Heating protection circuit and aerosol generating device

Abstract

The utility model provides a heating protection circuit and an aerosol generating device, the heating protection circuit comprises a sampling output circuit, a comparison circuit and a reset circuit, the sampling output circuit samples the current of a heating circuit and the temperature of a heating body, and outputs a second level signal to trigger the heating circuit to turn off heating output during overcurrent and / or over-temperature; and on the other hand, the reset circuit triggers and outputs the reset signal to the controller after receiving the second level signal, so that when the heating is abnormal due to the abnormal state of the program of the controller, the controller can be reset to the normal state, and the reliability of heating protection is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to heating protection technical field especially relates to a kind of heating protection circuit and aerosol generating device. BACKGROUND

[0002] Heating non-combustion aerosol generating device can heat aerosol generating substrate to generate aerosol, with the advantages of safe, convenient, healthy, environmental protection etc., therefore more and more people's attention and favour. Conventional aerosol generating device includes controller, heating circuit and heating element, controller such as MCU controls heating circuit to work by output enable signal, and heating element is heated, heating element heats aerosol generating substrate, to generate aerosol.

[0003] At present, the heating abnormal hardware protection of aerosol generating device mainly has heating element over-temperature protection, heating element over-current protection etc., when heating occurs abnormally, such as heating element over-temperature or heating element over-current, trigger hardware protection, close the heating output of heating circuit, without controller control, can start protection, improve heating protection efficiency.

[0004] However, the conventional heating protection circuit only closes heating output when triggering hardware protection, and the controller cannot be reset, if the controller program runs abnormally, such as program runaway, MCU dead machine etc., leading to heating anomaly, even if heating protection is triggered and the heating output of heating circuit is closed, the problem of heating anomaly cannot be eliminated, leading to repeated heating and protection cycle of heating circuit, with security risk. INVENTION CONTENTS

[0005] The utility model aims at providing a kind of heating protection circuit, to solve the problem that the heating protection circuit of traditional heating protection circuit cannot realize effective heating protection when controller is abnormal.

[0006] The first aspect of the embodiment of the utility model proposes a kind of heating protection circuit, applied to aerosol generating device, the aerosol generating device includes controller, heating circuit and heating element, the signal output end of the controller is connected with the enable end of the heating circuit, the controller is used to output first level signal control heating element of the heating circuit and output second level signal control the heating element of the heating circuit stops heating, the first level signal and the second level signal are opposite level signals;

[0007] The heating protection circuit includes:

[0008] Sampling output circuit, connected with the heating circuit, the sampling output circuit is used for respectively sampling the current of the heating circuit and the temperature of the heating element, and outputs current sampling signal and temperature sampling signal;

[0009] a comparison circuit connected with the output end of the sampling output circuit and the enable end of the heating circuit respectively, the comparison circuit configured to compare the current sampling signal and the temperature sampling signal with corresponding threshold reference signals respectively, and output a first level signal indicating that the corresponding sampling signal is within the range of the threshold reference signal or output a second level signal indicating that the corresponding sampling signal exceeds the threshold reference signal;

[0010] a reset circuit connected with the signal output end of the controller, the output end of the comparison circuit and the reset end of the controller respectively, the reset circuit configured to output a reset signal to reset the controller triggered by the second level signal output by the comparison circuit.

[0011] Optionally, the sampling output circuit comprises:

[0012] a current sampling circuit connected with the heating circuit, the current sampling circuit configured to sample the working current or output current of the heating circuit and output a current sampling signal;

[0013] a temperature sampling circuit arranged relative to the heating body, the temperature sampling circuit configured to sample the temperature of the heating body and output a temperature sampling signal.

[0014] Optionally, the comparison circuit comprises a first comparator and a second comparator.

[0015] the non-inverting input end of the first comparator is connected with the output end of the current sampling circuit, the non-inverting input end of the first comparator configured to input a first threshold reference voltage, the non-inverting input end of the second comparator is connected with the output end of the temperature sampling circuit, the non-inverting input end of the second comparator configured to input a second threshold reference voltage, and the output end of the first comparator and the output end of the second comparator are connected to constitute the output end of the comparison circuit.

[0016] Optionally, the first comparator and the second comparator are integrated into a comparison chip.

[0017] Optionally, the first level signal is a high level signal and the second level signal is a low level signal.

[0018] the reset circuit comprises:

[0019] a pull-up circuit connected with the reset end of the controller, the pull-up circuit configured to pull up the reset end of the controller to a high level when there is no signal input.

[0020] A signal switching circuit is connected with the signal output end of the controller, the output end of the comparison circuit and the pull-up circuit, and is triggered to turn off the output by the corresponding one of the level signal output by the controller and the first level signal output by the comparison circuit, and is triggered to switch the output low to the pull-up circuit and the reset end of the controller by the second level signal output by the comparison circuit.

[0021] Optionally, the pull-up circuit comprises a first resistor and a first capacitor.

[0022] The first end of the first resistor is connected with the positive power supply end, the second end of the first resistor, the first end of the first capacitor and the reset end of the controller are connected, and the second end of the first capacitor is grounded.

[0023] Optionally, the signal switching circuit comprises a second resistor, a second capacitor, a first electronic switch tube and a second electronic switch tube.

