Temperature detection device for multifunctional cooking integrated machine pot

Abstract

This invention relates to a multi-functional cooking appliance, and more particularly to a temperature detection device for the cookware in the multi-functional cooking appliance. The device includes three temperature sensors: an in-pot sensor mounted on the lid to detect the temperature of the gas inside the pot, a bottom sensor mounted on the bottom of the pot to detect the temperature of the bottom surface, and a heating plate sensor mounted on the heating plate to detect the surface temperature of the heating plate. After the cookware is started, the device collects the in-pot temperature, bottom temperature, and heating plate temperature detected by the three sensors. Based on the magnitude of at least two of the three temperature values ​​and their trends over time, the device determines whether the cookware is in a state of dry burning without a pot, dry burning with a pot, accidental burning dry, or the lid being opened midway. The determination is then sent to the main control center of the cookware, which in turn issues a stop-work command to the heating plate. This effectively protects the cookware components, enables automatic pot detection, and significantly improves the user experience.

Description

Technical Field

[0001] This invention relates to a multi-functional cooking appliance, and more particularly to a temperature detection device for use in the cookware of the multi-functional cooking appliance. Background Technology

[0002] Cooking all-in-one machines are favored by many consumers due to their powerful functions and high level of intelligence. However, when the cookware in these machines malfunctions during cooking (such as: dry burning without a pot (cooking without the pot being placed in the cookware), dry burning with a pot (cooking with the pot in place but without any food inside), accidental burning dry (the food inside the pot is burned dry due to a malfunction in the main control center), or accidentally opening the lid during cooking), the cookware is usually damaged because these machines lack safety alarms or circuits that trigger the shut-off of the heating plate. Even if safety alarms or circuits that trigger the shut-off of the heating plate are included, the complex structure, numerous components, and corresponding sensors result in high production costs. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a temperature detection device for a multi-functional cooking appliance that contains multiple temperature sensors working together to effectively prevent the cooker from drying out during cooking, whether the cooker is dry without a pot, has a pot, is accidentally boiled dry, or has its lid opened midway.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0005] A temperature detection device is provided for a multi-functional cooking appliance, characterized by comprising three temperature sensors: an in-pot sensor mounted on the lid to detect the temperature of the gas inside the pot, a bottom sensor mounted on the bottom of the pot to detect the temperature of the bottom surface, and a heating plate sensor mounted on the heating plate to detect the surface temperature of the heating plate. After the cooking appliance is started, the device collects the in-pot temperature, bottom temperature, and heating plate temperature detected by the three sensors. Based on the magnitude of at least two of the three temperature values ​​and their changing trends over time, the device determines whether the cooking appliance is in a state of dry burning without a pot, dry burning with a pot, accidental burning dry, or the lid being opened midway. The determination is then sent to the main control center of the cooking appliance, which in turn issues a stop-work command to the heating plate.

[0006] Furthermore, after the heating plate has been turned on for a short period of time, if the temperature inside the pot remains higher than the temperature at the bottom of the pot over time, it is determined that the pot is in an unloaded state of dry burning.

[0007] Furthermore, after the heating plate has been working for a short period of time, when the temperature change of the pot bottom and the heating plate per unit time tends to be the same and the temperature inside the pot is lower than the temperature of the pot bottom, it is determined that the pot is dry-burning.

[0008] Furthermore, during the normal operation of the heating plate, if the temperature inside the pot suddenly drops from a constant range value within 10 to 30 seconds, while the temperature of the bottom of the pot and the temperature of the heating plate are still rising, it is considered as an accidental burn-out or the pot lid being opened midway.

[0009] Furthermore, during the normal operation of the heating plate, when the temperature inside the pot suddenly changes from rising to falling, it is considered that the pot lid has been opened midway.

[0010] Furthermore, when the temperature of the bottom of the pot reaches the working temperature set by the cooking program, the main control center of the cookware switches the working mode of the heating plate to intermittent working mode.

[0011] Furthermore, the in-pot sensor, the bottom-pot sensor, and the heating plate sensor are all thermistors.

[0012] Furthermore, the heating plate has a central through hole in the center, and an aluminum cover that can move up and down elastically is installed in the central through hole. There is a gap between the aluminum cover and the inner wall of the central through hole. The bottom sensor is installed in the aluminum cover. When the pot is placed in the cooking pot, the aluminum cover moves downward so that the bottom surface of the pot comes into contact with the upper surface of the heating plate, and at the same time the bottom sensor comes into contact with the lower surface of the aluminum cover.

