WO2022194550A1

WO2022194550A1 - Gas stove

Info

Publication number: WO2022194550A1
Application number: PCT/EP2022/055246
Authority: WO
Inventors: Emilio Placer Maruri; Mario VELO BEZANILLA
Original assignee: BSH Hausgeräte GmbH
Priority date: 2021-03-18
Filing date: 2022-03-02
Publication date: 2022-09-22

Abstract

A gas stove (1), comprising a gas burner (2 – 6), a gas valve (18 – 22) for controlling a flow of combustion gas to the gas burner (2 – 6), a thermocouple (8 – 12) for monitoring the gas burner (2 – 6), a ground (26), wherein the thermocouple (8 – 12) is electrically connected to the ground (26), and a timer device (28) for electrically disconnecting the thermocouple (8 – 12) from the ground (26) after a preset time period to switch off the gas burner (2 – 6) by closing the gas valve (18 – 22).

Description

Gas stove

The present invention relates to a gas stove.

A gas stove comprises gas burners and gas valves. Each gas valve is assigned to one gas burner. Each gas burner has a thermocouple for flame monitoring. Each thermocouple is electrically connected to a ground of the gas stove via a ground wire. By means of phase wires, the thermocouples are connected to magnet units of the gas valves. The thermocouples power the magnet units. As soon as one of the gas burners expires, the assigned thermocouple cools down and the magnet unit is not powered any more. The magnet unit thus closes the assigned gas valve and thus prevents combustion gas from streaming out in the environment. To switch off the gas burners after a preset time period, a timer can be provided that is interposed into the phase wires.

It is one object of the present invention to provide an improved gas stove.

Accordingly, a gas stove is provided. The gas stove comprises a gas burner, a gas valve for controlling a flow of combustion gas to the gas burner, a thermocouple for monitoring the gas burner, a ground, wherein the thermocouple is electrically connected to the ground, and a timer device for electrically disconnecting the thermocouple from the ground after a preset time period to switch off the gas burner by closing the gas valve.

By providing the timer device in the electrical connection to the ground instead of interposing it in a phase wire, a less complex design of the gas stove can be achieved.

The gas stove is a household appliance or part of a household appliance. The gas stove can thus be named household gas stove. The number of gas burners, gas valves and thermocouples is arbitrary. "Monitoring" in this context means flame monitoring. In other words, when a flame of the gas burner expires, the thermocouple cools down. A magnet unit of the gas valve, which is powered by means of the thermocouple when the thermocouple is heated up by the flame, then closes the gas valve and thus prevents unburnt combustion gas from leaving the gas burner.

The ground can be a housing of the gas stove. The ground is preferably electrically connected to the gas valve, in particular to a housing of the gas valve. The thermocouple can be electrically connected to the ground by means of a ground wire. Preferably, the thermocouple is connected to the magnet unit by means of a phase wire. The thermocouple, the phase wire, the ground wire and the ground form an electric circuit. "Electrically disconnecting" in this context means that the timer device is designed to break the electric connection between the thermocouple and the ground. When the electric connection is broken, the magnet unit is not powered any more by the thermocouple and closes the gas valve. The time period can be preset by a user. The preset time period can be arbitrarily selected by the user.

According to an embodiment, the gas valve comprises a magnet unit for closing the gas valve, wherein the thermocouple is electrically connected to the magnet unit via a phase wire.

The magnet unit can comprise a coil and a magnet. Each gas valve has a magnet unit.

According to a further embodiment, the thermocouple is electrically connected to the ground via a ground wire, wherein the timer device is interposed in the ground wire.

The timer device can thus electrically break the ground wire. The timer device is electrically connected to the ground wire.

According to a further embodiment, the timer device comprises a timer and a switch which is controlled by means of the timer.

The timer can be a clock or the like. Preferably, the timer counts down the preset time period after the user starts the timer.

According to a further embodiment, the timer opens the switch after expiration of the preset time period.

