CONTROL ARRANGEMENT WITH TIMER FUNCTION FOR GAS STOVE

Abstract

 The invention relates to a control arrangement (15) for a gas stove (1), the gas stove (1) having a plurality of gas burners (2), wherein a gas supply to each gas burner (2) is normally deactivated and is activatable by at least powering a respective gas control circuit (3), the control arrangement (15) having: a timer unit (16), that is configured to output a timer signal indicating a programmable duration, and a selection unit (17), that has a timer contact (30), a plurality of burner control contacts (32), and a selection mechanism (24), wherein the timer contact (30) is electrically connected to an output (20) of the timer unit (16), wherein each of the burner control contacts (32) is electrically connected or connectable to a respective one of the gas control circuits (3) of the gas stove (1), and wherein the selection mechanism (24) is configured to electrically connect the timer contact (30) with at least one selected burner control contact (32). The invention also relates to said gas stove (1) comprising said control arrangement (15).

Description

[0001] The present invention relates to a control arrangement for a gas stove. In this case, the gas stove has a plurality of gas burners, wherein a gas supply to each gas burner is normally deactivated and is activatable by at least powering a respective gas control circuit.

[0002] Further, the present invention relates to such a gas stove having a plurality of gas burners and the control arrangement.

[0003] In gas burner arrangements, there is usually a safety feature for preventing emission of gas when the burner is not ignited. For this purpose, often a thermocouple unit is employed, usually in electric connection to a normally closed electromagnetic actuated valve. In one generic variant, a thermocouple's high ohmic resistance in cold state is used by interconnecting the thermocouple unit between an electric power source and an electromagnetic actuator. In another generic variant, a thermocouple's electric generator ability, also known as Seebeck effect, is used by connecting both terminals of a thermocouple unit to both terminals of an electromagnetic actuator. In both arrangements, the thermocouple, when cooling down, breaks an electric current to the electromagnetic actuator of a gas supply valve.

[0004] Users of a gas stove may have the need for a timer function that limits a cooking time of a specifiable gas burner.

[0005] It is one object of the present invention to provide a control unit for a gas stove having a timer function. It is another object of the present invention to provide a gas stove having a timer function.

[0006] Accordingly, a control arrangement for a gas stove is provided. The gas stove has a plurality of gas burners, wherein a gas supply to each gas burner is normally deactivated and is activatable by at least powering a respective gas control circuit. The control arrangement has a timer unit. At least one of the gas control circuits of the gas stove is connected or connectable to an output of the timer unit. Thus, the timer function is implemented by controlling the gas control circuit, which is already present. It is beneficial to include the timer function as an interrupting element in series with a thermocouple for breaking an electric current to a normally closed valve when a time is up.

[0007] The object of the invention is solved by providing the following control arrangement for a gas stove. The gas stove has a plurality of gas burners, wherein a gas supply to each gas burner is normally deactivated and is activatable by at least powering a respective gas control circuit. The control arrangement has a timer unit and a selection unit. The timer unit is configured to output a timer signal indicating a programmable duration. The selection unit has a timer contact, a plurality of burner control contacts, and a selection mechanism. The timer contact is electrically connected to an output of the timer unit. Each of the burner control contacts is electrically connected or connectable to a respective one of the gas control circuits of the gas stove. The selection mechanism is configured to electrically connect the timer contact with at least one selected burner control contact.

[0008] The term that each gas burner is activatable by "at least powering" a respective gas control circuit means a necessary condition. For example, in one configuration the gas burner may be activated only by powering its gas control circuit, whereas in another exemplary configuration the gas burner may be activated by powering its gas control unit and by performing another step. For example, a gas burner may be activated by powering its gas control unit and by igniting gas flowing from the gas burner, for example by powering an ignition circuit.

[0009] The term "gas control circuit" means a means for controlling a flow of gas or gas mixture to the respective gas burner. An exemplary gas control circuit may comprise a normally closed electromagnetic actuatable shut-off valve and a thermocouple connected thereto. Further examples are given below.

