Cookware detection circuit of cooking utensil, control method and cooking utensil

Abstract

The invention provides a cookware detection circuit of a cooking utensil, a control method and the cooking utensil. The circuit comprises a signal acquisition circuit, a comparison circuit and a controller, the signal acquisition circuit is connected with the comparison circuit, and the comparison circuit is connected with the controller; the signal acquisition circuit comprises an infrared transmitting and receiving unit, the infrared transmitting direction of the infrared transmitting and receiving unit faces the position, where a pot is placed, of the cooking utensil, and the signal acquisition circuit is used for transmitting infrared rays and outputting first voltage according to the intensity of received infrared signals; the comparison circuit is used for outputting a first level signal under the condition that the first voltage is greater than the reference voltage, and outputting a second level signal under the condition that the first voltage is smaller than the reference voltage; the controller is used for determining whether cookware is placed on the cooking utensil or not according to the signal output by the comparison circuit. According to the cookware detection circuit of the cooking utensil, the sensitivity of cookware detection is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of household appliance technology, and in particular to a pot detection circuit, a control method and a cooking appliance. Background Art

[0002] If a cooking appliance is continuously heated without a pot in it, the internal circuit of the cooking appliance will overheat and be damaged, and may also cause safety problems such as fire or burns. In the related art, a pot detection method is used to control the heating of the cooking appliance to ensure the safety of the cooking appliance.

[0003] The pot detection method in the related art usually detects whether a pot is placed by a gravity sensor configured on the cooking utensil. In this method, when a light pot is placed on the cooking utensil, the pot may not be detected, and the sensitivity of the pot detection is low. Summary of the invention

[0004] The embodiments of the present application provide a pot detection circuit, a control method and a cooking appliance for a cooking appliance to solve the problem of low sensitivity of pot detection.

[0005] In a first aspect, the present application provides a pot detection circuit for a cooking utensil, comprising: a signal acquisition circuit, a comparison circuit and a controller; the signal acquisition circuit is connected to the comparison circuit, and the comparison circuit is connected to the controller;

[0006] The signal acquisition circuit comprises an infrared transceiver unit, the infrared ray emission direction of the infrared transceiver unit is toward the position where the pot is placed on the cooking utensil, and the signal acquisition circuit is used to emit infrared rays and output a first voltage according to the intensity of the received infrared signal;

[0007] The comparison circuit is used to output a first level signal when the first voltage is greater than a reference voltage, and to output a second level signal when the first voltage is less than the reference voltage;

[0008] The controller is used for determining whether a pot is placed on the cooking utensil according to a signal output by the comparison circuit.

[0009] The pot detection circuit realizes the pot detection circuit of the cooking utensil based on the reflection of infrared rays by the pot when the pot is placed on the cooking utensil. The detection is not affected by the weight of the pot, thereby improving the sensitivity of the pot detection.

[0010] Optionally, the infrared transceiver unit includes a transmitting unit and a receiving unit, and the signal acquisition circuit further includes a filtering circuit and a first voltage divider circuit;

[0011] The transmitting unit and the receiving unit are respectively connected to a power supply through the first voltage divider circuit, the receiving unit is connected to the filter circuit, and a connection point between the receiving unit and the first voltage divider circuit is an output end of the first voltage.

[0012] Optionally, the transmitting unit includes an infrared transmitting tube D, the receiving unit includes an infrared receiving tube Q, the filtering circuit includes a first capacitor C1, and the first voltage divider circuit includes a first resistor R1 and a second resistor R2;

[0013] The first end of the first resistor R1 is connected to the first end of the infrared emitting tube D, and the second end of the first resistor R1 is connected to the power supply;

[0014] The first end of the second resistor R2 is connected to the first end of the infrared receiving tube Q and the first input end of the comparison circuit respectively, and the second end of the second resistor R2 is connected to the power supply;

[0015] The first end of the infrared receiving tube Q is connected to the first end of the first capacitor C1;

[0016] The second end of the infrared receiving tube Q, the second end of the infrared transmitting tube D, and the second end of the first capacitor C1 are connected to the ground point respectively.

[0017] Optionally, the comparison circuit includes a comparator U, a second voltage divider circuit and a feedback circuit;

[0018] The first input terminal of the comparator U is connected to the connection point between the receiving unit and the first voltage-dividing circuit, the second input terminal of the comparator U is connected to the second voltage-dividing circuit, the second voltage-dividing circuit is connected between the power supply and the ground point, one end of the feedback circuit is connected to the first voltage-dividing circuit, the second end of the feedback circuit is connected to the output terminal of the comparator U, and the voltage of the second input terminal of the comparator U is the reference voltage.

[0019] Optionally, the second voltage-dividing circuit includes a sliding resistor R3, and the feedback circuit includes a fourth resistor R4;

[0020] The sliding resistor R3 is connected between the power supply and the ground point, and the second input end of the comparator U is connected to the sliding contact of the sliding resistor R3.

[0021] Optionally, the cookware detection circuit further includes a voltage stabilizing circuit, and the voltage stabilizing circuit is connected to the signal acquisition circuit.

