CN113932938B

CN113932938B - Detection circuit, control method, cooking appliance, and computer-readable storage medium

Info

Publication number: CN113932938B
Application number: CN202010604473.8A
Authority: CN
Inventors: 凌晓春; 陈立鹏; 朱洁乐
Original assignee: Midea Group Co Ltd; Guangdong Midea Kitchen Appliances Manufacturing Co Ltd
Current assignee: Midea Group Co Ltd; Guangdong Midea Kitchen Appliances Manufacturing Co Ltd
Priority date: 2020-06-29
Filing date: 2020-06-29
Publication date: 2024-05-24
Anticipated expiration: 2040-06-29
Also published as: CN113932938A

Abstract

The invention provides a detection circuit, a control method, a cooking appliance and a computer readable storage medium. Wherein the detection circuit includes a variable resistive component configured to change a resistance value in accordance with a change in an environmental parameter; the output end of the signal output circuit is connected with the variable resistance component; the sampling end of the sampling circuit is connected with the variable resistance component; a control device connected to the signal output circuit and the sampling circuit, the control device configured to output a test signal to the variable resistive element through the signal output circuit; acquiring a voltage value of the variable resistance component through a sampling circuit; the resistance value of the variable resistive component is determined based on the test signal and the voltage value. The resistance value of the variable resistance component can be determined without setting other chips, and the whole production cost of the detection circuit is reduced.

Description

Detection circuit, control method, cooking appliance, and computer-readable storage medium

Technical Field

The invention belongs to the technical field of kitchen appliances, and particularly relates to a detection circuit, a control method of the detection circuit, a cooking appliance and a computer readable storage medium.

Background

Ovens are typically equipped with a three-point probe as a temperature sensing device. To save the number of connection pins of the external connector, three thermistors inside the three-point temperature probe are generally connected in a triangle shape. Designing a detection circuit capable of rapidly reading the resistance value of a thermistor is a problem to be solved.

Disclosure of Invention

The present invention aims to solve one of the technical problems existing in the prior art or related technologies.

To this end, a first aspect of the invention proposes a detection circuit.

A second aspect of the present invention proposes a control method of a detection circuit.

A third aspect of the present invention provides a cooking appliance.

A fourth aspect of the present invention proposes a computer-readable storage medium.

In view of this, a detection circuit is proposed according to a first aspect of the invention, comprising: a variable resistive component configured to change a resistance value according to a change in an environmental parameter; the output end of the signal output circuit is connected with the variable resistance component; the sampling end of the sampling circuit is connected with the variable resistance component; a control device connected to the signal output circuit and the sampling circuit, the control device configured to output a test signal to the variable resistive element through the signal output circuit; acquiring a voltage value of the variable resistance component through a sampling circuit; the resistance value of the variable resistive component is determined based on the test signal and the voltage value.

The detection circuit provided by the invention comprises a variable resistance component, a signal output circuit, a sampling circuit and a control device. The variable resistance component comprises at least one variable resistance element, the output end of the signal output end circuit and the sampling end of the sampling circuit are connected with the variable resistance component, the signal output circuit can send a test signal to the variable resistance component, the sampling signal acquires the voltage value of the variable resistance component through the sampling end connected with the variable resistance component, and the resistance value of the variable resistance component can be determined according to the sent test signal and the acquired voltage value. And a test signal is sent through the signal output end, the voltage value of the corresponding position is collected through the sampling circuit, and the resistance value of the variable resistance element can be determined according to the voltage value and the test signal. Compared with the scheme for detecting the resistance of the variable resistance component in the prior art, the resistance value of the variable resistance component can be determined without setting other chips, and the overall production cost of the detection circuit is reduced.

Only one resistive element is arranged in the variable resistive component, and the test signal comprises a current signal, so that the resistance value of the resistive element can be directly determined directly through the current signal and the acquired voltage value.

The variable resistive component is provided with a plurality of resistive elements, the test signal comprises a current signal, and the total resistance value of the plurality of connected resistive elements can be directly determined through the test signal and the acquired voltage value.

The resistance value of the variable resistance component is changed according to the change of the environmental parameter, so that the environmental parameter can be detected by using the detection circuit. In particular, the variable resistive component is disposed at a location where an environmental parameter is desired to be sensed. For example, when the temperature of the food to be cooked in the cooking appliance needs to be detected, the variable resistance component is arranged at the sampling end of the temperature probe, the temperature probe stretches into the food to be detected, the resistance value of the variable resistance component correspondingly changes according to the temperature of the food, and the corresponding relation between the resistance value of the variable resistance component and the temperature parameter is obtained according to calculation, so that the detected temperature of the food to be cooked is determined. The method realizes the rapid detection of the environmental parameters through the detection circuit.

In addition, the detection circuit in the technical scheme provided by the invention can also have the following additional technical characteristics:

In one possible design, the variable resistive component comprises: a first resistive element; a second resistive element having a first end connected to the first end of the first resistive element; and the first end of the third resistive element is connected with the second end of the first resistive element, the second end of the third resistive element is connected with the second end of the second resistive element, and the second end of the third resistive element is connected with the grounding end.

In the design, the variable resistive component comprises a first resistive element, a second resistive element and a third resistive element which are sequentially connected in an ending mode, namely the first resistive element, the second resistive element and the third resistive element are connected together in a triangular connection mode, and through the arrangement of the three resistive elements in the variable resistive component, the environment parameters which can be detected simultaneously are achieved, the range of the detection circuit for collecting the environment parameters is improved, and the accuracy for collecting the environment parameters is improved.

The first resistive element, the second resistive element and the third resistive element can be selectively arranged at different positions of the detection device, so that environment parameters of three different positions can be acquired simultaneously.

The first resistive element, the second resistive element and the third resistive element can be arranged at the same position, the environmental parameters at the same position are detected and collected, the screening or average value obtaining treatment is carried out according to the collected environmental parameters at the same position, the relatively accurate environmental parameters are obtained, and the effect of improving the accuracy of the collected environmental parameters is achieved.

In one possible design, the test signal includes a high level signal and a floating input signal, and the signal output circuit includes: the first signal output end is connected with the first end of the first resistive element; the second signal output end is connected with the second end of the first resistive element; the specific steps of the control device outputting the test signal to the variable resistance component through the signal output circuit include: one of the first signal output end and the second signal output end is controlled to output a high-level signal, and the other of the first signal output end and the second signal output end is controlled to output a floating input signal.

In this design, the signal output circuit includes a first signal output terminal connected to the first end of the first resistive element and a second signal output terminal connected to the second end of the second resistive element. The signal output circuit is arranged on the circuit board, and GPIO ports (general purpose input/output ports) which can be configured on the circuit board are used as a first signal output end and a second signal output end. The output signals sent by the first signal output end and the second signal output end comprise high-level signals and floating input signals, namely, two different signals can be sent through GPIO, and the signals can be switched by controlling the first signal output end and the second signal output end to output different signals, so that other switch chips are not required to be arranged in the detection circuit, and the production cost of the detection circuit is reduced.

In one possible design, the sampling circuit includes: a first sampling end connected to a first end of the first resistive element; a second sampling end connected to the second end of the first resistive element;

The step that the control device obtains the voltage value of the variable resistance component through the sampling circuit specifically comprises: based on the first signal output end output float input signal, the second signal output end output high level signal, gather the first voltage value of first resistive element first end through first sampling end, gather the second voltage value of first resistive element second end through the second sampling end.

In this design, the sampling circuit includes a first sampling end connected to the first end of the first resistive element and a second sampling end connected to the second end of the first resistive element. The first sampling end and the second sampling end are arranged on the circuit board, and an AIN port (analog input port) on the circuit board is used as the first sampling end and the second sampling end. The first sampling end can collect the voltage value of the first end position of the first resistive element, and the second sampling end can collect the voltage value of the second end position of the first resistive element. That is, the voltage value in the variable resistive component can be acquired by arranging the first sampling end and the second sampling end. The sampling end and the signal output end can be integrated on the same circuit board, no additional structure is needed, and the production cost is reduced.

