U.S. patent application number 10/413018 was filed with the patent office on 2006-08-17 for cooking device door.
This patent application is currently assigned to BSH Bosch und Siemens Hausgerate GmbH. Invention is credited to Rainer Lebacher, Klemens Roch, Wolfgang Schnell, Christine Thaller, Michael Wagner, Gerd Wilsdorf.
Application Number | 20060180141 10/413018 |
Document ID | / |
Family ID | 7659562 |
Filed Date | 2006-08-17 |
United States Patent
Application |
20060180141 |
Kind Code |
A1 |
Schnell; Wolfgang ; et
al. |
August 17, 2006 |
Cooking device door
Abstract
A cooking device door having a viewing window on the side facing
the cooking area located in the housing of the cooking device. The
viewing window completely covering the cooking area opening and
forming a contact surface with a contact flange formed surrounding
the cooking area. The viewing window including a recess in at least
one area oriented in the direction of the cooking area.
Inventors: |
Schnell; Wolfgang;
(Trostberg, DE) ; Wagner; Michael; (Grabenstatt,
DE) ; Lebacher; Rainer; (Palling, DE) ; Roch;
Klemens; (Trostberg, DE) ; Thaller; Christine;
(Tengling, DE) ; Wilsdorf; Gerd; (Olching,
DE) |
Correspondence
Address: |
JOHN T. WINBURN
100 BOSCH BOULEVARD
NEW BERN
NC
28562
US
|
Assignee: |
BSH Bosch und Siemens Hausgerate
GmbH
Munich
DE
|
Family ID: |
7659562 |
Appl. No.: |
10/413018 |
Filed: |
April 14, 2003 |
Current U.S.
Class: |
126/200 ;
126/19R |
Current CPC
Class: |
F24C 15/04 20130101 |
Class at
Publication: |
126/200 ;
126/019.00R |
International
Class: |
F24C 15/04 20060101
F24C015/04 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 12, 2000 |
DE |
10050609.7 |
Claims
1-13. (canceled)
14. A cooking device door for covering an opening in a cooking area
located in a housing of a cooking device, comprising: a viewing
window on a side facing said cooking area, said viewing window
completely covering an opening in the cooking area when the door is
shut and forming a contact surface with a contact flange formed
adjacent said cooking area; said viewing window including at least
one recess formed therein in at least in one area of said window;
and said recess extending into said cooking area when said door is
shut.
15. The cooking device door according to claim 14, including said
viewing window having a single recess which extends over a major
portion of said cooking area opening.
16. The cooking device door according to claim 15, including said
recess having a distance along the sides thereof of less than four
millimeters from said contact flange.
17. The cooking device door according to claim 15, including said
recess having a distance along the bottom thereof of less than four
millimeters from said contact flange.
18. The cooking device door according to claim 15, including said
recess having a distance along the top thereof of less than six
millimeters from said contact flange.
19. The cooking device door according to claim 14, including said
recess having a depth of between and thirty-five millimeters.
20. The cooking device door according to claim 14, including said
recess having flanks with angles between fifty-five and ninety
degrees.
21. The cooking device door according to claim 14, including said
viewing window being thermally pre-stressed.
22. The cooking device door according to claim 14, including said
viewing window being formed of borosilicate glass.
23. The cooking device door according to claim 14, including said
recess having at least one substantially flat area.
24. The cooking device door according to claim 14, including a
second viewing window located on the side of the first viewing
window opposite said cooking area, said second viewing window
including a recess oriented in the direction facing away from said
cooking area.
25. A cooking device with a cooking area located in a device
housing, which cooking area has an opening closable by a cooking
device door, comprising: the cooking device door including a
viewing window on a side facing the cooking area and substantially
covering the opening; said opening including a contact flange
around said opening and said viewing window forming a contact
surface with said contact flange; and said viewing window including
a recess in at least one area oriented in the direction of said
cooking area.
26. The cooking device according to claim 25, including a thermal
self-cleaning unit located within said device housing.
27. The cooking device according to claim 25, including said
viewing window having a single recess which extends over a major
portion of said cooking area opening.
28. The cooking device according to claim 27, including said recess
having a distance along the sides thereof of less than four
millimeters from said contact flange, a distance along the bottom
thereof of less than four millimeters from said contact flange and
a distance along the top thereof of less than six millimeters from
said contact flange.
29. The cooking device according to claim 25, including said recess
having a depth of between and thirty-five millimeters.
30. The cooking device according to claim 25, including said recess
having flanks with angles between fifty-five and ninety
degrees.
31. The cooking device according to claim 25, including said
viewing window being thermally pre-stressed.
32. The cooking device according to claim 25, including said
viewing window being formed of borosilicate glass.
33. The cooking device according to claim 25, including a second
viewing window located on the side of the first viewing window
opposite said cooking area, said
Description
[0001] The invention relates to a cooking device door according to
the preamble of claim 1.
