EP2971976B1 - Extractor hood - Google Patents

Description

The present invention relates to an extractor hood.

In the past, mainly extractor motors in the form of asynchronous motors were used in extractor hoods due to their inexpensive construction. The asynchronous motors are usually designed as capacitors or split motors. The power control takes place via winding taps or a phase control. In such asynchronous motors, the torque-speed characteristic curve is predetermined by its design and can therefore only be changed to a limited extent.

Extractor hoods can be used in kitchens as exhaust air or recirculating air units. When used as an extractor device, the extractor hood is connected to the customer's piping, which leads the filtered air from the extractor hood out of the kitchen. In the recirculation mode, on the other hand, the extractor hood is directly connected to the air volume of the interior of the kitchen, without any piping. Depending on whether there is piping or how it is designed, there is an individual system characteristic for each extractor hood. An intersection of the system characteristic with a delivery volume-pressure difference characteristic of the extractor hood results in the operating point of the extractor hood. The operating point means the delivery volume and the pressure difference which is established during the operation of the extractor hood. The delivery volume-pressure difference curve is in a fixed relationship with the torque-speed curve of the asynchronous motor. Since the torque-speed characteristic curve of an asynchronous motor is now specified, the delivery volume-pressure difference characteristic curve of the extractor hood is also specified accordingly.

WO 2005/108874 A1 describes a kitchen ventilation system with a fan that has a positive pressure-to-output characteristic.

DE 10 2005 045 137 A1 describes a fan unit with a predetermined artificial characteristic curve and a method for its operation. The fan unit has an electric motor for driving a fan wheel and a motor controller.

US 2011/0000652 A1 describes a ventilation device and associated electronic equipment.

US 2005/0224069 A1 describes a kitchen ventilation system that includes a sensor for detecting a chemical composition over an active zone of a hotplate.

WO 03/050453 A1 describes a work station for moving laboratory animals from one cage to another, the work station comprising an air flow controller. This document discloses all the features of the preamble of claim 1.

JP 2007 100574 A describes a blower that is operated with a constant air volume, wherein an electric current is supplied to an inverter and a rotational speed is detected by a detection device.

It is an object of the present invention to provide an improved extractor hood.

This object is achieved by the features of the independent claims.

The blower motor is thus designed as an electronically commutated synchronous motor which is operated with direct current. Other names for such motors are BLDC (brushless DC motor) or EC motor (electronically commutated motor). Due to the electronic commutation, the present blower motor has a high degree of flexibility with regard to its control options. In particular, the torque-speed characteristic and thus also the delivery volume-pressure difference characteristic - within certain limits - can be freely selected and adapted. In particular, the control device can have software that the first and second torque-speed characteristic Are defined. The torque-speed characteristic curves can be stored in a memory of the control device. In particular, the torque-speed characteristic curves can be stored in the form of value tables. The control device can be provided, for example, in the form of a computer device, in particular as a microprocessor.

By the fact that the torque-speed characteristic curves have at least one common point, it is meant that the torque-speed count characteristic curves in a first area (in at least one point) an identical torque-speed value pair or an identical curve and in a second Range have a different torque-speed value pair or a different course. The first torque-speed characteristic curve can, for example, be assigned to a normal mode of a first operating level of the extractor hood that can be selected by an operator. The second torque-speed characteristic curve can be assigned to a power mode of the extractor hood in the first operating stage. The power mode can correspond to an operation of the extractor hood in which the delivery volume is increased compared to the normal mode. If, for example, the operator switches on the power mode, the extractor hood has, for example, improved extraction in each of four operating stages compared to a respective normal mode. This can be enough for the customer, who values a very quick cleaning of the kitchen air when cooking or who regularly prepares dishes that generate a lot of vapors. Or, for example, an eco mode is shown by means of the second torque-speed characteristic curve, in which the extractor hood in for example, each of its four operating levels causes less noise than a respective normal mode. For example, a noise-sensitive customer can choose Eco mode.

The proposed extractor hood thus has a high degree of flexibility and, with regard to its delivery volume-pressure difference characteristic, can be individually adapted to customer requirements or other general conditions, for example a system characteristic.

According to one embodiment, the control device is set up to control the blower motor with a fourth torque-speed characteristic curve, the first and the fourth torque-speed characteristic curve having at least one common point. Thus, for example, the first torque-speed characteristic curve can correspond to a normal mode of a first operating stage of the extractor hood. The second torque-speed characteristic curve can correspond to the mentioned power mode of the first operating stage and the fourth torque-speed characteristic curve can correspond to the mentioned eco mode of the first operating stage.

The control device is set up to control the blower motor with a third torque-speed characteristic. The third torque-speed characteristic curve does not have a common point with the first, second and / or fourth torque-speed characteristic curve. The third torque-speed characteristic curve thus corresponds, for example, to a normal mode of a second operating stage of the extractor hood. In other words, for example, the third torque-speed characteristic curve differs from the first torque-speed characteristic curve in that a different torque is made available over the entire speed range.

According to a further embodiment, the first, second, third and / or fourth torque-speed characteristic curve has an asynchronous characteristic. An asynchronous characteristic is characterized by the fact that the torque of the blower motor is reduced and the speed of the blower motor increases accordingly in the event of greater air resistance, that is to say, for example, when the piping is longer at the customer. This effect has the advantage that the extractor hood becomes more stable under pressure. In other words, the control device controls the blower motor in such a way that a Extractor hood and a delivery volume, which may be conveyed through a piping downstream of the extractor hood, remains the same with greater air resistance.

