EP3903042A1

EP3903042A1 - An oven with steam cooking function

Info

Publication number: EP3903042A1
Application number: EP19832977.3A
Authority: EP
Inventors: Erkan GOKMEN; Mehmet Marasli; Vasi Kadir Ertis
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2018-12-27
Filing date: 2019-12-27
Publication date: 2021-11-03
Anticipated expiration: 2039-12-27
Also published as: WO2020136249A1

Abstract

The present invention relates to an oven (1) comprising a cooking cavity (2) which is provided in a casing and wherein the cooking process is performed; at least one tubular heater (5) which heats the air in the cooking cavity (2), which is disposed on the ceiling of the cooking cavity (2) and which is composed of bends (3) and legs (4); a fan (6) which is disposed behind the cooking cavity (2) and which moves the heated air; a water supply line (9) which draws water from a water supply (7) such as water tank or outer water mains by means of a water transfer member (8) such as valve or pump in order to generate steam; and a steam generation pipe (11) with one end connected to the water supply line (9), which is disposed onto the heater (5) so as to contact the upper surface of at least one leg (4) and/or bend (3) of the heater (5), which generates steam with the water taken from the water supply line (9) and which delivers steam into the cooking cavity (2) through a steam outlet orifice (10) provided at the other end thereof.

Description

AN OVEN WITH STEAM COOKING FUNCTION

The present invention relates to an oven which has the steam cooking function.
The ovens with the function of steam cooking are gradually preferred more thanks to advantages such as high capacity thermal energy, efficient heat transfer, prevention of humidity loss on the foodstuff, maintaining vitamin, mineral and folic acid content, prevention of the formation of carcinogenic acrylamide, etc. Steam generators used in steam ovens are systems which spray water on a hot surface, vaporize the water poured to the bottom of the cavity (cooking cavity), or most commonly generate steam by boiling water in a tank outside the cavity and delivering the vapor to the cavity via a pipeline. In embodiments where the steam generator is positioned outside the oven, energy efficiency is reduced due to heat loss to the environment during steam generation. In known steam generators, there is a need for water tank, water level and temperature sensors, steam transmission line, safety system against overheating of the water tank and control systems to ensure the compatibility of all these components
The Patent No. EP1654931 (B1) relates to a steam generator used in a steam oven. The steam generator is composed of a U-shaped pipe having at least one bend and a heater.
In the Patent Application No. WO2013080100 (A1), an oven is disclosed, comprising a steam dispensing conduit which is produced in the same form as the coil-shaped heater.
The aim of the present invention is the realization of an oven wherein instantaneous steam generation is carried out by means of a low-cost steam generation system.
The oven realized in order to attain the aim of the present invention comprises a water supply line which draws water from a water supply such as water tank or outer water mains by means of a water transfer member such as valve or pump in order to generate steam, and a steam generation pipe which is disposed onto the heater so as to contact the upper surface of at least one leg and/or bend of the heater which heats up first, which generates steam with the water taken from the water supply line and which delivers steam into the cooking cavity through a steam outlet orifice provided at the other end thereof.
On the upper or lateral surface of the steam generation pipe, a plurality of side steam outlet holes are opened, which are arranged longitudinally before the steam outlet orifice.
In an embodiment of the present invention, the steam generation pipe comprises a recess which extends longitudinally on the lower surface thereof and which increases the contact surface with the upper surface of the heater.
In another embodiment of the present invention, the heater and the steam generation pipe placed thereon have rectangular cross-sections.
In another embodiment of the present invention, a thermally conductive member produced from a material with high thermal conductivity coefficient is disposed between the heater and the steam generation pipe.
The oven realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 - is the schematic view of the oven of the present invention.
Figure 2 - is the top perspective view of the oven so as to shown the inner volume thereof.
Figure 3 - is the view of detail A in Figure 2.
Figure 4 - is the view of detail B in Figure 2.
Figure 5 - is the perspective view of the heater and the steam generation pipes.
Figure 6 - is the schematic cross-sectional view of the steam generation pipe placed onto the heater and the preheating pipe placed next to the heater.
Figure 7 - is the schematic cross-sectional view of a steam generation pipe with curved lower surface placed onto the heater.
Figure 8 - is the schematic cross-sectional view of a steam generation pipe and a thermally conductive member placed onto the heater.
Figure 9 - is the schematic cross-sectional view of the heater and the steam generation pipe which have rectangular cross-sections.
Figure 10 - is the schematic cross-sectional view of the heater, the steam generation pipe and the water collection pipe which are disposed one above the other.
Figure 11 - is the schematic cross-sectional view of thermally conductive member which surrounds the heater, the steam generation pipe and the water collection pipe which are disposed one above the other.
The elements illustrated in the figures are numbered as follows:

