Pyrolytic oven with a lighting module

Abstract

A pyrolytic oven comprises a housing and a muffle delimiting a cooking chamber inside the housing. A lighting module serves to illuminate the cooking chamber, wherein the lighting module has a cooling structure with an arrangement of cooling extensions formed in particular as pins or ribs, which project into a gap between housing and muffle and have a convection effect in a cooking mode of the oven. A fan device of the oven is configured and controlled to generate an air flow encountering the cooling structure in the gap in a pyrolytic mode of the oven. The cooling structure of the lighting module further has a wall formation, which in pyrolytic mode generates a wind shadow relative to the air flow for a number of cooling extensions of the cooling structure arranged distributed in a transverse plane to the flow direction of the air flow.

Claims

1. A pyrolytic oven adapted to be selectively operated in a cooking mode and a pyrolytic mode, the oven comprising: a housing; a muffle delimiting a cooking chamber inside the housing; a lighting module for illuminating the cooking chamber, wherein the lighting module has a cooling structure including a wall formation and a plurality of cooling extensions, the plurality of cooling extensions projecting into a gap between the housing and the muffle and transverse to an air flow direction within the gap and, when the oven is operated in the cooking mode, having a convection effect; and a fan device, which is configured and controlled to generate, when the oven is operated in the pyrolytic mode, an air flow encountering the cooling structure in the gap, wherein the wall formation of the cooling structure generates a wind shadow relative to the air flow when the oven is operated in the pyrolytic mode, wherein one or more of the plurality of cooling extensions are arranged to extend into the wind shadow generated by the wall formation.

2. The pyrolytic oven according to claim 1, wherein, when looking in the flow direction of the air flow in the pyrolytic mode, the wall formation has a flow cross section that is larger by a multiple than each cooling extension of the cooling structure.

3. The pyrolytic oven according to claim 1, wherein the wall formation comprises a wall section, which in the pyrolytic mode, generates a wind shadow for at least a predominant number of the cooling extensions.

4. The pyrolytic oven according to claim 1, wherein the wall formation is formed by a single, continuously connected wall section.

5. A pyrolytic oven comprising: a housing; a muffle delimiting a cooking chamber inside the housing; a lighting module for illuminating the cooking chamber, wherein the lighting module has a cooling structure with an arrangement of cooling extensions, which project into a gap between the housing and the muffle and have a convection effect in a cooking mode of the oven; and a fan device, which is configured and controlled to generate an air flow encountering the cooling structure in the aa in a pyrolytic mode of the oven, wherein the cooling structure of the lighting module includes a wall formation, which in the pyrolytic mode generates a wind shadow relative to the air flow for a number of cooling extensions of the cooling structure arranged distributed in a transverse plane to the flow direction of the air flow, wherein the wall formation has a wall section formed in the manner of a curly bracket, the central web of which faces the air flow in the pyrolytic mode of the oven.

6. A pyrolytic oven comprising: a housing; a muffle delimiting a cooking chamber inside the housing; a lighting module for illuminating the cooking chamber, wherein the lighting module has a cooling structure with an arrangement of cooling extensions, which project into a gap between the housing and the muffle and have a convection effect in a cooking mode of the oven; and a fan device, which is configured and controlled to generate an air flow encountering the cooling structure in the gap in a pyrolytic mode of the oven, wherein the cooling structure of the lighting module includes a wall formation, which in the pyrolytic mode generates a wind shadow relative to the air flow for a number of cooling extensions of the cooling structure arranged distributed in a transverse plane to the flow direction of the air flow, wherein the cooling extensions stand in the pyrolytic mode substantially along their entire height in the wind shadow of the wall formation.

