WO2012099474A1

WO2012099474A1 - Multi purpose gas burner

Info

Publication number: WO2012099474A1
Application number: PCT/NL2012/050036
Authority: WO
Inventors: Xander Antonius Henricus Maria Gunnewijk; Johannes VERSTEEG
Original assignee: Intell Properties B.V.
Priority date: 2011-01-21
Filing date: 2012-01-23
Publication date: 2012-07-26
Also published as: EP2665969B1; NL2006811C2; ES2564508T3; EP2665969A1

Abstract

The invention relates to a cooking device comprising at least one gas burner assembly (1) and gas supply means. The gas burner assembly comprises an outer burner (2), and an inner burner (3) having a cross section which is smaller than a cross section of said outer burner. The burner further comprises a simmer burner (4) having a cross section which is smaller than the cross section of said inner burner (3). The gas supply means are arranged to supply gas in three different modes. A first being the simmer mode, a second being the Asian wok cooking mode using the simmer burner and the inner burner, and a third being the Western wok cooking mode using the simmer burner and the outer burner which is warming the outer part of the bottom of the pan.

Description

Multi purpose gas burner

The invention relates to a cooking device comprising at least one gas burner assembly. It also relates to a method of cooking using such a cooking device.

The gas wok-burners for cooking appliances that are currently available at the Western market often differ from the type of wok burners used in Asia. This is because the definition of 'wok cooking' differs in different parts of the world. In Asian countries, where the wok is originated, a wok with a round bottom is used for stir frying. A round bottom wok enables the traditional round spatula to pick all the food up at the bottom of the wok and toss it around easily. It is important with this style of wok cooking that the bottom centre of the pan is as hot as possible. As a consequence, most Asian wok burners consist of a circular ring of flames directed inwards to heat up the bottom centre of the pan.

Wok cooking in Western countries is more like frying and often frying-pans are used on a wok burner. It is important with this style of cooking that the bottom of the pan is heated evenly. Therefore most Western wok burners consist of a large circular outer burner and a smaller inner burner which is concentric to the outer burner. The flames of both burners are directed outwards. These burners ensure that the flat bottom of the pan is evenly heated. However, if a user wants to wok with an Asian type of wok pan on such a Western wok burner, the pan will mainly be heated at the side of the wok pan and the bottom centre of the pan will not be heated sufficiently.

It is the object of the present invention to provide a cooking device that can be used for wok cooking using both the Asian type wok pan having a round bottom and the Western frying pan having a flat bottom.

This object is achieved by providing a cooking device comprising at least one gas burner assembly and gas supply means, the gas burner assembly comprising an outer burner, and an inner burner having a cross section which is smaller than a cross section of the outer burner, and a simmer burner having a cross section which is smaller than the cross section of the inner burner, wherein the gas supply means are arranged to switch gas supply between at least three configurations being:

A - gas supply to the simmer burner, B - gas supply to both the simmer burner and the inner burner,

C - gas supply to both the simmer burner and the outer burner.

Switching gas supplies between these three configurations enables a user to easily switch between simmer cooking, Asian type wok cooking, wherein a central part of a pan needs to be heated, and a Western type of wok cooking wherein an outer part of a pan needs to be heated. So depending on the pan used, a particular burner can be lit. The simmer burner is also burning in mode B and C. In mode C the outer burner heats an outer part of the pan, and the simmer burner heats a central part of the pan, resulting in an overall heating of the pan which is favourable when wok cooking in the Western way. When switching from mode C to B, the gas supply is switched from the outer burner to the inner burner. During this switching, the simmer burner continues to burn, and it will help to ignite the inner burner. When switching from mode B to mode C, a flame channel, between the simmer burner and the outer burner, will ignite the outer burner.

The simmer burner may comprise a plurality of outlets directed inwards. In this way the simmer burner flames will be directed towards the centre of the bottom of the pan which is favourable for Asian type wok cooking but which is also useful when cooking in mode C using a pan having a flat bottom.