[0013] Compared with the prior art, the temperature detection device of the present invention can monitor the temperature in real time during the cooking process of the pot, and can control the working state of the heating plate through the coordinated work of multiple temperature sensors. It can effectively prevent abnormal working conditions such as dry burning without pot or dry burning of the pot body during cooking, effectively protect the pot components, realize automatic detection of the pot body, and effectively improve the user experience and sense of security. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the integrated machine frame and cooking pot according to an embodiment of the present invention;

[0015] Figure 2 This is a cross-sectional view of the cookware of this invention without the pot body inside;

[0016] Figure 3 This is a cross-sectional view of the pot body placed inside the cookware according to an embodiment of the present invention;

[0017] Figure 4 yes Figure 2 Enlarged view of point A in the middle;

[0018] Figure 5 yes Figure 3 Enlarged view at point B in the middle;

[0019] Figure 6 yes Figure 3 Enlarged view at point C;

[0020] Figure 7 This is one of the exploded views of the bottom portion structure of the pot according to an embodiment of the present invention;

[0021] Figure 8 This is one of the exploded views of the bottom portion structure of the pot according to an embodiment of the present invention;

[0022] The attached figures are labeled as follows:

[0023] All-in-one machine 100, cooking vessel 1, outer shell 11, inner shell 12, pot body 13, base 14, pot lid 2, pot internal sensor 21, heating plate 3, heating plate sensor 31, aluminum cover 32, baffle plate 320, outer spring 33, pot bottom detection device 4, pot bottom sensor 41, probe 410, sensor protective sleeve 42, sensor base 43, inner spring 44, driving gear 51, driven gear 52, sleeve 53, magnetic ring mounting position 530, bearing 54, fixing part 55, driven gear receiving position 550, mounting bracket 6, motor mounting hole 61, driving gear mounting position 62, driven gear mounting position 63, sleeve mounting hole 64, connecting bracket 7, lower limit part 71, upper limit part 72, magnetic ring 8, motor 9, output shaft 91; Detailed Implementation

[0024] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0025] Combination Figures 1 to 8 As shown, the temperature detection device of the present invention for the pot set on the multi-functional cooking appliance can realize real-time monitoring of the temperature inside the pot, the bottom of the pot and the heating plate 3 during the cooking process of the pot 1, effectively preventing abnormal working conditions such as dry burning inside the pot 1 and dry burning of the pot body 13 during the cooking process, effectively protecting the components of the pot 1, realizing automatic detection of the pot body 13 by the pot 1 and effectively improving the user experience.

[0026] like Figure 1 As shown, the frame of the multi-functional cooking appliance 100 can be integrated with various cooking devices with different cooking functions (only the pot 1 and its related components are shown in the figure). The pot 1 is one of the cooking devices. The frame of the appliance 100 includes a top plate, a three-dimensional frame and a bottom plate. The top plate is fixed to the upper end of the three-dimensional frame by a quick snap-fit ​​method, and the bottom plate is fixed to the bottom of the three-dimensional frame. A recess is provided on the top plate in the area where the pot 1 is located, and a central through hole is provided in the recess.

[0027] The shell of the cookware 1 is embedded in the central through hole and fixedly connected to the frame of the integrated machine 100. The pot body 13 of the cookware 1 is placed inside the shell. The cookware 1 includes a lid 2, an outer shell 11, an inner shell 12, a pot body 13, a heating plate 3, a temperature detection device, and a motor 9 and a transmission device for driving the magnetic stirring rod inside the pot to rotate.

[0028] The main function of the cooking pot 1 is to cook, stew, and simmer ingredients, such as cooking rice, making soup, making sweet soup, stewing chicken, and stewing pork ribs.

[0029] Combination Figures 1 to 6 As shown, the pot 1 is equipped with a temperature detection device, which mainly consists of an in-pot sensor 21, a bottom-pot sensor 41, and a heating plate sensor 31.

[0030] I. Installation of the in-pot sensor 21, the bottom-pot sensor 41, and the heating plate sensor 31

[0031] like Figure 1 As shown, the back of the substrate of the pot lid 2 is provided with a mounting hole for the pot inside sensor 21. The pot inside sensor 21 can be fixed in the mounting hole by means of adhesive, snap-fit, threaded connection, etc. In this embodiment, in order to facilitate installation, the pot inside sensor 21 used is a threaded hexagonal NTC thermistor with high precision, stable performance and fast response speed, which can be fixed to the pot lid substrate by threaded connection.

