WO2015097591A2

WO2015097591A2 - Drive circuit for driving a household appliance from a stand-by condition to an operating condition, and household appliance provided with said circuit

Info

Publication number: WO2015097591A2
Application number: PCT/IB2014/066914
Authority: WO
Inventors: Mauro Possanza; Gianluca Viola; Igor FERRETTI; Luca SORRENTINO; Alberto CAMERIN; Simone Tordoni
Original assignee: Indesit Company S.P.A.
Priority date: 2013-12-23
Filing date: 2014-12-15
Publication date: 2015-07-02
Also published as: WO2015097591A3; ITTO20131060A1

Abstract

A drive circuit (100) for driving a household appliance from a stand-by condition to an operating condition, said circuit comprising: an input stage (110) for generating a main signal (MS) representative of a movement of an actuation/selection element (120) of a household appliance (1), said main signal (MS) having a different sign depending on a direction of movement (D1, D2) of said actuation/selection element (120); a first comparator stage (130) for detecting said main signal (MS) when the latter has a given sign and for outputting a corresponding first control signal (CS1); a second comparator stage (140) for detecting said main signal (MD) when the latter has a sign opposite to said given sign and for outputting a corresponding second control signal (CS2); an output stage (150) configured for generating, when it receives said first control signal (CS1) and/or said second control signal (CS2), a corresponding reactivation signal (RS) for driving said household appliance (1) from a stand-by condition to an operating condition.

Description

Drive circuit for driving a household appliance from a standby condition to an operating condition, and household appliance provided with said circuit

DESCRIPTION

[TECHNICAL FIELD]

The present invention relates to a drive circuit for driving a household appliance from a stand-by condition to an operating condition.

The present invention also relates to a household appliance equipped with said drive circuit.

[PRIOR ART]

The recent developments and lower costs of electronic components, along with the need of offering increasingly innovative products to customers, have led to the development of more and more sophisticated household appliances (e.g. ovens, washing machines, television sets, refrigerators, dishwashers) .

Many household appliances on the market today utilise sensors that detect the operating state of the household appliance or physical quantities which are useful or necessary for it to operate correctly. For example, many ovens are equipped with a thermocouple that allows to detect the temperature within the cooking cavity, thus being able to check food cooking.

The increasing use of on-board electronics has led household appliances to use much energy even when they are not operational, i.e. when they are not carrying out their main function, e.g. the cooking function carried out by a oven.

In order to reduce such energy consumption, a stand-by state is known to be used wherein no power is supplied to a part of the on-board electronics, in particular sensors and video or luminous interfaces.

In known household appliances, the exit from stand-by mode is made possible by the user pressing a button, typically a power button.

This results in a reduced simplicity and speed of use of household appliances.

[OBJECTS AND BRIEF SUMMARY OF THE INVENTION ]

It is an object of the present invention to overcome some of the above-mentioned problems of the prior art.

In particular, it is an object of the present invention to enhance household appliances' simplicity and speed of use without substantially increasing stand-by energy consumption.

These and other objects of the present invention are achieved through a household appliance incorporating the features set out in the appended claims, which are intended as an integral part of the present description.

The idea underlying the present invention is to wake-up the household appliance automatically when the user sets a new work program or, in general, moves the actuation/selection element of the same household appliance. In particular, the present invention is directed to the recognition of the movement of said actuation/selection element in both directions in which this element can be moved.

This solution allows for enhanced simplicity and speed of use of the household appliance since, in order to wake-up the household appliance from stand-by, the user is no longer required to press a specific button, but he/she can simply use the appliance as if it was already operating.

According to a first aspect, the invention relates to a drive circuit for driving a household appliance from a stand- by condition to an operating condition, said circuit comprising :

an input stage for generating a main signal representative of a movement of an actuation/selection element of a household appliance, said main signal having a different sign depending on a direction of movement of said actuation/selection element;

- a first comparator stage for detecting said main signal when the latter has a given sign and for outputting a corresponding first control signal;

- a second comparator stage for detecting said main signal when the latter has a sign opposite to said given sign and for outputting a corresponding second control signal;

an output stage configured for generating, when it receives said first control signal and/or said second control signal, a corresponding reactivation signal for driving said household appliance from a stand-by condition to an operating condition .

Preferably said input stage is a differentiator stage.

Preferably, said actuation/selection element can be driven among a plurality of operating positions, said actuation/selection element being associated with a respective electric circuit adapted to generate a corresponding electric signal as a function of the operating position of the actuation/selection element, said input stage being configured for converting said electric signal into said main signal.

Preferably said electric signal has a step waveform, in particular a voltage step waveform.

Preferably said main signal has a pulse waveform, preferably a voltage pulse waveform.