[0002] Cooking devices generally have a cooking area located in a
housing which can be closed using a cooking device door. DE 196 38
241 A1 discloses a cooking device and specifically a baking oven
with a genre-forming cooking device door having a viewing window,
made of glass ceramic for example, on the side oriented in the
direction of the cooking area. The viewing window completely covers
an opening of the cooking area and forms a contact surface with a
contact flange or extends beyond a seal. Such viewing windows are
also called full-surface viewing windows. A metal frame
encompassing the viewing window can be dispensed with and dirty
edges caused thereby on the inside of the viewing window facing the
cooking area can be avoided. In addition, a large field of view can
be achieved.
[0003] A disadvantage however, is that as a result of transverse
heat conduction inside the viewing window, heat and therefore
thermal energy can be transferred from the cooking area outwards
via the contact surface. This firstly results in a loss of heat and
secondly, in cooking devices with a pyrolytic self-cleaning unit,
this can lead to residual contamination in the area of the contact
surface between the viewing window and the contact flange and
specifically because as a result of the transverse heat conduction,
the temperature of the viewing window decreases to such an extent
in the direction of transverse heat conduction to the contact
surface that the temperature falls below that required for the
pyrolysis process in this area. In order to reduce the transverse
heat conduction in the area of the contact surface, cooking devices
are known wherein the housing of the cooking device is heated by
additional heating elements in the area of the contact surface of
the cooking device door. Another disadvantage is that full surface
viewing windows according to the prior art are made of high-quality
special glasses, e.g. glass ceramic in order to avoid fracture of
the glass as a result of high thermal stresses during pyrolytic
operation.
[0004] The object of the invention is to further develop a generic
cooking device door and specifically an advantageous thermal
insulation should be achieved with a design that is both simple and
space saving.
[0005] The object is achieved according to the invention by the
features of claim 1 while advantageous developments and refinements
of the invention can be deduced from the dependent claims.
[0006] The invention relates to a cooking device door which has a
viewing window on the side facing towards a cooking area which is
located in a housing of a cooking device, said viewing window
completely covering an opening of the cooking area and forming a
contact surface with a contact flange.
[0007] It is proposed that the viewing window has a recess oriented
in the direction of the cooking area, at least in one area.
Advantageous thermal insulation in the inner hot area can be
achieved by means of an enlarged insulating space or window
distance in an overall especially space-saving design. Loss of heat
via the cooking device door can be reduced and energy can be
saved.
[0008] The cooking device door according to the invention can also
be used especially advantageously in cooking devices with a thermal
self-cleaning unit. The recess oriented in the direction of the
cooking area can be heated more strongly and an advantageous
cleaning result can be achieved. By means of improved insulation, a
temperature gradient and associated thermal stresses can be reduced
in the area of the recess. In a flank area of the recess in which a
relatively high temperature gradient occurs, a spring effect can be
achieved by sloping flanks by which means stresses in the glass can
be equalised. As a result of the reduced stresses in the area of
the recess and the stress equalisation made possible by the spring
effect, it is possible to use economical materials such as
especially borosilicate glass, soda lime glass etc. However, glass
ceramic could also be used with the loss of the cost advantage.
[0009] The viewing window especially advantageously has only one
recess extending over a major part of the opening of the cooking
area. With a large-area recess, the largest possible area having an
especially advantageous insulation, an especially advantageous
cleaning result in a pyrolysis process and low stresses can be
achieved in a simple design and at low cost. The recess
advantageously has a distance of less than 4 mm at the side and at
the bottom, especially in the case of a cooking device door pivoted
about a lower axis, a distance of less than 6 mm from the contact
flange. An extremely small external area excluded from a pyrolysis
process can be achieved.
[0010] Moreover, especially by means of a smallest possible
distance from the contact flange a labyrinth effect can be achieved
and specifically with regard to dirt constituents and with regard
to heat or hot gases. The outer cooler area can be shielded from
dirt constituents and hot gases whereby contamination of the outer
area can be reduced and burning of dirt constituents in the outer
area can be avoided by a high temperature but not sufficient for a
pyrolysis process. Moreover, low temperatures can be achieved in
the area of the contact flange or in the area of a seal whereby
economical sealing materials can be used, such as especially
silicone etc. Instead of one large recess, it is however
fundamentally also feasible to have a plurality of individual
and/or one ring-shaped recess extending along the contact flange.
Especially by means of recesses extending along the contact flange
and by means of a ring-shaped recess extending along the contact
flange, it is possible to achieve an advantageous labyrinth effect
and a stress-equalising spring effect. In addition to pivoted
cooking device doors, the solution according to the invention can
also be used for sliding oven doors with trays attached, wherein
the recess should be located in the transverse direction within
contact surfaces of hook rails.
[0011] The recess advantageously has a depth between 10 and 35 mm
wherein good insulation can be achieved in this area with an
acceptable space requirement. In particular, especially
advantageous insulation can be achieved with a depth of 35 mm and
the insulation shows merely an insignificant improvement from a
depth of 35 mm. Moreover, the recess advantageously possesses
flanks with an angle between 90.degree. and 55.degree.. An
especially effective labyrinth effect and spring effect can be
achieved with a steep angle.
