EP2971977A1

EP2971977A1 - Extractor hood

Info

Publication number: EP2971977A1
Application number: EP14706032.1A
Authority: EP
Inventors: Heinz Bergmeier; Anna Brossmann; Martin Graw; Michael HEGENDÖRFER; Mattias Holmer; Daniel Metz; Klaus-Heiner Rutsch; Ilka Schneider; Martin Schultz; Martina Ziegler
Original assignee: BSH Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2013-03-11
Filing date: 2014-02-21
Publication date: 2016-01-20
Also published as: CN105209828B; WO2014139778A1; DE102013204141A1; CN105209828A

Abstract

The invention relates to an extractor hood (2) having an electronically commutated fan motor (14), a timer (27) for providing a time signal (t1, t2) and a control device (21), which is configured to activate the fan motor in dependence on the provided time signal (t1, t2) having a first torque-velocity characteristic curve (DK1) or having a second torque-velocity characteristic curve (DK1a, DK1b, DK3).

Description

Hood

The present invention relates to an extractor hood.

In extractor hoods, blower motors in the form of asynchronous motors were mainly used in the past due to their cost-effective design. The asynchronous motors are usually designed as a capacitor or gap motors. The power control is via winding taps or a phase control. In such asynchronous motors, the torque-speed characteristic is predetermined by their design and therefore can only be changed to a limited extent.

Extractor hoods can be used in kitchens as exhaust or recirculation units. When used as an exhaust air device, the hood is connected to a piping at the customer, which leads the filtered from the hood air from the kitchen out. In recirculation mode, on the other hand, the extractor hood is directly connected to the air volume of the kitchen interior, ie without any intermediate circuit of a piping. Depending on whether a piping is present or how this is configured, results for a particular extractor hood an individual system characteristic. An intersection of the system characteristic curve with a delivery volume-pressure difference characteristic curve of the extractor hood results in the operating point of the extractor hood. The operating point means that delivery volume and that pressure difference, which or which sets in the operation of the hood. The delivery volume-pressure difference characteristic is in a fixed relationship with the torque-speed characteristic of the induction motor. When operating an extractor hood, it may happen that the customer briefly, for example, due to increased vapor formation, wants a larger delivery volume. In conventional extractor hoods can now be manually switched to a higher operating level of the hood. An object of the present invention is to provide an improved extractor hood. Accordingly, an extractor hood with an electronically commutated fan motor, a timer for providing a time signal and a control device is proposed. The control device is configured to control the fan motor in response to the provided time signal with a first torque-speed characteristic or with a second torque-speed characteristic.

Advantageously, the torque-rotational speed characteristic of the fan motor and thus a corresponding delivery volume-pressure difference characteristic of the extractor hood is controlled by a timer. An example, manual switching can thus be omitted at least partially.

For example, the first torque-speed curve may be associated with a normal mode of a (first) operator-selectable stage of the cooker hood. The second torque-speed characteristic may be associated with a boost or power mode of the hood in the (first) stage of operation. The boost or power mode can correspond to an operation of the hood in which the delivery volume is increased compared to the normal mode.

The blower motor is thus designed as an electronically commutated synchronous motor, which is operated with direct current. Other designations 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 flexibility in terms of its control options. In particular, the torque-speed characteristic and thus also the delivery volume-pressure difference characteristic - within certain limits - freely selectable and customizable. In particular, the controller may include software that defines the first and second torque-speed characteristics. The torque-speed characteristics may be stored on a memory of the control device. In particular, the torque-speed characteristics 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.

According to one embodiment, the timer has a non-triggered mode in which it is set up to provide the control device with a first time signal. len, and a triggered mode in which it is adapted to provide the controller with a second time signal. When provided first time signal, the control device controls the fan motor with the first torque-speed characteristic. In a provided second time signal, the control device controls the fan motor with the second torque-speed characteristic. A trigger event that switches the timer from the non-triggered mode to the triggered mode may be a user input.