[0022] Optionally, the voltage stabilizing circuit includes: a fifth resistor R5 and a second capacitor C2;

[0023] A first end of the fifth resistor R5 is connected to the signal acquisition circuit, and a second end of the fifth resistor R5 is connected to the ground point;

[0024] A first end of the second capacitor C2 is connected to a first end of the fifth resistor R5 , and a second end of the second capacitor C2 is connected to the ground point.

[0025] The voltage stabilizing circuit can stabilize the voltage of the pot detection circuit of the cooking appliance, so that each component in the circuit can work under a stable voltage.

[0026] In a second aspect, the present application provides a control method for a cooking appliance, wherein the cooking appliance comprises a pot detection circuit of the cooking appliance as described in any one of the first aspects, and the method comprises:

[0027] When the cooking appliance is in a standby state, if it is determined that a pot is placed on the cooking appliance, setting the heating function of the cooking appliance to an available state;

[0028] In response to the heating instruction, the cooking appliance is controlled to heat.

[0029] Optionally, the cooking appliance control method further includes:

[0030] When the cooking appliance is in a heating state, if it is determined that no pot is placed on the cooking appliance, the cooking appliance is controlled to stop heating, and the heating function of the cooking appliance is set to an unavailable state.

[0031] The control method of the cooking appliance controls the cooking appliance to stop heating and sets the heating function of the cooking appliance to an unavailable state when detecting that no pot is placed on the cooking appliance. This prevents the cooking appliance from continuously heating when no pot is placed on the cooking appliance, reduces equipment loss and avoids accidents.

[0032] In a third aspect, the present application provides a cooking utensil, comprising: a pot detection circuit of the cooking utensil as described in any one of the first aspects.

[0033] The cooking utensil can detect whether a pot is placed on the cooking utensil, and when it is detected that a pot is placed on the cooking utensil, the heating function of the cooking utensil is set to an available state. When it is detected that no pot is placed on the cooking utensil, the heating function of the cooking utensil is set to an unavailable state, thereby improving the safety of the cooking utensil.

[0034] The pot detection circuit, control method and cooking utensil of the present embodiment include a signal acquisition circuit, a comparison circuit and a controller; the signal acquisition circuit is connected to the comparison circuit, and the comparison circuit is connected to the controller; the signal acquisition circuit includes an infrared transceiver unit, the infrared ray emission direction of the infrared transceiver unit is toward the position where the pot is placed on the cooking utensil, the signal acquisition circuit is used to emit infrared rays, and output a first voltage according to the intensity of the received infrared signal; the comparison circuit is used to output a first level signal when the first voltage is greater than a reference voltage, and output a second level signal when the first voltage is less than the reference voltage; the controller is used to determine whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit. The present application realizes the pot detection circuit of the cooking utensil based on the reflection of infrared rays by the pot when the pot is placed on the cooking utensil, and the detection is not affected by the weight of the pot, thereby improving the sensitivity of the pot detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0036] Figure 1 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 1 ;

[0037] Figure 2 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 2 ;

[0038] Figure 3 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 3 ;

[0039] Figure 4 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 4 ;

[0040] Figure 5 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 5 ;

[0041] Figure 6 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 6 ;

[0042] Figure 7 A schematic diagram of the control method of the cooking appliance provided in this application Figure 1 ;

[0043] Figure 8 A schematic diagram of the control method of the cooking appliance provided in this application Figure 2 ;

[0044] Fig. 9 A schematic diagram of the structure of a cooking utensil provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0046] Continuously heating a cooking appliance without a pot inside will cause the internal circuit of the cooking appliance to overheat and burn, which will not only cause irreversible damage to the cooking appliance, but may also cause safety issues such as fire or burns.

[0047] In the related art, a gravity sensor is usually arranged on the cooking utensil to detect whether a pot is placed on the cooking utensil. When it is detected that a pot is placed on the cooking utensil, the heating of the cooking utensil is controlled. When it is detected that no pot is placed on the cooking utensil, the heating of the cooking utensil is stopped and prohibited.

[0048] In this manner, if other objects are placed on the cooking utensil by mistake, or if artificial force is applied to cause the gravity sensor to detect weight, it may be erroneously detected that there is a pot on the cooking utensil.

[0049] In order to solve the above problems, the present application proposes a pot detection circuit for a cooking utensil, comprising a signal acquisition circuit, a comparison circuit and a controller. The signal acquisition circuit emits infrared rays toward the position where the pot is placed on the cooking utensil, and outputs a first voltage according to the intensity of the received infrared signal after being reflected by the pot. The comparison circuit outputs a first level signal when the first voltage is greater than a reference voltage, and outputs a second level signal when the first voltage is less than the reference voltage. The controller determines whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit. Because the distance between the pot and the signal acquisition circuit is negatively correlated with the intensity of the received infrared signal, and further the distance between the pot and the signal acquisition circuit is positively correlated or negatively correlated with the first voltage, the distance between the pot and the signal acquisition circuit can be judged by the first voltage, that is, whether a pot is placed on the cooking utensil. The present application realizes the pot detection circuit of the cooking utensil based on the reflection of infrared rays by the pot when the pot is placed on the cooking utensil. The detection is not affected by the weight of the pot, and the sensitivity of the pot detection is improved.