According to a further embodiment, the asynchronous characteristic has a tightening torque, a saddle torque, a tipping torque and / or a nominal speed. The asynchronous characteristic therefore basically corresponds to a torque-speed characteristic curve, which corresponds to the shape of a horizontal "S". In other words, the asynchronous characteristic of the torque-speed characteristic curve comprises a valley, which is followed by a mountain in the direction of increasing speed. As the nominal speed increases, the torque drops asymptotically towards zero.

According to a further embodiment, the first, second and / or fourth torque-speed characteristic curve have the same tightening torque, the same saddle torque and / or the same nominal speed and a different breakdown torque. The second and fourth torque-speed characteristic curve therefore deviate, at least in sections, from the first torque-speed characteristic curve in the region of the tilting moment. In the working range of the blower motor, which extends from shortly before the overturning torque to the nominal speed, the first, second and fourth torque-speed characteristic curve have a different profile.

According to a further embodiment, the first and third torque-speed characteristics differ from one another in terms of their tightening torque and / or saddle torque. The first torque-speed characteristic can be assigned to a normal mode of a first operating level and the third torque-speed characteristic can be assigned to a normal mode of a second operating level of the extractor hood. It may be desirable for the customer that the blower motor in the first and second operating stages has different behavior over the entire speed range.

According to a further embodiment, the third torque-speed characteristic curve is shifted in parallel with respect to the first torque-speed characteristic curve. This gives, for example, comparable torque-speed behavior in the first and second operating stages of the extractor hood, but with a different amount of torque.

According to a further embodiment, when the extractor hood of the first torque-speed characteristic is used as intended, a first delivery volume-pressure difference characteristic is the second torque-speed characteristic curve is assigned a second delivery volume-pressure difference characteristic curve, the third torque-speed characteristic curve is a third delivery volume-pressure difference characteristic curve and / or the fourth torque-speed characteristic curve is assigned a fourth delivery volume-pressure difference characteristic curve. The delivery volume is the air volume (including any vapors) which is delivered per unit of time through the extractor hood and any piping connected to it by means of the blower motor. In the present case, the pressure difference means the pressure difference with which the blower motor acts on the air volume. The pressure difference can be measured, for example, between an air outlet of the extractor hood and an environment of the extractor hood. The pressure difference can be measured on the air outlet side as a static pressure difference in a pressure chamber. The delivery volume can be measured using a Venturi nozzle downstream of the pressure chamber. If the blower motor is only activated as a function of, for example, the first torque-speed characteristic curve, depending on an internal resistance of the extractor hood (in recirculation mode) or an additional resistance of a piping connected to the extractor hood (in extract air mode), a delivery volume and a pressure difference arise a. This pair of values corresponds to an operating point of the blower motor which is also referred to here as the operating point. This operating point lies on the first delivery volume-pressure difference characteristic. This working point also corresponds to exactly one pair of values from the first torque-speed characteristic.

According to a further embodiment, the first, second and / or third delivery volume-pressure difference characteristic curve has an at least sectionally convex course and the fourth delivery volume-pressure difference characteristic curve has an at least sectionally concave course. For example, the second delivery volume pressure difference characteristic curve can correspond to a power mode and the fourth delivery volume pressure difference characteristic curve can correspond to an eco mode of the extractor hood. By switching between these two modes, for example based on input from the user or automatically through the extractor hood, the operating point of the extractor hood changes. For example, a system characteristic of the extractor hood can optionally describe the pressure difference depending on the volume flow through the extractor hood and possibly the piping in connection with a piping. This system characteristic curve can have a convex, in particular parabolic, course. By switching between, in particular, the second and fourth delivery volume / speed characteristics of the extractor hood, the working point along the system characteristic postponed. This can, for example, increase the extraction capacity of the extractor hood (power mode), or it can reduce unwanted noise from the extractor hood (eco mode).

According to a further embodiment, the pressure difference of the second delivery volume-pressure difference characteristic curve for each delivery volume is greater than or equal to the pressure difference of the first delivery volume-pressure difference characteristic curve. Additionally or alternatively, the pressure difference of the fourth delivery volume-pressure difference characteristic curve for each delivery volume is less than or equal to the pressure difference of the first delivery volume-pressure difference characteristic curve. The second delivery volume-pressure difference characteristic curve is therefore particularly suitable for representing a power mode of the extractor hood and the fourth delivery volume-pressure difference characteristic curve is particularly suitable for representing an eco mode of the extractor hood.

According to a further embodiment, the third delivery volume-pressure difference characteristic curve is shifted parallel to the first delivery volume-pressure difference characteristic curve. In this way, for example, a boost mode of the extractor hood can be provided.

According to a further embodiment, the control device is set up to control the blower motor as a function of the first or second (or third) torque-speed characteristic as a function of a timer. For example, a temporary boost mode can be provided: For example, this means that the control device first controls the blower motor as a function of the first torque-speed characteristic. After the timer has started, in particular by user input, the control device controls the blower motor with the third (or second) torque-speed characteristic. After a period of time stored on the timer, which can be set in particular by an operator, the control device controls the blower motor again as a function of the first torque-speed characteristic.