[0010] The timer unit is configured to output the timer signal. In an exemplary digital version, the timer unit may once output a signal corresponding to an amount of the programmed duration. In another exemplary digital version, the timer unit may output a digital or analogue signal for the programmed duration. In an exemplary analogue version, the timer unit may output a signal for the programmed duration. In a preferred version, the timer unit may output an electric current and/or electric voltage for the programmed duration.

[0011] Each burner control contact is preferably configured and connected or configured and connectable for transferring a timer signal, that is outputted or output-able from the timer unit, to a gas control circuit. The control arrangement has the selection mechanism which may electrically connect a timer contact to a selected burner control contact. That is, by means of the selection mechanism, a user can select which burner is to be controlled by the timer. The selection mechanism thus offers to a user the advantage that a single timer unit may be set up controlling a selectable gas burner.

[0012] According to an embodiment, the selection mechanism is provided with at least one contact connecting unit. This contact connecting unit may be arranged and configured to perform contacting of the timer contact with a selected burner control contact. Examples include a broad range of preferably electromechanical components including bridging contact units, mechanical switches, and/or semiconductor components.

[0013] According to an embodiment, a rotatable handle may be linked in a driving manner to the selection mechanism. That way, a user may rotate the handle in order to select which burner or which burners of the plurality of burners is/are to be controlled by the timer function of the timer unit. Preferred embodiments include a rotatable knob. In this regard, an electromechanical control arrangement can be provided. For example, a cam mechanism, a slotted link mechanism, a lever mechanism and/or a gear mechanism are preferred options for linking the rotatable handle to the selection mechanism. The handle is beneficial for rigidly driving the selection mechanism.

[0014] According to a further embodiment, the selection unit has a power input contact. That is, according to this option, a selection mechanism for a gas stove with four independent burners has at least six contacts, namely at least one timer contact, at least one power input contact, and at least four burner control contacts. The selection mechanism is preferably configured to electrically connect the power input contact with at least one of the burner control contacts. Preferably, the power input contact is provided as a constant signal source. Having a power input contact enables the selection mechanism to provide each burner control contact with a time-limited signal from the timer unit or with a constant signal via the power input contact.

[0015] Preferably, the timer contact and the power input contact are both configured to transmit a signal having the same current and/or voltage. Put in a more general form, it is preferred that the control arrangement is configured such that a time-limited signal transmittable via the timer contact has the same signal characteristics like a constant signal transmittable via the power input contact. Said "signal characteristics" may refer to a magnitude of voltage and/or current and/or the like.

[0016] According to a further embodiment, the selection mechanism has at least one selection state in which the selection mechanism is configured to electrically connect each burner control contact respectively with either the timer contact or the power input contact. That is, in the selection state or selection states, every burner control contact is connected to one of the timer contact and the power input contact. That way, there can be ensured that the burner control contact/-s that is/are not selected will not be blocked due to a lack of a signal and that the corresponding gas burner/-s remain/-s usable.

[0017] According to a further embodiment, the timer contact has an annular or circular shape and the burner control contacts each have an annular or circular segment shape. According to a preferred embodiment, the timer contact is of an annular shape and the burner control contacts are of an annular segment shape. According to another preferred embodiment, the timer contact is of circular shape and the burner control contacts are of annular segment shapes. According to another preferred embodiment, the burner control contacts are of circular segment shapes and the timer control contact is of annular shape. According to a further embodiment, the power input contact has an annular or circular shape and the burner control contacts each have an annular or circular segment shape. Preferably, the timer contact has an annular or circular shape, the power input contact has an annular or circular shape, and the burner control contacts each have an annular or circular segment shape. Preferably, the contacts are concentrically arranged. Thus, the contacts can be arranged in rotational order and are reliably switchable.

[0018] According to a further embodiment, the burner control contacts are arranged radially between the power input contact and the timer contact. Thus, a connection to a burner control contact can fast and reliably be switched from the timer contact to the power input contact.