According to a further embodiment, a memory for storing a time period and a first input device for an input of a user is provided. The first input device is configured to switch the timer from the non-triggered mode to the triggered mode. The timer will automatically switch back from the triggered mode to the non-triggered mode after the time has elapsed. For example, if the operator requires a higher extraction capacity, for example because the kitchen air is to be cleaned quickly, or if a dish is being prepared in which a lot of vapor is being produced, the first input device can now be actuated. Thereafter, the controller switches from the first torque-speed curve (normal mode) to the second torque-speed curve (boost or power mode), but only until the stored time on the memory has expired. Without further action by the user, the control device then switches back to the first torque / speed characteristic curve (normal mode) after the expiration of the time period. In another embodiment, in which the second torque-speed characteristic is assigned to the Eco mode, the operator activates the first input device if, for example, he calls a telephone conversation in the middle of the preparation of a dish or in an extractor hood running in normal mode. men or another, in particular short conversation in the kitchen would like to lead. At the end of the conversation, the operator may then continue to cook, and after the period of time has elapsed, the cooker hood will again provide the required extraction power in normal mode. According to a further embodiment, a second input device is provided for an input of a user who is set up to set the time span. The user can thus adjust the time span according to his wishes. According to a further embodiment, the time period is permanently predetermined on a memory. This is preferable for example in low-cost extractor hoods, since then no second input device must be provided.

According to a further embodiment, a third input device is provided for input by a user, which is set up to determine the shape of the second torque-rotational speed characteristic as a function of the input of the user. This allows the user to decide individually whether the second torque-speed curve should correspond, for example, to a boost, power or eco mode of the extractor hood. The third input device can be provided, for example, to display the various modes to the user on a screen so that they can easily select.

According to a further embodiment, the first and second torque-speed characteristics have at least one common point. By this is meant that the torque-speed characteristics in a first area (at least one point) have an identical torque-speed value pair or an identical course and in a second area a different torque-speed-value pair or a different course. Thus, it is not necessary to create a new "stage" for the second torque / rotational speed characteristic, but it is sufficient if the second torque / rotational speed characteristic deviates in sections from the first torque / rotational speed characteristic may correspond to the power mode, if it is at least partially over the first torque-speed characteristic, or the Eco mode, if it is at least partially below the first torque-speed curve.

According to a further embodiment, the first and second torque-rotational speed characteristic do not have a common point. Thereby, a second torque-speed characteristic can be provided, which deviates completely from the first torque-speed characteristic and thereby provides a completely different behavior of the hood. Such a torque-speed characteristic curve may correspond, for example, to the boost mode. In that regard, for example, a positive boost mode in which the second torque-speed curve over the first torque-speed curve, and a negative boost mode is conceivable in which the second torque-speed curve is below the first torque-speed characteristic.

According to a further embodiment, the control device is adapted to additionally control the fan motor with a third torque-speed characteristic. The third torque-speed characteristic has no common point with the first or second torque-speed characteristics. For example, the third torque-speed characteristic may be, for example, a normal mode of a second operating stage of the extractor hood. According to a further embodiment, the first, second and / or third torque-rotational speed characteristic curve has an asynchronous characteristic, wherein the asynchronous characteristic preferably comprises a tightening torque, a caliper torque, a tilting moment and / or a nominal rotational speed. The asynchronous characteristic is characterized in that at a greater air resistance, so for example at a longer tubing at the customer, the torque of the fan motor is reduced and the speed of the fan motor increases accordingly. This effect has the advantage that the extractor hood becomes more pressure-stable. In other words, the control device controls the fan motor in such a way that an air volume conveyed through the extractor hood and a casing connected downstream of any downstream of the extractor hood remains the same with greater air resistance. The asynchronous characteristic thus corresponds in principle to a torque-speed characteristic which corresponds to the shape of a horizontal "S." In other words, the asynchronous characteristic of the torque-speed characteristic comprises a valley which has followed a mountain in the direction of increasing speed As torque approaches the rated speed, the torque decreases asymptotically to zero.

According to a further embodiment, the first and second torque-speed characteristics have the same tightening torque, the same fifth-wheel torque and / or the same rated rotational speed and a different tilting torque. This corresponds to a second torque-speed characteristic which has at least one common point with the first torque-speed characteristic. According to a further embodiment, the first, second and / or third torque-rotational speed characteristic curve differ from each other with respect to their tightening torque, fifth wheel torque and / or overturning moment. This is particularly appropriate in the case that the first torque-speed characteristic a normal mode of a first operating stage, the third torque-speed curve a normal mode of a second operating stage and the second torque-speed characteristic one Boost mode corresponds.

According to a further embodiment, the first, second and / or third torque-rotational speed characteristic are shifted parallel to each other. Thus, the torque-speed characteristics can be easily defined.