[0050] The pot detection circuit of the cooking utensil proposed in the present application is described below in conjunction with specific embodiments.

[0051] Figure 1 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 1 .like Figure 1 As shown, the pot detection circuit of the cooking utensil includes a signal acquisition circuit 101 , a comparison circuit 102 and a controller 103 .

[0052] The signal acquisition circuit 101 is connected to the comparison circuit 102 , and the comparison circuit 102 is connected to the controller 103 .

[0053] The comparison circuit 102 is configured to output a first level signal when the first voltage is greater than a reference voltage, and to output a second level signal when the first voltage is less than the reference voltage.

[0054] The controller 103 is used to determine whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit 102 .

[0055] The signal acquisition circuit 101 includes an infrared transceiver unit 104, the infrared ray emission direction of the infrared transceiver unit 104 is toward the position where the pot is placed on the cooking utensil, and the signal acquisition circuit 101 is used to emit infrared rays and output a first voltage according to the received infrared signal strength. In this case, if the infrared transceiver unit 104 receives infrared rays, it indicates that the pot is within the reflection distance of the infrared transceiver unit. The reflection distance refers to the maximum distance between the object and the infrared transceiver unit 104 when the infrared rays emitted by the infrared transceiver unit 104 are reflected by the surface of the object and can be received by the infrared transceiver unit 104.

[0056] The infrared transceiver unit 104 is a device for transmitting and receiving infrared rays. The infrared transceiver unit 104 generally includes a transmitting unit and a receiving unit. The transmitting unit may be an infrared light emitting diode, and the receiving unit may be a photodiode or a phototransistor. The receiving unit may convert the received infrared rays into an electrical signal and output it. The greater the intensity of the received infrared signal, the stronger the intensity of the electrical signal output by the receiving unit.

[0057] The reference voltage is a voltage value used for comparison in the comparison circuit 102. The comparison circuit 102 can compare the first voltage and the reference voltage. If the first voltage is greater than the reference voltage, the comparison circuit 102 outputs a first level signal. If the first voltage is less than the reference voltage, the comparison circuit 102 outputs a second level signal. The first level signal and the second level signal are a set of opposite level signals. For example, the first level signal is a high level, and the second level signal is a low level.

[0058] In a possible implementation, the comparison circuit 102 can be implemented based on an operational amplifier, for example. In this implementation, for example, the end of the signal acquisition circuit 101 outputting the first voltage can be connected to the inverting input end of the operational amplifier, and the end outputting the reference voltage can be connected to the non-inverting input end. When the first voltage is greater than the reference voltage, the operational amplifier outputs a first level signal, which is a low level. When the first voltage is less than the reference voltage, the operational amplifier outputs a second level signal, which is a high level.

[0059] In a possible implementation, the comparison circuit 102 can be implemented based on a comparator, for example. In this implementation, for example, the end of the signal acquisition circuit 101 that outputs the first voltage can be connected to the first input end of the comparator, and the end that outputs the reference voltage can be connected to the second input end. When the first voltage is greater than the reference voltage, the comparator outputs a first level signal, and the first level signal is a high level. When the first voltage is less than the reference voltage, the comparator outputs a second level signal, and the second level signal is a low level.

[0060] The controller 103 is used to determine whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit 102. For example, when the signal output by the comparison circuit 102 is a first level signal, it is determined that a pot is placed on the cooking utensil. When the signal output by the comparison circuit 102 is a second level signal, it is determined that no pot is placed on the cooking utensil.

[0061] In this connection mode, the infrared transceiver unit 104 in the signal acquisition circuit 101 emits infrared rays toward the position where the pot is placed on the cooking utensil. If the pot is not placed within the reflection distance of the infrared transceiver unit 104, the infrared transceiver unit 104 cannot receive the infrared rays. If the pot is placed within the reflection distance of the infrared transceiver unit 104, but the pot is far away from the infrared transceiver unit 104, the intensity of the infrared signal received by the infrared transceiver unit 104 is weak. If the pot is placed within the reflection distance of the infrared transceiver unit 104, and the pot is close to the infrared transceiver unit 104, the intensity of the infrared signal received by the infrared transceiver unit 104 is strong. The signal acquisition circuit 101 outputs a first voltage according to the intensity of the received infrared signal. The first voltage is affected by the intensity of the received infrared signal and is positively correlated or negatively correlated with the intensity of the received infrared signal. Further, the distance between the pot and the infrared transceiver unit 104 is positively correlated or negatively correlated with the first voltage.

[0062] When the pot is not placed on the cooking utensil, it includes the case where the pot is not placed within the reflection distance of the infrared transceiver unit 104, or the pot is placed within the reflection distance of the infrared transceiver unit 104 but not placed on the cooking utensil, that is, the pot is far away from the infrared transceiver unit 104. In this case, the infrared transceiver unit 104 of the signal acquisition circuit 101 does not receive infrared rays, or the received infrared rays are weak.