[0019] According to a further embodiment, the burner contacts do not circumferentially overlap. Thus, if the selection mechanism is rotationally selecting the burner control contact, then it is ensured that no more than one gas burner is controlled by the timer function.

[0020] According to a further embodiment, the burner control contacts partially circumferentially overlap. Thus, if the selection mechanism is rotationally selecting the burner control contact, there can be rotational positions where exactly one of the gas burners is controlled by the timer function, and there can be rotational positions where more than one of the gas burners are controlled by the timer function.

[0021] According to a further embodiment, the selection mechanism is configured to electrically engage and to electrically disengage at least one and preferably each of the burner control contacts with the timer contact and/or power input contact.

[0022] The object of the invention can also be solved by a gas stove. The gas stove has the control arrangement as described above and a plurality of gas burners. A gas supply to each gas burner is normally deactivated and is activatable by at least powering a respective gas control circuit. Each of the burner control contacts is electrically connected to a respective one of the gas control circuits. This gas stove is independently claimable. According to this gas stove, a user can select a gas burner to be controlled by the timer function.

[0023] According to a further embodiment, at least one of the gas control circuits is configured in a closed loop having a thermocouple unit and a valve unit. The thermocouple unit is preferably configured and arranged for generating an electric current when the corresponding gas burner is ignited. The valve unit is preferably configured and arranged to control a gas flow to the corresponding gas burner. Preferably, a control unit is interposed in the gas control circuit such that a flow of an electric signal, preferably the electric current generatable by the thermocouple unit, between the thermocouple unit and the valve unit is controllable by the control unit. The control unit is preferably electrically controlled by the respective burner control contact. Preferably, each of the gas control circuits has this closed loop configuration. The closed loop configuration has the advantage that the gas valve does not need to be externally provided with a current for holding it open.

[0024] According to a further embodiment, at least one of the gas control circuits is configured in an open loop having an electric power supply, a thermocouple unit and a valve unit. The thermocouple unit is preferably configured and arranged for generating an electric resistance, the amount of which is lowering when the corresponding gas burner is ignited. The valve unit is preferably configured and arranged to control a gas flow to the corresponding gas burner. Preferably, a control unit is interposed in the gas control circuit such that a flow of an electric signal between the thermocouple unit and the valve unit is controllable by the control unit. The control unit is preferably electrically controlled by the respective burner control contact. Preferably, each of the gas control circuits has this open loop configuration. The open loop configuration has the advantage that the gas valve can be chosen and configured independently from the Seebeck effect's ability to generate electrical current, especially in terms of the amount of electrical current needed for opening the respective valve.

[0025] According to a further embodiment, for each gas burner, an ignition device is provided, which is operable by the control arrangement. That is, the ignition devices can be activated or ignited by the control arrangement. Thus, a user can both ignite each gas burner and program a timer function for one or more of the gas burners by means of the single control arrangement 15. This increases a user comfort.

[0026] According to a further embodiment, an ignition device is provided separate from the control arrangement. That way, a user can control an ignition of a gas burner in a known and used way, increasing confidence in the safety of the gas stove.

[0027] 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.

[0028] 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 gas stove having a control arrangement according to a first embodiment of the invention; and

Fig. 2 shows a gas stove having a control arrangement according to a second embodiment of the invention.

[0029] In the Figures, like reference numerals designate like or functionally equivalent elements, unless otherwise indicated.

[0030] Fig. 1 shows a gas stove 1 according to a first embodiment of the invention. The gas stove 1 has, for example, four gas burners 2, of which only one gas burner 2 is shown for the sake of easier depiction.

[0031] The gas stove 1 has a gas control circuit 3 associated with the gas burner 2. The gas control circuit 3 is configured and arranged to control a gas supply to a burner head 4 of the gas burner 2. The gas control circuit 3 preferably has a thermocouple unit 5, a control unit 6, and a valve unit 7.

[0032] The valve unit 7 preferably has a normally closed valve device 8 and an electromagnetic actuator unit 9 arranged to open or at least to hold open the valve device 8. If the valve device 8 is closed, a flow of gas G from a gas pipe 10 to the burner head 4 is shut off, thus preventing leaking of gas. If the valve device is opened, a flow of gas G from the gas pipe 10 to the burner head 4 is released, thus enabling a user to cook a dish.

