Signal detection circuit, signal detection system and cooking equipment

Abstract

The invention discloses a signal detection circuit, a signal detection system and cooking equipment. Relates to the technical field of signal detection, and the signal detection circuit comprises a sampling circuit 101 which comprises a first resistor R1, a second resistor R2 and a third resistor R3 which are connected in series, the second resistor R2 is a temperature sensor arranged in target equipment, the third resistor R3 is connected with a switching device K in parallel, and the on-off state of the switching device K is determined by the equipment state of the target equipment; and the first chip 102 supplies power to the sampling circuit 101 and collects the voltage of a sampling point on a line between the first resistor R1 and the second resistor R2 to obtain a sampling signal value, and the sampling signal value is used for representing the temperature and the equipment state of the target equipment. By means of the electric pressure cooker, the problem that in the prior art, a thermistor in a temperature detection module arranged on a cooker cover of a split type electric pressure cooker can only sense a temperature signal and cannot sense an upper pressure signal, and the pressure state in the cooker is difficult to detect is solved.

Description

Technical Field

[0001] The present application relates to the technical field of signal detection, and in particular to a signal detection circuit, a signal detection system and a cooking device. Background Art

[0002] The electric pressure cooker has the function of cooking food quickly and is an indispensable cooking tool in the modern kitchen. Electric pressure cookers include combined electric pressure cookers and split electric pressure cookers. The lid of the split electric pressure cooker can be removed, which is convenient for cleaning and has a wide range of applications.

[0003] The split-type electric pressure cooker in the related art can detect the temperature signal through the temperature detection module on the lid of the electric pressure cooker, and transmit it to the control module of the main body of the electric pressure cooker by wireless transmission. The temperature detection module is provided with a thermistor, which can only sense the temperature signal but cannot sense the pressure signal of the cooking device. If the pressure signal of the cooking device is to be detected, the detection chip needs to be redesigned, and the chip design is difficult and costly.

[0004] Currently, no effective solution has been proposed to solve the problem that the thermistor in the temperature detection module provided on the lid of the split electric pressure cooker in the related art can only sense the temperature signal but cannot sense the pressure signal, making it difficult to detect the pressure state in the pot. Summary of the invention

[0005] The present application provides a signal detection circuit, a signal detection system and a cooking device to solve the problems in the related art.

[0006] According to one aspect of the present application, a signal detection circuit is provided. The signal detection circuit of the method includes: a sampling circuit, including a first resistor, a second resistor and a third resistor connected in series, the second resistor is a temperature sensor set inside the target device, and the third resistor is connected in parallel with a switch device, and the on-off state of the switch device is determined by the device state of the target device; a first chip supplies power to the sampling circuit through a first power port, and collects the voltage of a sampling point on the line between the first resistor and the second resistor through a signal line to obtain a sampling signal value. The problem that the thermistor in the temperature detection module set on the pot cover of the split-type electric pressure cooker in the related art can only sense the temperature signal, but cannot sense the upper pressure signal, and it is difficult to detect the pressure state in the pot is solved. The resistor connected in series with the temperature sensor in the sampling circuit is connected in parallel with a switch device, and the on-off state of the switch device is determined by the device state. The sampling signal value collected from the sampling point can simultaneously characterize the device temperature and the device state, thereby achieving the effect that the detection circuit simultaneously detects the temperature and pressure state in the pot of the electric pressure cooker.

[0007] Optionally, the resistance range of the second resistor is 0.1KΩ-100KΩ, and the resistance range of the third resistor is 10KΩ-100KΩ. By setting the resistance of the third resistor according to the characteristic that the resistance of the second resistor changes with temperature, the purpose of accurately determining the device state and temperature according to the sampling signal value can be achieved.

[0008] Optionally, a bias resistor is connected in series between the first resistor and the second resistor, the bias resistor has a resistance range of 0KΩ-30KΩ, and the first resistor has a resistance range of 2KΩ-30KΩ. The resistance value of the first resistor is set according to the resistance value of the bias resistor of the first chip, so that the setting of the sampling circuit can meet the working requirements of the first chip.

[0009] Optionally, the signal detection circuit also includes: a first wireless power supply circuit, including a first coupling coil connected in parallel at both ends of the second power port and the third power port of the first chip, and a first capacitor connected in parallel with the first coupling coil, wherein the first coupling coil is used to obtain electrical energy and charge the first capacitor, and the first capacitor is used to discharge the electrical energy to the second wireless power supply circuit; a second wireless power supply circuit, including a second capacitor connected in series between the fourth power port and the ground line of the first chip, and a fourth resistor connected in parallel with the second capacitor, wherein the first capacitor charges the second capacitor through the fourth resistor, and the second capacitor supplies power to the first chip through the fourth resistor. The signal detection circuit can be a wireless module, which is charged by wireless charging, so that the signal detection circuit can be suitable for signal detection of a split target device.