[0012] In a further development of the invention it is proposed
that the viewing window is pre-stressed and especially by means of
a thermal or chemical process advantageously with a compressive
stress at its surface whereby the strength of the viewing window
can be increased. In the outer cooler region the pre-stress and an
associated high strength can always be maintained especially with
regard to the heat by means of the attainable labyrinth effect.
[0013] The recess can be completely arched or it can advantageously
have at least one flat area whereby this can be produced especially
simply and economically without the view through the viewing window
being affected thereby.
[0014] In order to further enlarge the insulating area or the
distance between the inner viewing window and a second viewing
window adjacent to the viewing window, facing away from the cooking
area, without reducing the size of the cooking area, the second
viewing window can advantageously be designed with a recess
oriented in the direction away from the cooking area.
[0015] The solution according to the invention can be used in
numerous cooking devices which appear logical to the person skilled
in the art, but especially in cooking devices with a thermal
self-cleaning unit, such as especially domestic baking ovens.
[0016] Further advantages are deduced from the following
description of the drawings. An embodiment of the invention is
shown in the drawings. The drawings, the description and the claims
contain numerous features in combination. The person skilled in the
art will more appropriately also consider the features individually
and combine them into logical further combinations.
In the drawings:
[0017] FIG. 1 is a schematic front view of a domestic baking
oven,
[0018] FIG. 2 is a view of a baking oven door of a domestic baking
oven from inside,
[0019] FIG. 3 is a schematic view of a section along the line
III-III in FIG. 1 and
[0020] Figure is a schematic view of a section along the line TV-TV
in FIG. 1.
[0021] FIG. 1 shows a domestic baking oven which has a cooking area
11 in a housing 10. The cooking area 11 is bounded by a muffle 28
and has an opening 13 which is closed with a baking oven door
(FIGS. 3 and 4). On its side facing towards the cooking area 11 the
baking oven door has a viewing window 12 which completely covers
the opening 13 of the cooking area 11 and forms a contact surface
27 with a contact flange 16 of the muffle 28 and specifically with
a silicone seal 29 affixed to the contact flange 16. The contact
surface 27 is shown by a dashed line in FIGS. 1 and 2. The viewing
window 12 can be cleaned by means of an inherently known thermal
self-cleaning unit or pyrolytic unit located in the housing 10 of
the domestic baking oven.
[0022] According to the invention, the viewing window 12 is
constructed as bowl-shaped and has a recess 14 oriented in the
direction of the cooking area 11, which extends over a major part
of the opening 13 of the cooking area 11 and has a distance 15 of 2
mm at the side, a distance 17 of 2 mm at the bottom and a distance
18 of 4 mm at the top from the contact flange 16. As a result of
the small distances 15, 17, 18 from the contact flange 16, there is
an advantageous labyrinth effect towards the outside with respect
to dirt constituents and heat or hot gases. The recess 14 has a
depth 19 of 30 mm and lateral flanks 21 having an angle 23 of
70.degree. and flanks 20 at its top and bottom having an angle 22
of 80.degree.. After its flanks 20, 21 the recess 14 has a flat
area 24 which forms a major part of the recess 14. The viewing
window 12 can additionally have a heat-reflecting coating and/or
suitable printing which specifically impedes the transparency of
the window.
[0023] The recess 14 is moulded onto the viewing window 12. In a
first step the viewing window 12 is placed on a plate having an
indentation corresponding to the recess and is heated in its flank
area by means of heat sources until a flowable state is
established. In a second step the area forming the recess 14 is
then sucked into the indentation of the plate by means of vacuum.
The viewing window 12 is made of borosilicate glass and is
thermally pre-stressed at its surface by means of compressive
stresses.
[0024] In addition to the inner viewing window 12, the baking oven
door has two further viewing windows 25, 30 and specifically a
central viewing window 25 and an outer viewing window 30 facing
away from the cooking area 11. The viewing windows 12, 25, 30 are
held together by means of a support not shown in detail and are
interconnected in an almost airtight fashion by means of plastic
seals 31, 32. The central viewing window 25 has a recess 26
oriented in the direction away from the cooking area 11, having
approximately the same height and width as the recess 14. By means
of the recess 14 and the recess 26 an advantageous insulating space
33 is formed between the viewing disks 12, 25. The central viewing
disk can alternatively also be constructed as completely flat or it
can be omitted if the temperature requirements are reduced.
REFERENCE SYMBOLS
[0025] 10 Housing [0026] 11 Cooking area [0027] 12 Viewing window
[0028] 13 Opening [0029] 14 Recess [0030] 15 Distance [0031] 16
Contact flange [0032] 17 Distance [0033] 18 Distance [0034] 19
Depth [0035] 20 Flank [0036] 21 Flank [0037] 22 Angle [0038] 23
Angle [0039] 24 Area [0040] 25 Viewing window [0041] 26 Recess
[0042] 27 Contact surface [0043] 28 Muffle [0044] 29 Silicone seal
[0045] 30 Viewing window [0046] 31 Seal [0047] 32 Seal [0048] 33
Insulating space
* * * * *