[0063] When the pot is placed on the cooking utensil, that is, the pot is close to the infrared transceiver unit 104. The closer the distance between the pot and the infrared transceiver unit 104 is, the stronger the infrared rays received by the transceiver unit 104 are. In this case, the infrared transceiver unit 104 of the signal acquisition circuit 101 receives stronger infrared rays.

[0064] In a possible implementation, the reference voltage is set to a voltage that satisfies the condition that when the pot is not placed on the cooking utensil, the reference voltage is less than the first voltage, and when the pot is placed on the cooking utensil, the reference voltage is greater than the first voltage.

[0065] When the pot is not placed on the cooking utensil, the infrared transceiver unit 104 does not receive infrared rays, or the received infrared rays are weak, the first voltage output by the signal acquisition unit 101 is larger, the first voltage is greater than the reference voltage, and the comparison circuit 102 outputs a first level signal.

[0066] When the pot is placed on the cooking utensil, the infrared rays received by the infrared transceiver unit 104 are relatively strong, the first voltage output by the signal acquisition unit 101 is relatively small, the first voltage is smaller than the reference voltage, and the comparison circuit 102 outputs a second level signal.

[0067] In this implementation, the controller 103 determines that no pot is placed on the cooking utensil according to the first level signal output by the comparison circuit 102 , and determines that a pot is placed on the cooking utensil according to the second level signal output by the comparison circuit 102 .

[0068] In a possible implementation, the reference voltage is set to a voltage that satisfies the condition that when the pot is not placed on the cooking utensil, the reference voltage is greater than the first voltage, and when the pot is placed on the cooking utensil, the reference voltage is less than the first voltage.

[0069] When the pot is not placed on the cooking utensil, the infrared transceiver unit 104 does not receive infrared rays, or the received infrared rays are weak, the first voltage output by the signal acquisition unit 101 is small, the first voltage is less than the reference voltage, and the comparison circuit 102 outputs a second level signal.

[0070] When the pot is placed on the cooking utensil, the infrared rays received by the infrared transceiver unit 104 are relatively strong, the first voltage output by the signal acquisition unit 101 is relatively large, the first voltage is greater than the reference voltage, and the comparison circuit 102 outputs a first level signal.

[0071] In this implementation, the controller 103 determines that a pot is placed on the cooking utensil according to the first level signal output by the comparison circuit 102 , and determines that a pot is not placed on the cooking utensil according to the second level signal output by the comparison circuit 102 .

[0072] The pot detection circuit of the cooking utensil provided in this embodiment includes a signal acquisition circuit 101, a comparison circuit 102 and a controller 103; the signal acquisition circuit 101 is connected to the comparison circuit 102, and the comparison circuit 102 is connected to the controller 103; the signal acquisition circuit 101 includes an infrared transceiver unit 104, the infrared ray emission direction of the infrared transceiver unit 104 is toward the position where the pot is placed on the cooking utensil, the signal acquisition circuit 101 is used to emit infrared rays, and output a first voltage according to the intensity of the received infrared signal; the comparison circuit 102 is used to output a first level signal when the first voltage is greater than a reference voltage, and output a second level signal when the first voltage is less than the reference voltage; the controller 103 is used to determine whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit 102. The present application realizes the pot detection circuit of the cooking utensil based on the reflection of infrared rays by the pot when the pot is placed on the cooking utensil, and the detection is not affected by the weight of the pot, thereby improving the sensitivity of the pot detection.

[0073] In the pot detection circuit of the cooking utensil provided in this embodiment, the infrared transceiver unit 104 includes a transmitting unit and a receiving unit, and the signal acquisition circuit 101 also includes a filtering circuit and a first voltage divider circuit.

[0074] Figure 2 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 2 .

[0075] like Figure 2 As shown, the transmitting unit 201 and the receiving unit 202 are respectively connected to the power supply through the first voltage divider circuit 204, the receiving unit 202 is connected to the filter circuit 203, and the connection point between the receiving unit 202 and the first voltage divider circuit 204 is the output end of the first voltage.

[0076] The transmitting unit 201 is used to transmit infrared rays toward the position where the pot is placed on the cooking utensil, and the receiving unit 202 is used to receive infrared rays and convert infrared rays into electrical signals. The circuit composed of the filter circuit 203 and the first voltage divider circuit 204 is used to filter and divide the electrical signal of the receiving unit 202 and stabilize the output first voltage.

[0077] The filter circuit 203 may be implemented based on a capacitor, for example, to smooth the high-frequency noise generated during the process of the receiving unit 202 converting the electrical signal through the capacitor.

[0078] In the pot detection circuit of the cooking utensil provided in this embodiment, the comparison circuit 102 may include a comparator U, a second voltage divider circuit and a feedback circuit.

[0079] Figure 3 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 3 .

[0080] like Figure 3 As shown, the first input terminal of the comparator U is connected to the connection point between the receiving unit 202 and the first voltage divider circuit 204, the second input terminal of the comparator U is connected to the second voltage divider circuit 301, the second voltage divider circuit 301 is connected between the power supply and the ground point, one end of the feedback circuit 302 is connected to the first voltage divider circuit 204, the second end of the feedback circuit 302 is connected to the output terminal of the comparator U, and the voltage of the second input terminal of the comparator U is the reference voltage.

