CN118201148A - Heating circuit, heating method and heating device - Google Patents

Abstract

The invention discloses a heating circuit, which comprises: one end of the first controllable switch is connected with a power supply of the heating circuit: one end of the oscillating circuit is connected with the other end of the first controllable switch, and the other end of the oscillating circuit is grounded; the oscillating circuit comprises a first branch and a second branch which are connected in parallel, the first branch comprises a first capacitor, the second branch comprises an inductance coil and a second capacitor which are connected in series, and the inductance coil can generate induction current in the heating element when being electrified. The heating circuit provided by the invention avoids the problem of high-temperature heating caused by short circuit of the power supply to the ground when the controllable switch is fully conducted. The invention also provides a heating method and a heating device.

Description

Heating circuit, heating method and heating device

Technical Field

The invention relates to the field of novel tobaccos, in particular to a heating circuit, a heating method and a heating device.

Background

The traditional tobacco is harmful to the health of users, and the novel aerosol generating device is taken as a substitute commodity of the traditional tobacco, so that the development in recent years is rapid. Common aerosol-generating devices can be broadly classified into electronic cigarettes, heated cigarettes, and the like, according to the form of aerosol-generating material. The aerosol-generating materials used in electronic cigarettes are liquid materials, while the aerosol-generating materials used in heating cigarettes are solid materials, i.e. solid aerosol-forming substrates, such as tobacco flakes, tobacco particles, cut filler, reconstituted tobacco, etc.

The heating modes of the existing aerosol generating device mainly comprise resistance heating and electromagnetic heating. The principle of the aerosol generating device for resistance heating is that electric energy is converted into heat energy by utilizing the Joule effect of electric current, the heat energy is generated by a heating element and is transmitted to a heated object by radiation, convection, conduction and the like. The principle of the electromagnetic heating aerosol generating device is that an alternating voltage with high frequency is applied to an electromagnetic heating coil wound on the surface of a heated object to generate a magnetic field, and the magnetic field is applied to the surface of the object to be heated to generate eddy currents inside the object to be heated to generate heat.

The electromagnetic driving modes include single-tube driving, half-bridge driving, full-bridge driving, E-type power amplifier driving and the like. The half bridge type driving adopts the upper bridge arm and the lower bridge arm to be respectively controlled, and the upper bridge arm and the lower bridge arm are conducted in a time-sharing way to control the flowing direction of current in the coil so as to realize the alternating of an electric field in the coil and form a stable changing magnetic field, so that a susceptor in the magnetic field heats and heats the cigarette media. In the existing half-bridge driving circuit, the upper bridge arm and the lower bridge arm are respectively connected with a power supply and the ground, and when a system goes wrong, the upper bridge arm and the lower bridge arm can be simultaneously in an open state, so that the power supply is short-circuited to the ground, and the risk of high-temperature heating is further caused.

Disclosure of Invention

The invention aims to solve the problem that in the existing half-bridge type driving circuit, when an upper bridge arm and a lower bridge arm are simultaneously conducted, a power supply is short-circuited to the ground, so that the risk of high-temperature heating is caused.

In the first aspect, the heating circuit provided by the invention avoids the problem of high-temperature heating caused by short circuit of the power supply to the ground when the controllable switch is all conducted.

To solve the above technical problems, an embodiment of the present invention discloses a heating circuit, including: one end of the first controllable switch is connected with a power supply of the heating circuit: one end of the oscillating circuit is connected with the other end of the first controllable switch, and the other end of the oscillating circuit is grounded; the oscillating circuit comprises a first branch and a second branch which are connected in parallel, the first branch comprises a first capacitor, the second branch comprises an inductance coil and a second capacitor which are connected in series, and the inductance coil can generate induction current in the heating element when being electrified.

By adopting the technical scheme, the heating circuit provided by the invention is provided with the first capacitor and the second capacitor on the loop between the power supply and the ground, the first capacitor and the second capacitor are connected in parallel, and the capacitor is isolated from direct-current and alternating-current characteristics, so that even if the controllable switch is simultaneously conducted, the heating circuit is not short-circuited, and the high-temperature problem caused by the short-circuit is avoided.