When the first signal output end outputs a floating input signal, the circuit between the first signal output end and the first resistive element is equivalent to open circuit, the second signal output end outputs a high-level signal, current flows from the second signal output end to the second end of the first resistive element and is divided into two branches, wherein current of one branch flows from the second end to the first end of the first resistive element, flows through the second resistive element and then flows to the grounding end, and the current of the other branch flows from the first end to the second end of the third resistive element and then flows to the grounding end. When the first signal output end outputs a floating input signal and the second signal output end outputs a high-level signal, the variable resistance component circuit is equivalent to a series connection of a first resistance element and a second resistance element, and the third resistance element is connected with the first resistance element and the second resistance element in parallel. The first voltage value acquired through the first sampling end is the voltage value of the variable resistor. The first voltage value at the first end of the first resistive element is acquired through the first sampling end, the second voltage value acquired through the second sampling end is the voltage value of the third resistive element, and the ratio relation of the resistance values of the first resistive element and the second resistive element can be determined according to the first voltage value and the second voltage value.

In one possible design, the detection circuit further includes: the first end of the first voltage dividing resistor is connected with the first signal output end, and the second end of the first voltage dividing resistor is connected with the first end of the first resistive element.

In the design, the detection circuit further comprises a first voltage dividing resistor, wherein the first voltage dividing resistor is arranged between the first signal output end and the first resistive element, and plays a role in dividing voltage of a circuit between the first signal output end and the first resistive element, so that the circuit is prevented from being impacted by the excessive voltage.

In one possible design, the sampling circuit further includes: the third sampling end is connected with the first end of the first divider resistor; the step that the control device obtains the voltage value of the variable resistance component through the sampling circuit specifically comprises: based on the first signal output end outputting a high-level signal and the second signal output end outputting a floating input signal, collecting a third voltage value at the first end of the first resistive element through the first sampling end, collecting a fourth voltage value at the second end of the first resistive element through the second sampling end, and collecting a fifth voltage value at the first end of the first voltage dividing resistor through the third sampling end.

In this design, the sampling circuit further includes a third sampling end, where the third sampling end is also disposed on the current board, and an AIN port on the circuit board is selected as the third sampling end. The signal output end and the sampling end in the detection circuit can be integrated on the same circuit, no additional circuit structure is needed, and the production cost is reduced. The third sampling end is connected with the first end of the first voltage dividing resistor, and can collect the voltage value of the position of the first voltage dividing resistor.

When the second signal output end outputs a floating input signal, the second signal output end is equivalent to the second end of the first resistive element to be open-circuited, and the first signal output end outputs a high-level signal. The current flows through the first voltage dividing resistor from the first signal output end to the first end of the first resistive element to be divided into two branches. One of the branches sequentially flows through the first resistive element and the third resistive element and then reaches the ground terminal. The other branch passes through the second resistive element and reaches the ground terminal. When the first signal output end inputs a high-level signal and the second signal output end outputs a floating input signal, the circuit of the variable resistance component is equivalent to that the first resistance element and the third resistance element are connected in series, and the second resistance element is connected in parallel with the first resistance element and the third resistance element which are connected in series. The third voltage value collected by the first sampling end is the total voltage value of the current passing through the first voltage dividing resistor and the variable resistive element, the fourth voltage value collected by the second sampling end is the voltage value of the third resistive element, and the fifth voltage value collected by the third voltage breaking is the voltage value of the first voltage dividing resistor and the variable resistive element which are connected in series. The ratio relation of the resistances of the first resistive element and the third resistive element can be determined according to the third voltage value and the fourth voltage value, and the ratio relation of the resistances of the first resistive element and the first voltage dividing resistor can be determined according to the fifth voltage value.

It can be understood that when the first signal output end outputs a high-level signal, current not only flows through the variable resistive component, but also flows through the first voltage dividing resistor, so that the accuracy of detection is improved by taking the first voltage dividing resistor with a known resistance value as a calculated reference value without reference to a power supply voltage.

In one possible design, the step of determining the resistance values of the first, second and third resistive elements by the control device according to the test signal and the voltage value specifically includes: the resistance values of the first, second and third resistive elements are determined according to the first, second, third, fourth, fifth and first voltage dividing resistors.

In the design, the ratio relation between the first resistive element and the second resistive element can be determined according to the first voltage value and the second voltage value, the ratio relation between the first resistive element and the resistance value of the third resistive element can be obtained according to the third voltage value and the fourth voltage value, and the ratio relation between the first resistive element and the resistance value of the first voltage dividing resistor can be obtained according to the fifth voltage value. The resistance of the first voltage dividing resistor is a known resistance, so that the resistance of the first resistive element can be determined. And then the resistance values of the second resistive element and the third resistive element can be determined according to the ratio relation between the first resistive element and the second resistive element and the third resistive element. The resistance values of the first resistive element, the second resistive element and the third resistive element in the variable resistive component can be calculated and determined only by switching the types of signals output by the GPIO port output end on the circuit board.

In one possible design, the step of determining the resistance values of the first resistive element, the second resistive element and the third resistive element by the control device specifically includes: calculating according to the first voltage value and the second voltage value to obtain a first ratio parameter; calculating a second ratio parameter according to the third voltage value and the fourth voltage value; calculating a third ratio parameter according to the fourth voltage value and the fifth voltage value; calculating to obtain the resistance value of the first resistive element according to the first ratio parameter, the second ratio parameter, the third ratio parameter and the resistance value of the first voltage dividing resistor; calculating the resistance value of the second resistive element according to the resistance value of the first resistive element and the first ratio parameter; and calculating the resistance value of the third resistive element according to the resistance value of the first resistive element and the second ratio parameter.

In the design, the first ratio parameter is a ratio parameter of the resistances of the first resistive element and the second resistive element, the second ratio parameter is a ratio parameter of the resistances of the first resistive element and the third resistive element, and the ratio parameter of the resistances of the first resistive element and the first voltage dividing resistor is calculated according to the first ratio parameter, the second ratio parameter and the third ratio parameter, so that the resistance of the first resistive element is determined. And determining the resistance values of the second resistive element and the third resistive element according to the resistance value of the first resistive element, the first ratio parameter and the second ratio parameter. Compared with the prior art, the circuit for detecting the resistance value of the variable resistance component does not need to be provided with a multiplexing switch chip, so that the production cost is reduced, the calculation steps are few, the calculation amount of a system is reduced, the calculation efficiency is improved, the resistance value of the first voltage dividing resistor is used for replacing the power supply voltage as a reference value to calculate, calculation errors caused by consistency deviation existing in the power supply voltage are avoided, and the calculation accuracy is improved.

In one possible design, the control device is further configured to determine an environmental parameter value corresponding to the variable resistive component based on the resistance value of the variable resistive component.

In the design, the corresponding relation between the resistance value of the variable resistance component and the environmental parameter is pre-stored in the control device, and the specific value of the environmental parameter can be determined according to the resistance value of the variable resistance component.

In one possible design, the first, second, and third resistive elements include any one or a combination of a thermistor, a photoresistor, a varistor.

In this design, the first, second and third resistive elements may be any one of a thermistor, a photoresistor, a varistor. The first resistive element, the second resistive element and the third resistive element may be the same variable resistor or different variable resistors.

When different types of circuits are selected, the detection circuit can collect various environmental parameters at the same time.

In one possible design, the detection circuit further includes: and the first end of the second voltage dividing resistor is connected with the second signal output end, and the second end of the second voltage dividing resistor is connected with the second end of the first resistive element.

In the design, the second voltage dividing resistor is arranged at a position between the second signal output end and the first resistive element, and plays a role in dividing voltage of a circuit between the second signal output end and the first resistive element, so that the impact of the excessive voltage on the circuit is avoided.

It can be appreciated that the resistance of the second voltage dividing resistor is the same as that of the first voltage dividing resistor, so that the accuracy of calculating the variable resistance component is improved.