[0033] A power supply 11, the thermocouple unit 5, the control unit 6, the actuator unit 9, and a power supply 11 are electrically connected in series in the first embodiment. Thus, the control unit 6 is arranged and interconnected to control an electric power supply to the actuator unit 9.

[0034] It is to be noted that the "power supply" in terms of voltage, polarity and/or current, for example, depends on the components used and the design of the circuitry. Thus, the generic term "power supply" is used in this description without distinction.

[0035] The gas stove 1 also has a control arrangement 15. The control arrangement 15 in this case has a timer unit 16 and a selection unit 17.

[0036] Fig. 1 shows an exemplary version of the timer unit 16 having a timer device 18 and a program interface 19. The program interface 19 is configured and arranged to control a timer function of the timer device 18. The timer device 18 is configured and arranged to output a timer signal from a timer output 20. For example, the timer device 18 is connected to a power supply 11 and is configured to provide power from the power supply 11 to the timer output 20 for a duration programmed by or given from the program interface 19.

[0037] The selection unit 17 of the first embodiment has a contact arrangement 22, a selection interface 23 and a selection mechanism 24.

[0038] The selection interface 23 for example has a rotatable handle 25. The rotatable handle 25 is a knob 26, for example. The selection interface 23 is linked to a rotation device 27.

[0039] The rotation device 27 may take many forms. Just for the sake of an example, the rotation device 27 is illustrated as a shaft 28 having a cam 29. The rotation device 27 is an example for the selection mechanism 24 of the selection unit 17.

[0040] The contact arrangement 22 comprises preferably a timer contact 30, a power input contact 31 and four burner control contacts 32. The contacts 30, 31, 32 are concentrically arranged in a plane with the shaft 28 extending perpendicular to this plane through a center of this concentric arrangement.

[0041] The timer contact 30 is a common timer contact configured and arranged to be connected to each of the burner control contacts 32. The optional power input contact 31 is a common power input contact configured and arranged to be connected to each of the burner control contacts 32. For example, the timer contact 30 and the power input contact 31 are provided in a preferred ring-shape. Other shapes are conceivable, too.

[0042] Each burner control contact 32 is connected to a respective one of the gas burners 2. If the gas stove 1 should comprise an optional oven, then another burner control contact 32 may be provided for the oven's burner or burners or each of the oven's burners respectively.

[0043] Each burner control contact 32 is preferably provided in a ring segment shape. The burner control contacts 32 preferably succeed one another in circumferential direction. The burner control contacts 32 are preferably arranged in a radial direction between the timer contact 30 and the power input contact 31.

[0044] For example, for each burner control contact 32 there is provided a bridge contact device 33. Each bridge contact device 33 is movable between a first position electrically connecting the respective burner control contact 32 with the timer contact 30 and a second position not electrically connecting of breaking an electrical connection between the respective burner control contact 32 with the timer contact 30. Preferably, as in the first embodiment, each bridge contact device 33 is electrically connecting the respective burner control contact 32 with the power input contact 31.

[0045] The bridge contact devices 33 are examples for contact connecting units that are part of the selection mechanism 24. Such contact connecting units may be arranged and configured to perform contacting of the timer contact 30 with a selected burner control contact 32.

[0046] In a preferred example, each bridge contact device 33 is movable in a radial direction of the shaft 28. Thus, when the shaft 28 rotates the cam 29, the cam 29 presses one of the bridge contact devices 33 outwards. That way, the selection mechanism 24 of this exemplary embodiment electrically connects the timer contact 30 to the selected burner control contact 32.

[0047] Further, preferably, each bridge contact device 33 is biased by a (not shown) spring towards the shaft 28. Thus, when the cam 29 presses one of the bridge contact devices 33 outwards, one of the bridge contact devices 33 is connected to the timer contact 30 while the other bridge contact devices 33 are connected to the power input contact 31.

