WO2021050011A1

WO2021050011A1 - An oven with cooking mode detection device and operation method for the same

Info

Publication number: WO2021050011A1
Application number: PCT/TR2019/050741
Authority: WO
Inventors: Fatih ZUNGOR; Faruk TAS; Metin OZTURK; Mustafa BOZTAS
Original assignee: Mamur Teknoloji Sistemleri Sanayi AS
Current assignee: Mamur Teknoloji Sistemleri Sanayi AS
Priority date: 2019-09-10
Filing date: 2019-09-10
Publication date: 2021-03-18
Anticipated expiration: 2022-03-10
Also published as: EP4058732A1; EP4058732A4

Abstract

The invention relates to an oven comprising a rotatable mode setting knob (50) disposed on a control panel (12); multiple electric heating elements (18, 19) provided inside a cooking chamber (11); a commutator (60) operated by activating and deactivating the electric heating elements (18, 19) to heat the cooking chamber (11) in a predefined combination by mechanical switching when the mode setting knob (50) is rotated in a corresponding selected operation mode (A, B, C) and a temperature adjustment element (20) in connection with the electric heating elements (18, 19) to set inner temperature of the cooking chamber (11). The oven further comprising an electronic control unit (30) is configured to check each output terminal (64) of the commutator (60) to detect a return signal (s2) on the a corresponding output terminal (64) while supplying the commutator (60) a constant electric signal (s1) in a predefined modulation from at least one input terminal (62) in a sampling interval in order to detect selected operation mode (A, B, C).

Description

AN OVEN WITH COOKING MODE DETECTION DEVICE AND OPERATION METHOD

FOR THE SAME

FIELD OF THE INVENTION

The present invention relates to an oven with an electronic controller configured to detect the cooking mode, and the operation method thereof.

BACKGROUND OF THE INVENTION

Cooking chamber temperature of an oven that contains electrical elements such a fan, lighting elements and electric heating elements in a cooking chamber is set through an adjustment switch on a control panel. A thermostat measures the cooking chamber temperature based on the selected temperature, activating and deactivating electric heating elements as necessary.

A cooking mode setting knob on the control panel allows selecting different cooking functions. Different electrical components in the oven are activated in a combination determined by the selected cooking mode. As an economic solution, the cooking setting mode selection is made through mechanical switches connected to a rotating adjustment switch called a commutator. Contact elements attached to the adjustment shaft on the commutator open and close multiple switches based on the shaft's angle of rotation. Mains power is supplied to necessary electrical components in the oven based on the combination of open-closed switches corresponding to the selected cooking mode.

BRIEF DESCRIPTION OF THE INVENTION

The object of the present invention is to detect the operation mode in ovens with mechanical commutators in a simple manner.

To achieve the said objectives, the invention relates to an oven containing a rotatable mode setting knob disposed on a control panel; multiple electrical electric heating elements provided inside a cooking chamber; a commutator operated by activating and deactivating the electrical electric heating elements to heat the cooking chamber in a predefined combination -for example, only the top electric heating element for grill mode or top and bottom electric heating elements together in a cooking mode- by mechanical switching when the mode setting knob is rotated in corresponding selected operation mode and a temperature adjustment element in connection with the electrical electric heating elements to set inner temperature of the cooking chamber. In order to detect the selected operation mode, an electronic control unit is configured to check each output terminal of the commutator to detect a return signal on a corresponding output terminal while supplying the commutator a constant electric signal in a predefined modulation from at least one input terminal in a sampling interval. The electronic control unit, e.g. when a start button is pressed, simply sends an electrical current supplied by a power supply to the input terminal of the commutator in a predefined modulation (for example sinusoidal or flat). The input terminal is the input end of each mechanical switch allocated to each program on the commutator. The input signal provided by electric current fluctuate through the mechanical switch activated by the commutator, reaches to the output terminal of the relevant switch and generate the return signal. The input signal cannot reach the output terminal of inactive mechanical switches. Therefore, the electrical signal returns to the electronic control unit as a return signal from whichever output terminal of the commutator's mechanical switches is supplied with an electrical signal. The electrical control unit checks the presence of return signals, determines the corresponding output terminal for the return signal’s output wire, compares the activated electric heating elements to the predefined records in its memory unit and determines the operation mode. Thus, it can activate a predefined heating profile for the relevant operation mode in order to, for example, increase the operation efficiency. The heating profile is a program relating to the activation duration of the electric heating elements that allows keeping the cooking chamber temperature near the selected values.

In a preferred embodiment, the electronic control unit is provided on the control panel distant from the commutator and comprises an lead wire and output wire from one end connected to the electronic control unit and on the other end to the commutator from the corresponding input terminal and output terminal in electric signal conducting manner to transmit electrical input signal and the return signal respectively. In such a way, a simple configuration modification enables detecting the oven mode in a conventional oven with a mechanical commutator that cannot detect the oven mode.