[0024] The first end of the second resistor is connected with the signal output end of the controller, the second end of the second resistor, the control end of the first electronic switch tube, the first end of the second capacitor and the first end of the second electronic switch tube are connected, the control end of the second electronic switch tube is connected with the signal output end of the controller and the output end of the comparison circuit respectively, the second end of the second electronic switch tube is grounded, the second end of the second capacitor is grounded, the second end of the first electronic switch tube is grounded, and the first end of the first electronic switch tube constitutes the output end of the signal switching circuit.

[0025] Optionally, the reset circuit further comprises:

[0026] A voltage dividing circuit, the input end of the voltage dividing circuit is connected with the signal output end of the controller, the voltage dividing output end of the voltage dividing circuit is connected with the enable end of the heating circuit and the output end of the comparison circuit respectively, and the voltage dividing circuit is used for voltage dividing output of the level signal output by the controller.

[0027] Optionally, the voltage dividing circuit comprises a third resistor and a fourth resistor.

[0028] The first end of the third resistor is connected with the signal output end of the controller, the second end of the third resistor, the first end of the fourth resistor, the enable end of the heating circuit, the output end of the comparison circuit and the control end of the signal switching circuit are connected, and the second end of the fourth resistor is grounded.

[0029] The utility model discloses an aerosol generating device, including controller, heating circuit, heating body and the heating protection circuit as described above, the heating protection circuit is connected with the heating circuit and the controller respectively,

[0030] The signal output end of the controller is connected with the enable end of the heating circuit, the controller is used for outputting the first level signal to control the heating circuit to heat the heating body and outputting the second level signal to control the heating circuit to stop heating the heating body, and the first level signal and the second level signal are opposite level signals.

[0031] The utility model discloses an aerosol generating device, including controller, heating circuit, heating body and the heating protection circuit as described above, the heating protection circuit is connected with the heating circuit and the controller respectively, BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical scheme in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0033] Figure 1 The first structure schematic diagram of the aerosol generating device provided by the utility model embodiment is provided.

[0034] Figure 2 The second structure schematic diagram of the aerosol generating device provided by the utility model embodiment is provided.

[0035] Figure 3 The circuit schematic diagram of the comparison circuit provided by the utility model embodiment is provided.

[0036] Figure 4 The third structure schematic diagram of the aerosol generating device provided by the utility model embodiment is provided.

[0037] Figure 5 The fourth structure schematic diagram of the aerosol generating device provided by the utility model embodiment is provided.

[0038] Figure 6 The circuit schematic diagram of the heating protection circuit provided by the utility model embodiment is provided.

[0039] In the drawings, reference numerals refer to:

[0040] 100, controller; 200, heating circuit; 300, heating body; 400, heating protection circuit; 10, sampling output circuit; 20, comparison circuit; 30, reset circuit; 11, current sampling circuit; 12, temperature sampling circuit; 31, pull-up circuit; 32, signal switching circuit; 33, voltage dividing circuit;

[0041] R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; C1, first capacitor; C2, second capacitor; Q1, first electronic switch tube; Q2, second electronic switch tube; U1, first comparator; U2, second comparator; U3, comparison chip;

[0042] VCC, positive power supply end; RESET, reset end; EN, enable end; HEAT_EN, enable signal; rst, reset signal; V1, first voltage; V2, second voltage; VREF1, first threshold reference voltage; VREF2, second threshold reference voltage. DETAILED DESCRIPTION

[0043] In order to make the technical problems, technical solutions and beneficial effects to be solved by the utility model more clearly understood, the utility model will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and not used to limit the utility model.

[0044] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as "first" and "second" can explicitly or implicitly include one or more features. In the description of the utility model, the meaning of "multiple" is two or more than two, unless otherwise specifically limited.

[0045] The first aspect of the embodiment of the utility model proposes a kind of heating protection circuit 400, it is applied to aerosol generating device, aerosol generating device includes controller 100, heating circuit 200 and heating body 300, the signal output end of controller 100 is connected with the enable end EN of heating circuit 200, controller 100 is used to output first level signal control heating circuit 200 heating heating body 300 and output second level signal control heating circuit 200 stop heating heating body 300, first level signal and second level signal are opposite level signal.

[0046] The aerosol generating device further comprises a power module and an atomization cavity. The power module is configured to provide a power supply to the controller 100 and the heating circuit 200. The controller 100 can be an MCU, a single-chip microcomputer, an FPGA, or the like.

[0047] The heating element 300 can be a heating wire or a substrate strip. When the heating element 300 is a heating wire, the aerosol generating substrate is arranged in the atomization cavity. The heating circuit 200 is directly connected to the heating wire. The heating wire is arranged adjacent to or inside the atomization cavity. The heating circuit 200 outputs a heating current to the heating wire under the control of the enable signal HEAT_EN. After the heating wire is heated, the heating wire can heat the aerosol generating substrate to generate aerosol for a user to smoke. Correspondingly, the heating circuit 200 can adopt a power conversion circuit. The power conversion circuit converts the received power supply into a heating current to the heating wire according to the enable signal HEAT_EN.

