DE3120569A1 - Kitchen vapour extractor hood - Google Patents

Description

- 3 - Pat / Pr / ro

Size Bauknecht GmbH P.O. Box 983 Heidenklinge 22

Stuttgart 1

Kitchen extractor hood

The invention relates to a kitchen extractor hood for Exhaust or recirculation mode, which essentially consists of an air box arranged in a hood housing in the drive and impeller »are housed, replaceable filter elements and a compartment for electrical parts.

Devices that are created when cooking over the stove Extracting vapors are known and generally meet the requirements for air performance, i.e. after a Delivery volume of approx. 100 to 400 m / h with counter pressures of 0 to 30 mm water column. The extractor hoods with single-motor, high-speed fans, however, the noise level is very high. With single-motor, slower rotating fans the motor characteristic is badly used. The twin-motor blower requires a lot of effort. Furthermore, with all conventional devices, the vapor is extracted in the middle of the hood, which means that larger quantities of vapor are extracted can pull past the sides of the hood because they

often do not hit the suction area centrally.

The present invention is therefore based on the object of developing an extractor hood which has the above-mentioned disadvantages of known devices does not have. It should have the dimensions of the usual kitchen standards and if possible high speed of the fan drive of approx. 2400 to 2700 revolutions / min, have a minimal noise level.

It has been shown that this task can be achieved with a kitchen hood the type mentioned can be solved, in which the suction surface of the air box facing away from the kitchen vapors and the suction openings are arranged on the lower surface of the hood housing and along the suction openings Within the intake ducts or chambers, several silencer tubes are provided, which via deflection sections are connected to the air box. The suction openings are preferably at the edge regions of the lower surface of the hood housing and in particular at two opposite edge areas appropriate. Some preferred embodiments of the The device according to the invention are described in the subclaims 2 to 10.

The advantages achieved by the invention are essentially to be seen in the fact that the overall efficiency of the device is increased while the noise level is reduced by more than 10 dB in the case of a single-motor version. As a result of that the suction surface of the air box faces away from the kitchen fumes, a bell effect is enabled during suction and thus avoiding evasion of the haze.

The invention is explained in more detail with reference to the accompanying drawings. It show in schematic simplification

Figure 1 shows a device according to the invention in a pull-out version in cross section parallel to the hood

front surface;

FIG. 2 in section A-A the hood shown in FIG. 1;

FIG. 3 shows the section shown in FIG. 2 with the hood pulled out and

FIG. 4 shows the hood shown in FIG. 1 in section B-B.

In the following, the invention is illustrated using the example of a pull-out device for both recirculation and exhaust air operation suitable cooker hood. Switching to the appropriate operating mode can be done manually in the usual way.

The device according to the invention is like known range hoods operated with a drive 1 and a fan wheel 2, which are located within an air box 3 which is housed in the hood housing 4. The essential one The difference to the prior art is that the air box 3 with the suction surface 5 points upwards, so that this is turned away from the kitchen vapors.

The air box 3 is preferably designed in a spiral shape on the inside and is arranged in the center of the housing 4. Another opening 6 leads to the exhaust ducts 7. The intake opening of the air box is coordinated with the fan wheel 2 so that

10

that a lateral air flow (short circuit) does not occur can and the sucked in air only enters the fan wheel 2.

The fan wheel 2 preferably has 12 to 20 backward curved ones Shovels 8 open. The motor 1 is arranged in the middle, for example. Preferably, a motor with a Speed from approx. 2400 to 2700 revolutions / min, for normal operation used.

The suction opening 5 of the air box is from above with air to flow channels 9 connected.

In this version, the air is drawn from the two opposite Sucked in edges 10 of the hood lower surface.

At these points there are several silencer tubes in appropriately designed chambers 12, which are covered with an absorption material, e.g. foams with a closed surface are filled. The chambers 12 are to the suction surfaces 10 closed at the bottom, e.g. by plastic plates 13. The silencer tubes 11 protrude through an opening in these plates a little out and are called Helmholtz resonators or designed as a reflection damper. The chambers and the silencer tubes 11 are via a deflection section or an air inflow channel 9 with the opening 5 of the air box tied together.

A circulating air duct 14 is provided above the deflection path 9, which is in communication with the opening 6 of the air box. In recirculation mode, the cleaned and filtered Air is diverted through the opening 15.

From Figure 2, the A-A section of the device shown in Figure 1, it can be seen that laterally over the suction surfaces 10 three silencer tubes 11 in three chambers 12 and

• ·

10

are accommodated. In this embodiment, the diameter of each silencer tube is approximately 60, the height approximately 80 mm. The silencer tubes can also be arranged on the front edge of the hood, for example. With a total of six Silencer pipes, i.e. three on each side, a sufficient noise reduction is achieved. Also is through an extension the silencer pipes a more targeted suction possible, whereby the required air delivery volume and thus also the Transmission heat requirement is reduced. For this purpose, the silencer tubes can, for example, be constructed in a telescopic manner. One Another option for targeted suction is provided if the silencer pipes, for example, can be individually closed which increases the suction speed in the silencer tubes that remain open directly above the hob will.