[0081] In this implementation, when the first voltage is greater than the reference voltage, the comparator U outputs a first level signal. When the first voltage is less than the reference voltage, the comparator U outputs a second level signal.

[0082] Optionally, the pot detection circuit of the cooking utensil provided in this embodiment may further include a voltage stabilizing circuit. Figure 4 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 4 .like Figure 4 As shown, the voltage stabilizing circuit 401 is connected to the signal acquisition circuit 101 .

[0083] The voltage stabilizing circuit 401 is used to stabilize the voltage of the pot detection circuit of the cooking appliance so that each component in the circuit can work under a stable voltage.

[0084] In one possible implementation, the voltage stabilizing circuit 401 may be a circuit consisting of a capacitor and a resistor in parallel connected in series in the circuit. The resistor limits the current passing through the circuit, thereby reducing the high-frequency noise in the power supply voltage. The capacitor can provide current when the power supply voltage drops, thereby smoothing the output voltage.

[0085] The following is a specific example of the pot detection circuit of the cooking utensil of the embodiment of the present application. Take the pot detection circuit of the cooking utensil including the signal acquisition circuit 101, the comparison circuit 102, the controller 103 and the voltage stabilization circuit 401, the signal acquisition circuit 101 including the transmitting unit 201, the receiving unit 202, the filter circuit 203 and the first voltage divider circuit 204, the comparison circuit 102 including the comparator U, the second voltage divider circuit 301 and the feedback circuit 302 as an example. Figure 5 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 5 .

[0086] like Figure 5 As shown, the transmitting unit 201 includes an infrared transmitting tube D, the receiving unit 202 includes an infrared receiving tube Q, the filtering circuit 203 includes a first capacitor C1, and the first voltage divider circuit 204 includes a first resistor R1 and a second resistor R2.

[0087] A first end of the first resistor R1 is connected to a first end of the infrared emitting tube D, and a second end of the first resistor R1 is connected to a power source.

[0088] A first end of the second resistor R2 is connected to a first end of the infrared receiving tube Q and a first input end of the comparison circuit 102 respectively, and a second end of the second resistor R2 is connected to a power source.

[0089] The first end of the infrared receiving tube Q is connected to the first end of the first capacitor C1.

[0090] The second end of the infrared receiving tube Q, the second end of the infrared emitting tube D, and the second end of the first capacitor C1 are connected to the ground point respectively.

[0091] In this connection mode, when the cooker is not placed on the cooking utensil, the cooker is not placed within the reflection distance of the infrared transceiver unit 104 composed of the infrared transmitting tube D and the infrared receiving tube Q, or the cooker is placed within the reflection distance of the infrared transceiver unit 104 composed of the infrared transmitting tube D and the infrared receiving tube Q, but is not placed on the cooking utensil, that is, the cooker is far away from the infrared transceiver unit 104 composed of the infrared transmitting tube D and the infrared receiving tube Q.

[0092] In this situation, the infrared emitting tube D emits infrared rays, and the infrared receiving tube Q does not receive infrared rays, or the infrared rays received by the infrared receiving tube Q are weak. The infrared signal is converted into a weaker light signal by the infrared receiving tube Q, and is filtered by the first capacitor C1 to output a smaller stable current. Due to the voltage divider effect of the second resistor R2, the connection point between the first end of the second resistor R2 and the first end of the infrared receiving tube Q outputs a larger first voltage to the first input end of the comparison circuit 102.

[0093] In this connection mode, when the pot is placed on the cooking utensil, that is, the pot is relatively close to the infrared transceiver unit 104 composed of the infrared transmitting tube D and the infrared receiving tube Q.

[0094] In this state, the infrared emitting tube D emits infrared rays, and the infrared rays received by the infrared receiving tube Q are relatively strong. The infrared signal is converted into a relatively strong light signal by the infrared receiving tube Q, and is filtered by the first capacitor C1 to output a relatively large stable current. Due to the voltage dividing effect of the second resistor R2, the connection point between the first end of the second resistor R2 and the first end of the infrared receiving tube Q outputs a relatively small first voltage to the first input end of the comparison circuit 102.

[0095] The comparison circuit 102 includes a comparator U, a second voltage divider circuit 301 and a feedback circuit 302 .

[0096] A first input terminal of the comparator U is connected to a connection point between the receiving unit 202 and the first voltage divider circuit 204, a second input terminal of the comparator U is connected to a second voltage divider circuit 301, the second voltage divider circuit 301 is connected between a power supply and a ground point, one end of the feedback circuit 302 is connected to the first voltage divider circuit 204, a second end of the feedback circuit 302 is connected to an output terminal of the comparator U, and a voltage at the second input terminal of the comparator U is a reference voltage.

[0097] The second voltage divider circuit 301 includes a sliding resistor R3, and the feedback circuit 302 includes a fourth resistor R4. The sliding resistor R3 is connected between a power supply and a ground point, and the second input terminal of the comparator U is connected to a sliding contact of the sliding resistor R3.

