WO2012162480A1

WO2012162480A1 - An oven with a cooled lighting device

Info

Publication number: WO2012162480A1
Application number: PCT/US2012/039307
Authority: WO
Inventors: Andrea GALLUCCI; Massimo Peruzzo; Daniele Turetta
Original assignee: Illinois Tool Works Inc.
Priority date: 2011-05-25
Filing date: 2012-05-24
Publication date: 2012-11-29
Also published as: ITTO20110456A1; EP2715238A1

Abstract

An oven comprising: - a stationary structure (12) defining a cavity (14) having a front opening (16), the stationary structure (12) having a frame (18) which surrounds said front opening (14), - a door (20) hinged on one side (18h) of said frame and movable between an open position and a closed position, - at least one lighting device (38) arranged to light said cavity (14), and - a door cooling system (26) comprising a fan (28) borne by the stationary structure (12) and a cooling space (30) integrated in the door (20), in which the air flow produced by said fan (28) is conveyed into said cooling space (30) in the closed position of the door (20), wherein said lighting device (38) is fitted to said frame (18), is arranged to direct the light radiation toward said cavity (14), and is struck by at least a part of the cooling air flow produced by said fan (38).

Description

SPECIFICATION of the industrial invention entitled:

AN OVEN WITH A COOLED LIGHTING DEVICE by: Illinois Tool Works Inc., a US company, 3600 West Lake Avenue, Glenview, Illinois 60025, USA

Designated inventors: Daniele TURETTA, Andrea GALLUCCI, Massimo PERUZZO

Filed: May 25, 2011

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DESCRIPTION

Field of the Invention

The present invention relates to an oven, and in particular a domestic oven, having a cavity closed by a door that is movable between an open position and a closed position .

More specifically, the invention relates to an oven equipped with a cooling system for the door, to implement the "cool door" function, in order to prevent the door from reaching very high temperatures. The "cool door" is cooled by means of a forced ventilation system using a fan which, in the closed position of the door, makes a flow of cooling air circulate in a cooling space integrated in the door.

Description of the prior art

Ovens with "cool door" functions are widely available commercially. Also available commercially are "cool door" ovens equipped with an LED lighting device.

The use of LED lighting devices to light ovens gives rise to problems in relation to the working temperature of the LEDs . Typically, an LED lighting device is incompatible with the working temperature of an oven.

Commercially available solutions have been proposed, making provision for arranging LED lighting devices on the "cool door" of the oven. The cooling system for the oven door is used to keep the LED lighting device at a temperature compatible with the correct operation of the LEDs .

Documents EP1995522 and WO2007/033938 describe ovens with LED lighting devices arranged on the door.

The main drawback of the known solutions is that the LED lighting devices arranged on the door are incapable of lighting the oven cavity when the door is open.

Scope and summary of the invention

An object of the present invention is to provide an oven with an LED lighting device which can light the oven cavity even when the door is open.

According to the present invention, this object is achieved by an oven having characteristics forming the subject of claim 1.

The claims form an integral part of the teaching administered in relation to the invention.

Brief description of the drawings

The present invention will now be described in detail with reference to the accompanying drawings, given purely by way of non-limiting example, in which:

- Figures 1 and 2 are perspective views of an oven according to the present invention with the door closed and open respectively,

- Figure 3 is a partly cutaway front view of the oven of Figure 1,

- Figure 4 is a cross-section along line IV-IV of Figure 3,

- Figure 5 is a cross-section along line V-V of Figure 3, - Figure 6 is an enlarged detail of the part indicated by arrow VI in Figure 5,

- Figure 7 is a perspective view illustrating a second embodiment of an oven according to the present invention with the door open,

- Figures 8 and 9 are cross-sections along lines VIII- VIII and IX-IX of Figure 7 in the closed-door state,

- Figure 10 is a perspective view illustrating a variant of Figure 7, and

- Figure 11 is a cross-section along line XI-XI of Figure 10 in the closed-door state.

Detailed description of embodiments of the invention

With reference to Figures 1 and 2, the reference 10 indicates a domestic oven according to the present invention. The oven 10 comprises a stationary structure 12 having a generically parallelepipedal shape, defining a cavity 14 having a front opening 16. The stationary structure 12 comprises a frame 18 which surrounds the front opening 16. The frame 18 has a rectangular shape with two vertical sides 18v and two horizontal sides 18h.

The oven 10 comprises a door 20 associated with the front opening 16 of the stationary structure 12. The door 20 is movable between a closed position illustrated in Figure 1 and an open position illustrated in Figure 2. In the solution illustrated, which is the most widespread for domestic ovens, the door 20 is hinged on the stationary structure 12 about a horizontal axis located along the lower horizontal side 18h of the frame 18. The door 20 is usually eguipped with a transparent central portion 22 and is fitted on its outer side with a handle 24.

The oven 10 comprises a door cooling system indicated as a whole by the reference 26. The door cooling system 26 comprises a fan 28 borne by the stationary structure 12 and a cooling space 30 integrated in the door 20. In the embodiment illustrated, the fan 28 is a tangential fan borne by an upper panel 32 of the stationary structure 12. The air flow produced by the fan 28 is sent to a shroud 34. In the closed-door position, the shroud 34 communicates with the cooling space 30 in the door 20 through a plurality of holes 36 formed on the upper edge of the door 20. During operation, the fan 28 produces a cooling air flow which is fed into the cooling space 30 in the door 20. The continuous passage of the air flow in the cooling space 30 maintains the door 20 at a far lower temperature than the working temperature inside the cavity 14. The cooling air flow is discharged to the outside of the cooling space 30 by means of holes provided, for example, along the lower edge of the door 20.