According to a further embodiment, when the extractor hood of the first torque / rotational speed characteristic is used as intended, a first delivery volume / pressure difference characteristic, the second torque / speed characteristic a second delivery volume / pressure difference characteristic and / or the third torque / speed characteristic third delivery volume pressure difference characteristic assigned. The delivery volume is the air volume (including any vapor), which per unit time the extractor hood and any associated with this piping by means of the blower motor is promoted. The pressure difference in this case means the pressure difference with which the fan 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 by means of a venturi downstream of the pressure chamber. If the fan motor is driven, for example, with the first torque / speed characteristic curve, depending on an internal resistance of the extractor hood (recirculation mode) or in addition a resistance of the hood connected to the extractor hood (exhaust air operation), a delivery volume and a pressure difference. This value pair corresponds to an operating point of the fan motor referred to herein as an operating point. This operating point is based on the first delivery volume pressure difference characteristic. This operating point also corresponds exactly to a value pair of the first torque-speed characteristic curve. According to a further embodiment, the pressure difference of the second delivery volume-speed characteristic for each delivery volume is greater than or equal to the pressure difference of the first delivery volume-speed characteristic. Additionally or alternatively, the pressure difference of the third delivery volume-speed characteristic for each delivery volume is greater than or equal to the pressure difference of the first and second delivery volume-pressure difference characteristic.

The extractor hood is preferably designed as a household appliance.

Furthermore, a method for operating an extractor hood, in particular the extractor hood described above, is provided. In this case, an electrically commutated fan motor is controlled by a control device as a function of a time signal provided by a timer with a first torque-speed characteristic or with a second torque-speed characteristic. The embodiments and features described with respect to the extractor hood apply mutatis mutandis to the method.

It should be noted that in this case, the terms "first", "second", etc., torque-rotational speed characteristic / delivery-volume-pressure difference characteristic / equipment characteristic, etc. are used. However, this is just a better distinction. A change in the name of, for example, "fourth" instead of "second", is possible at any time if required.

Further possible implementations of the invention also include not explicitly mentioned combinations of features or embodiments of the extractor hood and of the method described above or below with regard to the exemplary embodiments. The skilled person will also add or modify individual aspects as improvements or additions to the respective basic form of the invention. Further advantageous embodiments and aspects of the invention are the subject of the dependent claims and the embodiments of the invention described below. Furthermore, the invention will be explained in more detail by means of preferred embodiments with reference to the attached figures. It shows:

1 shows schematically an extractor hood arrangement according to an embodiment; Fig. 2: torque-speed characteristics according to an embodiment;

FIG. 3: Delivery volume-pressure difference characteristic curves and system characteristics according to an embodiment; FIG. FIG. 4 shows delivery-volume-pressure difference characteristic curves for a power and eco mode according to an embodiment; FIG.

Fig. 5: delivery volume-pressure difference characteristics for a recirculation and exhaust air operation according to an embodiment;

FIG. 6 shows displacement-pressure differential curves for avoiding resonance according to an embodiment; FIG.

FIG. 7 shows delivery-volume-pressure difference characteristics for a boost mode according to an embodiment; FIG. and

FIG. 8: Delivery volume-pressure difference characteristic curves for a boost, power and eco mode according to a further embodiment. FIG. In the figures, the same reference numerals designate the same or functionally identical components, unless stated otherwise.

FIG. 1 schematically shows an extractor hood arrangement 1 according to one embodiment.

The extractor hood assembly 1 comprises an extractor hood 2, which is arranged above a cooking point 3 in a kitchen. The extractor hood 2 may for example be designed as a hood or dining. The extractor hood 2 can this - as well as a casing 4 - be attached to a building wall 5 of the kitchen. During operation, the extractor hood 2 conveys vapor 6 from above the cooking point 3 via an air inlet 7 to an air outlet 11 of the same. The air outlet 1 1 is air-conductively connected via the piping 4 with the environment outside the kitchen. Alternatively, the extractor hood - as will be explained in more detail later - be provided as recirculation unit, wherein the air outlet 1 1 is air-conductively connected to the interior 10 of the kitchen.

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 13 forms with a surrounding spiral housing 15, a radial fan 16, which sucks the vapor 6 through a grease filter 12 in the region of the air inlet 7 and expels through the air outlet 1 1. In this case, the radial fan 16, the internal air resistance of the hood 2, which results in particular due to the radial fan 16 itself and an internal casing 17 overcome. Furthermore, the radial fan 16 must overcome the air resistance of the casing 4 (if present) to convey the air outside the interior 10 of the kitchen. The internal air resistance of the extractor hood 2 gives a system characteristic of the same in the recirculation mode. The sum of the internal air resistance of the extractor hood 2 and the air resistance of the casing 4 gives the system characteristic in the exhaust air operation. Exemplary system characteristic curves are shown in FIG. 3 and designated there by AK1, AK2 and AK3.

