DOMESTIC COOKING APPLIANCE HAVING A SENSOR THAT IS LONGITUDINALLY MOVABLE BY MOTOR POWER

Abstract

A household cooking appliance includes a cooking compartment wall delimiting a cooking compartment, a guide sleeve provided on the cooking compartment wall and having a cooking compartment-side end opening which opens into the cooking compartment, a sensor housed in the guide sleeve for longitudinal movement by motor power, and a closure element designed for movement by motor power together with the sensor between a closed position in which the closure element closes the end opening as the sensor is located in an end-opening-distal rest position, and an open position in which the closure element clears the end opening as the sensor is located in an end-opening-proximal measuring position.

Claims

1-10. (canceled)

11. A household cooking appliance, comprising: a cooking compartment wall delimiting a cooking compartment; a guide sleeve provided on the cooking compartment wall and having a cooking compartment-side end opening which opens into the cooking compartment; a sensor housed in the guide sleeve for longitudinal movement by motor power; and a closure element designed for movement by motor power together with the sensor between a closed position in which the closure element closes the cooking compartment-side end opening when the sensor is located in an end-opening-distal rest position, and an open position in which the closure element clears the cooking compartment-side end opening for the sensor when the sensor is located in an end-opening-proximal measuring position.

12. The household cooking appliance of claim 11, further comprising a sensor sleeve housed in the guide sleeve for longitudinal movement by motor power, and a rod system designed to connect the sensor sleeve to the closure element, said sensor being attached to a cooking compartment-side end face of the sensor sleeve.

13. The household cooking appliance of claim 11, wherein the closure element is a pivotable closure flap.

14. The household cooking appliance of claim 11, wherein the closure element is made of a poor thermally conductive material.

15. The household cooking appliance of claim 11, further comprising a microwave function, said closure element designed to be microwave-tight in an overlapping region with the cooking compartment-side end opening of the guide sleeve.

16. The household cooking appliance of claim 11, further comprising a microwave function, said guide sleeve being designed to be electrically conductive on a lateral surface thereof and electrically connected to the cooking compartment wall.

17. The household cooking appliance of claim 11, wherein in the rest position the closure element is positioned in an airtight manner on the cooking compartment-side end opening of the guide sleeve.

18. The household cooking appliance of claim 11, wherein the sensor is an IR sensor, said closure element having an inner surface with an emissivity of approximately 1 in an IR spectral range of the sensor at least in an overlapping region of the closure element.

19. A method for operating a household cooking appliance which comprises a cooking compartment delimited by a cooking compartment wall, a guide sleeve with a cooking compartment-side end opening, a sensor housed in the guide sleeve, and a closure element, said method comprising: moving the sensor through selective actuation of a drive motor between a rest position in which the sensor is located distal to the cooking compartment-side end opening and the closure element assumes a closed position in which the cooking compartment-side end opening is closed, and a measuring position in which the sensor is located proximal to the cooking compartment-side end opening and the closure element assumes an open position in which the cooking compartment-side end opening is cleared.

20. The method of claim 29, wherein the sensor is an IR sensor, and the closure element has an inner surface with an emissivity of approximately 1 in an IR spectral range of the sensor at least in an overlapping region of the closure element, and further comprising: detecting with a temperature probe a cooking compartment temperature of the cooking compartment; and calibrating the sensor by comparing a thermal radiation detected on the inner surface of the closure element and the cooking compartment temperature detected by the temperature probe.

Description

[0052] The above-described properties, features and advantages of this invention and the manner in which they are achieved become clearer and more readily understood in connection with the following schematic description of an exemplary embodiment which is explained in more detail in combination with the drawings.

[0053] FIG. 1 shows, as a sectional drawing in side view, components of a household cooking appliance with the sensor in its measuring position; and

[0054] FIG. 2 shows, as a sectional drawing in side view, the components of the household cooking appliance of FIG. 1 with the sensor in its rest position.

[0055] FIG. 1 shows, as a sectional drawing in side view, components of a household cooking appliance 1 in the form of a combined oven/microwave oven. In particular, a muffle 2 which also serves as cooking compartment wall 3 of a cooking compartment 4 is illustrated. A dome 5 for receiving a rotating antenna (not shown) is illustrated in a ceiling 3a of the cooking compartment wall 3, in particular centrally, microwaves being able to be supplied thereby into the cooking compartment 4. The dome 5 is separated from the actual cooking compartment 4 by a cover 6 which is permeable to microwaves. In the cooking compartment 4 there is also at least one heating element 7 for heating the cooking compartment 4 and/or for irradiating food to be cooked with heat radiation, in this case a tubular top heat and/or grill resistance heating element which is arranged on the ceiling side.