According to a further embodiment, the control device is set up to determine whether the extractor hood is in a circulating air or exhaust air mode when used as intended. The control device is also set up, depending on the result of this determination, the blower motor with the first, second or to control the fourth torque-speed characteristic. Tests, in particular by connecting the extractor hood to pipes with different air resistance, can be used to assign either air recirculation or exhaust air operation to the various points on a respective torque-speed characteristic curve. This assignment can, for example, be stored in the form of a table on a memory of the control device. Since the customer knows the torque and speed at all times when using the extractor hood, it can be concluded that the recirculation or exhaust air operation is taking into account the table mentioned. The control device can now also be set up in such a way that it controls the blower motor in the exhaust air mode with the second torque-speed characteristic, which corresponds, for example, to a power mode. In this case, since a larger delivery capacity is required, that is to say if there is a piping, this can be desirable for a customer. Likewise, if recirculation mode is detected, ie there is no piping, the blower motor can be controlled using the fourth torque-speed characteristic curve, that is to say, for example, an eco mode. In recirculation mode, due to the lack of piping, only a lower delivery rate is required in order to extract the hotplate sufficiently.

According to a further embodiment, the control device is set up to recognize, when the extractor hood is used as intended, whether a filter has become saturated or whether there is a blockage in the piping connected to the extractor hood. The control device is further configured to control the blower motor with the first, second or fourth torque-speed characteristic as a function thereof. For example, the control device can be set up to recognize a change in the mentioned working point over time. As described above, the working point is fixed for a specific installation situation and extractor hood. However, this can change over time due to filter saturation or blockage, for example. This can then be recognized by the control device. If, for example, filter saturation is detected, the control device can automatically switch from the first torque-speed characteristic to the second torque-speed characteristic, that is to say, for example, the power mode, in order to compensate for the minus in delivery volume.

The control device is set up to control the blower motor with the first, second, third or a further one as a function of a determined system characteristic Control torque-speed characteristic. This can take into account the fact that in embodiments for different piping, a boost, eco or power mode can be designed differently.

According to a further embodiment, the control device is set up to control the blower motor as a function of a user input with the first, second, third or fourth (or a further) torque-speed characteristic curve. For example, the extractor hood can have an input device for this purpose, in particular in the form of a touchscreen, one or more switches and / or one or more buttons. The user can then select the first, second, third or fourth (or another) torque-speed characteristic as desired. For example, the user can switch between the first and fourth torque-speed characteristic curves, which correspond to a normal mode of a first or second operating stage of the extractor hood. Furthermore, starting from the normal mode, the user can select, for example, a power mode, an eco mode and / or a boost mode from the first operating stage. Furthermore, the extractor hood can have a display device which is set up to indicate whether the control device controls the fan motor with the first, second, third or fourth (or another) torque-speed characteristic. In particular, the display device can be designed as a screen, in particular a TFT screen and / or a touch screen. Furthermore, the display device can be set up to display the current delivery volume flow, for example in the form of cubic meters per hour. As mentioned above, the control device can determine the corresponding values from the current torque and the current speed. Furthermore, the display device can be set up to indicate to the operator whether the extractor hood is in the first, second, third or a further operating stage. In addition, the display device can be set up to indicate whether the extractor hood is in the aforementioned power mode, eco mode or boost mode.

According to a further embodiment, the second and / or third torque-speed characteristic curve is selected to avoid unwanted resonances when the extractor hood is used as intended. Tests, in particular by connecting the extractor hood to different pipes, can be used to determine the torque / speed value pairs for which an unwanted resonance results. If these pairs of values lie, for example, on the first torque-speed characteristic curve, the control device can automatically bypass these unwanted operating points by triggering the blower motor for a specific speed range as a function of the second or third torque-speed characteristic curve. This behavior can also be stored on a memory of the control device.

The extractor hood is preferably designed as a household appliance.

Furthermore, a (further) extractor hood with an electronically commutated fan motor and a control device is provided. The control device is set up to control the blower motor with a first, second or third torque-speed characteristic. The first and third torque-speed characteristic curve can each be selected by an operator using an input device. The control device is also set up to control the blower motor based on a parameter determined by it, starting from the first or third torque-speed characteristic with the second torque-speed characteristic.

In other words, an operator can switch the extractor hood between a first operating level (first torque-speed characteristic curve) and a second operating level (second torque-speed characteristic curve), for example by pressing a button. The control device then automatically switches over from the first torque-speed characteristic to the second torque-speed characteristic in order to take account of certain general conditions, for example a current system characteristic or an operator request for less noise or more delivery volume . The framework condition or the operator's request can each form the parameter determined by the control device. For example, a boost, power or eco mode of the extractor hood can be provided. The operator's request can be conveyed to the control device by an input device of the extractor hood. The first and second torque-speed characteristics can have an asynchronous characteristic and / or be parallel to one another. The third torque-speed characteristic can lie between the first and second torque-speed characteristics and / or be parallel to them. Alternatively, the third torque-speed characteristic curve can have at least one point in common with the first torque-speed characteristic curve and / or an asynchronous characteristic.

The embodiments described for the extractor hood apply accordingly to the further extractor hood, and vice versa.

It should be noted that the terms first, second, etc., torque-speed characteristic curve / delivery volume-pressure difference characteristic curve, etc. are used here. However, this is only for better distinction. It is therefore possible to change the name at any time, for example "fourth" instead of "second".

Furthermore, an extractor hood arrangement with piping and an extractor hood described above is provided. The piping runs, for example, in or on a building. The extractor hood is coupled to the piping in an air-conducting manner.

A method for operating an extractor hood is also provided. In the method, an electronically commutated blower motor with a first or a second torque-speed characteristic curve is controlled by means of a control device, the torque-speed characteristic curves having at least one common point.