According to another embodiment of the invention, the first branch further comprises a second controllable switch in series with the first capacitor.

According to another embodiment of the invention, the second branch further comprises a second controllable switch in series with the inductor and the second capacitor.

In a second aspect, embodiments of the present invention disclose a heating method, comprising a heating circuit as described above, the method comprising: controlling the first controllable switch to be conducted so that the power supply charges the first capacitor or the second capacitor; based on determining that the first capacitance or the second capacitance satisfies a first condition, the first controllable switch is controlled to be turned off so that an oscillating current is generated in the oscillating circuit.

By adopting the technical scheme, the first capacitor and the second capacitor which are connected in parallel are arranged between the power supply and the grounding end, so that the heating function of the heating circuit on the target object is realized, the power supply is prevented from being short-circuited to the ground, and the high-temperature heating risk caused by the power supply and the grounding end is prevented.

According to another embodiment of the present invention, the first condition includes: the voltage, current or power of the first capacitor or the second capacitor is larger than a preset threshold value.

According to another embodiment of the invention, the heating circuit is a heating circuit according to any one of claims 2 to 3; the step of controlling the first controllable switch to be turned on comprises the step of controlling the second controllable switch to be turned off;

After said controlling the first controllable switch to open, the method further comprises:

And controlling the second controllable switch to be conducted.

According to another embodiment of the present invention, when the heating temperature of the heating element exceeds a preset temperature, the second controllable switch is controlled to be turned off or the first controllable switch and the second controllable switch are controlled to be turned on.

According to another embodiment of the present invention, when the real-time electric quantity of the first capacitor or the second capacitor is lower than a preset threshold value, the first controllable switch is turned on, so that the power supply charges the first capacitor or the second capacitor.

In a third aspect, the present invention provides a heating device comprising: a heating circuit as described above; and a heating element, wherein the inductor in the heating circuit is configured to generate an induced current in the heating element.

By adopting the technical scheme, the heating device can heat the heating element by utilizing the electromagnetic heating principle through the heating circuit, and the heating circuit can avoid short circuit so as to reduce damage to the heating device caused by overheating, and simultaneously satisfy the sensory experience of a user and prevent accidents caused by damage of the user.

In a fourth aspect, the present invention provides a heating device adopting the foregoing heating method, including a heating element, wherein an inductance coil in the heating circuit is used to generate an induced current in the heating element.

By adopting the technical scheme, the heating device can adopt the heating method to heat the heating element by utilizing the electromagnetic heating principle through the heating circuit, and the heating circuit can avoid short circuit so as to reduce the damage of overheat to the heating device, simultaneously satisfy the sensory experience of a user and prevent the occurrence of accidents caused by the damage of the user.

Drawings

Fig. 1 shows a circuit diagram of a heating circuit in a first embodiment of the invention;

FIG. 2 shows a circuit diagram of a heating circuit in a second embodiment of the invention;

FIG. 3 shows a second circuit diagram of a heating circuit in a second embodiment of the invention;

Fig. 4 shows a third circuit diagram of a heating circuit in a second embodiment of the invention;

FIG. 5 shows a first current waveform in an embodiment of the invention;

FIG. 6 shows a second current waveform diagram in one embodiment of the invention;

Fig. 7 shows a circuit diagram of a heating circuit in a third embodiment of the invention;

FIG. 8 shows a flow chart of a heating method in one embodiment of the invention;

FIG. 9 shows a second flowchart of a heating method in one embodiment of the invention.

Detailed Description

Further advantages and effects of the present invention will become apparent to those skilled in the art from the disclosure of the present specification, by describing the embodiments of the present invention with specific examples. While the description of the invention will be described in connection with the preferred embodiments, it is not intended to limit the inventive features to the implementation. Rather, the purpose of the invention described in connection with the embodiments is to cover other alternatives or modifications, which may be extended by the claims based on the invention. The following description will include numerous specific details in order to provide a thorough understanding of the present invention. The invention may be practiced without these specific details. Furthermore, some specific details are omitted from the description in order to avoid obscuring the invention. It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.