[0048] When the heating wire is a substrate strip, the substrate strip is arranged in the magnetic field generated by the heating circuit 200. The surface of the substrate strip is coated with or internally permeated or embedded with an aerosol generating substrate for generating aerosol. The heating circuit 200 can be an LC resonant circuit. The LC resonant circuit can include an inductor, a capacitor, and a switch. The switch receives a power supply and a PWM signal to make the inductor and the capacitor resonate and generate a magnetic field. The inductor is at least partially arranged in the atomization cavity. The generated magnetic field is emitted to the atomization cavity and heats the substrate strip, thereby heating the aerosol generating substrate to generate aerosol for a user to smoke.

[0049] The signal output end of the controller 100 is connected to the enable end EN of the heating circuit 200. When starting the heating work or the normal heating work, the controller 100 outputs a first level signal. The heating circuit 200 outputs a heating current or generates a magnetic field to the heating element 300. The heating element 300 generates heat to the aerosol generating substrate and generates aerosol for a user to smoke.

[0050] When stopping the heating work, the controller 100 outputs a second level signal opposite to the first level signal. The heating circuit 200 stops outputting the heating current or closes the magnetic field under the control of the second level signal. The heating element 300 stops heating the aerosol generating substrate.

[0051] The first level signal and the second level signal can be high and low levels, respectively. The specific signal type can be set according to requirements.

[0052] In an optional embodiment, the first level signal is a high level signal, and the second level signal is a low level signal. The controller 100 outputs a high level control to make the heating circuit 200 work, and outputs a low level control to make the heating circuit 200 stop working and close the output.

[0053] In order to realize heating protection in various abnormal states, including heating circuit 200 abnormality, controller 100 abnormality, etc., as shown in the embodiment, the heating protection circuit 400 includes: Figure 1

[0054] The sampling output circuit 10 is connected with the heating circuit 200, and the sampling output circuit 10 is used for sampling the current of the heating circuit 200 and the temperature of the heating body 300 respectively, and outputting the current sampling signal and the temperature sampling signal;

[0055] The comparison circuit 20 is connected with the output end of the sampling output circuit 10 and the enable end EN of the heating circuit 200 respectively, and the comparison circuit 20 is used for comparing the current sampling signal and the temperature sampling signal with the corresponding threshold reference signal respectively, and outputting the first level signal representing that the corresponding sampling signal is within the threshold reference signal or outputting the second level signal representing that the corresponding sampling signal exceeds the threshold reference signal;

[0056] The reset circuit 30 is connected with the signal output end of the controller 100, the output end of the comparison circuit 20 and the reset end RESET of the controller 100 respectively, and the reset circuit 30 is triggered to output the reset signal rst of the controller 100 by the second level signal output by the comparison circuit 20.

[0057] In the embodiment, the sampling output circuit 10 samples the current of the heating circuit 200 and the temperature of the heating body 300 in real time, wherein when the heating circuit 200 is a power conversion circuit, the current can be the output current of the heating circuit 200, and when the heating circuit 200 is an LC resonant circuit, the current can be the working current of the heating circuit 200, and the sampling output circuit 10 can also be provided with a corresponding temperature sensitive device and be arranged adjacent to or in contact with the heating body 300, and the temperature of the heating body 300 is detected.

[0058] When the controller 100 is in a normal working state and the aerosol generating device is normally heated, the current of the heating circuit 200 does not appear overcurrent, and the temperature of the heating body 300 does not appear overtemperature, at this time, the current sampling signal and the temperature sampling signal output by the sampling output circuit 10 are within the range of the threshold reference signal, the comparison circuit 20 outputs the first level signal to the enable end EN of the heating circuit 200, and the heating circuit 200 continues to maintain the heating work. And the reset circuit 30 does not receive the second level signal output by the comparison circuit 20, the reset circuit 30 does not output the reset signal rst to the controller 100, and the controller 100 normally outputs the first level signal.

[0059] ​When the protection is triggered, for example, the heating circuit 200 is abnormal or the controller 100 is abnormal, resulting in over-temperature and / or over-current, at this time, the sampling output circuit 10 detects that the current sampling signal and / or the temperature sampling signal exceeds the threshold reference signal, at this time, the comparison circuit 20 outputs the second level signal to the enable end EN of the heating circuit 200 and the reset circuit 30, the heating circuit 200 stops heating the heating body 300, at the same time, the reset circuit 30 receives the second level signal and triggers the reset signal rst output to the controller 100, the controller 100 generates a reset, at the same time, due to the reset of the controller 100, the level of the signal output end of the controller 100 becomes the second level signal, the heating circuit 200 maintains the stop working state, and since the reset circuit 30 only generates the reset signal rst under the control of the second level signal output by the comparison circuit 20, the reset circuit 30 has no reset signal rst output when receiving the second level signal output by the controller 100, the controller 100 will not be reset repeatedly, and the controller 100 and the entire aerosol generating device can restore the normal working state.

[0060] When the aerosol generating device starts heating, the controller 100 outputs the first level signal to the enable end EN of the heating circuit 200 and the reset circuit 30, the heating circuit 200 enables the heating work to start, and since the reset circuit 30 only generates the reset signal rst under the control of the second level signal output by the comparison circuit 20, the reset circuit 30 has no reset signal rst output when receiving the first level signal output by the controller 100, and the controller 100 has no reset action.