Returning now to FIG. 1, there is further shown that the extractor hood 2 comprises a control device 21, which controls the fan motor 14. The control device is embodied, for example, as a microprocessor and comprises a memory 22. The memory 22 stores torque-speed characteristics shown in the form of software in FIG.

Figure 2 shows a first torque-speed curve DK1, a second torque-speed curve DK1 a, a third torque-speed curve DK1 b, a fourth torque-speed curve DK2, and a fifth torque-speed curve DK3 , The torque M of the blower motor 14 is shown as a function of its speed n. The torque-speed characteristics DK1 to DK3 each have an asynchronous characteristic. This means that their shape corresponds to a horizontal "S." This also means that each of the torque-rotational speed characteristics DK1 to DK3 has a tightening torque M _A i, M _A2 , M _A3 , a saddle torque M _S i, M _S 2, M _S 3, a tilting moment M _K i, M _K i _a , M _K Ib, _K 2, M _K 3 and a rated speed n _N. The tightening torque M _A1 , M _A2 , M _A3 corresponds to the torque of the fan motor 14 at a rotational speed n = 0. Starting from the tightening torque M _A1 , M _A2 , M _A3 , the torque decreases as the rotational speed M _S i, M _S 2, M _S 3 increases with increasing rotational speed n and thereafter rises again, and reaches its maximum M _K i, M _K ia, M _K -ib, M _K 2, M _K 3. Thereafter, the torque M decreases again and asymptotically approaches zero towards the rated speed n _N. A work area in which the blower motor 14 is typically controlled by the control device 21 during operation of the extractor hood 2, is designated by AH.

The torque-speed characteristics DK1, DK1 a, DK1 b have a sectionally identical course. Thus, the tightening torque and the saddle torque M _A1 , M _S i are identical for the torque-rotational speed characteristics DK1 to DK1b. Only with respect to their overturning moment M _K i, M _K i _a and M _K ib they differ. Thus, the tilting moment M _K i _{a is} above the tilting moment M _K i and the tilting moment M _K ib below the tilting moment M _K i. On the other hand, the torque-rotational speed characteristic curve DK2 runs parallel to the torque-rotational speed characteristic curve DK1 and is shifted upward with respect to this, that is to say characterized by a higher torque M. Consequently, the overturning moment M _K 2 is above M _K , M and M _K ib- The torque-rotational speed characteristic DK3 also runs parallel to the torque-rotational speed characteristic DK1 and between this and the torque-rotational speed characteristic DK2.

The torque-rotational speed characteristic DK1 is associated, for example, with a normal mode of a first operating stage of the extractor hood 2 and the torque / rotational speed characteristic DK2 is assigned to a normal mode of a second operating stage of the extractor hood 2. It is also possible to provide further operating stages, for example a third and a fourth operating stage, which are shown in FIG. Of course, an off-state of the hood or the blower motor 14 is provided. For example, as shown in FIG. 1, the extractor hood 2 may comprise buttons 23, by means of which the off-state "0" and the first to fourth operating steps "1", "2", "3", "4" are selectable. In response to a currently depressed button 23, the controller 21 does not control the blower motor 14 (off state) or with the first torque-speed characteristic DK1 (first operation stage) or the fourth torque-speed characteristic DK2 (second operation stage) or one another torque / speed characteristic (third and fourth operating stage). Instead of the buttons 23, another input device could also be provided.

The second torque-rotational speed characteristic DK1 a corresponds for example to a power mode and the third torque-rotational speed characteristic DK1 b to an eco mode, as will be explained in more detail below. If, for example, the extractor hood 2 is in the normal mode (DK1) of the first operating state "1", an operator can remove the extractor hood 2 by actuating an input device, for example in the form of a button 24 from the normal mode corresponding to the first torque Switch the speed characteristic DK1 into the power mode according to the torque / speed characteristic DK1 a or the eco mode according to the torque / speed characteristic DK1 b For example, it is possible to switch to the power mode if a higher volume flow is desired Switching to eco mode can be done if you want to reduce the noise generated by the cooker hood 2 or save energy Switching to eco and power mode can also be done when the hood 2 is in normal mode second, third or fourth operating stage "2""3""4" is operated. The torque / rotational speed characteristics DK2a and DK2b illustrate, by way of example, the power or eco mode associated with the second operating stage "2." The _overturning moment M _K2a is then above the _overturning moment M _K 2 and the overturning moment M _K 2b below the overturning moment M _K 2- Furthermore, the hood 2 may include a display device, for example in the form of a TFT screen 25, which is displayed in which operating stage, the hood 2. Further, the TFT screen 25 can indicate whether the hood 2 in the normal Still further, the TFT screen 25 can display a delivery volume currently conveyed by the extractor hood 2, for example in cubic meters per hour The input devices 23, 24 could also be incorporated in the display device 25 may be integrated by this is designed, for example, as a touch screen, which is also input device for user commands.