It should be noted that in this specification, like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

The terms "first," "second," and the like are used merely to distinguish between descriptions and are not to be construed as indicating or implying relative importance.

In the description of the present embodiment, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present embodiment can be understood in a specific case by those of ordinary skill in the art.

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Referring to fig. 1, in a first embodiment of the present invention, a heating circuit 1, a classical electromagnetic half-bridge driving circuit, is provided. The heating circuit 1 comprises two parallel branches, an upper bridge branch and a lower bridge branch.

The upper bridge branch circuit comprises an upper arm electronic switch IGBT1 (insulated gate bipolar transistor, english is Insulated Gate Bipolar Transistor, IGBT for short), a first capacitor C1 and an inductance coil L which are connected in series. The lower bridge branch circuit comprises a lower arm electronic switch IGBT2, a second capacitor C2 and an inductance coil L which are connected in series. In the heating circuit 1, a power supply of the heating circuit 1 is respectively connected with an upper arm electronic switch IGBT1 and a first capacitor C1 of an upper bridge branch; the ground terminal of the heating circuit 1 is respectively connected with the lower arm electronic switch IGBT2 and the second capacitor C2.

The first capacitor C1 and the second capacitor C2 are nonpolar capacitors; l is an inductance coil; the upper arm electronic switch and the lower arm electronic switch can be IGBT, MOS or Darlington tube; VCC is the power supply of the heating circuit 1, and the power supply provides power supply voltage for the heating circuit 1; GND is the ground, or reference plane, of the heating circuit, i.e., ground.

Referring to fig. 1, the heating circuit 1 operates on the principle that:

When the upper arm electronic switch IGBT1 is turned on, the lower arm electronic switch IGBT2 is turned off, and the current flows from the power source VCC through the upper arm electronic switch IGBT1, the inductor L, and the second capacitor C2 and then is grounded, that is, the current flowing through the inductor L is from left to right, and the current in the inductor L gradually increases until reaching a peak value due to the characteristic of maintaining the current in the inductor L. The upper arm electronic switch IGBT1 is kept in a conducting state, and the voltage at two ends of the second capacitor C2 is gradually increased in the charging process, so that the voltage difference at two ends of the inductance coil L is gradually reduced, and the inductance coil L continuously outputs current and gradually reduces from a peak value due to the characteristic of the holding current of the inductance coil L. Then, the upper arm electronic switch IGBT1 is turned off.

When the lower arm electronic switch IGBT2 is turned on, the upper arm electronic switch IGBT1 is turned off, and the current flows from the power supply VCC through the first capacitor C1, the inductance coil L, and the lower arm electronic switch IGBT2, and then is grounded. The current direction of the inductor L is from right to left, and the current in the inductor L increases gradually until the peak value is reached due to the characteristic of the holding current of the inductor L. The lower arm electronic switch IGBT2 is kept in a conducting state, the inductance coil L continuously outputs current due to the characteristic of keeping current of the inductance coil L, the second capacitor C2 discharges to the ground GND through the inductance coil L and the lower arm switch IGBT2, and along with the reduction of energy storage of the second capacitor C2, the current flowing through the inductance coil L gradually decreases from a peak value until energy in the inductance coil L is radiated. The heating circuit 1 is controlled to be in different working states by the on and off of the upper arm electronic switch IGBT1 and the lower arm electronic switch IGBT2, so that the electric field alternation of the inductance coil L is realized, and a changing magnetic field is generated to heat a heating element positioned in the magnetic field.

In the present embodiment, in the heating circuit 1, if the upper arm electronic switch IGBT1 and the lower arm electronic switch IGBT2 are turned on at the same time, the power supply VCC is short-circuited to the ground terminal GND. That is, the resistances of the upper arm electronic switch IGBT1 and the lower arm electronic switch IGBT2 are smaller, and the current is too large, so that a large amount of heat is formed on the upper arm electronic switch IGBT1 and the lower arm electronic switch IGBT2, which results in high temperature of the upper arm electronic switch IGBT1 and the lower arm electronic switch IGBT2, causing serious system risk and having potential safety hazard.