[0061] Similarly, when the aerosol generating device stops heating, the controller 100 switches to output the second level signal to the enable end EN of the heating circuit 200 and the reset circuit 30, the heating circuit 200 enables the output to be closed, and since the reset circuit 30 only generates the reset signal rst under the control of the second level signal output by the comparison circuit 20, the reset circuit 30 has no reset signal rst output when receiving the second level signal output by the controller 100, and the controller 100 has no reset action.

[0062] By setting the sampling output circuit 10, the comparison circuit 20 and the reset circuit 30, the reset of the controller 100 and the closed output control of the heating circuit 200 can be realized when the controller 100 is abnormal or the heating circuit 200 is abnormal, improving the reliability and safety of the heating protection.

[0063] Among them, the sampling output circuit 10 can be provided with corresponding current sampling and temperature sampling structures based on the detection sampling object, in an optional embodiment, as shown in Figure 2 The sampling output circuit 10 comprises:

[0064] The current sampling circuit 11 is connected with the heating circuit 200, and is configured to sample the working current or output current of the heating circuit 200 and output a current sampling signal.

[0065] The temperature sampling circuit 12 is arranged relative to the heating body 300, and is configured to sample the temperature of the heating body 300 and output a temperature sampling signal.

[0066] In the embodiment, the current sampling circuit 11 can be connected inside the heating circuit 200 or at the output end of the heating circuit 200 according to the type of the heating circuit 200, and detect the working current or output current of the heating circuit 200 and output the current sampling signal to the comparison circuit 20 in real time.

[0067] The current sampling circuit 11 can be implemented by using structures such as series resistors and current transformers.

[0068] The temperature sampling circuit 12 can be arranged adjacent to or on the heating body 300, and sample the temperature of the heating body 300 in real time. The temperature of the heating body 300 can be the self temperature or the ambient temperature of the current heating body 300, and the specific temperature object to be detected is not limited.

[0069] The temperature sampling circuit 12 can be implemented by using temperature-sensitive elements such as temperature-sensitive resistors and temperature sensors.

[0070] The comparison circuit 20 can be implemented by using corresponding comparators and switch tubes. For example, when a switch tube is used, the sampling signal is output to the control end of the switch tube. When the sampling signal exceeds the threshold reference signal, the sampling signal exceeds the threshold voltage of the switch tube, the switch tube is turned on and outputs a second level signal. When the switch tube is not turned on, the switch tube outputs a first level signal.

[0071] In an optional embodiment, as shown in FIG. 2, the comparison circuit 20 includes a first comparator U1 and a second comparator U2 corresponding to two sampling circuits. Figure 3

[0072] The inverting input end of the first comparator U1 is connected with the output end of the current sampling circuit 11, the non-inverting input end of the first comparator U1 is configured to input a first threshold reference voltage VREF1, the inverting input end of the second comparator U2 is connected with the output end of the temperature sampling circuit 12, the non-inverting input end of the second comparator U2 is configured to input a second threshold reference voltage VREF2, and the output end of the first comparator U1 and the output end of the second comparator U2 are connected to form the output end of the comparison circuit 20.

[0073] ​In this embodiment, the comparison is based on the voltage signal, the current sampling circuit 11 outputs the first voltage V1 representing the size of the current sampling signal, the temperature sampling circuit 12 outputs the second voltage V2 representing the size of the temperature sampling signal, the first voltage V1 is compared with the first threshold reference voltage VREF1, and the second voltage V2 is compared with the second threshold reference voltage VREF2.

[0074] In normal heating, the current of the heating circuit 200 does not overcurrent, the first voltage V1 is less than the first threshold reference voltage VREF1, and / or the temperature of the heat generator 300 does not overheat, the second voltage V2 is less than the second threshold reference voltage VREF2, at this time, the first comparator U1 outputs high level and / or the second comparator U2 outputs high level, the reset circuit 30 receives high level and outputs no reset signal rst, and the controller 100 maintains normal working state.

[0075] In abnormal state, the current of the heating circuit 200 overflows, the first voltage V1 is greater than the first threshold reference voltage VREF1, and / or the temperature of the heat generator 300 overflows, the second voltage V2 is greater than the second threshold reference voltage VREF2, at this time, the first comparator U1 outputs low level and / or the second comparator U2 outputs low level, the comparison circuit 20 as a whole outputs low level, the reset circuit 30 receives low level signal and triggers the output of the reset signal rst to the controller 100, the controller 100 is reset, at the same time, the signal output end of the controller 100 switches to output low level signal, controls the heating circuit 200 to stop working and closes the output.

[0076] In order to simplify the structure of the overcurrent protection circuit, in an optional embodiment, as shown in Figure 6 The first comparator U1 and the second comparator U2 are integrated into the comparison chip U3, the inverting input end and the non-inverting input end of the first comparator U1 and the inverting input end and the non-inverting input end of the second comparator U2 respectively constitute four different signal input ends of the comparison chip U3 and respectively receive the first voltage V1, the second voltage V2, the first threshold reference voltage VREF1 and the second threshold reference voltage VREF2, at the same time, the output end of the first comparator U1 and the output end of the second comparator U2 are connected in common to constitute the signal output end of the comparison chip U3 and are used to output the level signal after comparison.