The air extraction ducts 16 are located behind the air box 3, which cannot be drawn in here, preferably from an elastic and compressible material, which leads to the exhaust ducts 7 and to the circulating air duct 14, which is located between the two-sided chambers 12 located on the upper part of the hood housing 4, lead.

The front surface of the hood is provided with a flap 17 which can be opened when the hood is in operation, so that it may be further suction openings can be exposed, e.g. if air should also be sucked in at the front of the hood.

Preferably the entire undersurface of the hood is covered with a grease filter 18 provided. The filter area should be as large as possible in order to minimize the flow resistance of the filter as possible to keep. Like the carbon filter 19, the grease filter 18 is made in two parts so that

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pulling the hood results in a continuous filter surface. Preferably there is a small distance between the lower surface of the air box 3 and the grease filter, so that an optimal one Air flow is guaranteed. The filter inserts 18 and 19 are attached in the usual way to be exchangeable.

It is also clear from FIG. 2 that a compartment 20 for electrical parts is also provided on the rear part of the hood.

Figure 3 shows the same A-A section in the pulled-out state of the hood. The flue duct 16 which expands when it is pulled out leads to the two exhaust ducts 7 and also to the circulating air box 14, which is not shown here and is behind the chambers 12 is located. The filter inserts 18 and 19 form a continuous surface, with the carbon filter 19 only the suction surface 10 needs to cover.

The BB cut is shown in Figure 4. The air duct 14 has a bypass opening 21 which is exposed when the flap 17 is opened. According to the principle of a water jet pump, air can additionally be sucked in through this opening when the opening 15 is closed during exhaust air operation. Such a measure is also conceivable for circulating air operation, but in this case the bypass opening would have to be attached to another suitable location. A grease filter is preferably also provided in front of the bypass opening 21. The bypass section significantly increases the efficiency of the blower with small counter pressures, for example by 10 %.

If the back pressure is too high, e.g. more than 10 mm water column, the bypass opening 21 is opened by a valve or back-up plate 22 closed so that the sucked in air cannot be pushed back into the room.

Instead of the bypass opening 21 and valve plate 22, one of the silencer tubes 11, preferably the elastic one, can also be used Flue ducts 16 adjacent muffler pipe are provided with a bypass opening.

The circulating air duct 14 is provided on the lower surface or on suitable surfaces with absorbent material 23 so that it serves as a muffler run.

i mm **

. · '. .: 10

-40-

Reference number

1 drive

2 fan wheel

3 air box

4 hood housings

5 suction area

6 openings on the air box to exhaust air ducts and recirculation box q

7 exhaust ducts

.8 Impeller blades

9 deflectors

10 suction surfaces

11 silencer pipes

12 Chamber for silencer pipes

13 Chamber end plate

14 air circulation box

15 air circulation opening

16 air extraction channels

17 front door

18 grease filters

19 carbon filters

20 Housings for electrical parts

21 bypass opening

22 Valve plate for bypass opening

23 absorbent material

Claims (10)

G. Bauknech-t GmbH 10 590 S ° fi ^fa P ?, ⁹⁸³ _oo I8 _e May 1981 Pagan blade 22 Stuttgart 1 pat / pr / ro Kitchen extractor hood Claims M. ) Kitchen extractor hood for exhaust air or recirculation mode, consisting essentially of an air box arranged in a hood housing in which the drive and fan wheel are housed, replaceable filter inserts and a compartment for electrical parts, characterized in that the suction surface (5) of the air box (3) facing away from the kitchen fumes and the suction openings (.10) are arranged on the lower surface of the hood housing (4), and that a plurality of silencer pipes (11) are provided along the suction openings (10) within suction channels or chambers (12) which are connected to the air box (3) via deflection sections (9). 2. Kitchen Exhaust hood according to claim 1, characterized n · * gekennzeich et that suction openings (10) are attached to edge regions of the lower surface of the cap body (4), preferably on two opposite edge regions. 3. Kitchen extractor hood according to claim 1 or 2, characterized in that a common deflection section (12) is provided for a plurality of silencer pipes (11) in each case in an edge region. 4. Kitchen extractor hood according to one of claims 1 to 3, characterized in that at least three silencer tubes (11) are provided at each edge region along the suction opening (10). 5. Kitchen extractor hood according to claim 4, characterized in that the silencer pipes (11) have a diameter of 60 mm and a height of 80 now. ' _: 6. Kitchen extractor hood according to claim 5, characterized in that the silencer tubes (11) can be closed and telescoped, preferably to a length of 20 to 50 cm, can be pulled out. 7. Kitchen extractor hood according to one of claims 1 to 6, characterized in that above the air box (3) a circulating air or muffler channel (14) provided with air circulation openings (15) is arranged. 8. kitchen extractor hood according to claim 7, characterized in that the silencer duct (14) can be pulled out to the front. 9. Kitchen extractor hood according to one of claims 1 to 8, characterized in that the fan is provided in parallel bypass sections through which ambient air is sucked in during exhaust air operation. 10. kitchen extractor hood according to claim 9, characterized in that the silencer channel (14) serves as a bypass section and the bypass openings (21) with backflow flaps (22) • are provided.