Preferably said first comparator stage includes a first comparator, having a first input for receiving said main signal and a second input for receiving a first reference, said first comparator being configured for generating said first control signal as a function of a comparison between said main signal and said first reference.

Preferably said second comparator stage includes a second comparator, preferably comprising an operational amplifier and having a first input for receiving said main signal and a second input for receiving a second reference, said second comparator being configured for generating said second control signal as a function of a comparison between said main signal and said second reference.

Preferably said reactivation signal is configured for driving a control unit of said household appliance from a stand-by condition to an operating condition.

Preferably said reactivation signal is configured for acting upon a switch included in said household appliance and driving it from a first condition, in which it keeps said household appliance in a stand-by condition, to a second condition, in which it brings said household appliance into an operating condition.

According to a second aspect, the invention relates to a household appliance comprising:

- at least one operating zone;

- one or more actuators, of the electromechanical and/or electro-thermal type, operationally active on said operating zone ;

- a control unit configured for controlling the operation of said one or more actuators;

- at least one actuation/selection element associated with said one or more actuators and/or with said control unit, said actuation/selection element being movable in order to define operating conditions of said household appliance;

- said drive circuit.

Preferably the reactivation signal generated by said drive circuit is configured for driving said control unit from a stand-by condition to an operating condition.

Preferably said household appliance comprises a switch, which can be driven between a first condition, wherein it keeps said household appliance in a stand-by condition, and a second condition, in which it brings said household appliance into an operating condition, said reactivation signal being configured for driving said switch from the first condition to the second condition.

Preferably said household appliance is an oven; said one or more actuators comprise one or more heating elements; said at least one operating zone comprises a cavity heated by said one or more heating elements.

Preferably said actuation/selection element comprises at least one knob associated with said control unit and/or with said one or more heating elements and/or with said fan.

Preferably said al least one knob is movable in order to determine operating conditions of said oven.

Preferably said switch is an electronic switch circuit. Further features and advantages will become more apparent from the following detailed description of a preferred but not exclusive embodiment.

[BRIEF DESCRIPTION OF THE DRAWINGS]

Such a description is supplied hereafter, by way of non- limiting example with reference to the annexed figures, wherein :

- Fig. 1 shows a representative diagram of a drive circuit according to the present invention;

- Fig. 2 and 3 show block diagrams of two embodiments of the operating state of the circuit of figure 1 ;

- Fig. 4 shows an example of household appliance in which the drive circuit of Fig. 1 can be used.

The figures illustrate various aspects and embodiments of the present invention and, where appropriate, structures, components, materials and/or similar elements in different figures are indicated with the same reference numerals.

[DE TAILED DESCRIPTION OF THE INVENTION ]

The drive circuit 100 according to the present invention is shown in Figure 1 and in Figure 2.

The drive circuit 100 comprises first an input stage 110 for generating a main signal MS representative of a movement of an actuation/selection element 120 of a household appliance 1.

The actuation/selection element 120 is movable in different directions Dl, D2, preferably in two opposite directions.

As will become apparent hereafter, the actuation/selection element 120 may be a knob 27 of an oven 21, rotatable with respect to a frame 22 of the same oven both clockwise (arrow Dl, in fig. 4), and counter-clockwise (arrow D2 in fig. 4) .

By means of the actuation/selection element, a user can set one or more operating parameters of the household appliance 1, such as, in the case of the oven 21, a cooking time and/or a baking temperature and/or a cooking program.

In particular, every operating position of the actuation/selection element 120, which for instance can correspond to a respective angular position, is associated with a corresponding program or parameter value for operating the household appliance 1. Preferably said actuation/selection element 120 is associated with an electric circuit EC adapted to generate a corresponding electric signal ES, representing said operating position, as a function of the operating position of the actuation/selection element 120.

In practice, said electric circuit EC may be realised as a potentiometer, adapted to generate an electrical signal ES of different level, in particular of different voltage level, as a function of the position of said actuation/selection element 120.

In a preferred embodiment, said electric circuit EC generates, every time a change is made to said activation/selection element 120, a voltage step, the sign of which depends on the direction in which the activation/selection element 120 has been moved.

The input stage 110 is preferably a differentiator stage, in particular being configured for converting said voltage step into a corresponding voltage pulse.

Said voltage pulse will have a sign corresponding to the sign of the voltage step outputted from said electric circuit EC.

The drive circuit 100 also comprises a first comparator stage 130 connected downstream of said input stage 110.

The first comparator stage 130 is configured for detecting said main signal MS when the latter has a given sign.

By way of example, the circuit diagram shown in figure 1 provides for said first comparator stage 130 to detect said main signal MS when the latter has a positive sign.