[0077] The reset circuit 30 can adopt reset chip, switching circuit, etc., and is based on the received signals of different positions and different types to switch or cut off the output of the reset signal rst, in an optional embodiment, as shown in Figure 4 The reset circuit 30 includes:

[0078] The pull-up circuit 31 is connected with the reset end RESET of the controller 100, and the pull-up circuit 31 pulls up the reset end RESET of the controller 100 to high level when no signal is inputted;

[0079] The signal switching circuit 32 is connected with the signal output end of the controller 100, the output end of the comparison circuit 20 and the pull-up circuit 31 respectively. The signal switching circuit 32 is triggered to turn off the output by the corresponding one of the level signal outputted by the controller 100 and the first level signal outputted by the comparison circuit 20, and is triggered to switch the output low level to the pull-up circuit 31 and the reset end RESET of the controller 100 by the second level signal outputted by the comparison circuit 20.

[0080] In the embodiment, the signal switching circuit 32 only outputs the low level reset signal rst when receiving the second level signal outputted by the comparison circuit 20, and keeps turning off the output in other cases.

[0081] When the controller 100 is in the normal working state and the aerosol generating device is normally heated, the current of the heating circuit 200 does not overflows, and the temperature of the heating element 300 does not overheat. At this time, the current sampling signal and the temperature sampling signal outputted by the sampling output circuit 10 are both in the range of the threshold reference signal, the comparison circuit 20 outputs high level to the enable end EN of the heating circuit 200, and the heating circuit 200 continues to maintain the heating work. Moreover, the signal switching circuit 32 does not receive the low level signal outputted by the comparison circuit 20, the signal switching circuit 32 does not output the low level reset signal rst to the controller 100 and the pull-up circuit 31, the pull-up circuit 31 maintains the pull-up work, and the reset end RESET of the controller 100 is maintained at high level, the controller 100 has no reset action, and the first level signal is normally outputted.

[0082] When the protection is triggered, for example, the heating circuit 200 is abnormal or the controller 100 is abnormal, resulting in over-temperature and / or over-current, at this time, the sampling output circuit 10 detects that the current sampling signal and / or the temperature sampling signal exceeds the threshold reference signal, at this time, the comparison circuit 20 outputs the low-level second level signal to the enable end EN of the heating circuit 200 and the signal switching circuit 32, the heating circuit 200 stops heating the heating body 300, at the same time, the signal switching circuit 32 receives the low-level second level signal and triggers to output the low-level reset signal rst to the controller 100 and the pull-up circuit 31, the controller 100 generates a reset, at the same time, due to the reset of the controller 100, the level of the signal output end of the controller 100 becomes the low-level second level signal, the heating circuit 200 maintains the stop working state, and since the signal switching circuit 32 generates the reset signal rst only under the control of the low-level second level signal output by the comparison circuit 20, the signal switching circuit 32 has no low-level reset signal rst output when receiving the second level signal output by the controller 100, the reset end RESET of the controller 100 is switched to high level due to the pull-up action of the pull-up circuit 31, the controller 100 will not be reset repeatedly, and the controller 100 and the entire aerosol generating device can restore the normal working state.

[0083] When the aerosol generating device starts heating, the controller 100 outputs high level to the enable end EN of the heating circuit 200 and the signal switching circuit 32, the heating circuit 200 enables to start heating work, and since the signal switching circuit 32 generates the low-level reset signal rst only under the control of the low-level output by the comparison circuit 20, the reset end RESET of the controller 100 is maintained at high level due to the pull-up action of the pull-up circuit 31, and the controller 100 will not be reset.

[0084] Similarly, when the aerosol generating device stops heating, the controller 100 switches to output low level to the enable end EN of the heating circuit 200 and the signal switching circuit 32, the heating circuit 200 enables to close output, and since the signal switching circuit 32 generates the low-level reset signal rst only under the control of the low-level output by the comparison circuit 20, the reset end RESET of the controller 100 is maintained at high level due to the pull-up action of the pull-up circuit 31, and the controller 100 will not be reset.

[0085] Wherein, the pull-up circuit 31 can adopt structures such as pull-up resistance, pull-up chip, etc., and the signal switching circuit 32 can adopt structures such as switching chip, switching circuit, etc., in an optional embodiment, as shown in Figure 6 The pull-up circuit 31 includes a first resistance R1 and a first capacitor C1;

[0086] The first end of the first resistor R1 is connected with the positive power supply end VCC, the second end of the first resistor R1, the first end of the first capacitor C1 and the reset end RESET of the controller 100 are connected, and the second end of the first capacitor C1 is grounded.

[0087] The signal switching circuit 32 comprises a second resistor R2, a second capacitor C2, a first electronic switch Q1 and a second electronic switch Q2.