In an initial state, the switch is closed. After the preset time period, the timer actuates the switch to open ist.

According to a further embodiment, the gas stove comprises a switch device for electrically connecting the thermocouple either directly to the ground or to the timer device. "Directly" to the ground in this context means that the switch device is connected to the ground via a wire.

According to a further embodiment, the switch device has a first outlet, which is electrically connected to the ground, and a second outlet which is electrically connected to the timer device.

Thus, the switch device has only two or exactly two outlets. This helps to reduce the complexity of the design of the switch.

According to a further embodiment, the gas stove comprises a plurality of gas burners, a plurality of gas valves, wherein each gas valve is assigned to one gas burner, and a plurality of thermocouples, wherein each thermocouple is assigned to one gas burner, and wherein the switch device is designed to electrically connect one or more than one thermocouple either directly to the ground or to the timer device.

For example, there are provided four or five gas burners, gas valves and thermocouples. By means of the switch device, it is possible to choose the gas burner or the gas burners that are meant to expire after the preset time period.

According to a further embodiment, each thermocouple has a ground wire which is electrically connected to a contact of the switch device.

The number of contacts is the same as the number of ground wires.

According to a further embodiment, the switch device is designed to electrically connect each contact either directly to the ground or to the timer device.

The switch device has a housing that encloses the contacts.

Further possible implementations or alternative solutions of the invention also encompass combinations - that are not explicitly mentioned herein - of features described above or below with regard to the embodiments. The person skilled in the art may also add individual or isolated aspects and features to the most basic form of the invention. Further embodiments, features and advantages of the present invention will become apparent from the subsequent description and dependent claims, taken in conjunction with the accompanying drawings, in which:

Fig. 1 shows a schematic top view of an embodiment of a gas stove;

Fig. 2 shows a schematic view of an embodiment of a gas valve arrangement for the gas stove according to Fig. 1;

Fig. 3 shows another schematic view of the gas valve arrangement according to Fig. 2; and

Fig. 4 shows another schematic view of the gas valve arrangement according to Fig. 2.

In the Figures, like reference numerals designate like or functionally equivalent elements, unless otherwise indicated.

Fig. 1 shows a schematic top view of an embodiment of a gas hob or gas stove 1. The gas stove 1 can be a household appliance or part of a household appliance. The gas stove 1 comprises a plurality of gas burners 2 to 6. The number of gas burners 2 to 6 is arbitrary. As Fig. 1 shows, there can be provided five gas burners 2 to 6. The gas burners 2 to 6 protrude over a top sheet 7 of the gas stove 1. The top sheet 7 can be a glass or glass ceramic plate. However, the top sheet 7 can also be a steel sheet. Each gas burner 2 to 6 has a thermocouple 8 to 12 for flame monitoring. The thermocouples 8 to 12 protrude over the top sheet 7. In use of the gas burners 2 to 6, the thermocouples 8 to 12 are heated.

The gas stove 1 has a plurality of knobs 13 to 17. Each knob 13 to 17 belongs to a gas valve 18 to 22. The gas valves 18 to 22 are arranged below the top sheet 7. The number of knobs 13 to 17 is the same as the number of gas burners 2 to 6. Each knob 13 to 17 is assigned to one gas burner 2 to 6. By means of the knobs 13 to 17 and the gas valves 18 to 22, a stream of combustion gas from a main gas pipe to the assigned gas burner 2 to 6 can be controlled continuously or stepwise.

Fig. 2 shows a schematic view of an embodiment of a gas burner arrangement 23. Each gas valve 18 to 22 is part of the gas burner arrangement 23. However, in the following, only the gas valve 18 will be referred to. Besides the gas valve 18 and the gas burner 2 (not shown), the gas burner arrangement 23 comprises the thermocouple 8. The thermocouple 8 is electrically connected to a magnet unit 24 of the gas valve 18 by means of a phase wire 25. The thermocouple 8 is also electrically connected to a ground 26 by means of a ground wire 27. The ground 26 is electrically connected to the gas valve 18, in particular to a housing of the gas valve 18. An electrical circuit is formed by means of the thermocouple 8, the gas valve 18, the phase wire 25, the ground wire 27 and the ground 26.