[0098] The sliding resistor R3 can provide an adjustable voltage divider to adjust the reference voltage of the comparator U. Figure 5 Taking the connection method in as an example, the sliding rheostat R3 can be adjusted so that when the pot is placed on the cooking utensil, the first voltage is less than the reference voltage, and when the pot is not placed on the cooking utensil, the first voltage is greater than the reference voltage.

[0099] The fourth resistor R4 feeds back a portion of the output voltage of the comparator U to the input terminal, thereby changing the voltage at the input terminal of the comparator U, so that the comparator U has different switching thresholds under different input conditions.

[0100] In this connection mode, when the pot is not placed on the cooking utensil, the connection point between the first end of the second resistor R2 and the first end of the infrared receiving tube Q outputs a larger first voltage to the first input end of the comparator U. The comparator U compares the first voltage to be greater than the reference voltage, and the output end of the comparator U outputs a first level signal, which is a high level.

[0101] Under this connection mode, when the pot is placed on the cooking utensil, the connection point between the first end of the second resistor R2 and the first end of the infrared receiving tube Q outputs a smaller first voltage to the first input end of the comparator U. The comparator U compares the first voltage to be smaller than the reference voltage, and the output end of the comparator U outputs a second level signal, which is a low level.

[0102] The voltage stabilizing circuit 401 includes a fifth resistor R5 and a second capacitor C2.

[0103] A first end of the fifth resistor R5 is connected to the signal acquisition circuit 101 , and a second end of the fifth resistor R5 is connected to the ground point.

[0104] A first end of the second capacitor C2 is connected to a first end of the fifth resistor R5 , and a second end of the second capacitor C2 is connected to the ground point.

[0105] In this connection mode, the fifth resistor R5 limits the current passing through the circuit, thereby reducing high-frequency noise in the power supply voltage, and the second capacitor C2 can provide current when the power supply voltage drops, thereby smoothing the output voltage.

[0106] based on Figure 5 In the pot detection circuit of the cooking utensil shown in the figure, when the pot is not placed on the cooking utensil, the infrared emitting tube D emits infrared rays, the infrared receiving tube Q does not receive the infrared rays, or the infrared rays received by the infrared receiving tube Q are weak, and the connection point between the first end of the second resistor R2 and the first end of the infrared receiving tube Q outputs a larger first voltage to the first input end of the comparison circuit 102, the first voltage is greater than the reference voltage, and the output end of the comparator U outputs a high level, that is, a first level signal.

[0107] When the pot is placed on the cooking utensil, the infrared emitting tube D emits infrared rays, and the infrared receiving tube Q receives stronger infrared rays. The connection point between the first end of the second resistor R2 and the first end of the infrared receiving tube Q outputs a smaller first voltage to the first input end of the comparison circuit 102. The first voltage is less than the reference voltage, and the output end of the comparator U outputs a low level, that is, a second level signal.

[0108] The controller 103 determines that no pot is placed on the cooking utensil according to the first level signal output by the comparator U, and determines that a pot is placed on the cooking utensil according to the second level signal output by the comparator U.

[0109] Above Figure 5 The second voltage divider circuit 301 in the pot detection circuit of the cooking utensil shown includes a sliding rheostat R3, which can be used to adjust the reference voltage of the comparator U. Optionally, when the reference voltage is determined, the second voltage divider circuit 301 can also be implemented based on a fixed resistor. The determined reference voltage can satisfy the condition that the first voltage is less than the reference voltage when the pot is placed on the cooking utensil, and the first voltage is greater than the reference voltage when the pot is not placed on the cooking utensil.

[0110] Figure 6 A schematic diagram of the structure of the pot detection circuit of the cooking utensil provided in this application Figure 6 .

[0111] like Figure 6 As shown, in this implementation, the second voltage divider circuit 301 includes a sixth resistor R6 and a seventh resistor R7.

[0112] The first end of the sixth resistor R6 is connected to the power supply, the first end of the seventh resistor R7 is connected to the ground point, the second end of the sixth resistor R6 is connected to the second end of the seventh resistor R7, and the connection point between the second end of the sixth resistor R6 and the second end of the seventh resistor R7 is connected to the second input terminal of the comparator U. Through the voltage division of the sixth resistor R6 and the seventh resistor R7, the second voltage divider circuit 301 provides a reference voltage to the second input terminal of the comparator U.

[0113] The pot detection circuit of the cooking utensil provided in this embodiment includes a signal acquisition circuit 101, a comparison circuit 102, a controller 103 and a voltage stabilizing circuit 401. The signal acquisition circuit 101 is connected to the comparison circuit 102, and the comparison circuit 102 is connected to the controller 103; the signal acquisition circuit 101 includes an infrared transceiver unit 104, the infrared ray emission direction of the infrared transceiver unit 104 is toward the position where the pot is placed on the cooking utensil, and the signal acquisition circuit 101 is used to emit infrared rays and output a first voltage according to the intensity of the received infrared signal; the comparison circuit 102 is used to output a first level signal when the first voltage is greater than a reference voltage, and to output a second level signal when the first voltage is less than the reference voltage; the controller 103 is used to determine whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit 102. The present application realizes the pot detection circuit of the cooking utensil based on the reflection of infrared rays by the pot when the pot is placed on the cooking utensil, and the detection is not affected by the weight of the pot, thereby improving the sensitivity of the pot detection.