For this purpose, with reference to fig. 2 to 4, in a second embodiment of the invention, a heating circuit 2 is provided. The heating circuit 2 comprises a controllable switch. In some possible embodiments provided by the invention, the controllable switch is any one of a single pole switch, an IGBT, a MOS transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, abbreviated as MOSFET, abbreviated as MOS transistor), and a darlington transistor. Fig. 2 shows a heating circuit 21 with controllable switches being IGBTs. Fig. 3 shows a heating circuit 22 with a controllable switch being a single pole switch. Fig. 4 shows a heating circuit 23 with controllable switches as MOS transistors.

Referring to fig. 2, the heating circuit 21 includes a first controllable switch IGBT1 and an oscillating circuit. One end of the first controllable switch IGBT1 is connected to a power supply VCC of the heating circuit 21. One end of the oscillating circuit is connected with the other end of the first controllable switch IGBT1, and the other end of the oscillating circuit is grounded to GND. The oscillating circuit comprises a first branch and a second branch which are connected in parallel, the first branch comprises a first capacitor C1, the second branch comprises an inductance coil L and a second capacitor C2 which are connected in series, and the inductance coil L can generate induction current in the heating element when being electrified.

By adopting the technical scheme, the first capacitor C1 and the second capacitor C2 are arranged between the power supply VCC and the ground end GND, the first capacitor C1 and the second capacitor C2 are arranged in parallel, the heating function of the heating circuit 21 on a target object is realized, the short circuit of the power supply VCC to the ground GND is prevented, and the high-temperature heating risk caused by the short circuit is prevented.

In the heating circuit 21, the first capacitor C1 and the second capacitor C2 are nonpolar capacitors; l is an inductance coil; the upper arm electronic switch and the lower arm electronic switch can be IGBT, MOS or Darlington tube; VCC is the power supply of the heating circuit 1, and the power supply provides power supply voltage for the heating circuit 1; GND is the ground terminal, CTL is the signal input terminal, and this signal input terminal is connected with little control unit MCU each other for receive little control unit MCU's control signal in order to switch on or break off first controllable switch or second controllable switch.

In the heating circuit 21, the first controllable switch IGBT1 is controlled to be turned on so that the power supply VCC charges the first capacitor C1; the first controllable switch IGBT1 is controlled to be turned off so that the first branch and the second branch form an oscillating circuit, and the inductance coil L is supplied with current to heat the target object provided with the heating element.

In some other possible embodiments provided by the present invention, the second branch further includes a second controllable switch IGBT2 connected in series with the inductor L1 and the second capacitor C2. I.e. the second branch further comprises a second controllable switch IGBT2, the second capacitance C2 being connected to ground via the second controllable switch IGBT2.

Referring to fig. 2, the heating circuit 21 operates on the principle that:

The first controllable switch IGBT1 is turned on, the second controllable switch IGBT2 is turned off, the voltage at the point A is equal to the voltage of the power supply VCC, and current flows from the power supply VCC to the ground end GND through the first controllable switch IGBT1 and the first capacitor C1. In this process, the power supply VCC charges the first capacitor C1 such that the voltage of the a terminal of the first capacitor C1 to the ground GND is equal to the voltage of the power supply VCC. (assuming here that the first controllable switch IGBT1 and the second controllable switch IGBT2 are both ideal switches, no internal resistance).