[0032] The probe 410 of the in-pot sensor 21 passes through the substrate and through the in-pot sensor through hole opened at the corresponding position on the lid 2. When the lid 2 is closed with the cookware 1, the in-pot sensor 21 is located at the top inside the pot body 13 of the cookware 1. During the operation of the cookware 1, the temperature of the gas inside the pot body 13 can be detected in real time and fed back to the main control center of the integrated machine 100, thereby participating in the control of the heating or cooling operation of the cookware 1.

[0033] The specific technical solution for the installation method of the in-pot sensor 21 can be referred to the patent applied for by the applicant on February 19, 2021, entitled "Pot lid for a cooker set on a multi-functional cooking appliance", application number: 202120379557.6, authorization announcement number: CN215383164U; see paragraphs

[0034] -

[0036] in the specification, which describe the specific method of installing the temperature control sensor on the pot lid 2. The temperature control sensor is the in-pot sensor 21 mentioned in this invention.

[0034] Combination Figure 2 and Figure 3As shown, the outer shell 11 and the inner shell 12 are fixedly connected to each other by a base 14. The lower surface of the base 14 is fixedly connected to the inner bottom surface of the outer shell 11, and its upper surface is fixedly connected to the outer bottom surface of the inner shell 12. A cavity is formed between the outer bottom surface of the inner shell 12, the base 14, and the inner bottom surface of the outer shell 11. The pot bottom detection device 4, the motor 9, and the transmission device are installed and fixedly connected in this cavity. The pot bottom detection device 4 consists of a pot bottom sensor 41, a sensor protective sleeve 42, a sensor base 43, and an inner spring 44 from top to bottom. The transmission device consists of a driving gear 51, a driven gear 52, a sleeve 53, and a bearing 54.

[0035] Combination Figure 3 and Figure 6 As shown, the inner bottom surface of the inner shell 12 is provided with screw holes for mounting the heating plate 3. The heating plate 3 is fixed to the screw holes by screws, thus fixing the heating plate 3 to the inner bottom surface of the inner shell 12. For easy installation, the heating plate sensor 31 used in this embodiment is a ring-shaped thermistor, which can be sleeved on the outside of the screw and fixed to the heating plate 3 and the inner shell 12 by the screw. The heating plate sensor 31 is used to detect the temperature of the heating plate 3. If the temperature of the heating plate 3 exceeds the safety value, the operation of the heating plate 3 will be turned off to protect the surrounding components of the heating plate 3 and prevent the components from being damaged or having their lifespan shortened due to overheating. At the same time, during the operation of the cooker 1, the temperature of the heating plate 3 can be detected in real time and fed back to the main control center of the integrated machine 100, thereby participating in the control of the heating operation of the cooker 1.

[0036] Combination Figure 4 and Figure 5 As shown, a through hole is provided in the center of both the heating plate 3 and the inner shell 12. An aluminum cover 32 that can move up and down elastically is provided in the central through hole of the heating plate 3. A gap is left between the aluminum cover 32 and the inner wall of the central through hole. This gap can effectively prevent the heating plate 3 from transferring heat to the aluminum cover 32 through contact connection, thereby affecting the temperature measurement accuracy of the pot bottom temperature sensor that will contact the aluminum cover 32.

[0037] Combination Figure 4 , Figure 7 and Figure 8As shown, a connecting frame 7 is fixed to the outer bottom surface of the inner shell 12. The connecting frame 7 has a lower limit member 71 that restricts the downward movement of the aluminum cover 32 and an upper limit member 72 that restricts the upward movement of the aluminum cover 32. The aluminum cover 32 is "cake-shaped" and has an outer spring 33 inside. The top end of the outer spring 33 abuts against the inner wall of the aluminum cover 32, and the bottom end abuts against the lower limit member 71. A baffle 320 extends from the outer wall of the aluminum cover 32, and the upper limit member 72 can be hooked onto the baffle 320. The vertical movement of the aluminum cover 32 is between the lower limit member 71 and the upper limit member 72. When the pot body 13 is not placed in the cookware 1, and the outer spring 33 is in its normally extended state, the upper part of the aluminum cover 32 passes through the central through hole, and its top surface is positioned above the heating plate 3. When the pot body 13 is placed in the cookware 1, the aluminum cover 32 compresses the spring and moves downward, and the top surface of the aluminum cover 32 always contacts the bottom surface of the pot.

