component of magnetically conductive material, associated during use with the accessory, in the compartment; generating a magnetic field able to interact with the first and second component by means of a magnetic field generator distinct from and independent of the first and second component, and detecting the magnetic field by means of a sensor, wherein both the generator and also the sensor are positioned externally and in proximity to the compartment. The invention also concerns a household appliance, internally comprising a compartment and a system for detecting an accessory positioned inside the compartment.

According to another aspect of the invention, the compartment is at least partly made of non-magnetically conductive material. This non-conductive material is provided in the wall of the compartment which the first component and the second component face.

According to another aspect of the invention, the second component faces a wall of the compartment beyond which it is provided to position the first component, the generator and the sensor.

According to another aspect of the invention, the first component, the generator and the sensor are disposed in a space, or in a hollow space, defined between the compartment and a containing body of the household appliance.

DESCRIPTION OF THE DRAWINGS These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 is a schematic three-dimensional view of a system for detecting an accessory inside a household appliance according to the present invention; - fig. 2 is a schematic three-dimensional view of a component made of electromagnetic material;

- fig. 3 is a schematic three-dimensional view of another component made of electromagnetic material;

- fig. 4 is a schematic lateral view of a household appliance and of the system without the accessory positioned in the household appliance;

- fig. 5 is a schematic lateral view of a household appliance and of the system with the accessory positioned in the household appliance;

- fig. 6 is a schematic view of the trend of the magnetic field when the accessory is not positioned in the household appliance; - fig. 7 is a schematic view of the trend of the magnetic field when the accessory is positioned in the household appliance.

We must clarify that the phraseology and terminology used in the present description, as well as the figures in the attached drawings also in relation as to how described, have the sole function of better illustrating and explaining the present invention, their purpose being to provide a non-limiting example of the invention itself, since the scope of protection is defined by the claims.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

DESCRIPTION OF SOME EMBODIMENTS

We will now refer in detail to the possible embodiments of the invention, of which one or more examples are shown in the attached drawings, by way of a nonlimiting illustration. The phraseology and terminology used here is also for the purposes of providing non-limiting examples.

With reference to the attached drawings, see in particular fig. 1, a system 10 for detecting an accessory 11 inside a household appliance 12 for cooking or heating foodstuffs comprises: a first component 13 of magnetically conductive material, positioned during use externally, and in proximity, to a compartment 14 of the appliance 12 where the accessory 11 is placed; a second component 15 of magnetically conductive material, associated, during use, with the accessory 11 inserted in the compartment 14; a generator 16 configured to generate a magnetic circuit or field M able to interact with the first 13 and second component 15; and a sensor 17 for detecting the magnetic field M generated between the first and second component 13, 15.

According to some embodiments, the system 10 consists of four elements, namely the first component 13, the second component 15, the generator 16 and the sensor 17, of which only the second component 15 is located inside the compartment 14.

The sensor 17 is positioned externally and in proximity to the compartment 14 where the accessory 11 is housed.

The sensor 17 is simple and economical to produce and, since it is not located inside the compartment 14 of the appliance 12, it does not need particular properties, for example particular heat resistance or otherwise, since it is located outside the compartment 14 of the appliance 12.

The sensor 17 can for example be a Reed or Hall effect sensor, or suchlike. The generator 16 of the magnetic field M can be for example a coil traversed by current, or a magnet. The generator 16 is in particular configured to generate a magnetic field M regardless of the presence or not of the second component 15 or even of the first component 13. The generator 16 is preferably associated with the first component 13, so as to also be placed outside the compartment 14 of the household appliance 12.

The first component 13, see also figs. 3-5, provides a first central branch 18 and two lateral branches 19 and 20 facing the compartment 14.

According to some embodiments, the first component 13 can be substantially C-shaped.

The lateral branches 19 and 20 of the first component 13 are aligned with the sensor 17.

