The present invention relates to a steam oven device as well as to a water tank for use in a respective device.

Known steam ovens use different approaches as far the water tank position and configuration is concerned. These approaches may be summarised as follows:

1. a) The water tank is positioned side-by-side with the cooking cavity of the steam oven and stands in upright format. Since the width of the steam oven is limited to the standard built-in furniture dimensions the width of the cooking cavity has to be reduced to accommodate the water tank thus reducing the width the associated food-trays. Such a steam oven is disclosed in DE 19741881 A1 and EP 1108384 A1.
2. b) The water tank is positioned behind the control panel for controlling the cooking operation. Access to the water tank is gained through a door arranged in the control panel. This kind of arrangement has the disadvantage that humidity from the water tank may badly affect or destroy the electronic components of the control panel. Further, the manufacturing of the face plate for the control panel is more expensive since an aperture for the door of the water tank is required.
3. c) The water tank is positioned inside the steam oven structure and water is pored into the water tank through an opening arranged in the control panel. As the water tank cannot be removed water remains inside it between subsequent cooking cycles and this presents hygiene problems. Again, an extra opening is required in the face plate of the control panel so that the manufacturing costs are increased in this case too.
4. d) A flat water tank is positioned above the cooking cavity and has generally the same width as the cooking cavity. The flat water tank is completely closed to prevent that water slops out of the water tank into the steam oven when the water tank is moved. A small closable opening is arranged on the top wall of the water tank to fill up water. Hence the water tank is difficult to clean and presents hygienic problems. Such a steam oven is known from EP 1 550 828 A1.

Therefore, it is the object of the present invention to provide a steam oven device and a water tank for use in a respective steam oven device which maximises the size of the cooking cavity, reduces the manufacturing costs and prevents hygiene problems resulting from water remaining in the water tank between subsequent cooking cycles while at the same time improving the outer appearance of the front side of the steam oven device.

This object is achieved by a steam oven device having the features of claim 1 and by a water tank for use in a steam oven device having the features of claim 12. Further features of the present invention are set forth in the subclaims.

The water tank has top wall completely formed as a primary lid so that the interior of the water tank is fully accessible after opening the primary lid. Accordingly, efficient cleaning of the interior of the water tank is possible. The primary lid may have a smaller secondary lid for facilitating refilling of water to the water tank. It is thus not necessary to completely remove the water tank from the receiving slot when water is to be refilled. It is sufficient to extract the water tank from the receiving slot in such a manner that the smaller secondary lid can be opened.

In an embodiment it is proposed to horizontally arrange a water tank receiving slot below the control panel and above the cooking cavity in such a manner that the water tank received in the receiving slot is arranged behind the closed cavity door. This has the advantage that the water tank does not occupy any space on the left or right hand side of the cooking cavity which allows in particular the cavity width to be maximised. In addition, the water tank can be made relatively flat so that the height of the cooking cavity can be maximised too.

According to the invention the water tank is no more situated behind the control panel so that the likelihood of contact between water or humidity and electronic components of the control panel is minimised. The face plate of the control panel does not need to have any kind of additional opening or door for filling in water.

The water tank has a flat geometry defined by its height, width and depth. Preferably the height of the water tank is smaller than 7 % of its width and smaller than 15 % of its depth. The water tank may have a cuboid-like shape or other appropriate flat shapes. Alternatively, the plan view of the water tank may be for example in the shape of a semicircle. Then, the width in the sense of the present invention would be the diameter of the semicircle and the depth in the sense of the present invention would be the radius of the semicircle.

In addition, according to the present invention the height of the water tank is also small if compared with the height of the cooking cavity. It is preferred that the height of the water tank is smaller than 14 % of the height of the cooking cavity.

The water tank is moveable between an extracted position in which it is at least partially extracted from the receiving slot and an operating position in which it is fully received in the receiving slot. For the purpose of refilling water the water tank can be partially extracted from the receiving slot like a sliding drawer. For discharging water from the water tank the latter can be completely removed from the receiving slot.

Preferably the water tank has one or more snap-in connection means for automatically engaging or disengaging a fluid mechanical communication between the water tank and one or more water pumps. When the water tank is moved between the extracted position and the operating position the snap-in connection means are automatically engaged or disengaged with suitable hoses, tubes or pipes connected with the one or more water pumps.

In the front wall of the water tank a recess having the function of a hand grip may be formed. The hand grip may be used to move the water tank between the extracted position and the operating position in the manner of a sliding drawer.

Further, in view of the flat shape of the water tank water inside the tank could swivel during handling and manoeuvring of the water tank. In order to prevent such kind of swivel movement the interior of the water tank may have tranquilising barriers for tranquilising water movements occurring during the handling of the water tank.