[0038] Installation, connection, and driving relationship between motor 9 and transmission components:

[0039] Combination Figures 4 to 8 As shown, a mounting bracket 6 is fixedly attached to the lower surface of the connecting bracket 7. The mounting bracket 6 has a motor mounting hole 61, a drive gear mounting position 62, a driven gear mounting position 63, and a sleeve mounting hole 64. The driven gear mounting position 63, the sleeve mounting hole 64, and the center of the aluminum cover 32 are on the same axis from bottom to top. The drive gear mounting position 62 and the driven gear mounting position 63 are arranged parallel to each other. The drive gear 51 is placed in the drive gear mounting position 62, the driven gear 52 is placed in the driven gear mounting position 63, and the lower half of the sleeve 53 is placed in the sleeve mounting hole 64. The motor 9 is fixedly installed in the motor mounting hole 61 by screws. The motor 9 is placed below the mounting bracket 6, and its output shaft 91 is facing upward. The output shaft 91 of the motor 9 passes through the center hole of the drive gear 51 and is interference-fitted with the center hole. The external teeth of the driving gear 51 mesh with the external teeth of the driven gear 52. The upper surface of the driven gear 52 is fixed to the bottom end of the sleeve 53 by screws. A bearing 54 is interference-fitted onto the outer wall of the lower half of the sleeve 53. The outer ring of the bearing 54 is interference-fitted with the sleeve mounting hole 64, so that the sleeve 53, bearing 54 and driven gear 52 are fixed on the mounting bracket 6. In this embodiment, in order to prevent the interference fit between the bearing 54 and the inner wall of the sleeve mounting hole 64 from failing after a period of use, a fixing member 55 is provided on the lower surface of the outer ring of the bearing 54 to keep the bearing 54 always in the sleeve mounting hole 64. The fixing member 55 is fixed to the lower surface of the mounting bracket 6. The fixing member 55 is also provided with a driven gear receiving position 550. If the interference fit between the inner ring of the bearing 54 and the outer wall of the sleeve 53 fails, the fixing member 55 can support the driven gear 52 and the sleeve 53.

[0040] like Figure 4 and Figure 5As shown, the top of the sleeve 53 protrudes through the central through-hole of the inner shell 12 and is placed inside the outer spring 33, with its top surface below the aluminum cover 32. A magnetic ring mounting position 530 is provided extending outward from the top of the sleeve 53, and the magnetic ring 8 is fixed in the magnetic ring mounting position 530 by screws and nuts; the upper surface of the magnetic ring 8 is slightly lower than the upper surface of the heating plate 3, and when the pot body 13 is placed in the cookware 1, there is a gap between the magnetic ring 8 and the lower surface of the aluminum cover 32. The motor 9 drives the drive gear 51 to rotate, and the drive gear 51 causes the driven gear 52 to rotate through meshing. The driven gear 52 drives the sleeve 53 and the magnetic ring 8 to rotate, so that the magnetic stirring rod (not shown) placed in the center of the pot body 13 rotates with the magnetic ring 8 through magnetic attraction, effectively improving the evenness of heating of the food in the pot during cooking.

[0041] Installation and temperature measurement of the pot bottom detection device 4:

[0042] like Figure 4 and Figure 5 As shown, the pot bottom detection device 4 is installed inside the sleeve 53 and consists of a pot bottom sensor 41, a sensor protective sleeve 42, a sensor base 43, and an inner spring 44 from top to bottom. The probe 410 of the pot bottom sensor 41 protrudes through the top surface of the sleeve 53 and is positioned below the aluminum cover 32. The sensor protective sleeve 42 is fitted over the outside of the pot bottom sensor 41, effectively preventing the temperature probe 410 from being affected by the heat radiation from the heating plate 3, thus ensuring accurate temperature measurement. Simultaneously, the exposed top surface of the probe 410 allows it to directly contact the aluminum cover 32 when the pot body 13 is placed inside the cookware 1, effectively preventing temperature measurement delay. The bottom of the pot bottom sensor 41 is placed inside the sensor base 43. The top end of the inner spring 44 abuts against the sensor base 43, and its bottom end abuts against the driven gear 52. The pot bottom sensor 41 can move up and down within the sleeve 53. To prevent the temperature sensor from detaching from the sleeve 53 when moving upwards, a limiting structure is provided inside the sleeve 53.