Once the main signal MS is detected, said first comparator stage 130 generates a first control signal CS1 which, as will become apparent hereafter, wakes-up said household appliance 1.

Preferably, the first comparator stage 130 may include a first comparator 131, preferably comprising an operational amplifier and having a first input 132 for receiving said main signal MS and a second input 133 for receiving a first reference Refl.

The first comparator 131 is preferably configured for generating said first control signal CS1 as a function of a comparison between main signal MS and first reference Refl.

In an advantageous embodiment, the drive circuit 100 also comprises a second comparator stage 140 connected downstream of said input stage 110.

The second comparator stage 140 is configured for detecting said main signal MS when the latter has a different sign, and in particular opposite to said given sign, i.e. the sign of the main signal MS when the latter is detected by the first comparator stage 130.

By way of example, the circuit diagram shown in figure 1 provides for said second comparator stage 140 to detect said main signal MS when the latter has a negative sign.

Once the main signal MS is detected, the second comparator stage 140 generates a second control signal CS2 which, as will become apparent hereafter, wakes-up said household appliance 1.

Preferably, the second comparator stage 140 may include a second comparator 141, preferably comprising an operational amplifier and having a first input 142 for receiving the main signal MS, and a second input 143 for receiving a second reference Ref2.

The second comparator 141 is preferably configured for generating the second control signal CS2 as a function of a comparison between said main signal MS and said second reference Ref2.

Conveniently, the first comparator 131 and the second comparator 141 have said respective control signal CS1, CS2 generated on an output port of open-collector or open-drain type, thus allowing the direct connection of the respective output ports.

In addition, the drive circuit 100 comprises, advantageously, an output stage 150 configured for generating, when it receives the first input control signal CS1 and/or the second input control signal CS2, a corresponding reactivation signal RS for driving the household appliance 1 from a stand^¬ by condition to an operating condition.

In practice, as schematically shown in figure 1, the output stage 150 may be realised as a simple connection between the outputs of the first and second comparator stage 130, 140, in order to realise a sort of logical OR and provide for the first or second output control signal CS1, CS2 depending on which of the two signals is generated by the upstream stages.

In one embodiment (figure 2), the reactivation signal RS is configured for driving a control unit 6 of household appliance 1 from a stand-by condition to an operating condition.

In practice, in this embodiment, the reactivation signal RS is sent directly on the appropriate wake-up pin of the control unit 6, i.e. of the microprocessor, of household appliance 1, so that the latter exits the stand-by conditions in which it was previously put and resumes the operating conditions.

In an alternative embodiment (figure 3), the reactivation signal RS is configured for acting upon a switch 10, preferably realised as an electronic switch circuit, forming part of household appliance 1. In particular, the reactivation signal RS is configured for driving said switch 10 from a first condition, in which it keeps household appliance 1 in a stand-by condition, to a second condition, in which it brings said household appliance 1 into an operating condition.

Said switch 10 is interposed between the 12 V power supply, that is typically provided in most of the household appliances, and the electronic control board of household appliance 1.

When the switch 10 is open (first condition), the board is powered off and the household appliance is in a stand-by mode.

Typically, the switch 10 is opened as a result of an "open" command that is sent by the control unit 6 (i.e. by the microprocessor mounted on the electronic control board) , in a manner known per se.

When, upon receiving a reactivation signal RS, the switch 10 closes (second condition), the household appliance 1 is brought back into operating conditions.

As mentioned above, the drive circuit 100 can be advantageously integrated in a household appliance 1.

The household appliance 1 comprises first one operating zone 4 which, in the case of an oven 21 (fig. 4), may consist of a cavity or muffle 24 in which the food to be cooked or heated is positioned.

The household appliance 1 also comprises one or more actuators 5, 15, of the electromechanical and/or electro^¬ thermal type, operationally active on operating zone 4.

The actuators 5, 15 are the elements by means of which said household appliance 1 performs its main functions.

By way of example, in the case of the oven 21, the actuators 5, 15 may comprise one or more heating elements 25, such as heating resistors, and a fan 215, adapted to ventilate the cavity 24 for achieving uniform heat distribution inside the same cavity.

As mentioned above, the household appliance 1 may comprises, advantageously, a control unit 6 configured for managing the operating condition of said one or more actuators 5, 15.

In the specific case of the oven 21, control unit 6 is active on heating elements 25 and fan 215 to perform the cooking/heating cycles that have been set.

The household appliance 1 also comprises an actuation/selection element 120, associated with said one or more actuators 5, 15 and/or with said control unit 6, in order to define operating conditions of said household appliance 1.

The actuation/selection element 120 is movable with respect to the frame 22 of household appliance 1.