The oven 10 comprises at least one lighting device 38 arranged to light the cavity 14. The lighting device 38 can be an LED device or any other lighting device which reguires cooling. According to the present invention, the lighting device 38 is fitted to the frame 18 and is arranged to direct the light radiation toward the inside of the cavity 14. This arrangement provides for lighting the cavity 14 both in the closed-door state and in the open- door state. The lighting device 38 is struck by at least a part of the cooling air flow produced by the fan 28, in such a way as to maintain the temperature of the lighting device 38 below an operating limit.

With reference to Figure 6, the lighting device 38 comprises a heat sink 40, preferably made of metal, eguipped with one or more slots 42 through which a cooling air flow from the fan 28 passes. The heat sink 40 bears a support 44 made of plastic material which in turn bears at least one printed circuit board 46 having one or more LEDs 48. The support 44 and the printed circuit board 46 can be housed in a cavity 50 of the heat sink 40. The cavity 50 can be closed by a transparent piece 52, for example made of glass .

The shape specification and arrangement of the lighting device 38 may vary depending on the applications. In the example illustrated in Figures 2, 5 and 6, two lighting devices 38 are provided, fitted to respective vertical sides 18v of the frame 18. Each lighting device 38 is extended in a vertical direction. The cooling slots 42 form vertical channels for the passage of a part of the cooling air flow produced by the fan 28. The upper ends of the slots 42 are in communication with the side portions of the shroud 34. A part of the air flow produced by the fan 38 is directed toward the cooling space 30 in the door 20 and a part of the air flow strikes the lighting device 38.

Solutions can also be provided in which the lighting device 38 is struck by the entire cooling air flow produced by the fan 28.

Figures 7 to 9 illustrate a second embodiment of the oven according to the invention. Items corresponding to those described previously are indicated with the same numerical references .

In the embodiment illustrated in Figures 7 to 9, the lighting devices 38 are fitted to the vertical sides 18v of the frame 18 as in the case described previously and have a limited length in the vertical direction. The lighting devices 38 are preferably arranged at the corners of the frame 18. The lighting devices 38 protrude frontwardly from the sides 18v of the frame. As in the case of the embodiment described previously, the lighting device 38 comprises a heat sink 40 eguipped with one or more slots 42 for the passage of a cooling air flow .

The cooling space 30 is eguipped with recessed seats 54 positioned in such a way that when the door is closed, the lighting devices 38 are inserted within the respective seats 54. The depth of the seats 54 is substantially egual to the thickness by which the lighting devices 38 protrude from the sides 18v of the frame 18. The dimensions of the seats 54 and of the lighting devices 38 in the horizontal direction are substantially egual. Practically, the shape and dimensions of the seats 54 are such that in the closed- door state the seats are filled by the respective lighting devices 38.

The edges of the seats 54 are eguipped with holes which in the closed-door state place the internal volume of the cooling space 30 in communication with the slots 42 of the lighting devices 38.

As illustrated in Figure 9, during operation, the cooling air flow enters the cooling space 30 through the holes 36 provided on the upper edge of the door 20. A part of the air flow passes through the slots 42 and cools the lighting devices 38.

Figures 10 and 11 illustrate a variant of Figures 7 and 8. In the version of Figures 7 and 8, the lighting devices 38 have the internal vertical edges substantially aligned with the corresponding vertical edges 18v of the frame 18. In the variant of Figures 10 and 11, the internal vertical edges of the lighting devices 38 protrude inward with respect to the vertical edges 18v of the frame 18. Naturally, the principle of the invention remaining the same, the details of construction and forms of embodiment may be varied widely with respect to that described and illustrated, without thereby departing from the scope of the invention, which scope is defined by the claims that follow.

Claims

1. An oven comprising:

- a stationary structure (12) defining a cavity (14) having a front opening (16), the stationary structure (12) having a frame (18) which surrounds said front opening (14) ,

- a door (20) hinged on one side (18h) of said frame and movable between an open position and a closed position,

- at least one lighting device (38) arranged to light said cavity (14), and

- a door cooling system (26) comprising a fan (28) borne by the stationary structure (12) and a cooling space (30) integrated in the door (20), in which the air flow produced by said fan (28) is conveyed into said cooling space (30) in the closed position of the door (20),

wherein said at least one lighting device (38) is fitted to said frame (18) and is arranged to direct the light radiation toward said cavity (14), said lighting device (38) being struck by at least a part of the cooling air flow produced by said fan (38) .

2. The oven as claimed in claim 1, wherein said lighting device (38) comprises a heat sink (40) eguipped with slots (42) for the passage of said cooling air flow.

3. The oven as claimed in claim 2, wherein said heat diffuser (40) has a cavity (50) in which there is arranged a printed circuit board (46) having at least one LED (48), said cavity (50) being closed by a transparent piece (52) .

4 . The oven as claimed in claim 1, wherein said lighting device (38) is fitted to a vertical side (18v) of said frame (18).

5. The oven as claimed in claim 2, wherein said slots (42) of said heat diffuser (40) communicate at one end with a shroud (34) for circulating the cooling air flow produced by said fan ( 28 ) .

6. The oven as claimed in claim 2, wherein, when the door (20) is closed, said slots (42) of said heat diffuser (40) communicate with the internal volume of said cooling space (30) .

7. The oven as claimed in claim 1, wherein said cooling space (30) is eguipped with at least one recessed seat (54) positioned in such a way that when the door is closed, said at least one lighting device (38) is inserted within said recessed seat (54).

8. The oven as claimed in claim 1, wherein said lighting device is struck by the entire air flow produced by said fan ( 28 ) .