A (further) method for operating an extractor hood is also provided. In the method, an electronically commutated blower motor with a first, second or third torque-speed characteristic curve is controlled by means of a control device. The first or third torque-speed characteristic is selected by an operator using an input device. The blower motor is then controlled as a function of a parameter determined by the control device, starting from the selected first or third torque-speed characteristic with the second torque-speed characteristic.

The embodiments described in relation to the extractor hood and the further extractor hood apply accordingly to the present extractor hood arrangement and the present method.

Further possible implementations of the invention also include combinations of features or embodiments of the extractor hoods, the extractor hood arrangement and the methods, which are not explicitly mentioned above or in the following with regard to the exemplary embodiments. The person skilled in the art will also add or change individual aspects as improvements or additions to the respective basic form of the invention.

Further advantageous refinements and aspects of the invention are the subject of the subclaims and the exemplary embodiments of the invention described below. The invention is explained in more detail below on the basis of preferred embodiments with reference to the attached figures.

• Fig. 1: schematisch eine Dunstabzugshaubenanordnung gemäß einer Ausführungsform;
• Fig. 2: Drehmoment-Drehzahl-Kennlinien gemäß einer Ausführungsform;
• Fig. 3: Fördervolumen-Druckdifferenz-Kennlinien sowie Anlagen-Kennlinien gemäß einer Ausführungsform;
• Fig. 4: Fördervolumen-Druckdifferenz-Kennlinien für einen Power- und Eco-Modus gemäß einer Ausführungsform;
• Fig. 5: Fördervolumen-Druckdifferenz-Kennlinien für einen Umluft- und Abluftbetrieb gemäß einer Ausführungsform;
• Fig. 6: Fördervolumen-Druckdifferenz-Kennlinien zur Vermeidung von Resonanz gemäß einer Ausführungsform;
• Fig. 7: Fördervolumen-Druckdifferenz-Kennlinien für einen Boost-Modus gemäß einer Ausführungsform; und
• Fig. 8: Fördervolumen-Druckdifferenz-Kennlinien für einen Boost,- Power- und Eco-Modus gemäß einer weiteren Ausführungsform.

It shows:

• Fig. 1 : schematically, an extractor hood arrangement according to an embodiment;
• Fig. 2 : Torque-speed characteristics according to an embodiment;
• Fig. 3 : Delivery volume-pressure difference characteristics and system characteristics according to an embodiment;
• Fig. 4 : Delivery volume-pressure difference characteristic curves for a power and eco mode according to an embodiment;
• Fig. 5 : Delivery volume-pressure difference characteristics for a recirculation and exhaust air operation according to an embodiment;
• Fig. 6 : Delivery volume-pressure difference characteristics to avoid resonance according to an embodiment;
• Fig. 7 : Delivery volume-pressure difference characteristic curves for a boost mode according to an embodiment; and
• Fig. 8 : Delivery volume-pressure difference characteristics for a boost, - power and eco mode according to a further embodiment.

In the figures, the same reference symbols denote the same or functionally identical components, unless stated otherwise.

Figure 1 schematically shows an extractor hood arrangement 1 according to an embodiment.

The extractor hood arrangement 1 comprises an extractor hood 2, which is arranged above a hotplate 3 in a kitchen. The extractor hood 2 can be designed, for example, as a hood or a chimney. For this purpose, the extractor hood 2 can be fastened to a building wall 5 of the kitchen, just like piping 4. In operation, the extractor hood 2 conveys vapors 6 from above the hotplate 3 via an air inlet 7 to an air outlet 11 thereof. The air outlet 11 is connected via the piping 4 to the environment outside the kitchen in an air-conducting manner. Alternatively, the extractor hood - as will be explained in more detail later - can be provided as a circulating air device, the air outlet 11 being connected to the interior 10 of the kitchen in an air-conducting manner.

The extractor hood 2 comprises a fan wheel 13. The fan wheel 13 will be driven by an electronically commutated fan motor 14. The fan wheel 13 forms, with a spiral-shaped housing 15 surrounding it, a radial blower 16 which sucks the vapors 6 through a grease filter 12 in the region of the air inlet 7 and ejects them through the air outlet 11. The radial blower 16 must overcome the internal air resistance of the extractor hood 2, which arises in particular due to the radial blower 16 itself and an internal piping 17. Furthermore, the radial fan 16 must overcome the air resistance of the piping 4 (if it is present) in order to convey the air outside the interior 10 of the kitchen. The internal air resistance of the extractor hood 2 results in a system characteristic of the same in recirculation mode. The sum of the internal air resistance of the extractor hood 2 and the air resistance of the piping 4 results in the system characteristic in exhaust air mode. Exemplary system characteristics are in Figure 3 shown and designated there with AK1, AK2 and AK3.

Now returning to Figure 1 it is further shown there that the extractor hood 2 comprises a control device 21 which controls the blower motor 14. The control device is designed, for example, as a microprocessor and comprises a memory 22. The memory 22 contains software in the form of Figure 2 torque-speed characteristics shown.

Figure 2 shows a first torque-speed characteristic curve DK1, a second torque-speed characteristic curve DK1a, a third torque-speed characteristic curve DK1b, a fourth torque-speed characteristic curve DK2, and a fifth torque-speed characteristic curve DK3. The torque M of the blower motor 14 is shown as a function of its speed n.