[0043] Understandably, in a pot cooker 1 without a motor 9 and a transmission device, the bottom detection device 4 can also be directly installed on the outer shell 11 of the pot cooker 1. The inner spring 44 can directly abut against the inner surface of the outer shell 11, so that the horizontal position of the top surface of the bottom sensor 41 probe 410 is above the heating plate 3 and below the top surface of the aluminum cover 32.

[0044] like Figure 3 and Figure 5As shown, when the pot body 13 is placed inside the cooking vessel 1, the aluminum cover 32 moves downwards to compress the outer spring 33 and the inner spring 44, causing the bottom sensor 41 to abut against the lower surface of the aluminum cover 32. The heating plate 3 directly contacts the bottom surface of the pot body 13, heating the bottom of the pot body 13 to cook the contents. Simultaneously, heat from the bottom of the pot body 13 is conducted to the aluminum cover 32, and the bottom sensor 41 detects the temperature of the aluminum cover 32 to obtain the bottom temperature parameter. In this embodiment, the bottom sensor 41 preferably uses a threaded hexagonal NTC thermistor, which can be screwed and fixed to the sensor protective sleeve 42.

[0045] Advantages of installing the bottom sensor 41: Figure 4 As shown, when there is no pot body 13 inside the cookware 1, the aluminum cover 32 is in its original position. When the heating plate 3 is working, its heat will quickly pass through the gap between the heating plate 3 and the aluminum cover 32. The aluminum cover 32 will heat up rapidly after being subjected to heat radiation. If the bottom temperature sensor is directly fixed to the lower surface of the aluminum cover 32 at this time, the measured temperature will quickly approach the temperature of the heating plate 3. In this embodiment, the inner spring 44 is used so that the bottom sensor 41 only contacts the aluminum cover 32 when the pot body 13 is placed inside the cookware 1. This can provide data support for the main control center of the cookware 1 to determine whether there is a pot body 13 inside the cookware 1, and avoid the situation of dry burning of the cookware 1 without a pot.

[0046] If the bottom sensor 41 is directly fixed to the pot body 13 and placed inside the cooking vessel 1, the top surface of the sensor can just touch the aluminum cover 32, which can also achieve the advantage of accurate temperature measurement in this embodiment. However, this method requires very high installation accuracy of the sensor. Also, when the bottom of the pot body 13 deforms due to long-term heating, the position of the aluminum cover 32 may change, and a gap will be created between the bottom sensor 41 and the aluminum cover 32, which will reduce the accuracy of temperature measurement.

[0047] Furthermore, in this embodiment, the pot 1 can simultaneously drive the stirring rod inside the pot and monitor the temperature of the bottom of the pot in real time. The bottom detection device 4 is installed in the transmission device. The transmission and detection work independently and do not affect each other. The overall structure is compact and saves space.

[0048] II. Control of Abnormal Operating Status of Cooking Pot 1

[0049] After the main control center of the cooker 1 starts working (the lid 2 is closed on the pot opening, and the heating plate 3 is turned on to heat up), it can monitor the temperature at various points in real time. By receiving feedback from the three sensors—the temperature inside the pot, the temperature at the bottom of the pot, and the temperature of the heating plate 3—it judges the working status of the cooker 1 based on the magnitude of these three temperature values ​​and their trends over time. When the cooker 1 is determined to be in a state of dry burning without a pot, dry burning with a pot, accidental burning dry, or the lid 2 being opened midway, the main control center sends a command to the heating plate 3 to stop working. This is to prevent overheating of various parts of the cooker 1, which would affect its service life, and to effectively improve the intelligent control of the cooker 1, providing a better user experience.

[0050] 1. Judging the state of dry burning without a pot

[0051] Dry burning without a pot refers to the state where the pot body 13 is not inside the cookware 1.

[0052] like Figure 2 As shown, when there is no pot inside the cookware 1, the aluminum cover 32 pops up. If the cookware 1 is started at this time, the heat emitted by the heating plate 3 will be quickly transferred to the space enclosed by the inner shell 12 of the cookware 1. At this time, the temperature in this space rises rapidly, and because there is no pot body 13 to block it, the heat rises rapidly. Meanwhile, the probe 410 of the bottom sensor 41 does not touch the aluminum cover 32, and because the aluminum cover 32 blocks it, the temperature value it detects is lower than the temperature value detected by the sensor 21 inside the pot at the same time.