The relationship between a pressure difference p and a delivery volume Q for different system characteristics AK1 to AK3 as well as different delivery volume-pressure difference characteristic curves FK1 to FK4 will be explained in greater detail below with reference to FIG.

FIG. 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 FIG. 1) and a pressure which is measured, for example, in the air outlet 1 1 of the extractor hood 2. The delivery volume Q means a volume of air delivered per unit time, for example in cubic meters per hour.

Each of the torque-speed characteristics of Figure 2 is associated with a delivery volume pressure difference characteristic in Figure 3. Thus, for example, corresponds to the torque-speed characteristic DK1 of the delivery volume-pressure difference characteristic FK1 and the torque-speed characteristic DK2 of the delivery volume-pressure difference characteristic FK2. The torque-speed characteristics corresponding to the delivery volume-pressure difference characteristics FK3 and FK4 are not shown in FIG. Each pair of values of a respective torque-speed characteristic of Figure 2 has a correspondence on a respective delivery volume-pressure difference characteristic of Figure 3.

If, for example, the extractor hood 2 is operated as a circulating air unit and the first operating level "1" in normal mode and thus the first delivery volume-pressure difference characteristic line FK1 are selected by means of a knob 23, an operating point AP1 results, at which the extractor hood 2 The operating point AP1 is an intersection between the delivery volume-pressure difference characteristic FK1 and the system characteristic AK1 The shape of the system characteristics AK1 to AK3 corresponds to a parabola which is characterized by the following equation: p = a * Q ² . wherein the parameter a for the system characteristics AK1 to AK3 differs and is a function of the aerodynamic resistance of the extractor hood 2 and / or the piping 4.

Thus, for example, the system characteristic curve AK2 represent a casing 4 with a first length and the system characteristic AK3 a casing 4 with a second length, wherein the second length is greater than the first length and, accordingly, the air resistance is higher. The operating points AP1, AP2, AP3 and AP4 result by switching between the operating levels "1" to "4" in the normal mode, see FIG. 2.

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

The table can be stored on the memory 22, for example, in a manufacturing process of the extractor hood 2. Previously, the table is generated by operating a test extractor hood with different delivery volumes Q and pressure differentials p. At the same time, the current torque and the respective current speed are written to the table. The current torque and the current speed can be read out of the control device 21, for example. If the extractor hood 2 is now put into operation at the customer, then the control device 22 can close the delivery volume Q from the current torque M and the current rotational speed n and, as shown in FIG. 1, display this to the operator. FIG. 4 now shows a selected displacement-pressure difference characteristic curve FK1. As in FIG. 3, the pressure difference p is plotted as a function of the delivery volume Q. The delivery volume-pressure difference characteristic curve FK1 from FIG. 4 corresponds to the torque-rotational speed characteristic curve DK1 from FIG. 2. A delivery volume-pressure difference characteristic curve FK1 a corresponds to the torque-rotational speed characteristic DK1 a and a delivery volume pressure difference characteristic FK1 b of the torque-rotational speed characteristic DK1 b. The delivery volume-pressure difference characteristic curve FK1, FK1a and FK1b each have different points of intersection with the system characteristic AK1 shown by way of example, and correspondingly so far in each case different pairs of values p, Q. These operating points of the extractor hood 2 are with AP1, AP1 a and AP1 b denotes. It can be seen in FIG. 4 that the first and second displacement-pressure difference characteristic FK1, FK1a have a convex course and the third displacement-pressure difference characteristic FK1b has a concave profile. It is clear from FIG. 4 that in the first operating stage "1" the switching between the normal mode (FK1), the power mode (FK1a) and the eco mode (FK1b) results in different delivery volumes Q through the extractor hood At the same time, noise generation and other parameters also differ, and FIG. 5 shows further displacement-pressure-difference characteristic curves, for example for the extractor hood 2 from FIG.