[0114] The present application also provides a cooking appliance control method, wherein the cooking appliance includes the pot detection circuit of the cooking appliance provided in this embodiment. The cooking appliance control method can be used for any cooking appliance controller or cooking appliance, and the following description is made by taking the cooking appliance controller 103 as an example. The cooking appliance controller 103 can receive the first level signal or the second level signal of the pot detection circuit of the cooking appliance, and can also control the heating of the cooking appliance.

[0115] When the cooking appliance is in a standby state, if it is determined that a pot is placed on the cooking appliance, the heating function of the cooking appliance is set to an available state. The standby state is a state where the cooking appliance is powered on and not heated. If the heating function of the cooking appliance is set to an available state, the cooking appliance can be controlled to heat after receiving a heating instruction. Conversely, if the heating function of the cooking appliance is set to an unavailable state, the heating instruction will not be triggered in this state, that is, the cooking appliance will not heat.

[0116] In response to the heating instruction, the cooking appliance is controlled to heat. The heating instruction is an instruction to instruct the cooking appliance to heat. The heating instruction can be triggered, for example, by a display system configured on the cooking appliance, and the display system has a touch unit. In this way, the user can trigger the switch through the touch unit of the display system of the cooking appliance, or through a mechanical switch configured on the cooking appliance, etc., and this application does not limit this.

[0117] When the cooking appliance is in a heating state, if the controller 103 determines that no pot is placed on the cooking appliance, the cooking appliance is controlled to stop heating and the heating function of the cooking appliance is set to an unavailable state. The current state indicates that during the heating process of the cooking appliance, it is detected that the pot is removed, so the cooking appliance is controlled to stop heating and the heating function of the cooking appliance is set to an unavailable state.

[0118] Optionally, after the heating function of the cooking appliance is set to an unavailable state or an available state, the current state of the heating function may be prompted through the display system of the cooking appliance.

[0119] Figure 7 A schematic diagram of the control method of the cooking appliance provided in this application Figure 1 .like Figure 7 As shown, when the cooking appliance is in a standby state, the control method of the cooking appliance specifically includes:

[0120] S701: Detect that a pot is placed on the cooking utensil.

[0121] If yes, execute step S703;

[0122] If not, execute step S702.

[0123] S702: Set the heating function of the cooking appliance to an unavailable state.

[0124] S703: Set the heating function of the cooking appliance to an available state.

[0125] Figure 8 A schematic diagram of the control method of the cooking appliance provided in this application Figure 2 .like Figure 8 As shown, when the cooking appliance is in a heating state, the control method of the cooking appliance specifically includes:

[0126] S801: Detect that a pot is placed on the cooking utensil.

[0127] If yes, execute step S804;

[0128] If not, execute step S802.

[0129] S802: Control the cooking appliance to stop heating.

[0130] S803: Set the heating function of the cooking appliance to an unavailable state.

[0131] S804: Control the cooking appliance to continue heating.

[0132] The control method of the cooking appliance proposed in the present application controls the cooking appliance to stop heating and sets the heating function of the cooking appliance to an unavailable state when it is detected that no pot is placed on the cooking appliance. The control method of the present application prevents the cooking appliance from continuously heating when no pot is placed on it, reduces equipment loss and avoids accidents.

[0133] The present application provides a cooking appliance, including a pot detection circuit of the cooking appliance provided in the present application.

[0134] Fig. 9 A schematic diagram of the structure of a cooking utensil provided in an embodiment of the present application.

[0135] The infrared transceiver unit 104 may be installed at a location other than the heating area 902 on the panel 901 of the cooking appliance.

[0136] Optionally, the infrared transceiver unit 104 is farther away from the edge of the heating area 902 than a first distance threshold and less than a second distance threshold. The first distance threshold may be set to 2 centimeters, for example, and the second distance threshold may be set to 25 centimeters, for example.

[0137] Optionally, the infrared transceiver unit 104 protrudes from the panel 901, and the height of the infrared transceiver unit 104 protruding from the panel is less than a height threshold. The height threshold can be set according to the height of the cookware, and the height threshold is less than the height of the cookware.

[0138] Optionally, the angle between the infrared transceiver unit 104 and the panel is smaller than the angle threshold, so that the infrared rays emitted by the infrared transceiver unit 104 can be reflected by the surface of the cookware and received by the infrared transceiver unit 104. The angle threshold can be set to 30 degrees, for example.

[0139] It should be understood that the infrared transceiver unit 104 can be a unit integrating the transmitting unit 201 and the receiving unit 202. Optionally, the transmitting unit 201 and the receiving unit 202 of the infrared transceiver unit 104 can also be installed separately. The positions of the transmitting unit 201 and the receiving unit 202 enable the infrared rays emitted by the transmitting unit 201 to be reflected by the surface of the cookware and received by the receiving unit 202.