The gas burner arrangement 23 further has a timer device 28 that is interposed into the ground wire 27 to break the electrical connection between the thermocouple 8 and the ground 26 after a predetermined or preset time period. The timer device 28 has a timer 29, preferably in the form of a clock, and a switch 30 to break the connection between the thermocouple 8 and the ground 26.

The functionality of the gas burner arrangement 23 will be explained in the following. The switch 30 is in an initial state and is thus closed (dotted line). The gas valve 18 is actuated by means of the knob 13. This can be done by pressing down and turning the knob 13. The gas valve 18 is opened and a flow of combustion gas is directed to the gas burner 2 where it is ignited by means of a spark plug (not shown). The spark plug can be powered by pressing down the knob 13.

As soon as the combustion gas is ignited, the thermocouple 8 gets heated up by a flame of the gas burner 2. The thermocouple 8 powers the magnet unit 24 via the phase wire 25. The magnet unit 24 keeps the gas valve 18 open so that the knob 13 can be released. A flow of combustion gas keeps running to the gas burner 2 and keeps the gas burner 2 burning.

When the flame expires, the thermocouple 8 cools down. The magnet unit 24 is not powered any more. Thus, the magnet unit 24 closes the gas valve 18 so that no unwanted flow of combustion gas into the environment occurs.

The functionality of the timer device 28 will be explained in the following. As mentioned before, the switch 30 is closed in an initial state (dotted line). The gas valve 18 is open and the gas burner 2 is burning so that the thermocouple 8 gets heat and powers the magnet unit 24 to keep the gas valve 18 open. Then a predetermined time period, for example 30 seconds, is set at the timer 29. After the time period has expired, the switch

30 opens so that the electrical connection between the thermocouple 8 and the ground 26 is interrupted. The magnet unit 24 is not powered anymore so that the gas valve 18 closes and the flame at the gas burner 2 expires.

Fig. 3 shows another schematic view of the gas burner arrangement 23. Each gas valve 18 to 22 is connected to the assigned thermocouple 8 to 12 by means of a phase wire 25,

31 to 34. Each thermocouple 8 to 12 has a ground wire 27, 35 to 38 that is connected to a switch device 39. The switch device 39 is connected to the ground 26 via a wire 40. The timer device 28 is connected to the ground 26 via a wire 41. The switch device 39 is connected to the timer device 28 via a wire 42.

Fig. 4 shows another schematic view of the gas burner arrangement 23. The switch device 39 has a housing 43 that encloses a plurality of contacts 44 to 48. The contacts 44 to 48 are electrically connected to the ground wires 27, 35 to 38. Each ground wire 27, 35 to 38 has its own contact 44 to 48. The switch device 39 has only two outlets 49, 50. A first outlet 49 is directly connected to the ground 26 via the wire 40. A second outlet 50 is connected to the timer device 28 via the wire 42. By means of the switch device 39 it is possible to electrically connect each ground wire 27, 35 to 38 either to the first outlet 49 and thus directly to the ground 26 or to the second outlet 50 and thus to the timer device 28.

In use of the gas stove 1 , the user choses by means of the switch device 39 which of the gas burners 2 to 6 should be switched off after the preset or predetermined time period by means of the timer device 28. More than one gas burner 2 to 6 can be chosen. The switch device 39 thus connects the ground wire 27, 35 to 38 of the chosen gas burner 2 to 6 to the second outlet 50 and thus to the timer device 28. After expiration of the preset or predetermined time period, the switch 30 of the timer device 28 is opened and the chosen gas burner 2 to 6 is switched off as explained before by electrically disconnecting the assigned thermocouple 8 to 12 from the ground 26.