The first controllable switch IGBT1 is turned off, the second controllable switch IGBT2 is turned on, and the voltage at the point C is equal to the voltage of the ground end GND. The first capacitor C1, the inductance coil L1, the second capacitor C2 and the second controllable switch IGBT2 form a loop, and because the first capacitor C1 stores electricity and the second capacitor C2 does not store electricity, the voltage at the point A is higher than that at the point B, the first capacitor C1 charges the second capacitor C2 through the inductance coil L1, and at the moment, the current direction is the first capacitor C1, the inductance coil L1, the second capacitor C2, the second controllable switch IGBT2 and the grounding end GND. Since the inductance coil L1 is an inductive element, and has a characteristic of blocking a current change, the current gradually increases. When the voltages at two points A, B are equal, the current in inductor L1 reaches a maximum. Because of the characteristic of the holding current of the inductor, the first capacitor C1 will continue to charge the second capacitor C2, the charging current will gradually decrease, the voltage at the point B will gradually increase, and when the current on the inductor L1 is zero, the second capacitor C2 will charge and stop.

Since the current of the inductor L1 is zero and the voltage of the second capacitor C2 is higher than the voltage of the first capacitor C1, the second capacitor C2 charges the first capacitor C1 through the inductor L1, and the current flowing through the inductor L1 is opposite to the current flowing through the inductor L1 when the first capacitor C1 charges the second capacitor C2.

When the first controllable switch IGBT1 is disconnected and the second controllable switch IGBT2 is conducted, the first capacitor C1 is continuously and circularly charged for the second capacitor C2, the second capacitor C2 is charged for the first capacitor C1, alternating current is formed on the inductance coil L1 through the process, alternating current in the inductance coil L1 forms an alternating magnetic field, and eddy currents are generated on the surface of a heating element positioned in the magnetic field, so that the heating element generates heat and is used for heating a target object.

In some possible embodiments of the present invention, as described above, the first controllable switch is any one of a single-pole switch, an IGBT, a MOS transistor, and a darlington transistor, and the second controllable switch is any one of a single-pole switch, an IGBT, a MOS transistor, and a darlington transistor.

In the heating circuit 21, even if the first controllable switch IGBT1 and the second controllable switch IGBT2 are turned on at the same time, since the first capacitor C1 and the second capacitor C2 connected in parallel are provided between the power supply VCC and the ground GND, it is possible to prevent the power supply VCC from shorting to the ground GND and to prevent the risk of high-temperature heat generation caused thereby.

Referring to fig. 3, the present invention provides a heating circuit 22, and the heating circuit 22 is different from the heating circuit 21 only in that the first controllable switch and the second controllable switch are both single-pole switches. The heating principle of the heating circuit 22 is the same as that of the heating circuit 21, and will not be described here.

Referring to fig. 4, the present invention provides a heating circuit 23, and the heating circuit 23 is different from the heating circuit 22 and the heating circuit 21 only in that the first controllable switch and the second controllable switch are both MOS transistors. In the heating circuit 23, a source S of the first controllable switch Q1 is connected to a power source, a gate G is connected to a signal input terminal, and a drain D is connected to one end of an oscillating circuit. The source electrode S of the second controllable switch Q2 is grounded, the grid electrode G is connected with the signal input end, and the drain electrode D is connected with the second capacitor C2. The heating principle of the heating circuit 23 is the same as that of the heating circuits 21 and 22, and will not be described here.

Referring to fig. 5, there is shown a current waveform at point B (as shown in fig. 2) when the heating circuit 2 is continuously operated, the current waveform having an approximately sinusoidal waveform.

Referring to fig. 6, a single current oscillation waveform at point B (as shown in fig. 2) is shown when the heating circuit 2 is continuously operated. That is, the waveform of the current formed when the heating circuit 2 is charged once is in a damped oscillation shape, and is characterized in that the oscillation waveform becomes smaller and smaller until it disappears with time.

Referring to fig. 7, in a third embodiment of the present invention, the heating circuit 3 includes a first controllable switch Q1 and an oscillating circuit.

One end of the first controllable switch Q1 is connected to the power supply VCC of the heating circuit 3. One end of the oscillating circuit is connected with the other end of the first controllable switch Q1, and the other end of the oscillating circuit is grounded to GND. The oscillating circuit comprises a first branch and a second branch which are connected in parallel, wherein the first branch comprises a first capacitor C1 and a second controllable switch Q2 which are connected in series, and the first capacitor C1 is grounded GND through the second controllable switch Q2. The second branch comprises an inductance coil L1 and a second capacitor C2 which are connected in series, and the inductance coil L1 can generate induction current in the heating element when being electrified.