The generator 16 is associated with the branch 20 located further away from the sensor 17. The distance between the sensor 17 and the generator 16 is such that the generator 16 does not affect the state of the sensor 17 when the second component 15 is not present.

The distance between the sensor 17 and the generator 16 is comprised between about 2 cm and about 30 cm, and is preferably around 10-15 cm. The first component 13 and the sensor 17 can for example be positioned on a support associated with the casing of the household appliance 12.

According to some embodiments, for example shown in figs. 4 and 5, the first component 13, the generator 16 and the sensor 17 can advantageously be disposed in a space 26, that is, in a hollow space, defined between the compartment 14 and a containing body 27 of the household appliance 12.

The first component 13 is formed by at least one metal sheet bent so as to give it the C-shape, or by a pack of metal plates 21 conformed as a C and packed on top of each other, see also fig. 3.

The second component 15 comprises at least one metal sheet applied on one side 22 of the accessory 11, see fig. 5.

In particular, the second component 15, during use, faces a wall 23 of the compartment 14, beyond which the first component 13 is provided.

The second component 15 can comprise a pack of metal sheets 24, see fig. 3. In order to more effectively form the magnetic circuit through the drive of the generator 16, the second component 15 is positioned substantially parallel to the first component 13, in particular to its central branch 18, if C-shaped.

In this way, the magnetic field M generated by the generator 16 is substantially confined in the space between the first component 13 and the second component 15, and is therefore diverted toward the sensor 17.

When the first component 13 is C-shaped, the second component 15 is substantially parallel to the central branch 18, so as to form, together with the lateral branches 19, 20, a partly closed loop, which remains open due to the presence of the wall 23 of the compartment 14. At least the wall 23 that is interposed between the components 13 and 15 is made of non-magnetically conductive material.

Alternatively, the walls of the compartment 14 are made entirely of non- magnetically conductive material. In the situation in which the accessory is not present, see fig. 6, the magnetic field or circuit M is characterized by the first component 13 only, so that the flow lines generated by the generator 16 will tend to close in the vicinity thereof, not finding a path of lower reluctance, since the second component 15 is not present.

The magnetic field M in the zone where the sensor 17 is positioned is therefore below its activation threshold.

Fig. 7 instead shows a situation in which the magnetic field M is above the activation zone of the sensor 17. In the situation in which the accessory 11 is inside the compartment 14, the second component 15 allows to guarantee a re-closing to the magnetic circuit M formed together with the first component 13, generating a path of lower reluctance than that shown in fig. 6.

In this situation, the zone adjacent to the sensor 17 is characterized by a magnetic field M greater than the situation of fig. 6, such as to exceed the threshold necessary for its activation.

From figs. 6 and 7 it can be seen how, if the accessory 11 provided with the second component 15 is present, the sensor 17 is activated, otherwise it is deactivated or remains inactive.

The material the compartment 14 consist of is, as mentioned above, non- magnetically conductive material. If this condition is not met, an alternative is to create a window in the wall 23 of the compartment 14 and cover it with a cover made of non-magnetically conductive material.

It is possible to provide that the sensor 17 is connected to a control unit 25 provided in the household appliance 12. Based on the data detected by the sensor 17 and therefore on the type of accessory 11 detected, it is also possible, for example, to set certain cooking or heating parameters automatically, assuming that the appliance 12 is an apparatus for cooking or heating foodstuffs.

The household appliance 12 can comprise heating means 26, for example in the form of electrical resistances, which can possibly be associated with ventilation devices 27. Although in figs. 4 and 5 these heating 26 and ventilation means 27 are both positioned in correspondence with an upper portion of the appliance 12, depending on the type of appliance 12, their number can be different, and they can also be positioned in different positions with respect to the compartment 14 and not necessarily next to each other. If the household appliance 12 is an air fryer, the compartment 14 substantially corresponds to the cooking chamber in which a container for the foodstuffs is positioned, which can itself define an accessory 11, or contain an accessory 11 inside it.