7. A pyrolytic oven comprising: a housing; a muffle delimiting a cooking chamber inside the housing; a lighting module for illuminating the cooking chamber, wherein the lighting module has a cooling structure with an arrangement of cooling extensions, which project into a gag between the housing and the muffle and have a convection effect in a cooking mode of the oven; and a fan device, which is configured and controlled to generate an air flow encountering the cooling structure in the gap in a pyrolytic mode of the oven, wherein the cooling structure of the lighting module includes a wall formation, which in the pyrolytic mode generates a wind shadow relative to the air flow for a number of cooling extensions of the cooling structure arranged distributed in a transverse plane to the flow direction of the air flow, wherein the cooling extensions are arranged distributed in a two-dimensional regular lattice and the wall formation has a wall section, which extends in one of the two lattice dimensions continuously connectedly over the entire lattice width measured in this lattice dimension.

8. The pyrolytic oven according to claim 1, wherein the wall formation is manufactured from the same material as the cooling extensions.

9. A pyrolytic oven comprising: a housing; a muffle delimiting a cooking chamber inside the housing; a lighting module for illuminating the cooking chamber, wherein the lighting module has a cooling structure with an arrangement of cooling extensions, which project into a gap between the housing and the muffle and have a convection effect in a cooking mode of the oven; and a fan device, which is configured and controlled to generate an air flow encountering the cooling structure in the gap in a pyrolytic mode of the oven, wherein the cooling structure of the lighting module includes a wall formation, which in the pyrolytic mode generates a wind shadow relative to the air flow for a number of cooling extensions of the cooling structure arranged distributed in a transverse plane to the flow direction of the air flow, wherein the wall formation stands up above a base plate of the cooling structure, above which the cooling extensions also stand up with an orientation perpendicular to the plate plane.

10. The pyrolytic oven according to claim 9, wherein the wall formation is manufactured in one piece continuously with the cooling extensions and the base plate.

11. The pyrolytic oven according to claim 9, wherein the base plate has an approximately circular plate outline.

12. The pyrolytic oven according to claim 9, wherein the base plate is attached to a rear side of a circuit board, on the front side of which at least one light source of the lighting module is arranged.

13. The pyrolytic oven according to claim 1, wherein the fan device is configured and controlled to generate the air flow also in cooking mode of the oven, but with a changed flow direction compared with the pyrolytic mode, due to which the cooling extensions lie outside the wind shadow of the wall formation.

14. A pyrolytic oven comprising: a housing; a muffle delimiting a cooking chamber inside the housing; a lighting module for illuminating the cooking chamber, wherein the lighting module has a cooling structure with an arrangement of cooling extensions, which project into a gap between the housing and the muffle and have a convection effect in a cooking mode of the oven; and a fan device, which is configured and controlled to generate an air flow encountering the cooling structure in the gap in a pyrolytic mode of the oven, wherein the cooling structure of the lighting module includes a wall formation, which in the pyrolytic mode generates a wind shadow relative to the air flow for a number of cooling extensions of the cooling structure arranged distributed in a transverse plane to the flow direction of the air flow, wherein the cooling structure is arranged movably between various positions, of which a first position brings about a position of the number of cooling extensions in the wind shadow of the wall formation and a second position brings about a position of the number of cooling extensions outside the wind shadow of the wall formation with an unchanged flow direction of the air flow.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a side view of a pyrolytic oven in a vertical section.

(2) FIG. 2 shows an enlarged extract of the pyrolytic oven shown in FIG. 1 with a lighting module inserted therein.

(3) FIG. 3 shows a view in perspective of a cooling structure of the lighting module shown in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

(4) A pyrolytic oven 10 shown in FIG. 1 comprises a housing 12 and a muffle 16 delimiting a cooking chamber 14 inside the housing 12. The muffle 16 is accessible via an oven door 18 mounted on the housing 12, which door is mounted pivotably on the housing 12 about a horizontal shaft 19 between a position closing the cooking chamber 14 and a position releasing the latter. The oven door 18 is provided with a viewing window, through which a user can look into the cooking chamber 14. The oven 10 further comprises a control unit, which is not shown here and which executes control functions of the oven 10 and is preferably accommodated above the muffle 16 and inside the housing 12. The oven 10 is provided with a gap 20 between the housing 12 and the muffle 16.