[0048] One variant of selection unit might be configured such that there is at least one selection state, in which a connection for each bridge contact device 33 is defined. Another variant of selection unit might be configured such that there is at least one selection state, in which a connection is defined only for a part of the bridge contact devices 33. In the latter case, it is preferred that the other bridge contact devices neither connect to the timer contact 30 nor to the power input contact 31.

[0049] The timer output 20 is electrically connected to the timer contact 30. A power supply 11 is electrically connected to the power input contact 31. Each of the burner control contacts 32 is electrically connected to a gas control circuit 3 of a respective gas burner 2. Preferably, each of the burner control contacts 32 is electrically connected to a control unit 6 of a gas control circuit 3 of a respective gas burner 2.

[0050] Preferred examples of the control units 6 include relays and transistors, but the control units are not restricted thereto. The control unit 6 is configured and arranged to connect and break an electric connection such that a flow of electricity between the thermocouple unit 5 and the actuator unit 9 is controlled to be selectively enabled or disabled. For example, if the control unit 6 is interconnected between the actuator unit 9 and the power supply 11, a flow of electricity between the thermocouple unit 5 and the actuator unit 9 is controllable by means of controlling the control unit 6.

[0051] For example, the timer signal may be a voltage signal, preferably having a target voltage value. For example, the electric power flowing through the actuator unit 9 holding open the valve device 8 may be an electric current having a target current value.

[0052] In operation, a user may select a gas burner 2 to be controlled by the timer function. The user may first turn the knob 26 in the corresponding rotational position, thereby connecting the respective bridge contact device 33 with both the timer contact 30 and the respective burner control contact 32. Then, the user may program a desired duration, e.g. 90 minutes, by means of the program interface 19. Then, the respective control unit 6 of the gas control circuit 3 of the selected gas burner 2 is supplied with the timer signal for the programmed duration of time. This preferably results in the control unit 6 enabling a flow of electricity between the thermocouple unit 5 and the actuator unit 9. Then, the user may ignite a gas G flowing from the gas burner 2. Then, the thermocouple unit 5 is heating up und in turn is enabling an electrical current flowing through the actuator unit 9. Thus, the valve device 8 is held open.

[0053] When the programmed duration ends, the timer signal stops, which opens the control unit 6, which breaks the electrical current flowing through the actuator unit 9, which closes the valve device 8, which stops gas flowing from the burner head 4.

[0054] If the user should turn the knob 26 before the programmed duration expires, the respective bridge contact device 33 would be disengaged from the timer contact 30, which would also break the timer signal, which would open the control unit 6, which would stop gas flowing from the burner head 4.

[0055] If a flame burning from the burner head 4 should extinguish before the programmed duration expires, the thermocouple 5 would start cooling down, which also would stop electric current flowing to the actuator unit 9. Thus, the control arrangement 15 may be operated safely.

[0056] The second embodiment shown in Fig. 2 differs from the first embodiment shown in Fig. 1 in that the gas control circuit 3 has a closed loop design without any power supply 11. Still, the control unit 6 is able to enable or disable flow of electricity between the thermocouple unit 5 and the actuator unit 9. The remainder of the configuration corresponds to the description given for the first embodiment.

[0057] Another embodiment differs from the above embodiments in that the timer signal is a digital signal. The control unit 6 is preferably provided as an integrated circuit controlled by the timer signal in this case. The remainder of the configuration corresponds to the description given for one of the above embodiments.

[0058] Another embodiment differs from the above embodiments in that the gas control circuit 3 comprises an ignition unit configured and arranged for igniting a gas flowing from the respective burner head 4. Preferably, the ignition unit is controllable by the control arrangement 15. The remainder of the configuration corresponds to the description given for one of the above embodiments.