The torque-speed characteristic curves DK1 to DK3 each have an asynchronous characteristic. That means their shape corresponds to a lying "S". This also means that each of the torque-speed characteristic curves DK1 to DK3 has a tightening torque M _A1 , M _A2 , M _A3 , a saddle torque M _S1 , M _S2 , M _S3 , a tipping moment M _K1 , M _K1a , M _K1b , M _K2 , M _K3 and a nominal speed n _N comprises. The tightening torque M _A1 , M _A2 , M _A3 corresponds to the torque of the blower motor 14 at a speed n = 0. Starting from the tightening torque M _A1 , M _A2 , M _A3 , the torque drops to the saddle torque M _S1 , M _S2 , M _S3 with increasing speed n and then rises again, and reaches its maximum M _K1 , M _K1a , M _K1b , M _K2 , M _K3 . Thereafter, the torque M drops again and approaches the nominal speed n _N asymptotically towards zero. A work area in which the blower motor 14 is typically controlled by the control device 21 when the extractor hood 2 is in operation is designated by AH.

The torque-speed characteristic curves DK1, DK1a, DK1b have an identical section in sections. The tightening and saddle torque M _A1 , M _S1 for the torque-speed characteristic curves DK1 to DK1b are identical. _They differ only in terms of their tilting moment M _K1 , M _K1a and M _K1b . This is the tilting moment M _K1a over the _overturning moment M _K1 and the _overturning moment M _K1b under the _overturning moment M _K1 . The torque-speed characteristic curve DK2, on the other hand, runs parallel to the torque-speed characteristic curve DK1 and is shifted upward with respect to this, that is to say consistently characterized by a higher torque M. As a result, the _overturning moment M _K2 lies above M _K1a , M _K1 and M _K1b . The torque-speed characteristic curve DK3 also runs parallel to the torque-speed characteristic curve DK1 and between it and the torque-speed characteristic curve DK2.

The torque-speed characteristic curve DK1 is assigned, for example, to a normal mode of a first operating level of the extractor hood 2 and the torque-speed characteristic curve DK2 to a normal mode of a second operating level of the extractor hood 2. Further operating stages, for example a third and a fourth operating stage, which are shown in Figure 1 are shown. Of course, an off-state of the extractor hood or of the blower motor 14 is also provided. For example, the extractor hood 2, as in Figure 1 shown, comprise buttons 23, by means of which the off state "0" and the first to fourth operating stages "1", "2", "3", "4" can be selected. Depending on a button 23 currently pressed, the control device 21 does not control the blower motor 14 (off state) or with the first torque-speed characteristic curve DK1 (first operating stage) or the fourth torque-speed characteristic curve DK2 (second operating stage) or one another torque-speed characteristic (third and fourth operating level). Instead of the buttons 23, another input device could also be provided.

The second torque-speed characteristic curve DK1a corresponds, for example, to a power mode and the third torque-speed characteristic curve DK1b to an eco mode, as will be explained in more detail below. If the extractor hood 2 is now, for example, in the normal mode (DK1) of the first operating state "1", an operator can remove the extractor hood 2 by pressing an input device, for example in the form of a button 24 from the normal mode in accordance with the first torque-speed Switch the characteristic curve DK1 to the power mode according to the torque-speed characteristic curve DK1a or the eco mode according to the torque-speed characteristic curve DK1b. For example, a switch to power mode can take place if a higher delivery volume flow is desired. Switching to Eco mode can take place if there is noise from the extractor hood 2 should be reduced or energy saved. The switchover to the eco and power mode can also take place when the extractor hood 2 is operated in the normal mode of the second, third or fourth operating stage "2""3""4". The torque-speed characteristic curves DK2a and DK2b exemplify the power or eco mode assigned to the second operating stage "2". The tilting moment M _K2a is then above the tilting moment M _K2 and the tilting moment M _K2b below the tilting moment M _K2 .

Furthermore, the extractor hood 2 can comprise a display device, for example in the form of a TFT screen 25, on which it is displayed in which operating stage the extractor hood 2 is located. Furthermore, the TFT screen 25 can display whether the extractor hood 2 is in the normal mode, power mode or the eco mode. Still further, the TFT screen 25 can display a delivery volume currently being conveyed by the extractor hood 2, for example in cubic meters per hour. The TFT screen 25 can be controlled accordingly by the control device 21. The input devices 23, 24 could also be integrated in the display device 25, for example by being designed as a touchscreen, which is also an input device for user commands.

The following is based on Figure 3 the relationship between a pressure difference p and a delivery volume Q for different system characteristics AK1 to AK3 and different delivery volume-pressure difference characteristics FK1 to FK4 is explained in more detail.

Figure 3 shows the pressure difference p as a function of the delivery volume Q. The pressure difference p denotes a pressure difference between the ambient pressure in the kitchen interior 10 (see Figure 1 ) and a pressure, which is measured, for example, in the air outlet 11 of the extractor hood 2. The delivery volume Q means an air volume delivered per unit of time, for example in cubic meters per hour.