In an embodiment, the gas burner assembly comprises one or more flame channels arranged to transfer heat and/or flames from the simmer burner to the outer burner. So once the simmer burner is burning, the outer burner will ignite once gas is let through the outer burner. There is no need for a separate ignition near the outer burner.

The outer burner may comprise a plurality of outlets directed outwards. This will result in the heating of an outer portion of the pan which is favourable when using a flat pan for Western type of wok cooking.

In an embodiment, the inner burner comprises a plurality of outlets directed inwards. This will result in a centrally heated pan which is favourable when an Asian type of wok pan is used which has a curved bottom and wherein a central part of the pan needs to be heated the most.

The simmer burner is smaller than the inner burner. Because the output power of a smaller burner is less than that of a bigger outer burner, a better turn down ratio of the burner is achieved. In a particular embodiment, the gas supply means comprise:

- a first solenoid valve to control a gas supply to the inner burner,

- a second solenoid valve to control a gas supply to the outer burner,

- an electrical circuit for controlling at least the first and second solenoid valve, the circuit is arranged to activate only one of the first and second solenoid valve at a time.

The advantage of this embodiment is that the total burner needs only one main connection instead of two or three.

The electrical circuit mentioned above may comprise an electrical switch arranged to short cut a first circuit comprising a coil of the first solenoid gas valve in a first state, and to short cut a second circuit comprising a coil of the second solenoid gas valve in a second state.

The electrical circuit may also comprise an electrical gas tap switch arranged in series with the electrical switch, the electrical gas tap switch being activated by a rotary knob of a gas tap. In this way, when turning the rotary knob, the user simultaneously activates the electrical switch.

In an embodiment, the gas burner assembly comprises a further burner arranged around the outer burner. This further burner may be used to further increase the burner ratio to a higher output which enables a faster cooking process.

In a particular embodiment, the inner burner and the outer burner are concentric circular rings. This results in a point symmetric configuration, which is favourable for regular pans that which bottom is mostly disc shaped.

In an embodiment, the gas supply means comprises:

- a dual outlet gas tap comprising an inlet and two outlets;

- a 3/2 solenoid valve for supplying gas to the inner burner or the outer burner, said 3/2 solenoid valve comprising a gas inlet connected to one of said outlets of said dual outlet gas tap;

- an electrical circuit for controlling said 3/2 solenoid valve, the electrical circuit being arranged to switch said 3/2 solenoid valve from a first state to a second state.

The advantage of this embodiment is that only one solenoid valve is needed instead of two. This saves costs and increases reliability

The electrical circuit mentioned above may comprise an electrical switch arranged to interrupt the circuit in a first state, and to short cut the circuit comprising a coil of the solenoid gas valve in a second state. The invention also relates to a method of cooking using a device as described, the method comprising switching gas supply between at least three configurations being:

A - gas supply to said simmer burner,

B - gas supply to both said simmer burner and said inner burner,

C - gas supply to both said simmer burner and said outer burner.

Further details and advantages of the present invention will become clear to the reader after reading the description of the embodiments described below with reference to the accompanying drawings, in which:

Figure 1 shows a cross sectional view of a gas burner assembly of a cooking device according to an embodiment of the invention;

Figure 2 schematically shows a cross section of a burner base according to an embodiment;

Figure 3 schematically shows a pneumatic diagram of part of the gas burner assembly according to an embodiment;

Figure 4 shows another embodiment of the gas burner assembly wherein a valve body is separated from a burner base;

Figure 5 schematically shows an electrical circuit used to control the solenoid valves according to an embodiment of the invention;

Figure 6 shows a cross section of a wok pan placed above the gas burner assembly of Figure 2;

Figure 7 shows a cross section of a frying pan placed above the gas burner assembly of Figure 2;

Figure 8 shows a cross section of a wok pan placed above the gas burner assembly of Figure 2;

Figure 9 shows a perspective view of a gas valve and a gas tap switch which are used to supply gas to a wok burner according to an embodiment of the invention;

Figure 10 shows a cross section of a burner base according to an embodiment;

