Method for controlling a fume extraction device

Abstract

The present invention relates to a method for controlling a fume extraction device comprising at least one fan with a motor, characterised in that the motor of the fan is controlled by a regulator in which a predetermined noise level is taken into account. The invention also relates to a fume extraction device.

Description

[0001] Method for controlling an extractor device

[0002] The present invention relates to a method for controlling an extractor device.

[0003] Extractor hoods and downdraft extractors, in particular, use fans, also known as ventilators, to draw air from a hob or worktop into the extractor hood and clean it there. The extractor hood's fan typically has an electrically commutated motor (EC motor) that drives the fan impeller.

[0004] Thanks to electronic commutation, these motors can be easily controlled, or the control can be easily adjusted. In particular, the torque-speed characteristic, and thus also the displacement-pressure difference characteristic, can be precisely selected, and the motor can be controlled accordingly.

[0005] For example, characteristic curves that have already been recorded for condensing motors are used or modeled on them.

[0006] A disadvantage of the current approach is that, for example, when back pressure increases, the controller reacts by increasing the speed without taking into account effects that are important for the user.

[0007] The object of the present invention is therefore to provide a solution by means of which the disadvantages of the prior art can at least be reduced.

[0008] The invention is based on the finding that this problem can be solved by controlling the fan using a control system that is generated as a function of at least one user-relevant effect. According to a first aspect, the present invention therefore relates to a method for controlling an extractor device that comprises at least one fan with a motor. The method is characterized in that the fan motor is controlled using a control system that takes a predetermined noise level into account.

[0009] The fan motor is preferably an EC motor.

[0010] The term "noise level" refers specifically to the noise level emitted by the extractor hood during operation, which is thus perceived by the user. The noise level can also be referred to as the noise level or the total noise level. In particular, the noise level is generally composed of a component generated by the operation of the motor and vibrations (also referred to as source total noise), as well as a component generated by the airflow.

[0011] The noise level is influenced by a number of factors. In particular, the noise level is influenced, for example, by the installation situation of the fan in the extractor hood and the installation situation of the extractor hood in the room in which it is operated. The installation situation is influenced, for example, by the piping, in particular its cross-section and / or length. Particularly with smaller diameter pipes, the back pressure that the fan must overcome is increased. The noise level is also influenced by the operating mode of the extractor hood. In particular, the noise level is generally higher with an extractor hood that is operated in recirculation mode (recirculation hood) than with an extractor hood that is operated in exhaust mode (exhaust hood).Recirculation hoods usually use odor filters through which air must flow, thereby increasing the back pressure that the fan must overcome.

[0012] By taking a specified noise level into account when controlling the motor, the extractor hood can be operated in such a way that the nuisance caused by the operation of the extractor hood can be minimized. According to one embodiment, the control is carried out using a control curve in which a constant noise level is generated at all operating points. This can further reduce user nuisance.

[0013] According to one embodiment, the predetermined noise level represents a value or a range.

[0014] According to one embodiment, the specified noise level is independent of the installation situation of the extractor hood and / or the installation situation of the fan in the extractor hood. For an extractor hood installed via piping that leads to increased backpressure, the fan motor can, for example, be controlled to operate at a lower speed. Furthermore, a recirculating hood, for example, can also be controlled to produce a lower noise level. In this case, the efficiency of the recirculating hood may be lower than if the recirculating hood were operated without considering the noise level.

[0015] According to one embodiment, the control curve is determined from a pressure-displacement volume curve taking into account the sound pressure values ​​of the delivery volumes.

[0016] According to one embodiment, the speed of the motor represents the control variable. By reducing the speed, for example, the noise level can be reduced.

[0017] According to one embodiment, the specified noise level can be adjusted by the user of the extractor. The adjustment can be made directly on the extractor, for example, by selecting a noise level.

[0018] According to one embodiment, the control of the extractor device is selected by the user depending on a predetermined noise level. This allows the user to decide whether the extractor device is operated with or without such a control. This embodiment is advantageous because it allows the user to decide whether a constant noise level should be set or whether the extractor device should be operated with increased efficiency, possibly accompanied by an increased noise level.

[0019] According to a further aspect, the invention relates to an extractor device comprising at least one fan with a motor and a control unit. The extractor device is characterized in that the extractor device is designed to carry out the method according to the invention.

[0020] Advantages and features described with regard to the method also apply, where applicable, to the extractor device and vice versa and may be described only once.

[0021] According to a preferred embodiment, at least one control curve for constant noise operation of the extractor hood is stored in the control unit of the extractor hood. If multiple control curves are stored, each control curve can be a control curve for a different specified noise level.

[0022] According to one embodiment, the extractor device has at least one operating element via which the control can be selected as a function of a predetermined noise level and / or the predetermined noise level.

[0023] The invention is explained again below with reference to the accompanying figures. They show:

[0024] Figure 1: a schematic block diagram of an embodiment of the extractor device according to the invention; and

[0025] Figures 2 to 5: a schematic representation of measurement results of the operation of extractor hoods according to the method according to the invention.

[0026] The method according to the invention can be carried out, for example, with an extractor device 1 shown in Figure 1. In this embodiment, the extractor device 1 represents an extractor hood.