[0010] According to another aspect of the present application, a signal detection system is provided. The signal detection system includes: the above-mentioned signal detection circuit, which is used to be set on the target device, used to collect sampling signal values, and send the sampling signal values ​​to the signal processing circuit; the signal processing circuit, which communicates with the signal detection circuit wirelessly, is used to power the signal detection circuit, and is also used to receive the sampling signal value, determine the device state of the target device based on the relationship between the pre-stored preset sampling signal value and the preset device state, and determine the temperature of the target device based on the relationship between the pre-stored preset sampling signal value and the preset temperature value under different device states. In the sampling circuit of the signal detection circuit, a resistor connected in series with the temperature sensor is connected in parallel with a switch device, and the open and closed state of the switch device is determined by the device state. The sampling signal value collected from the sampling point can simultaneously represent the device temperature and the device state. The signal processing circuit determines the device state and the device temperature according to the pre-stored preset sampling signal value and the relationship data between the device state and the device temperature, thereby achieving the effect that the detection circuit simultaneously detects the temperature and pressure state in the pot of the electric pressure cooker.

[0011] Optionally, the signal processing circuit includes: a radio frequency gain circuit connected to the second chip, including a second coupling coil, used to control the oscillation of the second coupling coil to charge the signal detection circuit and receive the sampling signal; a detection circuit connected to the second chip, used to perform detection processing on the sampling signal and send the processed signal to the second chip; the second chip is used to determine the device state of the target device based on the relationship between the pre-stored preset sampling signal value and the preset device state, and determine the temperature of the target device based on the relationship between the pre-stored preset sampling signal value and the preset temperature value under different device states. Through the cooperation of the radio frequency gain circuit, the detection circuit and the second chip, the signal processing circuit supplies power to the signal detection circuit, obtains the sampling signal value detected by the signal detection circuit, and further determines the device temperature and device state based on the sampling signal value.

[0012] According to another aspect of the present application, a cooking device is provided. The cooking device comprises: the above-mentioned signal detection system; a pot body, and a pot cover arranged on the top of the pot body, the pot cover is used to seal the pot body, wherein the signal detection circuit in the signal detection system is arranged on the pot cover, and the signal processing circuit in the signal detection system is arranged on the pot body; a micro control unit, the micro control unit is connected in communication with the signal processing circuit, and is used to call the temperature and device status in the signal processing circuit, and control the operation of the pot body based on the temperature and device status. The sampling signal value collected by the signal detection circuit arranged on the pot cover can reflect the device temperature and device pressure status, and the signal processing circuit arranged on the pot body obtains the sampling signal value by wireless transmission, and processes it into the device temperature and device pressure status, thereby achieving the effect that the detection circuit simultaneously detects the temperature and pressure status in the pot of the electric pressure cooker, and improves the cooking quality and cooking efficiency of the cooking device.

[0013] Optionally, a stopper rod is provided on the pot cover, and the open / closed state of the stopper rod is used to determine the on / off state of the switch device. The on / off state of the switch device is associated with the open / closed state of the stopper rod in the cooking device, and the open / closed state of the stopper rod reflects the pressure state of the cooking device, so that the on / off state of the switch device reflects the pressure state of the cooking device.

[0014] Optionally, the anti-opening rod is connected to a trigger, the switch device is an induction switch, and the trigger is used to trigger the on and off of the induction switch. When the cooking device is in a non-pressurized state, the anti-opening rod drives the trigger away from the induction switch when it is opened, and the induction switch is in an open state if it cannot sense the trigger. When the cooking device is in a pressurized state, the anti-opening rod drives the trigger close to the induction switch when it is closed, and the induction switch is in a closed state if it senses the trigger. The pressure state in the pot can be accurately detected through the cooperation of the trigger and the induction switch.

[0015] Optionally, the trigger is a magnet, and the induction switch is a magnetic control switch. When the cooking device is in a non-pressurized state, the anti-opening rod drives the magnet away from the magnetic control switch when it is opened, and the magnetic control switch is in an open state if it cannot detect the magnet. When the cooking device is in a pressurized state, the anti-opening rod drives the magnet close to the magnetic control switch when it is closed, and the magnetic control switch is in a closed state if it detects the magnet. The pressure state in the pot can be accurately detected by the cooperation of the magnet and the magnetic control switch.

[0016] In the present application, the sampling circuit in the signal detection circuit includes a first resistor, a second resistor and a third resistor connected in series, the second resistor is a temperature sensor set inside the target device, and the third resistor is connected in parallel with a switch device, and the on-off state of the switch device is determined by the device state of the target device; the first chip in the signal detection circuit supplies power to the sampling circuit through the first power port, and collects the voltage of the sampling point on the line between the first resistor and the second resistor through the signal line to obtain the sampling signal value, which solves the problem that the thermistor in the temperature detection module set on the pot cover of the split electric pressure cooker in the related art can only sense the temperature signal, but cannot sense the upper pressure signal, and it is difficult to detect the pressure state in the pot. The resistor in series with the temperature sensor in the sampling circuit is connected in parallel with a switch device, and the on-off state of the switch device is determined by the device state. The sampling signal value collected from the sampling point can simultaneously characterize the device temperature and the device state, thereby achieving the effect that the detection circuit simultaneously detects the temperature and pressure state in the pot of the electric pressure cooker. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0018] Figure 1 is a schematic diagram of a signal detection circuit according to an embodiment of the present application;