Figure 1 1 schematically shows a pneumatic diagram of part of the gas burner according to an embodiment; Figure 12 shows another embodiment of the gas burner wherein a valve body is separated from a burner base;

Figure 13 schematically shows an electrical circuit used to control the solenoid valve according to an embodiment of the invention;

Figure 14 shows a perspective view of the gas tap, gas valve and burner according to an embodiment of the invention;

Figure 15 shows a perspective view the burner of Figure 14 depicting an ignition and flame safety device and a flame channel;

Figure 16 shows a perspective view of the burner according to an embodiment of the invention, having a fourth burner ring.

Figure 1 shows a cross sectional view of a gas burner assembly 1 of a cooking device according to an embodiment of the invention. In this embodiment the gas burner assembly 1 comprises a circular outer burner with a plurality of outlets 2 directed outwards. The outer burner has a first diameter d1 . The burner 1 also comprises a circular inner burner having a second diameter d2 which is smaller than the first diameter d1 , and comprises a plurality of outlets 3 directed inwards. The gas burner assembly 1 also comprises a simmer burner which comprises a plurality of outlets 4 directed inwards. Since, the burners in this embodiment are circular burners, they are also referred to as 'burner rings'. The gas burner assembly 1 in this embodiment comprises a cavity 5 into which gas is lead via the outlets 3, 4 of respectively the inner ring and the simmer ring.

It is noted that the invention is not limited to the use of circular burners, i.e. rings. Also other shapes of burners are possible like oval or hexagonal, etcetera. In those alternatives the outer burner does not have a fixed diameter but it will surround the inner ring and in the presence of a simmer burner, the inner burner will surround the simmer burner. Please note that the rings mentioned above are mostly not positioned in the same plane. So the term 'surrounding' means surrounding when seen from above.

The gas burner assembly 1 comprises a mixture conduit 6 for supplying a gas/air mixture to the outer burner 2, a mixture conduit 7 for supplying a gas/air mixture to the inner burner 3, and a mixture conduit 8 for supplying a gas/air mixture to the simmer burner 4. Figure 2 schematically shows a cross section of a burner base 15 according to an embodiment. The burner base 15 comprises a central gas conduit 16 splitting into a gas conduit 19 for the simmer burner, a gas conduit 17 for the outer burner, and a gas conduit 18 for the inner burner. The burner base 15 also comprises an outer burner valve 20 and an inner burner valve 21 . Furthermore the burner base 15 comprises an outer burner injector 22, an inner burner injector 23 and a simmer burner injector 24.

Figure 3 schematically shows a pneumatic diagram of part of the gas burner assembly according to an embodiment. Gas is supplied via a main gas pipe 30 and a gas valve 31 to a burner pipe 32. The burner pipe 32 is connected to the central gas conduit 16 of the burner base 15, the components of which are schematically drawn in Figure 3. The gas valve 31 , or gas tap 31 , regulates the gas flow to the burner base 15. The gas conduit 19 connects the burner pipe 32 to the simmer burner injector 24. The simmer burner 4 is always on when the gas valve 31 is opened. The gas conduit 17 connects the burner pipe 32 to the outer burner 2 via the solenoid gas valve 20. The gas valve 20 cause outer burner 2 to be on or off. The gas conduit 18 connects the burner pipe 32 to the inner burner 3 via the solenoid gas valve 21 which controls the gas flow in this conduit, thus controlling if the inner burner 3 is burning or not.

Figure 4 shows another embodiment of the gas burner assembly wherein a valve body 41 is separated from a burner base 42. As can be seen from Figure 4, three gas conduits are arranged between the valve body 41 and the burner base 42. An advantage of this embodiment is that due to the separation, the valve body 41 and the burner base 42 can be positioned in a more flexible way. Furthermore, since the valve body is more remote from the base 42 and thus from the gas flames, the risk of overheating the electronic components is decreased.