Each of the torque-speed characteristics Figure 2 is a delivery volume-pressure difference characteristic in Figure 3 assigned. For example, the torque-speed characteristic curve DK1 corresponds to the delivery volume-pressure difference characteristic curve FK1 and the torque-speed characteristic curve DK2 corresponds to the delivery volume-pressure difference characteristic curve FK2. The corresponding to the delivery volume-pressure difference characteristic curves FK3 and FK4 Torque-speed characteristics are in Figure 2 Not shown. Each pair of values of a respective torque-speed characteristic curve Figure 2 has a correspondence on a respective delivery volume-pressure difference characteristic Figure 3 .

wobei sich der Parameter a für die Anlagen-Kennlinien AK1 bis AK3 unterscheidet und eine Funktion des Luftwiderstands der Dunstabzugshaube 2 und/oder der Verrohrung 4 ist.If the extractor hood 2 is now operated, for example, as a recirculating air device and the first operating stage "1" in normal mode and thus the first delivery volume-pressure difference characteristic curve FK1 is selected by means of a button 23, an operating point AP1 results at which the extractor hood 2 operates. The operating point AP1 is an intersection between the delivery volume-pressure difference characteristic curve FK1 and the system characteristic curve AK1. The shape of the system characteristic curves AK1 to AK3 corresponds to a parabola, which is characterized by the following equation: $$\mathrm{p}=\mathrm{a}\cdot {\mathrm{Q}}^{\mathrm{2nd}},$$

the parameter a for the system characteristics AK1 to AK3 differs and is a function of the air resistance of the extractor hood 2 and / or the piping 4.

For example, the system characteristic curve AK2 can represent piping 4 with a first length and the system characteristic curve AK3 can represent piping 4 with a second length, the second length being greater than the first length and, accordingly, the air resistance being higher. The operating points AP1, AP2, AP3 and AP4 result from switching between the operating levels "1" to "4" in normal mode, see Figure 2 .

It can be provided that in particular the Figure 3 and 4th The delivery volume-pressure difference characteristic curves FK1 to FK4 are stored, for example in the form of a table, in the memory 22 of the control device 21. Furthermore, torque-speed value pairs M, n assigned to a respective delivery volume-pressure difference value pair p, Q can be stored.

The table can be stored on the memory 22, for example, in a manufacturing process of the extractor hood 2. Before this, the table is generated by using a test extractor hood with different delivery volumes Q and pressure differences p is operated. At the same time, the current torque and the current speed are written to the table. The current torque and the current speed can be read out from the control device 21, for example.

If the extractor hood 2 is now put into operation by the customer, the control device 22 can draw from the current torque M and the current speed n to the delivery volume Q and this, as in FIG Figure 1 shown to show the operator.

Figure 4 now shows a selected delivery volume-pressure difference characteristic curve FK1. It is like in Figure 3 the pressure difference p is plotted as a function of the delivery volume Q. The delivery volume-pressure difference characteristic curve FK1 Figure 4 corresponds to the torque-speed characteristic curve DK1 Figure 2 . A delivery volume-pressure difference characteristic curve FK1a corresponds to the torque-speed characteristic curve DK1a and a delivery volume-pressure difference characteristic curve FK1b corresponds to the torque-speed characteristic curve DK1b. The delivery volume-pressure difference characteristic curve FK1, FK1a and FK1b each have different intersection points with the system characteristic curve AK1 shown by way of example, and accordingly accordingly different pairs of values p, Q. These operating points of the extractor hood 2 are designated AP1, AP1a and AP1b. In Figure 4 it can be seen that the first and second delivery volume-pressure difference characteristics FK1, FK1a have a convex course and the third delivery volume-pressure difference characteristic FK1b has a concave course.

Based on Figure 4 it becomes clear that in the first operating stage "1", switching between normal mode (FK1), power mode (FK1a) and eco mode (FK1b) leads to different delivery volumes Q through the extractor hood 2. At the same time, noise generation and other parameters also differ.

Figure 5 shows further delivery volume-pressure difference characteristics, for example for the extractor hood 2 Figure 1 .

For example, a further torque-speed characteristic curve can be stored in the memory 22 of the control device 21, which is the delivery volume-pressure difference characteristic curve Corresponds to FK1c. Furthermore, the control device 21 can be set up to recognize whether the extractor hood 2 is used in a recirculating air or exhaust air mode. This can be accomplished, for example, by supplementing the above-mentioned table stored in the memory 22 in such a way that certain value pairs p, Q are assigned to a recirculation mode and other value pairs p, Q are assigned to an exhaust mode. The value pairs p, Q can, for example, each be assigned to a value range AB corresponding to an exhaust air mode and a value range UB corresponding to a recirculation mode. The control device 21 can then, for example, automatically decide that in the recirculation mode, the blower motor 14 with the torque-speed characteristic curve DK1 corresponding to the delivery volume-pressure difference characteristic curve FK1, and in the exhaust air operation the blower motor 14 with that corresponding to the delivery volume-pressure difference characteristic curve FK1c Drives torque-speed characteristic (not shown). As a result, the blower motor 14 automatically provides a higher pressure difference p in the exhaust air mode, in which work is to be carried out against a higher air resistance.

In the same way, the control device 21 can make a decision if it shifts the operating points AP1 to AP4 (see Figure 3 ) determines over time that the grease filter 12 or the piping 4 is blocked. Accordingly, the control device 21 can then operate the blower motor 14 in, for example, the first operating stage "1" with the torque-speed characteristic curve corresponding to the delivery volume pressure difference characteristic curve FK1c - instead of the torque-speed characteristic curve DK1 corresponding to the delivery volume pressure difference characteristic curve FK1. control in order to keep the delivery volume Q constant despite the higher air resistance.

Figure 6 now shows the case where APR resonances occur at an operating point. This can be determined, for example, by testing the extractor hood 2 in connection with, for example, different piping 4. It can now be provided that the working point APR is bypassed by changing in sections from the delivery volume-pressure difference characteristic curve FK1 to a delivery volume-pressure difference characteristic curve FK1d. The control device 21 can be set up accordingly. The delivery volume-pressure difference characteristic curve FK1d corresponds to a predetermined torque-speed characteristic curve, which is, however, not shown in any of the figures.