[0053] Therefore, after the heating plate 3 has been operating for a short period of time, preferably between 8 and 25 seconds after the heating plate 3 has been operating in this embodiment, if the temperature inside the pot remains higher than the temperature at the bottom of the pot for 5-10 seconds (the specific time can be determined based on the size of the space inside the inner shell 12), it is considered that the pot 1 is in an unloaded state of dry burning without a pot, and the main control center of the pot 1 sends a stop command to the heating plate 3. This judgment mode can also replace the pressure sensor and other existing technologies to detect whether the pot body 13 is placed inside the pot 1, saving production costs.

[0054] 2. Judging the state of a dry-burning pot

[0055] Dry burning with a pot means that after the pot 1 is turned on, there is a pot inside the pot 1, but no food (food, such as water and ingredients) inside the pot body 13.

[0056] Combination Figure 3 and Figure 5As shown, at this time, the bottom surface of the pot body 13 touches the aluminum cover 32 and causes the aluminum cover 32 to move downward. After the cooking pot 1 is started, the heat from the heating plate 3 is quickly transferred to the bottom surface of the pot body 13. The heat from the bottom surface of the pot body 13 is transferred to the bottom sensor 41 through the aluminum cover 32. Therefore, the bottom sensor 41 detects a faster rate of temperature rise, and the rate of temperature rise is similar to that of the heating plate 3 (if there is food in the pot, most of the heat absorbed by the bottom surface of the pot body 13 will be absorbed by the food, and the rate of temperature rise of the bottom of the pot is much smaller than that of the heating plate 3). The sensor 21 inside the pot detects the internal temperature of the pot body 13. Since most of the heat is absorbed by the pot body 13, the temperature of the air inside the pot body 13 rises more slowly than that of the pot body 13, and the temperature inside the pot is always lower than the temperature of the bottom of the pot.

[0057] Therefore, after the heating plate 3 has been turned on for a short period of time, preferably between 8 and 25 seconds after the heating plate 3 has been turned on in this embodiment, when the temperature change of the bottom of the pot and the temperature of the heating plate 3 per unit time tends to be the same and is maintained for 20-30 seconds (the specific time can be determined according to the heat capacity of the material of the pot body 13), and at the same time the temperature inside the pot is always lower than the temperature of the bottom of the pot, it is considered that the pot is dry-burning, and the main control center of the cookware 1 sends a stop working command to the heating plate 3.

[0058] 3. Judging the dryness of the pot body during cooking.

[0059] "Drying out of the pot 13 during cooking" means that the water inside the pot 13 is dried out during the operation of the cookware 1.

[0060] During the operation of the cooker 1, after the water in the pot reaches a boiling state, the temperature detected by the sensor 21 inside the pot will be within a constant range (this constant range is the temperature of the water vapor detected by the sensor 21 inside the pot when the water boils, and is set to different ranges depending on the atmospheric pressure at which the all-in-one machine 100 is operating; under normal atmospheric pressure, the constant range is 98℃-103℃). After the water in the pot body 13 is boiled dry, no water vapor is generated. At this time, the temperature detected by the sensor 21 inside the pot will drop, deviating from the constant range, and then continue to rise, while the heating plate 3 continues to heat, and the temperature of the heating plate 3 and the bottom of the pot continue to rise.

[0061] Therefore, during the normal operation of the heating plate 3, if the temperature inside the pot suddenly drops from a constant range for 20 seconds (this time can be determined according to the amount of food and the water content of the food in the pot 13), and the temperature of the bottom of the pot and the temperature of the heating plate 3 are still rising, it is considered an accidental burn-out, and the main control center of the cookware 1 sends a stop working command to the heating plate 3.

[0062] 4. Check the status by opening the lid midway.

[0063] During the operation of the pot 1, after the water in the pot reaches a boiling state, the temperature detected by the sensor 21 inside the pot will be within a constant range (this constant range is the temperature of water vapor detected by the sensor 21 inside the pot when the water boils under normal atmospheric pressure: 98℃-103℃). At this time, if the pot lid 2 is opened, the sensor 21 inside the pot will directly detect the ambient temperature, and the temperature inside the pot detected by the sensor will drop rapidly, while the heating plate 3 will continue to heat, and the temperature of the heating plate 3 and the bottom of the pot will continue to rise.