Figure 5 schematically shows an electrical circuit used to control the solenoid valves 20, 21 according to an embodiment of the invention. The electrical circuit comprises an electrical power source 51 connected to a gas tap switch 52 which is connected to a burner choice switch 53. The gas tap switch 52 may be arranged at the gas valve 31 (gas tap 31 ) so as to be activated when the gas valve 31 is turned by a user as will be described in more detail with reference to Figure 9. In the embodiment of Figure 5 the burner choice switch 53 has two possible states. It can switch so as to connect to a first solenoid coil of the outer ring valve 20, or it can switch so as to connects to a second solenoid coil being the coil of the inner ring valve 21 . It should be clear to the skilled reader that the embodiment of Figure 5 can be modified so as to control more than two gas valves. The gas burner assembly 1 could for example have a primary burner ring (i.e. the simmer ring), a secondary burner ring, a tertiary burner ring and one or more further burner rings. These further burner rings may be arranged outside the outer burner ring but they may as well be arranged inside the outer burner ring.

In the embodiment of Figure 5, the valves 20, 21 are controlled by the gas tap switch 52 and the burner choice switch 53. The gas tap switch 52 determines if one of the inner or outer burner is on and the burner choice switch 53 determines which of those burners is on. The opening of the valves 20, 21 may be controlled by a printed circuit board instead of by the gas tap switch 52 and the burner choice switch 53.

Due to the specific configuration of the gas conduits and the electrical control circuit, the gas burner assembly 1 of Figure 1 can be operated in three different modes. These modes will be discussed below with reference to Figure 6, 7 and 8.

In Figure 6 a wok pan 61 is placed above the gas burner assembly 1 . The burner base 15 is controlled in such a way that gas is only supplied to the simmer burner ring 4. Once ignited, this results in small flames 62 schematically shown in Figure 6. The flames 62 are directed inwards (i.e. towards the centre of the gas burner assembly 1 ) and produce a heat flow 63 which is mainly heating the central part of the base of the wok pan 61 . Due to the dimension of the injector of the simmer ring, the flames 62 will be of moderate size even when the gas valve 31 is fully opened.

Figure 7 shows the same gas burner assembly 1 and burner base 15 as in Figure 6, but here the outer ring valve 20, see Figure 2, is opened. This results in flames 72 directed outwards and mainly heating the outer region of a frying pan 71 . Since the simmer burner is also on, the centre part of the pan 71 will be heated by the simmer burner 4. This way of heating the pan is ideal for Western type of wok cooking as was discussed in the preamble.

In the third situation, shown in Figure 8, the inner ring valve 21 is opened and therefore the gas will flow towards the inner ring outlets 3. This results in flames 82 directed towards the centre of the wok pan 61 situated on top. This way of heating the pan is ideal for Asian type of wok cooking using a wok pan having a curved bottom as was discussed in the preamble. To switch between the two cooking modes the electrical burner choice switch 53 can be switched by e.g. the push of a button arranged on a panel of a cooking plate. Note that the outer and inner burner rings 2, 3 do not burn simultaneously but are switched.

Figure 9 shows a perspective view of the gas valve 31 and the gas tap switch 52 which are used to supply gas to a wok burner according to an embodiment of the invention. In this embodiment the wok burner comprise a simmer burner 91 , an inner burner 92 and an outer burner 93.