[0088] The first end of the second resistor R2 is connected with the signal output end of the controller 100, the second end of the second resistor R2, the control end of the first electronic switch Q1, the first end of the second capacitor C2 and the first end of the second electronic switch Q2 are connected, the control end of the second electronic switch Q2 is connected with the signal output end of the controller 100 and the output end of the comparison circuit 20 respectively, the second end of the second electronic switch Q2 is grounded, the second end of the second capacitor C2 is grounded, the second end of the first electronic switch Q1 is grounded, and the first end of the first electronic switch Q1 constitutes the output end of the signal switching circuit 32.

[0089] In the embodiment, when the controller 100 is in the normal working state, the controller 100 outputs a high level to the enable end EN of the heating circuit 200, and the current of the heating circuit 200 does not overflows when the aerosol generating device is normally heated, at this time, the comparison circuit 20 outputs a high level to the enable end EN of the heating circuit 200, the heating circuit 200 continues to maintain the heating work, and the second electronic switch Q2 is triggered to be turned on after receiving the high level, the first electronic switch Q1 is triggered to be turned off after receiving the low level transmitted by the second electronic switch Q2, the first resistor R1 maintains the pull-up work, and maintains the reset end RESET of the controller 100 at a high level, the controller 100 has no reset action, and normally outputs the first level signal.

[0090] When the protection is triggered, for example, the heating circuit 200 is abnormal or the controller 100 works abnormally, resulting in over-temperature and / or over-current, at this time, the comparison circuit 20 outputs a low level to the enable end EN of the heating circuit 200 and the second electronic switch Q2, the heating circuit 200 stops heating the heating body 300, at the same time, the second electronic switch Q2 is triggered to be turned off, the first electronic switch Q1 receives a high level through the second resistor R2, the first electronic switch Q1 is triggered to be turned on and outputs a low level to the first resistor R1 and the controller 100, the controller 100 generates a reset, at the same time, due to the reset of the controller 100, the level of the signal output end of the controller 100 becomes a low level, the heating circuit 200 maintains the stop working state, and the first electronic switch Q1 is triggered to be turned off, the first resistor R1 outputs a high level to the reset end RESET of the controller 100, the controller 100 will not be reset repeatedly, and the controller 100 and the whole aerosol generating device can restore the normal working state.

[0091] When the aerosol-generating device starts heating, the controller 100 outputs a high level to the enable end EN of the heating circuit 200, the first electronic switch tube Q1 and the second electronic switch tube Q2, the heating circuit 200 enables to start heating work, and the second capacitor C2 exists, so the voltage of the control end of the second electronic switch tube Q2 rises faster, the second electronic switch tube Q2 is turned on first, and because the second electronic switch tube Q2 is turned on, a low level is output to the first electronic switch tube Q1 and the second capacitor C2 is discharged, the first electronic switch tube Q1 is turned off, the reset end RESET of the controller 100 is cut off, the first resistor R1 outputs a high level to the reset end RESET of the controller 100, and the controller 100 will not reset.

[0092] Similarly, when the aerosol-generating device stops heating, the controller 100 switches to output a low level to the enable end EN of the heating circuit 200, the first electronic switch tube Q1 and the second electronic switch tube Q2, the heating circuit 200 enables to stop outputting, and because the first electronic switch tube Q1 is in a low level before the heating is turned off, the control end of the first electronic switch tube Q1 is maintained at a low level due to the presence of the second capacitor C2, the first electronic switch tube Q1 is maintained in a turned-off state, the reset end RESET of the controller 100 is cut off, the first resistor R1 outputs a high level to the reset end RESET of the controller 100, and the controller 100 will not reset.

[0093] Among them, based on the switching on-off mode, the first electronic switch tube Q1 and the second electronic switch tube Q2 can select the corresponding type of MOS tube and triode, in an optional embodiment, the first electronic switch tube Q1 is a first NMOS tube or a first NPN triode, the drain, source and gate of the first NMOS tube respectively constitute the first end, the second end and the control end of the first electronic switch tube Q1, or the collector, emitter and base of the first NPN triode respectively constitute the first end, the second end and the control end of the first electronic switch tube Q1, the first NMOS tube or the first NPN triode is triggered to turn on under receiving a corresponding high level and is triggered to turn off under receiving a corresponding low level.

[0094] The second electronic switch tube Q2 is a second NMOS tube or a second NPN triode, the drain, source and gate of the second NMOS tube respectively constitute the first end, the second end and the control end of the second electronic switch tube Q2, or the collector, emitter and base of the second NPN triode respectively constitute the first end, the second end and the control end of the second electronic switch tube Q2, the second NMOS tube or the second NPN triode is triggered to turn on under receiving a corresponding high level and is triggered to turn off under receiving a corresponding low level, for example Figure 6 As shown, the first electronic switch tube Q1 and the second electronic switch tube Q2 both use NMOS tubes.

[0095] Meanwhile, in order to match the voltage between the signal output end of the controller 100 and the enable end EN of the heating circuit 200, and balance the voltage between the signal output end of the controller 100 and the output end of the comparison circuit 20 and the reset circuit 30, in an optional embodiment, the reset circuit 30 further comprises:

[0096] a voltage dividing circuit 33, an input end of the voltage dividing circuit 33 is connected with the signal output end of the controller 100, voltage dividing output ends of the voltage dividing circuit 33 are respectively connected with the enable end EN of the heating circuit 200 and the output end of the comparison circuit 20, and the voltage dividing circuit 33 is used for voltage dividing output of the high level signal output by the controller 100.