Preferably, the steam oven device according to the present invention has two water pumps. The first water pump supplies water from the water tank to the boiler means during a cooking cycle. The second water pump returns the water remaining in the boiler means after the cooking cycle to the water tank thus ensuring that no water remains inside the steam oven water circuit.

Hereinafter, an exemplary embodiment of the present invention is described in connection with the attached drawings, in which:

Fig. 1:

shows a perspective view of an embodiment of the steam oven de- vice according to the present invention;

Fig. 2:

shows a vertical cross sectional view of the steam oven device shown in Fig. 1 with the water tank fully contained in the receiving slot and the cavity door closed;

Fig. 3:

shows a top plan view of the steam oven device shown in Fig. 2 with some upper parts removed in order to make interior components visible;

Fig. 4:

shows a perspective front view of the water tank; and

Fig. 5:

shows a perspective rear view of the water tank shown in Fig. 5.

Fig. 1 shows a built-in steam oven device 7 according to the present invention which is intended to be mounted in a hollow space of a standard built-in furniture. Steam oven device 7 has a cooking cavity 1 for food preparation. Hot water vapour can be directed into the cooking cavity 1 for this purpose. Cooking cavity 1 can be closed by a cavity door 3 shown in Fig. 1 in its open position.

In the upper front region of steam oven device 7 a control panel 2 having control elements 15 for controlling the cooking operation is mounted. Below control panel 2 steam oven device 7 has a water tank receiving slot 8 for receiving a water tank 10. In Fig. 1 water tank 10 is partially extracted from the water tank receiving slot 8.

Fig. 2 shows a vertical cross section along the midplane of steam oven device 7 in Fig. 1. In Fig. 2 cavity door 3 is shown in its closed position. As can be seen, the water tank 10 fully contained in receiving slot 8 lies behind the upper region of cavity door 3. In the shown embodiment the water tank 10 is arranged nearly in the same horizontal plane like cavity door grip 9.

In the top plan view according to Fig. 3 some upper parts of steam oven device 7 have been omitted so that the interior of steam oven device 7 can be seen. As in Fig. 2 cavity door 3 is shown in its closed position and water tank 10 is completely contained in receiving slot 8. Further, a boiler means 6 for vaporising water received from water tank 10 is shown. A first pump 4 serves as inlet pump which pumps water from water tank 10 to boiler means 6 during a cooking cycle. A second pump 5 serves as outlet pump which pumps water remaining in the boiler means after a cooking cycle back to the water tank.

Fig. 4 and 5 are showing exploded views of water tank 10. It is defined by a body - comprising bottom wall 18, side walls 19, 20, rear wall 21 and front wall 16 - and by a top wall 13. Top wall 13 is formed as a primary lid which may be completely removed from the body of water tank 10. Thus, the interior of water tank 10 is fully accessible for cleaning purposes.

As further shown in Fig. 4 and 5, water tank 10 has two snap-in connections 11 in its rear wall 21. When water tank 10 is pushed to its operating position in which it is fully received in receiving slot 8 the snap-in connections 11 automatically provide a fluid mechanical communication with first and second pumps 4, 5. As shown in Fig. 4 front wall 16 has a recess 17 shaped in a way to serve as a hand grip for pulling out water tank 10 from receiving slot 8.

In the shown embodiment primary lid 13 has a smaller secondary lid 14 which is pivotably connected with primary lid 13. Secondary lid 14 can be moved between open and closed positions with respect to an opening 22 provided in primary lid 13 for the purpose of refilling water to water tank 10. Further, Fig. 4 and 5 show four wall-like tranquilising barriers 12 fixed on bottom wall 18. They extend parallel to side walls 19, 20 and are not in contact with front wall 16 and rear wall 21 in order to allow the water to flow through the whole volume of water tank 10. However, the barriers 12 have a tranquilising effect on the flow movement of the water contained in water tank 10.

In the present embodiment water tank 10 has a flat cuboid-like shape as in particular shown in Fig. 1, 4 and 5. In Fig. 4 the width w, the depth d and the height h (thickness of primary lid 13 neglected) are shown. According to the present invention it is preferred that height h is smaller than 7 % of the width w and at the same time smaller than 15 % of the depth d. In addition, it is preferred that the height h of water tank 10 is smaller than 14 % of the height H of cooking cavity 1 as shown in Fig. 1.

1

cooking cavity

2

control panel

3

cavity door

4

first pump

5

second pump

6

boiler means

7

steam oven device

8

water tank receiving slot

9

cavity door grip

10

water tank

11

snap-in connection

12

tranquilising barrier

13

primary lid = top wall

14

secondary lid

15

control element

16

front wall

17

recess

18

bottom wall

19, 20

side walls

21

rear wall

22

opening

w

width of water tank 10

d

depth of water tank 10

h

height of water tank 10

H

height of cooking cavity 1