[0019] Figure 2 is a schematic diagram of an optional signal detection circuit according to an embodiment of the present application;

[0020] Figure 3 is a schematic diagram of a signal detection system according to an embodiment of the present application;

[0021] Figure 4 is a schematic diagram of an optional radio frequency gain circuit according to an embodiment of the present application;

[0022] Figure 5 is a schematic diagram of an optional detection circuit according to an embodiment of the present application;

[0023] Figure 6 is a schematic diagram of an optional second chip according to an embodiment of the present application;

[0024] Figure 7 is a schematic diagram of a cooking device according to an embodiment of the present application;

[0025] Among them, 10, signal detection circuit; 11, signal processing circuit; 101, sampling circuit; 102, first chip; 103, first wireless power supply circuit; 104, second wireless power supply circuit; 21, pot body; 22, pot cover; 30, micro control unit; R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; REF, bias resistor; C1, first capacitor; C2, second capacitor; K, switching device; L1, first coupling coil; L2, second coupling coil. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] According to an embodiment of the present application, a signal detection circuit is provided.

[0030] Figure 1 is a schematic diagram of a signal detection circuit according to an embodiment of the present application. Figure 1 As shown, the signal detection circuit includes the following parts:

[0031] The sampling circuit 101 includes a first resistor R1, a second resistor R2 and a third resistor R3 connected in series. The second resistor R2 is a temperature sensor arranged inside the target device. The third resistor R3 is connected in parallel with a switch device K. The on / off state of the switch device K is determined by the device state of the target device.

[0032] It should be noted that the target device may be a cooking device, such as an electric pressure cooker, and the device state may be a non-pressurized state or a pressurized state. The non-pressurized state means that the pressure inside the pot is close to or equal to normal pressure, and the pressurized state means that the pressure inside the electric pressure cooker is higher than normal pressure. The on-off state of the switch device K is associated with the device state of the target device. The on-off state of the switch device K is different for different device states. For example, when the electric pressure cooker is in the non-pressurized state, the switch device K is in the open state; when the electric pressure cooker is in the pressurized state, the switch device K is in the closed state.

[0033] Among them, one end of the sampling circuit 101 and the first power port of the first chip 102 ( Figure 1 The other end of the sampling circuit 101 is grounded, and the first chip 102 supplies power to the sampling circuit 101. When the switch device K is in the open state, the first resistor R1, the second resistor R2 and the third resistor R3 divide the voltage. When the switch device K is in the closed state, the third resistor R3 is short-circuited, and the first resistor R1 and the second resistor R2 divide the voltage.

[0034] The first chip 102 supplies power to the sampling circuit 101 through the first power port, collects the voltage of the sampling point on the line between the first resistor R1 and the second resistor R2 through the signal line, and obtains the sampling signal value.

[0035] Among them, the signal line of the first chip 102 is connected from the pin VREFL to the sampling point, the voltage of the sampling point is the voltage to ground of the sampling point, the first resistor R1 can be connected to the first power port, and the third resistor R3 can be connected to the ground line. When the switch device K is in the open state, the first resistor R1, the second resistor R2 and the third resistor R3 divide the voltage, and the voltage of the sampling point is the total divided voltage value of the second resistor R2 and the third resistor R3. The sampling signal value is a digitized voltage value, which can be the total divided voltage value of the second resistor R2 and the third resistor R3, or the reverse value of the total divided voltage value of the second resistor R2 and the third resistor R3, that is, the divided voltage value of the first resistor R1. When the switch device K is in the closed state, the first resistor R1 and the second resistor R2 divide the voltage, and the voltage of the sampling point is the divided voltage value of the second resistor R2. The sampling signal value can be the divided voltage value of the second resistor R2, or the reverse value of the divided voltage value of the second resistor R2, that is, the divided voltage value of the first resistor R1.

[0036] The temperature sensor can be a thermistor. On the one hand, no matter the switch device K is in the open state or the closed state, the resistance and voltage divider value of the thermistor will change with the temperature inside the target device, the voltage value of the sampling point to the ground will change with the temperature, and the sampling signal value will change with the temperature. Therefore, the sampling signal value can be used to characterize the temperature of the target device. On the other hand, when the switch device K is in the open state and the closed state, the law of how the voltage divider value of the thermistor changes with the temperature is different, the law of how the voltage value of the sampling point to the ground changes with the temperature is different, and the law of how the sampling signal value changes with the temperature is also different. Therefore, the sampling signal value can be used to characterize the device state of the target device.