Fig. 7 illustrates the possibility of providing a delivery volume-pressure difference characteristic curve FK1e, which is shifted parallel to the delivery volume-pressure difference characteristic curve FK1, for example in the direction of an increasing pressure difference p and an increasing delivery volume Q. The extractor hood is, for example, in the operating stage "1" (Delivery volume-pressure difference characteristic curve FK1) and the operator presses a boost button 26 of the extractor hood 2, the control device 21 controls the blower motor 14 with one of the in Figure 2 shown torque-speed characteristic curve DK3 corresponding flow volume pressure difference characteristic curve FK1e, so that depending on the system characteristic curve AK2 or AK3 there is a significantly higher pressure difference (AK2) or a significantly higher delivery volume (AK3). A possible boost operating point is designated AP1e. In one embodiment, the control device 21 starts the timer 27 by pressing the boost button 26. After a period of time stored in the timer 27 has elapsed, the control device 21 switches back to the delivery volume-pressure difference characteristic curve FK1. The time period can be set adjustable by the operator, for example by means of the touch screen 25.

Fig. 8 shows delivery volume-pressure difference characteristics in particular for a boost, power and eco mode according to a further embodiment.

In addition to the positive boost-delivery volume-pressure difference characteristic curve FK1e Fig. 7 shows Fig. 8 that a negative boost-delivery volume-pressure difference characteristic curve FK1g can also be provided, which is shifted in parallel with respect to the delivery volume-pressure difference characteristic curve FK1g in the direction of lower pressure difference P and lower delivery volume Q.

Based on Fig. 8 it is further illustrated that an eco or power mode can be designed differently for different pipework, ie system characteristics.

The delivery volume-pressure difference characteristic curves FK1f, FK1h correspond to the delivery volume-pressure difference characteristic curves FK1a, FK1b Fig. 4 in that they also have an intersection with the delivery volume-pressure difference characteristic curve FK1. However, the delivery volume-pressure difference characteristic curve corresponding to an Eco mode is FK1h Convex and not concave like the delivery volume-pressure difference characteristic FK1b.

The control device 21 can be set up to operate the blower motor 14 as a function of a user input or automatically, for example as a function of a current system characteristic curve AK2, AK3 that is determined by the control device 21, with one of the delivery volume-pressure difference characteristic curves FK1, FK1e, FK1f, FK1g or FK1h to control the corresponding torque-speed characteristic. The user input and / or the current system characteristic curve AK2, AK3 is provided to the control device 21 as one or more parameters. The control as a function of a current system characteristic curve AK2, AK3 advantageously allows the operating points of the extractor hood 2 to be adapted to any piping 4 that may be provided. If, for example, it is determined that there is a system characteristic curve AK3, the control device 21 can, when the input device 25 detects a customer request for more delivery volume Q, decide that a switchover from the normal mode (FK1) with an operating point AP1-1 to one Power mode (FK1f) with an operating point AP1f-1 produces an insufficient delivery volume Q, and therefore switch to Boost mode (FK1e) with an operating point AP1e, which has a high additional delivery volume Q. If, on the other hand, the control device 21 recognizes that a system characteristic curve AK2 is present, it switches from normal mode (FK1) with an operating point AP1-2 to power mode (FK1f) with an operating point when a customer requests a greater pressure difference p AP1f-2 µm, since a sufficiently high additional pressure difference p is provided here.

Reference symbols used:

1

Range hood arrangement

2nd

Extractor hood

3rd

Hotplate

4th

Piping

5

Building wall

6

Vapors

7

Air intake

10th

Kitchen interior

11

Air outlet

12th

Grease filter

13

Fan wheel

14

Blower motor

15

casing

16

Radial fan

17th

Piping

21

Control device

22

Storage

23

stud

24th

stud

25th

TFT screen

26

stud

27

timer

FROM

Exhaust mode

AH

Workspace

AK1

System characteristic

AK2

System characteristic

AK3

System characteristic

AP1

Operating point

AP1-1

Operating point

AP1-2

Operating point

AP1a

Operating point

AP1b

Operating point

AP1d

Operating point

AP1f-1

Operating point

AP1f-2

Operating point

AP1e

Operating point

AP2

Operating point

AP3

Operating point

AP4

Operating point

APR

Operating point

DK1

Torque-speed characteristic

DK1a

Torque-speed characteristic

DK1b

Torque-speed characteristic

DK2

Torque-speed characteristic

DK3

Torque-speed characteristic

FK1

Flow rate-pressure difference characteristic

FK1a

Flow rate-pressure difference characteristic

FK1b

Flow rate-pressure difference characteristic

FK1c

Flow rate-pressure difference characteristic

FK1d

Flow rate-pressure difference characteristic

FK1e

Flow rate-pressure difference characteristic

FK1f

Flow rate-pressure difference characteristic

FK1g

Flow rate-pressure difference characteristic

FK1h

Flow rate-pressure difference characteristic

FK2

Flow rate-pressure difference characteristic

FK3

Flow rate-pressure difference characteristic

FK4

Flow rate-pressure difference characteristic

M

Torque

M _A1

Tightening torque

M _A2

Tightening torque

M _A3

Tightening torque

M _K1

Overturning moment

M _K1a

Overturning moment

M _K1b

Overturning moment

M _K2

Overturning moment

M _K2a

Overturning moment

M _K2b

Overturning moment

M _S1

Saddle torque

M _S2

Saddle torque

M _S3

Saddle torque

n

rotational speed

n _N

Nominal speed

UB

Recirculation mode

Claims (13)