[0064] Therefore, during the normal operation of the heating plate 3, if the temperature inside the pot suddenly drops from a constant range within 20 seconds, while the temperature of the bottom of the pot and the temperature of the heating plate 3 are still rising, it is considered that the pot lid 2 is opened midway, and the main control center of the cookware 1 sends a stop working command to the heating plate 3.

[0065] During the operation of the pot 1, before the pot reaches the boiling state, the temperature inside the pot is continuously rising. If the pot lid 2 is opened at this time, the sensor 21 inside the pot will directly detect the ambient temperature. The temperature inside the pot detected by the sensor drops rapidly, while the heating plate 3 continues to heat, and the temperature of the heating plate 3 and the bottom of the pot are still rising.

[0066] Therefore, during the normal operation of the heating plate 3, when the temperature inside the pot suddenly changes from rising to falling, it is considered that the pot lid 2 is opened midway, and the main control center of the cookware 1 sends a stop operation command to the heating plate 3.

[0067] 5. Safety mode during normal operation of cookware 1

[0068] When the temperature of the heating plate 3 reaches the set safety temperature of the heating plate 3, the main control center of the cookware 1 will send a stop working command to the heating plate 3 to protect the internal components of the cookware 1 from damage caused by overheating.

[0069] When the temperature of the bottom of the pot reaches the working temperature set by the cooking program, the main control center of the cookware 1 will switch the working mode of the heating plate 3 to intermittent working mode. In this embodiment, the intermittent working mode is preferably the PID control working mode, which effectively controls the temperature of the bottom of the pot according to the cooking program through closed-loop feedback and effectively saves energy.

Claims

1. A temperature detection device for use in the pot of a multi-functional cooking appliance, characterized in that, It includes three temperature sensors: an in-pot sensor mounted on the lid to detect the temperature of the gas inside the pot, a bottom-pot sensor mounted on the bottom of the pot to detect the temperature of the bottom surface, and a heating plate sensor mounted on the heating plate to detect the surface temperature of the heating plate. After the pot is started, the in-pot temperature, bottom-pot temperature, and heating plate temperature detected by the three sensors are collected. Based on the magnitude of at least two of the three temperature values ​​and their changing trends over time, the pot is judged to be in a state of dry burning without pot, dry burning with pot, accidental burning dry, or pot lid being opened midway. The judgment is then sent to the main control center of the pot, which then issues a stop working command to the heating plate. An aluminum cover that can move up and down elastically is provided in the central through hole of the heating plate. There is a gap between the aluminum cover and the inner wall of the central through hole. An outer spring is provided inside the aluminum cover, and the top of the outer spring abuts against the inner wall of the aluminum cover. The probe of the bottom sensor is placed below the aluminum cover. When the pot is placed in the cookware, the aluminum cover compresses the outer spring and moves downward, and the top surface of the probe directly contacts the aluminum cover.

2. The temperature detection device for a multi-functional cooking appliance according to claim 1, characterized in that, After the heating plate has been working for a short period of time, if the temperature inside the pot is consistently higher than the temperature at the bottom of the pot over time, it is considered that the pot is in an unloaded state of dry burning.

3. The temperature detection device for a multi-functional cooking appliance as described in claim 1, characterized in that, After the heating plate has been working for a short period of time, when the temperature change of the pot bottom and the heating plate per unit time tends to be the same and the temperature inside the pot is lower than the temperature of the pot bottom, it is considered that the pot is dry-burning.

4. The temperature detection device for a multi-functional cooking appliance as described in claim 1, characterized in that, During normal operation of the heating plate, if the temperature inside the pot suddenly drops from a constant range within 10 to 30 seconds, while the temperature of the bottom of the pot and the temperature of the heating plate are still rising, it is considered as an accidental burn-out or the pot lid being opened midway.

5. The temperature detection device for a multi-functional cooking appliance as described in claim 1, characterized in that, During the normal operation of the heating plate, if the temperature inside the pot suddenly changes from rising to falling, it is considered that the pot lid has been opened midway.

6. The temperature detection device for a multi-functional cooking appliance as described in any one of claims 1 to 5, characterized in that, When the temperature of the bottom of the pot reaches the working temperature set by the cooking program, the main control center of the cookware switches the working mode of the heating plate to intermittent working mode.

7. The temperature detection device for a multi-functional cooking appliance as described in claim 6, characterized in that, The in-pot sensor, the bottom-pot sensor, and the heating plate sensor are all thermistors.

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