In a preferred embodiment, the lead wire is connected to each corresponding input terminal on the commutator and the output wire to the corresponding output terminal in series or in parallel manner. Serial or parallel connections allow the input or output terminals to each port of the commutator, i.e. connection ports of the mechanical switch. While connections for each input or output can be established to the electronic control unit terminal through separate lead and output wires, also a single lead and output wire can be adapted. In a preferred embodiment, the electronic control unit is connected to a display configured to show the selected operation mode. The display informs the user regarding the selected mode when the electronic control unit detects the selected operation mode by, for example, displaying a corresponding standard cooking mode icon or a text. The display may be a backlit digital display screen.

In a preferred application of the invention comprises an oven operation mode comprising the following steps: of electronic control unit to generate an input electric signal, detect the presence of the return signal and compare the active mechanical switching pattern with a predefined configuration stored in a memory unit thereof and store detected corresponding operation method information to the memory module. This method allows easy detection of mechanical switches on the commutator which are passing the electrical signal, that is, conducting electricity to the connected electric heating element by analyzing the signal in the electronic control unit. In a possible embodiment, mechanical switches are connected and driving other features with electricity of the oven such as fans and lighting elements, and the electronic control unit detects the operating features.

In a preferred application, the return electronic signal is sinusoidal form, and comprising the step of the electronic control unit to measure the slope of the electronic return signal and determine whether a mechanical switching is carried out based on detection of a wave slope.

In a preferred application, comprising the steps of the electronic control unit to provides energy for a duration selected in accordance with a predefined heating profile determined based on the detected operation mode in order to reach the inner chamber central temperature set through the temperature adjustment element. In this case, economic cooking profiles that increase energy savings can be operated in the oven.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is the schematic frontal view of an oven comprising the cooking mode detection device of the subject matter along with a drawing symbolizing the functional structure of the commutator.

Figure 2 presents graphs showing return signals processed/not-processed by an electronic control unit in the cooking mode detection device of the subject matter invention. DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, the development of the subject matter of the invention has been described without any limitation and only with references to the examples for a better explanation of the subject.

Figure 1 shows the frontal view of an oven (10) with the cooking mode detection device of the present invention and the operation diagram of a mechanical commutator (60) used to set the operation mode (A, B, C) of this oven. The oven (10) contains a confined cooking chamber (11) accessed from the front through a hinged door, and a control panel (12) horizontally disposed on the top. The control panel (12) has a display (14) disposed to in a visually accessible manner from the outside and setting buttons (15) are disposed adjacent to the side of the display (14). An electronic control unit (30) on the back side of the setting buttons (15) and display (14) is attached to the control panel (12) from its back side. The setting buttons (15) and display (14) directly access the electronic control unit (30) in a electric signal conducting manner. The electronic control unit (30) contains a processor (not shown) and a memory module (not shown) that communicate with each other by conducting low voltage electric signals on a printed circuit. An embedded software drives the electronic control circuit (30) and carries out functions such as clock, alarm, etc. depending on the model, and allows the user access to relevant usage information and adjustment parameters through the display (14). The display (14) is a backlit LCD unit.

The control panel (12) has a rotary temperature setting knob (20). The temperature setting knob (20) allows the cooking chamber (11 ) to reach a temperature set by the user, by activating and deactivating the electric heating elements (18, 19) inside the cooking chamber (11 ) through a connected thermostat (not shown).

The control panel (12) also has a rotary mode setting knob (50). The mode setting knob (50) is connected to a mechanical commutator (60) in a manner that change its setting by rotation by means of a shaft. The mechanical commutator (60) is of standard build and contains a cam switch that generates different connection combinations based on the rotation angle between multiple switches moved by a rotating shaft as specified in patent no. EP2938928, hereby incorporated by reference, particularly shown in Figures and described as the control element, and the corresponding metal contacts. The electrical connection diagram of the commutator (60) is shown in Figure 1 . Under normal circumstances, OFF mode (A) is selected on the mode setting knob (50). When OFF mode (A) is selected, no contacts are established between the vertical input terminals (62) of the commutator (60) and corresponding input terminal, and between vertical output terminals (64) and corresponding output terminal. Therefore, a mains current (L) supplied from one of the commutator's (60) corresponding legs and transformed in a transformer (not shown) cannot reach any electrical element in the cooking chamber (11 ).

On the other hand, when the contact between connection terminal indicated as P3 and the opposite terminal no. 1 is rotated to establish a bridge in the first cooking mode (B), an electrical signal is conducted from the input terminal (62) to the corresponding output terminal (64) through two terminal contact. Mains current (L) passes through contact no. 1 and reaches an electric heating element (18) inside the cooking chamber (11). As the selected electric heating element is on top (18), the selected cooking mode is grilling. To switch to another, second cooking mode (C), the mode setting knob (50) is rotated to a second cooking mode (C) position marked by screen printing on the control panel (12), activating the second electric heating element (19). In this case, the selected second cooking mode (C) is the cooking mode in which both top and bottom electric heating elements (18, 19) are activated.