(5) A lighting module 22 of the oven 10 is used to illuminate the cooking chamber 14 and is inserted into a wall section of the muffle 16. The lighting module 22 comprises at least one circuit board 24, on the front side of which facing the cooking chamber 14 at least one light-emitting diode 25 (FIG. 2) is provided for emitting light, and a lens 26 (including a window glass, at which the light emerges into the cooking chamber 14) for guiding the beam and for thermal insulation of the light-emitting diode 25 from the cooking chamber 14. In the present case the lighting module 22 is inserted in a side wall of the muffle 16 lying opposite the oven door 18. Alternatively, the lighting module 22 can be inserted into a side wall adjoining the oven door 18 or ceiling wall of the muffle 16. As shown in FIG. 2, the wall section of the muffle 16 taking up the lighting module 22 comprises a receiving opening 28, into which the lighting module 22 is inserted. The circuit board 24 with the at least one light-emitting diode 25 is taken up in the receiving opening 28 of the wall section. The oven 10 is configured and controlled so that the light-emitting diode of the lighting module 22 is switched on in a cooking mode of the oven 10, so that light emitted by this illuminates the cooking chamber, and is switched off in pyrolytic mode of the oven 10.

(6) The lighting module 22 has a cooling structure 30 with an arrangement of cooling extensions 32, which project into the gap 20 between housing 12 and muffle 16 and have a convection effect in a cooking mode of the oven 10. The cooling extensions 32 are formed in the present case in the shape of pins. Alternatively, the cooling extensions 32 can be formed in the shape of ribs. The cooling structure 30 is used to transfer heat between the lighting module 22, in particular the light-emitting diode, and an air flow 34 flowing through the gap 20.

(7) A fan device 36 of the oven 10 is used to generate the air flow 34 in the gap 20 in operation of the oven 10. In particular, the fan device 36 is configured and controlled to generate an air flow 34 encountering the cooling structure 30 in the gap 20 in cooking mode and in pyrolytic mode of the oven 10. To do this the fan device 36 supplies the gap 20 with outside air from an environment of the oven 10 as cooling air via a cooling air inlet, which is not shown here, and conducts this in the form of the air flow 34 through the gap 20. After flowing through the gap 20, the air flow 34 generated thus is conducted via a cooling air outlet, not shown here, into the environment of the oven 10.

(8) In cooking mode of the oven 10, the light-emitting diode 25 is switched on, so that a heat input induced by a power loss of the light-emitting diode takes place into the lighting module 22. The temperature inside the lighting module 22 increases in this way. Because the air flow 34, which has a lower temperature in the cooking mode than the lighting module 22, flows towards the cooling structure 30, a heat transfer takes place from the cooling structure 30 in the direction of the air flow 34 and thus cooling of the lighting module 22 occurs. In other words, in cooking mode a first heat flow Q.sub.1 is generated by the lighting module 22 in the direction of the air flow 34.

(9) In the pyrolytic mode of the oven 10, temperatures of between 480 C. and 500 C. are reached in the cooking chamber 14. This leads to the air flow 34 heating up much more strongly in comparison with the cooking mode on flowing through the gap 20 and reaching temperatures of over 140 C. in the region of the cooling structure 30 of the lighting module 22, which is above a maximum temperature permissible for the light-emitting diode. In pyrolytic mode a second heat flow Q.sub.2 is thus generated by the air flow 34 in the direction of the lighting module 22. To counteract overheating of the lighting module 22 in pyrolytic mode, the cooling structure 30 further comprises a wall section 38, which is shown in FIG. 3 and in pyrolytic mode generates a wind shadow relative to the air flow 34 for a number of cooling extensions 32 of the cooling structure 30, which are arranged distributed in a transverse plane to the flow direction X of the air flow 34. In the present case the transverse plane is a plane spanned by a longitudinal direction Z and a transverse direction Y normal thereto of the cooling structure 30. The flow direction X is respectively normal here to the longitudinal direction Z and the transverse direction Y. When looking in the flow direction X of the air flow 34 in pyrolytic mode, the wall section 38 has a flow cross section that is larger by a multiple, for example at least 5-fold or at least 10-fold, than each cooling extension 32 of the cooling structure 30.