The gas valve 31 has a single inlet 30 and a single outlet 32 which is split into the three conduits 17, 18, 19 as shown in Figure 2. The burner base comprises a valve body 97 housing the valves 20, 21 . The gas valve 31 is controlled by a rotary switch 95 which is attached to the gas valve 31 . By turning the rotary switch 95 on the gas valve 31 , the rotary switch 95 will actuate the gas tap switch 52 at a pre-set turning angle. In an embodiment this is achieved by arranging a cam on the rotation axis of the rotary switch, the cam forcing a latch of the gas tap switch 52, not visible in Figure 9. This will open the conduit to the secondary burner being the inner burner ring or the outer burner ring depending on the burner choice switch 53. It should be noted that the principle of switching an electrical switch by turning a rotary switch of a gas tap is not limited to the embodiment described above. It may well be used to regulate dual flame ring burners. A dual ring burner basically consists of two separate burners, a small burner ring and a larger burner ring, forming one burner. The small burner has a range in the lower rate; the larger burner has a range in the higher rate. By operating multiple burner rings, a burner with a very wide operating range is created. To make this range even wider, a triple or multiple flame ring burner could be created. The dual burners which are currently on the market are regulated by a gas tap with a dual outlet. The two outlets are controlled by a single plunger. There are some issues with these dual outlet gas taps. First of all the costs are very high compared to the single outlet gas taps. Furthermore, there is a gap in the gas flow rate of the first and the second outlet. This results in a gap between the maximum power outlet of the first burner and the minimum output of the second burner. Also the number of burner rings regulated by these gas taps is limited to two. Finally the build in dimension of dual outlet gas tap is larger than the single outlet gas tap. A larger dimension of the gas tap will decrease the design possibilities for the gas hob or stove. Figure 10 schematically shows a cross section of a burner base 105 according to an embodiment. The burner base 105 comprises a gas inlet conduits 103 for the simmer burner injector 24, a gas conduit 102 which is connected to a solenoid gas valve 101 having one inlet and two outlets. In a first state the solenoid gas valve 101 closes the conduit 104 to injector 22 and opens the conduit to injector 23. In a second state, the solenoid gas valve 101 closes the conduit to injector 23 and opens conduit 104 which feeds the gas to injector 22. Since the solenoid gas valve 101 has three pneumatic connections and two states, it is also known as a '3/2- solenoid valve'.

Figure 11 schematically shows a pneumatic diagram of part of the gas burner according to an embodiment. Gas is supplied via a main gas pipe 30 and a dual gas valve 1 1 1 to a first burner pipe 1 12 and to a second burner pipe 1 13. The first burner pipe 1 12 connects the first outlet of the dual gas valve to a gas conduit 102 of the burner base 105, the second burner pipe 1 13 connects the second outlet of the dual gas valve to a second gas conduit 103, the components of which are schematically drawn in Figure 1 1 . The dual gas valve 1 1 1 , or dual gas tap 1 1 1 , regulates the gas flow to the burner base 105. The gas conduit 1 13 connects the second burner pipe 103 to the simmer burner injector 24. The simmer burner 4 is always on when the gas valve 1 1 1 is opened. The gas conduit 102 connects the first burner pipe 1 12 to the outer burner 2 and the inner burner 3 via the solenoid gas valve 101 . The solenoid gas valve 101 determines if the gas flows to the outer burner 2 or inner burner 3. An advantage of this embodiment is that only one valve has to be controlled instead of two.

Figure 12 shows another embodiment of the gas burner wherein a valve body 121 is separated from a burner base 122. As can be seen from Figure 12, three gas conduits are arranged between the valve body 121 and the burner base 122. An advantage of this embodiment is that due to the separation, the valve body 121 and the burner base 122 can be positioned in a more flexible way. Furthermore, since the valve body is more remote from the base 122 and thus from the gas flames, the risk of overheating the electronic components is decreased.

Figure 13 shows an electrical diagram of the solenoid gas valve 101 which is controlled by a burner choice switch. The opening of the solenoid gas valve 101 may be controlled by a printed circuit board instead of a switch 131 .

Figure 14 shows a perspective view of the valve body 105 and the dual gas tap 1 1 1 which are used to supply gas to a wok burner according to an embodiment of the invention. In this embodiment the wok burner comprises a simmer burner 91 , an inner burner 92 and an outer burner 93.

The gas valve 1 1 1 has a single inlet 30 and a double outlet 1 12 and 1 13 which are connected to the burner base according to Figure 10. The burner base comprises a valve body 105 housing the valve 101. The solenoid gas valve 101 is controlled by the burner choice switch 131 . The valve connects the burner pipe 1 12 to a first burner in a first state and connects the burner pipe 1 12 to a second burner in a second state when the burner choice switch 131 is activated.