According to a second aspect of the present invention, there is provided a control method of a detection circuit, including: outputting a test signal to the variable resistive element through the signal output circuit; acquiring a voltage value of the variable resistance component through a sampling circuit; the resistance value of the variable resistive component is determined based on the test signal and the voltage value.

The control method provided by the invention comprises the following steps: the signal output circuit sends a test signal to the variable-resistance component, the sampling signal acquires the voltage value of the variable-resistance component through a sampling end connected with the variable-resistance component, and the resistance value of the variable-resistance component can be determined according to the sent test signal and the acquired voltage value. Compared with the scheme for detecting the resistance of the resistive component in the prior art, the resistance value of the variable resistive component can be determined without setting other chips, and the overall production cost of the detection circuit is reduced.

In addition, according to the control method of the detection circuit in the technical scheme provided by the invention, the control method also has the following additional technical characteristics:

in one possible design, the test signal includes a high level signal and a floating input signal, and the specific step of outputting the test signal to the variable resistive element through the signal output circuit includes: one of the first signal output end and the second signal output end is controlled to output a high-level signal, and the other of the first signal output end and the second signal output end is controlled to output a floating input signal.

In one possible design, the variable resistive component comprises: the method comprises the steps of obtaining a voltage value of a variable resistance component through a sampling circuit, wherein the first end of the first resistance component is connected with the first end of the second resistance component, the second end of the first resistance component is connected with the first end of the third resistance component, the second end of the second resistance component is connected with the second end of the third resistance component, and the method comprises the following steps: based on the first signal output end output float input signal, the second signal output end output high level signal, gather the first voltage value of first resistive element first end through first sampling end, gather the second voltage value of first resistive element second end through the second sampling end.

The sampling circuit comprises a first sampling end and a second sampling end, wherein the first sampling end is connected with the first end of the first resistive element, and the second sampling end is connected with the second end of the first resistive element. The first sampling end and the second sampling end are arranged on the circuit board, and an AIN port (analog input port) on the circuit board is used as the first sampling end and the second sampling end. The first sampling end can collect the voltage value of the first end position of the first resistive element, and the second sampling end can collect the voltage value of the second end position of the first resistive element. That is, the voltage value in the variable resistive component can be acquired by arranging the first sampling end and the second sampling end. The sampling end and the signal output end can be integrated on the same circuit board, no additional structure is needed, and the production cost is reduced.

In one possible design, the detection circuit further includes a first voltage dividing resistor, a first end of the first voltage dividing resistor is connected to the first signal output end, a second end of the first voltage dividing resistor is connected to the first end of the first resistive element, and the step of obtaining the voltage value of the variable resistive element through the sampling circuit specifically includes: based on the first signal output end outputting a high-level signal and the second signal output end outputting a floating input signal, collecting a third voltage value at the first end of the first resistive element through the first sampling end, collecting a fourth voltage value at the second end of the first resistive element through the second sampling end, and collecting a fifth voltage value at the first end of the first voltage dividing resistor through the third sampling end.

The sampling circuit further comprises a third sampling end, wherein the third sampling end is also arranged on the current board, and an AIN port on the circuit board is selected as the third sampling end. The signal output end and the sampling end in the detection circuit can be integrated on the same circuit, no additional circuit structure is needed, and the production cost is reduced. The third sampling end is connected with the first end of the first voltage dividing resistor, and can collect the voltage value of the position of the first voltage dividing resistor.

In one possible design, the step of determining the resistance values of the first, second and third resistive elements according to the test signal and the voltage value specifically includes: the resistance values of the first, second and third resistive elements are determined according to the first, second, third, fourth, fifth and first voltage dividing resistors.

In one possible design, the step of determining the resistance values of the first, second and third resistive elements specifically includes: calculating according to the first voltage value and the second voltage value to obtain a first ratio parameter; calculating a second ratio parameter according to the third voltage value and the fourth voltage value; calculating a third ratio parameter according to the fourth voltage value and the fifth voltage value; calculating to obtain the resistance value of the first resistive element according to the first ratio parameter, the second ratio parameter, the third ratio parameter and the resistance value of the first voltage dividing resistor; calculating the resistance value of the second resistive element according to the resistance value of the first resistive element and the first ratio parameter; and calculating the resistance value of the third resistive element according to the resistance value of the first resistive element and the second ratio parameter.

In one possible design, the control method further includes: and determining the environmental parameter value corresponding to the variable resistive component according to the resistance value of the variable resistive component.

In this design, the first, second and third resistive elements may be any one of a thermistor, a photoresistor, a varistor. The first resistive element, the second resistive element and the third resistive element may be the same type of variable resistor or different types of variable resistors.

According to a third aspect of the present invention there is provided a cooking appliance comprising: detection circuitry as in any of the possible designs described above; a memory; a processor, and a computer program stored on the memory and executable on the processor; the computer program, when executed by a processor, implements a method of controlling the detection circuit in any of the possible designs described above. Therefore, the detection circuit and the control method of the detection circuit in any of the above possible designs have all the advantages and will not be described in detail herein.

In one possible design, the cooking appliance further comprises a temperature probe, the variable resistive component in the detection circuit being disposed within the temperature probe; the circuit board, the signal output circuit, the sampling circuit and the control device in the detection circuit are arranged on the circuit board. In one possible design, the variable resistive component includes a first resistive element, a second resistive element, and a third resistive element. Wherein the first, second and third resistive elements are thermistors.

In this design, cooking utensil still includes temperature probe and circuit board, and the variable resistance subassembly in the detection circuitry sets up in temperature probe, and signal output circuit and the sampling circuit that is used for gathering variable resistance subassembly voltage value are set up on the circuit board for to variable resistance subassembly output test signal. The temperature probe is connected with a circuit board in the cooking utensil through a conductive line, and the variable resistive element in the temperature probe comprises a first resistive element, a second resistive element and a third resistive element. The three resistive elements are selected as thermistors, and the resistance values of the three resistive elements can be changed according to temperature. When a user uses the cooking appliance to heat and cook food, the temperature probe can be inserted into the food cooked by the cooking appliance after the cooking is suspended or the cooking is finished, the voltage values of the three resistive elements in the variable resistive assembly are obtained through the sampling circuit on the circuit board, and then the corresponding resistance values are determined according to the voltage values of the three resistive elements, so that the internal temperature value of the food inserted by the probe can be determined. Only the variable resistance component capable of collecting temperature is arranged in the probe, and the effect of accurately collecting the temperature of the food is realized by inserting the probe into the cooked food.

Three resistive elements can be selectively arranged at different positions of the probe, so that the temperature of different positions of the food material can be acquired. Specifically, three resistive elements are distributed along the length direction of the probe.

The three resistive elements can be arranged at the same position of the probe, and the temperature values acquired by the three resistive elements are averaged, so that the accuracy of temperature acquisition is improved.

It will be appreciated that the location of the variable resistive element may be set according to actual requirements. It will be appreciated that a variable resistive element comprising three resistive elements is optionally provided within the cooking cavity of the cooking appliance for capturing the ambient temperature within the cooking cavity.

According to a fourth aspect of the present invention a computer readable storage medium is presented, on which a computer program is stored which, when being executed by a processor, implements a method of controlling a detection circuit in any of the above possible designs, and thus has all the advantageous technical effects of the method of controlling a detection circuit in any of the above possible designs.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

fig. 1 shows a circuit diagram of a detection circuit of a first embodiment of the invention;

fig. 2 shows a circuit diagram of a detection circuit of a second embodiment of the invention;

Fig. 3 is a flow chart schematically showing a control method of the detection circuit according to the third embodiment of the present invention;

fig. 4 shows one of flow charts of a control method of a detection circuit according to a fourth embodiment of the present invention;

fig. 5 shows a second flow chart of a control method of the detection circuit according to the fourth embodiment of the invention;

fig. 6 shows a third flow chart of a control method of the detection circuit according to the fourth embodiment of the invention;

Fig. 7 shows a fourth flow chart of a control method of the detection circuit according to the fourth embodiment of the present invention;

Fig. 8 shows one of circuit diagrams of a detection circuit of a fifth embodiment of the present invention;

fig. 9 shows a second circuit diagram of the detection circuit of the fifth embodiment of the present invention;

fig. 10 shows a schematic block diagram of a cooking appliance of a sixth embodiment of the present invention.