Oven
Cooking cavity
Bend
Leg
Heater
Fan
Water supply
Water transfer member
Water supply line
Steam outlet orifice
Steam generation pipe
Side steam outlet hole
Preheating pipe
Recess
Thermally conductive member
Water collection pipe

The oven (1) comprises a cooking cavity (2) which is provided in a casing and wherein the cooking process is performed; at least one tubular heater (5) which heats the air in the cooking cavity (2), which is disposed on the ceiling of the cooking cavity (2) and which is composed of bends (3) and legs (4); and a fan (6) which is disposed behind the cooking cavity (2) and which moves the heated air.
The oven (1) of the present invention comprises
- a water supply line (9) which draws water from a water supply (7) such as water tank or outer water mains by means of a water transfer member (8) such as valve or pump in order to generate steam, and
- a steam generation pipe (11) with one end connected to the water supply line (9), which is disposed onto the heater (5) so as to contact the upper surface of at least one leg (4) and/or bend (3) of the heater (5), which generates steam with the water taken from the water supply line (9) and which delivers steam into the cooking cavity (2) through a steam outlet orifice (10) provided at the other end thereof.
On the upper or lateral surface of the steam generation pipe (11) which does not contact the heater (5), a plurality of side steam outlet holes (12) are opened, which are arranged longitudinally before the steam outlet orifice (10).
In an embodiment of the present invention, the oven (1) comprises a preheating pipe (13) which is disposed between the water supply line (9) and the steam generation pipe (11), which contacts the lateral surface of the leg (4) of the heater (5) and which heats the water coming from the water supply line (9) before entering the water generation pipe (11), thus accelerating the steam generation.
In the oven (1) of the present invention, in order to generate steam, water is supplied to the steam generation pipe (11) from a water supply (7) such as water tank provided in the oven (1) or water mains by means of a water transfer member (8) such as valve or pump and a water supply line (9). When, the steam is desired to be generated in the oven (1), first the heater (5) is activated and the heater (5) reaches the required temperature (500 - 550°C) in a short time. The steam generation pipe (11) is placed onto the upper surface, "heating up first", of at least one leg (4) of the heater (5) which is placed in the horizontal position at the upper side of the cooking cavity (2). When the heater (5) is energized, heat is quickly transferred to the steam generation pipe (11), and the small volume of water (2 - 5 ml) taken into the steam generation pipe (11) vaporizes in seconds, thus instantaneously generating steam. In an embodiment of the present invention, the water (15 -20°C) supplied to the steam generation pipe (11) is preheated up to, for example, 80 - 100 °C in the preheating pipe (13) or in the first section of the steam generation pipe (11). After being generated, the steam is delivered into the cooking cavity (2) through the multiple side steam outlet holes (12) and/or the steam outlet orifice (10) arranged at the end of the steam generation pipe (11).
In another embodiment of the present invention, the heater (5) has a circular cross-section, and the steam generation pipe (11) comprises a recess (14) which extends longitudinally on the lower surface thereof and which increases the contact surface with the upper surface of the heater (5).
In another embodiment of the present invention, the oven (1) comprises the heater (5) with a rectangular cross-section and the steam generation pipe (11) with a rectangular cross-section placed on the heater (5). In this embodiment, planar contact is provided between the upper surface of the heater (5) and the lower surface of the steam generation pipe (11), thus improving heat transfer.
In another embodiment of the present invention, the oven (1) comprises a thermally conductive member (15) which is wrapped or coated around the steam generation pipe (11), which is formed at the lower surface thereof to increase the contact area with the heater (5), and which is produced from a material with a high thermal conductivity coefficient, such as aluminum, copper or alloys thereof.
In another embodiment of the present invention, the oven (1) comprises a water collection pipe (16) which is positioned above the steam generation pipe (11), which extends at least partially along the steam generation pipe (11), which is fluidly connected to the steam generation pipe (11), which collects splattering water droplets instantaneously heated in the steam generation pipe (11) and which prevents the water droplets from dripping into the cooking cavity (2) through the steam outlet orifice (10) and/or the side steam outlet holes (12).
In another embodiment of the present invention, the heater (5), the steam generation pipe (11) and the water collection pipe (16) are disposed one above the other.
In another embodiment of the present invention, the thermally conductive member (15) surrounds all three of the heater (5), the steam generation pipe (11) and the water collection pipe (16) which are disposed one above the other so as to keep them together, thus transferring heat from the heater (5) to the steam generation pipe (11).
Since the steam generation is performed in the cooking cavity (2) in the oven (1) of the present invention, there is no heat loss to the environment. Since water is supplied to the steam generation pipe (11) only during steam generation, the need for measuring the water level is eliminated. The problems encountered in state of the art steam generation systems such as shaking of water during boiling and improperly measuring the water level are eliminated. The first steam release time is shortened by vaporizing the small amount of water supplied to the steam generation pipe (11). In the oven (1), a low-cost steam generation system is realized in order to carry out steam cooking and to instantaneously generate steam.