[0037] It should be noted that in the related art, there is a solution of setting two parallel detection circuits to measure the temperature and pressure state of the cooking device respectively. On the one hand, when the temperature or pressure state changes, the two detection signals change at the same time, which will cause crosstalk and affect the accuracy of temperature and pressure state detection. On the other hand, it is necessary to sample the sampling signals of the two signal detection points, and the two signals need to be processed separately in the chip to determine the temperature and pressure state of the cooking device. Two signal acquisition channels and signal processing procedures need to be designed in the chip. In the present application, a switch device K connected in parallel with the voltage divider resistor is set in the sampling circuit 101, and the sampling signal value collected can accurately characterize the device temperature and device state at the same time. Without changing the chip design of the sampling circuit 101, the device temperature and device state can be collected at a low cost.

[0038] The signal detection circuit provided in the embodiment of the present application includes a first resistor R1, a second resistor R2 and a third resistor R3 connected in series through a sampling circuit 101, wherein the second resistor R2 is a temperature sensor set inside the target device, and the third resistor R3 is connected in parallel with a switch device K, and the on-off state of the switch device K is determined by the device state of the target device; the first chip 102 supplies power to the sampling circuit 101 through a first power port, and collects the voltage of a sampling point on the line between the first resistor R1 and the second resistor R2 through a signal line to obtain a sampling signal value, thereby solving the problem that the thermistor in the temperature detection module set on the pot cover of the split-type electric pressure cooker in the related art can only sense the temperature signal, but cannot sense the upper pressure signal, and it is difficult to detect the pressure state in the pot. The resistor connected in series with the temperature sensor in the sampling circuit 101 is connected in parallel with a switch device, and the on-off state of the switch device is determined by the device state. The sampling signal value collected from the sampling point can simultaneously represent the device temperature and the device state, thereby achieving the effect that the detection circuit simultaneously detects the temperature and pressure state in the pot of the electric pressure cooker.

[0039] Optionally, in the signal detection circuit provided in the embodiment of the present application, the resistance range of the second resistor R2 is 0.1KΩ-100KΩ, and the resistance range of the third resistor R3 is 10KΩ-100KΩ.

[0040] The second resistor R2 may be an NTC (Negative Temperature Coefficient) thermistor, and the resistance range of the NTC thermistor may be 0.1 KΩ-100 KΩ, which can meet the requirements of detection accuracy in different temperature detection scenarios.

[0041] Exemplarily, the target device is an electric pressure cooker, and the resistance of the third resistor R3 is in the same order of magnitude as that of the second resistor R2 (for example, the resistance of the second resistor R2 is 50KΩ, and the resistance range of the third resistor R3 is 10KΩ-100KΩ). If the resistance of the third resistor R3 is relatively large, the temperature uncertainty section can be reduced when the reed switch fails due to short circuit. For example, the second resistor R2 is an NTC thermistor, and the resistance of the NTC thermistor is 100KΩ. If the resistance of the third resistor R3 is 30KΩ, the temperature uncertainty section can be controlled below 50°C. If the resistance of the third resistor R3 is 50KΩ, the temperature uncertainty section can be controlled below 40°C. In addition, the third resistor R3 should not be too large. When the third resistor R3 is too large, the voltage division of the first resistor R1 is too small, so that the resolution of the high temperature section data after the reed switch fails due to open circuit is too low.

[0042] Through this embodiment, the resistance value of the third resistor R3 is set according to the characteristic that the resistance value of the second resistor R2 changes with temperature, so that the purpose of accurately determining the device state and temperature according to the sampling signal value can be achieved.

[0043] Optionally, in the signal detection circuit provided in the embodiment of the present application, a bias resistor REF is connected in series between the first resistor R1 and the second resistor R2, the resistance range of the bias resistor REF is 0KΩ-30KΩ, and the resistance range of the first resistor R1 is 2KΩ-30KΩ.

[0044] The sampling circuit 101 may also be connected in series with a resistor other than the first resistor R1, the second resistor R2, and the third resistor R3. Considering the half bias characteristic of the first chip 102 (meaning that the voltage applied by the first chip 102 or its internal components is half of its normal operating voltage), the first resistor R1 and the second resistor R2 are connected in series with a bias resistor REF, and the resistance value of the first resistor R1 needs to be close to the resistance value of the bias resistor REF. For example, if the resistance value of the bias resistor REF is 21K, the second resistor R2 may be 20KΩ. In addition, the first resistor R1, the second resistor R2 and the third resistor R3 are voltage-divided, and the second resistor R2 and the third resistor R3 need to match the resistance of the first resistor R1. The resistance values ​​of the three can be set within the same order of magnitude (for example, the resistance value of the first resistor R1 is 1KΩ, and the resistance value range of the second resistor R2 and the third resistor R3 is 1KΩ-10KΩ). When the resistance values ​​of the three are within the same order of magnitude, the resistance value of the first resistor R1 should not be too large or too small. When the resistance value of the first resistor R1 is too small, inaccurate measurement in the high temperature section will result. When the resistance value of the first resistor R1 is too small, inaccurate measurement in the low temperature section will result.

[0045] Through this embodiment, the resistance value of the first resistor R1 is set according to the resistance value of the bias resistor REF of the first chip 102 , so that the setting of the sampling circuit 101 can meet the working requirements of the first chip 102 .