Figure 15 shows a perspective view the burner of Figure 14 depicting an ignition 151 , a flame channel 152 and flame safety device 153. The ignition 151 is activated once the user presses an ignition button [not shown] or switches the dual outlet gas tap 1 1 1 . The ignition 151 , once activated, ignites the gas from the simmer burner 91 . The flames of the simmer burner 91 will ignite the gas of the inner burner 92, or via the flame channel 152, the gas coming out of the outer burner 93. The flame channel may be a channel comprising separate channel outlets to transfer the flames towards the outer burner 93.

Figure 16 shows a perspective view of the burner according to an embodiment of the invention, having a fourth burner ring 161. Adding the fourth burner ring 161 will increase the range of the burner, so a higher turn down ratio is being achieved.

It is emphasized that the present invention can be varied in many ways, of which the alternative embodiments as presented are just a few examples. These different embodiments are hence non-limiting examples. The scope of the present invention, however, is only limited by the subsequently following claims.

Claims

Claims:

1 . Cooking device comprising at least one gas burner assembly (1 ) and gas supply means, said gas burner assembly comprising:

- an outer burner (2), and

- an inner burner (3) having a cross section which is smaller than a cross section of said outer burner, and

- a simmer burner (4) having a cross section which is smaller than the cross section of said inner burner (3),

wherein said gas supply means are arranged to switch gas supply between at least three configurations being:

A - gas supply to said simmer burner,

B - gas supply to both said simmer burner and said inner burner,

C - gas supply to both said simmer burner and said outer burner.

2. Cooking device according to claim 1 , wherein said gas burner assembly comprises one or more flame channels (152) arranged to transfer heat and/or flames from said simmer burner to said outer burner.

3. Cooking device according to claim 1 or 2, wherein said simmer burner comprising a plurality of outlets directed inwards.

4. Cooking device according to any of the preceding claims, wherein said outer burner comprises a plurality of outlets directed outwards.

5. Cooking device according to any of the preceding claims, wherein said inner burner comprises a plurality of outlets directed inwards.

6. Cooking device according to any of the preceding claims, wherein said gas supply means comprise:

- a first solenoid valve to control a gas supply to said inner burner,

- a second solenoid valve to control a gas supply to said outer burner,

- an electrical circuit for controlling at least said first and second solenoid valve, said circuit is arranged to activate only one of said first and second solenoid valve at a time.

7. Cooking device according to claim 6, wherein said electrical circuit comprises an electrical switch arranged to short cut a first circuit comprising a coil of said first solenoid gas valve in a first state, and to short cut a second circuit comprising a coil of said second solenoid gas valve in a second state.

8. Cooking device according to claim 7, wherein said electrical circuit comprises an electrical gas tap switch (52) arranged in series with said electrical switch (53), said electrical gas tap switch (52) being activated by a rotary knob of a gas tap.

9. Cooking device according to any of the preceding claims, wherein said gas burner assembly comprises a further burner (161 ) arranged around said outer burner.

10. Cooking device according to any of the preceding claims, wherein said inner burner and said outer burner are concentric circular rings.

1 1 . Cooking device according to any of claims 1 -5, wherein said gas supply means comprises:

- a dual outlet gas tap (1 1 1 ) comprising an inlet and two outlets;

- a 3/2 solenoid valve (105) for supplying gas to the inner burner or the outer burner, said 3/2 solenoid valve comprising a gas inlet connected to one of said outlets of said dual outlet gas tap (1 1 1 );

12. Cooking device according to claim 1 1 , wherein said electrical circuit comprises an electrical switch (131 ) arranged to interrupt a circuit comprising a coil of the 3/2 solenoid gas valve (105) in a first state, and to short cut the circuit in a second state.

13. Method of cooking using a device as described by any of the preceding claims, said method comprising switching gas supply between at least three configurations being:

A - gas supply to said simmer burner,

B - gas supply to both said simmer burner and said inner burner,

C - gas supply to both said simmer burner and said outer burner.