Claims

An oven (1) comprising a cooking cavity (2) wherein the cooking process is performed; at least one tubular heater (5) which heats the air in the cooking cavity (2) and which is composed of bends (3) and legs (4); and a fan (6) which is disposed behind the cooking cavity (2), characterized by

- a water supply line (9) which draws water from a water supply (7) by means of a water transfer member (8) in order to generate steam, and

- a steam generation pipe (11) with one end connected to the water supply line (9), which is disposed onto the heater (5) so as to contact the upper surface of at least one leg (4) and/or bend (3) of the heater (5), which generates steam with the water taken from the water supply line (9) and which delivers steam into the cooking cavity (2) through a steam outlet orifice (10) provided at the other end thereof.
An oven (1) as in Claim 1, characterized by a plurality of side steam outlet holes (12) which are opened on the upper or lateral surface of the steam generation pipe (11) which does not contact the heater (5) and which are arranged longitudinally before the steam outlet orifice (10).
An oven (1) as in Claim 1 or 2, characterized by a preheating pipe (13) which is disposed between the water supply line (9) and the steam generation pipe (11), which contacts the lateral surface of the leg (4) of the heater (5) and which heats the water coming from the water supply line (9) before entering the water generation pipe (11).
An oven (1) as in Claim 1 or 2, characterized by the heater (5) which has a circular cross-section, and the steam generation pipe (11) comprising a recess (14) which extends longitudinally on the lower surface thereof and which increases the contact surface with the upper surface of the heater (5).
An oven (1) as in Claim 1 or 2, characterized by the heater (5) with a rectangular cross-section and the steam generation pipe (11) with a rectangular cross-section placed on the heater (5).
An oven (1) as in Claim 1 or 2, characterized by a thermally conductive member (15) which is wrapped or coated around the steam generation pipe (11), which is formed at the lower surface thereof to increase the contact area with the heater (5), and which is produced from a material with a high thermal conductivity coefficient.
An oven (1) as in Claim 1 or 2, characterized by a water collection pipe (16) which is positioned above the steam generation pipe (11), which extends at least partially along the steam generation pipe (11) and which is fluidly connected to the steam generation pipe (11).
An oven (1) as in Claim 7, characterized by the heater (5), the steam generation pipe (11) and the water collection pipe (16) which are disposed one above the other.
An oven (1) as in Claim 7 or 8, characterized by the thermally conductive member (15) which surrounds all the three of the heater (5), the steam generation pipe (11) and the water collection pipe (16).