[0046] The signal detection circuit can be a wireless module, which is charged by wireless charging. Optionally, in the signal detection circuit provided in the embodiment of the present application, the signal detection circuit also includes: a first wireless power supply circuit 103, including a first coupling coil L1 connected in parallel at both ends of the second power port and the third power port of the first chip 102, and a first capacitor C1 connected in parallel with the first coupling coil L1, wherein the first coupling coil L1 is used to obtain electric energy and charge the first capacitor C1, and the first capacitor C1 is used to discharge the electric energy to the second wireless power supply circuit 104; the second wireless power supply circuit 104 includes a second capacitor C2 connected in series between the fourth power port and the ground line of the first chip 102, and a fourth resistor R4 connected in parallel with the second capacitor C2, wherein the first capacitor C1 charges the second capacitor C2 through the fourth resistor R4, and the second capacitor C2 supplies power to the first chip 102 through the fourth resistor R4.

[0047] Figure 2 is a schematic diagram of an optional signal detection circuit according to an embodiment of the present application, such as Figure 2As shown, the second power port of the first chip 102 is an interface indicated by the RF1 pin, the third power port of the first chip 102 is an interface indicated by the RF2 pin, and the first coupling coil L1 can be a radio frequency coil. When the signal processing circuit provided with a power supply generates an electromagnetic field through the radio frequency coil, the first coupling coil L1 generates a current through the electromagnetic field and charges the first capacitor C1. The radio frequency coil of the signal processing circuit provided with a power supply oscillates continuously, and the first capacitor C1 intermittently charges energy to the second capacitor C2 through the circuit inside the first chip 102. When the first capacitor C1 charges the second capacitor C2, the fourth resistor R4 acts as a charging resistor. When the first capacitor C1 stops charging the second capacitor C2, the second capacitor C2 supplies power to the first chip 102, and the fourth resistor R4 acts as a discharge resistor. The first chip 102 is powered on when receiving electric energy and supplies power to the sampling circuit 101.

[0048] In this embodiment, the signal detection circuit may be a wireless module, which is charged by wireless charging, so that the signal detection circuit can be suitable for signal detection of a split target device.

[0049] The embodiment of the present application also provides a signal detection system.

[0050] Figure 3 Schematic diagram of a signal detection system according to an embodiment of the present application. Figure 3 As shown, the device comprises:

[0051] The signal detection circuit 10 in any of the above embodiments is configured to be disposed on a target device, to collect sampled signal values, and to send the sampled signal values ​​to the signal processing circuit 11 .

[0052] It should be noted that the target device can be a cooking device, for example, an electric pressure cooker. The signal detection circuit 10 is set on the electric pressure cooker to sample the sampling signal value that represents the temperature and device status of the electric pressure cooker. The signal detection circuit 10 can be a wireless module that sends the sampling signal value to the signal processing circuit 11 via wireless transmission.

[0053] The signal processing circuit 11 wirelessly communicates with the signal detection circuit 10, is used to power the signal detection circuit 10, and is also used to receive the sampling signal value, determine the device state of the target device based on the relationship between the pre-stored preset sampling signal value and the preset device state, and determine the temperature of the target device based on the relationship between the pre-stored preset sampling signal value and the preset temperature value under different device states.

[0054] On the one hand, the signal processing circuit 11 generates an electromagnetic field through the second coupling coil L2 and powers the signal detection circuit 10 by electromagnetic induction. On the other hand, the second coupling coil L2 of the signal processing circuit 11 and the coupling coil L1 of the signal detection circuit 10 communicate through an agreed preset resonant frequency. The coupling coil L1 of the signal detection circuit 10 sends the sampling signal value according to the preset resonant frequency, and the signal processing circuit 11 receives the sampling signal value sent by the signal detection circuit 10 according to the preset resonant frequency.

[0055] It should be noted that, since the sampled signal value represents the temperature and device state of the target device, the signal processing circuit 11 can determine the temperature and device state of the target device based on the sampled signal value.

[0056] The signal processing circuit 11 pre-stores first relationship data between a preset sampling signal value and a preset device state. For example, the first relationship data may be: when the preset sampling signal value is less than a preset signal threshold, it corresponds to a first device state; when the preset sampling signal value is greater than or equal to the preset signal threshold, it corresponds to a second device state. Therefore, the device state can be determined based on the acquired sampling signal value and the pre-stored first relationship data.

[0057] The signal processing circuit 11 also pre-stores second relationship data between preset sampling signal values ​​and preset temperature values ​​under different device states. The second relationship data may include a first curve and a second curve. The first curve represents the relationship between the preset sampling signal value and the preset temperature value under the first device state, and the second curve represents the relationship between the preset sampling signal value and the preset temperature value under the second device state. The device state can be determined based on the acquired sampling signal value and the pre-stored first relationship data, and then the temperature value corresponding to the sampling signal value is queried on the curve corresponding to the corresponding device state, which is the temperature of the target device.