[0059] 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:

[0060] 

1

gas stove

2

gas burner

3

gas control circuit

4

burner head

5

thermocouple unit

6

control unit

7

valve unit

8

valve device

9

actuator unit

10

gas pipe

11

power supply

15

control arrangement

16

timer unit

17

selection unit

18

timer device

19

program interface

20

timer output

22

contact arrangement

23

selection interface

24

selection mechanism

25

handle

26

knob

27

rotation device

28

shaft

29

cam

30

timer contact

31

power input contact

32

burner control contact

33

bridge contact device

G

gas

Claims

1. Control arrangement (15) for a gas stove (1),

the gas stove (1) having a plurality of gas burners (2), wherein a gas supply to each gas burner (2) is normally deactivated and is activatable by at least powering a respective gas control circuit (3),

the control arrangement (15) having:

a timer unit (16), that is configured to output a timer signal indicating a programmable duration, and

a selection unit (17), that has a timer contact (30), a plurality of burner control contacts (32), and a selection mechanism (24),

wherein the timer contact (30) is electrically connected to an output (20) of the timer unit (16),

wherein each of the burner control contacts (32) is electrically connected or connectable to a respective one of the gas control circuits (3) of the gas stove (1), and

wherein the selection mechanism (24) is configured to electrically connect the timer contact (30) with at least one selected burner control contact (32).

2. Control arrangement (15) according to claim 1, wherein a rotatable handle (25), preferably a rotatable knob (26), is linked in a driving manner to the selection mechanism (24).

3. Control arrangement (15) according to claim 1 or 2, wherein the selection unit (17) has a power input contact (31), and wherein the selection mechanism (24) is configured to electrically connect the power input contact (31) with at least one burner control contact (32).

4. Control arrangement (15) according to claim 3, wherein the selection mechanism (24) has at least one selection state in which the selection mechanism (24) is configured to electrically connect each burner control contact (32) respectively with either the timer contact (30) or the power input contact (31).

5. Control arrangement (15) according to any of claims 1 to 4, wherein the timer contact (30) has an annular or circular shape and the burner control contacts (32) each have an annular or circular segment shape.

6. Control arrangement (15) according to any of claims 3 to 5, wherein the power input contact (31) has an annular or circular shape and the burner control contacts (32) each have an annular or circular segment shape.

7. Control arrangement (15) according to claims 5 and 6, wherein the burner control contacts (32) are arranged radially between the power input contact (31) and the timer contact (30).

8. Control arrangement (15) according to any of claims 5 to 7, wherein the burner control contacts (32) do not circumferentially overlap.

9. Control arrangement (15) according to any of claims 5 to 7, wherein the burner control contacts (32) partially circumferentially overlap.

10. Gas stove (1), having:

a control arrangement (15) according to any of claims 1 to 10, and

a plurality of gas burners (2),

wherein a gas supply to each gas burner (2) is normally deactivated and is activatable by at least powering a respective gas control circuit (3), and

wherein each of the burner control contacts (32) is electrically connected to a respective one of the gas control circuits (3).

11. Gas stove (1) according to claim 10, wherein at least one of the gas control circuits (3), preferably each of the gas control circuits (3), is configured in a closed loop having a thermocouple unit (5) and a valve unit (7), wherein a control unit (6) is interposed in the gas control circuit (3) such that a flow of an electric signal between the thermocouple unit (5) and the valve unit (7) is controllable by the control unit (6), and wherein the control unit (6) is electrically controlled by the respective burner control contact (32).

12. Gas stove (1) according to any of claims 10 and 11, wherein at least one of the gas control circuits (3), preferably each of the gas control circuits (3), is configured in an open loop having an electric power supply (11), a thermocouple unit (5) and a valve unit (7), wherein a control unit (6) is interposed in the gas control circuit (3) such that a flow of an electric signal between the thermocouple unit (5) and the valve unit (7) is controllable by the control unit (6), and wherein the control unit (6) is electrically controlled by the respective burner control contact (32).

13. Gas stove (1) according to any of claims 10 to 12, wherein for each gas burner (2), an ignition device is provided, which is operable by the control arrangement (15).

14. Gas stove (1) according to any of claims 10 to 12, wherein for each gas burner (2), an ignition device is provided separate from the control arrangement (15).

Drawing