For example, can be stored on the memory 22 of the controller 21, a further torque-speed curve, which corresponds to the delivery volume-pressure difference characteristic FK1 c. Furthermore, the control device 21 can be configured to recognize whether the extractor hood 2 is used in a recirculation or exhaust air operation. This can be accomplished, for example, by supplementing the above-mentioned table stored on the memory 22 in that certain value pairs p, Q are assigned to a recirculation mode and other pairs of values p, Q to an exhaust mode. The value pairs p, Q can be assigned, for example, to a value range AB corresponding to an exhaust air operation and to a value range UB corresponding to a recirculation mode. The control device 21 can then automatically decide, for example, that in the exhaust air operation, the fan motor 14 with the torque / rotational speed characteristic DK1 corresponding to the delivery volume / pressure difference characteristic FK1 and the fan motor 14 with the delivery volume / pressure difference characteristic in the recirculation mode FK1 c corresponding torque-speed characteristic (not shown) drives. As a result, the blower motor 14 automatically turns on the recirculation mode, in the house is due to the existing air filter to work against a higher air resistance, a higher pressure difference p ready.

Likewise, the controller 21 may decide, if it detects a shift of the operating points AP1 to AP4 (see FIG. 3) over time, that there is a blockage of the grease filter 12 or the piping 4. Accordingly, the control device 21 then the fan motor 14 in example, the first operating level "1" with the delivery volume-pressure difference characteristic FK1 c corresponding torque-speed curve - instead of the delivery volume-pressure difference curve FK1 corresponding torque-speed curve DK1 - Control to keep the delivery volume Q equal despite the higher air resistance.

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

Fig. 7 illustrates the ability to provide a delivery volume-pressure difference characteristic FK1 e, which is parallel to the delivery volume-pressure difference characteristic FK1 shifted, for example, in the direction of increasing pressure difference p and an increasing delivery volume Q. If the hood is located for example in the Operation level "1" (delivery volume-pressure difference characteristic FK1) and presses the operator person a boost button 26 of the hood 2, the control device 21 controls the fan motor 14 with one of the torque-speed curve shown in Figure 2 DK3 corresponding delivery volume pressure difference Characteristic curve FK1 e, so that a significantly higher pressure difference (AK2) or a significantly higher delivery volume (AK3) results, depending on the system characteristic curve AK2 or AK3 Button 26 is a timer 27 (timer) from an un-triggered mo the same in a triggered mode of the same switched. In non-triggered mode, the timer 27 sets the Control device 21, the blower motor 14, a first time signal ready. When provided time signal t-ι controls the controller 21, the blower motor 14, for example, with the torque-speed characteristic DK1, which corresponds to the delivery volume pressure difference characteristic FK1 and thus the normal mode of the first operating level "1", as already above It may be provided that the timer 27 is automatically in the non-triggered mode when the extractor hood 1 is switched on, that is to say by actuating a button 23 assigned to one of the operating stages "1" to "4" In contrast to the triggered mode, the timer 27 of the control device 21 provides a second time signal t _2. When the time signal t _{2 is provided} , the control device 21 activates the fan motor with the torque / rotational speed characteristic DK3, for example, whereby the corresponding delivery volume / pressure difference characteristic FK1 e which corresponds to the boost mode In the triggered mode, the timer 27 now counts up to a time stored on a memory 28 thereof. When the time span has been reached, the timer has expired and the timer 27 automatically switches back to the non-triggered mode, ie without user interaction. The time span can be, for example, 10 seconds.

The operator button can therefore press the boost button 26 when particularly much vapor is being generated above the hob 3. Then, the hood 2 provides a higher take-off performance and then automatically returns to normal mode. This results in a comfortable operation for the operator.

It can be provided that the operator person can enter the time span on the memory 28 by means of the touchscreen 25 according to individual wishes. In the case of cost-effective extractor hood models, however, provision may be made for the time span to be provided on the memory 28, ie, not changeable, by software technology. Accordingly, then no relatively expensive input device 25 must be provided to allow an adjustment of the period.

Alternatively, it may also be provided that the control device 21 with the second time signal t _{2 provided} the fan motor 14 not with the torque-speed characteristic DK3 corresponding to the boost mode, but with, for example, the torque-speed characteristic DK1 a corresponding to the power mode controls. Thus, the operator person also receives an increased withdrawal rate, but with a different characteristic. Further alternatively, it may be provided that the control device 21 controls the blower motor 14 with the torque-speed characteristic curve DK1 b corresponding to the Eco mode when the second time signal t _{2 is} provided. This reduces the noise level of the extractor hood 2. This makes sense if, for example, the operator person accepts a telephone call in the kitchen or wants to make another, especially short conversation in the kitchen.