When the first controllable switch Q1 is turned on, the power source VCC charges the second capacitor C2 due to the characteristic of the inductor L1 having a straight-line-to-isolated communication.

When the first controllable switch Q1 is turned off and the second controllable switch Q2 is turned on, the oscillating circuit (i.e., the first branch and the second branch) continuously and circularly repeats the charging of the first capacitor C1 by the second capacitor C2 and the charging of the second capacitor C2 by the first capacitor C1, through the above process, an alternating current is formed on the inductor coil L1, and an alternating current in the inductor coil L1 forms an alternating magnetic field, so that an eddy current is generated on the surface of the heating element located in the magnetic field, and the heating element generates heat for heating the target object. Namely, the heating principle of the heating circuit 3 is the same as that of the heating circuit 2, and will not be described here.

When the first controllable switch Q1 and the second controllable switch Q2 are simultaneously conducted, a first capacitor C1 and the second controllable switch Q2 are connected in series between the power supply VCC and the ground end GND, the power supply VCC charges the first capacitor C1, short circuit of the power supply VCC to the ground GND is prevented, and the high-temperature heating risk caused by the short circuit is prevented.

In a second aspect, referring to fig. 8, the present invention provides a heating method for a heating circuit. The heating circuit is the heating circuit in any of the foregoing embodiments. The heating method comprises the following steps:

S1: controlling the first controllable switch IGBT1 to be conducted so that the power supply VCC charges the first capacitor C1;

S2: based on determining that the first capacitance C1 satisfies the first condition, the first controllable switch IGBT1 is controlled to be turned off so that an oscillating current is generated in the oscillating circuit. The inductance coil L1 is supplied with current to heat the heating element.

By adopting the technical scheme, the first capacitor C1 and the second capacitor C2 which are connected in parallel are arranged between the power supply VCC and the ground end GND, so that the heating function of the heating circuit 2 on the heating element is realized, the short circuit of the power supply VCC to the ground GND is prevented, and the high-temperature heating risk caused by the short circuit is prevented.

Illustratively, in some possible embodiments provided by the present invention, the first condition includes: the voltage of the first capacitor C1 is greater than a preset threshold. I.e. until the first capacitor C1 is fully charged, the first controllable switch IGBT1 is controlled to be turned off. As another example, in some possible embodiments provided by the present invention, the first condition includes: the current of the first capacitor C1 is greater than a preset threshold value, and the first controllable switch IGBT1 is controlled to be turned off. For another example, the first condition includes: the power of the first capacitor C1 is larger than a preset threshold value, and the first controllable switch IGBT1 is controlled to be turned off.

In some other possible embodiments provided by the present invention, referring to fig. 2 to 5, the heating circuit is the heating circuit 2 described in the second embodiment and the heating circuit 3 described in the third embodiment, referring to fig. 2, at S2: based on determining that the first capacitance C1 satisfies the first condition, after controlling the first controllable switch IGBT1 to be turned off, the heating method further includes: the second controllable switch IGBT2 is controlled to conduct.

Specifically, referring to fig. 9 in combination with fig. 2, the heating method of the heating circuit 21 is:

S11: the first controllable switch IGBT1 is controlled to be conducted, and the second controllable switch IGBT2 is controlled to be disconnected, so that the power supply VCC charges the first capacitor C1;

S12: based on determining that the first capacitor C1 meets the first condition, the first controllable switch IGBT1 is controlled to be turned off and the second controllable switch IGBT2 is controlled to be turned on, so that an oscillating current is generated in the oscillating circuit, and the inductance coil L1 is capable of generating an induced current in the heating element.

Illustratively, as previously described, the first condition comprises: the voltage of the first capacitor C1 is greater than a preset threshold, or the current of the first capacitor C1 is greater than a preset threshold, or the power of the first capacitor C1 is greater than a preset threshold. The invention is not limited in this regard.