[0058] In an optional embodiment, the target device is a cooking device, the first device state is a non-pressurized state, and the second device state is a pressurized state. When the cooking device is in the non-pressurized state, the switch device K in the signal detection circuit 10 is disconnected, the first resistor R1, the second resistor R2, and the third resistor R3 participate in voltage division, and the first curve is the reverse value of the voltage value of the second resistor R2 and the third resistor R3 to the ground, that is, the voltage division value of the first resistor R1, and the first curve is a relationship curve between the voltage division value of the first resistor R1 and the temperature of the cooking device. When the cooking device is in the pressurized state, the switch device K in the signal detection circuit 10 is closed, the first resistor R1 and the second resistor R2 participate in voltage division, the first curve is the reverse value of the voltage value of the second resistor R2 to the ground, that is, the voltage division value of the first resistor R1, and the second curve is a relationship curve between the voltage division value of the first resistor R1 and the temperature of the cooking device. The preset signal threshold is set to the sampling signal value corresponding to any temperature value greater than the boiling point in the first curve, for example, it can be the sampling signal value corresponding to any temperature value between 130°C and 150°C, so as to avoid inaccurate temperature measurement when the switch device K fails.

[0059] The signal detection system provided in the embodiment of the present application is used to be set on the target device through the signal detection circuit 10 in any of the above embodiments, and is used to collect the sampled signal value and send the sampled signal value to the signal processing circuit 11; the signal processing circuit 11 wirelessly communicates with the signal detection circuit 10, is used to power the signal detection circuit 10, and is also used to receive the sampled signal value, determine the device state of the target device based on the relationship between the pre-stored preset sampled signal value and the preset device state, and determine the temperature of the target device based on the relationship between the pre-stored preset sampled signal value under different device states and the preset temperature value, thereby solving the problem of the split voltage The thermistor in the temperature detection module arranged on the lid of the pressure cooker can only sense the temperature signal but cannot sense the pressure signal, making it difficult to detect the pressure state in the pot. The resistor connected in series with the temperature sensor in the sampling circuit 101 in the signal detection circuit 10 is connected in parallel with a switch device, and the on and off state of the switch device is determined by the device state. The sampling signal value collected from the sampling point can simultaneously characterize the device temperature and the device state. The signal processing circuit 11 determines the device state and the device temperature according to the relationship data between the pre-stored preset sampling signal value and the device state and the device temperature, thereby achieving the effect that the detection circuit simultaneously detects the temperature and pressure state in the pot of the electric pressure cooker.

[0060] Optionally, in the signal detection system provided in the embodiment of the present application, the signal processing circuit 11 includes: a radio frequency gain circuit, connected to the second chip, including a second coupling coil L2, used to control the oscillation of the second coupling coil L2 to charge the signal detection circuit 10 and receive a sampling signal; a detection circuit, connected to the second chip, used to perform detection processing on the sampling signal and send the processed signal to the second chip; the second chip is used to determine the device state of the target device based on the relationship between the pre-stored preset sampling signal value and the preset device state, and determine the temperature of the target device based on the relationship between the pre-stored preset sampling signal value and the preset temperature value under different device states.

[0061] Figure 4 is a schematic diagram of an optional RF gain circuit according to an embodiment of the present application, such as Figure 4 As shown, the second coupling coil L2 is composed of a coil L21 and a coil L22, and the coil L21 and the coil L22 are used to transmit an oscillation signal, and transfer energy to the first coupling coil L1 in the sampling circuit 101 through the coil RF. The coil L21 and the coil L22 are also used to receive the sampling signal value transmitted by the first coupling coil L1, and the Signal terminal is used to connect to the detection circuit, so as to transfer the sampling signal value to the detection circuit.

[0062] Figure 5 is a schematic diagram of an optional detection circuit according to an embodiment of the present application, such as Figure 5 As shown, the Signal terminal of the detection circuit is used to connect to the RF gain circuit, receive the sampled signal value, perform detection processing on the sampled signal value, and then send it to the second chip through the RFR terminal.

[0063] Figure 6 is a schematic diagram of an optional second chip according to an embodiment of the present application, such as Figure 6 As shown, the RFR pin of the second chip is connected to the RFR terminal of the detection circuit to receive the sampled signal value after the detection processing; the RFP pin and the RFN pin of the second chip are respectively connected to the RFP terminal and the RFN terminal of the RF gain circuit to control the RF gain circuit; the LED pin of the second chip is connected to the LED indicator light, the CN1 pin is used to debug the chip, the IDA pin is used to implement the burning program, the ICK pin is used to input and output signals, and the capacitor C4 and the capacitor C5 are the filter capacitors of the second chip.

[0064] Through the cooperation of the RF gain circuit, the detection circuit and the second chip, the signal processing circuit 11 supplies power to the signal detection circuit 10, obtains the sampling signal value detected by the signal detection circuit 10, and further determines the device temperature and device status based on the sampling signal value.

[0065] The embodiment of the present application also provides a cooking device.

[0066] Figure 7 Schematic diagram of a cooking device according to an embodiment of the present application. Figure 7 As shown, the cooking device comprises:

[0067] The signal detection system according to any one of the above embodiments.