Furthermore, it can be provided that the operator person can select the mode, that is, for example, the boost, power or eco mode, via the touchscreen 25 when the second time signal t _{2 is} provided.

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 volume-pressure difference characteristic curve FK1 e from FIG. 7, FIG. 8 shows that a negative boost-volume-pressure difference characteristic FK1 g can also be provided which is opposite to the delivery volume-pressure difference characteristic FK1 g in FIG Direction of lower pressure difference P and lower flow volume Q is shifted in parallel.

With reference to Fig. 8, it is further illustrated that for different casings, i. System characteristics, an eco or power mode can be configured differently. The delivery volume-pressure difference characteristic curves FK1f, FK1h correspond to the delivery volume-pressure difference characteristic curves FK1a, FK1b from FIG. 4 in that they also have an intersection with the delivery volume-pressure difference characteristic FK1. However, the Eco-mode corresponding delivery volume-pressure difference characteristic FK1 h is convex and not concave as the delivery volume-pressure difference characteristic FK1 b.

The control device 21 may be configured to control the blower motor 14 as a function of a user input or automatically, for example as a function of a user input currently present system characteristic AK2, AK3, which is determined by the control device 21, to control with one of the delivery volume-pressure difference characteristics FK1, FK1 e, FK1f, FK1 g or FK1 h 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 activation as a function of a currently present system characteristic curve AK2, AK3 advantageously makes it possible to adapt the operating points of the extractor hood 2 to a possibly provided piping 4. If it is determined, for example, that a system characteristic curve AK3 is present, the control device 21 may decide, when the input device 25 recognizes a customer request for more delivery volume Q, that switching from the normal mode (FK1) to an operating point AP1-1 to a power mode (FK1f) with an operating point AP1f-1 provides too little additional delivery volume Q, and therefore switch to the boost mode (FK1 e) with an operating point AP1 e, which has a high additional delivery volume Q. On the other hand, if the control device 21 recognizes that a system characteristic AK2 is present, it switches to the power mode (FK1f) with an operating point for a customer request for more pressure difference p starting from the normal mode (FK1) with an operating point AP1-2 AP1f-2, since a sufficiently high additional pressure difference p is provided here.

Although the invention has been described herein with reference to preferred embodiments, it is not limited thereto, but variously modifiable.

Used reference signs:

1 extractor hood arrangement

2 extractor hood

3 hob

4 piping

5 building wall

6 vapors

7 air intake

10 kitchen interior

1 1 air outlet

12 grease filters

13 fan wheel

14 blower motor

15 housing

16 radial fans

17 piping

21 control device

22 memory

23 button

24 button

25 TFT screen

26 button

27 timers

28 memory

AB exhaust air operation

AH workspace

AK1 system characteristic

AK2 system characteristic

AK3 system characteristic

AP1 operating point

AP1-1 operating point

AP 1-2 working point AP1 a working point

AP1 b operating point

AP1 d operating point

AP1f-1 operating point

AP1f-2 operating point

AP1 e operating point

AP2 operating point

AP3 operating point

AP4 operating point

APR operating point

DK1 torque-speed characteristic

DK1 a torque-speed characteristic

DK1 b Torque-speed characteristic

DK2 torque-speed characteristic

DK3 torque-speed characteristic

FK1 delivery volume-pressure difference characteristic

FK1 a delivery volume-pressure difference characteristic

FK1 b delivery volume-pressure difference characteristic

FK1 c Displacement-pressure difference characteristic

FK1 d Flow volume-pressure difference characteristic

FK1 e Delivery volume-pressure difference characteristic

FK1f delivery volume-pressure difference characteristic

FK1 g delivery volume-pressure difference characteristic

FK1 h delivery volume-pressure difference characteristic

FK2 delivery volume-pressure difference characteristic

FK3 delivery volume-pressure difference characteristic

FK4 delivery volume-pressure difference characteristic

M torque

M _A i Tightening torque

M _A 2 tightening torque

M _A3 tightening torque

M _K i tilting moment

M _K 1a tilting moment

M _K ib overturning moment M _K2 tilting moment

M _K 2a tilting moment

M _K 2b tilting moment

M _S 1 saddle torque

M _S2 saddle torque

M _S3 fifth wheel torque n speed n _N nominal speed tl time signal t ₂ time signal

UB recirculation mode

Claims

An extractor hood (2) comprising an electronically commutated blower motor (14), a timer (27) for providing a time signal (t _1; t ₂ ) and a control device (21) adapted to operate the blower motor in response to the provided Time signal (t _1; t ₂ ) with a first torque-speed characteristic (DK1) or with a second torque-speed characteristic (DK1 a, DK1 b, DK3) to control.