[0056] A guide sleeve 8 in the form of a rectilinear, circular cylindrical tube is arranged on the ceiling 3a. This guide sleeve has an edge 10 which is bent over in the manner of a flange on its cooking compartment-side end opening 9 which opens into the cooking compartment 4. The guide sleeve 8 in this case is a separately produced component which has been passed from the cooking compartment 4 through a through-hole or hole in the ceiling 3a such that the edge 10 bears on the inner face against the ceiling 3a and has been fastened thereto in an airtight manner, for example by laser welding. In the present case, the edge 10 is configured obliquely to a longitudinal axis of the guide sleeve 8 so that the mounted guide sleeve 8 is located obliquely. This improves the view into the cooking compartment 4 when the guide sleeve 8 is arranged eccentrically.

[0057] If the guide sleeve 8 consists of metal, it is electrically connected to the cooking compartment wall 8 which is also metallic. The diameter of the guide sleeve 8 in this case is ca. 16 mm and, as a result, in a metallic or metal-coated embodiment is impermeable to microwaves at frequency ranges typical for household microwave appliances of around 915 MHz or 2.45 GHz. The guide sleeve 8 can have small holes or apertures which, in particular, do not influence a resistance to microwaves. As a result, an improved cooling of the at least one sensor 14 can be achieved, since the cooling airflow of a conventionally installed appliance cooling fan (not shown) can be used in this manner in order to generate an airflow through the guide sleeve 8.

[0058] A sensor sleeve 11 is housed in the guide sleeve 8 so as to be longitudinally movable by motor power. This is achieved by an outer face of the sensor sleeve 11 being configured with a row of teeth 12 extending in the longitudinal direction and the guide sleeve 8 having in its lateral surface or side wall an aperture 20 through which the row of teeth 12 is exposed. The household cooking appliance 1 also has an electric motor 21, a gear wheel 22 being positioned on the drive shaft thereof and the ring gear thereof in turn engaging through the aperture 20 in the row of teeth 12. By actuating the electric motor 21 and by a corresponding rotation of the gear wheel 22, the sensor sleeve 11, as indicated by the double arrow P1, can move between two end positions, and namely between the measuring position shown and a rest position explained in more detail below and shown in FIG. 2.

[0059] A sensor, in this case an IR sensor 14, which in the variant shown terminates flush with the cooking compartment-side end face 13 is incorporated on the cooking compartment-side end face 13 of the sensor sleeve 11. Thus the IR sensor 14 is also housed in the guide sleeve 8 so as to be longitudinally movable by motor power. Outside the rest position, the IR sensor can be moved or is moved out of the guide sleeve 8as shown for the measuring position. The IR sensor can have, for example, a diameter of ca. 10 mm which thus also corresponds to the internal diameter of the tubular sensor sleeve 11.

[0060] A rod 15 is rotatably connected to the sensor sleeve 11, the rod protruding relative to the sensor sleeve 11 on the cooking compartment side. On the other side, the rod 15 is connected to a closure flap 17 which is pivotably attached to the edge 10 via a hinge 16, resulting in a possibility of movement of the closure flap 17 as indicated by the double arrow P2. More specifically, the other end region of the rod 15 is rotatably connected to a projection 19 protruding vertically in an overlapping region 18 of the closure flap 17.

[0061] In the measuring position of the IR sensor 14 shown, the closure flap 17 is pivoted by the rod 15 sufficiently far away from the end face 13 of the sensor sleeve 11 that the cooking compartment-side end opening is cleared for the IR sensor and the closure flap 17 is no longer located in the field of view F of the IR sensor 14. The IR sensor 14 can thus record a thermal image of the cooking compartment 4 uninterrupted by the closure flap 17.

[0062] If the sensor sleeve 11 is retracted out of the measuring position into the guide sleeve 8, the IR sensor 14 is also retracted into the guide sleeve 8 until reaching a rest position which is further away from the cooking compartment 4. The IR sensor 14 and the closure flap 17 thus can be moved together by the electric motor by motor power.