[0097] By means of the voltage dividing setting of the voltage dividing circuit 33, the high level output by the controller 100 can be voltage divided, so as to avoid the influence of the too high voltage on the working performance of the comparison circuit 20, the reset circuit 30 and the heating circuit 200.

[0098] The voltage dividing circuit 33 can adopt corresponding voltage dividing resistor, voltage reducing circuit and the like structure, in order to simplify the circuit structure, in an optional embodiment, the voltage dividing circuit 33 comprises a third resistor R3 and a fourth resistor R4.

[0099] A first end of the third resistor R3 is connected with the signal output end of the controller 100, a second end of the third resistor R3, a first end of the fourth resistor R4, the enable end EN of the heating circuit 200, the output end of the comparison circuit 20 and a control end of the signal switching circuit 32 are connected, and a second end of the fourth resistor R4 is grounded.

[0100] The third resistor R3 and the fourth resistor R4 constitute voltage dividing resistors, and voltage divide the high level signal output by the controller 100, so as to provide corresponding size voltage signal to the comparison circuit 20, the reset circuit 30 and the heating circuit 200, and avoid the influence of the too high voltage on the working performance of the comparison circuit 20, the reset circuit 30 and the heating circuit 200.

[0101] And when the controller 100 outputs low level signal, the fourth resistor R4 maintains the pull-down working.

[0102] The beneficial effects of the embodiment of the utility model compared with prior art are that: the heating protection circuit 400 includes sampling output circuit 10, comparison circuit 20 and reset circuit 30, sampling output circuit 10 samples the current of heating circuit 200 and the temperature of heat generator 300, and outputs second level signal to trigger heating circuit 200 to shut down heating output when overcurrent and / or overtemperature, on the other hand, reset circuit 30 triggers output reset signal rst to controller 100 after receiving second level signal, when heating abnormality caused by abnormal state of controller 100 program, the reset of controller 100 can be realized to make controller 100 reset to normal state, improve the reliability of heating protection.

[0103] The second aspect of the embodiment of the utility model proposes an aerosol generating device, the aerosol generating device includes controller 100, heating circuit 200, heat generator 300 and heating protection circuit 400, the specific structure of heating protection circuit 400 refers to the above embodiment, because the aerosol generating device adopts all the technical solutions of the above embodiment, at least has all the beneficial effects brought by the technical solutions of the above embodiment, which will not be repeated here. Among them, heating protection circuit 400 is connected with heating circuit 200 and controller 100 respectively;

[0104] The signal output end of controller 100 is connected with the enable end EN of heating circuit 200, and controller 100 is used for outputting first level signal to control heating circuit 200 to heat heat generator 300 and outputting second level signal to control heating circuit 200 to stop heating heat generator 300, and the first level signal and the second level signal are opposite level signals.

[0105] Among them, the aerosol generating device is also provided with power module and atomization cavity, and the power module is used for providing power supply to controller 100 and heating circuit 200, and the controller 100 can be MCU, single-chip microcomputer, FPGA and the like.

[0106] Heat generator 300 can be heating wire or substrate strip, when heat generator 300 is heating wire, aerosol generating substrate is arranged in atomization cavity, heating circuit 200 can be directly connected with heating wire, heating wire is arranged adjacent to atomization cavity or in the inside of atomization cavity, and heating circuit 200 outputs heating current to heating wire under the control of enable signal HEAT_EN, and heating wire can heat aerosol generating substrate to generate aerosol for user to smoke after heating, correspondingly, heating circuit 200 can adopt power conversion circuit, and according to enable signal HEAT_EN, the received power supply is converted into heating current to heating wire.

[0107] When the heating wire is a substrate strip, the substrate strip is arranged in a magnetic field range generated by the heating circuit 200, a surface of the substrate strip is coated or internally infiltrated or embedded with an aerosol generating substrate for generating an aerosol, the heating circuit 200 can be an LC resonant circuit, the LC resonant circuit can include an inductor, a capacitor and a switch, the switch receives a power supply and a PWM signal to make the inductor and the capacitor resonate and generate a magnetic field, the inductor is at least partially arranged in the atomization cavity, the generated magnetic field is emitted to the atomization cavity and heats the substrate strip, so that the aerosol generating substrate is heated to generate an aerosol for a user to smoke.

[0108] The signal output end of the controller 100 is connected with the enable end EN of the heating circuit 200, when starting the heating work or the normal heating work, the controller 100 outputs a first level signal, the heating circuit 200 outputs a heating current or generates a magnetic field to the heating body 300, the heating body 300 generates heat to the aerosol generating substrate, and generates an aerosol for a user to smoke.

[0109] When stopping the heating work, the controller 100 outputs a second level signal opposite to the first level signal, the heating circuit 200 stops outputting the heating current or closes the magnetic field under the control of the second level signal, and the heating body 300 stops heating the aerosol generating substrate.

[0110] The first level signal and the second level signal can be high and low levels, and the specific signal type can be set according to the requirements.