In a third aspect, the present invention provides a heating device (not shown in the figures) comprising a heating circuit 2 or heating circuit 3 and a heating element as described above. Wherein the inductor L1 in the heating circuit 2 or the heating circuit 3 is used for generating an induction current in the heating element. By adopting the technical scheme, the heating device can heat the heating element by utilizing the electromagnetic heating principle through the heating circuit 2 or the heating circuit 3, and the heating circuit 2 or the heating circuit 3 can avoid short circuit so as to reduce the damage of overheat to the heating device, simultaneously satisfy the sensory experience of a user and prevent the occurrence of accidents of the damage of the user.

In the present invention, the operation of the heating device will be described by taking the heating circuit 21 of the second embodiment shown in fig. 2 as an example:

the heating means comprise a heating circuit 21 and a micro control unit MCU. The micro control unit MCU is connected with the signal receiving ends of CTL1 and CTL2 of the heating circuit 21.

The heating device is started, a program is set to enable the micro control unit MCU to send a signal for controlling the first controllable switch IGBT1 to be conducted, the CTL1 receives the signal and conducts the first controllable switch IGBT1, in the heating circuit 21, the power supply VCC charges the first capacitor C1 until the first capacitor C1 is fully charged, and the micro control unit MCU controls the first controllable switch IGBT1 to be disconnected through the CTL 1.

Then, the micro control unit MCU sends out a signal for controlling the second controllable switch IGBT2 to be turned on, and since the level in the first capacitor C1 is inconsistent with the level of the second capacitor C2, that is, the level in the first capacitor C1 is higher than the level of the second capacitor C2, the first capacitor C1 charges the second capacitor C2 through the inductor L1, and a varying current flows through the inductor L1. Since the inductor L1 is an inductive load, it has a characteristic of maintaining the current unchanged, an overshoot is generated during the process of charging the first capacitor C1 to the second capacitor C2, i.e. the level of the second capacitor C2 is higher than that of the first capacitor C1. At this time, the second capacitor C2 charges the first capacitor C1 through the inductor L1 again, so that alternating current is generated in the inductor L1, and the heating element located in the magnetic field is heated by the electromagnetic heating principle.

The heating device further comprises a temperature measuring unit, the temperature measuring unit can measure the heating temperature of the heating element, and when the heating temperature of the heating element exceeds the preset temperature, the micro control unit MCU controls the second controllable switch IGBT2 to be turned off, and heating of the heating element is stopped, so that the heating element is cooled.

Then, when the heating temperature of the heating element is lower than the preset temperature, the micro control unit MCU controls the first controllable switch IGBT1 to maintain the off state through the CTL1, and controls the second controllable switch IGBT2 to turn on through the CTL2, that is, the oscillating circuit operates to make the heating circuit 21 continue heating the heating element.

Or as mentioned above, the heating device further comprises a temperature measuring unit, the temperature measuring unit can measure the heating temperature of the heating element, and when the heating temperature of the heating element exceeds the preset temperature, the micro control unit MCU controls the first controllable switch IGBT1 to be turned on and the second controllable switch IGBT2 to be turned on so as to cool the heating element. In this process, since the first capacitor C1 and the second capacitor C2 connected in parallel are disposed on the loop between the power VCC and the ground GND, the capacitors have the characteristic of isolating the direct current from the direct current, so that the high temperature risk caused by the short circuit will not occur even if the first controllable switch IGBT1 and the second controllable switch IGBT2 are all turned on at the same time.

Then, when the heating temperature of the heating element is lower than the preset temperature, the micro control unit MCU controls the first controllable switch IGBT1 to be turned off through the CTL1, and controls the second controllable switch IGBT2 to be turned on through the CTL2, that is, the oscillating circuit works to enable the heating circuit 21 to continue heating the heating element.