In the latter case, both a wall of the compartment 14 and also a wall of the container that contains the accessory 11 are disposed between the first component 13 and the second component 15.

According to this solution, the first component 13, the generator 16 and the sensor 17 associated therewith can be disposed in correspondence with a lateral wall or a bottom wall of the compartment 14. Preferably, they are disposed in correspondence with a bottom wall because, since the latter has a larger extension, the components can be disposed and sized in the most appropriate manner.

If the household appliance 12 is an air fryer, the accessory 11 can be a hot air cooking grill, a grill plate, a steam cooking accessory, a mixing member or other. If the accessory 11 is a hot air cooking grill whose presence is detected by the sensor 17, the control unit 25 can set the cooking mode to hot air cooking and adjust the operation of the various components accordingly.

If the accessory 11 is a grill plate whose presence is detected by means of the sensor 17, the control unit 25 can set the cooking mode to grilling and adjust the operation of the various components accordingly.

If the accessory 11 is a steam cooking accessory whose presence is detected by means of the sensor 17, comprising a bowl suitable to contain water, the control unit 25 can set the cooking mode to steam cooking and adjust the operation of the various components accordingly.

The accessory 11 can be a mixing member disposed in the container and configured to couple to drive means and be made to rotate thereby. In this case, the cooking apparatus comprises drive means disposed in correspondence with a lower internal wall of the housing compartment, which are configured to make the mixing member rotate. When the sensor 17 detects the presence of the mixing member, the control unit 25 can set the cooking mode which provides to mix the foodstuffs and adjust the operation of the various components accordingly.

According to other variants, the household appliance 12 can also be a toaster, which is provided with one or more compartments 14 into which to insert respective elements for gripping and supporting the foodstuffs, each defining an accessory.

In this embodiment, the first component 13, the generator 16 and the sensor 17 associated therewith can be disposed in correspondence with a lateral wall 23 of one or several compartments 14.

According to other variants, the household appliance 12 can be an oven, which is provided with at least one compartment 14 defining the cooking chamber, inside which accessories 11 of different types can be disposed, such as baking trays, support grills, cake pans and suchlike, which can be associated with respective second components 15.

In this embodiment, the first component 13, the generator 16 and the sensor 17 associated therewith can be disposed in correspondence with a lateral wall 23 of the compartment 14, or possibly a bottom wall.

The present method for detecting the accessory 11 inside the household appliance 12 therefore provides to position the first component 13 externally and in proximity to the compartment 14 where the accessory 11 is placed; insert the second component 15 associated with the accessory 11 in the compartment 14; generate a magnetic circuit between the first 13 and second component 15 by means of the magnetic field generator 16, and detect the magnetic field M generated between the first 13 and second component 15 by means of the sensor 17 positioned externally and in proximity to the compartment 14.

This system can be used in any type of household appliance that provides the insertion of an accessory inside it. This system proves to be particularly advantageous if used in household appliances with accessories located in high temperature zones, such as the cooking chambers of apparatuses for cooking or heating foodstuffs, since it allows the sensor and the magnetic field generator to be positioned outside the zone of the appliance subject to high temperatures.

This system therefore allows, on the one hand, to continue to use the magnetic sensor even in high temperature conditions, and on the other hand to use the sensor and the magnetic field generator in a colder environment, thus being able to provide less valuable and therefore less expensive components.

It is clear that modifications and/or additions of parts may be made to the system for detecting an accessory inside a household appliance and to the household appliance as described heretofore, without thereby departing from the field and scope of the present invention, as defined by the claims.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art will be able to achieve other equivalent forms of system for detecting an accessory inside a household appliance, having the characteristics as set forth in the claims all coming within their field of protection. In the following claims, the sole purpose of the references in brackets is to facilitate their reading and they must not be considered as restrictive factors with regard to the field of protection defined by the claims.