[0111] The heating protection circuit 400 samples and compares the temperature of the heating circuit 200 and the heating body 300, and outputs a reset signal to reset the controller 100 in an abnormal state, so that the controller 100 is reset to a normal state, and the reliability of the heating protection is improved.

[0112] The above-described embodiments are only used to illustrate the technical solutions of the present application, but not limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A heating protection circuit applied to an aerosol generating device, characterized in that, The aerosol generating device comprises a controller, a heating circuit and a heating body, a signal output end of the controller is connected with an enable end of the heating circuit, the controller is used for outputting a first level signal to control the heating circuit to heat the heating body and outputting a second level signal to control the heating circuit to stop heating the heating body, the first level signal and the second level signal are opposite level signals; The heating protection circuit comprises: A sampling output circuit connected with the heating circuit, the sampling output circuit is used for sampling current of the heating circuit and temperature of the heating body respectively and outputting current sampling signals and temperature sampling signals; A comparison circuit connected with output ends of the sampling output circuit and an enable end of the heating circuit respectively, the comparison circuit is used for comparing the current sampling signals and the temperature sampling signals with corresponding threshold reference signals respectively and outputting a first level signal representing that the corresponding sampling signals are within the threshold reference signal range or outputting a second level signal representing that the corresponding sampling signals exceed the threshold reference signal; A reset circuit connected with the signal output end of the controller, output ends of the comparison circuit and a reset end of the controller respectively, the reset circuit is triggered to output a reset signal to reset the controller when the second level signal output by the comparison circuit is received.

2. The heating protection circuit of claim 1, wherein, The sampling output circuit comprises: A current sampling circuit connected with the heating circuit, the current sampling circuit is used for sampling working current or output current of the heating circuit and outputting current sampling signals; A temperature sampling circuit arranged relative to the heating body, the temperature sampling circuit is used for sampling temperature of the heating body and outputting temperature sampling signals.

3. The heating protection circuit of claim 2, wherein, The comparison circuit comprises a first comparator and a second comparator; An inverting input end of the first comparator is connected with an output end of the current sampling circuit, a non-inverting input end of the first comparator is used for inputting a first threshold reference voltage, an inverting input end of the second comparator is connected with an output end of the temperature sampling circuit, a non-inverting input end of the second comparator is used for inputting a second threshold reference voltage, an output end of the first comparator and an output end of the second comparator are connected to constitute an output end of the comparison circuit.

4. The heating protection circuit of claim 3, wherein, The first comparator and the second comparator are integrated into a comparison chip.

5. The heating protection circuit of claim 1, wherein, The first level signal is a high level signal and the second level signal is a low level signal; The reset circuit comprises: A pull-up circuit connected with the reset end of the controller, the pull-up circuit is used for pulling up the reset end of the controller to a high level when no signal is inputted; A signal switching circuit connected with the signal output end of the controller, the output end of the comparison circuit and the pull-up circuit, the signal switching circuit is triggered to output low level to the pull-up circuit and the reset end of the controller when the second level signal output by the comparison circuit is received.

6. The heating protection circuit of claim 5, wherein, The pull-up circuit comprises a first resistor and a first capacitor; The first end of the first resistor is connected with a positive power supply end, the second end of the first resistor, the first end of the first capacitor and the reset end of the controller are connected, and the second end of the first capacitor is grounded.

7. The heating protection circuit of claim 5, wherein, The signal switching circuit comprises a second resistor, a second capacitor, a first electronic switch tube and a second electronic switch tube. The first end of the second resistor is connected with the signal output end of the controller, the second end of the second resistor, the control end of the first electronic switch tube, the first end of the second capacitor and the first end of the second electronic switch tube are connected, the control end of the second electronic switch tube is connected with the signal output end of the controller and the output end of the comparison circuit respectively, the second end of the second electronic switch tube is grounded, the second end of the second capacitor is grounded, the second end of the first electronic switch tube is grounded, and the first end of the first electronic switch tube constitutes the output end of the signal switching circuit.

8. The heating protection circuit of claim 5, wherein, The reset circuit further comprises: A voltage dividing circuit, the input end of the voltage dividing circuit is connected with the signal output end of the controller, the voltage dividing output end of the voltage dividing circuit is connected with the enable end of the heating circuit and the output end of the comparison circuit respectively, and the voltage dividing circuit is used for voltage dividing output of a level signal output by the controller.

9. The heating protection circuit of claim 8, wherein, The voltage dividing circuit comprises a third resistor and a fourth resistor. The first end of the third resistor is connected with the signal output end of the controller, the second end of the third resistor, the first end of the fourth resistor, the enable end of the heating circuit, the output end of the comparison circuit and the control end of the signal switching circuit are connected, and the second end of the fourth resistor is grounded.

10. An aerosol-generating device comprising: The heating protection circuit comprises a controller, a heating circuit, a heating body and the heating protection circuit as claimed in any one of claims 1 to 9, and the heating protection circuit is connected with the heating circuit and the controller respectively. The signal output end of the controller is connected with the enable end of the heating circuit, the controller is used for outputting a first level signal to control the heating circuit to heat the heating body and outputting a second level signal to control the heating circuit to stop heating the heating body, and the first level signal and the second level signal are opposite level signals.

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