In the case of the oven 21, the actuation/selection element 120 may be a knob 27 rotatably mounted in the frame 22 of said oven 21.

By means of the knob 27, the user can set manually temperature and/or time and/or other operating modes of the oven 21.

The invention achieves important advantages.

The invention allows first to implement a wake-up technique from the simple stand-by mode, also characterised by reduced manufacturing costs.

Furthermore, the invention allows to enhance household appliances' simplicity and speed of use without substantially increasing stand-by energy consumption.

Claims

1. A drive circuit (100) for driving a household appliance from a stand-by condition to an operating condition, said circuit comprising:

- an input stage (110) for generating a main signal (MS) representative of a movement of an actuation/selection element (120) of a household appliance (1), said main signal (MS) having a different sign depending on a direction of movement (Dl, D2 ) of said actuation/selection element (120);

- a first comparator stage (130) for detecting said main signal (MS) when the latter has a given sign and for outputting a corresponding first control signal (CS1);

- a second comparator stage (140) for detecting said main signal (MS) when the latter has a sign opposite to said given sign and for outputting a corresponding second control signal (CS2) ;

- an output stage (150) configured for generating, when it receives said first control signal (CS1) and/or said second control signal (CS2), a corresponding reactivation signal (RS) for driving said household appliance (1) from a stand-by condition to an operating condition.

2. A circuit according to claim 1, wherein said input stage (110) is a differentiator stage.

3. A circuit according to claim 2, wherein said actuation/selection element (120) can be driven among a plurality of operating positions, said actuation/selection element (120) being associated with a respective electric circuit (EC) adapted to generate a corresponding electric signal (ES) as a function of the operating position of the actuation/selection element (120), said input stage (110) being configured for converting said electric signal (ES) into said main signal (MS) .

4. A circuit according to claim 3, wherein said electric signal (ES) has a step waveform, in particular a voltage step waveform.

5. A circuit according to claim 3 or 4, wherein said main signal (MS) has a pulse waveform, preferably a voltage pulse waveform.

6. A circuit according to any one of the preceding claims, wherein said first comparator stage (130) includes a first comparator (131) preferably comprising an operational amplifier and having a first input (132) for receiving said main signal (MS) and a second input (133) for receiving a first reference (Refl), said first comparator (131) being configured for generating said first control signal (CS1) as a function of a comparison between said main signal (MS) and said first reference (Refl) .

7. A circuit according to any one of the preceding claims, wherein said second comparator stage (140) includes a second comparator (141) preferably comprising an operational amplifier and having a first input (142) for receiving said main signal (MS) and a second input (143) for receiving a second reference (Ref2), said second comparator (141) being configured for generating said second control signal (CS2) as a function of a comparison between said main signal (MS) and said second reference (Ref2) .

8. A circuit according to any one of the preceding claims, wherein said reactivation signal (RS) is configured for driving a control unit (6) of said household appliance (1) from a stand-by condition to an operating condition.

9. A circuit according to any one of claims 1 to 7, wherein said reactivation signal (RS) is configured for acting upon a switch (10) included in said household appliance (1) and driving it from a first condition, in which it keeps said household appliance (1) in a stand-by condition, to a second condition, in which it brings said household appliance (1) into an operating condition.

10. A household appliance (1) comprising:

- at least one operating zone (4);

- one or more actuators (5, 15) of the electromechanical and/or electrothermal type, operationally active on said operating zone (4);

a control unit (6) configured for controlling the operation of said one or more actuators (5, 15);

- at least one actuation/selection element (120) associated with said one or more actuators (5, 15) and/or with said control unit (6), said actuation/selection element (120) being movable in order to define operating conditions of said household appliance ( 1 ) ;

- at least one drive circuit (100) according to any one of the preceding claims.

11. A household appliance according to claim 10, wherein the reactivation signal (RS) generated by said drive circuit (100) is configured for driving said control unit (6) from a stand-by condition to an operating condition.

12. A household appliance according to claim 10, comprising a switch (10), which can be driven between a first condition, wherein it keeps said household appliance (1) in a stand-by condition, and a second condition, in which it brings said household appliance (1) into an operating condition, said reactivation signal (RS) being configured for driving said switch (10) from the first condition to the second condition.

13. A household appliance according to any one of claims 10 to 12, wherein:

- said household appliance (1) is an oven (21);

- said one or more actuators (5, 15) comprise one or more heating elements (25) and/or a fan (215) ;

- said at least one operating zone (4) comprises a cavity

(24) or muffle heated by said one or more heating elements

(25) ;

- said actuation/selection element (120) comprises at least one knob (27) associated with said control unit (6) and/or with said one or more heating elements (25) and/or with said fan (215) , and movable in order to determine operating conditions of said oven (21) .