The correspondence between the reference numerals and the component names in fig. 1, 2, 8, 9 and 10 is:

100 detection circuit, 110 variable resistive component, 112 first resistive element, 114 second resistive element, 116 third resistive element, 120 signal output circuit, 122 first signal output terminal, 124 second signal output terminal, 130 sampling circuit, 132 first sampling terminal, 134 second sampling terminal, 136 third sampling terminal, 140 control device, 150 first voltage dividing resistor, 160 second voltage dividing resistor, 200 cooking appliance, 202 processor, 204 memory.

Detailed Description

In order that the above-recited objects, features and advantages of the present invention will be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description. It should be noted that, without conflict, the embodiments of the present invention and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those described herein, and therefore the scope of the present invention is not limited to the specific embodiments disclosed below.

A detection circuit, a control method of the detection circuit, a cooking appliance, and a computer-readable storage medium according to some embodiments of the present invention are described below with reference to fig. 1 to 10.

Embodiment one:

As shown in fig. 1, in one embodiment of the present invention, there is provided a detection circuit 100 including: a variable resistive element 110, a signal output circuit 120, a variable resistive element 110, a sampling circuit 130, and a control device 140. The output end of the signal output circuit 120 and the sampling end of the sampling circuit 130 are connected with the variable resistive component 110, the control device 140 is connected with the signal output circuit 120 and the sampling circuit 130, and the control device 140 outputs a test signal to the variable resistive component 110 through the signal output circuit 120; acquiring a voltage value of the variable resistive component 110 through the sampling circuit 130; the resistance value of the variable resistive component 110 is determined based on the test signal and the voltage value.

Wherein the variable resistance component is configured to change the resistance value in accordance with a change in the environmental parameter.

In this embodiment, the variable resistive element 110 includes at least one variable resistive element, the output terminal of the signal output terminal circuit and the sampling terminal of the sampling circuit 130 are connected to the variable resistive element 110, the signal output circuit 120 can send a test signal to the variable resistive element 110, the sampling signal collects a voltage value of the variable resistive element 110 through the sampling terminal connected to the variable resistive element 110, and the resistance value of the variable resistive element 110 can be determined according to the sent test signal and the collected voltage value. The test signal is sent through the signal output end, the voltage value of the corresponding position is collected through the sampling circuit 130, and the resistance value of the variable resistive element can be determined according to the voltage value and the test signal. Compared with the scheme of detecting the resistance of the variable resistance component 110 in the prior art, the resistance value of the variable resistance component 110 can be determined without arranging other chips, and the overall production cost of the detection circuit 100 is reduced.

The resistance value of the variable resistive element 110 changes according to the change of the environmental parameter, enabling the detection of the environmental parameter using the detection circuit 100 of the present invention. In particular, the variable resistive component 110 is disposed at a location where an environmental parameter is desired to be sensed.

In a specific embodiment, only one resistive element is disposed in the variable resistive component 110, and the test signal includes a current signal, so that the resistance value of the resistive element can be directly determined directly through the current signal and the collected voltage value.

In another embodiment, a plurality of resistive elements are disposed in the variable resistive element 110, and the test signal includes a current signal, and the total resistance value of the plurality of connected resistive elements can be directly determined through the current signal and the collected voltage value.

In a specific embodiment, if the temperature of the food to be cooked in the cooking appliance needs to be detected, the variable resistance component 110 is arranged at the sampling end of the temperature probe, the temperature probe stretches into the food to be detected, the resistance value of the variable resistance component 110 changes correspondingly according to the temperature of the food, and the detected temperature of the food to be cooked is determined according to the corresponding relation between the resistance value of the variable resistance component 110 and the temperature parameter obtained by calculation. A fast detection of an environmental parameter by the detection circuit 100 is achieved.

Embodiment two:

As shown in fig. 2, in one embodiment of the present invention, there is provided a detection circuit 100 including: a variable resistive element 110, a signal output circuit 120, a variable resistive element 110, a sampling circuit 130, and a control device 140.

The variable resistive component 110 includes: the first, second and third resistive elements 112, 114, 116 are sequentially terminated by the first, second and third resistive elements 112, 114, 116. Specifically, the first end of the second resistive element 114 is connected to the first end of the first resistive element 112; a third resistive element 116, a first end of the third resistive element 116 being coupled to a second end of the first resistive element 112, a second end of the third resistive element 116 being coupled to a second end of the second resistive element 114, the second end of the third resistive element 116 being coupled to ground.

In this embodiment, by providing three resistive elements in the variable resistive component 110, an environmental parameter that can be detected simultaneously is achieved, the range over which the detection circuit 100 collects environmental parameters is improved, and the accuracy with which the environmental parameters are collected.

In one particular embodiment, the first resistive element 112, the second resistive element 114, and the third resistive element 116 are disposed at different locations of the detection device. The environment parameters of three different positions are collected simultaneously.

In another embodiment, the first resistive element 112, the second resistive element 114 and the third resistive element 116 are disposed at the same position, the environmental parameters at the same position are detected and collected, and the screening or averaging process is performed according to the collected environmental parameters at the same position, so as to obtain relatively accurate environmental parameters, and achieve the effect of improving the accuracy of collecting the environmental parameters.

In any of the above embodiments, the detection circuit 100 further includes: the first voltage dividing resistor 150, a first end of the first voltage dividing resistor 150 is connected to the first signal output terminal 122, and a second end of the first voltage dividing resistor 150 is connected to the first end of the first resistive element 112.

The signal output circuit 120 includes a first signal output terminal 122 and a second signal output terminal 124, wherein the signals emitted from the first signal output terminal 122 and the second signal output terminal 124 include a high level signal and a floating input signal. The first signal output 122 is coupled to a first end of the first resistive element 112 and the second signal output 124 is coupled to a second end of the first resistive element 112.

The sampling circuit 130 includes a first sampling terminal 132, a second sampling terminal 134, and a third sampling terminal 136. The first sampling end 132 is connected to a first end of the first resistive element 112, the second sampling end 134 is connected to a second end of the first resistive element 112, and the third sampling end 136 is connected to a first end of the first voltage dividing resistor 150.

In this embodiment, the signal output circuit 120 includes a first signal output 122 and a second signal output 124, the first signal output 122 being coupled to a first end of the first resistive element 112 and the second signal output 124 being coupled to a second end of the second resistive element 114. The signal output circuit 120 is disposed on a circuit board, and GPIO ports (general purpose input/output ports) configurable on the circuit board are used as a first signal output terminal 122 and a second signal output terminal 124. The output signals sent by the first signal output end 122 and the second signal output end 124 comprise a high-level signal and a floating input signal, namely, two different signals can be sent through GPIO, and the switching of the signals can be realized by controlling the first signal output end 122 and the second signal output end 124 to output different signals, so that other switch chips are not required to be arranged in the detection circuit 100, and the production cost of the detection circuit 100 is reduced. An AIN port (analog input port) on the circuit board is used as a first sampling end 132, a second sampling end 134 and a third sampling end 136. The first sampling end 132 is capable of collecting a voltage value at a first end position of the first resistive element 112, and the second sampling end 134 is capable of collecting a voltage value at a second end position of the first resistive element 112. I.e. by providing a first sampling end 132 and a second sampling end 134, the voltage values in the variable resistive component 110 can be acquired. The sampling end and the signal output end can be integrated on the same circuit board, no additional structure is needed, and the production cost is further reduced.

The first voltage dividing resistor 150 is disposed between the first signal output end 122 and the first resistive element 112, and plays a role in dividing voltage of a circuit between the first signal output end 122 and the first resistive element 112, so as to avoid impact of an excessive voltage on the circuit.