[0027] Extractor extraction device 1 arranged in an environment close to a cooking surface, in particular above a cooking surface 12. The extractor extraction device 1 comprises a control unit 3 and a fan 2. The fan 2 comprises a motor (not shown) for driving a fan impeller of the fan 2 (not shown). The motor is preferably an EC motor. In the embodiment shown, the control unit 3 is shown separate from the fan 2. Alternatively, the control unit 3 can also be integrated into the fan 2 and, for example, into the motor control of the motor of the fan 2. In addition, the extractor extraction device 1 in the embodiment shown comprises a memory unit 4 which is connected to the control unit 3. One or more control curves can be stored in the memory unit 4.Furthermore, the extractor device 1 in the embodiment shown has an operating unit 5 via which, for example, user inputs can be made and transmitted to the control unit 3.

[0028] The fan 2 is arranged in the extractor device 1. On the underside of the extractor device 1, an intake opening 60 is provided, in which, in the embodiment shown, a filter 7 is provided. From the intake opening 60, the air is drawn to the fan 2. An air duct 6 is connected to the top of the fan 2. In the embodiment shown, the upper end of the air duct 6 protrudes beyond the top of the extractor device 1. A pipe (not shown) can be arranged at the air outlet 61 provided in the upper end of the air duct 6.

[0029] The control unit 3 is configured to control the fan motor 2 according to a control curve stored in the memory unit 3.

[0030] Figures 2 to 5 show measurement results of an embodiment of the method according to the invention. The three curves in each of the figures can have been measured with different extractor hoods, with the same extractor hood in different installation situations, or with the same extractor hood with different selected predefined noise levels. The upper curve in all four figures represents the embodiment with a higher noise level than the two lower curves. In Figure 2, the noise pressure level is plotted against the volume flow. The noise pressure level can also be referred to as the noise level and is preferably specified in decibels (dB, in particular dB(A)). The volume flow can also be referred to as the conveyed volume flow and is preferably specified in cubic meters per hour (m 3 / h).

[0031] The upper curve in Figure 1 shows that a higher noise level is achieved than in the two lower curves. The noise level remains constant in each curve, even at different flow rates.

[0032] Figure 3 plots the static pressure against the volume flow. Static pressure can also be referred to as back pressure and is preferably expressed in Pascals (PA).

[0033] Figure 4 plots the speed against the flow rate. The speed represents the motor's rotational speed and is preferably expressed in revolutions per minute (rpm).

[0034] Figure 5 plots efficiency against volume flow. Efficiency can also be referred to as static efficiency and is preferably expressed as a percentage (%).

[0035] In one embodiment of the present invention, a fan control curve can be used so that the fan noise reaches a constant overall level at all operating points, for example, with all possible piping configurations, in exhaust air mode, in recirculation mode, and the like. The data can be obtained from noise characteristic tests, and the corresponding control curves can be derived from them. The control curve can also be referred to as an operating curve or operating line.

[0036] If multiple control curves are generated for different noise levels, they are preferably selected so that an audible difference always exists. The present invention has a number of advantages. For example, noise-constant control curves, in particular noise-constant fan operating curves, can enable the user to achieve an operating behavior that is clearly defined for one of the output variables, in particular a source total noise of the fan. This is possible without the user having to perform a secondary evaluation of operating data.

[0037] In addition, identical noise levels can be achieved with recirculation and exhaust air modes without any additional effort.

[0038] Since the motor can be controlled specifically, it is possible to switch through different curves in a kitchen studio, for example, to adapt the noise to the exhibition space.

[0039] List of reference symbols

[0040] 1 extractor hood

[0041] 2 fans

[0042] 3 Control unit

[0043] 4 storage unit

[0044] 5 Control unit

[0045] 6 Air duct

[0046] 7 filters

[0047] 12 hob

[0048] 60 intake opening

[0049] 61 Air outlet

Claims

Patent claims 1. Method for controlling a cooker hood comprising at least one fan with a motor, characterized in that the control of the fan motor is carried out by a control system in which a predetermined noise level is taken into account.

2. Method according to claim 1, wherein the control is carried out using a control curve in which a constant noise level is generated at all operating points.

3. Method according to claim 1 or 2, wherein the predetermined noise level represents a value or a range.

4. Method according to one of claims 1 to 3, wherein the predetermined noise level is independent of the installation situation of the extractor hood and / or the installation situation of the fan in the extractor hood.

5. Method according to one of claims 2 to 4, wherein the control curve is determined from a pressure-volume curve taking into account sound pressure values ​​of the volumes being conveyed.

6. Method according to any one of claims 1 to 5, wherein the speed of the motor is the control variable.

7. Method according to one of claims 1 to 6, wherein a noise level currently emitted by the extractor fan is determined and a control curve is selected based on the determined noise level.

8. Method according to any one of claims 1 to 7, wherein the control of the extractor fan can be selected by the user depending on a predetermined noise level. Method according to any one of claims 1 to 8, wherein the predetermined noise level is set by the user. Extractor fan with at least one fan (2) with a motor and a control unit (3), characterized in that the A range hood (1) designed to perform the method according to any one of claims 1 to 9. A range hood according to claim 10, wherein at least one control curve for constant noise operation is stored in the control unit (3). A range hood according to one of claims 10 or 11, wherein the range hood (1) has at least one operating unit (5) by means of which the control can be selected depending on a predetermined noise level and / or the predetermined noise level.

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