1. Extractor hood (2) with an electronically commutated fan motor (14) and a control device (21), which is designed to activate the fan motor (14) with a first or a second speed/torque characteristic curve (DK1, DK1a), wherein the speed/torque characteristic curves (DK1, DKa1) have at least one shared point (M_A1, M_S1)

   characterised in that

   the control device (21) is provided as a computing device and has a memory (22) on which the speed/torque characteristic curves (DK1, DK1a) are stored, and

   the control device (21) is designed the fan motor (14) with a third speed/torque characteristic curve (DK2), wherein the third speed/torque characteristic curve (DK2) has no shared point with the first and/or second speed/torque characteristic curve (DK1, DK1a), and wherein the third speed/torque characteristic curve (DK2) is stored on the memory (22),

   wherein the control device is designed to activate the fan motor as a function of a determined system characteristic curve with the first, second or third speed/torque characteristic curve.
2. Extractor hood according to claim 1, characterised in that the control device (21) is designed to activate the fan motor (14) with a fourth speed/torque characteristic curve (DK1b), wherein the first and fourth speed/torque characteristic curves (DK1, DK1b) have at least one shared point (M_A1, M_S1), wherein the fourth speed/torque characteristic curve (DK1b) is stored on the memory (22).
3. Extractor hood according to claim 2, characterised in that the first, second, third and/or fourth speed/torque characteristic curve (DK1, DK1a, DK1b, DK2) has an asynchronous characteristic, wherein the asynchronous characteristic preferably comprises a tightening torque (M_A1, M_A2), a pull-up torque (Msi, M_S2), a pull-out torque (M_K1, M_K1a, M_K1b, M_K2) and/or a nominal speed (nN).
4. Extractor hood according to claim 3, characterised in that the first, second and/or fourth speed/torque characteristic curve (DK1, DK1a, DK1b) have the same tightening torque (M_A1, M_S1) and/or the same nominal speed (n_N) and a different pull-out torque (M_K1, M_K1a, M_K1b.)
5. Extractor hood according to claim 3 or 4, characterised in that the first and third speed/torque characteristic curve (DK1, DK2) differ from one another in respect of their tightening torque (M_A1, M_A2), pull-up torque (M_S1, M_S2), and/or pull-out torque (M_K1, M_K2).
6. Extractor hood according to one of claims 1 - 5, characterised in that the third speed/torque characteristic curve (DK2) is shifted parallel relative to the first speed/torque characteristic curve (DK1).
7. Extractor hood according to one of claims 2- 6, characterised in that with conventional use of the extractor hood (2) the first speed/torque characteristic curve (DK1) is assigned a first delivery volume pressure difference characteristic curve (FK1), the second speed/torque characteristic curve (DK1a) is assigned a second delivery volume pressure difference characteristic curve (FK1a), the third speed/torque characteristic curve (DK2) is assigned a third delivery volume pressure difference characteristic curve (FK2) and/or the fourth speed/torque characteristic curve (DK1b) is assigned a fourth delivery volume pressure difference characteristic curve (FK1b).
8. Extractor hood according to claim 7, characterised in that the first, second and/or third delivery volume pressure difference characteristic curve (FK1, FK1a, FK2) has a convex curve at least in sections and the fourth delivery volume pressure difference characteristic curve (FK1b) has a convex curve at least in sections.
9. Extractor hood according to one of claims 2 - 8, characterised in that the control device (21) is designed to determine whether, during conventional use, the extractor hood (2) is in recirculated-air or exhaust air operation (UB, AB) and to activate the fan motor (14) with the first, second or fourth speed/torque characteristic curve (DK1, DK1a, DK1b) as a function thereof, wherein an assignment, in which various points on a respective speed/torque characteristic curve (DK1, DK1a, DK1b) are either assigned to recirculated air or exhaust air operation, is saved on the memory (22) of the control device (21).
10. Extractor hood according to one of claims 1 - 9, characterised in that the control device (21) is designed to identify, during conventional use of the extractor hood (2), whether a saturation of a filter (12) of the extractor hood (2) has occurred or a blockage of pipework (4) connected to the extractor hood (2) is present, and to activate the fan motor (2) with the first, second or fourth speed/torque characteristic curve (DK1, DK1a, DK1b) as a function thereof.
11. Extractor hood according to one of claims 2 - 10, characterised in that the control device (21) is designed to activate the fan motor as a function of a user input with the first, second, third and/or fourth speed/torque characteristic curve and/or that a display device (25) is provided which is designed to indicate whether the control device (21) activates the fan motor (14) with the first, second, third or fourth speed/torque characteristic curve (DK1, DK1a, DK1b, DK2).
12. Extractor hood arrangement (1) with pipework (4) and an extractor hood (2) according to one of claims 1 - 11, which is coupled in an air-conducting manner with the pipework (4).
13. Method for operating an extractor hood (2) according to one of the preceding claims 1- 11,

    characterised by

    storing a first and a second speed/torque characteristic curve (DK1, DKa1) and a third speed/torque characteristic curve (DK2) in a memory (22) of a control device (21), which is provided as a computing device, wherein the first and second speed/torque characteristic curves (DK1, DK1a, DK2) have a least one shared point, wherein the third speed/torque characteristic curve (DK2) has no shared point with the first and/or second speed/torque characteristic curve (DK1, DK1a), and

    activating an electronically commutated fan motor (14) with the first, the second or the third speed/torque characteristic curve (DK1, DK1a) as a function of a determined system characteristic curve by means of the control device (21).

Images