In the above embodiment, the step of acquiring the voltage value of the variable resistive element 110 by the sampling circuit 130 specifically includes:

When the first signal output end 122 outputs the floating input signal and the second signal output end 124 outputs the high level signal, the control device 140 collects a first voltage value at the first end of the first resistive element 112 through the first sampling end 132 and collects a second voltage value at the second end of the first resistive element 112 through the second sampling end 134; the high level signal is output at the first signal output terminal 122 and the floating input signal is output at the second signal output terminal 124, the third voltage value at the first end of the first resistive element 112 is collected through the first sampling terminal 132, the fourth voltage value at the second end of the first resistive element 112 is collected through the second sampling terminal 134, and the fifth voltage value at the first end of the first voltage dividing resistor 150 is collected through the third sampling terminal 136.

In this embodiment, when the first signal output terminal 122 outputs the floating input signal, the circuit between the first signal output terminal 122 and the first resistive element 112 is equivalent to open circuit, the second signal output terminal 124 outputs the high signal, and the current flows from the second signal output terminal 124 to the second terminal of the first resistive element 112 and is divided into two branches, wherein one branch current flows from the second terminal to the first terminal of the first resistive element 112, flows through the second resistive element 114 and then flows to the ground terminal, and the other branch current flows from the first terminal to the second terminal of the third resistive element 116 and then flows to the ground terminal. That is, when the first signal output terminal 122 outputs the floating input signal and the second signal output terminal 124 outputs the high level signal, the circuit of the variable resistive element 110 is equivalent to the series connection of the first resistive element 112 and the second resistive element 114, and the third resistive element 116 is connected in parallel with the first resistive element 112 and the second resistive element 114. The first voltage value collected by the first sampling end 132 is the voltage value of the variable resistor. A first voltage value at the first end of the first resistive element 112 is collected through the first sampling end 132, a second voltage value collected through the second sampling end 134 is a voltage value of the third resistive element 116, and a ratio relationship between the resistance values of the first resistive element 112 and the second resistive element 114 can be determined according to the first voltage value and the second voltage value.

When the second signal output end 124 outputs the floating input signal, the second signal output end 124 is equivalent to the second end of the first resistive element 112 being open circuit, and the first signal output end 122 outputs the high level signal. The current flows from the first signal output terminal 122 through the first voltage dividing resistor 150 to the first end of the first resistive element 112 to divide into two branches. One of the branches flows through the first resistive element 112 and the third resistive element 116 in sequence, and then reaches the ground. The other branch of the branches passes through the second resistive element 114 and reaches the ground. That is, when the first signal output terminal 122 inputs a high level signal and the second signal output terminal 124 outputs a floating input signal, the circuit of the variable resistive element 110 is equivalent to the series connection of the first resistive element 112 and the third resistive element 116, and the second resistive element 114 is connected in parallel with the series connection of the first resistive element 112 and the third resistive element 116. The third voltage value collected by the first sampling end 132 is the total voltage value of the current passing through the first voltage dividing resistor 150 and the variable resistive element, the fourth voltage value collected by the second sampling end 134 is the voltage value of the third resistive element 116, and the fifth voltage value collected by the third voltage breaking is the voltage value of the first voltage dividing resistor 150 connected in series with the variable resistive element. The ratio relationship of the resistances of the first resistive element 112 and the third resistive element 116 can be determined according to the third voltage value and the fourth voltage value, and the ratio relationship of the resistances of the first resistive element 112 and the first voltage dividing resistor 150 can be determined according to the fifth voltage value.

In any of the above embodiments, the step of determining the resistance values of the first resistive element 112, the second resistive element 114 and the third resistive element 116 by the control device 140 according to the test signal and the voltage value specifically includes: the resistance values of the first resistive element 112, the second resistive element 114, and the third resistive element 116 are determined according to the first voltage value, the second voltage value, the third voltage value, the fourth voltage value, the fifth voltage value, and the resistance value of the first voltage dividing resistor 150.

The specific calculation mode is that a first ratio parameter is calculated according to a first voltage value and a second voltage value; calculating a second ratio parameter according to the third voltage value and the fourth voltage value; calculating a third ratio parameter according to the fourth voltage value and the fifth voltage value; calculating to obtain the resistance value of the first resistive element 112 according to the first ratio parameter, the second ratio parameter, the third ratio parameter and the resistance value of the first voltage dividing resistor 150; calculating the resistance value of the second resistive element 114 according to the resistance value of the first resistive element 112 and the first ratio parameter; the resistance of the third resistive element 116 is calculated based on the resistance of the first resistive element 112 and the second ratio parameter.

In this embodiment, the ratio relationship between the first resistive element 112 and the second resistive element 114 can be determined according to the first voltage value and the second voltage value, the ratio relationship between the resistance values of the first resistive element 112 and the third resistive element 116 can be obtained according to the third voltage value and the fourth voltage value, and the ratio relationship between the resistance values of the first resistive element 112 and the first voltage dividing resistor 150 can be obtained according to the fifth voltage value. The resistance of the first voltage dividing resistor 150 is a known resistance, so that the resistance of the first resistive element 112 can be determined. The resistance values of the second resistive element 114 and the third resistive element 116 can be determined according to the ratio relationship between the first resistive element 112 and the second resistive element 114 and the third resistive element 116. The resistance values of the first resistive element 112, the second resistive element 114 and the third resistive element 116 in the variable resistive element 110 can be calculated and determined by only switching the types of the output signals of the GPIO port output ends on the circuit board.

The first ratio parameter is a ratio parameter of the resistances of the first resistive element 112 and the second resistive element 114, the second ratio parameter is a ratio parameter of the resistances of the first resistive element 112 and the third resistive element 116, and the ratio parameter of the resistances of the first resistive element 112 and the first voltage dividing resistor 150 is calculated according to the first ratio parameter, the second ratio parameter and the third ratio parameter, so as to determine the resistance of the first resistive element 112. The resistance values of the second resistive element 114 and the third resistive element 116 are determined according to the resistance value of the first resistive element 112, the first ratio parameter and the second ratio parameter. Compared with the prior art, the circuit for detecting the resistance value of the variable resistance component 110 does not need to be provided with a multiplexing switch chip, so that the production cost is reduced, the calculation steps are fewer, the calculation amount of a system is reduced, the calculation efficiency is improved, the resistance value of the first voltage dividing resistor 150 is used for replacing the power supply voltage as a reference value to calculate, calculation errors caused by consistency deviation existing in the power supply voltage are avoided, and the calculation accuracy is improved.

In any of the above embodiments, the control device 140 is further configured to determine an environmental parameter value corresponding to the variable resistive element 110 according to the resistance value of the variable resistive element 110.

In this embodiment, the corresponding relationship between the resistance value of the variable resistive element 110 and the environmental parameter is pre-stored in the control device 140, and a specific value of the environmental parameter can be determined according to the resistance value of the variable resistive element 110.

In any of the above embodiments, the first, second, and third resistive elements 112, 114, 116 comprise any one of a thermistor, photoresistor, piezoresistor, or combination thereof.

In this embodiment, the first resistive element 112, the second resistive element 114, and the third resistive element 116 may be any one of a thermistor, a photoresistor, and a varistor. The first resistive element 112, the second resistive element 114, and the third resistive element 116 may be the same variable resistor or different variable resistors.

When different kinds of circuits are selected, it is realized that a plurality of environmental parameters can be collected simultaneously by the detection circuit 100 of the present invention.

In any of the above embodiments, the detection circuit 100 further includes: and a second voltage divider resistor 160, the first end of the second voltage divider resistor 160 being connected to the second signal output terminal 124, and the second end of the second voltage divider resistor 160 being connected to the second end of the first resistive element 112.

In this embodiment, the second voltage dividing resistor 160 is disposed between the second signal output end 124 and the first resistive element 112, and performs a voltage dividing function on the circuit between the second signal output end 124 and the first resistive element 112, so as to avoid the impact of the excessive voltage on the circuit.

It can be appreciated that the resistance of the second voltage dividing resistor 160 is the same as that of the first voltage dividing resistor 150, which improves the accuracy of calculating the variable resistive element 110.