2. Extractor hood according to claim 1, characterized in that the timer (27) a non-triggered mode in which it is adapted to the control device (21) to provide a first time signal (t-ι), and has a triggered mode, in which it is set up to provide the control device (21) with a second time signal (t ₂ ), and that the control device (21) with the first time signal (t-ι) provided the fan motor (14) with the first torque-speed characteristic (DK1) and when the second time signal (t ₂ ) is provided drives the blower motor (14) with the second torque / rotational speed characteristic (DK1 a, DK1 b, DK3).

An extractor hood according to claim 2, characterized by a memory (28) for storing a period of time and first input means (26) for input of a user adapted to send the timer (27) from the non-triggered mode to the triggered one Switch mode, wherein the timer (27) automatically returns from the triggered mode to the non-triggered mode after the expiration of the time period.

4. Extractor hood according to claim 3, characterized by a second input device (25) for an input of a user, which is adapted to set the time period.

5. Extractor hood according to claim 3, characterized in that the time period on the memory (28) is fixed.

6. Extractor hood according to one of claims 1-5, characterized by a third input device (25) for an input of a user, which is adapted to determine the shape of the second torque-speed characteristic (DK3) in response to an input of the user.

7. Extractor hood according to one of claims 1-6, characterized in that the first and second torque-rotational speed characteristic (DK1, DK1 a, DK1 b) have at least one common point NEN.

8. Extractor hood according to one of claims 1 - 6, characterized in that the first and second torque-speed characteristic (DK1, DK3) have no common point.

9. Extractor hood according to one of claims 1-8, characterized in that the control device (21) is adapted to the blower motor (14) additionally with a third torque-speed characteristic (DK2) to control, and that the third torque speed Characteristic curve (DK2) has no common point with the first and / or second torque / rotational speed characteristic (DK1, DK1a, DK1b, DK3).

10. Extractor hood according to one of claims 1 - 9, characterized in that the first, second and / or third torque-speed characteristic (DK1; DK1a, DK1b, DK3; DK2) has an asynchronous characteristic, the asynchronous characteristic being preferably a tightening torque (M _A1 , M _A3 , M _A2 ), a saddle torque (M _S i, M _S 3, M _S 2), a tilting moment (MK-I, M _K 3, M _K 2) and / or a Nenn Speed (n _N ) includes.

1 1. Extractor hood according to claim 10, characterized in that the first and second torque-rotational speed characteristic (DK1, DK1 a, DK1 b) the same tightening torque (M _A i), the same saddle torque (M _S i) and / or the same rated speed ( n _N ) and a different tilting moment (M _K i, M _K i _a , M _K it _> ) have.

12. Extractor hood according to claim 10, characterized in that the first, second and / or third torque-speed characteristic curve (DK1, DK3, DK2) with respect to their tightening torque (M _A i, M _A 3, M _A2 ), saddle moment ( M _S i, M _S 3, M _S 2) and / or tilting moment (M _K i, M _K 3, MIO) differ from each other.

13. Extractor hood according to one of claims 1 - 12, characterized in that the first, second and / or third torque-speed characteristic (DK1, DK3, DK2) are mutually displaced in parallel.

14. Extractor hood according to one of claims 1 - 13, characterized in that when used according to the extractor hood of the first torque-speed characteristic (DK1) a first displacement-pressure difference characteristic (FK1), the second torque-speed characteristic (DK1 a, DK1 b, DK3) a second delivery volume pressure difference characteristic (FK1 a, FK1 b, FK1 e) and / or the third torque-speed characteristic (DK2) is associated with a third delivery volume pressure difference characteristic (FK2).

15. A method for operating an extractor hood (2), in particular an extractor hood (2) according to any one of claims 1-14, wherein an electronically commutated fan motor (14) in response to a time signal provided by a timer (27) (t-ι, t ₂ ) with a torque-rotational speed characteristic (DK1) or with a _second torque-rotational speed characteristic (DK1 a, DK1 b, DK3) is controlled by a control device (21).