Claims

1. System (10) for detecting an accessory (11) inside a household appliance (12) for cooking or heating foodstuffs, said system (10) comprising: a first component

(13) of magnetically conductive material, positioned during use externally, and in proximity, to a compartment (14) of said household appliance (12) where said accessory (11) and said foodstuffs are placed; a second component (15) of magnetically conductive material, associated during use with said accessory (11) inserted in said compartment (14); a magnetic field generator (16), configured to generate a magnetic field (M) able to interact with said first and second component (13, 15); and a sensor (17) configured to detect said magnetic field (M), characterized in that said generator (16) is distinct from and independent of said first and second component (13, 15), wherein both said generator (16) and also said sensor (17) are positioned externally, and in proximity, to said compartment

(14).

2. System (10) as in claim 1, characterized in that said sensor (17) is a Reed or

Hall effect sensor, or suchlike.

3. System (10) as in claim 1 or 2, characterized in that said generator (16) is associated with said first component (13).

4. System (10) as in any claim hereinbefore, characterized in that said first component (13) provides a first central branch (18) and two lateral branches (19,

20) facing, during use, toward said compartment (14).

5. System (10) as in claim 4, characterized in that said lateral branches (19, 20) of said first component (13) are aligned with said sensor (17).

6. System (10) as in claim 4 or 5, characterized in that said generator (16) is associated with the lateral branch (20) of said first component (13) located further away from said sensor (17) than the other lateral branch (19).

7. System (10) as in any claim hereinbefore, characterized in that the distance between said sensor (17) and said generator ( 16) is comprised between about 2 cm and about 30 cm, and is preferably around 10-15 cm.

8. System (10) as in any claim hereinbefore, characterized in that said first component (13) is formed by at least one metal sheet or by a pack of metal plates (21).

9. System (10) as in any claim hereinbefore, characterized in that said second component (15) comprises at least one metal sheet applicable during use on one side (22) of said accessory (11), or a pack of metal plates (24).

10. System (10) as in any claim hereinbefore, characterized in that said first component (13) and said second component (15) are made of ferromagnetic material.

11. System (10) as in any claim hereinbefore, characterized in that said second component (15) is positioned substantially parallel to said first component (13).

12. System (10) as in claim 4, or any previous claim from 5 to 11 when it depends on claim 4, characterized in that said second component (15) is positioned parallel to said central branch (18) of said first component (13) in such a way as to form, together with said lateral branches (19, 20), a partly closed loop.

13. Method for detecting an accessory (11) inside a household appliance (12) for cooking or heating foodstuffs, characterized in that it comprises positioning a first component (13) of magnetically conductive material externally and in proximity to a compartment (14) of said household appliance (12) where said accessory (11) and said foodstuffs are placed; inserting a second component (15) of magnetically conductive material, associated during use with said accessory (11), in said compartment (14); generating a magnetic field (M) able to interact with said first and second component (13, 15) by means of a magnetic field generator (16) distinct from and independent of said first and second component (13, 15), and detecting said magnetic field (M) by means of a sensor (17), wherein both said generator (16) and also said sensor (17) are positioned externally and in proximity to said compartment (14).

14. Household appliance (12) for cooking or heating foodstuffs, internally comprising a compartment (14), heating means configured to heat said compartment (14) in order to cook or heat the foodstuffs inside it, and a system (10) for detecting an accessory (11) positioned inside said compartment (14) as in any claim from 1 to 11.

15. Household appliance (12) as in claim 14, characterized in that said compartment (14) is at least partly made of non-magnetically conductive material and said second component (15) faces a wall (23) of said compartment (14) beyond which it is provided to position said first component (13), said generator (16) and said sensor (17).

16. Household appliance (12) as in either claim 14 or 15, characterized in that said first component (13), said generator (16) and said sensor (17) are disposed in a space (26), that is, in a hollow space, defined between said compartment (14) and a containing body (27) of said household appliance (12).