Embodiment III:

as shown in fig. 3, another embodiment of the present invention provides a control method of a detection circuit, including:

Step S302, outputting a test signal to the variable resistive element through a signal output circuit;

Step S304, obtaining a voltage value of the variable resistive component through a sampling circuit;

step S306, the resistance value of the variable resistive component is determined according to the test signal and the voltage value.

In this embodiment, the signal output circuit sends a test signal to the variable resistive element, the sampling signal collects a voltage value of the variable resistive element through a sampling end connected to the variable resistive element, and the resistance value of the variable resistive element can be determined according to the sent test signal and the collected voltage value. Compared with the scheme for detecting the resistance of the resistive component in the prior art, the resistance value of the variable resistive component can be determined without setting other chips, and the overall production cost of the detection circuit is reduced.

Embodiment four:

As shown in fig. 4, a further embodiment of the present invention provides a control method of a detection circuit, which is used for the detection circuit in the third embodiment, the control method including:

Step S402, one of the first signal output end and the second signal output end is controlled to output a high-level signal, and the other of the first signal output end and the second signal output end is controlled to output a floating input signal;

Step S404, obtaining a voltage value of the variable resistive component through a sampling circuit;

step S406, determining the resistance value of the variable resistive component according to the test signal and the voltage value.

In this embodiment, the signal output circuit includes a first signal output terminal connected to the first end of the first resistive element and a second signal output terminal connected to the second end of the second resistive element. The signal output circuit is arranged on the circuit board, and GPIO ports (general purpose input/output ports) which can be configured on the circuit board are used as a first signal output end and a second signal output end. The output signals sent by the first signal output end and the second signal output end comprise high-level signals and floating input signals, namely, two different signals can be sent through GPIO, and the signals can be switched by controlling the first signal output end and the second signal output end to output different signals, so that other switch chips are not required to be arranged in the detection circuit, and the production cost of the detection circuit is reduced.

As shown in fig. 5, the step of obtaining the voltage value of the variable resistive element by the sampling circuit in the control method specifically includes:

Step S502, determining that the first signal output end outputs a floating input signal and the second signal output end outputs a high-level signal;

Step S504, collecting a first voltage value at a first end of a first resistive element through a first sampling end;

in step S506, a second voltage value at a second end of the first resistive element is acquired through a second sampling end.

In this embodiment, when the first signal output end outputs the floating input signal, the circuit between the first signal output end and the first resistive element is equivalent to open circuit, the second signal output end outputs a high-level signal, and the current flows from the second signal output end to the second end of the first resistive element and is divided into two branches, wherein one branch current flows from the second end to the first end of the first resistive element, flows through the second resistive element and then flows to the ground, and the other branch current flows from the first end to the second end of the third resistive element and then flows to the ground. When the first signal output end outputs a floating input signal and the second signal output end outputs a high-level signal, the variable resistance component circuit is equivalent to a series connection of a first resistance element and a second resistance element, and the third resistance element is connected with the first resistance element and the second resistance element in parallel. The first voltage value acquired through the first sampling end is the voltage value of the variable resistor. The first voltage value at the first end of the first resistive element is acquired through the first sampling end, the second voltage value acquired through the second sampling end is the voltage value of the third resistive element, and the ratio relation of the resistance values of the first resistive element and the second resistive element can be determined according to the first voltage value and the second voltage value.

As shown in fig. 6, the step of obtaining, by the sampling circuit, the voltage value of the variable resistive element in the control method further specifically includes:

Step S602, determining that the first signal output end outputs a high-level signal and the second signal output end outputs a floating input signal;

step S604, collecting a fourth voltage value at a second end of the first resistive element through a second sampling end;

in step S606, a fifth voltage value at the first end of the first voltage dividing resistor is collected through the third sampling end.

In this embodiment, when the second signal output terminal outputs the floating input signal, the second signal output terminal is equivalent to the second terminal of the first resistive element being open-circuited, and the first signal output terminal outputs the high-level signal. The current flows through the first voltage dividing resistor from the first signal output end to the first end of the first resistive element to be divided into two branches. One of the branches sequentially flows through the first resistive element and the third resistive element and then reaches the ground terminal. The other branch passes through the second resistive element and reaches the ground terminal. When the first signal output end inputs a high-level signal and the second signal output end outputs a floating input signal, the circuit of the variable resistance component is equivalent to that the first resistance element and the third resistance element are connected in series, and the second resistance element is connected in parallel with the first resistance element and the third resistance element which are connected in series. The third voltage value collected by the first sampling end is the total voltage value of the current passing through the first voltage dividing resistor and the variable resistive element, the fourth voltage value collected by the second sampling end is the voltage value of the third resistive element, and the fifth voltage value collected by the third voltage breaking is the voltage value of the first voltage dividing resistor and the variable resistive element which are connected in series. The ratio relation of the resistances of the first resistive element and the third resistive element can be determined according to the third voltage value and the fourth voltage value, and the ratio relation of the resistances of the first resistive element and the first voltage dividing resistor can be determined according to the fifth voltage value.

As shown in fig. 7, the step of determining the resistance values of the first resistive element, the second resistive element 114 and the third resistive element 116 according to the test signal and the voltage value specifically includes: the resistance values of the first, second, and third resistive elements 114, 116 are determined according to the first, second, third, fourth, fifth, and first voltage dividing resistances.

The method comprises the following specific steps of:

step S702, calculating to obtain a first ratio parameter according to the first voltage value and the second voltage value;

Step S704, calculating a second ratio parameter according to the third voltage value and the fourth voltage value; calculating a third ratio parameter according to the fourth voltage value and the fifth voltage value;

Step S706, calculating the resistance value of the first resistive element according to the first ratio parameter, the second ratio parameter, the third ratio parameter and the resistance value of the first voltage dividing resistor;

Step S708, calculating the resistance value of the second resistive element according to the resistance value of the first resistive element and the first ratio parameter;

In step S710, the resistance value of the third resistive element is calculated according to the resistance value of the first resistive element and the second ratio parameter.

In this embodiment, the ratio relationship between the first resistive element and the second resistive element can be determined according to the first voltage value and the second voltage value, the ratio relationship between the first resistive element and the resistance value of the third resistive element can be obtained according to the third voltage value and the fourth voltage value, and the ratio relationship between the first resistive element and the resistance value of the first voltage dividing resistor can be obtained according to the fifth voltage value. The resistance of the first voltage dividing resistor is a known resistance, so that the resistance of the first resistive element can be determined. And then the resistance values of the second resistive element and the third resistive element can be determined according to the ratio relation between the first resistive element and the second resistive element and the third resistive element. The resistance values of the first resistive element, the second resistive element and the third resistive element in the variable resistive component can be calculated and determined only by switching the types of signals output by the GPIO port output end on the circuit board.

The first ratio parameter is a ratio parameter of the resistances of the first resistive element and the second resistive element, the second ratio parameter is a ratio parameter of the resistances of the first resistive element and the third resistive element, and the ratio parameter of the resistances of the first resistive element and the first voltage dividing resistor is calculated according to the first ratio parameter, the second ratio parameter and the third ratio parameter, so that the resistance of the first resistive element is determined. And determining the resistance values of the second resistive element and the third resistive element according to the resistance value of the first resistive element, the first ratio parameter and the second ratio parameter. Compared with the prior art, the circuit for detecting the resistance value of the variable resistance component does not need to be provided with a multiplexing switch chip, so that the production cost is reduced, the calculation steps are few, the calculation amount of a system is reduced, the calculation efficiency is improved, the resistance value of the first voltage dividing resistor is used for replacing the power supply voltage as a reference value to calculate, calculation errors caused by consistency deviation existing in the power supply voltage are avoided, and the calculation accuracy is improved.

In any of the foregoing embodiments, the control method further includes: and determining the environmental parameter value corresponding to the variable resistive component according to the resistance value of the variable resistive component.