To detect the cooking mode, the electronic control unit (30) that is ON (energized) directs a sinusoidal input signal (si) to the commutator (60) as shown in Figure 2. The input signal (si) reaches the commutator (60) from the input terminal (62) through a connected lead wire (66). The lead wire (66) is connected in a manner that conducts electric signals between the electronic control unit (30) on one end and the corresponding input terminal (62) on the other. On the other hand, an output wire (68) is connected between an output terminal (64) on one end and the electronic control unit (30) on the other in a manner that conducts electric signals in order to provide the return of a return signal (S2) to the electronic control unit (30). In the OFF position (A), the indication mark on the mode setting knob (50) faces upwards. In this case, all switching elements of the commutator (60) are in a non-conducting state as shown in Figure 1 . Therefore, although the electronic control unit (30) conducts the input signal (si), which is a sinusoidal electric signal to the P3 input terminal (62) of the commutator (60) through the lead wire (66), the electronic control unit (30) detects a flat return signal (S2) on corresponding output terminal no. 1 (64). The electronic control unit (30) is configured to detect sinusoidal electric signals. When a flat signal is received from the output wire (68), the electronic control unit (30) generates an OFF mode (A) record and the display (14) informs the user that a selection is not made. When the mode setting knob (50) is set to the first operation mode (A), one of two input terminals of the P3 terminal (62) conducts mains current (L) to the electric heating element (18), while the other conducts the input signal (s1 ) supplied from the electronic control unit (30) in connection with the lead wire (66) to one of two output terminals of terminal no. 1 (64), to which an output wire (68) is connected. Thus, it is returned to the electronic control unit (30) as the return signal (s2). The electronic control unit (30) detects the sinusoidal return signal (s2) by measuring their slopes. The slope detected in the return signal (s2) is converted by the electronic control unit (30) to a digitally interpretable processed return signal (s2a) that indicates the switch (P3, 1) that is activated on the commutator (60). This allows the electronic control unit (30) to match the return signal (s2) to the combination stored in the memory module (for example, P3, 1 top electric heating element, i.e. grill mode) to detect the selected oven mode. The electronic control unit (30) operates the oven according to the cooking profile that is assigned to grill mode (first operation mode (B)) in the memory module. REFERENCE NUMBERS

10 Oven 60 Commutator

11 Cooking chamber 62 Input terminal

12 Control panel 64 Output terminal

14 Display 66 Lead wire

15 Setting button 68 Output wire

16 Function indication area A OFF Mode

17 Lighting element B First operation mode

18 Electric heating element C Second operation mode

19 Second electric heating element 5₁ Input signal

20 Temperature setting knob 52 Return signal 30 Electronic control unit S2_a Processed return signal

40 Signal transmission element P1 .P3 Connection terminal 50 Mode setting knob L Mains current

Claims

1- An oven comprising a rotatable mode setting knob (50) disposed on a control panel (12); multiple electric heating elements (18, 19) provided inside a cooking chamber (11); a commutator (60) operated by activating and deactivating the electric heating elements (18, 19) to heat the cooking chamber (11) in a predefined combination by mechanical switching when the mode setting knob (50) is rotated in a corresponding selected operation mode (A, B, C) and a temperature adjustment element (20) in connection with the electric heating elements (18, 19) to set inner temperature of the cooking chamber (11) characterized in that an electronic control unit (30) is configured to check each output terminal (64) of the commutator (60) to detect a return signal (S2) on a corresponding output terminal (64) while supplying the commutator (60) a constant electric signal (si) in a predefined modulation from at least one input terminal (62) in a sampling interval in order to detect selected operation mode (A, B, C).

2- An oven according to claim 1 , wherein the electronic control unit (30) is provided on the control panel (12) distant from the commutator (60) and comprises an lead wire (66) and output wire (68) from one end connected to the electronic control unit (30) and on the other end to the commutator (60) from the corresponding input terminal (62) and output terminal (64) in electric signal conducting manner to transmit electrical input signal (si) and the return signal (S2) respectively.

3- An oven according to claim 2, wherein the lead wire (66) is connected to each corresponding input terminal (62) on the commutator (60) and the output wire (68) to the corresponding output terminal (64) in series or in parallel manner.

4- An oven according to the preceding claims, wherein the electronic control unit (30) is connected to a display (14) configured to show the selected operation mode (A, B, C).

5- An operation method for an oven according to the preceding claims, comprising the steps of electronic control unit (30) to generate an input electric signal (si), detect the presence of the return signal (S2) and compare the active mechanical switching pattern with a predefined configuration stored in a memory unit thereof and store detected corresponding operation method (A, B, C) information to the memory module.

6- An oven operation method according to claim 5, wherein the electronic return signal (S2) is in sinusoidal form and comprising the step of the electronic control unit (30) to measure the slope of the electronic return signal (S2) and determine whether a mechanical switching is carried out based on detection of a wave slope.

7- An oven operation method according to claims 5-6, comprising the steps of the electronic control unit (30) to provides energy for a duration selected in accordance with a predefined heating profile determined based on the detected operation mode (A, B, C) in order to reach the inner chamber (11) central temperature set through the temperature adjustment element (20).