[0140] The cooking utensil proposed in the present application can detect whether a pot is placed on the cooking utensil. When it is detected that a pot is placed on the cooking utensil, the heating function of the cooking utensil is set to an available state. When it is detected that no pot is placed on the cooking utensil, the heating function of the cooking utensil is set to an unavailable state. The cooking utensil of the present application improves the safety of the cooking utensil in use.

[0141] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules is only a logical function division, and there may be other division methods in actual implementation, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0142] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0143] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present application, rather than to limit them. Although the embodiments of the present application have been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the embodiments of the present application.

Claims

1. A pot detection circuit for a cooking utensil, characterized in that: include: A signal acquisition circuit (101), a comparison circuit (102) and a controller (103); the signal acquisition circuit (101) is connected to the comparison circuit (102), and the comparison circuit (102) is connected to the controller (103); The signal acquisition circuit (101) comprises an infrared transceiver unit (104), the infrared ray emission direction of the infrared transceiver unit (104) is oriented toward the position on the cooking utensil where the pot is placed, and the signal acquisition circuit (101) is used to emit infrared rays and output a first voltage according to the intensity of the received infrared signal; The comparison circuit (102) is used for outputting a first level signal when the first voltage is greater than a reference voltage, and for outputting a second level signal when the first voltage is less than the reference voltage; The controller (103) is used to determine whether a pot is placed on the cooking utensil according to the signal output by the comparison circuit (102).

2. The cookware detection circuit according to claim 1, characterized in that: The infrared transceiver unit (104) comprises a transmitting unit (201) and a receiving unit (202); the signal acquisition circuit (101) further comprises a filter circuit (203) and a first voltage divider circuit (204); The transmitting unit (201) and the receiving unit (202) are respectively connected to a power supply via the first voltage divider circuit (204); the receiving unit (202) is connected to the filter circuit (203); and the connection point between the receiving unit (202) and the first voltage divider circuit (204) is the output end of the first voltage.

3. The pot detection circuit according to claim 2, characterized in that: The transmitting unit (201) comprises an infrared transmitting tube D, the receiving unit (202) comprises an infrared receiving tube Q, the filtering circuit (203) comprises a first capacitor C1, and the first voltage dividing circuit (204) comprises a first resistor R1 and a second resistor R2; The first end of the first resistor R1 is connected to the first end of the infrared emitting tube D, and the second end of the first resistor R1 is connected to the power supply; The first end of the second resistor R2 is connected to the first end of the infrared receiving tube Q and the first input end of the comparison circuit (102) respectively, and the second end of the second resistor R2 is connected to the power supply; The first end of the infrared receiving tube Q is connected to the first end of the first capacitor C1; The second end of the infrared receiving tube Q, the second end of the infrared transmitting tube D, and the second end of the first capacitor C1 are connected to the ground point respectively.

4. The cookware detection circuit according to claim 2, characterized in that: The comparison circuit (102) comprises a comparator U, a second voltage divider circuit (301) and a feedback circuit (302); The first input end of the comparator U is connected to the connection point between the receiving unit (202) and the first voltage divider circuit (204), the second input end of the comparator U is connected to the second voltage divider circuit (301), the second voltage divider circuit (301) is connected between the power supply and the ground point, one end of the feedback circuit (302) is connected to the first voltage divider circuit (204), the second end of the feedback circuit (302) is connected to the output end of the comparator U, and the voltage of the second input end of the comparator U is the reference voltage.

5. The cookware detection circuit according to claim 4, characterized in that: The second voltage dividing circuit (301) comprises a sliding resistor R3, and the feedback circuit (302) comprises a fourth resistor R4; The sliding resistor R3 is connected between the power supply and the ground point, and the second input end of the comparator U is connected to the sliding contact of the sliding resistor R3.

6. The cookware detection circuit according to any one of claims 1 to 5, characterized in that: It also includes a voltage stabilizing circuit (401), and the voltage stabilizing circuit (401) is connected to the signal acquisition circuit (101).

7. The cookware detection circuit according to claim 6, characterized in that: The voltage stabilizing circuit (401) comprises: a fifth resistor R5 and a second capacitor C2; A first end of the fifth resistor R5 is connected to the signal acquisition circuit (101), and a second end of the fifth resistor R5 is connected to a ground point; A first end of the second capacitor C2 is connected to a first end of the fifth resistor R5 , and a second end of the second capacitor C2 is connected to the ground point.

8. A method for controlling a cooking appliance, characterized in that: The cooking utensil comprises the pot detection circuit according to any one of claims 1 to 7, and the method comprises: When the cooking appliance is in a standby state, if it is determined that a pot is placed on the cooking appliance, setting the heating function of the cooking appliance to an available state; In response to the heating instruction, the cooking appliance is controlled to heat.

9. The method according to claim 8, characterized in that Also includes: When the cooking appliance is in a heating state, if it is determined that no pot is placed on the cooking appliance, the cooking appliance is controlled to stop heating, and the heating function of the cooking appliance is set to an unavailable state.

10. A cooking utensil, characterized in that: include: A cookware detection circuit as claimed in any one of claims 1 to 7.

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