In this embodiment, the correspondence between the resistance value of the variable resistive element and the environmental parameter is pre-stored in the control device, and a specific value of the environmental parameter can be determined according to the resistance value of the variable resistive element.

Wherein the first, second and third resistive elements comprise any one or combination of a thermistor, photoresistor, varistor. The first resistive element, the second resistive element and the third resistive element may be the same type of variable resistor or different types of variable resistors.

In a specific embodiment, when the first resistive element, the second resistive element and the third resistive element select different types of resistors, the detection circuit can collect multiple environmental parameters simultaneously.

Fifth embodiment:

A complete embodiment of the present invention provides a detection circuit 100 and a control method, wherein the detection circuit 100 comprises:

the variable resistance component includes a first resistive element 112, a second resistive element 114, and a third resistive element 116.

The signal output circuit 120 includes a first signal output 122 and a second signal output 124, the first signal output 122 being connected between the first resistive element 112 and the second resistive element 114, the second signal output 124 being connected between the first set of resistive elements and the third resistive element 116.

The voltage dividing resistor includes a first voltage dividing resistor 150 and a second voltage dividing resistor 160, the first voltage dividing resistor 150 is disposed between the first signal output end 122 and the first resistive element 112, and the second voltage dividing resistor 160 is disposed between the second signal output end 124 and the first resistive element 112.

Sampling circuit 130, sampling circuit 130 includes a first sampling end 132, a second sampling end 134, and a third sampling end 136. The first sampling end 132 is connected between the first resistive element 112 and the second resistive element 114, the second sampling end 134 is connected between the first resistive element 112 and the third resistive element 116, and the third sampling end 136 is connected between the first signal output end 122 and the first voltage dividing resistor 150.

The control device 140 is connected with the signal output circuit 120 and the sampling circuit 130, and the control device 140 executes a control method to realize that the control signal output circuit 120 outputs a test signal, collects a voltage value through the sampling circuit 130, and calculates the resistance value of each resistive element in the variable resistance component according to the voltage value and the test signal.

The collected voltage value is specifically divided into two stages.

(1) The first signal output terminal 122 is controlled to output a floating input signal, and the second signal output terminal 124 is controlled to output a high level signal.

As shown in fig. 8, the circuit between the first signal output terminal 122 and the first resistive element 112 is equivalent to an open circuit, the second signal output terminal 124 outputs a high level signal, and the current flows from the second signal output terminal 124 to the second terminal of the first resistive element 112 and is divided into two branches, wherein one branch current flows from the second terminal to the first terminal of the first resistive element 112, flows through the second resistive element 114 and then flows to the ground terminal, and the other branch current flows from the first terminal to the second terminal of the third resistive element 116 and then flows to the ground terminal. The voltage values of the point A and the point B are collected and are respectively U _a1 and U _b1, and the following equation can be obtained:

As can be seen from the above equation, R _b＝c₁R_a,

Wherein R _a is the resistance value of the first resistive element 112, rb is the resistance value of the second resistive element 114, U _a1 is the first voltage value, U _b1 is the second voltage value, and c ₁ is the ratio of the resistance values of the first resistive element 112 and the second resistive element 114.

The ratio parameter of the resistance values of the first resistive element 112 and the second resistive element 114 can be determined by the first voltage value and the second voltage value.

(2) The first signal output terminal 122 is controlled to output a high level signal, and the second signal output terminal 124 is controlled to output a floating signal.

As shown in fig. 9, the second signal output terminal 124 is equivalent to an open circuit from the second terminal of the first resistive element 112, and the first signal output terminal 122 outputs a high level signal. The current flows from the first signal output terminal 122 through the first voltage dividing resistor 150 to the first end of the first resistive element 112 to divide into two branches. One of the branches flows through the first resistive element 112 and the third resistive element 116 in sequence, and then reaches the ground. The other branch of the branches passes through the second resistive element 114 and reaches the ground.

The voltage values of the point A, the point B and the point C are collected and are respectively U _a2、U_b2 and U ₀₂, and the following equation can be obtained:

From the above equation, R _c＝c₂R_a;

/>

(R_a+c₂R_a)//c₁R_a＝c₃R₀

r _a has the formula of

Wherein, R _a is the resistance value of the first resistive element 112, rb is the resistance value of the second resistive element 114, R _c is the resistance value of the third resistive element 116, R ₀ is the resistance value of the first voltage dividing resistor 150, U _a1 is the first voltage value, U _b1 is the second voltage value, U _a2 is the third voltage value, U _b2 is the fourth voltage value, U ₀₂ is the fifth voltage value, c ₁ is the ratio parameter of the resistance values of the first resistive element 112 and the second resistive element 114, c ₂ is the ratio parameter of the first resistive element 112 and the third resistive element 116, and c ₃ is the ratio parameter of the first resistive element 112 and the first voltage dividing resistor 150.

The resistance value R _a of the first resistive element 112 can be determined by the above equation, and the resistance value R _b of the second resistive element 114 and the resistance value R _c of the third resistive element 116 can be determined from the resistance value R _a.

In this embodiment, by configuring two GPIO ports of the circuit board as signal output terminals capable of outputting a high level signal and a floating input signal, and configuring three AIN ports as sampling terminals, the resistance in the variable resistance component can be calculated without additionally providing a multiplexing switch chip. The circuit cost is reduced, the processing time of the singlechip is shortened, the influence of consistency deviation of power supply voltage on the temperature measurement precision is eliminated, and the temperature detection precision is improved.

Example six:

As shown in fig. 10, an embodiment of the present invention provides a cooking appliance 200 including the detection circuit 100 and the memory 204 as in any of the above embodiments; a processor 202, and a computer program stored on the memory 204 and executable on the processor 202; the computer program, when executed by a processor, implements the method of controlling the detection circuit in any of the embodiments described above. Therefore, the detection circuit 100 and the control method of the detection circuit in any of the above embodiments have all the advantages and are not described in detail herein. Therefore, the control device of the cooking appliance has all the beneficial technical effects of any one of the embodiments, and is not described herein.

In the above embodiment, the variable resistive component includes the first resistive element, the second resistive element 114, and the third resistive element 116, where the first resistive element, the second resistive element 114, and the third resistive element 116 are all thermistors.

In the above embodiment, the cooking appliance 200 further includes a temperature probe in which the variable resistive element 110 in the detection circuit 100 is disposed, and a circuit board on which the signal output circuit 120 for outputting a test signal to the variable resistive element 110 and the sampling circuit 130 for collecting a voltage value of the variable resistive element 110 are disposed.

In this embodiment, the temperature probe is connected to a circuit board within the cooking appliance 200 by conductive traces, and the variable resistive elements in the temperature probe include a first resistive element 112, a second resistive element 114, and a third resistive element 116. The three resistive elements are selected as thermistors, and the resistance values of the three resistive elements can be changed according to temperature. When a user uses the cooking appliance 200 to heat and cook food, the temperature probe can be inserted into the food cooked by the cooking appliance 200 after the cooking is suspended or the cooking is finished, the voltage values of the three resistive elements in the variable resistive assembly 110 are obtained through the sampling circuit 130 on the circuit board, and then the corresponding resistance values are determined according to the voltage values of the three resistive elements, so that the internal temperature value of the food inserted by the probe can be determined. Only the variable resistive assembly 110 capable of collecting temperature is provided in the probe, and the effect of accurately collecting the temperature of the food material is achieved by inserting the probe into the cooked food material.

In a specific embodiment, three resistive elements are disposed at different positions of the probe, enabling the collection of temperatures at different positions of the food material. Specifically, three resistive elements are distributed along the length direction of the probe. The probe is inserted into the food material to collect temperature values of three different positions of the food material.

In another specific embodiment, three resistive elements are arranged at the same position of the probe, and the temperature values acquired by the three resistive elements are averaged, so that the accuracy of temperature acquisition is improved.

It will be appreciated that the location of the variable resistive element may be set according to actual requirements. It will be appreciated that a variable resistive element comprising three resistive elements is selected to be disposed within the cooking cavity of cooking appliance 200 for capturing the ambient temperature within the cooking cavity.