(10) The wall section 38 produces a wind shadow for the total number of cooling extensions 32 in pyrolytic mode. It is formed approximately in the manner of a curly bracket (i.e. {). A central web 42 of the wall section 38 faces the air flow 34 in pyrolytic mode of the oven 10. As shown in FIG. 3, the wall section 38 comprises two adjoining first sections 44 curved in the direction of the cooling extensions 32, which sections form the central web 42. At ends of the first sections 44 facing away from the central web 42, these respectively adjoin second sections 46 curved in the opposite direction compared with the first section 44. This configuration of the wall section 38 has the effect that the air flow 34 encountering the wall section 38 in the flow direction X is conducted in a very largely laminar manner around the cooling extensions 32.

(11) The cooling extensions 32 are formed so that in pyrolytic mode the cooling extensions 32 stand substantially along their entire height, i.e. along their extension in the longitudinal direction Z, and/or width, i.e. along their extension in transverse direction Y, in the wind shadow of the wall section 38.

(12) The cooling extensions 32 are arranged distributed in a two-dimensional regular lattice. The two-dimensional lattice extends in the present case along the flow direction X and the transverse direction Y. The wall section 38 extends here in the lattice dimension along the transverse direction Y continuously connected over the entire lattice width b1 measured in this lattice dimension and beyond. In other words, the wall section 38 has a width b2 that is greater along the transverse direction Y compared with the lattice width b1. It is manufactured from the same material as the cooling extensions 32, e.g. from aluminium or aluminium oxide. Alternatively, the wall section 38 can be manufactured from another material compared with the cooling extensions 32.

(13) The wall section 38 stands up above a base plate 48 of the cooling structure 30, above which the cooling extensions 32 also stand up with a substantially perpendicular orientation to the plate plane of the base plate 48. The wall section 38 is produced in one piece continuously with the cooling extensions 32 and the base plate 48. The base plate 48 has an approximately circular plate outline and is attached to a rear side of the circuit board 24, on the front side of which the at least one light-emitting diode 25 of the lighting module 22 is arranged.

(14) On account of the higher temperature of the air flow 34 in pyrolytic mode as compared to the cooking mode, a difference between the temperature prevailing in the light-emitting diode 25 and the temperature of the air flow 34 is smaller in pyrolytic mode than in cooking mode. This has the effect that the second heat flow Q.sub.2 transferred in pyrolytic mode is smaller in amount than the first heat flow Q.sub.1 transmitted in cooking mode. The present arrangement accordingly facilitates adequate cooling of the lighting module 22 in cooking mode and at the same time adequate protection against an excessive heat input into the lighting module 22 in pyrolytic mode.

(15) To amplify this technical effect, the oven 10 can further be configured and controllable so that a thermal resistance of the cooling structure 30 is set to be greater in the heat transfer between lighting module 22 and the air flow 34 in cooking mode than in pyrolytic mode of the oven 10. To this end the fan device 36 can be configured and controllable to generate an air flow 34 in the cooking mode of the oven 10 with a changed flow direction compared with the pyrolytic mode, due to which the cooling extensions 32 lie outside the wind shadow of the wall section 38. The air flow 34 generated in cooking mode flows counter to the flow direction X of the air flow 34 in pyrolytic mode, as shown in FIG. 3. In this way a higher heat transfer coefficient and thus a lower thermal resistance can be set in cooking mode as compared with pyrolytic mode. Alternatively or in addition, the cooling structure 30 can be arranged movably between various positions, of which a first position brings about a position of the number of cooling extensions 32 in the wind shadow of the wall section 38 and a second position brings about a position of the number of cooling extensions 32 outside the wind shadow of the wall section 38 with an unchanged flow direction of the air flow 34. For example, the cooling structure 30 can be rotatable by means of an actuation unit about the longitudinal direction Z, so that the cooling inserts 32 can be positioned in the wind shadow generated by the wall section 38 or outside the same.

(16) Although the preferred embodiments of the present invention have been described herein, the above description is merely illustrative. Further modification of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention as defined by the appended claims.