[0063] Generally the sensor sleeve 11 can be moved between the operating position and the rest position. In one development, the sensor sleeve 11 can also be moved in a targeted manner to intermediate positions.

[0064] If the sensor sleeve 11 is retracted into the guide sleeve 8, it pulls the rod 15 therewith into the guide sleeve 8, whereby the closure flap 17 is pivoted about the hinge 16 in the direction of the cooking compartment-side end opening 9. This closing movement can be continued until the IR sensor 14 is located in its rest position, in which case the closure flap 17 is in its closed position in which it covers the cooking compartment-side end opening 9. The covering region 18 thus faces into the guide sleeve 8. The projection 19 is also housed in the guide sleeve 8.

[0065] The closure flap 17 or the edge 10 can be configured so as to be sealed, for example by providing a sealing ring (not shown) or a sealed coating. Thus in the rest position an entry of air into the guide sleeve 8 can be particularly reliably avoided.

[0066] The closure flap 17 can be configured, in particular, in a disk-shaped manner and, for example, can be configured (for example covered or coated) to be metallic on its side (outer face) facing into the cooking compartment 4 in the rest position, and on its inner face which faces into the guide sleeve 8 in the rest position and which corresponds to the covering region 18, it can consist of a poor thermally conductive material, for example of plastic, ceramic, micanite, or the like. An entry of microwaves into the guide sleeve 8 can also be particularly effectively prevented by the metallic layer.

[0067] In particular, the covering region 18 can have a surface with an emissivity of approximately 1. In this case, the covering region 18, which is located in the rest position of the IR sensor 14 in the field of view thereof, can be used to calibrate the IR sensor 14 in its rest position.

[0068] In a cooking sequence, the household cooking appliance 1 can be operated, for example, as follows;

[0069] In a variant, thermal images from the cooking compartment 4, and thus also of food to be cooked which is located in the cooking compartment 4, can be recorded practically continuously or at short time intervals. To this end, the electric motor is actuated at the start of the cooking sequence, such that the sensor sleeve 11 is moved forward out of the retracted rest position in the direction of the cooking compartment 4, and via the rod 15 which pushes open the closure flap 17, which was previously located in its closed position, so that this closure flap lifts away from the cooking compartment-side end opening 9. The sensor sleeve 11 is moved sufficiently far until the measuring position shown in FIG. 1 is reached. In the measuring position, the thermal images are recorded by the IR sensor 14. The sensor sleeve 11 is retracted in the reverse direction into the guide sleeve 8, in particular if (a) the IR sensor 14 is no longer required, for example because the cooking sequence is terminated and/or (b) the IR sensor 14 could be damaged, for example because the cooking compartment temperature has reached or exceeded a predetermined threshold value. In the rest position, the IR sensor 14 is protected relative to the cooking compartment 4 by the closure flap 17 and namely relative to microwaves, thermal radiation and a cooking compartment atmosphere. Additionally, in the rest position the IR sensor 14 is moved relatively far away from the cooking compartment 4 so that the thermal stress thereof is also reduced thereby.

[0070] In a further variant, thermal images are recorded at longer time intervals. To this end, the IR sensor 14 only needs to be moved out of the rest position into its measuring position for one respective recording, and is moved back again into its rest position after the recording.

[0071] Naturally the present invention is not limited to the exemplary embodiment shown.

[0072] Generally one, etc. can be understood to mean a singular or a plurality thereof, in particular in the sense of at least one or one or more, etc. provided this is not explicitly excluded, for example, by the expression exactly one, etc.

[0073] A numerical specification can also encompass exactly the specified number and a usual tolerance range, provided this is not explicitly excluded.

LIST OF REFERENCE CHARACTERS

[0074] 1 Household cooking appliance [0075] 2 Muffle [0076] 3 Cooking compartment wall [0077] 3a Ceiling [0078] 4 Cooking compartment [0079] 5 Dome [0080] 6 Cover [0081] 7 Heating element [0082] 8 Guide sleeve [0083] 9 Cooking compartment-side end opening [0084] 10 Edge [0085] 11 Sensor sleeve [0086] 12 Toothed rack [0087] 13 End face [0088] 14 IR sensor [0089] 15 Rod [0090] 16 Hinge [0091] 17 Closure flap [0092] 18 Overlapping region [0093] 19 Projection [0094] 20 Aperture in guide sleeve [0095] 21 Electric motor [0096] 22 Gear wheel [0097] P1 Double arrow [0098] P2 Double arrow