In a specific embodiment, the processor 202 and the memory 204 of the cooking appliance 200 can be integrated on a circuit board and the control device 140 in the detection circuit 100 is integrated within the processor 202.

In another embodiment, the processor 202 and the memory 204 of the cooking appliance 200 are provided separately from the circuit board, and the processor 202 and the memory 204 are connected to the circuit board through conductive lines.

It can be understood that the variable resistance component can be replaced by other circuits for detecting resistance, and the three resistances can be detected under the condition that the three resistances are not detached by connecting the three other resistances into a triangle, so that the method is simple and convenient.

Embodiment seven:

An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which when executed by a processor, implements the control method of the detection circuit in any of the above embodiments, thereby having all the advantageous technical effects of the control method of the detection circuit in any of the above embodiments.

In the present invention, the term "plurality" means two or more, unless explicitly defined otherwise. The terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, the terms "one embodiment," "some embodiments," "particular embodiments," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A detection circuit, comprising:

a variable resistive component configured to change a resistance value according to a change in an environmental parameter;

The output end of the signal output circuit is connected with the variable resistance component;

the sampling end of the sampling circuit is connected with the variable resistance component;

A control device connected to the signal output circuit and the sampling circuit, the control device configured to output a test signal to the variable resistive element through the signal output circuit;

acquiring a voltage value of the variable resistive component through the sampling circuit;

determining a resistance value of the variable resistive component from the test signal and the voltage value;

The variable resistive component comprises:

a first resistive element;

a second resistive element, a first end of the second resistive element being connected to a first end of the first resistive element;

a third resistive element having a first end connected to the second end of the first resistive element, a second end connected to the second end of the second resistive element, and a second end connected to a ground terminal;

The test signal includes a high level signal and a floating input signal, and the signal output circuit includes:

a first signal output connected to a first end of the first resistive element;

a second signal output connected to a second end of the first resistive element;

The specific steps of the control device outputting a test signal to the variable resistance component through the signal output circuit include:

Controlling one of the first signal output terminal and the second signal output terminal to output the high level signal, and controlling the other of the first signal output terminal and the second signal output terminal to output the floating input signal;

The detection circuit further comprises a first voltage dividing resistor, wherein a first end of the first voltage dividing resistor is connected with the first signal output end, and a second end of the first voltage dividing resistor is connected with the first end of the first resistive element;

The sampling circuit includes:

A first sampling end connected to a first end of the first resistive element;

a second sampling end connected to a second end of the first resistive element;

the third sampling end is connected with the first end of the first voltage dividing resistor;

The step of the control device obtaining the voltage value of the variable resistance component through the sampling circuit specifically comprises the following steps:

Based on the first signal output end, outputting a floating input signal, the second signal output end outputs a high-level signal, a first voltage value at a first end of the first resistive element is acquired through the first sampling end, a second voltage value at a second end of the first resistive element is acquired through the second sampling end, based on the first signal output end outputs the high-level signal and the second signal output end outputs the floating input signal, a third voltage value at the first end of the first resistive element is acquired through the first sampling end, a fourth voltage value at the second end of the first resistive element is acquired through the second sampling end, and a fifth voltage value at the first end of the first voltage dividing resistor is acquired through the third sampling end;

determining the resistance value of the variable resistance component according to the test signal and the voltage value specifically comprises the following steps:

Determining a ratio relationship of the first resistive element and the second resistive element according to a first voltage value at a first end of the first resistive element and a second voltage value at a second end of the first resistive element, determining a ratio relationship of the first resistive element and the third resistive element according to a third voltage value at the first end of the first resistive element and a fourth voltage value at the second end of the first resistive element, determining a ratio relationship of the first resistive element and the first resistive element according to a fifth voltage value at the first end of the first voltage dividing resistor, determining a resistance of the first resistive element according to a resistance of the first voltage dividing resistor, and determining a resistance of the second resistive element and the third resistive element according to a ratio relationship between the first resistive element and the second resistive element and the third resistive element.

2. The detection circuit according to claim 1, wherein the control means determines the resistance values of the first, second and third resistive elements, in particular comprising:

calculating according to the first voltage value and the second voltage value to obtain a first ratio parameter;

calculating a second ratio parameter according to the third voltage value and the fourth voltage value;

calculating a third ratio parameter according to the fourth voltage value and the fifth voltage value;

calculating to obtain the resistance value of the first resistive element according to the first ratio parameter, the second ratio parameter, the third ratio parameter and the resistance value of the first voltage dividing resistor;

calculating the resistance value of the second resistive element according to the resistance value of the first resistive element and the first ratio parameter;

and calculating the resistance value of the third resistive element according to the resistance value of the first resistive element and the second ratio parameter.

3. The detection circuit according to claim 1 or 2, wherein the control device is further configured to determine the environmental parameter value corresponding to the variable resistive component according to a resistance value of the variable resistive component;

wherein the environmental parameter comprises a temperature parameter.

4. The detection circuit according to claim 1 or 2, wherein,

The first, second and third resistive elements comprise any one or a combination of a thermistor, photoresistor, piezoresistor.

5. The detection circuit according to claim 1 or 2, characterized in that the detection circuit further comprises:

And the first end of the second voltage dividing resistor is connected with the second signal output end, and the second end of the second voltage dividing resistor is connected with the second end of the first resistive element.

6. A control method of a detection circuit, comprising:

Outputting a test signal to the variable resistive element through the signal output circuit;

Acquiring a voltage value of the variable resistive component through a sampling circuit;

The variable resistive component comprises:

a first resistive element;

a first signal output connected to a first end of the first resistive element;

The test signal comprises a high level signal and a floating input signal, and the specific steps of outputting the test signal to the variable resistance component through a signal output circuit comprise:

Controlling one of a first signal output end and a second signal output end to output the high-level signal, and controlling the other of the first signal output end and the second signal output end to output the floating input signal;

The sampling circuit includes:

A first sampling end connected to a first end of the first resistive element;

a second sampling end connected to a second end of the first resistive element;

The step of obtaining the voltage value of the variable resistive component through the sampling circuit specifically comprises the following steps:

Based on the first signal output end, outputting a floating input signal, and the second signal output end outputting a high-level signal, acquiring a first voltage value at a first end of the first resistive element through a first sampling end and acquiring a second voltage value at a second end of the first resistive element through a second sampling end;

Based on the first signal output end outputting a high-level signal and the second signal output end outputting a floating input signal, collecting a third voltage value at a first end of the first resistive element through the first sampling end, collecting a fourth voltage value at a second end of the first resistive element through the second sampling end, and collecting a fifth voltage value at a first end of the first voltage dividing resistor through the third sampling end;

7. The method according to claim 6, wherein the step of determining the resistance values of the first resistive element, the second resistive element, and the third resistive element, specifically comprises:

8. The control method of the detection circuit according to claim 6 or 7, characterized by further comprising:

Determining an environment parameter value corresponding to the variable resistance component according to the resistance value of the variable resistance component;

wherein the environmental parameter comprises a temperature parameter.

9. The method for controlling a detection circuit according to claim 6 or 7, wherein,

10. A cooking appliance, comprising:

a cooking chamber;

the detection circuit according to any one of claims 1 to 5;

A memory;

A processor, and a computer program stored on the memory and executable on the processor;

The computer program, when executed by the processor, implements a method of controlling a detection circuit as claimed in any one of claims 6 to 9.

11. The cooking appliance of claim 10, wherein the cooking appliance further comprises:

The signal output circuit, the sampling circuit and the control device in the detection circuit are arranged on the circuit board;

and the temperature probe is connected with the circuit board, and the variable resistance component in the detection circuit is arranged in the temperature probe.

12. The cooking appliance of claim 11, wherein the cooking appliance further comprises a handle,

The variable resistive component includes a first resistive element, a second resistive element, and a third resistive element;

Wherein the first, second and third resistive elements are thermistors.

13. A computer-readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements a method of controlling a detection circuit according to any one of claims 6 to 9.