[0068] A pot body 21, and a pot cover 22 arranged on the top of the pot body 21, the pot cover 22 is used to seal the pot body 21, wherein the signal detection circuit 10 in the signal detection system is arranged on the pot cover 22, and the signal processing circuit 11 in the signal detection system is arranged on the pot body 21.

[0069] It should be noted that the cooking device in this embodiment can be a split electric pressure cooker. The pot body 21 and the pot lid 22 are detachable, and the signal detection circuit 10 is arranged on the pot lid 22. In order to make the pot lid 22 light, the signal detection circuit 10 does not have a power supply or a charger. The signal detection circuit 10 is a wireless module. When the pot lid is closed, the pot body 21 and the pot lid 22 are in contact, and the signal detection circuit 10 is within the sensing range of the signal processing circuit 11. The signal processing circuit 11 powers the signal detection circuit 10 by wireless charging. The signal detection circuit 10 transmits the detected sampling signal value to the signal processing circuit 11 by wireless transmission, and the signal processing circuit 11 processes the sampling signal value into temperature and device status.

[0070] The micro control unit 30 is in communication with the signal processing circuit 11 and is used to call the temperature and device status in the signal processing circuit 11 and control the operation of the pot body 21 based on the temperature and device status.

[0071] Specifically, during the operation of the cooking device, the microcontroller unit 30 continuously calls the temperature and device status collected by the signal processing circuit 11 to obtain the real-time temperature and real-time pressure status inside the cooking device. On the one hand, it determines which stage of the cooking program to enter based on the temperature. On the other hand, when the pressure state in the pot jumps to the unpressurized state during the exhaust stage, a lid opening signal can be output to solve the problem of long waiting time for users to exhaust. On the other hand, when the pressure state in the pot jumps to the unpressurized state during the exhaust stage, the corresponding temperature is the boiling point, and the boiling point can be accurately detected, so that the cooking temperature can be controlled according to the accurate boiling point when cooking porridge or soup, ensuring sufficient cooking while avoiding overflowing the pot.

[0072] The cooking device provided by the embodiment of the present application comprises a signal detection system in any of the above embodiments; a pot body 21, and a pot cover 22 arranged on the top of the pot body 21, the pot cover 22 is used to seal the pot body 21, wherein the signal detection circuit 10 in the signal detection system is arranged on the pot cover 22, and the signal processing circuit 11 in the signal detection system is arranged on the pot body 21; and a micro control unit 30, the micro control unit 30 is connected in communication with the signal processing circuit 11, and is used to call the temperature and device status in the signal processing circuit 11, and control the operation of the pot body 21 based on the temperature and device status. The problem that the thermistor in the temperature detection module arranged on the pot cover of the split electric pressure cooker in the related art can only sense the temperature signal, but cannot sense the upper pressure signal, and it is difficult to detect the pressure state in the pot is solved, the sampling signal value collected by the signal detection circuit 10 arranged on the pot cover 22 can reflect the device temperature and the device pressure state, and the signal processing circuit 11 arranged on the pot body 21 obtains the sampling signal value by wireless transmission, and processes it into the device temperature and the device pressure state, thereby achieving the effect of the detection circuit simultaneously detecting the temperature and the pressure state in the pot of the electric pressure cooker, and improving the cooking quality and cooking efficiency of the cooking device.

[0073] Optionally, in the cooking device provided in the embodiment of the present application, a stopper rod is provided on the pot cover 22, and the open and closed state of the stopper rod is used to determine the on and off state of the switch device K.

[0074] It should be noted that the anti-opening rod is located at the edge of the pot cover 22 of the electric pressure cooker. When the pressure inside the electric pressure cooker rises to the upper pressure state, the anti-opening rod will be pushed to the closed position by the internal pressure to lock the pot cover 22 to prevent accidental opening when the pressure is too high. When the anti-opening rod is opened, the pot is in a non-pressurized state, and the switch device K can be in an open state. When the anti-opening rod is closed, the pot is in an upper pressure state, and the switch device K can be in a closed state, thereby realizing the association between the on-off state of the switch device K and the on-off state of the anti-opening rod.

[0075] Through this embodiment, the on-off state of the switch device K is associated with the open-closed state of the anti-opening rod in the cooking device. The open-closed state of the anti-opening rod reflects the pressure state of the cooking device, so that the on-off state of the switch device K reflects the pressure state of the cooking device.

[0076] Optionally, in the cooking device provided in the embodiment of the present application, the stop rod is connected to a trigger member, the switch device K is an induction switch, and the trigger member is used to trigger the on and off of the induction switch.

[0077] Specifically, when the cooking device is in a non-pressurized state, the anti-opening rod drives the trigger member away from the sensing switch when it is opened, and the sensing switch is in an open state if it cannot sense the trigger member. When the cooking device is in a pressurized state, the anti-opening rod drives the trigger member close to the sensing switch when it is closed, and the sensing switch is in a closed state if it senses the trigger member. The pressure state in the pot can be accurately detected through the cooperation of the trigger member and the sensing switch.