In the above process, the heating device further includes an electric quantity monitoring unit for monitoring the real-time electric quantity of the first capacitor C1 and the second capacitor C2, when the real-time electric quantity of the first capacitor C1 is lower than a preset threshold value, the micro control unit MCU controls the first controllable switch IGBT1 to be turned on, so that the power VCC charges the first capacitor C1 until the first capacitor C1 is fully charged, and the micro control unit MCU controls the first controllable switch IGBT1 to be turned off.

When the heating device is used, the micro control unit MCU controls the first controllable switch IGBT1 to be turned off through the CTL1, controls the second controllable switch IGBT2 to be turned off through the CTL2, and closes the heating circuit 21.

In a fourth aspect, the present invention provides a heating apparatus (not shown in the drawings) employing the foregoing heating method, comprising the heating element as described above, wherein the inductor L1 in the heating circuit is configured to generate an induction current in the heating element for heating the target object.

By adopting the technical scheme, the heating device adopting the heating method can heat the heating element by utilizing the electromagnetic heating principle through the heating circuit 2, and the heating circuit 2 can avoid short circuit so as to reduce the damage of overheat to the heating device, simultaneously satisfy the sensory experience of a user and prevent the occurrence of accidents of the damage of the user.

In some possible embodiments provided by the invention, the heating device is an aerosol-generating device. Illustratively, for example, the aerosol-generating device is an electronic cigarette, the electronic cigarette liquid being heated by the heating circuit 2 to meet the user's smoking experience; as another example, the aerosol-generating device is a heated non-burning smoking article that is heated by the heating circuit 2 to meet the user's smoking experience.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing is a further detailed description of the invention with reference to specific embodiments, and it is not intended to limit the practice of the invention to those descriptions. Various changes in form and detail may be made therein by those skilled in the art, including a few simple inferences or alternatives, without departing from the spirit and scope of the present invention.

Claims (10)

1.A heating circuit, comprising:

one end of the first controllable switch is connected with a power supply of the heating circuit:

the oscillating circuit is connected with one end of the first controllable switch and the other end of the oscillating circuit is grounded;

The oscillating circuit comprises a first branch and a second branch which are connected in parallel, wherein the first branch comprises a first capacitor, the second branch comprises an inductance coil and a second capacitor which are connected in series, and the inductance coil can generate induction current in the heating element when being electrified.

2. The heating circuit of claim 1 wherein said first branch further comprises a second controllable switch in series with said first capacitor.

3. The heating circuit of claim 1 wherein said second branch further comprises a second controllable switch in series with said inductor and said second capacitor.

4. A heating method for a heating circuit, characterized in that the heating circuit is a heating circuit as claimed in any one of claims 1 to 3, the method comprising:

controlling the first controllable switch to be conducted so that the power supply charges the first capacitor or the second capacitor;

Based on determining that the first capacitance or the second capacitance meets a first condition, the first controllable switch is controlled to be opened so that an oscillating current is generated in the oscillating circuit.

5. The heating method of claim 4, wherein the first condition comprises: the voltage, current or power of the first capacitor or the second capacitor is larger than a preset threshold value.

6. A heating method according to claim 4 or 5, wherein the heating circuit is a heating circuit according to any one of claims 2 to 3; the step of controlling the first controllable switch to be on comprises the step of controlling the second controllable switch to be off;

After said controlling the first controllable switch to open, the method further comprises:

And controlling the second controllable switch to be conducted.

7. The heating method of claim 6, wherein the second controllable switch is controlled to be turned off or the first controllable switch and the second controllable switch are controlled to be both turned on when the heating temperature of the heating element exceeds a preset temperature.

8. The heating method of claim 6, wherein the first controllable switch is turned on to charge the power supply to the first capacitor or the second capacitor when the real-time power of the first capacitor or the second capacitor is lower than a predetermined threshold.

9. A heating device, comprising:

a heating circuit as claimed in any one of claims 1 to 3; and

A heating element, wherein the inductance coil in the heating circuit is used for generating induction current in the heating element.

10. A heating device employing the heating method according to any one of claims 5 to 8, comprising the heating element, wherein the inductor coil in the heating circuit is configured to generate an induced current in the heating element.