By means of the gas burner arrangement 23 and the switch device 39, the complexity of the system is reduced. Also, the number of connections and the probability of misconnections is reduced. The complexity of the switch device 39 itself is reduced. The size of the connections is reduced. It is easier to make different switch devices 39 for gas stoves 1 with different numbers of gas valves 18 to 22. It is possible to use the timer device 28 for more than one gas burner 2 to 6 at the same time.

Although the present invention has been described in accordance with preferred embodiments, it is obvious for the person skilled in the art that modifications are possible in all embodiments.

Reference Numerals:

1 gas stove

2 gas burner

3 gas burner

4 gas burner

5 gas burner

6 gas burner

7 top sheet

8 thermocouple

9 thermocouple

10 thermocouple

11 thermocouple

12 thermocouple

13 knob

14 knob

15 knob

16 knob

17 knob

18 gas valve

19 gas valve

20 gas valve

21 gas valve

22 gas valve

23 gas burner arrangement

24 magnet unit

25 phase wire

26 ground

27 ground wire

28 timer device

29 timer

30 switch

31 phase wire

32 phase wire

1 33 phase wire

34 phase wire

35 ground wire

36 ground wire

37 ground wire 38 ground wire

39 switch device

40 wire

41 wire

42 wire 43 housing

44 contact

45 contact

46 contact

47 contact 48 contact

49 outlet

50 outlet

2

Claims

1. A gas stove (1), comprising a gas burner (2 - 6), a gas valve (18 - 22) for controlling a flow of combustion gas to the gas burner (2 - 6), a thermocouple (8 - 12) for monitoring the gas burner (2 - 6), a ground (26), wherein the thermocouple (8 - 12) is electrically connected to the ground (26), and a timer device (28) for electrically disconnecting the thermocouple (8 - 12) from the ground (26) after a preset time period to switch off the gas burner (2 - 6) by closing the gas valve (18 - 22).

2. The gas stove according to claim 1 , wherein the gas valve (18 - 22) comprises a magnet unit (24) for closing the gas valve (18 - 22), and wherein the thermocouple (8 - 12) is electrically connected to the magnet unit (24) via a phase wire (25, 31 - 34).

3. The gas stove according to claim 1 or 2, wherein the thermocouple (8 - 12) is electrically connected to the ground (26) via a ground wire (27, 35 - 38), and wherein the timer device (28) is interposed in the ground wire (27, 35 - 38).

4. The gas stove according to one of claims 1 - 3, wherein the timer device (28) comprises a timer (29) and a switch (30) which is controlled by means of the timer (29).

5. The gas stove according to claim 4, wherein the timer (29) opens the switch (30) after expiration of the preset time period.

6. The gas stove according to one of claims 1 - 5, comprising a switch device (39) for electrically connecting the thermocouple (8 - 12) either directly to the ground (26) or to the timer device (28).

7. The gas stove according to claim 6, wherein the switch device (39) has a first outlet (49), which is electrically connected to the ground (26), and a second outlet (50) which is electrically connected to the timer device (28).

8. The gas stove according to claim 6 or 7, comprising a plurality of gas burners (2 - 6), a plurality of gas valves (18 - 22), wherein each gas valve (18 - 22) is assigned to one

3 gas burner (2 - 6), and a plurality of thermocouples (8 - 12), wherein each thermocouple (8 - 12) is assigned to one gas burner (2 - 6), and wherein the switch device (39) is designed to electrically connect one or more than one thermocouple (8 - 12) either directly to the ground (26) or to the timer device (28).

9. The gas stove according to claim 8, wherein each thermocouple (8 - 12) has a ground wire (27, 35 - 38) which is electrically connected to a contact (44 - 48) of the switch device (39).

10. The gas stove according to claim 9, wherein the switch device (39) is designed to electrically connect each contact (44 - 48) either directly to the ground (26) or to the timer device (28).

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