[0078] Optionally, in the cooking device provided in the embodiment of the present application, the trigger member is a magnet and the induction switch is a magnetically controlled switch.

[0079] Specifically, the cooking device can be an electric pressure cooker, and the magnetically controlled switch can be a reed switch, a Hall element, etc. For example, the magnetically controlled switch is a reed switch, and the pot is in a non-pressurized state. When the anti-opening rod is opened, it drives the magnet away from the reed switch. If the reed switch cannot detect the magnet, it is in a disconnected state. When the pot is in a pressurized state, when the anti-opening rod is closed, it drives the magnet close to the reed switch. If the reed switch detects the magnet, it is in a closed state. The pressure state in the pot can be accurately detected through the cooperation of the magnet and the reed switch.

[0080] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0081] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A signal detection circuit, characterized in that: include: A sampling circuit (101) comprises a first resistor (R1), a second resistor (R2) and a third resistor (R3) connected in series, wherein the second resistor (R2) is a temperature sensor arranged inside a target device, and the third resistor (R3) is connected in parallel with a switch device (K), wherein the on / off state of the switch device (K) is determined by the device state of the target device; The first chip (102) supplies power to the sampling circuit (101) through a first power port, collects the voltage of a sampling point on the line between the first resistor (R1) and the second resistor (R2) through a signal line, and obtains a sampling signal value.

2. The signal detection circuit according to claim 1, characterized in that: The resistance value range of the second resistor (R2) is 0.1KΩ-100KΩ, and the resistance value range of the third resistor (R3) is 10KΩ-100KΩ.

3. The signal detection circuit according to claim 2, characterized in that: A bias resistor (REF) is connected in series between the first resistor (R1) and the second resistor (R2), the resistance range of the bias resistor (REF) is 0KΩ-30KΩ, and the resistance range of the first resistor (R1) is 2KΩ-30KΩ.

4. The signal detection circuit according to claim 1, characterized in that: The signal detection circuit also includes: A first wireless power supply circuit (103), comprising a first coupling coil (L1) connected in parallel to both ends of a second power port and a third power port of the first chip (102), and a first capacitor (C1) connected in parallel to the first coupling coil (L1), wherein the first coupling coil (L1) is used to obtain electric energy and charge the first capacitor (C1), and the first capacitor (C1) is used to discharge the electric energy to a second wireless power supply circuit (104); The second wireless power supply circuit (104) comprises a second capacitor (C2) connected in series between a fourth power port of the first chip (102) and a ground line, and a fourth resistor (R4) connected in parallel with the second capacitor (C2), wherein the first capacitor (C1) charges the second capacitor (C2) through the fourth resistor (R4), and the second capacitor (C2) supplies power to the first chip (102) through the fourth resistor (R4).

5. A signal detection system, characterized in that: include: The signal detection circuit (10) according to any one of claims 1 to 4, which is arranged on a target device, is used to collect sampled signal values, and sends the sampled signal values ​​to a signal processing circuit (11); The signal processing circuit (11) is in wireless communication with the signal detection circuit (10) and is used to power the signal detection circuit (10). It is also used to receive the sampling signal value, determine the device state of the target device based on the relationship between the pre-stored preset sampling signal value and the preset device state, and determine the temperature of the target device based on the relationship between the pre-stored preset sampling signal value and the preset temperature value under different device states.

6. The signal detection system according to claim 5, characterized in that: The signal processing circuit (11) comprises: A radio frequency gain circuit, connected to the second chip, comprising a second coupling coil (L2), used to control the oscillation of the second coupling coil (L2) to charge the signal detection circuit (10) and receive the sampling signal; A detection circuit, connected to the second chip, for performing detection processing on the sampled signal and sending the processed signal to the second chip; The second chip is used to determine the device state of the target device based on the relationship between the pre-stored preset sampling signal value and the preset device state, and to determine the temperature of the target device based on the relationship between the pre-stored preset sampling signal value and the preset temperature value under different device states.

7. A cooking device, characterized in that: include: The signal detection system according to any one of claims 5 to 6; A pot body (21), and a pot cover (22) arranged on the top of the pot body (21), the pot cover (22) being used to seal the pot body (21), wherein the signal detection circuit (10) in the signal detection system is arranged on the pot cover (22), and the signal processing circuit (11) in the signal detection system is arranged on the pot body (21); A micro control unit (30) is connected to the signal processing circuit (11) for communicating with the signal processing circuit (11) and for calling the temperature and device status in the signal processing circuit (11) to control the operation of the pot body (21) based on the temperature and the device status.

8. The cooking device according to claim 7, characterized in that The pot cover (22) is provided with a stopper rod, and the open and closed state of the stopper rod is used to determine the on and off state of the switch device (K).

9. The cooking device according to claim 8, characterized in that The anti-opening rod is connected to a triggering member, the switch device (K) is an induction switch, and the triggering member is used to trigger the on and off of the induction switch.

10. The cooking device according to claim 9, characterized in that The triggering member is a magnet, and the induction switch is a magnetically controlled switch.

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